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      1 // Copyright 2012 the V8 project authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 #if V8_TARGET_ARCH_X87
      6 
      7 #include "src/crankshaft/x87/lithium-codegen-x87.h"
      8 
      9 #include "src/base/bits.h"
     10 #include "src/code-factory.h"
     11 #include "src/code-stubs.h"
     12 #include "src/codegen.h"
     13 #include "src/crankshaft/hydrogen-osr.h"
     14 #include "src/deoptimizer.h"
     15 #include "src/ic/ic.h"
     16 #include "src/ic/stub-cache.h"
     17 #include "src/x87/frames-x87.h"
     18 
     19 namespace v8 {
     20 namespace internal {
     21 
     22 // When invoking builtins, we need to record the safepoint in the middle of
     23 // the invoke instruction sequence generated by the macro assembler.
     24 class SafepointGenerator final : public CallWrapper {
     25  public:
     26   SafepointGenerator(LCodeGen* codegen,
     27                      LPointerMap* pointers,
     28                      Safepoint::DeoptMode mode)
     29       : codegen_(codegen),
     30         pointers_(pointers),
     31         deopt_mode_(mode) {}
     32   virtual ~SafepointGenerator() {}
     33 
     34   void BeforeCall(int call_size) const override {}
     35 
     36   void AfterCall() const override {
     37     codegen_->RecordSafepoint(pointers_, deopt_mode_);
     38   }
     39 
     40  private:
     41   LCodeGen* codegen_;
     42   LPointerMap* pointers_;
     43   Safepoint::DeoptMode deopt_mode_;
     44 };
     45 
     46 
     47 #define __ masm()->
     48 
     49 bool LCodeGen::GenerateCode() {
     50   LPhase phase("Z_Code generation", chunk());
     51   DCHECK(is_unused());
     52   status_ = GENERATING;
     53 
     54   // Open a frame scope to indicate that there is a frame on the stack.  The
     55   // MANUAL indicates that the scope shouldn't actually generate code to set up
     56   // the frame (that is done in GeneratePrologue).
     57   FrameScope frame_scope(masm_, StackFrame::MANUAL);
     58 
     59   return GeneratePrologue() &&
     60       GenerateBody() &&
     61       GenerateDeferredCode() &&
     62       GenerateJumpTable() &&
     63       GenerateSafepointTable();
     64 }
     65 
     66 
     67 void LCodeGen::FinishCode(Handle<Code> code) {
     68   DCHECK(is_done());
     69   code->set_stack_slots(GetTotalFrameSlotCount());
     70   code->set_safepoint_table_offset(safepoints_.GetCodeOffset());
     71   PopulateDeoptimizationData(code);
     72   if (info()->ShouldEnsureSpaceForLazyDeopt()) {
     73     Deoptimizer::EnsureRelocSpaceForLazyDeoptimization(code);
     74   }
     75 }
     76 
     77 
     78 #ifdef _MSC_VER
     79 void LCodeGen::MakeSureStackPagesMapped(int offset) {
     80   const int kPageSize = 4 * KB;
     81   for (offset -= kPageSize; offset > 0; offset -= kPageSize) {
     82     __ mov(Operand(esp, offset), eax);
     83   }
     84 }
     85 #endif
     86 
     87 
     88 bool LCodeGen::GeneratePrologue() {
     89   DCHECK(is_generating());
     90 
     91   if (info()->IsOptimizing()) {
     92     ProfileEntryHookStub::MaybeCallEntryHook(masm_);
     93   }
     94 
     95   info()->set_prologue_offset(masm_->pc_offset());
     96   if (NeedsEagerFrame()) {
     97     DCHECK(!frame_is_built_);
     98     frame_is_built_ = true;
     99     if (info()->IsStub()) {
    100       __ StubPrologue(StackFrame::STUB);
    101     } else {
    102       __ Prologue(info()->GeneratePreagedPrologue());
    103     }
    104   }
    105 
    106   // Reserve space for the stack slots needed by the code.
    107   int slots = GetStackSlotCount();
    108   DCHECK(slots != 0 || !info()->IsOptimizing());
    109   if (slots > 0) {
    110     __ sub(Operand(esp), Immediate(slots * kPointerSize));
    111 #ifdef _MSC_VER
    112     MakeSureStackPagesMapped(slots * kPointerSize);
    113 #endif
    114     if (FLAG_debug_code) {
    115       __ push(eax);
    116       __ mov(Operand(eax), Immediate(slots));
    117       Label loop;
    118       __ bind(&loop);
    119       __ mov(MemOperand(esp, eax, times_4, 0), Immediate(kSlotsZapValue));
    120       __ dec(eax);
    121       __ j(not_zero, &loop);
    122       __ pop(eax);
    123     }
    124   }
    125 
    126   // Initailize FPU state.
    127   __ fninit();
    128 
    129   return !is_aborted();
    130 }
    131 
    132 
    133 void LCodeGen::DoPrologue(LPrologue* instr) {
    134   Comment(";;; Prologue begin");
    135 
    136   // Possibly allocate a local context.
    137   if (info_->scope()->NeedsContext()) {
    138     Comment(";;; Allocate local context");
    139     bool need_write_barrier = true;
    140     // Argument to NewContext is the function, which is still in edi.
    141     int slots = info_->scope()->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
    142     Safepoint::DeoptMode deopt_mode = Safepoint::kNoLazyDeopt;
    143     if (info()->scope()->is_script_scope()) {
    144       __ push(edi);
    145       __ Push(info()->scope()->scope_info());
    146       __ CallRuntime(Runtime::kNewScriptContext);
    147       deopt_mode = Safepoint::kLazyDeopt;
    148     } else {
    149       if (slots <= FastNewFunctionContextStub::kMaximumSlots) {
    150         FastNewFunctionContextStub stub(isolate());
    151         __ mov(FastNewFunctionContextDescriptor::SlotsRegister(),
    152                Immediate(slots));
    153         __ CallStub(&stub);
    154         // Result of FastNewFunctionContextStub is always in new space.
    155         need_write_barrier = false;
    156       } else {
    157         __ push(edi);
    158         __ CallRuntime(Runtime::kNewFunctionContext);
    159       }
    160     }
    161     RecordSafepoint(deopt_mode);
    162 
    163     // Context is returned in eax.  It replaces the context passed to us.
    164     // It's saved in the stack and kept live in esi.
    165     __ mov(esi, eax);
    166     __ mov(Operand(ebp, StandardFrameConstants::kContextOffset), eax);
    167 
    168     // Copy parameters into context if necessary.
    169     int num_parameters = info()->scope()->num_parameters();
    170     int first_parameter = info()->scope()->has_this_declaration() ? -1 : 0;
    171     for (int i = first_parameter; i < num_parameters; i++) {
    172       Variable* var = (i == -1) ? info()->scope()->receiver()
    173                                 : info()->scope()->parameter(i);
    174       if (var->IsContextSlot()) {
    175         int parameter_offset = StandardFrameConstants::kCallerSPOffset +
    176             (num_parameters - 1 - i) * kPointerSize;
    177         // Load parameter from stack.
    178         __ mov(eax, Operand(ebp, parameter_offset));
    179         // Store it in the context.
    180         int context_offset = Context::SlotOffset(var->index());
    181         __ mov(Operand(esi, context_offset), eax);
    182         // Update the write barrier. This clobbers eax and ebx.
    183         if (need_write_barrier) {
    184           __ RecordWriteContextSlot(esi, context_offset, eax, ebx,
    185                                     kDontSaveFPRegs);
    186         } else if (FLAG_debug_code) {
    187           Label done;
    188           __ JumpIfInNewSpace(esi, eax, &done, Label::kNear);
    189           __ Abort(kExpectedNewSpaceObject);
    190           __ bind(&done);
    191         }
    192       }
    193     }
    194     Comment(";;; End allocate local context");
    195   }
    196 
    197   Comment(";;; Prologue end");
    198 }
    199 
    200 
    201 void LCodeGen::GenerateOsrPrologue() {
    202   // Generate the OSR entry prologue at the first unknown OSR value, or if there
    203   // are none, at the OSR entrypoint instruction.
    204   if (osr_pc_offset_ >= 0) return;
    205 
    206   osr_pc_offset_ = masm()->pc_offset();
    207 
    208   // Interpreter is the first tier compiler now. It will run the code generated
    209   // by TurboFan compiler which will always put "1" on x87 FPU stack.
    210   // This behavior will affect crankshaft's x87 FPU stack depth check under
    211   // debug mode.
    212   // Need to reset the FPU stack here for this scenario.
    213   __ fninit();
    214 
    215   // Adjust the frame size, subsuming the unoptimized frame into the
    216   // optimized frame.
    217   int slots = GetStackSlotCount() - graph()->osr()->UnoptimizedFrameSlots();
    218   DCHECK(slots >= 0);
    219   __ sub(esp, Immediate(slots * kPointerSize));
    220 }
    221 
    222 
    223 void LCodeGen::GenerateBodyInstructionPre(LInstruction* instr) {
    224   if (instr->IsCall()) {
    225     EnsureSpaceForLazyDeopt(Deoptimizer::patch_size());
    226   }
    227   if (!instr->IsLazyBailout() && !instr->IsGap()) {
    228     safepoints_.BumpLastLazySafepointIndex();
    229   }
    230   FlushX87StackIfNecessary(instr);
    231 }
    232 
    233 
    234 void LCodeGen::GenerateBodyInstructionPost(LInstruction* instr) {
    235   // When return from function call, FPU should be initialized again.
    236   if (instr->IsCall() && instr->ClobbersDoubleRegisters(isolate())) {
    237     bool double_result = instr->HasDoubleRegisterResult();
    238     if (double_result) {
    239       __ lea(esp, Operand(esp, -kDoubleSize));
    240       __ fstp_d(Operand(esp, 0));
    241     }
    242     __ fninit();
    243     if (double_result) {
    244       __ fld_d(Operand(esp, 0));
    245       __ lea(esp, Operand(esp, kDoubleSize));
    246     }
    247   }
    248   if (instr->IsGoto()) {
    249     x87_stack_.LeavingBlock(current_block_, LGoto::cast(instr), this);
    250   } else if (FLAG_debug_code && FLAG_enable_slow_asserts &&
    251              !instr->IsGap() && !instr->IsReturn()) {
    252     if (instr->ClobbersDoubleRegisters(isolate())) {
    253       if (instr->HasDoubleRegisterResult()) {
    254         DCHECK_EQ(1, x87_stack_.depth());
    255       } else {
    256         DCHECK_EQ(0, x87_stack_.depth());
    257       }
    258     }
    259     __ VerifyX87StackDepth(x87_stack_.depth());
    260   }
    261 }
    262 
    263 
    264 bool LCodeGen::GenerateJumpTable() {
    265   if (!jump_table_.length()) return !is_aborted();
    266 
    267   Label needs_frame;
    268   Comment(";;; -------------------- Jump table --------------------");
    269 
    270   for (int i = 0; i < jump_table_.length(); i++) {
    271     Deoptimizer::JumpTableEntry* table_entry = &jump_table_[i];
    272     __ bind(&table_entry->label);
    273     Address entry = table_entry->address;
    274     DeoptComment(table_entry->deopt_info);
    275     if (table_entry->needs_frame) {
    276       DCHECK(!info()->saves_caller_doubles());
    277       __ push(Immediate(ExternalReference::ForDeoptEntry(entry)));
    278       __ call(&needs_frame);
    279     } else {
    280       __ call(entry, RelocInfo::RUNTIME_ENTRY);
    281     }
    282   }
    283   if (needs_frame.is_linked()) {
    284     __ bind(&needs_frame);
    285     /* stack layout
    286        3: entry address
    287        2: return address  <-- esp
    288        1: garbage
    289        0: garbage
    290     */
    291     __ push(MemOperand(esp, 0));                 // Copy return address.
    292     __ push(MemOperand(esp, 2 * kPointerSize));  // Copy entry address.
    293 
    294     /* stack layout
    295        4: entry address
    296        3: return address
    297        1: return address
    298        0: entry address  <-- esp
    299     */
    300     __ mov(MemOperand(esp, 3 * kPointerSize), ebp);  // Save ebp.
    301     // Fill ebp with the right stack frame address.
    302     __ lea(ebp, MemOperand(esp, 3 * kPointerSize));
    303 
    304     // This variant of deopt can only be used with stubs. Since we don't
    305     // have a function pointer to install in the stack frame that we're
    306     // building, install a special marker there instead.
    307     DCHECK(info()->IsStub());
    308     __ mov(MemOperand(esp, 2 * kPointerSize),
    309            Immediate(Smi::FromInt(StackFrame::STUB)));
    310 
    311     /* stack layout
    312        3: old ebp
    313        2: stub marker
    314        1: return address
    315        0: entry address  <-- esp
    316     */
    317     __ ret(0);  // Call the continuation without clobbering registers.
    318   }
    319   return !is_aborted();
    320 }
    321 
    322 
    323 bool LCodeGen::GenerateDeferredCode() {
    324   DCHECK(is_generating());
    325   if (deferred_.length() > 0) {
    326     for (int i = 0; !is_aborted() && i < deferred_.length(); i++) {
    327       LDeferredCode* code = deferred_[i];
    328       X87Stack copy(code->x87_stack());
    329       x87_stack_ = copy;
    330 
    331       HValue* value =
    332           instructions_->at(code->instruction_index())->hydrogen_value();
    333       RecordAndWritePosition(value->position());
    334 
    335       Comment(";;; <@%d,#%d> "
    336               "-------------------- Deferred %s --------------------",
    337               code->instruction_index(),
    338               code->instr()->hydrogen_value()->id(),
    339               code->instr()->Mnemonic());
    340       __ bind(code->entry());
    341       if (NeedsDeferredFrame()) {
    342         Comment(";;; Build frame");
    343         DCHECK(!frame_is_built_);
    344         DCHECK(info()->IsStub());
    345         frame_is_built_ = true;
    346         // Build the frame in such a way that esi isn't trashed.
    347         __ push(ebp);  // Caller's frame pointer.
    348         __ push(Immediate(Smi::FromInt(StackFrame::STUB)));
    349         __ lea(ebp, Operand(esp, TypedFrameConstants::kFixedFrameSizeFromFp));
    350         Comment(";;; Deferred code");
    351       }
    352       code->Generate();
    353       if (NeedsDeferredFrame()) {
    354         __ bind(code->done());
    355         Comment(";;; Destroy frame");
    356         DCHECK(frame_is_built_);
    357         frame_is_built_ = false;
    358         __ mov(esp, ebp);
    359         __ pop(ebp);
    360       }
    361       __ jmp(code->exit());
    362     }
    363   }
    364 
    365   // Deferred code is the last part of the instruction sequence. Mark
    366   // the generated code as done unless we bailed out.
    367   if (!is_aborted()) status_ = DONE;
    368   return !is_aborted();
    369 }
    370 
    371 
    372 bool LCodeGen::GenerateSafepointTable() {
    373   DCHECK(is_done());
    374   if (info()->ShouldEnsureSpaceForLazyDeopt()) {
    375     // For lazy deoptimization we need space to patch a call after every call.
    376     // Ensure there is always space for such patching, even if the code ends
    377     // in a call.
    378     int target_offset = masm()->pc_offset() + Deoptimizer::patch_size();
    379     while (masm()->pc_offset() < target_offset) {
    380       masm()->nop();
    381     }
    382   }
    383   safepoints_.Emit(masm(), GetTotalFrameSlotCount());
    384   return !is_aborted();
    385 }
    386 
    387 
    388 Register LCodeGen::ToRegister(int code) const {
    389   return Register::from_code(code);
    390 }
    391 
    392 
    393 X87Register LCodeGen::ToX87Register(int code) const {
    394   return X87Register::from_code(code);
    395 }
    396 
    397 
    398 void LCodeGen::X87LoadForUsage(X87Register reg) {
    399   DCHECK(x87_stack_.Contains(reg));
    400   x87_stack_.Fxch(reg);
    401   x87_stack_.pop();
    402 }
    403 
    404 
    405 void LCodeGen::X87LoadForUsage(X87Register reg1, X87Register reg2) {
    406   DCHECK(x87_stack_.Contains(reg1));
    407   DCHECK(x87_stack_.Contains(reg2));
    408   if (reg1.is(reg2) && x87_stack_.depth() == 1) {
    409     __ fld(x87_stack_.st(reg1));
    410     x87_stack_.push(reg1);
    411     x87_stack_.pop();
    412     x87_stack_.pop();
    413   } else {
    414     x87_stack_.Fxch(reg1, 1);
    415     x87_stack_.Fxch(reg2);
    416     x87_stack_.pop();
    417     x87_stack_.pop();
    418   }
    419 }
    420 
    421 
    422 int LCodeGen::X87Stack::GetLayout() {
    423   int layout = stack_depth_;
    424   for (int i = 0; i < stack_depth_; i++) {
    425     layout |= (stack_[stack_depth_ - 1 - i].code() << ((i + 1) * 3));
    426   }
    427 
    428   return layout;
    429 }
    430 
    431 
    432 void LCodeGen::X87Stack::Fxch(X87Register reg, int other_slot) {
    433   DCHECK(is_mutable_);
    434   DCHECK(Contains(reg) && stack_depth_ > other_slot);
    435   int i  = ArrayIndex(reg);
    436   int st = st2idx(i);
    437   if (st != other_slot) {
    438     int other_i = st2idx(other_slot);
    439     X87Register other = stack_[other_i];
    440     stack_[other_i]   = reg;
    441     stack_[i]         = other;
    442     if (st == 0) {
    443       __ fxch(other_slot);
    444     } else if (other_slot == 0) {
    445       __ fxch(st);
    446     } else {
    447       __ fxch(st);
    448       __ fxch(other_slot);
    449       __ fxch(st);
    450     }
    451   }
    452 }
    453 
    454 
    455 int LCodeGen::X87Stack::st2idx(int pos) {
    456   return stack_depth_ - pos - 1;
    457 }
    458 
    459 
    460 int LCodeGen::X87Stack::ArrayIndex(X87Register reg) {
    461   for (int i = 0; i < stack_depth_; i++) {
    462     if (stack_[i].is(reg)) return i;
    463   }
    464   UNREACHABLE();
    465   return -1;
    466 }
    467 
    468 
    469 bool LCodeGen::X87Stack::Contains(X87Register reg) {
    470   for (int i = 0; i < stack_depth_; i++) {
    471     if (stack_[i].is(reg)) return true;
    472   }
    473   return false;
    474 }
    475 
    476 
    477 void LCodeGen::X87Stack::Free(X87Register reg) {
    478   DCHECK(is_mutable_);
    479   DCHECK(Contains(reg));
    480   int i  = ArrayIndex(reg);
    481   int st = st2idx(i);
    482   if (st > 0) {
    483     // keep track of how fstp(i) changes the order of elements
    484     int tos_i = st2idx(0);
    485     stack_[i] = stack_[tos_i];
    486   }
    487   pop();
    488   __ fstp(st);
    489 }
    490 
    491 
    492 void LCodeGen::X87Mov(X87Register dst, Operand src, X87OperandType opts) {
    493   if (x87_stack_.Contains(dst)) {
    494     x87_stack_.Fxch(dst);
    495     __ fstp(0);
    496   } else {
    497     x87_stack_.push(dst);
    498   }
    499   X87Fld(src, opts);
    500 }
    501 
    502 
    503 void LCodeGen::X87Mov(X87Register dst, X87Register src, X87OperandType opts) {
    504   if (x87_stack_.Contains(dst)) {
    505     x87_stack_.Fxch(dst);
    506     __ fstp(0);
    507     x87_stack_.pop();
    508     // Push ST(i) onto the FPU register stack
    509     __ fld(x87_stack_.st(src));
    510     x87_stack_.push(dst);
    511   } else {
    512     // Push ST(i) onto the FPU register stack
    513     __ fld(x87_stack_.st(src));
    514     x87_stack_.push(dst);
    515   }
    516 }
    517 
    518 
    519 void LCodeGen::X87Fld(Operand src, X87OperandType opts) {
    520   DCHECK(!src.is_reg_only());
    521   switch (opts) {
    522     case kX87DoubleOperand:
    523       __ fld_d(src);
    524       break;
    525     case kX87FloatOperand:
    526       __ fld_s(src);
    527       break;
    528     case kX87IntOperand:
    529       __ fild_s(src);
    530       break;
    531     default:
    532       UNREACHABLE();
    533   }
    534 }
    535 
    536 
    537 void LCodeGen::X87Mov(Operand dst, X87Register src, X87OperandType opts) {
    538   DCHECK(!dst.is_reg_only());
    539   x87_stack_.Fxch(src);
    540   switch (opts) {
    541     case kX87DoubleOperand:
    542       __ fst_d(dst);
    543       break;
    544     case kX87FloatOperand:
    545       __ fst_s(dst);
    546       break;
    547     case kX87IntOperand:
    548       __ fist_s(dst);
    549       break;
    550     default:
    551       UNREACHABLE();
    552   }
    553 }
    554 
    555 
    556 void LCodeGen::X87Stack::PrepareToWrite(X87Register reg) {
    557   DCHECK(is_mutable_);
    558   if (Contains(reg)) {
    559     Free(reg);
    560   }
    561   // Mark this register as the next register to write to
    562   stack_[stack_depth_] = reg;
    563 }
    564 
    565 
    566 void LCodeGen::X87Stack::CommitWrite(X87Register reg) {
    567   DCHECK(is_mutable_);
    568   // Assert the reg is prepared to write, but not on the virtual stack yet
    569   DCHECK(!Contains(reg) && stack_[stack_depth_].is(reg) &&
    570          stack_depth_ < X87Register::kMaxNumAllocatableRegisters);
    571   stack_depth_++;
    572 }
    573 
    574 
    575 void LCodeGen::X87PrepareBinaryOp(
    576     X87Register left, X87Register right, X87Register result) {
    577   // You need to use DefineSameAsFirst for x87 instructions
    578   DCHECK(result.is(left));
    579   x87_stack_.Fxch(right, 1);
    580   x87_stack_.Fxch(left);
    581 }
    582 
    583 
    584 void LCodeGen::X87Stack::FlushIfNecessary(LInstruction* instr, LCodeGen* cgen) {
    585   if (stack_depth_ > 0 && instr->ClobbersDoubleRegisters(isolate())) {
    586     bool double_inputs = instr->HasDoubleRegisterInput();
    587 
    588     // Flush stack from tos down, since FreeX87() will mess with tos
    589     for (int i = stack_depth_-1; i >= 0; i--) {
    590       X87Register reg = stack_[i];
    591       // Skip registers which contain the inputs for the next instruction
    592       // when flushing the stack
    593       if (double_inputs && instr->IsDoubleInput(reg, cgen)) {
    594         continue;
    595       }
    596       Free(reg);
    597       if (i < stack_depth_-1) i++;
    598     }
    599   }
    600   if (instr->IsReturn()) {
    601     while (stack_depth_ > 0) {
    602       __ fstp(0);
    603       stack_depth_--;
    604     }
    605     if (FLAG_debug_code && FLAG_enable_slow_asserts) __ VerifyX87StackDepth(0);
    606   }
    607 }
    608 
    609 
    610 void LCodeGen::X87Stack::LeavingBlock(int current_block_id, LGoto* goto_instr,
    611                                       LCodeGen* cgen) {
    612   // For going to a joined block, an explicit LClobberDoubles is inserted before
    613   // LGoto. Because all used x87 registers are spilled to stack slots. The
    614   // ResolvePhis phase of register allocator could guarantee the two input's x87
    615   // stacks have the same layout. So don't check stack_depth_ <= 1 here.
    616   int goto_block_id = goto_instr->block_id();
    617   if (current_block_id + 1 != goto_block_id) {
    618     // If we have a value on the x87 stack on leaving a block, it must be a
    619     // phi input. If the next block we compile is not the join block, we have
    620     // to discard the stack state.
    621     // Before discarding the stack state, we need to save it if the "goto block"
    622     // has unreachable last predecessor when FLAG_unreachable_code_elimination.
    623     if (FLAG_unreachable_code_elimination) {
    624       int length = goto_instr->block()->predecessors()->length();
    625       bool has_unreachable_last_predecessor = false;
    626       for (int i = 0; i < length; i++) {
    627         HBasicBlock* block = goto_instr->block()->predecessors()->at(i);
    628         if (block->IsUnreachable() &&
    629             (block->block_id() + 1) == goto_block_id) {
    630           has_unreachable_last_predecessor = true;
    631         }
    632       }
    633       if (has_unreachable_last_predecessor) {
    634         if (cgen->x87_stack_map_.find(goto_block_id) ==
    635             cgen->x87_stack_map_.end()) {
    636           X87Stack* stack = new (cgen->zone()) X87Stack(*this);
    637           cgen->x87_stack_map_.insert(std::make_pair(goto_block_id, stack));
    638         }
    639       }
    640     }
    641 
    642     // Discard the stack state.
    643     stack_depth_ = 0;
    644   }
    645 }
    646 
    647 
    648 void LCodeGen::EmitFlushX87ForDeopt() {
    649   // The deoptimizer does not support X87 Registers. But as long as we
    650   // deopt from a stub its not a problem, since we will re-materialize the
    651   // original stub inputs, which can't be double registers.
    652   // DCHECK(info()->IsStub());
    653   if (FLAG_debug_code && FLAG_enable_slow_asserts) {
    654     __ pushfd();
    655     __ VerifyX87StackDepth(x87_stack_.depth());
    656     __ popfd();
    657   }
    658 
    659   // Flush X87 stack in the deoptimizer entry.
    660 }
    661 
    662 
    663 Register LCodeGen::ToRegister(LOperand* op) const {
    664   DCHECK(op->IsRegister());
    665   return ToRegister(op->index());
    666 }
    667 
    668 
    669 X87Register LCodeGen::ToX87Register(LOperand* op) const {
    670   DCHECK(op->IsDoubleRegister());
    671   return ToX87Register(op->index());
    672 }
    673 
    674 
    675 int32_t LCodeGen::ToInteger32(LConstantOperand* op) const {
    676   return ToRepresentation(op, Representation::Integer32());
    677 }
    678 
    679 
    680 int32_t LCodeGen::ToRepresentation(LConstantOperand* op,
    681                                    const Representation& r) const {
    682   HConstant* constant = chunk_->LookupConstant(op);
    683   if (r.IsExternal()) {
    684     return reinterpret_cast<int32_t>(
    685         constant->ExternalReferenceValue().address());
    686   }
    687   int32_t value = constant->Integer32Value();
    688   if (r.IsInteger32()) return value;
    689   DCHECK(r.IsSmiOrTagged());
    690   return reinterpret_cast<int32_t>(Smi::FromInt(value));
    691 }
    692 
    693 
    694 Handle<Object> LCodeGen::ToHandle(LConstantOperand* op) const {
    695   HConstant* constant = chunk_->LookupConstant(op);
    696   DCHECK(chunk_->LookupLiteralRepresentation(op).IsSmiOrTagged());
    697   return constant->handle(isolate());
    698 }
    699 
    700 
    701 double LCodeGen::ToDouble(LConstantOperand* op) const {
    702   HConstant* constant = chunk_->LookupConstant(op);
    703   DCHECK(constant->HasDoubleValue());
    704   return constant->DoubleValue();
    705 }
    706 
    707 
    708 ExternalReference LCodeGen::ToExternalReference(LConstantOperand* op) const {
    709   HConstant* constant = chunk_->LookupConstant(op);
    710   DCHECK(constant->HasExternalReferenceValue());
    711   return constant->ExternalReferenceValue();
    712 }
    713 
    714 
    715 bool LCodeGen::IsInteger32(LConstantOperand* op) const {
    716   return chunk_->LookupLiteralRepresentation(op).IsSmiOrInteger32();
    717 }
    718 
    719 
    720 bool LCodeGen::IsSmi(LConstantOperand* op) const {
    721   return chunk_->LookupLiteralRepresentation(op).IsSmi();
    722 }
    723 
    724 
    725 static int ArgumentsOffsetWithoutFrame(int index) {
    726   DCHECK(index < 0);
    727   return -(index + 1) * kPointerSize + kPCOnStackSize;
    728 }
    729 
    730 
    731 Operand LCodeGen::ToOperand(LOperand* op) const {
    732   if (op->IsRegister()) return Operand(ToRegister(op));
    733   DCHECK(!op->IsDoubleRegister());
    734   DCHECK(op->IsStackSlot() || op->IsDoubleStackSlot());
    735   if (NeedsEagerFrame()) {
    736     return Operand(ebp, FrameSlotToFPOffset(op->index()));
    737   } else {
    738     // Retrieve parameter without eager stack-frame relative to the
    739     // stack-pointer.
    740     return Operand(esp, ArgumentsOffsetWithoutFrame(op->index()));
    741   }
    742 }
    743 
    744 
    745 Operand LCodeGen::HighOperand(LOperand* op) {
    746   DCHECK(op->IsDoubleStackSlot());
    747   if (NeedsEagerFrame()) {
    748     return Operand(ebp, FrameSlotToFPOffset(op->index()) + kPointerSize);
    749   } else {
    750     // Retrieve parameter without eager stack-frame relative to the
    751     // stack-pointer.
    752     return Operand(
    753         esp, ArgumentsOffsetWithoutFrame(op->index()) + kPointerSize);
    754   }
    755 }
    756 
    757 
    758 void LCodeGen::WriteTranslation(LEnvironment* environment,
    759                                 Translation* translation) {
    760   if (environment == NULL) return;
    761 
    762   // The translation includes one command per value in the environment.
    763   int translation_size = environment->translation_size();
    764 
    765   WriteTranslation(environment->outer(), translation);
    766   WriteTranslationFrame(environment, translation);
    767 
    768   int object_index = 0;
    769   int dematerialized_index = 0;
    770   for (int i = 0; i < translation_size; ++i) {
    771     LOperand* value = environment->values()->at(i);
    772     AddToTranslation(environment,
    773                      translation,
    774                      value,
    775                      environment->HasTaggedValueAt(i),
    776                      environment->HasUint32ValueAt(i),
    777                      &object_index,
    778                      &dematerialized_index);
    779   }
    780 }
    781 
    782 
    783 void LCodeGen::AddToTranslation(LEnvironment* environment,
    784                                 Translation* translation,
    785                                 LOperand* op,
    786                                 bool is_tagged,
    787                                 bool is_uint32,
    788                                 int* object_index_pointer,
    789                                 int* dematerialized_index_pointer) {
    790   if (op == LEnvironment::materialization_marker()) {
    791     int object_index = (*object_index_pointer)++;
    792     if (environment->ObjectIsDuplicateAt(object_index)) {
    793       int dupe_of = environment->ObjectDuplicateOfAt(object_index);
    794       translation->DuplicateObject(dupe_of);
    795       return;
    796     }
    797     int object_length = environment->ObjectLengthAt(object_index);
    798     if (environment->ObjectIsArgumentsAt(object_index)) {
    799       translation->BeginArgumentsObject(object_length);
    800     } else {
    801       translation->BeginCapturedObject(object_length);
    802     }
    803     int dematerialized_index = *dematerialized_index_pointer;
    804     int env_offset = environment->translation_size() + dematerialized_index;
    805     *dematerialized_index_pointer += object_length;
    806     for (int i = 0; i < object_length; ++i) {
    807       LOperand* value = environment->values()->at(env_offset + i);
    808       AddToTranslation(environment,
    809                        translation,
    810                        value,
    811                        environment->HasTaggedValueAt(env_offset + i),
    812                        environment->HasUint32ValueAt(env_offset + i),
    813                        object_index_pointer,
    814                        dematerialized_index_pointer);
    815     }
    816     return;
    817   }
    818 
    819   if (op->IsStackSlot()) {
    820     int index = op->index();
    821     if (is_tagged) {
    822       translation->StoreStackSlot(index);
    823     } else if (is_uint32) {
    824       translation->StoreUint32StackSlot(index);
    825     } else {
    826       translation->StoreInt32StackSlot(index);
    827     }
    828   } else if (op->IsDoubleStackSlot()) {
    829     int index = op->index();
    830     translation->StoreDoubleStackSlot(index);
    831   } else if (op->IsRegister()) {
    832     Register reg = ToRegister(op);
    833     if (is_tagged) {
    834       translation->StoreRegister(reg);
    835     } else if (is_uint32) {
    836       translation->StoreUint32Register(reg);
    837     } else {
    838       translation->StoreInt32Register(reg);
    839     }
    840   } else if (op->IsDoubleRegister()) {
    841     X87Register reg = ToX87Register(op);
    842     translation->StoreDoubleRegister(reg);
    843   } else if (op->IsConstantOperand()) {
    844     HConstant* constant = chunk()->LookupConstant(LConstantOperand::cast(op));
    845     int src_index = DefineDeoptimizationLiteral(constant->handle(isolate()));
    846     translation->StoreLiteral(src_index);
    847   } else {
    848     UNREACHABLE();
    849   }
    850 }
    851 
    852 
    853 void LCodeGen::CallCodeGeneric(Handle<Code> code,
    854                                RelocInfo::Mode mode,
    855                                LInstruction* instr,
    856                                SafepointMode safepoint_mode) {
    857   DCHECK(instr != NULL);
    858   __ call(code, mode);
    859   RecordSafepointWithLazyDeopt(instr, safepoint_mode);
    860 
    861   // Signal that we don't inline smi code before these stubs in the
    862   // optimizing code generator.
    863   if (code->kind() == Code::BINARY_OP_IC ||
    864       code->kind() == Code::COMPARE_IC) {
    865     __ nop();
    866   }
    867 }
    868 
    869 
    870 void LCodeGen::CallCode(Handle<Code> code,
    871                         RelocInfo::Mode mode,
    872                         LInstruction* instr) {
    873   CallCodeGeneric(code, mode, instr, RECORD_SIMPLE_SAFEPOINT);
    874 }
    875 
    876 
    877 void LCodeGen::CallRuntime(const Runtime::Function* fun, int argc,
    878                            LInstruction* instr, SaveFPRegsMode save_doubles) {
    879   DCHECK(instr != NULL);
    880   DCHECK(instr->HasPointerMap());
    881 
    882   __ CallRuntime(fun, argc, save_doubles);
    883 
    884   RecordSafepointWithLazyDeopt(instr, RECORD_SIMPLE_SAFEPOINT);
    885 
    886   DCHECK(info()->is_calling());
    887 }
    888 
    889 
    890 void LCodeGen::LoadContextFromDeferred(LOperand* context) {
    891   if (context->IsRegister()) {
    892     if (!ToRegister(context).is(esi)) {
    893       __ mov(esi, ToRegister(context));
    894     }
    895   } else if (context->IsStackSlot()) {
    896     __ mov(esi, ToOperand(context));
    897   } else if (context->IsConstantOperand()) {
    898     HConstant* constant =
    899         chunk_->LookupConstant(LConstantOperand::cast(context));
    900     __ LoadObject(esi, Handle<Object>::cast(constant->handle(isolate())));
    901   } else {
    902     UNREACHABLE();
    903   }
    904 }
    905 
    906 void LCodeGen::CallRuntimeFromDeferred(Runtime::FunctionId id,
    907                                        int argc,
    908                                        LInstruction* instr,
    909                                        LOperand* context) {
    910   LoadContextFromDeferred(context);
    911 
    912   __ CallRuntimeSaveDoubles(id);
    913   RecordSafepointWithRegisters(
    914       instr->pointer_map(), argc, Safepoint::kNoLazyDeopt);
    915 
    916   DCHECK(info()->is_calling());
    917 }
    918 
    919 
    920 void LCodeGen::RegisterEnvironmentForDeoptimization(
    921     LEnvironment* environment, Safepoint::DeoptMode mode) {
    922   environment->set_has_been_used();
    923   if (!environment->HasBeenRegistered()) {
    924     // Physical stack frame layout:
    925     // -x ............. -4  0 ..................................... y
    926     // [incoming arguments] [spill slots] [pushed outgoing arguments]
    927 
    928     // Layout of the environment:
    929     // 0 ..................................................... size-1
    930     // [parameters] [locals] [expression stack including arguments]
    931 
    932     // Layout of the translation:
    933     // 0 ........................................................ size - 1 + 4
    934     // [expression stack including arguments] [locals] [4 words] [parameters]
    935     // |>------------  translation_size ------------<|
    936 
    937     int frame_count = 0;
    938     int jsframe_count = 0;
    939     for (LEnvironment* e = environment; e != NULL; e = e->outer()) {
    940       ++frame_count;
    941       if (e->frame_type() == JS_FUNCTION) {
    942         ++jsframe_count;
    943       }
    944     }
    945     Translation translation(&translations_, frame_count, jsframe_count, zone());
    946     WriteTranslation(environment, &translation);
    947     int deoptimization_index = deoptimizations_.length();
    948     int pc_offset = masm()->pc_offset();
    949     environment->Register(deoptimization_index,
    950                           translation.index(),
    951                           (mode == Safepoint::kLazyDeopt) ? pc_offset : -1);
    952     deoptimizations_.Add(environment, zone());
    953   }
    954 }
    955 
    956 void LCodeGen::DeoptimizeIf(Condition cc, LInstruction* instr,
    957                             DeoptimizeReason deopt_reason,
    958                             Deoptimizer::BailoutType bailout_type) {
    959   LEnvironment* environment = instr->environment();
    960   RegisterEnvironmentForDeoptimization(environment, Safepoint::kNoLazyDeopt);
    961   DCHECK(environment->HasBeenRegistered());
    962   int id = environment->deoptimization_index();
    963   Address entry =
    964       Deoptimizer::GetDeoptimizationEntry(isolate(), id, bailout_type);
    965   if (entry == NULL) {
    966     Abort(kBailoutWasNotPrepared);
    967     return;
    968   }
    969 
    970   if (DeoptEveryNTimes()) {
    971     ExternalReference count = ExternalReference::stress_deopt_count(isolate());
    972     Label no_deopt;
    973     __ pushfd();
    974     __ push(eax);
    975     __ mov(eax, Operand::StaticVariable(count));
    976     __ sub(eax, Immediate(1));
    977     __ j(not_zero, &no_deopt, Label::kNear);
    978     if (FLAG_trap_on_deopt) __ int3();
    979     __ mov(eax, Immediate(FLAG_deopt_every_n_times));
    980     __ mov(Operand::StaticVariable(count), eax);
    981     __ pop(eax);
    982     __ popfd();
    983     DCHECK(frame_is_built_);
    984     // Put the x87 stack layout in TOS.
    985     if (x87_stack_.depth() > 0) EmitFlushX87ForDeopt();
    986     __ push(Immediate(x87_stack_.GetLayout()));
    987     __ fild_s(MemOperand(esp, 0));
    988     // Don't touch eflags.
    989     __ lea(esp, Operand(esp, kPointerSize));
    990     __ call(entry, RelocInfo::RUNTIME_ENTRY);
    991     __ bind(&no_deopt);
    992     __ mov(Operand::StaticVariable(count), eax);
    993     __ pop(eax);
    994     __ popfd();
    995   }
    996 
    997   // Put the x87 stack layout in TOS, so that we can save x87 fp registers in
    998   // the correct location.
    999   {
   1000     Label done;
   1001     if (cc != no_condition) __ j(NegateCondition(cc), &done, Label::kNear);
   1002     if (x87_stack_.depth() > 0) EmitFlushX87ForDeopt();
   1003 
   1004     int x87_stack_layout = x87_stack_.GetLayout();
   1005     __ push(Immediate(x87_stack_layout));
   1006     __ fild_s(MemOperand(esp, 0));
   1007     // Don't touch eflags.
   1008     __ lea(esp, Operand(esp, kPointerSize));
   1009     __ bind(&done);
   1010   }
   1011 
   1012   if (info()->ShouldTrapOnDeopt()) {
   1013     Label done;
   1014     if (cc != no_condition) __ j(NegateCondition(cc), &done, Label::kNear);
   1015     __ int3();
   1016     __ bind(&done);
   1017   }
   1018 
   1019   Deoptimizer::DeoptInfo deopt_info = MakeDeoptInfo(instr, deopt_reason, id);
   1020 
   1021   DCHECK(info()->IsStub() || frame_is_built_);
   1022   if (cc == no_condition && frame_is_built_) {
   1023     DeoptComment(deopt_info);
   1024     __ call(entry, RelocInfo::RUNTIME_ENTRY);
   1025   } else {
   1026     Deoptimizer::JumpTableEntry table_entry(entry, deopt_info, bailout_type,
   1027                                             !frame_is_built_);
   1028     // We often have several deopts to the same entry, reuse the last
   1029     // jump entry if this is the case.
   1030     if (FLAG_trace_deopt || isolate()->is_profiling() ||
   1031         jump_table_.is_empty() ||
   1032         !table_entry.IsEquivalentTo(jump_table_.last())) {
   1033       jump_table_.Add(table_entry, zone());
   1034     }
   1035     if (cc == no_condition) {
   1036       __ jmp(&jump_table_.last().label);
   1037     } else {
   1038       __ j(cc, &jump_table_.last().label);
   1039     }
   1040   }
   1041 }
   1042 
   1043 void LCodeGen::DeoptimizeIf(Condition cc, LInstruction* instr,
   1044                             DeoptimizeReason deopt_reason) {
   1045   Deoptimizer::BailoutType bailout_type = info()->IsStub()
   1046       ? Deoptimizer::LAZY
   1047       : Deoptimizer::EAGER;
   1048   DeoptimizeIf(cc, instr, deopt_reason, bailout_type);
   1049 }
   1050 
   1051 
   1052 void LCodeGen::RecordSafepointWithLazyDeopt(
   1053     LInstruction* instr, SafepointMode safepoint_mode) {
   1054   if (safepoint_mode == RECORD_SIMPLE_SAFEPOINT) {
   1055     RecordSafepoint(instr->pointer_map(), Safepoint::kLazyDeopt);
   1056   } else {
   1057     DCHECK(safepoint_mode == RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS);
   1058     RecordSafepointWithRegisters(
   1059         instr->pointer_map(), 0, Safepoint::kLazyDeopt);
   1060   }
   1061 }
   1062 
   1063 
   1064 void LCodeGen::RecordSafepoint(
   1065     LPointerMap* pointers,
   1066     Safepoint::Kind kind,
   1067     int arguments,
   1068     Safepoint::DeoptMode deopt_mode) {
   1069   DCHECK(kind == expected_safepoint_kind_);
   1070   const ZoneList<LOperand*>* operands = pointers->GetNormalizedOperands();
   1071   Safepoint safepoint =
   1072       safepoints_.DefineSafepoint(masm(), kind, arguments, deopt_mode);
   1073   for (int i = 0; i < operands->length(); i++) {
   1074     LOperand* pointer = operands->at(i);
   1075     if (pointer->IsStackSlot()) {
   1076       safepoint.DefinePointerSlot(pointer->index(), zone());
   1077     } else if (pointer->IsRegister() && (kind & Safepoint::kWithRegisters)) {
   1078       safepoint.DefinePointerRegister(ToRegister(pointer), zone());
   1079     }
   1080   }
   1081 }
   1082 
   1083 
   1084 void LCodeGen::RecordSafepoint(LPointerMap* pointers,
   1085                                Safepoint::DeoptMode mode) {
   1086   RecordSafepoint(pointers, Safepoint::kSimple, 0, mode);
   1087 }
   1088 
   1089 
   1090 void LCodeGen::RecordSafepoint(Safepoint::DeoptMode mode) {
   1091   LPointerMap empty_pointers(zone());
   1092   RecordSafepoint(&empty_pointers, mode);
   1093 }
   1094 
   1095 
   1096 void LCodeGen::RecordSafepointWithRegisters(LPointerMap* pointers,
   1097                                             int arguments,
   1098                                             Safepoint::DeoptMode mode) {
   1099   RecordSafepoint(pointers, Safepoint::kWithRegisters, arguments, mode);
   1100 }
   1101 
   1102 
   1103 static const char* LabelType(LLabel* label) {
   1104   if (label->is_loop_header()) return " (loop header)";
   1105   if (label->is_osr_entry()) return " (OSR entry)";
   1106   return "";
   1107 }
   1108 
   1109 
   1110 void LCodeGen::DoLabel(LLabel* label) {
   1111   Comment(";;; <@%d,#%d> -------------------- B%d%s --------------------",
   1112           current_instruction_,
   1113           label->hydrogen_value()->id(),
   1114           label->block_id(),
   1115           LabelType(label));
   1116   __ bind(label->label());
   1117   current_block_ = label->block_id();
   1118   if (label->block()->predecessors()->length() > 1) {
   1119     // A join block's x87 stack is that of its last visited predecessor.
   1120     // If the last visited predecessor block is unreachable, the stack state
   1121     // will be wrong. In such case, use the x87 stack of reachable predecessor.
   1122     X87StackMap::const_iterator it = x87_stack_map_.find(current_block_);
   1123     // Restore x87 stack.
   1124     if (it != x87_stack_map_.end()) {
   1125       x87_stack_ = *(it->second);
   1126     }
   1127   }
   1128   DoGap(label);
   1129 }
   1130 
   1131 
   1132 void LCodeGen::DoParallelMove(LParallelMove* move) {
   1133   resolver_.Resolve(move);
   1134 }
   1135 
   1136 
   1137 void LCodeGen::DoGap(LGap* gap) {
   1138   for (int i = LGap::FIRST_INNER_POSITION;
   1139        i <= LGap::LAST_INNER_POSITION;
   1140        i++) {
   1141     LGap::InnerPosition inner_pos = static_cast<LGap::InnerPosition>(i);
   1142     LParallelMove* move = gap->GetParallelMove(inner_pos);
   1143     if (move != NULL) DoParallelMove(move);
   1144   }
   1145 }
   1146 
   1147 
   1148 void LCodeGen::DoInstructionGap(LInstructionGap* instr) {
   1149   DoGap(instr);
   1150 }
   1151 
   1152 
   1153 void LCodeGen::DoParameter(LParameter* instr) {
   1154   // Nothing to do.
   1155 }
   1156 
   1157 
   1158 void LCodeGen::DoUnknownOSRValue(LUnknownOSRValue* instr) {
   1159   GenerateOsrPrologue();
   1160 }
   1161 
   1162 
   1163 void LCodeGen::DoModByPowerOf2I(LModByPowerOf2I* instr) {
   1164   Register dividend = ToRegister(instr->dividend());
   1165   int32_t divisor = instr->divisor();
   1166   DCHECK(dividend.is(ToRegister(instr->result())));
   1167 
   1168   // Theoretically, a variation of the branch-free code for integer division by
   1169   // a power of 2 (calculating the remainder via an additional multiplication
   1170   // (which gets simplified to an 'and') and subtraction) should be faster, and
   1171   // this is exactly what GCC and clang emit. Nevertheless, benchmarks seem to
   1172   // indicate that positive dividends are heavily favored, so the branching
   1173   // version performs better.
   1174   HMod* hmod = instr->hydrogen();
   1175   int32_t mask = divisor < 0 ? -(divisor + 1) : (divisor - 1);
   1176   Label dividend_is_not_negative, done;
   1177   if (hmod->CheckFlag(HValue::kLeftCanBeNegative)) {
   1178     __ test(dividend, dividend);
   1179     __ j(not_sign, &dividend_is_not_negative, Label::kNear);
   1180     // Note that this is correct even for kMinInt operands.
   1181     __ neg(dividend);
   1182     __ and_(dividend, mask);
   1183     __ neg(dividend);
   1184     if (hmod->CheckFlag(HValue::kBailoutOnMinusZero)) {
   1185       DeoptimizeIf(zero, instr, DeoptimizeReason::kMinusZero);
   1186     }
   1187     __ jmp(&done, Label::kNear);
   1188   }
   1189 
   1190   __ bind(&dividend_is_not_negative);
   1191   __ and_(dividend, mask);
   1192   __ bind(&done);
   1193 }
   1194 
   1195 
   1196 void LCodeGen::DoModByConstI(LModByConstI* instr) {
   1197   Register dividend = ToRegister(instr->dividend());
   1198   int32_t divisor = instr->divisor();
   1199   DCHECK(ToRegister(instr->result()).is(eax));
   1200 
   1201   if (divisor == 0) {
   1202     DeoptimizeIf(no_condition, instr, DeoptimizeReason::kDivisionByZero);
   1203     return;
   1204   }
   1205 
   1206   __ TruncatingDiv(dividend, Abs(divisor));
   1207   __ imul(edx, edx, Abs(divisor));
   1208   __ mov(eax, dividend);
   1209   __ sub(eax, edx);
   1210 
   1211   // Check for negative zero.
   1212   HMod* hmod = instr->hydrogen();
   1213   if (hmod->CheckFlag(HValue::kBailoutOnMinusZero)) {
   1214     Label remainder_not_zero;
   1215     __ j(not_zero, &remainder_not_zero, Label::kNear);
   1216     __ cmp(dividend, Immediate(0));
   1217     DeoptimizeIf(less, instr, DeoptimizeReason::kMinusZero);
   1218     __ bind(&remainder_not_zero);
   1219   }
   1220 }
   1221 
   1222 
   1223 void LCodeGen::DoModI(LModI* instr) {
   1224   HMod* hmod = instr->hydrogen();
   1225 
   1226   Register left_reg = ToRegister(instr->left());
   1227   DCHECK(left_reg.is(eax));
   1228   Register right_reg = ToRegister(instr->right());
   1229   DCHECK(!right_reg.is(eax));
   1230   DCHECK(!right_reg.is(edx));
   1231   Register result_reg = ToRegister(instr->result());
   1232   DCHECK(result_reg.is(edx));
   1233 
   1234   Label done;
   1235   // Check for x % 0, idiv would signal a divide error. We have to
   1236   // deopt in this case because we can't return a NaN.
   1237   if (hmod->CheckFlag(HValue::kCanBeDivByZero)) {
   1238     __ test(right_reg, Operand(right_reg));
   1239     DeoptimizeIf(zero, instr, DeoptimizeReason::kDivisionByZero);
   1240   }
   1241 
   1242   // Check for kMinInt % -1, idiv would signal a divide error. We
   1243   // have to deopt if we care about -0, because we can't return that.
   1244   if (hmod->CheckFlag(HValue::kCanOverflow)) {
   1245     Label no_overflow_possible;
   1246     __ cmp(left_reg, kMinInt);
   1247     __ j(not_equal, &no_overflow_possible, Label::kNear);
   1248     __ cmp(right_reg, -1);
   1249     if (hmod->CheckFlag(HValue::kBailoutOnMinusZero)) {
   1250       DeoptimizeIf(equal, instr, DeoptimizeReason::kMinusZero);
   1251     } else {
   1252       __ j(not_equal, &no_overflow_possible, Label::kNear);
   1253       __ Move(result_reg, Immediate(0));
   1254       __ jmp(&done, Label::kNear);
   1255     }
   1256     __ bind(&no_overflow_possible);
   1257   }
   1258 
   1259   // Sign extend dividend in eax into edx:eax.
   1260   __ cdq();
   1261 
   1262   // If we care about -0, test if the dividend is <0 and the result is 0.
   1263   if (hmod->CheckFlag(HValue::kBailoutOnMinusZero)) {
   1264     Label positive_left;
   1265     __ test(left_reg, Operand(left_reg));
   1266     __ j(not_sign, &positive_left, Label::kNear);
   1267     __ idiv(right_reg);
   1268     __ test(result_reg, Operand(result_reg));
   1269     DeoptimizeIf(zero, instr, DeoptimizeReason::kMinusZero);
   1270     __ jmp(&done, Label::kNear);
   1271     __ bind(&positive_left);
   1272   }
   1273   __ idiv(right_reg);
   1274   __ bind(&done);
   1275 }
   1276 
   1277 
   1278 void LCodeGen::DoDivByPowerOf2I(LDivByPowerOf2I* instr) {
   1279   Register dividend = ToRegister(instr->dividend());
   1280   int32_t divisor = instr->divisor();
   1281   Register result = ToRegister(instr->result());
   1282   DCHECK(divisor == kMinInt || base::bits::IsPowerOfTwo32(Abs(divisor)));
   1283   DCHECK(!result.is(dividend));
   1284 
   1285   // Check for (0 / -x) that will produce negative zero.
   1286   HDiv* hdiv = instr->hydrogen();
   1287   if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero) && divisor < 0) {
   1288     __ test(dividend, dividend);
   1289     DeoptimizeIf(zero, instr, DeoptimizeReason::kMinusZero);
   1290   }
   1291   // Check for (kMinInt / -1).
   1292   if (hdiv->CheckFlag(HValue::kCanOverflow) && divisor == -1) {
   1293     __ cmp(dividend, kMinInt);
   1294     DeoptimizeIf(zero, instr, DeoptimizeReason::kOverflow);
   1295   }
   1296   // Deoptimize if remainder will not be 0.
   1297   if (!hdiv->CheckFlag(HInstruction::kAllUsesTruncatingToInt32) &&
   1298       divisor != 1 && divisor != -1) {
   1299     int32_t mask = divisor < 0 ? -(divisor + 1) : (divisor - 1);
   1300     __ test(dividend, Immediate(mask));
   1301     DeoptimizeIf(not_zero, instr, DeoptimizeReason::kLostPrecision);
   1302   }
   1303   __ Move(result, dividend);
   1304   int32_t shift = WhichPowerOf2Abs(divisor);
   1305   if (shift > 0) {
   1306     // The arithmetic shift is always OK, the 'if' is an optimization only.
   1307     if (shift > 1) __ sar(result, 31);
   1308     __ shr(result, 32 - shift);
   1309     __ add(result, dividend);
   1310     __ sar(result, shift);
   1311   }
   1312   if (divisor < 0) __ neg(result);
   1313 }
   1314 
   1315 
   1316 void LCodeGen::DoDivByConstI(LDivByConstI* instr) {
   1317   Register dividend = ToRegister(instr->dividend());
   1318   int32_t divisor = instr->divisor();
   1319   DCHECK(ToRegister(instr->result()).is(edx));
   1320 
   1321   if (divisor == 0) {
   1322     DeoptimizeIf(no_condition, instr, DeoptimizeReason::kDivisionByZero);
   1323     return;
   1324   }
   1325 
   1326   // Check for (0 / -x) that will produce negative zero.
   1327   HDiv* hdiv = instr->hydrogen();
   1328   if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero) && divisor < 0) {
   1329     __ test(dividend, dividend);
   1330     DeoptimizeIf(zero, instr, DeoptimizeReason::kMinusZero);
   1331   }
   1332 
   1333   __ TruncatingDiv(dividend, Abs(divisor));
   1334   if (divisor < 0) __ neg(edx);
   1335 
   1336   if (!hdiv->CheckFlag(HInstruction::kAllUsesTruncatingToInt32)) {
   1337     __ mov(eax, edx);
   1338     __ imul(eax, eax, divisor);
   1339     __ sub(eax, dividend);
   1340     DeoptimizeIf(not_equal, instr, DeoptimizeReason::kLostPrecision);
   1341   }
   1342 }
   1343 
   1344 
   1345 // TODO(svenpanne) Refactor this to avoid code duplication with DoFlooringDivI.
   1346 void LCodeGen::DoDivI(LDivI* instr) {
   1347   HBinaryOperation* hdiv = instr->hydrogen();
   1348   Register dividend = ToRegister(instr->dividend());
   1349   Register divisor = ToRegister(instr->divisor());
   1350   Register remainder = ToRegister(instr->temp());
   1351   DCHECK(dividend.is(eax));
   1352   DCHECK(remainder.is(edx));
   1353   DCHECK(ToRegister(instr->result()).is(eax));
   1354   DCHECK(!divisor.is(eax));
   1355   DCHECK(!divisor.is(edx));
   1356 
   1357   // Check for x / 0.
   1358   if (hdiv->CheckFlag(HValue::kCanBeDivByZero)) {
   1359     __ test(divisor, divisor);
   1360     DeoptimizeIf(zero, instr, DeoptimizeReason::kDivisionByZero);
   1361   }
   1362 
   1363   // Check for (0 / -x) that will produce negative zero.
   1364   if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero)) {
   1365     Label dividend_not_zero;
   1366     __ test(dividend, dividend);
   1367     __ j(not_zero, &dividend_not_zero, Label::kNear);
   1368     __ test(divisor, divisor);
   1369     DeoptimizeIf(sign, instr, DeoptimizeReason::kMinusZero);
   1370     __ bind(&dividend_not_zero);
   1371   }
   1372 
   1373   // Check for (kMinInt / -1).
   1374   if (hdiv->CheckFlag(HValue::kCanOverflow)) {
   1375     Label dividend_not_min_int;
   1376     __ cmp(dividend, kMinInt);
   1377     __ j(not_zero, &dividend_not_min_int, Label::kNear);
   1378     __ cmp(divisor, -1);
   1379     DeoptimizeIf(zero, instr, DeoptimizeReason::kOverflow);
   1380     __ bind(&dividend_not_min_int);
   1381   }
   1382 
   1383   // Sign extend to edx (= remainder).
   1384   __ cdq();
   1385   __ idiv(divisor);
   1386 
   1387   if (!hdiv->CheckFlag(HValue::kAllUsesTruncatingToInt32)) {
   1388     // Deoptimize if remainder is not 0.
   1389     __ test(remainder, remainder);
   1390     DeoptimizeIf(not_zero, instr, DeoptimizeReason::kLostPrecision);
   1391   }
   1392 }
   1393 
   1394 
   1395 void LCodeGen::DoFlooringDivByPowerOf2I(LFlooringDivByPowerOf2I* instr) {
   1396   Register dividend = ToRegister(instr->dividend());
   1397   int32_t divisor = instr->divisor();
   1398   DCHECK(dividend.is(ToRegister(instr->result())));
   1399 
   1400   // If the divisor is positive, things are easy: There can be no deopts and we
   1401   // can simply do an arithmetic right shift.
   1402   if (divisor == 1) return;
   1403   int32_t shift = WhichPowerOf2Abs(divisor);
   1404   if (divisor > 1) {
   1405     __ sar(dividend, shift);
   1406     return;
   1407   }
   1408 
   1409   // If the divisor is negative, we have to negate and handle edge cases.
   1410   __ neg(dividend);
   1411   if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
   1412     DeoptimizeIf(zero, instr, DeoptimizeReason::kMinusZero);
   1413   }
   1414 
   1415   // Dividing by -1 is basically negation, unless we overflow.
   1416   if (divisor == -1) {
   1417     if (instr->hydrogen()->CheckFlag(HValue::kLeftCanBeMinInt)) {
   1418       DeoptimizeIf(overflow, instr, DeoptimizeReason::kOverflow);
   1419     }
   1420     return;
   1421   }
   1422 
   1423   // If the negation could not overflow, simply shifting is OK.
   1424   if (!instr->hydrogen()->CheckFlag(HValue::kLeftCanBeMinInt)) {
   1425     __ sar(dividend, shift);
   1426     return;
   1427   }
   1428 
   1429   Label not_kmin_int, done;
   1430   __ j(no_overflow, &not_kmin_int, Label::kNear);
   1431   __ mov(dividend, Immediate(kMinInt / divisor));
   1432   __ jmp(&done, Label::kNear);
   1433   __ bind(&not_kmin_int);
   1434   __ sar(dividend, shift);
   1435   __ bind(&done);
   1436 }
   1437 
   1438 
   1439 void LCodeGen::DoFlooringDivByConstI(LFlooringDivByConstI* instr) {
   1440   Register dividend = ToRegister(instr->dividend());
   1441   int32_t divisor = instr->divisor();
   1442   DCHECK(ToRegister(instr->result()).is(edx));
   1443 
   1444   if (divisor == 0) {
   1445     DeoptimizeIf(no_condition, instr, DeoptimizeReason::kDivisionByZero);
   1446     return;
   1447   }
   1448 
   1449   // Check for (0 / -x) that will produce negative zero.
   1450   HMathFloorOfDiv* hdiv = instr->hydrogen();
   1451   if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero) && divisor < 0) {
   1452     __ test(dividend, dividend);
   1453     DeoptimizeIf(zero, instr, DeoptimizeReason::kMinusZero);
   1454   }
   1455 
   1456   // Easy case: We need no dynamic check for the dividend and the flooring
   1457   // division is the same as the truncating division.
   1458   if ((divisor > 0 && !hdiv->CheckFlag(HValue::kLeftCanBeNegative)) ||
   1459       (divisor < 0 && !hdiv->CheckFlag(HValue::kLeftCanBePositive))) {
   1460     __ TruncatingDiv(dividend, Abs(divisor));
   1461     if (divisor < 0) __ neg(edx);
   1462     return;
   1463   }
   1464 
   1465   // In the general case we may need to adjust before and after the truncating
   1466   // division to get a flooring division.
   1467   Register temp = ToRegister(instr->temp3());
   1468   DCHECK(!temp.is(dividend) && !temp.is(eax) && !temp.is(edx));
   1469   Label needs_adjustment, done;
   1470   __ cmp(dividend, Immediate(0));
   1471   __ j(divisor > 0 ? less : greater, &needs_adjustment, Label::kNear);
   1472   __ TruncatingDiv(dividend, Abs(divisor));
   1473   if (divisor < 0) __ neg(edx);
   1474   __ jmp(&done, Label::kNear);
   1475   __ bind(&needs_adjustment);
   1476   __ lea(temp, Operand(dividend, divisor > 0 ? 1 : -1));
   1477   __ TruncatingDiv(temp, Abs(divisor));
   1478   if (divisor < 0) __ neg(edx);
   1479   __ dec(edx);
   1480   __ bind(&done);
   1481 }
   1482 
   1483 
   1484 // TODO(svenpanne) Refactor this to avoid code duplication with DoDivI.
   1485 void LCodeGen::DoFlooringDivI(LFlooringDivI* instr) {
   1486   HBinaryOperation* hdiv = instr->hydrogen();
   1487   Register dividend = ToRegister(instr->dividend());
   1488   Register divisor = ToRegister(instr->divisor());
   1489   Register remainder = ToRegister(instr->temp());
   1490   Register result = ToRegister(instr->result());
   1491   DCHECK(dividend.is(eax));
   1492   DCHECK(remainder.is(edx));
   1493   DCHECK(result.is(eax));
   1494   DCHECK(!divisor.is(eax));
   1495   DCHECK(!divisor.is(edx));
   1496 
   1497   // Check for x / 0.
   1498   if (hdiv->CheckFlag(HValue::kCanBeDivByZero)) {
   1499     __ test(divisor, divisor);
   1500     DeoptimizeIf(zero, instr, DeoptimizeReason::kDivisionByZero);
   1501   }
   1502 
   1503   // Check for (0 / -x) that will produce negative zero.
   1504   if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero)) {
   1505     Label dividend_not_zero;
   1506     __ test(dividend, dividend);
   1507     __ j(not_zero, &dividend_not_zero, Label::kNear);
   1508     __ test(divisor, divisor);
   1509     DeoptimizeIf(sign, instr, DeoptimizeReason::kMinusZero);
   1510     __ bind(&dividend_not_zero);
   1511   }
   1512 
   1513   // Check for (kMinInt / -1).
   1514   if (hdiv->CheckFlag(HValue::kCanOverflow)) {
   1515     Label dividend_not_min_int;
   1516     __ cmp(dividend, kMinInt);
   1517     __ j(not_zero, &dividend_not_min_int, Label::kNear);
   1518     __ cmp(divisor, -1);
   1519     DeoptimizeIf(zero, instr, DeoptimizeReason::kOverflow);
   1520     __ bind(&dividend_not_min_int);
   1521   }
   1522 
   1523   // Sign extend to edx (= remainder).
   1524   __ cdq();
   1525   __ idiv(divisor);
   1526 
   1527   Label done;
   1528   __ test(remainder, remainder);
   1529   __ j(zero, &done, Label::kNear);
   1530   __ xor_(remainder, divisor);
   1531   __ sar(remainder, 31);
   1532   __ add(result, remainder);
   1533   __ bind(&done);
   1534 }
   1535 
   1536 
   1537 void LCodeGen::DoMulI(LMulI* instr) {
   1538   Register left = ToRegister(instr->left());
   1539   LOperand* right = instr->right();
   1540 
   1541   if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
   1542     __ mov(ToRegister(instr->temp()), left);
   1543   }
   1544 
   1545   if (right->IsConstantOperand()) {
   1546     // Try strength reductions on the multiplication.
   1547     // All replacement instructions are at most as long as the imul
   1548     // and have better latency.
   1549     int constant = ToInteger32(LConstantOperand::cast(right));
   1550     if (constant == -1) {
   1551       __ neg(left);
   1552     } else if (constant == 0) {
   1553       __ xor_(left, Operand(left));
   1554     } else if (constant == 2) {
   1555       __ add(left, Operand(left));
   1556     } else if (!instr->hydrogen()->CheckFlag(HValue::kCanOverflow)) {
   1557       // If we know that the multiplication can't overflow, it's safe to
   1558       // use instructions that don't set the overflow flag for the
   1559       // multiplication.
   1560       switch (constant) {
   1561         case 1:
   1562           // Do nothing.
   1563           break;
   1564         case 3:
   1565           __ lea(left, Operand(left, left, times_2, 0));
   1566           break;
   1567         case 4:
   1568           __ shl(left, 2);
   1569           break;
   1570         case 5:
   1571           __ lea(left, Operand(left, left, times_4, 0));
   1572           break;
   1573         case 8:
   1574           __ shl(left, 3);
   1575           break;
   1576         case 9:
   1577           __ lea(left, Operand(left, left, times_8, 0));
   1578           break;
   1579         case 16:
   1580           __ shl(left, 4);
   1581           break;
   1582         default:
   1583           __ imul(left, left, constant);
   1584           break;
   1585       }
   1586     } else {
   1587       __ imul(left, left, constant);
   1588     }
   1589   } else {
   1590     if (instr->hydrogen()->representation().IsSmi()) {
   1591       __ SmiUntag(left);
   1592     }
   1593     __ imul(left, ToOperand(right));
   1594   }
   1595 
   1596   if (instr->hydrogen()->CheckFlag(HValue::kCanOverflow)) {
   1597     DeoptimizeIf(overflow, instr, DeoptimizeReason::kOverflow);
   1598   }
   1599 
   1600   if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
   1601     // Bail out if the result is supposed to be negative zero.
   1602     Label done;
   1603     __ test(left, Operand(left));
   1604     __ j(not_zero, &done);
   1605     if (right->IsConstantOperand()) {
   1606       if (ToInteger32(LConstantOperand::cast(right)) < 0) {
   1607         DeoptimizeIf(no_condition, instr, DeoptimizeReason::kMinusZero);
   1608       } else if (ToInteger32(LConstantOperand::cast(right)) == 0) {
   1609         __ cmp(ToRegister(instr->temp()), Immediate(0));
   1610         DeoptimizeIf(less, instr, DeoptimizeReason::kMinusZero);
   1611       }
   1612     } else {
   1613       // Test the non-zero operand for negative sign.
   1614       __ or_(ToRegister(instr->temp()), ToOperand(right));
   1615       DeoptimizeIf(sign, instr, DeoptimizeReason::kMinusZero);
   1616     }
   1617     __ bind(&done);
   1618   }
   1619 }
   1620 
   1621 
   1622 void LCodeGen::DoBitI(LBitI* instr) {
   1623   LOperand* left = instr->left();
   1624   LOperand* right = instr->right();
   1625   DCHECK(left->Equals(instr->result()));
   1626   DCHECK(left->IsRegister());
   1627 
   1628   if (right->IsConstantOperand()) {
   1629     int32_t right_operand =
   1630         ToRepresentation(LConstantOperand::cast(right),
   1631                          instr->hydrogen()->representation());
   1632     switch (instr->op()) {
   1633       case Token::BIT_AND:
   1634         __ and_(ToRegister(left), right_operand);
   1635         break;
   1636       case Token::BIT_OR:
   1637         __ or_(ToRegister(left), right_operand);
   1638         break;
   1639       case Token::BIT_XOR:
   1640         if (right_operand == int32_t(~0)) {
   1641           __ not_(ToRegister(left));
   1642         } else {
   1643           __ xor_(ToRegister(left), right_operand);
   1644         }
   1645         break;
   1646       default:
   1647         UNREACHABLE();
   1648         break;
   1649     }
   1650   } else {
   1651     switch (instr->op()) {
   1652       case Token::BIT_AND:
   1653         __ and_(ToRegister(left), ToOperand(right));
   1654         break;
   1655       case Token::BIT_OR:
   1656         __ or_(ToRegister(left), ToOperand(right));
   1657         break;
   1658       case Token::BIT_XOR:
   1659         __ xor_(ToRegister(left), ToOperand(right));
   1660         break;
   1661       default:
   1662         UNREACHABLE();
   1663         break;
   1664     }
   1665   }
   1666 }
   1667 
   1668 
   1669 void LCodeGen::DoShiftI(LShiftI* instr) {
   1670   LOperand* left = instr->left();
   1671   LOperand* right = instr->right();
   1672   DCHECK(left->Equals(instr->result()));
   1673   DCHECK(left->IsRegister());
   1674   if (right->IsRegister()) {
   1675     DCHECK(ToRegister(right).is(ecx));
   1676 
   1677     switch (instr->op()) {
   1678       case Token::ROR:
   1679         __ ror_cl(ToRegister(left));
   1680         break;
   1681       case Token::SAR:
   1682         __ sar_cl(ToRegister(left));
   1683         break;
   1684       case Token::SHR:
   1685         __ shr_cl(ToRegister(left));
   1686         if (instr->can_deopt()) {
   1687           __ test(ToRegister(left), ToRegister(left));
   1688           DeoptimizeIf(sign, instr, DeoptimizeReason::kNegativeValue);
   1689         }
   1690         break;
   1691       case Token::SHL:
   1692         __ shl_cl(ToRegister(left));
   1693         break;
   1694       default:
   1695         UNREACHABLE();
   1696         break;
   1697     }
   1698   } else {
   1699     int value = ToInteger32(LConstantOperand::cast(right));
   1700     uint8_t shift_count = static_cast<uint8_t>(value & 0x1F);
   1701     switch (instr->op()) {
   1702       case Token::ROR:
   1703         if (shift_count == 0 && instr->can_deopt()) {
   1704           __ test(ToRegister(left), ToRegister(left));
   1705           DeoptimizeIf(sign, instr, DeoptimizeReason::kNegativeValue);
   1706         } else {
   1707           __ ror(ToRegister(left), shift_count);
   1708         }
   1709         break;
   1710       case Token::SAR:
   1711         if (shift_count != 0) {
   1712           __ sar(ToRegister(left), shift_count);
   1713         }
   1714         break;
   1715       case Token::SHR:
   1716         if (shift_count != 0) {
   1717           __ shr(ToRegister(left), shift_count);
   1718         } else if (instr->can_deopt()) {
   1719           __ test(ToRegister(left), ToRegister(left));
   1720           DeoptimizeIf(sign, instr, DeoptimizeReason::kNegativeValue);
   1721         }
   1722         break;
   1723       case Token::SHL:
   1724         if (shift_count != 0) {
   1725           if (instr->hydrogen_value()->representation().IsSmi() &&
   1726               instr->can_deopt()) {
   1727             if (shift_count != 1) {
   1728               __ shl(ToRegister(left), shift_count - 1);
   1729             }
   1730             __ SmiTag(ToRegister(left));
   1731             DeoptimizeIf(overflow, instr, DeoptimizeReason::kOverflow);
   1732           } else {
   1733             __ shl(ToRegister(left), shift_count);
   1734           }
   1735         }
   1736         break;
   1737       default:
   1738         UNREACHABLE();
   1739         break;
   1740     }
   1741   }
   1742 }
   1743 
   1744 
   1745 void LCodeGen::DoSubI(LSubI* instr) {
   1746   LOperand* left = instr->left();
   1747   LOperand* right = instr->right();
   1748   DCHECK(left->Equals(instr->result()));
   1749 
   1750   if (right->IsConstantOperand()) {
   1751     __ sub(ToOperand(left),
   1752            ToImmediate(right, instr->hydrogen()->representation()));
   1753   } else {
   1754     __ sub(ToRegister(left), ToOperand(right));
   1755   }
   1756   if (instr->hydrogen()->CheckFlag(HValue::kCanOverflow)) {
   1757     DeoptimizeIf(overflow, instr, DeoptimizeReason::kOverflow);
   1758   }
   1759 }
   1760 
   1761 
   1762 void LCodeGen::DoConstantI(LConstantI* instr) {
   1763   __ Move(ToRegister(instr->result()), Immediate(instr->value()));
   1764 }
   1765 
   1766 
   1767 void LCodeGen::DoConstantS(LConstantS* instr) {
   1768   __ Move(ToRegister(instr->result()), Immediate(instr->value()));
   1769 }
   1770 
   1771 
   1772 void LCodeGen::DoConstantD(LConstantD* instr) {
   1773   uint64_t const bits = instr->bits();
   1774   uint32_t const lower = static_cast<uint32_t>(bits);
   1775   uint32_t const upper = static_cast<uint32_t>(bits >> 32);
   1776   DCHECK(instr->result()->IsDoubleRegister());
   1777 
   1778   __ push(Immediate(upper));
   1779   __ push(Immediate(lower));
   1780   X87Register reg = ToX87Register(instr->result());
   1781   X87Mov(reg, Operand(esp, 0));
   1782   __ add(Operand(esp), Immediate(kDoubleSize));
   1783 }
   1784 
   1785 
   1786 void LCodeGen::DoConstantE(LConstantE* instr) {
   1787   __ lea(ToRegister(instr->result()), Operand::StaticVariable(instr->value()));
   1788 }
   1789 
   1790 
   1791 void LCodeGen::DoConstantT(LConstantT* instr) {
   1792   Register reg = ToRegister(instr->result());
   1793   Handle<Object> object = instr->value(isolate());
   1794   AllowDeferredHandleDereference smi_check;
   1795   __ LoadObject(reg, object);
   1796 }
   1797 
   1798 
   1799 Operand LCodeGen::BuildSeqStringOperand(Register string,
   1800                                         LOperand* index,
   1801                                         String::Encoding encoding) {
   1802   if (index->IsConstantOperand()) {
   1803     int offset = ToRepresentation(LConstantOperand::cast(index),
   1804                                   Representation::Integer32());
   1805     if (encoding == String::TWO_BYTE_ENCODING) {
   1806       offset *= kUC16Size;
   1807     }
   1808     STATIC_ASSERT(kCharSize == 1);
   1809     return FieldOperand(string, SeqString::kHeaderSize + offset);
   1810   }
   1811   return FieldOperand(
   1812       string, ToRegister(index),
   1813       encoding == String::ONE_BYTE_ENCODING ? times_1 : times_2,
   1814       SeqString::kHeaderSize);
   1815 }
   1816 
   1817 
   1818 void LCodeGen::DoSeqStringGetChar(LSeqStringGetChar* instr) {
   1819   String::Encoding encoding = instr->hydrogen()->encoding();
   1820   Register result = ToRegister(instr->result());
   1821   Register string = ToRegister(instr->string());
   1822 
   1823   if (FLAG_debug_code) {
   1824     __ push(string);
   1825     __ mov(string, FieldOperand(string, HeapObject::kMapOffset));
   1826     __ movzx_b(string, FieldOperand(string, Map::kInstanceTypeOffset));
   1827 
   1828     __ and_(string, Immediate(kStringRepresentationMask | kStringEncodingMask));
   1829     static const uint32_t one_byte_seq_type = kSeqStringTag | kOneByteStringTag;
   1830     static const uint32_t two_byte_seq_type = kSeqStringTag | kTwoByteStringTag;
   1831     __ cmp(string, Immediate(encoding == String::ONE_BYTE_ENCODING
   1832                              ? one_byte_seq_type : two_byte_seq_type));
   1833     __ Check(equal, kUnexpectedStringType);
   1834     __ pop(string);
   1835   }
   1836 
   1837   Operand operand = BuildSeqStringOperand(string, instr->index(), encoding);
   1838   if (encoding == String::ONE_BYTE_ENCODING) {
   1839     __ movzx_b(result, operand);
   1840   } else {
   1841     __ movzx_w(result, operand);
   1842   }
   1843 }
   1844 
   1845 
   1846 void LCodeGen::DoSeqStringSetChar(LSeqStringSetChar* instr) {
   1847   String::Encoding encoding = instr->hydrogen()->encoding();
   1848   Register string = ToRegister(instr->string());
   1849 
   1850   if (FLAG_debug_code) {
   1851     Register value = ToRegister(instr->value());
   1852     Register index = ToRegister(instr->index());
   1853     static const uint32_t one_byte_seq_type = kSeqStringTag | kOneByteStringTag;
   1854     static const uint32_t two_byte_seq_type = kSeqStringTag | kTwoByteStringTag;
   1855     int encoding_mask =
   1856         instr->hydrogen()->encoding() == String::ONE_BYTE_ENCODING
   1857         ? one_byte_seq_type : two_byte_seq_type;
   1858     __ EmitSeqStringSetCharCheck(string, index, value, encoding_mask);
   1859   }
   1860 
   1861   Operand operand = BuildSeqStringOperand(string, instr->index(), encoding);
   1862   if (instr->value()->IsConstantOperand()) {
   1863     int value = ToRepresentation(LConstantOperand::cast(instr->value()),
   1864                                  Representation::Integer32());
   1865     DCHECK_LE(0, value);
   1866     if (encoding == String::ONE_BYTE_ENCODING) {
   1867       DCHECK_LE(value, String::kMaxOneByteCharCode);
   1868       __ mov_b(operand, static_cast<int8_t>(value));
   1869     } else {
   1870       DCHECK_LE(value, String::kMaxUtf16CodeUnit);
   1871       __ mov_w(operand, static_cast<int16_t>(value));
   1872     }
   1873   } else {
   1874     Register value = ToRegister(instr->value());
   1875     if (encoding == String::ONE_BYTE_ENCODING) {
   1876       __ mov_b(operand, value);
   1877     } else {
   1878       __ mov_w(operand, value);
   1879     }
   1880   }
   1881 }
   1882 
   1883 
   1884 void LCodeGen::DoAddI(LAddI* instr) {
   1885   LOperand* left = instr->left();
   1886   LOperand* right = instr->right();
   1887 
   1888   if (LAddI::UseLea(instr->hydrogen()) && !left->Equals(instr->result())) {
   1889     if (right->IsConstantOperand()) {
   1890       int32_t offset = ToRepresentation(LConstantOperand::cast(right),
   1891                                         instr->hydrogen()->representation());
   1892       __ lea(ToRegister(instr->result()), MemOperand(ToRegister(left), offset));
   1893     } else {
   1894       Operand address(ToRegister(left), ToRegister(right), times_1, 0);
   1895       __ lea(ToRegister(instr->result()), address);
   1896     }
   1897   } else {
   1898     if (right->IsConstantOperand()) {
   1899       __ add(ToOperand(left),
   1900              ToImmediate(right, instr->hydrogen()->representation()));
   1901     } else {
   1902       __ add(ToRegister(left), ToOperand(right));
   1903     }
   1904     if (instr->hydrogen()->CheckFlag(HValue::kCanOverflow)) {
   1905       DeoptimizeIf(overflow, instr, DeoptimizeReason::kOverflow);
   1906     }
   1907   }
   1908 }
   1909 
   1910 
   1911 void LCodeGen::DoMathMinMax(LMathMinMax* instr) {
   1912   LOperand* left = instr->left();
   1913   LOperand* right = instr->right();
   1914   DCHECK(left->Equals(instr->result()));
   1915   HMathMinMax::Operation operation = instr->hydrogen()->operation();
   1916   if (instr->hydrogen()->representation().IsSmiOrInteger32()) {
   1917     Label return_left;
   1918     Condition condition = (operation == HMathMinMax::kMathMin)
   1919         ? less_equal
   1920         : greater_equal;
   1921     if (right->IsConstantOperand()) {
   1922       Operand left_op = ToOperand(left);
   1923       Immediate immediate = ToImmediate(LConstantOperand::cast(instr->right()),
   1924                                         instr->hydrogen()->representation());
   1925       __ cmp(left_op, immediate);
   1926       __ j(condition, &return_left, Label::kNear);
   1927       __ mov(left_op, immediate);
   1928     } else {
   1929       Register left_reg = ToRegister(left);
   1930       Operand right_op = ToOperand(right);
   1931       __ cmp(left_reg, right_op);
   1932       __ j(condition, &return_left, Label::kNear);
   1933       __ mov(left_reg, right_op);
   1934     }
   1935     __ bind(&return_left);
   1936   } else {
   1937     DCHECK(instr->hydrogen()->representation().IsDouble());
   1938     Label check_nan_left, check_zero, return_left, return_right;
   1939     Condition condition = (operation == HMathMinMax::kMathMin) ? below : above;
   1940     X87Register left_reg = ToX87Register(left);
   1941     X87Register right_reg = ToX87Register(right);
   1942 
   1943     X87PrepareBinaryOp(left_reg, right_reg, ToX87Register(instr->result()));
   1944     __ fld(1);
   1945     __ fld(1);
   1946     __ FCmp();
   1947     __ j(parity_even, &check_nan_left, Label::kNear);  // At least one NaN.
   1948     __ j(equal, &check_zero, Label::kNear);            // left == right.
   1949     __ j(condition, &return_left, Label::kNear);
   1950     __ jmp(&return_right, Label::kNear);
   1951 
   1952     __ bind(&check_zero);
   1953     __ fld(0);
   1954     __ fldz();
   1955     __ FCmp();
   1956     __ j(not_equal, &return_left, Label::kNear);  // left == right != 0.
   1957     // At this point, both left and right are either 0 or -0.
   1958     if (operation == HMathMinMax::kMathMin) {
   1959       // Push st0 and st1 to stack, then pop them to temp registers and OR them,
   1960       // load it to left.
   1961       Register scratch_reg = ToRegister(instr->temp());
   1962       __ fld(1);
   1963       __ fld(1);
   1964       __ sub(esp, Immediate(2 * kPointerSize));
   1965       __ fstp_s(MemOperand(esp, 0));
   1966       __ fstp_s(MemOperand(esp, kPointerSize));
   1967       __ pop(scratch_reg);
   1968       __ or_(MemOperand(esp, 0), scratch_reg);
   1969       X87Mov(left_reg, MemOperand(esp, 0), kX87FloatOperand);
   1970       __ pop(scratch_reg);  // restore esp
   1971     } else {
   1972       // Since we operate on +0 and/or -0, addsd and andsd have the same effect.
   1973       // Should put the result in stX0
   1974       __ fadd_i(1);
   1975     }
   1976     __ jmp(&return_left, Label::kNear);
   1977 
   1978     __ bind(&check_nan_left);
   1979     __ fld(0);
   1980     __ fld(0);
   1981     __ FCmp();                                      // NaN check.
   1982     __ j(parity_even, &return_left, Label::kNear);  // left == NaN.
   1983 
   1984     __ bind(&return_right);
   1985     X87Mov(left_reg, right_reg);
   1986 
   1987     __ bind(&return_left);
   1988   }
   1989 }
   1990 
   1991 
   1992 void LCodeGen::DoArithmeticD(LArithmeticD* instr) {
   1993   X87Register left = ToX87Register(instr->left());
   1994   X87Register right = ToX87Register(instr->right());
   1995   X87Register result = ToX87Register(instr->result());
   1996   if (instr->op() != Token::MOD) {
   1997     X87PrepareBinaryOp(left, right, result);
   1998   }
   1999   // Set the precision control to double-precision.
   2000   __ X87SetFPUCW(0x027F);
   2001   switch (instr->op()) {
   2002     case Token::ADD:
   2003       __ fadd_i(1);
   2004       break;
   2005     case Token::SUB:
   2006       __ fsub_i(1);
   2007       break;
   2008     case Token::MUL:
   2009       __ fmul_i(1);
   2010       break;
   2011     case Token::DIV:
   2012       __ fdiv_i(1);
   2013       break;
   2014     case Token::MOD: {
   2015       // Pass two doubles as arguments on the stack.
   2016       __ PrepareCallCFunction(4, eax);
   2017       X87Mov(Operand(esp, 1 * kDoubleSize), right);
   2018       X87Mov(Operand(esp, 0), left);
   2019       X87Free(right);
   2020       DCHECK(left.is(result));
   2021       X87PrepareToWrite(result);
   2022       __ CallCFunction(
   2023           ExternalReference::mod_two_doubles_operation(isolate()),
   2024           4);
   2025 
   2026       // Return value is in st(0) on ia32.
   2027       X87CommitWrite(result);
   2028       break;
   2029     }
   2030     default:
   2031       UNREACHABLE();
   2032       break;
   2033   }
   2034 
   2035   // Restore the default value of control word.
   2036   __ X87SetFPUCW(0x037F);
   2037 }
   2038 
   2039 
   2040 void LCodeGen::DoArithmeticT(LArithmeticT* instr) {
   2041   DCHECK(ToRegister(instr->context()).is(esi));
   2042   DCHECK(ToRegister(instr->left()).is(edx));
   2043   DCHECK(ToRegister(instr->right()).is(eax));
   2044   DCHECK(ToRegister(instr->result()).is(eax));
   2045 
   2046   Handle<Code> code = CodeFactory::BinaryOpIC(isolate(), instr->op()).code();
   2047   CallCode(code, RelocInfo::CODE_TARGET, instr);
   2048 }
   2049 
   2050 
   2051 template<class InstrType>
   2052 void LCodeGen::EmitBranch(InstrType instr, Condition cc) {
   2053   int left_block = instr->TrueDestination(chunk_);
   2054   int right_block = instr->FalseDestination(chunk_);
   2055 
   2056   int next_block = GetNextEmittedBlock();
   2057 
   2058   if (right_block == left_block || cc == no_condition) {
   2059     EmitGoto(left_block);
   2060   } else if (left_block == next_block) {
   2061     __ j(NegateCondition(cc), chunk_->GetAssemblyLabel(right_block));
   2062   } else if (right_block == next_block) {
   2063     __ j(cc, chunk_->GetAssemblyLabel(left_block));
   2064   } else {
   2065     __ j(cc, chunk_->GetAssemblyLabel(left_block));
   2066     __ jmp(chunk_->GetAssemblyLabel(right_block));
   2067   }
   2068 }
   2069 
   2070 
   2071 template <class InstrType>
   2072 void LCodeGen::EmitTrueBranch(InstrType instr, Condition cc) {
   2073   int true_block = instr->TrueDestination(chunk_);
   2074   if (cc == no_condition) {
   2075     __ jmp(chunk_->GetAssemblyLabel(true_block));
   2076   } else {
   2077     __ j(cc, chunk_->GetAssemblyLabel(true_block));
   2078   }
   2079 }
   2080 
   2081 
   2082 template<class InstrType>
   2083 void LCodeGen::EmitFalseBranch(InstrType instr, Condition cc) {
   2084   int false_block = instr->FalseDestination(chunk_);
   2085   if (cc == no_condition) {
   2086     __ jmp(chunk_->GetAssemblyLabel(false_block));
   2087   } else {
   2088     __ j(cc, chunk_->GetAssemblyLabel(false_block));
   2089   }
   2090 }
   2091 
   2092 
   2093 void LCodeGen::DoBranch(LBranch* instr) {
   2094   Representation r = instr->hydrogen()->value()->representation();
   2095   if (r.IsSmiOrInteger32()) {
   2096     Register reg = ToRegister(instr->value());
   2097     __ test(reg, Operand(reg));
   2098     EmitBranch(instr, not_zero);
   2099   } else if (r.IsDouble()) {
   2100     X87Register reg = ToX87Register(instr->value());
   2101     X87LoadForUsage(reg);
   2102     __ fldz();
   2103     __ FCmp();
   2104     EmitBranch(instr, not_zero);
   2105   } else {
   2106     DCHECK(r.IsTagged());
   2107     Register reg = ToRegister(instr->value());
   2108     HType type = instr->hydrogen()->value()->type();
   2109     if (type.IsBoolean()) {
   2110       DCHECK(!info()->IsStub());
   2111       __ cmp(reg, factory()->true_value());
   2112       EmitBranch(instr, equal);
   2113     } else if (type.IsSmi()) {
   2114       DCHECK(!info()->IsStub());
   2115       __ test(reg, Operand(reg));
   2116       EmitBranch(instr, not_equal);
   2117     } else if (type.IsJSArray()) {
   2118       DCHECK(!info()->IsStub());
   2119       EmitBranch(instr, no_condition);
   2120     } else if (type.IsHeapNumber()) {
   2121       UNREACHABLE();
   2122     } else if (type.IsString()) {
   2123       DCHECK(!info()->IsStub());
   2124       __ cmp(FieldOperand(reg, String::kLengthOffset), Immediate(0));
   2125       EmitBranch(instr, not_equal);
   2126     } else {
   2127       ToBooleanHints expected = instr->hydrogen()->expected_input_types();
   2128       if (expected == ToBooleanHint::kNone) expected = ToBooleanHint::kAny;
   2129 
   2130       if (expected & ToBooleanHint::kUndefined) {
   2131         // undefined -> false.
   2132         __ cmp(reg, factory()->undefined_value());
   2133         __ j(equal, instr->FalseLabel(chunk_));
   2134       }
   2135       if (expected & ToBooleanHint::kBoolean) {
   2136         // true -> true.
   2137         __ cmp(reg, factory()->true_value());
   2138         __ j(equal, instr->TrueLabel(chunk_));
   2139         // false -> false.
   2140         __ cmp(reg, factory()->false_value());
   2141         __ j(equal, instr->FalseLabel(chunk_));
   2142       }
   2143       if (expected & ToBooleanHint::kNull) {
   2144         // 'null' -> false.
   2145         __ cmp(reg, factory()->null_value());
   2146         __ j(equal, instr->FalseLabel(chunk_));
   2147       }
   2148 
   2149       if (expected & ToBooleanHint::kSmallInteger) {
   2150         // Smis: 0 -> false, all other -> true.
   2151         __ test(reg, Operand(reg));
   2152         __ j(equal, instr->FalseLabel(chunk_));
   2153         __ JumpIfSmi(reg, instr->TrueLabel(chunk_));
   2154       } else if (expected & ToBooleanHint::kNeedsMap) {
   2155         // If we need a map later and have a Smi -> deopt.
   2156         __ test(reg, Immediate(kSmiTagMask));
   2157         DeoptimizeIf(zero, instr, DeoptimizeReason::kSmi);
   2158       }
   2159 
   2160       Register map = no_reg;  // Keep the compiler happy.
   2161       if (expected & ToBooleanHint::kNeedsMap) {
   2162         map = ToRegister(instr->temp());
   2163         DCHECK(!map.is(reg));
   2164         __ mov(map, FieldOperand(reg, HeapObject::kMapOffset));
   2165 
   2166         if (expected & ToBooleanHint::kCanBeUndetectable) {
   2167           // Undetectable -> false.
   2168           __ test_b(FieldOperand(map, Map::kBitFieldOffset),
   2169                     Immediate(1 << Map::kIsUndetectable));
   2170           __ j(not_zero, instr->FalseLabel(chunk_));
   2171         }
   2172       }
   2173 
   2174       if (expected & ToBooleanHint::kReceiver) {
   2175         // spec object -> true.
   2176         __ CmpInstanceType(map, FIRST_JS_RECEIVER_TYPE);
   2177         __ j(above_equal, instr->TrueLabel(chunk_));
   2178       }
   2179 
   2180       if (expected & ToBooleanHint::kString) {
   2181         // String value -> false iff empty.
   2182         Label not_string;
   2183         __ CmpInstanceType(map, FIRST_NONSTRING_TYPE);
   2184         __ j(above_equal, &not_string, Label::kNear);
   2185         __ cmp(FieldOperand(reg, String::kLengthOffset), Immediate(0));
   2186         __ j(not_zero, instr->TrueLabel(chunk_));
   2187         __ jmp(instr->FalseLabel(chunk_));
   2188         __ bind(&not_string);
   2189       }
   2190 
   2191       if (expected & ToBooleanHint::kSymbol) {
   2192         // Symbol value -> true.
   2193         __ CmpInstanceType(map, SYMBOL_TYPE);
   2194         __ j(equal, instr->TrueLabel(chunk_));
   2195       }
   2196 
   2197       if (expected & ToBooleanHint::kSimdValue) {
   2198         // SIMD value -> true.
   2199         __ CmpInstanceType(map, SIMD128_VALUE_TYPE);
   2200         __ j(equal, instr->TrueLabel(chunk_));
   2201       }
   2202 
   2203       if (expected & ToBooleanHint::kHeapNumber) {
   2204         // heap number -> false iff +0, -0, or NaN.
   2205         Label not_heap_number;
   2206         __ cmp(FieldOperand(reg, HeapObject::kMapOffset),
   2207                factory()->heap_number_map());
   2208         __ j(not_equal, &not_heap_number, Label::kNear);
   2209         __ fldz();
   2210         __ fld_d(FieldOperand(reg, HeapNumber::kValueOffset));
   2211         __ FCmp();
   2212         __ j(zero, instr->FalseLabel(chunk_));
   2213         __ jmp(instr->TrueLabel(chunk_));
   2214         __ bind(&not_heap_number);
   2215       }
   2216 
   2217       if (expected != ToBooleanHint::kAny) {
   2218         // We've seen something for the first time -> deopt.
   2219         // This can only happen if we are not generic already.
   2220         DeoptimizeIf(no_condition, instr, DeoptimizeReason::kUnexpectedObject);
   2221       }
   2222     }
   2223   }
   2224 }
   2225 
   2226 
   2227 void LCodeGen::EmitGoto(int block) {
   2228   if (!IsNextEmittedBlock(block)) {
   2229     __ jmp(chunk_->GetAssemblyLabel(LookupDestination(block)));
   2230   }
   2231 }
   2232 
   2233 
   2234 void LCodeGen::DoClobberDoubles(LClobberDoubles* instr) {
   2235 }
   2236 
   2237 
   2238 void LCodeGen::DoGoto(LGoto* instr) {
   2239   EmitGoto(instr->block_id());
   2240 }
   2241 
   2242 
   2243 Condition LCodeGen::TokenToCondition(Token::Value op, bool is_unsigned) {
   2244   Condition cond = no_condition;
   2245   switch (op) {
   2246     case Token::EQ:
   2247     case Token::EQ_STRICT:
   2248       cond = equal;
   2249       break;
   2250     case Token::NE:
   2251     case Token::NE_STRICT:
   2252       cond = not_equal;
   2253       break;
   2254     case Token::LT:
   2255       cond = is_unsigned ? below : less;
   2256       break;
   2257     case Token::GT:
   2258       cond = is_unsigned ? above : greater;
   2259       break;
   2260     case Token::LTE:
   2261       cond = is_unsigned ? below_equal : less_equal;
   2262       break;
   2263     case Token::GTE:
   2264       cond = is_unsigned ? above_equal : greater_equal;
   2265       break;
   2266     case Token::IN:
   2267     case Token::INSTANCEOF:
   2268     default:
   2269       UNREACHABLE();
   2270   }
   2271   return cond;
   2272 }
   2273 
   2274 
   2275 void LCodeGen::DoCompareNumericAndBranch(LCompareNumericAndBranch* instr) {
   2276   LOperand* left = instr->left();
   2277   LOperand* right = instr->right();
   2278   bool is_unsigned =
   2279       instr->is_double() ||
   2280       instr->hydrogen()->left()->CheckFlag(HInstruction::kUint32) ||
   2281       instr->hydrogen()->right()->CheckFlag(HInstruction::kUint32);
   2282   Condition cc = TokenToCondition(instr->op(), is_unsigned);
   2283 
   2284   if (left->IsConstantOperand() && right->IsConstantOperand()) {
   2285     // We can statically evaluate the comparison.
   2286     double left_val = ToDouble(LConstantOperand::cast(left));
   2287     double right_val = ToDouble(LConstantOperand::cast(right));
   2288     int next_block = Token::EvalComparison(instr->op(), left_val, right_val)
   2289                          ? instr->TrueDestination(chunk_)
   2290                          : instr->FalseDestination(chunk_);
   2291     EmitGoto(next_block);
   2292   } else {
   2293     if (instr->is_double()) {
   2294       X87LoadForUsage(ToX87Register(right), ToX87Register(left));
   2295       __ FCmp();
   2296       // Don't base result on EFLAGS when a NaN is involved. Instead
   2297       // jump to the false block.
   2298       __ j(parity_even, instr->FalseLabel(chunk_));
   2299     } else {
   2300       if (right->IsConstantOperand()) {
   2301         __ cmp(ToOperand(left),
   2302                ToImmediate(right, instr->hydrogen()->representation()));
   2303       } else if (left->IsConstantOperand()) {
   2304         __ cmp(ToOperand(right),
   2305                ToImmediate(left, instr->hydrogen()->representation()));
   2306         // We commuted the operands, so commute the condition.
   2307         cc = CommuteCondition(cc);
   2308       } else {
   2309         __ cmp(ToRegister(left), ToOperand(right));
   2310       }
   2311     }
   2312     EmitBranch(instr, cc);
   2313   }
   2314 }
   2315 
   2316 
   2317 void LCodeGen::DoCmpObjectEqAndBranch(LCmpObjectEqAndBranch* instr) {
   2318   Register left = ToRegister(instr->left());
   2319 
   2320   if (instr->right()->IsConstantOperand()) {
   2321     Handle<Object> right = ToHandle(LConstantOperand::cast(instr->right()));
   2322     __ CmpObject(left, right);
   2323   } else {
   2324     Operand right = ToOperand(instr->right());
   2325     __ cmp(left, right);
   2326   }
   2327   EmitBranch(instr, equal);
   2328 }
   2329 
   2330 
   2331 void LCodeGen::DoCmpHoleAndBranch(LCmpHoleAndBranch* instr) {
   2332   if (instr->hydrogen()->representation().IsTagged()) {
   2333     Register input_reg = ToRegister(instr->object());
   2334     __ cmp(input_reg, factory()->the_hole_value());
   2335     EmitBranch(instr, equal);
   2336     return;
   2337   }
   2338 
   2339   // Put the value to the top of stack
   2340   X87Register src = ToX87Register(instr->object());
   2341   X87LoadForUsage(src);
   2342   __ fld(0);
   2343   __ fld(0);
   2344   __ FCmp();
   2345   Label ok;
   2346   __ j(parity_even, &ok, Label::kNear);
   2347   __ fstp(0);
   2348   EmitFalseBranch(instr, no_condition);
   2349   __ bind(&ok);
   2350 
   2351 
   2352   __ sub(esp, Immediate(kDoubleSize));
   2353   __ fstp_d(MemOperand(esp, 0));
   2354 
   2355   __ add(esp, Immediate(kDoubleSize));
   2356   int offset = sizeof(kHoleNanUpper32);
   2357   __ cmp(MemOperand(esp, -offset), Immediate(kHoleNanUpper32));
   2358   EmitBranch(instr, equal);
   2359 }
   2360 
   2361 
   2362 Condition LCodeGen::EmitIsString(Register input,
   2363                                  Register temp1,
   2364                                  Label* is_not_string,
   2365                                  SmiCheck check_needed = INLINE_SMI_CHECK) {
   2366   if (check_needed == INLINE_SMI_CHECK) {
   2367     __ JumpIfSmi(input, is_not_string);
   2368   }
   2369 
   2370   Condition cond = masm_->IsObjectStringType(input, temp1, temp1);
   2371 
   2372   return cond;
   2373 }
   2374 
   2375 
   2376 void LCodeGen::DoIsStringAndBranch(LIsStringAndBranch* instr) {
   2377   Register reg = ToRegister(instr->value());
   2378   Register temp = ToRegister(instr->temp());
   2379 
   2380   SmiCheck check_needed =
   2381       instr->hydrogen()->value()->type().IsHeapObject()
   2382           ? OMIT_SMI_CHECK : INLINE_SMI_CHECK;
   2383 
   2384   Condition true_cond = EmitIsString(
   2385       reg, temp, instr->FalseLabel(chunk_), check_needed);
   2386 
   2387   EmitBranch(instr, true_cond);
   2388 }
   2389 
   2390 
   2391 void LCodeGen::DoIsSmiAndBranch(LIsSmiAndBranch* instr) {
   2392   Operand input = ToOperand(instr->value());
   2393 
   2394   __ test(input, Immediate(kSmiTagMask));
   2395   EmitBranch(instr, zero);
   2396 }
   2397 
   2398 
   2399 void LCodeGen::DoIsUndetectableAndBranch(LIsUndetectableAndBranch* instr) {
   2400   Register input = ToRegister(instr->value());
   2401   Register temp = ToRegister(instr->temp());
   2402 
   2403   if (!instr->hydrogen()->value()->type().IsHeapObject()) {
   2404     STATIC_ASSERT(kSmiTag == 0);
   2405     __ JumpIfSmi(input, instr->FalseLabel(chunk_));
   2406   }
   2407   __ mov(temp, FieldOperand(input, HeapObject::kMapOffset));
   2408   __ test_b(FieldOperand(temp, Map::kBitFieldOffset),
   2409             Immediate(1 << Map::kIsUndetectable));
   2410   EmitBranch(instr, not_zero);
   2411 }
   2412 
   2413 
   2414 static Condition ComputeCompareCondition(Token::Value op) {
   2415   switch (op) {
   2416     case Token::EQ_STRICT:
   2417     case Token::EQ:
   2418       return equal;
   2419     case Token::LT:
   2420       return less;
   2421     case Token::GT:
   2422       return greater;
   2423     case Token::LTE:
   2424       return less_equal;
   2425     case Token::GTE:
   2426       return greater_equal;
   2427     default:
   2428       UNREACHABLE();
   2429       return no_condition;
   2430   }
   2431 }
   2432 
   2433 
   2434 void LCodeGen::DoStringCompareAndBranch(LStringCompareAndBranch* instr) {
   2435   DCHECK(ToRegister(instr->context()).is(esi));
   2436   DCHECK(ToRegister(instr->left()).is(edx));
   2437   DCHECK(ToRegister(instr->right()).is(eax));
   2438 
   2439   Handle<Code> code = CodeFactory::StringCompare(isolate(), instr->op()).code();
   2440   CallCode(code, RelocInfo::CODE_TARGET, instr);
   2441   __ CompareRoot(eax, Heap::kTrueValueRootIndex);
   2442   EmitBranch(instr, equal);
   2443 }
   2444 
   2445 
   2446 static InstanceType TestType(HHasInstanceTypeAndBranch* instr) {
   2447   InstanceType from = instr->from();
   2448   InstanceType to = instr->to();
   2449   if (from == FIRST_TYPE) return to;
   2450   DCHECK(from == to || to == LAST_TYPE);
   2451   return from;
   2452 }
   2453 
   2454 
   2455 static Condition BranchCondition(HHasInstanceTypeAndBranch* instr) {
   2456   InstanceType from = instr->from();
   2457   InstanceType to = instr->to();
   2458   if (from == to) return equal;
   2459   if (to == LAST_TYPE) return above_equal;
   2460   if (from == FIRST_TYPE) return below_equal;
   2461   UNREACHABLE();
   2462   return equal;
   2463 }
   2464 
   2465 
   2466 void LCodeGen::DoHasInstanceTypeAndBranch(LHasInstanceTypeAndBranch* instr) {
   2467   Register input = ToRegister(instr->value());
   2468   Register temp = ToRegister(instr->temp());
   2469 
   2470   if (!instr->hydrogen()->value()->type().IsHeapObject()) {
   2471     __ JumpIfSmi(input, instr->FalseLabel(chunk_));
   2472   }
   2473 
   2474   __ CmpObjectType(input, TestType(instr->hydrogen()), temp);
   2475   EmitBranch(instr, BranchCondition(instr->hydrogen()));
   2476 }
   2477 
   2478 // Branches to a label or falls through with the answer in the z flag.  Trashes
   2479 // the temp registers, but not the input.
   2480 void LCodeGen::EmitClassOfTest(Label* is_true,
   2481                                Label* is_false,
   2482                                Handle<String>class_name,
   2483                                Register input,
   2484                                Register temp,
   2485                                Register temp2) {
   2486   DCHECK(!input.is(temp));
   2487   DCHECK(!input.is(temp2));
   2488   DCHECK(!temp.is(temp2));
   2489   __ JumpIfSmi(input, is_false);
   2490 
   2491   __ CmpObjectType(input, FIRST_FUNCTION_TYPE, temp);
   2492   STATIC_ASSERT(LAST_FUNCTION_TYPE == LAST_TYPE);
   2493   if (String::Equals(isolate()->factory()->Function_string(), class_name)) {
   2494     __ j(above_equal, is_true);
   2495   } else {
   2496     __ j(above_equal, is_false);
   2497   }
   2498 
   2499   // Now we are in the FIRST-LAST_NONCALLABLE_SPEC_OBJECT_TYPE range.
   2500   // Check if the constructor in the map is a function.
   2501   __ GetMapConstructor(temp, temp, temp2);
   2502   // Objects with a non-function constructor have class 'Object'.
   2503   __ CmpInstanceType(temp2, JS_FUNCTION_TYPE);
   2504   if (String::Equals(class_name, isolate()->factory()->Object_string())) {
   2505     __ j(not_equal, is_true);
   2506   } else {
   2507     __ j(not_equal, is_false);
   2508   }
   2509 
   2510   // temp now contains the constructor function. Grab the
   2511   // instance class name from there.
   2512   __ mov(temp, FieldOperand(temp, JSFunction::kSharedFunctionInfoOffset));
   2513   __ mov(temp, FieldOperand(temp,
   2514                             SharedFunctionInfo::kInstanceClassNameOffset));
   2515   // The class name we are testing against is internalized since it's a literal.
   2516   // The name in the constructor is internalized because of the way the context
   2517   // is booted.  This routine isn't expected to work for random API-created
   2518   // classes and it doesn't have to because you can't access it with natives
   2519   // syntax.  Since both sides are internalized it is sufficient to use an
   2520   // identity comparison.
   2521   __ cmp(temp, class_name);
   2522   // End with the answer in the z flag.
   2523 }
   2524 
   2525 
   2526 void LCodeGen::DoClassOfTestAndBranch(LClassOfTestAndBranch* instr) {
   2527   Register input = ToRegister(instr->value());
   2528   Register temp = ToRegister(instr->temp());
   2529   Register temp2 = ToRegister(instr->temp2());
   2530 
   2531   Handle<String> class_name = instr->hydrogen()->class_name();
   2532 
   2533   EmitClassOfTest(instr->TrueLabel(chunk_), instr->FalseLabel(chunk_),
   2534       class_name, input, temp, temp2);
   2535 
   2536   EmitBranch(instr, equal);
   2537 }
   2538 
   2539 
   2540 void LCodeGen::DoCmpMapAndBranch(LCmpMapAndBranch* instr) {
   2541   Register reg = ToRegister(instr->value());
   2542   __ cmp(FieldOperand(reg, HeapObject::kMapOffset), instr->map());
   2543   EmitBranch(instr, equal);
   2544 }
   2545 
   2546 
   2547 void LCodeGen::DoHasInPrototypeChainAndBranch(
   2548     LHasInPrototypeChainAndBranch* instr) {
   2549   Register const object = ToRegister(instr->object());
   2550   Register const object_map = ToRegister(instr->scratch());
   2551   Register const object_prototype = object_map;
   2552   Register const prototype = ToRegister(instr->prototype());
   2553 
   2554   // The {object} must be a spec object.  It's sufficient to know that {object}
   2555   // is not a smi, since all other non-spec objects have {null} prototypes and
   2556   // will be ruled out below.
   2557   if (instr->hydrogen()->ObjectNeedsSmiCheck()) {
   2558     __ test(object, Immediate(kSmiTagMask));
   2559     EmitFalseBranch(instr, zero);
   2560   }
   2561 
   2562   // Loop through the {object}s prototype chain looking for the {prototype}.
   2563   __ mov(object_map, FieldOperand(object, HeapObject::kMapOffset));
   2564   Label loop;
   2565   __ bind(&loop);
   2566 
   2567   // Deoptimize if the object needs to be access checked.
   2568   __ test_b(FieldOperand(object_map, Map::kBitFieldOffset),
   2569             Immediate(1 << Map::kIsAccessCheckNeeded));
   2570   DeoptimizeIf(not_zero, instr, DeoptimizeReason::kAccessCheck);
   2571   // Deoptimize for proxies.
   2572   __ CmpInstanceType(object_map, JS_PROXY_TYPE);
   2573   DeoptimizeIf(equal, instr, DeoptimizeReason::kProxy);
   2574 
   2575   __ mov(object_prototype, FieldOperand(object_map, Map::kPrototypeOffset));
   2576   __ cmp(object_prototype, factory()->null_value());
   2577   EmitFalseBranch(instr, equal);
   2578   __ cmp(object_prototype, prototype);
   2579   EmitTrueBranch(instr, equal);
   2580   __ mov(object_map, FieldOperand(object_prototype, HeapObject::kMapOffset));
   2581   __ jmp(&loop);
   2582 }
   2583 
   2584 
   2585 void LCodeGen::DoCmpT(LCmpT* instr) {
   2586   Token::Value op = instr->op();
   2587 
   2588   Handle<Code> ic = CodeFactory::CompareIC(isolate(), op).code();
   2589   CallCode(ic, RelocInfo::CODE_TARGET, instr);
   2590 
   2591   Condition condition = ComputeCompareCondition(op);
   2592   Label true_value, done;
   2593   __ test(eax, Operand(eax));
   2594   __ j(condition, &true_value, Label::kNear);
   2595   __ mov(ToRegister(instr->result()), factory()->false_value());
   2596   __ jmp(&done, Label::kNear);
   2597   __ bind(&true_value);
   2598   __ mov(ToRegister(instr->result()), factory()->true_value());
   2599   __ bind(&done);
   2600 }
   2601 
   2602 void LCodeGen::EmitReturn(LReturn* instr) {
   2603   int extra_value_count = 1;
   2604 
   2605   if (instr->has_constant_parameter_count()) {
   2606     int parameter_count = ToInteger32(instr->constant_parameter_count());
   2607     __ Ret((parameter_count + extra_value_count) * kPointerSize, ecx);
   2608   } else {
   2609     DCHECK(info()->IsStub());  // Functions would need to drop one more value.
   2610     Register reg = ToRegister(instr->parameter_count());
   2611     // The argument count parameter is a smi
   2612     __ SmiUntag(reg);
   2613     Register return_addr_reg = reg.is(ecx) ? ebx : ecx;
   2614 
   2615     // emit code to restore stack based on instr->parameter_count()
   2616     __ pop(return_addr_reg);  // save return address
   2617     __ shl(reg, kPointerSizeLog2);
   2618     __ add(esp, reg);
   2619     __ jmp(return_addr_reg);
   2620   }
   2621 }
   2622 
   2623 
   2624 void LCodeGen::DoReturn(LReturn* instr) {
   2625   if (FLAG_trace && info()->IsOptimizing()) {
   2626     // Preserve the return value on the stack and rely on the runtime call
   2627     // to return the value in the same register.  We're leaving the code
   2628     // managed by the register allocator and tearing down the frame, it's
   2629     // safe to write to the context register.
   2630     __ push(eax);
   2631     __ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
   2632     __ CallRuntime(Runtime::kTraceExit);
   2633   }
   2634   if (NeedsEagerFrame()) {
   2635     __ mov(esp, ebp);
   2636     __ pop(ebp);
   2637   }
   2638 
   2639   EmitReturn(instr);
   2640 }
   2641 
   2642 
   2643 void LCodeGen::DoLoadContextSlot(LLoadContextSlot* instr) {
   2644   Register context = ToRegister(instr->context());
   2645   Register result = ToRegister(instr->result());
   2646   __ mov(result, ContextOperand(context, instr->slot_index()));
   2647 
   2648   if (instr->hydrogen()->RequiresHoleCheck()) {
   2649     __ cmp(result, factory()->the_hole_value());
   2650     if (instr->hydrogen()->DeoptimizesOnHole()) {
   2651       DeoptimizeIf(equal, instr, DeoptimizeReason::kHole);
   2652     } else {
   2653       Label is_not_hole;
   2654       __ j(not_equal, &is_not_hole, Label::kNear);
   2655       __ mov(result, factory()->undefined_value());
   2656       __ bind(&is_not_hole);
   2657     }
   2658   }
   2659 }
   2660 
   2661 
   2662 void LCodeGen::DoStoreContextSlot(LStoreContextSlot* instr) {
   2663   Register context = ToRegister(instr->context());
   2664   Register value = ToRegister(instr->value());
   2665 
   2666   Label skip_assignment;
   2667 
   2668   Operand target = ContextOperand(context, instr->slot_index());
   2669   if (instr->hydrogen()->RequiresHoleCheck()) {
   2670     __ cmp(target, factory()->the_hole_value());
   2671     if (instr->hydrogen()->DeoptimizesOnHole()) {
   2672       DeoptimizeIf(equal, instr, DeoptimizeReason::kHole);
   2673     } else {
   2674       __ j(not_equal, &skip_assignment, Label::kNear);
   2675     }
   2676   }
   2677 
   2678   __ mov(target, value);
   2679   if (instr->hydrogen()->NeedsWriteBarrier()) {
   2680     SmiCheck check_needed =
   2681         instr->hydrogen()->value()->type().IsHeapObject()
   2682             ? OMIT_SMI_CHECK : INLINE_SMI_CHECK;
   2683     Register temp = ToRegister(instr->temp());
   2684     int offset = Context::SlotOffset(instr->slot_index());
   2685     __ RecordWriteContextSlot(context, offset, value, temp, kSaveFPRegs,
   2686                               EMIT_REMEMBERED_SET, check_needed);
   2687   }
   2688 
   2689   __ bind(&skip_assignment);
   2690 }
   2691 
   2692 
   2693 void LCodeGen::DoLoadNamedField(LLoadNamedField* instr) {
   2694   HObjectAccess access = instr->hydrogen()->access();
   2695   int offset = access.offset();
   2696 
   2697   if (access.IsExternalMemory()) {
   2698     Register result = ToRegister(instr->result());
   2699     MemOperand operand = instr->object()->IsConstantOperand()
   2700         ? MemOperand::StaticVariable(ToExternalReference(
   2701                 LConstantOperand::cast(instr->object())))
   2702         : MemOperand(ToRegister(instr->object()), offset);
   2703     __ Load(result, operand, access.representation());
   2704     return;
   2705   }
   2706 
   2707   Register object = ToRegister(instr->object());
   2708   if (instr->hydrogen()->representation().IsDouble()) {
   2709     X87Mov(ToX87Register(instr->result()), FieldOperand(object, offset));
   2710     return;
   2711   }
   2712 
   2713   Register result = ToRegister(instr->result());
   2714   if (!access.IsInobject()) {
   2715     __ mov(result, FieldOperand(object, JSObject::kPropertiesOffset));
   2716     object = result;
   2717   }
   2718   __ Load(result, FieldOperand(object, offset), access.representation());
   2719 }
   2720 
   2721 
   2722 void LCodeGen::EmitPushTaggedOperand(LOperand* operand) {
   2723   DCHECK(!operand->IsDoubleRegister());
   2724   if (operand->IsConstantOperand()) {
   2725     Handle<Object> object = ToHandle(LConstantOperand::cast(operand));
   2726     AllowDeferredHandleDereference smi_check;
   2727     if (object->IsSmi()) {
   2728       __ Push(Handle<Smi>::cast(object));
   2729     } else {
   2730       __ PushHeapObject(Handle<HeapObject>::cast(object));
   2731     }
   2732   } else if (operand->IsRegister()) {
   2733     __ push(ToRegister(operand));
   2734   } else {
   2735     __ push(ToOperand(operand));
   2736   }
   2737 }
   2738 
   2739 
   2740 void LCodeGen::DoLoadFunctionPrototype(LLoadFunctionPrototype* instr) {
   2741   Register function = ToRegister(instr->function());
   2742   Register temp = ToRegister(instr->temp());
   2743   Register result = ToRegister(instr->result());
   2744 
   2745   // Get the prototype or initial map from the function.
   2746   __ mov(result,
   2747          FieldOperand(function, JSFunction::kPrototypeOrInitialMapOffset));
   2748 
   2749   // Check that the function has a prototype or an initial map.
   2750   __ cmp(Operand(result), Immediate(factory()->the_hole_value()));
   2751   DeoptimizeIf(equal, instr, DeoptimizeReason::kHole);
   2752 
   2753   // If the function does not have an initial map, we're done.
   2754   Label done;
   2755   __ CmpObjectType(result, MAP_TYPE, temp);
   2756   __ j(not_equal, &done, Label::kNear);
   2757 
   2758   // Get the prototype from the initial map.
   2759   __ mov(result, FieldOperand(result, Map::kPrototypeOffset));
   2760 
   2761   // All done.
   2762   __ bind(&done);
   2763 }
   2764 
   2765 
   2766 void LCodeGen::DoLoadRoot(LLoadRoot* instr) {
   2767   Register result = ToRegister(instr->result());
   2768   __ LoadRoot(result, instr->index());
   2769 }
   2770 
   2771 
   2772 void LCodeGen::DoAccessArgumentsAt(LAccessArgumentsAt* instr) {
   2773   Register arguments = ToRegister(instr->arguments());
   2774   Register result = ToRegister(instr->result());
   2775   if (instr->length()->IsConstantOperand() &&
   2776       instr->index()->IsConstantOperand()) {
   2777     int const_index = ToInteger32(LConstantOperand::cast(instr->index()));
   2778     int const_length = ToInteger32(LConstantOperand::cast(instr->length()));
   2779     int index = (const_length - const_index) + 1;
   2780     __ mov(result, Operand(arguments, index * kPointerSize));
   2781   } else {
   2782     Register length = ToRegister(instr->length());
   2783     Operand index = ToOperand(instr->index());
   2784     // There are two words between the frame pointer and the last argument.
   2785     // Subtracting from length accounts for one of them add one more.
   2786     __ sub(length, index);
   2787     __ mov(result, Operand(arguments, length, times_4, kPointerSize));
   2788   }
   2789 }
   2790 
   2791 
   2792 void LCodeGen::DoLoadKeyedExternalArray(LLoadKeyed* instr) {
   2793   ElementsKind elements_kind = instr->elements_kind();
   2794   LOperand* key = instr->key();
   2795   if (!key->IsConstantOperand() &&
   2796       ExternalArrayOpRequiresTemp(instr->hydrogen()->key()->representation(),
   2797                                   elements_kind)) {
   2798     __ SmiUntag(ToRegister(key));
   2799   }
   2800   Operand operand(BuildFastArrayOperand(
   2801       instr->elements(),
   2802       key,
   2803       instr->hydrogen()->key()->representation(),
   2804       elements_kind,
   2805       instr->base_offset()));
   2806   if (elements_kind == FLOAT32_ELEMENTS) {
   2807     X87Mov(ToX87Register(instr->result()), operand, kX87FloatOperand);
   2808   } else if (elements_kind == FLOAT64_ELEMENTS) {
   2809     X87Mov(ToX87Register(instr->result()), operand);
   2810   } else {
   2811     Register result(ToRegister(instr->result()));
   2812     switch (elements_kind) {
   2813       case INT8_ELEMENTS:
   2814         __ movsx_b(result, operand);
   2815         break;
   2816       case UINT8_ELEMENTS:
   2817       case UINT8_CLAMPED_ELEMENTS:
   2818         __ movzx_b(result, operand);
   2819         break;
   2820       case INT16_ELEMENTS:
   2821         __ movsx_w(result, operand);
   2822         break;
   2823       case UINT16_ELEMENTS:
   2824         __ movzx_w(result, operand);
   2825         break;
   2826       case INT32_ELEMENTS:
   2827         __ mov(result, operand);
   2828         break;
   2829       case UINT32_ELEMENTS:
   2830         __ mov(result, operand);
   2831         if (!instr->hydrogen()->CheckFlag(HInstruction::kUint32)) {
   2832           __ test(result, Operand(result));
   2833           DeoptimizeIf(negative, instr, DeoptimizeReason::kNegativeValue);
   2834         }
   2835         break;
   2836       case FLOAT32_ELEMENTS:
   2837       case FLOAT64_ELEMENTS:
   2838       case FAST_SMI_ELEMENTS:
   2839       case FAST_ELEMENTS:
   2840       case FAST_DOUBLE_ELEMENTS:
   2841       case FAST_HOLEY_SMI_ELEMENTS:
   2842       case FAST_HOLEY_ELEMENTS:
   2843       case FAST_HOLEY_DOUBLE_ELEMENTS:
   2844       case DICTIONARY_ELEMENTS:
   2845       case FAST_SLOPPY_ARGUMENTS_ELEMENTS:
   2846       case SLOW_SLOPPY_ARGUMENTS_ELEMENTS:
   2847       case FAST_STRING_WRAPPER_ELEMENTS:
   2848       case SLOW_STRING_WRAPPER_ELEMENTS:
   2849       case NO_ELEMENTS:
   2850         UNREACHABLE();
   2851         break;
   2852     }
   2853   }
   2854 }
   2855 
   2856 
   2857 void LCodeGen::DoLoadKeyedFixedDoubleArray(LLoadKeyed* instr) {
   2858   if (instr->hydrogen()->RequiresHoleCheck()) {
   2859     Operand hole_check_operand = BuildFastArrayOperand(
   2860         instr->elements(), instr->key(),
   2861         instr->hydrogen()->key()->representation(),
   2862         FAST_DOUBLE_ELEMENTS,
   2863         instr->base_offset() + sizeof(kHoleNanLower32));
   2864     __ cmp(hole_check_operand, Immediate(kHoleNanUpper32));
   2865     DeoptimizeIf(equal, instr, DeoptimizeReason::kHole);
   2866   }
   2867 
   2868   Operand double_load_operand = BuildFastArrayOperand(
   2869       instr->elements(),
   2870       instr->key(),
   2871       instr->hydrogen()->key()->representation(),
   2872       FAST_DOUBLE_ELEMENTS,
   2873       instr->base_offset());
   2874   X87Mov(ToX87Register(instr->result()), double_load_operand);
   2875 }
   2876 
   2877 
   2878 void LCodeGen::DoLoadKeyedFixedArray(LLoadKeyed* instr) {
   2879   Register result = ToRegister(instr->result());
   2880 
   2881   // Load the result.
   2882   __ mov(result,
   2883          BuildFastArrayOperand(instr->elements(), instr->key(),
   2884                                instr->hydrogen()->key()->representation(),
   2885                                FAST_ELEMENTS, instr->base_offset()));
   2886 
   2887   // Check for the hole value.
   2888   if (instr->hydrogen()->RequiresHoleCheck()) {
   2889     if (IsFastSmiElementsKind(instr->hydrogen()->elements_kind())) {
   2890       __ test(result, Immediate(kSmiTagMask));
   2891       DeoptimizeIf(not_equal, instr, DeoptimizeReason::kNotASmi);
   2892     } else {
   2893       __ cmp(result, factory()->the_hole_value());
   2894       DeoptimizeIf(equal, instr, DeoptimizeReason::kHole);
   2895     }
   2896   } else if (instr->hydrogen()->hole_mode() == CONVERT_HOLE_TO_UNDEFINED) {
   2897     DCHECK(instr->hydrogen()->elements_kind() == FAST_HOLEY_ELEMENTS);
   2898     Label done;
   2899     __ cmp(result, factory()->the_hole_value());
   2900     __ j(not_equal, &done);
   2901     if (info()->IsStub()) {
   2902       // A stub can safely convert the hole to undefined only if the array
   2903       // protector cell contains (Smi) Isolate::kProtectorValid.
   2904       // Otherwise it needs to bail out.
   2905       __ LoadRoot(result, Heap::kArrayProtectorRootIndex);
   2906       __ cmp(FieldOperand(result, PropertyCell::kValueOffset),
   2907              Immediate(Smi::FromInt(Isolate::kProtectorValid)));
   2908       DeoptimizeIf(not_equal, instr, DeoptimizeReason::kHole);
   2909     }
   2910     __ mov(result, isolate()->factory()->undefined_value());
   2911     __ bind(&done);
   2912   }
   2913 }
   2914 
   2915 
   2916 void LCodeGen::DoLoadKeyed(LLoadKeyed* instr) {
   2917   if (instr->is_fixed_typed_array()) {
   2918     DoLoadKeyedExternalArray(instr);
   2919   } else if (instr->hydrogen()->representation().IsDouble()) {
   2920     DoLoadKeyedFixedDoubleArray(instr);
   2921   } else {
   2922     DoLoadKeyedFixedArray(instr);
   2923   }
   2924 }
   2925 
   2926 
   2927 Operand LCodeGen::BuildFastArrayOperand(
   2928     LOperand* elements_pointer,
   2929     LOperand* key,
   2930     Representation key_representation,
   2931     ElementsKind elements_kind,
   2932     uint32_t base_offset) {
   2933   Register elements_pointer_reg = ToRegister(elements_pointer);
   2934   int element_shift_size = ElementsKindToShiftSize(elements_kind);
   2935   int shift_size = element_shift_size;
   2936   if (key->IsConstantOperand()) {
   2937     int constant_value = ToInteger32(LConstantOperand::cast(key));
   2938     if (constant_value & 0xF0000000) {
   2939       Abort(kArrayIndexConstantValueTooBig);
   2940     }
   2941     return Operand(elements_pointer_reg,
   2942                    ((constant_value) << shift_size)
   2943                        + base_offset);
   2944   } else {
   2945     // Take the tag bit into account while computing the shift size.
   2946     if (key_representation.IsSmi() && (shift_size >= 1)) {
   2947       shift_size -= kSmiTagSize;
   2948     }
   2949     ScaleFactor scale_factor = static_cast<ScaleFactor>(shift_size);
   2950     return Operand(elements_pointer_reg,
   2951                    ToRegister(key),
   2952                    scale_factor,
   2953                    base_offset);
   2954   }
   2955 }
   2956 
   2957 
   2958 void LCodeGen::DoArgumentsElements(LArgumentsElements* instr) {
   2959   Register result = ToRegister(instr->result());
   2960 
   2961   if (instr->hydrogen()->from_inlined()) {
   2962     __ lea(result, Operand(esp, -2 * kPointerSize));
   2963   } else if (instr->hydrogen()->arguments_adaptor()) {
   2964     // Check for arguments adapter frame.
   2965     Label done, adapted;
   2966     __ mov(result, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
   2967     __ mov(result,
   2968            Operand(result, CommonFrameConstants::kContextOrFrameTypeOffset));
   2969     __ cmp(Operand(result),
   2970            Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
   2971     __ j(equal, &adapted, Label::kNear);
   2972 
   2973     // No arguments adaptor frame.
   2974     __ mov(result, Operand(ebp));
   2975     __ jmp(&done, Label::kNear);
   2976 
   2977     // Arguments adaptor frame present.
   2978     __ bind(&adapted);
   2979     __ mov(result, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
   2980 
   2981     // Result is the frame pointer for the frame if not adapted and for the real
   2982     // frame below the adaptor frame if adapted.
   2983     __ bind(&done);
   2984   } else {
   2985     __ mov(result, Operand(ebp));
   2986   }
   2987 }
   2988 
   2989 
   2990 void LCodeGen::DoArgumentsLength(LArgumentsLength* instr) {
   2991   Operand elem = ToOperand(instr->elements());
   2992   Register result = ToRegister(instr->result());
   2993 
   2994   Label done;
   2995 
   2996   // If no arguments adaptor frame the number of arguments is fixed.
   2997   __ cmp(ebp, elem);
   2998   __ mov(result, Immediate(scope()->num_parameters()));
   2999   __ j(equal, &done, Label::kNear);
   3000 
   3001   // Arguments adaptor frame present. Get argument length from there.
   3002   __ mov(result, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
   3003   __ mov(result, Operand(result,
   3004                          ArgumentsAdaptorFrameConstants::kLengthOffset));
   3005   __ SmiUntag(result);
   3006 
   3007   // Argument length is in result register.
   3008   __ bind(&done);
   3009 }
   3010 
   3011 
   3012 void LCodeGen::DoWrapReceiver(LWrapReceiver* instr) {
   3013   Register receiver = ToRegister(instr->receiver());
   3014   Register function = ToRegister(instr->function());
   3015 
   3016   // If the receiver is null or undefined, we have to pass the global
   3017   // object as a receiver to normal functions. Values have to be
   3018   // passed unchanged to builtins and strict-mode functions.
   3019   Label receiver_ok, global_object;
   3020   Label::Distance dist = DeoptEveryNTimes() ? Label::kFar : Label::kNear;
   3021   Register scratch = ToRegister(instr->temp());
   3022 
   3023   if (!instr->hydrogen()->known_function()) {
   3024     // Do not transform the receiver to object for strict mode
   3025     // functions.
   3026     __ mov(scratch,
   3027            FieldOperand(function, JSFunction::kSharedFunctionInfoOffset));
   3028     __ test_b(FieldOperand(scratch, SharedFunctionInfo::kStrictModeByteOffset),
   3029               Immediate(1 << SharedFunctionInfo::kStrictModeBitWithinByte));
   3030     __ j(not_equal, &receiver_ok, dist);
   3031 
   3032     // Do not transform the receiver to object for builtins.
   3033     __ test_b(FieldOperand(scratch, SharedFunctionInfo::kNativeByteOffset),
   3034               Immediate(1 << SharedFunctionInfo::kNativeBitWithinByte));
   3035     __ j(not_equal, &receiver_ok, dist);
   3036   }
   3037 
   3038   // Normal function. Replace undefined or null with global receiver.
   3039   __ cmp(receiver, factory()->null_value());
   3040   __ j(equal, &global_object, Label::kNear);
   3041   __ cmp(receiver, factory()->undefined_value());
   3042   __ j(equal, &global_object, Label::kNear);
   3043 
   3044   // The receiver should be a JS object.
   3045   __ test(receiver, Immediate(kSmiTagMask));
   3046   DeoptimizeIf(equal, instr, DeoptimizeReason::kSmi);
   3047   __ CmpObjectType(receiver, FIRST_JS_RECEIVER_TYPE, scratch);
   3048   DeoptimizeIf(below, instr, DeoptimizeReason::kNotAJavaScriptObject);
   3049 
   3050   __ jmp(&receiver_ok, Label::kNear);
   3051   __ bind(&global_object);
   3052   __ mov(receiver, FieldOperand(function, JSFunction::kContextOffset));
   3053   __ mov(receiver, ContextOperand(receiver, Context::NATIVE_CONTEXT_INDEX));
   3054   __ mov(receiver, ContextOperand(receiver, Context::GLOBAL_PROXY_INDEX));
   3055   __ bind(&receiver_ok);
   3056 }
   3057 
   3058 
   3059 void LCodeGen::DoApplyArguments(LApplyArguments* instr) {
   3060   Register receiver = ToRegister(instr->receiver());
   3061   Register function = ToRegister(instr->function());
   3062   Register length = ToRegister(instr->length());
   3063   Register elements = ToRegister(instr->elements());
   3064   DCHECK(receiver.is(eax));  // Used for parameter count.
   3065   DCHECK(function.is(edi));  // Required by InvokeFunction.
   3066   DCHECK(ToRegister(instr->result()).is(eax));
   3067 
   3068   // Copy the arguments to this function possibly from the
   3069   // adaptor frame below it.
   3070   const uint32_t kArgumentsLimit = 1 * KB;
   3071   __ cmp(length, kArgumentsLimit);
   3072   DeoptimizeIf(above, instr, DeoptimizeReason::kTooManyArguments);
   3073 
   3074   __ push(receiver);
   3075   __ mov(receiver, length);
   3076 
   3077   // Loop through the arguments pushing them onto the execution
   3078   // stack.
   3079   Label invoke, loop;
   3080   // length is a small non-negative integer, due to the test above.
   3081   __ test(length, Operand(length));
   3082   __ j(zero, &invoke, Label::kNear);
   3083   __ bind(&loop);
   3084   __ push(Operand(elements, length, times_pointer_size, 1 * kPointerSize));
   3085   __ dec(length);
   3086   __ j(not_zero, &loop);
   3087 
   3088   // Invoke the function.
   3089   __ bind(&invoke);
   3090 
   3091   InvokeFlag flag = CALL_FUNCTION;
   3092   if (instr->hydrogen()->tail_call_mode() == TailCallMode::kAllow) {
   3093     DCHECK(!info()->saves_caller_doubles());
   3094     // TODO(ishell): drop current frame before pushing arguments to the stack.
   3095     flag = JUMP_FUNCTION;
   3096     ParameterCount actual(eax);
   3097     // It is safe to use ebx, ecx and edx as scratch registers here given that
   3098     // 1) we are not going to return to caller function anyway,
   3099     // 2) ebx (expected arguments count) and edx (new.target) will be
   3100     //    initialized below.
   3101     PrepareForTailCall(actual, ebx, ecx, edx);
   3102   }
   3103 
   3104   DCHECK(instr->HasPointerMap());
   3105   LPointerMap* pointers = instr->pointer_map();
   3106   SafepointGenerator safepoint_generator(this, pointers, Safepoint::kLazyDeopt);
   3107   ParameterCount actual(eax);
   3108   __ InvokeFunction(function, no_reg, actual, flag, safepoint_generator);
   3109 }
   3110 
   3111 
   3112 void LCodeGen::DoDebugBreak(LDebugBreak* instr) {
   3113   __ int3();
   3114 }
   3115 
   3116 
   3117 void LCodeGen::DoPushArgument(LPushArgument* instr) {
   3118   LOperand* argument = instr->value();
   3119   EmitPushTaggedOperand(argument);
   3120 }
   3121 
   3122 
   3123 void LCodeGen::DoDrop(LDrop* instr) {
   3124   __ Drop(instr->count());
   3125 }
   3126 
   3127 
   3128 void LCodeGen::DoThisFunction(LThisFunction* instr) {
   3129   Register result = ToRegister(instr->result());
   3130   __ mov(result, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
   3131 }
   3132 
   3133 
   3134 void LCodeGen::DoContext(LContext* instr) {
   3135   Register result = ToRegister(instr->result());
   3136   if (info()->IsOptimizing()) {
   3137     __ mov(result, Operand(ebp, StandardFrameConstants::kContextOffset));
   3138   } else {
   3139     // If there is no frame, the context must be in esi.
   3140     DCHECK(result.is(esi));
   3141   }
   3142 }
   3143 
   3144 
   3145 void LCodeGen::DoDeclareGlobals(LDeclareGlobals* instr) {
   3146   DCHECK(ToRegister(instr->context()).is(esi));
   3147   __ push(Immediate(instr->hydrogen()->pairs()));
   3148   __ push(Immediate(Smi::FromInt(instr->hydrogen()->flags())));
   3149   __ push(Immediate(instr->hydrogen()->feedback_vector()));
   3150   CallRuntime(Runtime::kDeclareGlobals, instr);
   3151 }
   3152 
   3153 void LCodeGen::CallKnownFunction(Handle<JSFunction> function,
   3154                                  int formal_parameter_count, int arity,
   3155                                  bool is_tail_call, LInstruction* instr) {
   3156   bool dont_adapt_arguments =
   3157       formal_parameter_count == SharedFunctionInfo::kDontAdaptArgumentsSentinel;
   3158   bool can_invoke_directly =
   3159       dont_adapt_arguments || formal_parameter_count == arity;
   3160 
   3161   Register function_reg = edi;
   3162 
   3163   if (can_invoke_directly) {
   3164     // Change context.
   3165     __ mov(esi, FieldOperand(function_reg, JSFunction::kContextOffset));
   3166 
   3167     // Always initialize new target and number of actual arguments.
   3168     __ mov(edx, factory()->undefined_value());
   3169     __ mov(eax, arity);
   3170 
   3171     bool is_self_call = function.is_identical_to(info()->closure());
   3172 
   3173     // Invoke function directly.
   3174     if (is_self_call) {
   3175       Handle<Code> self(reinterpret_cast<Code**>(__ CodeObject().location()));
   3176       if (is_tail_call) {
   3177         __ Jump(self, RelocInfo::CODE_TARGET);
   3178       } else {
   3179         __ Call(self, RelocInfo::CODE_TARGET);
   3180       }
   3181     } else {
   3182       Operand target = FieldOperand(function_reg, JSFunction::kCodeEntryOffset);
   3183       if (is_tail_call) {
   3184         __ jmp(target);
   3185       } else {
   3186         __ call(target);
   3187       }
   3188     }
   3189 
   3190     if (!is_tail_call) {
   3191       // Set up deoptimization.
   3192       RecordSafepointWithLazyDeopt(instr, RECORD_SIMPLE_SAFEPOINT);
   3193     }
   3194   } else {
   3195     // We need to adapt arguments.
   3196     LPointerMap* pointers = instr->pointer_map();
   3197     SafepointGenerator generator(
   3198         this, pointers, Safepoint::kLazyDeopt);
   3199     ParameterCount actual(arity);
   3200     ParameterCount expected(formal_parameter_count);
   3201     InvokeFlag flag = is_tail_call ? JUMP_FUNCTION : CALL_FUNCTION;
   3202     __ InvokeFunction(function_reg, expected, actual, flag, generator);
   3203   }
   3204 }
   3205 
   3206 
   3207 void LCodeGen::DoCallWithDescriptor(LCallWithDescriptor* instr) {
   3208   DCHECK(ToRegister(instr->result()).is(eax));
   3209 
   3210   if (instr->hydrogen()->IsTailCall()) {
   3211     if (NeedsEagerFrame()) __ leave();
   3212 
   3213     if (instr->target()->IsConstantOperand()) {
   3214       LConstantOperand* target = LConstantOperand::cast(instr->target());
   3215       Handle<Code> code = Handle<Code>::cast(ToHandle(target));
   3216       __ jmp(code, RelocInfo::CODE_TARGET);
   3217     } else {
   3218       DCHECK(instr->target()->IsRegister());
   3219       Register target = ToRegister(instr->target());
   3220       __ add(target, Immediate(Code::kHeaderSize - kHeapObjectTag));
   3221       __ jmp(target);
   3222     }
   3223   } else {
   3224     LPointerMap* pointers = instr->pointer_map();
   3225     SafepointGenerator generator(this, pointers, Safepoint::kLazyDeopt);
   3226 
   3227     if (instr->target()->IsConstantOperand()) {
   3228       LConstantOperand* target = LConstantOperand::cast(instr->target());
   3229       Handle<Code> code = Handle<Code>::cast(ToHandle(target));
   3230       generator.BeforeCall(__ CallSize(code, RelocInfo::CODE_TARGET));
   3231       __ call(code, RelocInfo::CODE_TARGET);
   3232     } else {
   3233       DCHECK(instr->target()->IsRegister());
   3234       Register target = ToRegister(instr->target());
   3235       generator.BeforeCall(__ CallSize(Operand(target)));
   3236       __ add(target, Immediate(Code::kHeaderSize - kHeapObjectTag));
   3237       __ call(target);
   3238     }
   3239     generator.AfterCall();
   3240   }
   3241 }
   3242 
   3243 
   3244 void LCodeGen::DoDeferredMathAbsTaggedHeapNumber(LMathAbs* instr) {
   3245   Register input_reg = ToRegister(instr->value());
   3246   __ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
   3247          factory()->heap_number_map());
   3248   DeoptimizeIf(not_equal, instr, DeoptimizeReason::kNotAHeapNumber);
   3249 
   3250   Label slow, allocated, done;
   3251   uint32_t available_regs = eax.bit() | ecx.bit() | edx.bit() | ebx.bit();
   3252   available_regs &= ~input_reg.bit();
   3253   if (instr->context()->IsRegister()) {
   3254     // Make sure that the context isn't overwritten in the AllocateHeapNumber
   3255     // macro below.
   3256     available_regs &= ~ToRegister(instr->context()).bit();
   3257   }
   3258 
   3259   Register tmp =
   3260       Register::from_code(base::bits::CountTrailingZeros32(available_regs));
   3261   available_regs &= ~tmp.bit();
   3262   Register tmp2 =
   3263       Register::from_code(base::bits::CountTrailingZeros32(available_regs));
   3264 
   3265   // Preserve the value of all registers.
   3266   PushSafepointRegistersScope scope(this);
   3267 
   3268   __ mov(tmp, FieldOperand(input_reg, HeapNumber::kExponentOffset));
   3269   // Check the sign of the argument. If the argument is positive, just
   3270   // return it. We do not need to patch the stack since |input| and
   3271   // |result| are the same register and |input| will be restored
   3272   // unchanged by popping safepoint registers.
   3273   __ test(tmp, Immediate(HeapNumber::kSignMask));
   3274   __ j(zero, &done, Label::kNear);
   3275 
   3276   __ AllocateHeapNumber(tmp, tmp2, no_reg, &slow);
   3277   __ jmp(&allocated, Label::kNear);
   3278 
   3279   // Slow case: Call the runtime system to do the number allocation.
   3280   __ bind(&slow);
   3281   CallRuntimeFromDeferred(Runtime::kAllocateHeapNumber, 0,
   3282                           instr, instr->context());
   3283   // Set the pointer to the new heap number in tmp.
   3284   if (!tmp.is(eax)) __ mov(tmp, eax);
   3285   // Restore input_reg after call to runtime.
   3286   __ LoadFromSafepointRegisterSlot(input_reg, input_reg);
   3287 
   3288   __ bind(&allocated);
   3289   __ mov(tmp2, FieldOperand(input_reg, HeapNumber::kExponentOffset));
   3290   __ and_(tmp2, ~HeapNumber::kSignMask);
   3291   __ mov(FieldOperand(tmp, HeapNumber::kExponentOffset), tmp2);
   3292   __ mov(tmp2, FieldOperand(input_reg, HeapNumber::kMantissaOffset));
   3293   __ mov(FieldOperand(tmp, HeapNumber::kMantissaOffset), tmp2);
   3294   __ StoreToSafepointRegisterSlot(input_reg, tmp);
   3295 
   3296   __ bind(&done);
   3297 }
   3298 
   3299 
   3300 void LCodeGen::EmitIntegerMathAbs(LMathAbs* instr) {
   3301   Register input_reg = ToRegister(instr->value());
   3302   __ test(input_reg, Operand(input_reg));
   3303   Label is_positive;
   3304   __ j(not_sign, &is_positive, Label::kNear);
   3305   __ neg(input_reg);  // Sets flags.
   3306   DeoptimizeIf(negative, instr, DeoptimizeReason::kOverflow);
   3307   __ bind(&is_positive);
   3308 }
   3309 
   3310 
   3311 void LCodeGen::DoMathAbs(LMathAbs* instr) {
   3312   // Class for deferred case.
   3313   class DeferredMathAbsTaggedHeapNumber final : public LDeferredCode {
   3314    public:
   3315     DeferredMathAbsTaggedHeapNumber(LCodeGen* codegen,
   3316                                     LMathAbs* instr,
   3317                                     const X87Stack& x87_stack)
   3318         : LDeferredCode(codegen, x87_stack), instr_(instr) { }
   3319     void Generate() override {
   3320       codegen()->DoDeferredMathAbsTaggedHeapNumber(instr_);
   3321     }
   3322     LInstruction* instr() override { return instr_; }
   3323 
   3324    private:
   3325     LMathAbs* instr_;
   3326   };
   3327 
   3328   DCHECK(instr->value()->Equals(instr->result()));
   3329   Representation r = instr->hydrogen()->value()->representation();
   3330 
   3331   if (r.IsDouble()) {
   3332     X87Register value = ToX87Register(instr->value());
   3333     X87Fxch(value);
   3334     __ fabs();
   3335   } else if (r.IsSmiOrInteger32()) {
   3336     EmitIntegerMathAbs(instr);
   3337   } else {  // Tagged case.
   3338     DeferredMathAbsTaggedHeapNumber* deferred =
   3339         new(zone()) DeferredMathAbsTaggedHeapNumber(this, instr, x87_stack_);
   3340     Register input_reg = ToRegister(instr->value());
   3341     // Smi check.
   3342     __ JumpIfNotSmi(input_reg, deferred->entry());
   3343     EmitIntegerMathAbs(instr);
   3344     __ bind(deferred->exit());
   3345   }
   3346 }
   3347 
   3348 
   3349 void LCodeGen::DoMathFloor(LMathFloor* instr) {
   3350   Register output_reg = ToRegister(instr->result());
   3351   X87Register input_reg = ToX87Register(instr->value());
   3352   X87Fxch(input_reg);
   3353 
   3354   Label not_minus_zero, done;
   3355   // Deoptimize on unordered.
   3356   __ fldz();
   3357   __ fld(1);
   3358   __ FCmp();
   3359   DeoptimizeIf(parity_even, instr, DeoptimizeReason::kNaN);
   3360   __ j(below, &not_minus_zero, Label::kNear);
   3361 
   3362   if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
   3363     // Check for negative zero.
   3364     __ j(not_equal, &not_minus_zero, Label::kNear);
   3365     // +- 0.0.
   3366     __ fld(0);
   3367     __ FXamSign();
   3368     DeoptimizeIf(not_zero, instr, DeoptimizeReason::kMinusZero);
   3369     __ Move(output_reg, Immediate(0));
   3370     __ jmp(&done, Label::kFar);
   3371   }
   3372 
   3373   // Positive input.
   3374   // rc=01B, round down.
   3375   __ bind(&not_minus_zero);
   3376   __ fnclex();
   3377   __ X87SetRC(0x0400);
   3378   __ sub(esp, Immediate(kPointerSize));
   3379   __ fist_s(Operand(esp, 0));
   3380   __ pop(output_reg);
   3381   __ X87SetRC(0x0000);
   3382   __ X87CheckIA();
   3383   DeoptimizeIf(equal, instr, DeoptimizeReason::kOverflow);
   3384   __ fnclex();
   3385   __ X87SetRC(0x0000);
   3386   __ bind(&done);
   3387 }
   3388 
   3389 
   3390 void LCodeGen::DoMathRound(LMathRound* instr) {
   3391   X87Register input_reg = ToX87Register(instr->value());
   3392   Register result = ToRegister(instr->result());
   3393   X87Fxch(input_reg);
   3394   Label below_one_half, below_minus_one_half, done;
   3395 
   3396   ExternalReference one_half = ExternalReference::address_of_one_half();
   3397   ExternalReference minus_one_half =
   3398       ExternalReference::address_of_minus_one_half();
   3399 
   3400   __ fld_d(Operand::StaticVariable(one_half));
   3401   __ fld(1);
   3402   __ FCmp();
   3403   __ j(carry, &below_one_half);
   3404 
   3405   // Use rounds towards zero, since 0.5 <= x, we use floor(0.5 + x)
   3406   __ fld(0);
   3407   __ fadd_d(Operand::StaticVariable(one_half));
   3408   // rc=11B, round toward zero.
   3409   __ X87SetRC(0x0c00);
   3410   __ sub(esp, Immediate(kPointerSize));
   3411   // Clear exception bits.
   3412   __ fnclex();
   3413   __ fistp_s(MemOperand(esp, 0));
   3414   // Restore round mode.
   3415   __ X87SetRC(0x0000);
   3416   // Check overflow.
   3417   __ X87CheckIA();
   3418   __ pop(result);
   3419   DeoptimizeIf(equal, instr, DeoptimizeReason::kConversionOverflow);
   3420   __ fnclex();
   3421   // Restore round mode.
   3422   __ X87SetRC(0x0000);
   3423   __ jmp(&done);
   3424 
   3425   __ bind(&below_one_half);
   3426   __ fld_d(Operand::StaticVariable(minus_one_half));
   3427   __ fld(1);
   3428   __ FCmp();
   3429   __ j(carry, &below_minus_one_half);
   3430   // We return 0 for the input range [+0, 0.5[, or [-0.5, 0.5[ if
   3431   // we can ignore the difference between a result of -0 and +0.
   3432   if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
   3433     // If the sign is positive, we return +0.
   3434     __ fld(0);
   3435     __ FXamSign();
   3436     DeoptimizeIf(not_zero, instr, DeoptimizeReason::kMinusZero);
   3437   }
   3438   __ Move(result, Immediate(0));
   3439   __ jmp(&done);
   3440 
   3441   __ bind(&below_minus_one_half);
   3442   __ fld(0);
   3443   __ fadd_d(Operand::StaticVariable(one_half));
   3444   // rc=01B, round down.
   3445   __ X87SetRC(0x0400);
   3446   __ sub(esp, Immediate(kPointerSize));
   3447   // Clear exception bits.
   3448   __ fnclex();
   3449   __ fistp_s(MemOperand(esp, 0));
   3450   // Restore round mode.
   3451   __ X87SetRC(0x0000);
   3452   // Check overflow.
   3453   __ X87CheckIA();
   3454   __ pop(result);
   3455   DeoptimizeIf(equal, instr, DeoptimizeReason::kConversionOverflow);
   3456   __ fnclex();
   3457   // Restore round mode.
   3458   __ X87SetRC(0x0000);
   3459 
   3460   __ bind(&done);
   3461 }
   3462 
   3463 
   3464 void LCodeGen::DoMathFround(LMathFround* instr) {
   3465   X87Register input_reg = ToX87Register(instr->value());
   3466   X87Fxch(input_reg);
   3467   __ sub(esp, Immediate(kPointerSize));
   3468   __ fstp_s(MemOperand(esp, 0));
   3469   X87Fld(MemOperand(esp, 0), kX87FloatOperand);
   3470   __ add(esp, Immediate(kPointerSize));
   3471 }
   3472 
   3473 
   3474 void LCodeGen::DoMathSqrt(LMathSqrt* instr) {
   3475   X87Register input_reg = ToX87Register(instr->value());
   3476   __ X87SetFPUCW(0x027F);
   3477   X87Fxch(input_reg);
   3478   __ fsqrt();
   3479   __ X87SetFPUCW(0x037F);
   3480 }
   3481 
   3482 
   3483 void LCodeGen::DoMathPowHalf(LMathPowHalf* instr) {
   3484   X87Register input_reg = ToX87Register(instr->value());
   3485   DCHECK(ToX87Register(instr->result()).is(input_reg));
   3486   X87Fxch(input_reg);
   3487   // Note that according to ECMA-262 15.8.2.13:
   3488   // Math.pow(-Infinity, 0.5) == Infinity
   3489   // Math.sqrt(-Infinity) == NaN
   3490   Label done, sqrt;
   3491   // Check base for -Infinity. C3 == 0, C2 == 1, C1 == 1 and C0 == 1
   3492   __ fxam();
   3493   __ push(eax);
   3494   __ fnstsw_ax();
   3495   __ and_(eax, Immediate(0x4700));
   3496   __ cmp(eax, Immediate(0x0700));
   3497   __ j(not_equal, &sqrt, Label::kNear);
   3498   // If input is -Infinity, return Infinity.
   3499   __ fchs();
   3500   __ jmp(&done, Label::kNear);
   3501 
   3502   // Square root.
   3503   __ bind(&sqrt);
   3504   __ fldz();
   3505   __ faddp();  // Convert -0 to +0.
   3506   __ fsqrt();
   3507   __ bind(&done);
   3508   __ pop(eax);
   3509 }
   3510 
   3511 
   3512 void LCodeGen::DoPower(LPower* instr) {
   3513   Representation exponent_type = instr->hydrogen()->right()->representation();
   3514   X87Register result = ToX87Register(instr->result());
   3515   // Having marked this as a call, we can use any registers.
   3516   X87Register base = ToX87Register(instr->left());
   3517   ExternalReference one_half = ExternalReference::address_of_one_half();
   3518 
   3519   if (exponent_type.IsSmi()) {
   3520     Register exponent = ToRegister(instr->right());
   3521     X87LoadForUsage(base);
   3522     __ SmiUntag(exponent);
   3523     __ push(exponent);
   3524     __ fild_s(MemOperand(esp, 0));
   3525     __ pop(exponent);
   3526   } else if (exponent_type.IsTagged()) {
   3527     Register exponent = ToRegister(instr->right());
   3528     Register temp = exponent.is(ecx) ? eax : ecx;
   3529     Label no_deopt, done;
   3530     X87LoadForUsage(base);
   3531     __ JumpIfSmi(exponent, &no_deopt);
   3532     __ CmpObjectType(exponent, HEAP_NUMBER_TYPE, temp);
   3533     DeoptimizeIf(not_equal, instr, DeoptimizeReason::kNotAHeapNumber);
   3534     // Heap number(double)
   3535     __ fld_d(FieldOperand(exponent, HeapNumber::kValueOffset));
   3536     __ jmp(&done);
   3537     // SMI
   3538     __ bind(&no_deopt);
   3539     __ SmiUntag(exponent);
   3540     __ push(exponent);
   3541     __ fild_s(MemOperand(esp, 0));
   3542     __ pop(exponent);
   3543     __ bind(&done);
   3544   } else if (exponent_type.IsInteger32()) {
   3545     Register exponent = ToRegister(instr->right());
   3546     X87LoadForUsage(base);
   3547     __ push(exponent);
   3548     __ fild_s(MemOperand(esp, 0));
   3549     __ pop(exponent);
   3550   } else {
   3551     DCHECK(exponent_type.IsDouble());
   3552     X87Register exponent_double = ToX87Register(instr->right());
   3553     X87LoadForUsage(base, exponent_double);
   3554   }
   3555 
   3556   // FP data stack {base, exponent(TOS)}.
   3557   // Handle (exponent==+-0.5 && base == -0).
   3558   Label not_plus_0;
   3559   __ fld(0);
   3560   __ fabs();
   3561   X87Fld(Operand::StaticVariable(one_half), kX87DoubleOperand);
   3562   __ FCmp();
   3563   __ j(parity_even, &not_plus_0, Label::kNear);  // NaN.
   3564   __ j(not_equal, &not_plus_0, Label::kNear);
   3565   __ fldz();
   3566   // FP data stack {base, exponent(TOS), zero}.
   3567   __ faddp(2);
   3568   __ bind(&not_plus_0);
   3569 
   3570   {
   3571     __ PrepareCallCFunction(4, eax);
   3572     __ fstp_d(MemOperand(esp, kDoubleSize));  // Exponent value.
   3573     __ fstp_d(MemOperand(esp, 0));            // Base value.
   3574     X87PrepareToWrite(result);
   3575     __ CallCFunction(ExternalReference::power_double_double_function(isolate()),
   3576                      4);
   3577     // Return value is in st(0) on ia32.
   3578     X87CommitWrite(result);
   3579   }
   3580 }
   3581 
   3582 
   3583 void LCodeGen::DoMathLog(LMathLog* instr) {
   3584   DCHECK(instr->value()->Equals(instr->result()));
   3585   X87Register result = ToX87Register(instr->result());
   3586   X87Register input_reg = ToX87Register(instr->value());
   3587   X87Fxch(input_reg);
   3588 
   3589   // Pass one double as argument on the stack.
   3590   __ PrepareCallCFunction(2, eax);
   3591   __ fstp_d(MemOperand(esp, 0));
   3592   X87PrepareToWrite(result);
   3593   __ CallCFunction(ExternalReference::ieee754_log_function(isolate()), 2);
   3594   // Return value is in st(0) on ia32.
   3595   X87CommitWrite(result);
   3596 }
   3597 
   3598 
   3599 void LCodeGen::DoMathClz32(LMathClz32* instr) {
   3600   Register input = ToRegister(instr->value());
   3601   Register result = ToRegister(instr->result());
   3602 
   3603   __ Lzcnt(result, input);
   3604 }
   3605 
   3606 void LCodeGen::DoMathCos(LMathCos* instr) {
   3607   X87Register result = ToX87Register(instr->result());
   3608   X87Register input_reg = ToX87Register(instr->value());
   3609   __ fld(x87_stack_.st(input_reg));
   3610 
   3611   // Pass one double as argument on the stack.
   3612   __ PrepareCallCFunction(2, eax);
   3613   __ fstp_d(MemOperand(esp, 0));
   3614   X87PrepareToWrite(result);
   3615   __ X87SetFPUCW(0x027F);
   3616   __ CallCFunction(ExternalReference::ieee754_cos_function(isolate()), 2);
   3617   __ X87SetFPUCW(0x037F);
   3618   // Return value is in st(0) on ia32.
   3619   X87CommitWrite(result);
   3620 }
   3621 
   3622 void LCodeGen::DoMathSin(LMathSin* instr) {
   3623   X87Register result = ToX87Register(instr->result());
   3624   X87Register input_reg = ToX87Register(instr->value());
   3625   __ fld(x87_stack_.st(input_reg));
   3626 
   3627   // Pass one double as argument on the stack.
   3628   __ PrepareCallCFunction(2, eax);
   3629   __ fstp_d(MemOperand(esp, 0));
   3630   X87PrepareToWrite(result);
   3631   __ X87SetFPUCW(0x027F);
   3632   __ CallCFunction(ExternalReference::ieee754_sin_function(isolate()), 2);
   3633   __ X87SetFPUCW(0x037F);
   3634   // Return value is in st(0) on ia32.
   3635   X87CommitWrite(result);
   3636 }
   3637 
   3638 void LCodeGen::DoMathExp(LMathExp* instr) {
   3639   X87Register result = ToX87Register(instr->result());
   3640   X87Register input_reg = ToX87Register(instr->value());
   3641   __ fld(x87_stack_.st(input_reg));
   3642 
   3643   // Pass one double as argument on the stack.
   3644   __ PrepareCallCFunction(2, eax);
   3645   __ fstp_d(MemOperand(esp, 0));
   3646   X87PrepareToWrite(result);
   3647   __ CallCFunction(ExternalReference::ieee754_exp_function(isolate()), 2);
   3648   // Return value is in st(0) on ia32.
   3649   X87CommitWrite(result);
   3650 }
   3651 
   3652 void LCodeGen::PrepareForTailCall(const ParameterCount& actual,
   3653                                   Register scratch1, Register scratch2,
   3654                                   Register scratch3) {
   3655 #if DEBUG
   3656   if (actual.is_reg()) {
   3657     DCHECK(!AreAliased(actual.reg(), scratch1, scratch2, scratch3));
   3658   } else {
   3659     DCHECK(!AreAliased(scratch1, scratch2, scratch3));
   3660   }
   3661 #endif
   3662   if (FLAG_code_comments) {
   3663     if (actual.is_reg()) {
   3664       Comment(";;; PrepareForTailCall, actual: %s {",
   3665               RegisterConfiguration::Crankshaft()->GetGeneralRegisterName(
   3666                   actual.reg().code()));
   3667     } else {
   3668       Comment(";;; PrepareForTailCall, actual: %d {", actual.immediate());
   3669     }
   3670   }
   3671 
   3672   // Check if next frame is an arguments adaptor frame.
   3673   Register caller_args_count_reg = scratch1;
   3674   Label no_arguments_adaptor, formal_parameter_count_loaded;
   3675   __ mov(scratch2, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
   3676   __ cmp(Operand(scratch2, StandardFrameConstants::kContextOffset),
   3677          Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
   3678   __ j(not_equal, &no_arguments_adaptor, Label::kNear);
   3679 
   3680   // Drop current frame and load arguments count from arguments adaptor frame.
   3681   __ mov(ebp, scratch2);
   3682   __ mov(caller_args_count_reg,
   3683          Operand(ebp, ArgumentsAdaptorFrameConstants::kLengthOffset));
   3684   __ SmiUntag(caller_args_count_reg);
   3685   __ jmp(&formal_parameter_count_loaded, Label::kNear);
   3686 
   3687   __ bind(&no_arguments_adaptor);
   3688   // Load caller's formal parameter count.
   3689   __ mov(caller_args_count_reg,
   3690          Immediate(info()->literal()->parameter_count()));
   3691 
   3692   __ bind(&formal_parameter_count_loaded);
   3693   __ PrepareForTailCall(actual, caller_args_count_reg, scratch2, scratch3,
   3694                         ReturnAddressState::kNotOnStack, 0);
   3695   Comment(";;; }");
   3696 }
   3697 
   3698 void LCodeGen::DoInvokeFunction(LInvokeFunction* instr) {
   3699   HInvokeFunction* hinstr = instr->hydrogen();
   3700   DCHECK(ToRegister(instr->context()).is(esi));
   3701   DCHECK(ToRegister(instr->function()).is(edi));
   3702   DCHECK(instr->HasPointerMap());
   3703 
   3704   bool is_tail_call = hinstr->tail_call_mode() == TailCallMode::kAllow;
   3705 
   3706   if (is_tail_call) {
   3707     DCHECK(!info()->saves_caller_doubles());
   3708     ParameterCount actual(instr->arity());
   3709     // It is safe to use ebx, ecx and edx as scratch registers here given that
   3710     // 1) we are not going to return to caller function anyway,
   3711     // 2) ebx (expected arguments count) and edx (new.target) will be
   3712     //    initialized below.
   3713     PrepareForTailCall(actual, ebx, ecx, edx);
   3714   }
   3715 
   3716   Handle<JSFunction> known_function = hinstr->known_function();
   3717   if (known_function.is_null()) {
   3718     LPointerMap* pointers = instr->pointer_map();
   3719     SafepointGenerator generator(this, pointers, Safepoint::kLazyDeopt);
   3720     ParameterCount actual(instr->arity());
   3721     InvokeFlag flag = is_tail_call ? JUMP_FUNCTION : CALL_FUNCTION;
   3722     __ InvokeFunction(edi, no_reg, actual, flag, generator);
   3723   } else {
   3724     CallKnownFunction(known_function, hinstr->formal_parameter_count(),
   3725                       instr->arity(), is_tail_call, instr);
   3726   }
   3727 }
   3728 
   3729 
   3730 void LCodeGen::DoCallNewArray(LCallNewArray* instr) {
   3731   DCHECK(ToRegister(instr->context()).is(esi));
   3732   DCHECK(ToRegister(instr->constructor()).is(edi));
   3733   DCHECK(ToRegister(instr->result()).is(eax));
   3734 
   3735   __ Move(eax, Immediate(instr->arity()));
   3736   __ mov(ebx, instr->hydrogen()->site());
   3737 
   3738   ElementsKind kind = instr->hydrogen()->elements_kind();
   3739   AllocationSiteOverrideMode override_mode =
   3740       (AllocationSite::GetMode(kind) == TRACK_ALLOCATION_SITE)
   3741           ? DISABLE_ALLOCATION_SITES
   3742           : DONT_OVERRIDE;
   3743 
   3744   if (instr->arity() == 0) {
   3745     ArrayNoArgumentConstructorStub stub(isolate(), kind, override_mode);
   3746     CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
   3747   } else if (instr->arity() == 1) {
   3748     Label done;
   3749     if (IsFastPackedElementsKind(kind)) {
   3750       Label packed_case;
   3751       // We might need a change here
   3752       // look at the first argument
   3753       __ mov(ecx, Operand(esp, 0));
   3754       __ test(ecx, ecx);
   3755       __ j(zero, &packed_case, Label::kNear);
   3756 
   3757       ElementsKind holey_kind = GetHoleyElementsKind(kind);
   3758       ArraySingleArgumentConstructorStub stub(isolate(),
   3759                                               holey_kind,
   3760                                               override_mode);
   3761       CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
   3762       __ jmp(&done, Label::kNear);
   3763       __ bind(&packed_case);
   3764     }
   3765 
   3766     ArraySingleArgumentConstructorStub stub(isolate(), kind, override_mode);
   3767     CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
   3768     __ bind(&done);
   3769   } else {
   3770     ArrayNArgumentsConstructorStub stub(isolate());
   3771     CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
   3772   }
   3773 }
   3774 
   3775 
   3776 void LCodeGen::DoCallRuntime(LCallRuntime* instr) {
   3777   DCHECK(ToRegister(instr->context()).is(esi));
   3778   CallRuntime(instr->function(), instr->arity(), instr, instr->save_doubles());
   3779 }
   3780 
   3781 
   3782 void LCodeGen::DoStoreCodeEntry(LStoreCodeEntry* instr) {
   3783   Register function = ToRegister(instr->function());
   3784   Register code_object = ToRegister(instr->code_object());
   3785   __ lea(code_object, FieldOperand(code_object, Code::kHeaderSize));
   3786   __ mov(FieldOperand(function, JSFunction::kCodeEntryOffset), code_object);
   3787 }
   3788 
   3789 
   3790 void LCodeGen::DoInnerAllocatedObject(LInnerAllocatedObject* instr) {
   3791   Register result = ToRegister(instr->result());
   3792   Register base = ToRegister(instr->base_object());
   3793   if (instr->offset()->IsConstantOperand()) {
   3794     LConstantOperand* offset = LConstantOperand::cast(instr->offset());
   3795     __ lea(result, Operand(base, ToInteger32(offset)));
   3796   } else {
   3797     Register offset = ToRegister(instr->offset());
   3798     __ lea(result, Operand(base, offset, times_1, 0));
   3799   }
   3800 }
   3801 
   3802 
   3803 void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
   3804   Representation representation = instr->hydrogen()->field_representation();
   3805 
   3806   HObjectAccess access = instr->hydrogen()->access();
   3807   int offset = access.offset();
   3808 
   3809   if (access.IsExternalMemory()) {
   3810     DCHECK(!instr->hydrogen()->NeedsWriteBarrier());
   3811     MemOperand operand = instr->object()->IsConstantOperand()
   3812         ? MemOperand::StaticVariable(
   3813             ToExternalReference(LConstantOperand::cast(instr->object())))
   3814         : MemOperand(ToRegister(instr->object()), offset);
   3815     if (instr->value()->IsConstantOperand()) {
   3816       LConstantOperand* operand_value = LConstantOperand::cast(instr->value());
   3817       __ mov(operand, Immediate(ToInteger32(operand_value)));
   3818     } else {
   3819       Register value = ToRegister(instr->value());
   3820       __ Store(value, operand, representation);
   3821     }
   3822     return;
   3823   }
   3824 
   3825   Register object = ToRegister(instr->object());
   3826   __ AssertNotSmi(object);
   3827   DCHECK(!representation.IsSmi() ||
   3828          !instr->value()->IsConstantOperand() ||
   3829          IsSmi(LConstantOperand::cast(instr->value())));
   3830   if (representation.IsDouble()) {
   3831     DCHECK(access.IsInobject());
   3832     DCHECK(!instr->hydrogen()->has_transition());
   3833     DCHECK(!instr->hydrogen()->NeedsWriteBarrier());
   3834     X87Register value = ToX87Register(instr->value());
   3835     X87Mov(FieldOperand(object, offset), value);
   3836     return;
   3837   }
   3838 
   3839   if (instr->hydrogen()->has_transition()) {
   3840     Handle<Map> transition = instr->hydrogen()->transition_map();
   3841     AddDeprecationDependency(transition);
   3842     __ mov(FieldOperand(object, HeapObject::kMapOffset), transition);
   3843     if (instr->hydrogen()->NeedsWriteBarrierForMap()) {
   3844       Register temp = ToRegister(instr->temp());
   3845       Register temp_map = ToRegister(instr->temp_map());
   3846       __ mov(temp_map, transition);
   3847       __ mov(FieldOperand(object, HeapObject::kMapOffset), temp_map);
   3848       // Update the write barrier for the map field.
   3849       __ RecordWriteForMap(object, transition, temp_map, temp, kSaveFPRegs);
   3850     }
   3851   }
   3852 
   3853   // Do the store.
   3854   Register write_register = object;
   3855   if (!access.IsInobject()) {
   3856     write_register = ToRegister(instr->temp());
   3857     __ mov(write_register, FieldOperand(object, JSObject::kPropertiesOffset));
   3858   }
   3859 
   3860   MemOperand operand = FieldOperand(write_register, offset);
   3861   if (instr->value()->IsConstantOperand()) {
   3862     LConstantOperand* operand_value = LConstantOperand::cast(instr->value());
   3863     if (operand_value->IsRegister()) {
   3864       Register value = ToRegister(operand_value);
   3865       __ Store(value, operand, representation);
   3866     } else if (representation.IsInteger32() || representation.IsExternal()) {
   3867       Immediate immediate = ToImmediate(operand_value, representation);
   3868       DCHECK(!instr->hydrogen()->NeedsWriteBarrier());
   3869       __ mov(operand, immediate);
   3870     } else {
   3871       Handle<Object> handle_value = ToHandle(operand_value);
   3872       DCHECK(!instr->hydrogen()->NeedsWriteBarrier());
   3873       __ mov(operand, handle_value);
   3874     }
   3875   } else {
   3876     Register value = ToRegister(instr->value());
   3877     __ Store(value, operand, representation);
   3878   }
   3879 
   3880   if (instr->hydrogen()->NeedsWriteBarrier()) {
   3881     Register value = ToRegister(instr->value());
   3882     Register temp = access.IsInobject() ? ToRegister(instr->temp()) : object;
   3883     // Update the write barrier for the object for in-object properties.
   3884     __ RecordWriteField(write_register, offset, value, temp, kSaveFPRegs,
   3885                         EMIT_REMEMBERED_SET,
   3886                         instr->hydrogen()->SmiCheckForWriteBarrier(),
   3887                         instr->hydrogen()->PointersToHereCheckForValue());
   3888   }
   3889 }
   3890 
   3891 
   3892 void LCodeGen::DoBoundsCheck(LBoundsCheck* instr) {
   3893   Condition cc = instr->hydrogen()->allow_equality() ? above : above_equal;
   3894   if (instr->index()->IsConstantOperand()) {
   3895     __ cmp(ToOperand(instr->length()),
   3896            ToImmediate(LConstantOperand::cast(instr->index()),
   3897                        instr->hydrogen()->length()->representation()));
   3898     cc = CommuteCondition(cc);
   3899   } else if (instr->length()->IsConstantOperand()) {
   3900     __ cmp(ToOperand(instr->index()),
   3901            ToImmediate(LConstantOperand::cast(instr->length()),
   3902                        instr->hydrogen()->index()->representation()));
   3903   } else {
   3904     __ cmp(ToRegister(instr->index()), ToOperand(instr->length()));
   3905   }
   3906   if (FLAG_debug_code && instr->hydrogen()->skip_check()) {
   3907     Label done;
   3908     __ j(NegateCondition(cc), &done, Label::kNear);
   3909     __ int3();
   3910     __ bind(&done);
   3911   } else {
   3912     DeoptimizeIf(cc, instr, DeoptimizeReason::kOutOfBounds);
   3913   }
   3914 }
   3915 
   3916 
   3917 void LCodeGen::DoStoreKeyedExternalArray(LStoreKeyed* instr) {
   3918   ElementsKind elements_kind = instr->elements_kind();
   3919   LOperand* key = instr->key();
   3920   if (!key->IsConstantOperand() &&
   3921       ExternalArrayOpRequiresTemp(instr->hydrogen()->key()->representation(),
   3922                                   elements_kind)) {
   3923     __ SmiUntag(ToRegister(key));
   3924   }
   3925   Operand operand(BuildFastArrayOperand(
   3926       instr->elements(),
   3927       key,
   3928       instr->hydrogen()->key()->representation(),
   3929       elements_kind,
   3930       instr->base_offset()));
   3931   if (elements_kind == FLOAT32_ELEMENTS) {
   3932     X87Mov(operand, ToX87Register(instr->value()), kX87FloatOperand);
   3933   } else if (elements_kind == FLOAT64_ELEMENTS) {
   3934     uint64_t int_val = kHoleNanInt64;
   3935     int32_t lower = static_cast<int32_t>(int_val);
   3936     int32_t upper = static_cast<int32_t>(int_val >> (kBitsPerInt));
   3937     Operand operand2 = BuildFastArrayOperand(
   3938         instr->elements(), instr->key(),
   3939         instr->hydrogen()->key()->representation(), elements_kind,
   3940         instr->base_offset() + kPointerSize);
   3941 
   3942     Label no_special_nan_handling, done;
   3943     X87Register value = ToX87Register(instr->value());
   3944     X87Fxch(value);
   3945     __ lea(esp, Operand(esp, -kDoubleSize));
   3946     __ fst_d(MemOperand(esp, 0));
   3947     __ lea(esp, Operand(esp, kDoubleSize));
   3948     int offset = sizeof(kHoleNanUpper32);
   3949     __ cmp(MemOperand(esp, -offset), Immediate(kHoleNanUpper32));
   3950     __ j(not_equal, &no_special_nan_handling, Label::kNear);
   3951     __ mov(operand, Immediate(lower));
   3952     __ mov(operand2, Immediate(upper));
   3953     __ jmp(&done, Label::kNear);
   3954 
   3955     __ bind(&no_special_nan_handling);
   3956     __ fst_d(operand);
   3957     __ bind(&done);
   3958   } else {
   3959     Register value = ToRegister(instr->value());
   3960     switch (elements_kind) {
   3961       case UINT8_ELEMENTS:
   3962       case INT8_ELEMENTS:
   3963       case UINT8_CLAMPED_ELEMENTS:
   3964         __ mov_b(operand, value);
   3965         break;
   3966       case UINT16_ELEMENTS:
   3967       case INT16_ELEMENTS:
   3968         __ mov_w(operand, value);
   3969         break;
   3970       case UINT32_ELEMENTS:
   3971       case INT32_ELEMENTS:
   3972         __ mov(operand, value);
   3973         break;
   3974       case FLOAT32_ELEMENTS:
   3975       case FLOAT64_ELEMENTS:
   3976       case FAST_SMI_ELEMENTS:
   3977       case FAST_ELEMENTS:
   3978       case FAST_DOUBLE_ELEMENTS:
   3979       case FAST_HOLEY_SMI_ELEMENTS:
   3980       case FAST_HOLEY_ELEMENTS:
   3981       case FAST_HOLEY_DOUBLE_ELEMENTS:
   3982       case DICTIONARY_ELEMENTS:
   3983       case FAST_SLOPPY_ARGUMENTS_ELEMENTS:
   3984       case SLOW_SLOPPY_ARGUMENTS_ELEMENTS:
   3985       case FAST_STRING_WRAPPER_ELEMENTS:
   3986       case SLOW_STRING_WRAPPER_ELEMENTS:
   3987       case NO_ELEMENTS:
   3988         UNREACHABLE();
   3989         break;
   3990     }
   3991   }
   3992 }
   3993 
   3994 
   3995 void LCodeGen::DoStoreKeyedFixedDoubleArray(LStoreKeyed* instr) {
   3996   Operand double_store_operand = BuildFastArrayOperand(
   3997       instr->elements(),
   3998       instr->key(),
   3999       instr->hydrogen()->key()->representation(),
   4000       FAST_DOUBLE_ELEMENTS,
   4001       instr->base_offset());
   4002 
   4003   uint64_t int_val = kHoleNanInt64;
   4004   int32_t lower = static_cast<int32_t>(int_val);
   4005   int32_t upper = static_cast<int32_t>(int_val >> (kBitsPerInt));
   4006   Operand double_store_operand2 = BuildFastArrayOperand(
   4007       instr->elements(), instr->key(),
   4008       instr->hydrogen()->key()->representation(), FAST_DOUBLE_ELEMENTS,
   4009       instr->base_offset() + kPointerSize);
   4010 
   4011   if (instr->hydrogen()->IsConstantHoleStore()) {
   4012     // This means we should store the (double) hole. No floating point
   4013     // registers required.
   4014     __ mov(double_store_operand, Immediate(lower));
   4015     __ mov(double_store_operand2, Immediate(upper));
   4016   } else {
   4017     Label no_special_nan_handling, done;
   4018     X87Register value = ToX87Register(instr->value());
   4019     X87Fxch(value);
   4020 
   4021     if (instr->NeedsCanonicalization()) {
   4022       __ fld(0);
   4023       __ fld(0);
   4024       __ FCmp();
   4025       __ j(parity_odd, &no_special_nan_handling, Label::kNear);
   4026       // All NaNs are Canonicalized to 0x7fffffffffffffff
   4027       __ mov(double_store_operand, Immediate(0xffffffff));
   4028       __ mov(double_store_operand2, Immediate(0x7fffffff));
   4029       __ jmp(&done, Label::kNear);
   4030     } else {
   4031       __ lea(esp, Operand(esp, -kDoubleSize));
   4032       __ fst_d(MemOperand(esp, 0));
   4033       __ lea(esp, Operand(esp, kDoubleSize));
   4034       int offset = sizeof(kHoleNanUpper32);
   4035       __ cmp(MemOperand(esp, -offset), Immediate(kHoleNanUpper32));
   4036       __ j(not_equal, &no_special_nan_handling, Label::kNear);
   4037       __ mov(double_store_operand, Immediate(lower));
   4038       __ mov(double_store_operand2, Immediate(upper));
   4039       __ jmp(&done, Label::kNear);
   4040     }
   4041     __ bind(&no_special_nan_handling);
   4042     __ fst_d(double_store_operand);
   4043     __ bind(&done);
   4044   }
   4045 }
   4046 
   4047 
   4048 void LCodeGen::DoStoreKeyedFixedArray(LStoreKeyed* instr) {
   4049   Register elements = ToRegister(instr->elements());
   4050   Register key = instr->key()->IsRegister() ? ToRegister(instr->key()) : no_reg;
   4051 
   4052   Operand operand = BuildFastArrayOperand(
   4053       instr->elements(),
   4054       instr->key(),
   4055       instr->hydrogen()->key()->representation(),
   4056       FAST_ELEMENTS,
   4057       instr->base_offset());
   4058   if (instr->value()->IsRegister()) {
   4059     __ mov(operand, ToRegister(instr->value()));
   4060   } else {
   4061     LConstantOperand* operand_value = LConstantOperand::cast(instr->value());
   4062     if (IsSmi(operand_value)) {
   4063       Immediate immediate = ToImmediate(operand_value, Representation::Smi());
   4064       __ mov(operand, immediate);
   4065     } else {
   4066       DCHECK(!IsInteger32(operand_value));
   4067       Handle<Object> handle_value = ToHandle(operand_value);
   4068       __ mov(operand, handle_value);
   4069     }
   4070   }
   4071 
   4072   if (instr->hydrogen()->NeedsWriteBarrier()) {
   4073     DCHECK(instr->value()->IsRegister());
   4074     Register value = ToRegister(instr->value());
   4075     DCHECK(!instr->key()->IsConstantOperand());
   4076     SmiCheck check_needed =
   4077         instr->hydrogen()->value()->type().IsHeapObject()
   4078           ? OMIT_SMI_CHECK : INLINE_SMI_CHECK;
   4079     // Compute address of modified element and store it into key register.
   4080     __ lea(key, operand);
   4081     __ RecordWrite(elements, key, value, kSaveFPRegs, EMIT_REMEMBERED_SET,
   4082                    check_needed,
   4083                    instr->hydrogen()->PointersToHereCheckForValue());
   4084   }
   4085 }
   4086 
   4087 
   4088 void LCodeGen::DoStoreKeyed(LStoreKeyed* instr) {
   4089   // By cases...external, fast-double, fast
   4090   if (instr->is_fixed_typed_array()) {
   4091     DoStoreKeyedExternalArray(instr);
   4092   } else if (instr->hydrogen()->value()->representation().IsDouble()) {
   4093     DoStoreKeyedFixedDoubleArray(instr);
   4094   } else {
   4095     DoStoreKeyedFixedArray(instr);
   4096   }
   4097 }
   4098 
   4099 
   4100 void LCodeGen::DoTrapAllocationMemento(LTrapAllocationMemento* instr) {
   4101   Register object = ToRegister(instr->object());
   4102   Register temp = ToRegister(instr->temp());
   4103   Label no_memento_found;
   4104   __ TestJSArrayForAllocationMemento(object, temp, &no_memento_found);
   4105   DeoptimizeIf(equal, instr, DeoptimizeReason::kMementoFound);
   4106   __ bind(&no_memento_found);
   4107 }
   4108 
   4109 
   4110 void LCodeGen::DoMaybeGrowElements(LMaybeGrowElements* instr) {
   4111   class DeferredMaybeGrowElements final : public LDeferredCode {
   4112    public:
   4113     DeferredMaybeGrowElements(LCodeGen* codegen,
   4114                               LMaybeGrowElements* instr,
   4115                               const X87Stack& x87_stack)
   4116         : LDeferredCode(codegen, x87_stack), instr_(instr) {}
   4117     void Generate() override { codegen()->DoDeferredMaybeGrowElements(instr_); }
   4118     LInstruction* instr() override { return instr_; }
   4119 
   4120    private:
   4121     LMaybeGrowElements* instr_;
   4122   };
   4123 
   4124   Register result = eax;
   4125   DeferredMaybeGrowElements* deferred =
   4126       new (zone()) DeferredMaybeGrowElements(this, instr, x87_stack_);
   4127   LOperand* key = instr->key();
   4128   LOperand* current_capacity = instr->current_capacity();
   4129 
   4130   DCHECK(instr->hydrogen()->key()->representation().IsInteger32());
   4131   DCHECK(instr->hydrogen()->current_capacity()->representation().IsInteger32());
   4132   DCHECK(key->IsConstantOperand() || key->IsRegister());
   4133   DCHECK(current_capacity->IsConstantOperand() ||
   4134          current_capacity->IsRegister());
   4135 
   4136   if (key->IsConstantOperand() && current_capacity->IsConstantOperand()) {
   4137     int32_t constant_key = ToInteger32(LConstantOperand::cast(key));
   4138     int32_t constant_capacity =
   4139         ToInteger32(LConstantOperand::cast(current_capacity));
   4140     if (constant_key >= constant_capacity) {
   4141       // Deferred case.
   4142       __ jmp(deferred->entry());
   4143     }
   4144   } else if (key->IsConstantOperand()) {
   4145     int32_t constant_key = ToInteger32(LConstantOperand::cast(key));
   4146     __ cmp(ToOperand(current_capacity), Immediate(constant_key));
   4147     __ j(less_equal, deferred->entry());
   4148   } else if (current_capacity->IsConstantOperand()) {
   4149     int32_t constant_capacity =
   4150         ToInteger32(LConstantOperand::cast(current_capacity));
   4151     __ cmp(ToRegister(key), Immediate(constant_capacity));
   4152     __ j(greater_equal, deferred->entry());
   4153   } else {
   4154     __ cmp(ToRegister(key), ToRegister(current_capacity));
   4155     __ j(greater_equal, deferred->entry());
   4156   }
   4157 
   4158   __ mov(result, ToOperand(instr->elements()));
   4159   __ bind(deferred->exit());
   4160 }
   4161 
   4162 
   4163 void LCodeGen::DoDeferredMaybeGrowElements(LMaybeGrowElements* instr) {
   4164   // TODO(3095996): Get rid of this. For now, we need to make the
   4165   // result register contain a valid pointer because it is already
   4166   // contained in the register pointer map.
   4167   Register result = eax;
   4168   __ Move(result, Immediate(0));
   4169 
   4170   // We have to call a stub.
   4171   {
   4172     PushSafepointRegistersScope scope(this);
   4173     if (instr->object()->IsRegister()) {
   4174       __ Move(result, ToRegister(instr->object()));
   4175     } else {
   4176       __ mov(result, ToOperand(instr->object()));
   4177     }
   4178 
   4179     LOperand* key = instr->key();
   4180     if (key->IsConstantOperand()) {
   4181       LConstantOperand* constant_key = LConstantOperand::cast(key);
   4182       int32_t int_key = ToInteger32(constant_key);
   4183       if (Smi::IsValid(int_key)) {
   4184         __ mov(ebx, Immediate(Smi::FromInt(int_key)));
   4185       } else {
   4186         // We should never get here at runtime because there is a smi check on
   4187         // the key before this point.
   4188         __ int3();
   4189       }
   4190     } else {
   4191       __ Move(ebx, ToRegister(key));
   4192       __ SmiTag(ebx);
   4193     }
   4194 
   4195     GrowArrayElementsStub stub(isolate(), instr->hydrogen()->kind());
   4196     __ CallStub(&stub);
   4197     RecordSafepointWithLazyDeopt(
   4198         instr, RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS);
   4199     __ StoreToSafepointRegisterSlot(result, result);
   4200   }
   4201 
   4202   // Deopt on smi, which means the elements array changed to dictionary mode.
   4203   __ test(result, Immediate(kSmiTagMask));
   4204   DeoptimizeIf(equal, instr, DeoptimizeReason::kSmi);
   4205 }
   4206 
   4207 
   4208 void LCodeGen::DoTransitionElementsKind(LTransitionElementsKind* instr) {
   4209   Register object_reg = ToRegister(instr->object());
   4210 
   4211   Handle<Map> from_map = instr->original_map();
   4212   Handle<Map> to_map = instr->transitioned_map();
   4213   ElementsKind from_kind = instr->from_kind();
   4214   ElementsKind to_kind = instr->to_kind();
   4215 
   4216   Label not_applicable;
   4217   bool is_simple_map_transition =
   4218       IsSimpleMapChangeTransition(from_kind, to_kind);
   4219   Label::Distance branch_distance =
   4220       is_simple_map_transition ? Label::kNear : Label::kFar;
   4221   __ cmp(FieldOperand(object_reg, HeapObject::kMapOffset), from_map);
   4222   __ j(not_equal, &not_applicable, branch_distance);
   4223   if (is_simple_map_transition) {
   4224     Register new_map_reg = ToRegister(instr->new_map_temp());
   4225     __ mov(FieldOperand(object_reg, HeapObject::kMapOffset),
   4226            Immediate(to_map));
   4227     // Write barrier.
   4228     DCHECK_NOT_NULL(instr->temp());
   4229     __ RecordWriteForMap(object_reg, to_map, new_map_reg,
   4230                          ToRegister(instr->temp()), kDontSaveFPRegs);
   4231   } else {
   4232     DCHECK(ToRegister(instr->context()).is(esi));
   4233     DCHECK(object_reg.is(eax));
   4234     PushSafepointRegistersScope scope(this);
   4235     __ mov(ebx, to_map);
   4236     TransitionElementsKindStub stub(isolate(), from_kind, to_kind);
   4237     __ CallStub(&stub);
   4238     RecordSafepointWithLazyDeopt(instr,
   4239         RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS);
   4240   }
   4241   __ bind(&not_applicable);
   4242 }
   4243 
   4244 
   4245 void LCodeGen::DoStringCharCodeAt(LStringCharCodeAt* instr) {
   4246   class DeferredStringCharCodeAt final : public LDeferredCode {
   4247    public:
   4248     DeferredStringCharCodeAt(LCodeGen* codegen,
   4249                              LStringCharCodeAt* instr,
   4250                              const X87Stack& x87_stack)
   4251         : LDeferredCode(codegen, x87_stack), instr_(instr) { }
   4252     void Generate() override { codegen()->DoDeferredStringCharCodeAt(instr_); }
   4253     LInstruction* instr() override { return instr_; }
   4254 
   4255    private:
   4256     LStringCharCodeAt* instr_;
   4257   };
   4258 
   4259   DeferredStringCharCodeAt* deferred =
   4260       new(zone()) DeferredStringCharCodeAt(this, instr, x87_stack_);
   4261 
   4262   StringCharLoadGenerator::Generate(masm(),
   4263                                     factory(),
   4264                                     ToRegister(instr->string()),
   4265                                     ToRegister(instr->index()),
   4266                                     ToRegister(instr->result()),
   4267                                     deferred->entry());
   4268   __ bind(deferred->exit());
   4269 }
   4270 
   4271 
   4272 void LCodeGen::DoDeferredStringCharCodeAt(LStringCharCodeAt* instr) {
   4273   Register string = ToRegister(instr->string());
   4274   Register result = ToRegister(instr->result());
   4275 
   4276   // TODO(3095996): Get rid of this. For now, we need to make the
   4277   // result register contain a valid pointer because it is already
   4278   // contained in the register pointer map.
   4279   __ Move(result, Immediate(0));
   4280 
   4281   PushSafepointRegistersScope scope(this);
   4282   __ push(string);
   4283   // Push the index as a smi. This is safe because of the checks in
   4284   // DoStringCharCodeAt above.
   4285   STATIC_ASSERT(String::kMaxLength <= Smi::kMaxValue);
   4286   if (instr->index()->IsConstantOperand()) {
   4287     Immediate immediate = ToImmediate(LConstantOperand::cast(instr->index()),
   4288                                       Representation::Smi());
   4289     __ push(immediate);
   4290   } else {
   4291     Register index = ToRegister(instr->index());
   4292     __ SmiTag(index);
   4293     __ push(index);
   4294   }
   4295   CallRuntimeFromDeferred(Runtime::kStringCharCodeAtRT, 2,
   4296                           instr, instr->context());
   4297   __ AssertSmi(eax);
   4298   __ SmiUntag(eax);
   4299   __ StoreToSafepointRegisterSlot(result, eax);
   4300 }
   4301 
   4302 
   4303 void LCodeGen::DoStringCharFromCode(LStringCharFromCode* instr) {
   4304   class DeferredStringCharFromCode final : public LDeferredCode {
   4305    public:
   4306     DeferredStringCharFromCode(LCodeGen* codegen,
   4307                                LStringCharFromCode* instr,
   4308                                const X87Stack& x87_stack)
   4309         : LDeferredCode(codegen, x87_stack), instr_(instr) { }
   4310     void Generate() override {
   4311       codegen()->DoDeferredStringCharFromCode(instr_);
   4312     }
   4313     LInstruction* instr() override { return instr_; }
   4314 
   4315    private:
   4316     LStringCharFromCode* instr_;
   4317   };
   4318 
   4319   DeferredStringCharFromCode* deferred =
   4320       new(zone()) DeferredStringCharFromCode(this, instr, x87_stack_);
   4321 
   4322   DCHECK(instr->hydrogen()->value()->representation().IsInteger32());
   4323   Register char_code = ToRegister(instr->char_code());
   4324   Register result = ToRegister(instr->result());
   4325   DCHECK(!char_code.is(result));
   4326 
   4327   __ cmp(char_code, String::kMaxOneByteCharCode);
   4328   __ j(above, deferred->entry());
   4329   __ Move(result, Immediate(factory()->single_character_string_cache()));
   4330   __ mov(result, FieldOperand(result,
   4331                               char_code, times_pointer_size,
   4332                               FixedArray::kHeaderSize));
   4333   __ cmp(result, factory()->undefined_value());
   4334   __ j(equal, deferred->entry());
   4335   __ bind(deferred->exit());
   4336 }
   4337 
   4338 
   4339 void LCodeGen::DoDeferredStringCharFromCode(LStringCharFromCode* instr) {
   4340   Register char_code = ToRegister(instr->char_code());
   4341   Register result = ToRegister(instr->result());
   4342 
   4343   // TODO(3095996): Get rid of this. For now, we need to make the
   4344   // result register contain a valid pointer because it is already
   4345   // contained in the register pointer map.
   4346   __ Move(result, Immediate(0));
   4347 
   4348   PushSafepointRegistersScope scope(this);
   4349   __ SmiTag(char_code);
   4350   __ push(char_code);
   4351   CallRuntimeFromDeferred(Runtime::kStringCharFromCode, 1, instr,
   4352                           instr->context());
   4353   __ StoreToSafepointRegisterSlot(result, eax);
   4354 }
   4355 
   4356 
   4357 void LCodeGen::DoStringAdd(LStringAdd* instr) {
   4358   DCHECK(ToRegister(instr->context()).is(esi));
   4359   DCHECK(ToRegister(instr->left()).is(edx));
   4360   DCHECK(ToRegister(instr->right()).is(eax));
   4361   StringAddStub stub(isolate(),
   4362                      instr->hydrogen()->flags(),
   4363                      instr->hydrogen()->pretenure_flag());
   4364   CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
   4365 }
   4366 
   4367 
   4368 void LCodeGen::DoInteger32ToDouble(LInteger32ToDouble* instr) {
   4369   LOperand* input = instr->value();
   4370   LOperand* output = instr->result();
   4371   DCHECK(input->IsRegister() || input->IsStackSlot());
   4372   DCHECK(output->IsDoubleRegister());
   4373   if (input->IsRegister()) {
   4374     Register input_reg = ToRegister(input);
   4375     __ push(input_reg);
   4376     X87Mov(ToX87Register(output), Operand(esp, 0), kX87IntOperand);
   4377     __ pop(input_reg);
   4378   } else {
   4379     X87Mov(ToX87Register(output), ToOperand(input), kX87IntOperand);
   4380   }
   4381 }
   4382 
   4383 
   4384 void LCodeGen::DoUint32ToDouble(LUint32ToDouble* instr) {
   4385   LOperand* input = instr->value();
   4386   LOperand* output = instr->result();
   4387   X87Register res = ToX87Register(output);
   4388   X87PrepareToWrite(res);
   4389   __ LoadUint32NoSSE2(ToRegister(input));
   4390   X87CommitWrite(res);
   4391 }
   4392 
   4393 
   4394 void LCodeGen::DoNumberTagI(LNumberTagI* instr) {
   4395   class DeferredNumberTagI final : public LDeferredCode {
   4396    public:
   4397     DeferredNumberTagI(LCodeGen* codegen,
   4398                        LNumberTagI* instr,
   4399                        const X87Stack& x87_stack)
   4400         : LDeferredCode(codegen, x87_stack), instr_(instr) { }
   4401     void Generate() override {
   4402       codegen()->DoDeferredNumberTagIU(instr_, instr_->value(), instr_->temp(),
   4403                                        SIGNED_INT32);
   4404     }
   4405     LInstruction* instr() override { return instr_; }
   4406 
   4407    private:
   4408     LNumberTagI* instr_;
   4409   };
   4410 
   4411   LOperand* input = instr->value();
   4412   DCHECK(input->IsRegister() && input->Equals(instr->result()));
   4413   Register reg = ToRegister(input);
   4414 
   4415   DeferredNumberTagI* deferred =
   4416       new(zone()) DeferredNumberTagI(this, instr, x87_stack_);
   4417   __ SmiTag(reg);
   4418   __ j(overflow, deferred->entry());
   4419   __ bind(deferred->exit());
   4420 }
   4421 
   4422 
   4423 void LCodeGen::DoNumberTagU(LNumberTagU* instr) {
   4424   class DeferredNumberTagU final : public LDeferredCode {
   4425    public:
   4426     DeferredNumberTagU(LCodeGen* codegen,
   4427                        LNumberTagU* instr,
   4428                        const X87Stack& x87_stack)
   4429         : LDeferredCode(codegen, x87_stack), instr_(instr) { }
   4430     void Generate() override {
   4431       codegen()->DoDeferredNumberTagIU(instr_, instr_->value(), instr_->temp(),
   4432                                        UNSIGNED_INT32);
   4433     }
   4434     LInstruction* instr() override { return instr_; }
   4435 
   4436    private:
   4437     LNumberTagU* instr_;
   4438   };
   4439 
   4440   LOperand* input = instr->value();
   4441   DCHECK(input->IsRegister() && input->Equals(instr->result()));
   4442   Register reg = ToRegister(input);
   4443 
   4444   DeferredNumberTagU* deferred =
   4445       new(zone()) DeferredNumberTagU(this, instr, x87_stack_);
   4446   __ cmp(reg, Immediate(Smi::kMaxValue));
   4447   __ j(above, deferred->entry());
   4448   __ SmiTag(reg);
   4449   __ bind(deferred->exit());
   4450 }
   4451 
   4452 
   4453 void LCodeGen::DoDeferredNumberTagIU(LInstruction* instr,
   4454                                      LOperand* value,
   4455                                      LOperand* temp,
   4456                                      IntegerSignedness signedness) {
   4457   Label done, slow;
   4458   Register reg = ToRegister(value);
   4459   Register tmp = ToRegister(temp);
   4460 
   4461   if (signedness == SIGNED_INT32) {
   4462     // There was overflow, so bits 30 and 31 of the original integer
   4463     // disagree. Try to allocate a heap number in new space and store
   4464     // the value in there. If that fails, call the runtime system.
   4465     __ SmiUntag(reg);
   4466     __ xor_(reg, 0x80000000);
   4467     __ push(reg);
   4468     __ fild_s(Operand(esp, 0));
   4469     __ pop(reg);
   4470   } else {
   4471     // There's no fild variant for unsigned values, so zero-extend to a 64-bit
   4472     // int manually.
   4473     __ push(Immediate(0));
   4474     __ push(reg);
   4475     __ fild_d(Operand(esp, 0));
   4476     __ pop(reg);
   4477     __ pop(reg);
   4478   }
   4479 
   4480   if (FLAG_inline_new) {
   4481     __ AllocateHeapNumber(reg, tmp, no_reg, &slow);
   4482     __ jmp(&done, Label::kNear);
   4483   }
   4484 
   4485   // Slow case: Call the runtime system to do the number allocation.
   4486   __ bind(&slow);
   4487   {
   4488     // TODO(3095996): Put a valid pointer value in the stack slot where the
   4489     // result register is stored, as this register is in the pointer map, but
   4490     // contains an integer value.
   4491     __ Move(reg, Immediate(0));
   4492 
   4493     // Preserve the value of all registers.
   4494     PushSafepointRegistersScope scope(this);
   4495     // Reset the context register.
   4496     if (!reg.is(esi)) {
   4497       __ Move(esi, Immediate(0));
   4498     }
   4499     __ CallRuntimeSaveDoubles(Runtime::kAllocateHeapNumber);
   4500     RecordSafepointWithRegisters(
   4501         instr->pointer_map(), 0, Safepoint::kNoLazyDeopt);
   4502     __ StoreToSafepointRegisterSlot(reg, eax);
   4503   }
   4504 
   4505   __ bind(&done);
   4506   __ fstp_d(FieldOperand(reg, HeapNumber::kValueOffset));
   4507 }
   4508 
   4509 
   4510 void LCodeGen::DoNumberTagD(LNumberTagD* instr) {
   4511   class DeferredNumberTagD final : public LDeferredCode {
   4512    public:
   4513     DeferredNumberTagD(LCodeGen* codegen,
   4514                        LNumberTagD* instr,
   4515                        const X87Stack& x87_stack)
   4516         : LDeferredCode(codegen, x87_stack), instr_(instr) { }
   4517     void Generate() override { codegen()->DoDeferredNumberTagD(instr_); }
   4518     LInstruction* instr() override { return instr_; }
   4519 
   4520    private:
   4521     LNumberTagD* instr_;
   4522   };
   4523 
   4524   Register reg = ToRegister(instr->result());
   4525 
   4526   // Put the value to the top of stack
   4527   X87Register src = ToX87Register(instr->value());
   4528   // Don't use X87LoadForUsage here, which is only used by Instruction which
   4529   // clobbers fp registers.
   4530   x87_stack_.Fxch(src);
   4531 
   4532   DeferredNumberTagD* deferred =
   4533       new(zone()) DeferredNumberTagD(this, instr, x87_stack_);
   4534   if (FLAG_inline_new) {
   4535     Register tmp = ToRegister(instr->temp());
   4536     __ AllocateHeapNumber(reg, tmp, no_reg, deferred->entry());
   4537   } else {
   4538     __ jmp(deferred->entry());
   4539   }
   4540   __ bind(deferred->exit());
   4541   __ fst_d(FieldOperand(reg, HeapNumber::kValueOffset));
   4542 }
   4543 
   4544 
   4545 void LCodeGen::DoDeferredNumberTagD(LNumberTagD* instr) {
   4546   // TODO(3095996): Get rid of this. For now, we need to make the
   4547   // result register contain a valid pointer because it is already
   4548   // contained in the register pointer map.
   4549   Register reg = ToRegister(instr->result());
   4550   __ Move(reg, Immediate(0));
   4551 
   4552   PushSafepointRegistersScope scope(this);
   4553   // Reset the context register.
   4554   if (!reg.is(esi)) {
   4555     __ Move(esi, Immediate(0));
   4556   }
   4557   __ CallRuntimeSaveDoubles(Runtime::kAllocateHeapNumber);
   4558   RecordSafepointWithRegisters(
   4559       instr->pointer_map(), 0, Safepoint::kNoLazyDeopt);
   4560   __ StoreToSafepointRegisterSlot(reg, eax);
   4561 }
   4562 
   4563 
   4564 void LCodeGen::DoSmiTag(LSmiTag* instr) {
   4565   HChange* hchange = instr->hydrogen();
   4566   Register input = ToRegister(instr->value());
   4567   if (hchange->CheckFlag(HValue::kCanOverflow) &&
   4568       hchange->value()->CheckFlag(HValue::kUint32)) {
   4569     __ test(input, Immediate(0xc0000000));
   4570     DeoptimizeIf(not_zero, instr, DeoptimizeReason::kOverflow);
   4571   }
   4572   __ SmiTag(input);
   4573   if (hchange->CheckFlag(HValue::kCanOverflow) &&
   4574       !hchange->value()->CheckFlag(HValue::kUint32)) {
   4575     DeoptimizeIf(overflow, instr, DeoptimizeReason::kOverflow);
   4576   }
   4577 }
   4578 
   4579 
   4580 void LCodeGen::DoSmiUntag(LSmiUntag* instr) {
   4581   LOperand* input = instr->value();
   4582   Register result = ToRegister(input);
   4583   DCHECK(input->IsRegister() && input->Equals(instr->result()));
   4584   if (instr->needs_check()) {
   4585     __ test(result, Immediate(kSmiTagMask));
   4586     DeoptimizeIf(not_zero, instr, DeoptimizeReason::kNotASmi);
   4587   } else {
   4588     __ AssertSmi(result);
   4589   }
   4590   __ SmiUntag(result);
   4591 }
   4592 
   4593 
   4594 void LCodeGen::EmitNumberUntagDNoSSE2(LNumberUntagD* instr, Register input_reg,
   4595                                       Register temp_reg, X87Register res_reg,
   4596                                       NumberUntagDMode mode) {
   4597   bool can_convert_undefined_to_nan = instr->truncating();
   4598   bool deoptimize_on_minus_zero = instr->hydrogen()->deoptimize_on_minus_zero();
   4599 
   4600   Label load_smi, done;
   4601 
   4602   X87PrepareToWrite(res_reg);
   4603   if (mode == NUMBER_CANDIDATE_IS_ANY_TAGGED) {
   4604     // Smi check.
   4605     __ JumpIfSmi(input_reg, &load_smi);
   4606 
   4607     // Heap number map check.
   4608     __ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
   4609            factory()->heap_number_map());
   4610     if (!can_convert_undefined_to_nan) {
   4611       DeoptimizeIf(not_equal, instr, DeoptimizeReason::kNotAHeapNumber);
   4612     } else {
   4613       Label heap_number, convert;
   4614       __ j(equal, &heap_number);
   4615 
   4616       // Convert undefined (or hole) to NaN.
   4617       __ cmp(input_reg, factory()->undefined_value());
   4618       DeoptimizeIf(not_equal, instr,
   4619                    DeoptimizeReason::kNotAHeapNumberUndefined);
   4620 
   4621       __ bind(&convert);
   4622       __ push(Immediate(0xfff80000));
   4623       __ push(Immediate(0x00000000));
   4624       __ fld_d(MemOperand(esp, 0));
   4625       __ lea(esp, Operand(esp, kDoubleSize));
   4626       __ jmp(&done, Label::kNear);
   4627 
   4628       __ bind(&heap_number);
   4629     }
   4630     // Heap number to x87 conversion.
   4631     __ fld_d(FieldOperand(input_reg, HeapNumber::kValueOffset));
   4632     if (deoptimize_on_minus_zero) {
   4633       __ fldz();
   4634       __ FCmp();
   4635       __ fld_d(FieldOperand(input_reg, HeapNumber::kValueOffset));
   4636       __ j(not_zero, &done, Label::kNear);
   4637 
   4638       // Use general purpose registers to check if we have -0.0
   4639       __ mov(temp_reg, FieldOperand(input_reg, HeapNumber::kExponentOffset));
   4640       __ test(temp_reg, Immediate(HeapNumber::kSignMask));
   4641       __ j(zero, &done, Label::kNear);
   4642 
   4643       // Pop FPU stack before deoptimizing.
   4644       __ fstp(0);
   4645       DeoptimizeIf(not_zero, instr, DeoptimizeReason::kMinusZero);
   4646     }
   4647     __ jmp(&done, Label::kNear);
   4648   } else {
   4649     DCHECK(mode == NUMBER_CANDIDATE_IS_SMI);
   4650   }
   4651 
   4652   __ bind(&load_smi);
   4653   // Clobbering a temp is faster than re-tagging the
   4654   // input register since we avoid dependencies.
   4655   __ mov(temp_reg, input_reg);
   4656   __ SmiUntag(temp_reg);  // Untag smi before converting to float.
   4657   __ push(temp_reg);
   4658   __ fild_s(Operand(esp, 0));
   4659   __ add(esp, Immediate(kPointerSize));
   4660   __ bind(&done);
   4661   X87CommitWrite(res_reg);
   4662 }
   4663 
   4664 
   4665 void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr, Label* done) {
   4666   Register input_reg = ToRegister(instr->value());
   4667 
   4668   // The input was optimistically untagged; revert it.
   4669   STATIC_ASSERT(kSmiTagSize == 1);
   4670   __ lea(input_reg, Operand(input_reg, times_2, kHeapObjectTag));
   4671 
   4672   if (instr->truncating()) {
   4673     Label truncate;
   4674     Label::Distance truncate_distance =
   4675         DeoptEveryNTimes() ? Label::kFar : Label::kNear;
   4676     __ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
   4677            factory()->heap_number_map());
   4678     __ j(equal, &truncate, truncate_distance);
   4679     __ push(input_reg);
   4680     __ CmpObjectType(input_reg, ODDBALL_TYPE, input_reg);
   4681     __ pop(input_reg);
   4682     DeoptimizeIf(not_equal, instr, DeoptimizeReason::kNotANumberOrOddball);
   4683     __ bind(&truncate);
   4684     __ TruncateHeapNumberToI(input_reg, input_reg);
   4685   } else {
   4686     // TODO(olivf) Converting a number on the fpu is actually quite slow. We
   4687     // should first try a fast conversion and then bailout to this slow case.
   4688     __ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
   4689            isolate()->factory()->heap_number_map());
   4690     DeoptimizeIf(not_equal, instr, DeoptimizeReason::kNotAHeapNumber);
   4691 
   4692     __ sub(esp, Immediate(kPointerSize));
   4693     __ fld_d(FieldOperand(input_reg, HeapNumber::kValueOffset));
   4694 
   4695     if (instr->hydrogen()->GetMinusZeroMode() == FAIL_ON_MINUS_ZERO) {
   4696       Label no_precision_lost, not_nan, zero_check;
   4697       __ fld(0);
   4698 
   4699       __ fist_s(MemOperand(esp, 0));
   4700       __ fild_s(MemOperand(esp, 0));
   4701       __ FCmp();
   4702       __ pop(input_reg);
   4703 
   4704       __ j(equal, &no_precision_lost, Label::kNear);
   4705       __ fstp(0);
   4706       DeoptimizeIf(no_condition, instr, DeoptimizeReason::kLostPrecision);
   4707       __ bind(&no_precision_lost);
   4708 
   4709       __ j(parity_odd, &not_nan);
   4710       __ fstp(0);
   4711       DeoptimizeIf(no_condition, instr, DeoptimizeReason::kNaN);
   4712       __ bind(&not_nan);
   4713 
   4714       __ test(input_reg, Operand(input_reg));
   4715       __ j(zero, &zero_check, Label::kNear);
   4716       __ fstp(0);
   4717       __ jmp(done);
   4718 
   4719       __ bind(&zero_check);
   4720       // To check for minus zero, we load the value again as float, and check
   4721       // if that is still 0.
   4722       __ sub(esp, Immediate(kPointerSize));
   4723       __ fstp_s(Operand(esp, 0));
   4724       __ pop(input_reg);
   4725       __ test(input_reg, Operand(input_reg));
   4726       DeoptimizeIf(not_zero, instr, DeoptimizeReason::kMinusZero);
   4727     } else {
   4728       __ fist_s(MemOperand(esp, 0));
   4729       __ fild_s(MemOperand(esp, 0));
   4730       __ FCmp();
   4731       __ pop(input_reg);
   4732       DeoptimizeIf(not_equal, instr, DeoptimizeReason::kLostPrecision);
   4733       DeoptimizeIf(parity_even, instr, DeoptimizeReason::kNaN);
   4734     }
   4735   }
   4736 }
   4737 
   4738 
   4739 void LCodeGen::DoTaggedToI(LTaggedToI* instr) {
   4740   class DeferredTaggedToI final : public LDeferredCode {
   4741    public:
   4742     DeferredTaggedToI(LCodeGen* codegen,
   4743                       LTaggedToI* instr,
   4744                       const X87Stack& x87_stack)
   4745         : LDeferredCode(codegen, x87_stack), instr_(instr) { }
   4746     void Generate() override { codegen()->DoDeferredTaggedToI(instr_, done()); }
   4747     LInstruction* instr() override { return instr_; }
   4748 
   4749    private:
   4750     LTaggedToI* instr_;
   4751   };
   4752 
   4753   LOperand* input = instr->value();
   4754   DCHECK(input->IsRegister());
   4755   Register input_reg = ToRegister(input);
   4756   DCHECK(input_reg.is(ToRegister(instr->result())));
   4757 
   4758   if (instr->hydrogen()->value()->representation().IsSmi()) {
   4759     __ SmiUntag(input_reg);
   4760   } else {
   4761     DeferredTaggedToI* deferred =
   4762         new(zone()) DeferredTaggedToI(this, instr, x87_stack_);
   4763     // Optimistically untag the input.
   4764     // If the input is a HeapObject, SmiUntag will set the carry flag.
   4765     STATIC_ASSERT(kSmiTagSize == 1 && kSmiTag == 0);
   4766     __ SmiUntag(input_reg);
   4767     // Branch to deferred code if the input was tagged.
   4768     // The deferred code will take care of restoring the tag.
   4769     __ j(carry, deferred->entry());
   4770     __ bind(deferred->exit());
   4771   }
   4772 }
   4773 
   4774 
   4775 void LCodeGen::DoNumberUntagD(LNumberUntagD* instr) {
   4776   LOperand* input = instr->value();
   4777   DCHECK(input->IsRegister());
   4778   LOperand* temp = instr->temp();
   4779   DCHECK(temp->IsRegister());
   4780   LOperand* result = instr->result();
   4781   DCHECK(result->IsDoubleRegister());
   4782 
   4783   Register input_reg = ToRegister(input);
   4784   Register temp_reg = ToRegister(temp);
   4785 
   4786   HValue* value = instr->hydrogen()->value();
   4787   NumberUntagDMode mode = value->representation().IsSmi()
   4788       ? NUMBER_CANDIDATE_IS_SMI : NUMBER_CANDIDATE_IS_ANY_TAGGED;
   4789 
   4790   EmitNumberUntagDNoSSE2(instr, input_reg, temp_reg, ToX87Register(result),
   4791                          mode);
   4792 }
   4793 
   4794 
   4795 void LCodeGen::DoDoubleToI(LDoubleToI* instr) {
   4796   LOperand* input = instr->value();
   4797   DCHECK(input->IsDoubleRegister());
   4798   LOperand* result = instr->result();
   4799   DCHECK(result->IsRegister());
   4800   Register result_reg = ToRegister(result);
   4801 
   4802   if (instr->truncating()) {
   4803     X87Register input_reg = ToX87Register(input);
   4804     X87Fxch(input_reg);
   4805     __ TruncateX87TOSToI(result_reg);
   4806   } else {
   4807     Label lost_precision, is_nan, minus_zero, done;
   4808     X87Register input_reg = ToX87Register(input);
   4809     X87Fxch(input_reg);
   4810     __ X87TOSToI(result_reg, instr->hydrogen()->GetMinusZeroMode(),
   4811                  &lost_precision, &is_nan, &minus_zero);
   4812     __ jmp(&done);
   4813     __ bind(&lost_precision);
   4814     DeoptimizeIf(no_condition, instr, DeoptimizeReason::kLostPrecision);
   4815     __ bind(&is_nan);
   4816     DeoptimizeIf(no_condition, instr, DeoptimizeReason::kNaN);
   4817     __ bind(&minus_zero);
   4818     DeoptimizeIf(no_condition, instr, DeoptimizeReason::kMinusZero);
   4819     __ bind(&done);
   4820   }
   4821 }
   4822 
   4823 
   4824 void LCodeGen::DoDoubleToSmi(LDoubleToSmi* instr) {
   4825   LOperand* input = instr->value();
   4826   DCHECK(input->IsDoubleRegister());
   4827   LOperand* result = instr->result();
   4828   DCHECK(result->IsRegister());
   4829   Register result_reg = ToRegister(result);
   4830 
   4831   Label lost_precision, is_nan, minus_zero, done;
   4832   X87Register input_reg = ToX87Register(input);
   4833   X87Fxch(input_reg);
   4834   __ X87TOSToI(result_reg, instr->hydrogen()->GetMinusZeroMode(),
   4835                &lost_precision, &is_nan, &minus_zero);
   4836   __ jmp(&done);
   4837   __ bind(&lost_precision);
   4838   DeoptimizeIf(no_condition, instr, DeoptimizeReason::kLostPrecision);
   4839   __ bind(&is_nan);
   4840   DeoptimizeIf(no_condition, instr, DeoptimizeReason::kNaN);
   4841   __ bind(&minus_zero);
   4842   DeoptimizeIf(no_condition, instr, DeoptimizeReason::kMinusZero);
   4843   __ bind(&done);
   4844   __ SmiTag(result_reg);
   4845   DeoptimizeIf(overflow, instr, DeoptimizeReason::kOverflow);
   4846 }
   4847 
   4848 
   4849 void LCodeGen::DoCheckSmi(LCheckSmi* instr) {
   4850   LOperand* input = instr->value();
   4851   __ test(ToOperand(input), Immediate(kSmiTagMask));
   4852   DeoptimizeIf(not_zero, instr, DeoptimizeReason::kNotASmi);
   4853 }
   4854 
   4855 
   4856 void LCodeGen::DoCheckNonSmi(LCheckNonSmi* instr) {
   4857   if (!instr->hydrogen()->value()->type().IsHeapObject()) {
   4858     LOperand* input = instr->value();
   4859     __ test(ToOperand(input), Immediate(kSmiTagMask));
   4860     DeoptimizeIf(zero, instr, DeoptimizeReason::kSmi);
   4861   }
   4862 }
   4863 
   4864 
   4865 void LCodeGen::DoCheckArrayBufferNotNeutered(
   4866     LCheckArrayBufferNotNeutered* instr) {
   4867   Register view = ToRegister(instr->view());
   4868   Register scratch = ToRegister(instr->scratch());
   4869 
   4870   __ mov(scratch, FieldOperand(view, JSArrayBufferView::kBufferOffset));
   4871   __ test_b(FieldOperand(scratch, JSArrayBuffer::kBitFieldOffset),
   4872             Immediate(1 << JSArrayBuffer::WasNeutered::kShift));
   4873   DeoptimizeIf(not_zero, instr, DeoptimizeReason::kOutOfBounds);
   4874 }
   4875 
   4876 
   4877 void LCodeGen::DoCheckInstanceType(LCheckInstanceType* instr) {
   4878   Register input = ToRegister(instr->value());
   4879   Register temp = ToRegister(instr->temp());
   4880 
   4881   __ mov(temp, FieldOperand(input, HeapObject::kMapOffset));
   4882 
   4883   if (instr->hydrogen()->is_interval_check()) {
   4884     InstanceType first;
   4885     InstanceType last;
   4886     instr->hydrogen()->GetCheckInterval(&first, &last);
   4887 
   4888     __ cmpb(FieldOperand(temp, Map::kInstanceTypeOffset), Immediate(first));
   4889 
   4890     // If there is only one type in the interval check for equality.
   4891     if (first == last) {
   4892       DeoptimizeIf(not_equal, instr, DeoptimizeReason::kWrongInstanceType);
   4893     } else {
   4894       DeoptimizeIf(below, instr, DeoptimizeReason::kWrongInstanceType);
   4895       // Omit check for the last type.
   4896       if (last != LAST_TYPE) {
   4897         __ cmpb(FieldOperand(temp, Map::kInstanceTypeOffset), Immediate(last));
   4898         DeoptimizeIf(above, instr, DeoptimizeReason::kWrongInstanceType);
   4899       }
   4900     }
   4901   } else {
   4902     uint8_t mask;
   4903     uint8_t tag;
   4904     instr->hydrogen()->GetCheckMaskAndTag(&mask, &tag);
   4905 
   4906     if (base::bits::IsPowerOfTwo32(mask)) {
   4907       DCHECK(tag == 0 || base::bits::IsPowerOfTwo32(tag));
   4908       __ test_b(FieldOperand(temp, Map::kInstanceTypeOffset), Immediate(mask));
   4909       DeoptimizeIf(tag == 0 ? not_zero : zero, instr,
   4910                    DeoptimizeReason::kWrongInstanceType);
   4911     } else {
   4912       __ movzx_b(temp, FieldOperand(temp, Map::kInstanceTypeOffset));
   4913       __ and_(temp, mask);
   4914       __ cmp(temp, tag);
   4915       DeoptimizeIf(not_equal, instr, DeoptimizeReason::kWrongInstanceType);
   4916     }
   4917   }
   4918 }
   4919 
   4920 
   4921 void LCodeGen::DoCheckValue(LCheckValue* instr) {
   4922   Handle<HeapObject> object = instr->hydrogen()->object().handle();
   4923   if (instr->hydrogen()->object_in_new_space()) {
   4924     Register reg = ToRegister(instr->value());
   4925     Handle<Cell> cell = isolate()->factory()->NewCell(object);
   4926     __ cmp(reg, Operand::ForCell(cell));
   4927   } else {
   4928     Operand operand = ToOperand(instr->value());
   4929     __ cmp(operand, object);
   4930   }
   4931   DeoptimizeIf(not_equal, instr, DeoptimizeReason::kValueMismatch);
   4932 }
   4933 
   4934 
   4935 void LCodeGen::DoDeferredInstanceMigration(LCheckMaps* instr, Register object) {
   4936   {
   4937     PushSafepointRegistersScope scope(this);
   4938     __ push(object);
   4939     __ xor_(esi, esi);
   4940     __ CallRuntimeSaveDoubles(Runtime::kTryMigrateInstance);
   4941     RecordSafepointWithRegisters(
   4942         instr->pointer_map(), 1, Safepoint::kNoLazyDeopt);
   4943 
   4944     __ test(eax, Immediate(kSmiTagMask));
   4945   }
   4946   DeoptimizeIf(zero, instr, DeoptimizeReason::kInstanceMigrationFailed);
   4947 }
   4948 
   4949 
   4950 void LCodeGen::DoCheckMaps(LCheckMaps* instr) {
   4951   class DeferredCheckMaps final : public LDeferredCode {
   4952    public:
   4953     DeferredCheckMaps(LCodeGen* codegen,
   4954                       LCheckMaps* instr,
   4955                       Register object,
   4956                       const X87Stack& x87_stack)
   4957         : LDeferredCode(codegen, x87_stack), instr_(instr), object_(object) {
   4958       SetExit(check_maps());
   4959     }
   4960     void Generate() override {
   4961       codegen()->DoDeferredInstanceMigration(instr_, object_);
   4962     }
   4963     Label* check_maps() { return &check_maps_; }
   4964     LInstruction* instr() override { return instr_; }
   4965 
   4966    private:
   4967     LCheckMaps* instr_;
   4968     Label check_maps_;
   4969     Register object_;
   4970   };
   4971 
   4972   if (instr->hydrogen()->IsStabilityCheck()) {
   4973     const UniqueSet<Map>* maps = instr->hydrogen()->maps();
   4974     for (int i = 0; i < maps->size(); ++i) {
   4975       AddStabilityDependency(maps->at(i).handle());
   4976     }
   4977     return;
   4978   }
   4979 
   4980   LOperand* input = instr->value();
   4981   DCHECK(input->IsRegister());
   4982   Register reg = ToRegister(input);
   4983 
   4984   DeferredCheckMaps* deferred = NULL;
   4985   if (instr->hydrogen()->HasMigrationTarget()) {
   4986     deferred = new(zone()) DeferredCheckMaps(this, instr, reg, x87_stack_);
   4987     __ bind(deferred->check_maps());
   4988   }
   4989 
   4990   const UniqueSet<Map>* maps = instr->hydrogen()->maps();
   4991   Label success;
   4992   for (int i = 0; i < maps->size() - 1; i++) {
   4993     Handle<Map> map = maps->at(i).handle();
   4994     __ CompareMap(reg, map);
   4995     __ j(equal, &success, Label::kNear);
   4996   }
   4997 
   4998   Handle<Map> map = maps->at(maps->size() - 1).handle();
   4999   __ CompareMap(reg, map);
   5000   if (instr->hydrogen()->HasMigrationTarget()) {
   5001     __ j(not_equal, deferred->entry());
   5002   } else {
   5003     DeoptimizeIf(not_equal, instr, DeoptimizeReason::kWrongMap);
   5004   }
   5005 
   5006   __ bind(&success);
   5007 }
   5008 
   5009 
   5010 void LCodeGen::DoClampDToUint8(LClampDToUint8* instr) {
   5011   X87Register value_reg = ToX87Register(instr->unclamped());
   5012   Register result_reg = ToRegister(instr->result());
   5013   X87Fxch(value_reg);
   5014   __ ClampTOSToUint8(result_reg);
   5015 }
   5016 
   5017 
   5018 void LCodeGen::DoClampIToUint8(LClampIToUint8* instr) {
   5019   DCHECK(instr->unclamped()->Equals(instr->result()));
   5020   Register value_reg = ToRegister(instr->result());
   5021   __ ClampUint8(value_reg);
   5022 }
   5023 
   5024 
   5025 void LCodeGen::DoClampTToUint8NoSSE2(LClampTToUint8NoSSE2* instr) {
   5026   Register input_reg = ToRegister(instr->unclamped());
   5027   Register result_reg = ToRegister(instr->result());
   5028   Register scratch = ToRegister(instr->scratch());
   5029   Register scratch2 = ToRegister(instr->scratch2());
   5030   Register scratch3 = ToRegister(instr->scratch3());
   5031   Label is_smi, done, heap_number, valid_exponent,
   5032       largest_value, zero_result, maybe_nan_or_infinity;
   5033 
   5034   __ JumpIfSmi(input_reg, &is_smi);
   5035 
   5036   // Check for heap number
   5037   __ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
   5038          factory()->heap_number_map());
   5039   __ j(equal, &heap_number, Label::kNear);
   5040 
   5041   // Check for undefined. Undefined is converted to zero for clamping
   5042   // conversions.
   5043   __ cmp(input_reg, factory()->undefined_value());
   5044   DeoptimizeIf(not_equal, instr, DeoptimizeReason::kNotAHeapNumberUndefined);
   5045   __ jmp(&zero_result, Label::kNear);
   5046 
   5047   // Heap number
   5048   __ bind(&heap_number);
   5049 
   5050   // Surprisingly, all of the hand-crafted bit-manipulations below are much
   5051   // faster than the x86 FPU built-in instruction, especially since "banker's
   5052   // rounding" would be additionally very expensive
   5053 
   5054   // Get exponent word.
   5055   __ mov(scratch, FieldOperand(input_reg, HeapNumber::kExponentOffset));
   5056   __ mov(scratch3, FieldOperand(input_reg, HeapNumber::kMantissaOffset));
   5057 
   5058   // Test for negative values --> clamp to zero
   5059   __ test(scratch, scratch);
   5060   __ j(negative, &zero_result, Label::kNear);
   5061 
   5062   // Get exponent alone in scratch2.
   5063   __ mov(scratch2, scratch);
   5064   __ and_(scratch2, HeapNumber::kExponentMask);
   5065   __ shr(scratch2, HeapNumber::kExponentShift);
   5066   __ j(zero, &zero_result, Label::kNear);
   5067   __ sub(scratch2, Immediate(HeapNumber::kExponentBias - 1));
   5068   __ j(negative, &zero_result, Label::kNear);
   5069 
   5070   const uint32_t non_int8_exponent = 7;
   5071   __ cmp(scratch2, Immediate(non_int8_exponent + 1));
   5072   // If the exponent is too big, check for special values.
   5073   __ j(greater, &maybe_nan_or_infinity, Label::kNear);
   5074 
   5075   __ bind(&valid_exponent);
   5076   // Exponent word in scratch, exponent in scratch2. We know that 0 <= exponent
   5077   // < 7. The shift bias is the number of bits to shift the mantissa such that
   5078   // with an exponent of 7 such the that top-most one is in bit 30, allowing
   5079   // detection the rounding overflow of a 255.5 to 256 (bit 31 goes from 0 to
   5080   // 1).
   5081   int shift_bias = (30 - HeapNumber::kExponentShift) - 7 - 1;
   5082   __ lea(result_reg, MemOperand(scratch2, shift_bias));
   5083   // Here result_reg (ecx) is the shift, scratch is the exponent word.  Get the
   5084   // top bits of the mantissa.
   5085   __ and_(scratch, HeapNumber::kMantissaMask);
   5086   // Put back the implicit 1 of the mantissa
   5087   __ or_(scratch, 1 << HeapNumber::kExponentShift);
   5088   // Shift up to round
   5089   __ shl_cl(scratch);
   5090   // Use "banker's rounding" to spec: If fractional part of number is 0.5, then
   5091   // use the bit in the "ones" place and add it to the "halves" place, which has
   5092   // the effect of rounding to even.
   5093   __ mov(scratch2, scratch);
   5094   const uint32_t one_half_bit_shift = 30 - sizeof(uint8_t) * 8;
   5095   const uint32_t one_bit_shift = one_half_bit_shift + 1;
   5096   __ and_(scratch2, Immediate((1 << one_bit_shift) - 1));
   5097   __ cmp(scratch2, Immediate(1 << one_half_bit_shift));
   5098   Label no_round;
   5099   __ j(less, &no_round, Label::kNear);
   5100   Label round_up;
   5101   __ mov(scratch2, Immediate(1 << one_half_bit_shift));
   5102   __ j(greater, &round_up, Label::kNear);
   5103   __ test(scratch3, scratch3);
   5104   __ j(not_zero, &round_up, Label::kNear);
   5105   __ mov(scratch2, scratch);
   5106   __ and_(scratch2, Immediate(1 << one_bit_shift));
   5107   __ shr(scratch2, 1);
   5108   __ bind(&round_up);
   5109   __ add(scratch, scratch2);
   5110   __ j(overflow, &largest_value, Label::kNear);
   5111   __ bind(&no_round);
   5112   __ shr(scratch, 23);
   5113   __ mov(result_reg, scratch);
   5114   __ jmp(&done, Label::kNear);
   5115 
   5116   __ bind(&maybe_nan_or_infinity);
   5117   // Check for NaN/Infinity, all other values map to 255
   5118   __ cmp(scratch2, Immediate(HeapNumber::kInfinityOrNanExponent + 1));
   5119   __ j(not_equal, &largest_value, Label::kNear);
   5120 
   5121   // Check for NaN, which differs from Infinity in that at least one mantissa
   5122   // bit is set.
   5123   __ and_(scratch, HeapNumber::kMantissaMask);
   5124   __ or_(scratch, FieldOperand(input_reg, HeapNumber::kMantissaOffset));
   5125   __ j(not_zero, &zero_result, Label::kNear);  // M!=0 --> NaN
   5126   // Infinity -> Fall through to map to 255.
   5127 
   5128   __ bind(&largest_value);
   5129   __ mov(result_reg, Immediate(255));
   5130   __ jmp(&done, Label::kNear);
   5131 
   5132   __ bind(&zero_result);
   5133   __ xor_(result_reg, result_reg);
   5134   __ jmp(&done, Label::kNear);
   5135 
   5136   // smi
   5137   __ bind(&is_smi);
   5138   if (!input_reg.is(result_reg)) {
   5139     __ mov(result_reg, input_reg);
   5140   }
   5141   __ SmiUntag(result_reg);
   5142   __ ClampUint8(result_reg);
   5143   __ bind(&done);
   5144 }
   5145 
   5146 
   5147 void LCodeGen::DoAllocate(LAllocate* instr) {
   5148   class DeferredAllocate final : public LDeferredCode {
   5149    public:
   5150     DeferredAllocate(LCodeGen* codegen,
   5151                      LAllocate* instr,
   5152                      const X87Stack& x87_stack)
   5153         : LDeferredCode(codegen, x87_stack), instr_(instr) { }
   5154     void Generate() override { codegen()->DoDeferredAllocate(instr_); }
   5155     LInstruction* instr() override { return instr_; }
   5156 
   5157    private:
   5158     LAllocate* instr_;
   5159   };
   5160 
   5161   DeferredAllocate* deferred =
   5162       new(zone()) DeferredAllocate(this, instr, x87_stack_);
   5163 
   5164   Register result = ToRegister(instr->result());
   5165   Register temp = ToRegister(instr->temp());
   5166 
   5167   // Allocate memory for the object.
   5168   AllocationFlags flags = NO_ALLOCATION_FLAGS;
   5169   if (instr->hydrogen()->MustAllocateDoubleAligned()) {
   5170     flags = static_cast<AllocationFlags>(flags | DOUBLE_ALIGNMENT);
   5171   }
   5172   if (instr->hydrogen()->IsOldSpaceAllocation()) {
   5173     DCHECK(!instr->hydrogen()->IsNewSpaceAllocation());
   5174     flags = static_cast<AllocationFlags>(flags | PRETENURE);
   5175   }
   5176 
   5177   if (instr->hydrogen()->IsAllocationFoldingDominator()) {
   5178     flags = static_cast<AllocationFlags>(flags | ALLOCATION_FOLDING_DOMINATOR);
   5179   }
   5180   DCHECK(!instr->hydrogen()->IsAllocationFolded());
   5181 
   5182   if (instr->size()->IsConstantOperand()) {
   5183     int32_t size = ToInteger32(LConstantOperand::cast(instr->size()));
   5184     CHECK(size <= kMaxRegularHeapObjectSize);
   5185     __ Allocate(size, result, temp, no_reg, deferred->entry(), flags);
   5186   } else {
   5187     Register size = ToRegister(instr->size());
   5188     __ Allocate(size, result, temp, no_reg, deferred->entry(), flags);
   5189   }
   5190 
   5191   __ bind(deferred->exit());
   5192 
   5193   if (instr->hydrogen()->MustPrefillWithFiller()) {
   5194     if (instr->size()->IsConstantOperand()) {
   5195       int32_t size = ToInteger32(LConstantOperand::cast(instr->size()));
   5196       __ mov(temp, (size / kPointerSize) - 1);
   5197     } else {
   5198       temp = ToRegister(instr->size());
   5199       __ shr(temp, kPointerSizeLog2);
   5200       __ dec(temp);
   5201     }
   5202     Label loop;
   5203     __ bind(&loop);
   5204     __ mov(FieldOperand(result, temp, times_pointer_size, 0),
   5205         isolate()->factory()->one_pointer_filler_map());
   5206     __ dec(temp);
   5207     __ j(not_zero, &loop);
   5208   }
   5209 }
   5210 
   5211 void LCodeGen::DoFastAllocate(LFastAllocate* instr) {
   5212   DCHECK(instr->hydrogen()->IsAllocationFolded());
   5213   DCHECK(!instr->hydrogen()->IsAllocationFoldingDominator());
   5214   Register result = ToRegister(instr->result());
   5215   Register temp = ToRegister(instr->temp());
   5216 
   5217   AllocationFlags flags = ALLOCATION_FOLDED;
   5218   if (instr->hydrogen()->MustAllocateDoubleAligned()) {
   5219     flags = static_cast<AllocationFlags>(flags | DOUBLE_ALIGNMENT);
   5220   }
   5221   if (instr->hydrogen()->IsOldSpaceAllocation()) {
   5222     DCHECK(!instr->hydrogen()->IsNewSpaceAllocation());
   5223     flags = static_cast<AllocationFlags>(flags | PRETENURE);
   5224   }
   5225   if (instr->size()->IsConstantOperand()) {
   5226     int32_t size = ToInteger32(LConstantOperand::cast(instr->size()));
   5227     CHECK(size <= kMaxRegularHeapObjectSize);
   5228     __ FastAllocate(size, result, temp, flags);
   5229   } else {
   5230     Register size = ToRegister(instr->size());
   5231     __ FastAllocate(size, result, temp, flags);
   5232   }
   5233 }
   5234 
   5235 void LCodeGen::DoDeferredAllocate(LAllocate* instr) {
   5236   Register result = ToRegister(instr->result());
   5237 
   5238   // TODO(3095996): Get rid of this. For now, we need to make the
   5239   // result register contain a valid pointer because it is already
   5240   // contained in the register pointer map.
   5241   __ Move(result, Immediate(Smi::kZero));
   5242 
   5243   PushSafepointRegistersScope scope(this);
   5244   if (instr->size()->IsRegister()) {
   5245     Register size = ToRegister(instr->size());
   5246     DCHECK(!size.is(result));
   5247     __ SmiTag(ToRegister(instr->size()));
   5248     __ push(size);
   5249   } else {
   5250     int32_t size = ToInteger32(LConstantOperand::cast(instr->size()));
   5251     if (size >= 0 && size <= Smi::kMaxValue) {
   5252       __ push(Immediate(Smi::FromInt(size)));
   5253     } else {
   5254       // We should never get here at runtime => abort
   5255       __ int3();
   5256       return;
   5257     }
   5258   }
   5259 
   5260   int flags = AllocateDoubleAlignFlag::encode(
   5261       instr->hydrogen()->MustAllocateDoubleAligned());
   5262   if (instr->hydrogen()->IsOldSpaceAllocation()) {
   5263     DCHECK(!instr->hydrogen()->IsNewSpaceAllocation());
   5264     flags = AllocateTargetSpace::update(flags, OLD_SPACE);
   5265   } else {
   5266     flags = AllocateTargetSpace::update(flags, NEW_SPACE);
   5267   }
   5268   __ push(Immediate(Smi::FromInt(flags)));
   5269 
   5270   CallRuntimeFromDeferred(
   5271       Runtime::kAllocateInTargetSpace, 2, instr, instr->context());
   5272   __ StoreToSafepointRegisterSlot(result, eax);
   5273 
   5274   if (instr->hydrogen()->IsAllocationFoldingDominator()) {
   5275     AllocationFlags allocation_flags = NO_ALLOCATION_FLAGS;
   5276     if (instr->hydrogen()->IsOldSpaceAllocation()) {
   5277       DCHECK(!instr->hydrogen()->IsNewSpaceAllocation());
   5278       allocation_flags = static_cast<AllocationFlags>(flags | PRETENURE);
   5279     }
   5280     // If the allocation folding dominator allocate triggered a GC, allocation
   5281     // happend in the runtime. We have to reset the top pointer to virtually
   5282     // undo the allocation.
   5283     ExternalReference allocation_top =
   5284         AllocationUtils::GetAllocationTopReference(isolate(), allocation_flags);
   5285     __ sub(eax, Immediate(kHeapObjectTag));
   5286     __ mov(Operand::StaticVariable(allocation_top), eax);
   5287     __ add(eax, Immediate(kHeapObjectTag));
   5288   }
   5289 }
   5290 
   5291 
   5292 void LCodeGen::DoTypeof(LTypeof* instr) {
   5293   DCHECK(ToRegister(instr->context()).is(esi));
   5294   DCHECK(ToRegister(instr->value()).is(ebx));
   5295   Label end, do_call;
   5296   Register value_register = ToRegister(instr->value());
   5297   __ JumpIfNotSmi(value_register, &do_call);
   5298   __ mov(eax, Immediate(isolate()->factory()->number_string()));
   5299   __ jmp(&end);
   5300   __ bind(&do_call);
   5301   Callable callable = CodeFactory::Typeof(isolate());
   5302   CallCode(callable.code(), RelocInfo::CODE_TARGET, instr);
   5303   __ bind(&end);
   5304 }
   5305 
   5306 
   5307 void LCodeGen::DoTypeofIsAndBranch(LTypeofIsAndBranch* instr) {
   5308   Register input = ToRegister(instr->value());
   5309   Condition final_branch_condition = EmitTypeofIs(instr, input);
   5310   if (final_branch_condition != no_condition) {
   5311     EmitBranch(instr, final_branch_condition);
   5312   }
   5313 }
   5314 
   5315 
   5316 Condition LCodeGen::EmitTypeofIs(LTypeofIsAndBranch* instr, Register input) {
   5317   Label* true_label = instr->TrueLabel(chunk_);
   5318   Label* false_label = instr->FalseLabel(chunk_);
   5319   Handle<String> type_name = instr->type_literal();
   5320   int left_block = instr->TrueDestination(chunk_);
   5321   int right_block = instr->FalseDestination(chunk_);
   5322   int next_block = GetNextEmittedBlock();
   5323 
   5324   Label::Distance true_distance = left_block == next_block ? Label::kNear
   5325                                                            : Label::kFar;
   5326   Label::Distance false_distance = right_block == next_block ? Label::kNear
   5327                                                              : Label::kFar;
   5328   Condition final_branch_condition = no_condition;
   5329   if (String::Equals(type_name, factory()->number_string())) {
   5330     __ JumpIfSmi(input, true_label, true_distance);
   5331     __ cmp(FieldOperand(input, HeapObject::kMapOffset),
   5332            factory()->heap_number_map());
   5333     final_branch_condition = equal;
   5334 
   5335   } else if (String::Equals(type_name, factory()->string_string())) {
   5336     __ JumpIfSmi(input, false_label, false_distance);
   5337     __ CmpObjectType(input, FIRST_NONSTRING_TYPE, input);
   5338     final_branch_condition = below;
   5339 
   5340   } else if (String::Equals(type_name, factory()->symbol_string())) {
   5341     __ JumpIfSmi(input, false_label, false_distance);
   5342     __ CmpObjectType(input, SYMBOL_TYPE, input);
   5343     final_branch_condition = equal;
   5344 
   5345   } else if (String::Equals(type_name, factory()->boolean_string())) {
   5346     __ cmp(input, factory()->true_value());
   5347     __ j(equal, true_label, true_distance);
   5348     __ cmp(input, factory()->false_value());
   5349     final_branch_condition = equal;
   5350 
   5351   } else if (String::Equals(type_name, factory()->undefined_string())) {
   5352     __ cmp(input, factory()->null_value());
   5353     __ j(equal, false_label, false_distance);
   5354     __ JumpIfSmi(input, false_label, false_distance);
   5355     // Check for undetectable objects => true.
   5356     __ mov(input, FieldOperand(input, HeapObject::kMapOffset));
   5357     __ test_b(FieldOperand(input, Map::kBitFieldOffset),
   5358               Immediate(1 << Map::kIsUndetectable));
   5359     final_branch_condition = not_zero;
   5360 
   5361   } else if (String::Equals(type_name, factory()->function_string())) {
   5362     __ JumpIfSmi(input, false_label, false_distance);
   5363     // Check for callable and not undetectable objects => true.
   5364     __ mov(input, FieldOperand(input, HeapObject::kMapOffset));
   5365     __ movzx_b(input, FieldOperand(input, Map::kBitFieldOffset));
   5366     __ and_(input, (1 << Map::kIsCallable) | (1 << Map::kIsUndetectable));
   5367     __ cmp(input, 1 << Map::kIsCallable);
   5368     final_branch_condition = equal;
   5369 
   5370   } else if (String::Equals(type_name, factory()->object_string())) {
   5371     __ JumpIfSmi(input, false_label, false_distance);
   5372     __ cmp(input, factory()->null_value());
   5373     __ j(equal, true_label, true_distance);
   5374     STATIC_ASSERT(LAST_JS_RECEIVER_TYPE == LAST_TYPE);
   5375     __ CmpObjectType(input, FIRST_JS_RECEIVER_TYPE, input);
   5376     __ j(below, false_label, false_distance);
   5377     // Check for callable or undetectable objects => false.
   5378     __ test_b(FieldOperand(input, Map::kBitFieldOffset),
   5379               Immediate((1 << Map::kIsCallable) | (1 << Map::kIsUndetectable)));
   5380     final_branch_condition = zero;
   5381 
   5382 // clang-format off
   5383 #define SIMD128_TYPE(TYPE, Type, type, lane_count, lane_type)         \
   5384   } else if (String::Equals(type_name, factory()->type##_string())) { \
   5385     __ JumpIfSmi(input, false_label, false_distance);                 \
   5386     __ cmp(FieldOperand(input, HeapObject::kMapOffset),               \
   5387            factory()->type##_map());                                  \
   5388     final_branch_condition = equal;
   5389   SIMD128_TYPES(SIMD128_TYPE)
   5390 #undef SIMD128_TYPE
   5391     // clang-format on
   5392 
   5393   } else {
   5394     __ jmp(false_label, false_distance);
   5395   }
   5396   return final_branch_condition;
   5397 }
   5398 
   5399 
   5400 void LCodeGen::EnsureSpaceForLazyDeopt(int space_needed) {
   5401   if (info()->ShouldEnsureSpaceForLazyDeopt()) {
   5402     // Ensure that we have enough space after the previous lazy-bailout
   5403     // instruction for patching the code here.
   5404     int current_pc = masm()->pc_offset();
   5405     if (current_pc < last_lazy_deopt_pc_ + space_needed) {
   5406       int padding_size = last_lazy_deopt_pc_ + space_needed - current_pc;
   5407       __ Nop(padding_size);
   5408     }
   5409   }
   5410   last_lazy_deopt_pc_ = masm()->pc_offset();
   5411 }
   5412 
   5413 
   5414 void LCodeGen::DoLazyBailout(LLazyBailout* instr) {
   5415   last_lazy_deopt_pc_ = masm()->pc_offset();
   5416   DCHECK(instr->HasEnvironment());
   5417   LEnvironment* env = instr->environment();
   5418   RegisterEnvironmentForDeoptimization(env, Safepoint::kLazyDeopt);
   5419   safepoints_.RecordLazyDeoptimizationIndex(env->deoptimization_index());
   5420 }
   5421 
   5422 
   5423 void LCodeGen::DoDeoptimize(LDeoptimize* instr) {
   5424   Deoptimizer::BailoutType type = instr->hydrogen()->type();
   5425   // TODO(danno): Stubs expect all deopts to be lazy for historical reasons (the
   5426   // needed return address), even though the implementation of LAZY and EAGER is
   5427   // now identical. When LAZY is eventually completely folded into EAGER, remove
   5428   // the special case below.
   5429   if (info()->IsStub() && type == Deoptimizer::EAGER) {
   5430     type = Deoptimizer::LAZY;
   5431   }
   5432   DeoptimizeIf(no_condition, instr, instr->hydrogen()->reason(), type);
   5433 }
   5434 
   5435 
   5436 void LCodeGen::DoDummy(LDummy* instr) {
   5437   // Nothing to see here, move on!
   5438 }
   5439 
   5440 
   5441 void LCodeGen::DoDummyUse(LDummyUse* instr) {
   5442   // Nothing to see here, move on!
   5443 }
   5444 
   5445 
   5446 void LCodeGen::DoDeferredStackCheck(LStackCheck* instr) {
   5447   PushSafepointRegistersScope scope(this);
   5448   __ mov(esi, Operand(ebp, StandardFrameConstants::kContextOffset));
   5449   __ CallRuntimeSaveDoubles(Runtime::kStackGuard);
   5450   RecordSafepointWithLazyDeopt(
   5451       instr, RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS);
   5452   DCHECK(instr->HasEnvironment());
   5453   LEnvironment* env = instr->environment();
   5454   safepoints_.RecordLazyDeoptimizationIndex(env->deoptimization_index());
   5455 }
   5456 
   5457 
   5458 void LCodeGen::DoStackCheck(LStackCheck* instr) {
   5459   class DeferredStackCheck final : public LDeferredCode {
   5460    public:
   5461     DeferredStackCheck(LCodeGen* codegen,
   5462                        LStackCheck* instr,
   5463                        const X87Stack& x87_stack)
   5464         : LDeferredCode(codegen, x87_stack), instr_(instr) { }
   5465     void Generate() override { codegen()->DoDeferredStackCheck(instr_); }
   5466     LInstruction* instr() override { return instr_; }
   5467 
   5468    private:
   5469     LStackCheck* instr_;
   5470   };
   5471 
   5472   DCHECK(instr->HasEnvironment());
   5473   LEnvironment* env = instr->environment();
   5474   // There is no LLazyBailout instruction for stack-checks. We have to
   5475   // prepare for lazy deoptimization explicitly here.
   5476   if (instr->hydrogen()->is_function_entry()) {
   5477     // Perform stack overflow check.
   5478     Label done;
   5479     ExternalReference stack_limit =
   5480         ExternalReference::address_of_stack_limit(isolate());
   5481     __ cmp(esp, Operand::StaticVariable(stack_limit));
   5482     __ j(above_equal, &done, Label::kNear);
   5483 
   5484     DCHECK(instr->context()->IsRegister());
   5485     DCHECK(ToRegister(instr->context()).is(esi));
   5486     CallCode(isolate()->builtins()->StackCheck(),
   5487              RelocInfo::CODE_TARGET,
   5488              instr);
   5489     __ bind(&done);
   5490   } else {
   5491     DCHECK(instr->hydrogen()->is_backwards_branch());
   5492     // Perform stack overflow check if this goto needs it before jumping.
   5493     DeferredStackCheck* deferred_stack_check =
   5494         new(zone()) DeferredStackCheck(this, instr, x87_stack_);
   5495     ExternalReference stack_limit =
   5496         ExternalReference::address_of_stack_limit(isolate());
   5497     __ cmp(esp, Operand::StaticVariable(stack_limit));
   5498     __ j(below, deferred_stack_check->entry());
   5499     EnsureSpaceForLazyDeopt(Deoptimizer::patch_size());
   5500     __ bind(instr->done_label());
   5501     deferred_stack_check->SetExit(instr->done_label());
   5502     RegisterEnvironmentForDeoptimization(env, Safepoint::kLazyDeopt);
   5503     // Don't record a deoptimization index for the safepoint here.
   5504     // This will be done explicitly when emitting call and the safepoint in
   5505     // the deferred code.
   5506   }
   5507 }
   5508 
   5509 
   5510 void LCodeGen::DoOsrEntry(LOsrEntry* instr) {
   5511   // This is a pseudo-instruction that ensures that the environment here is
   5512   // properly registered for deoptimization and records the assembler's PC
   5513   // offset.
   5514   LEnvironment* environment = instr->environment();
   5515 
   5516   // If the environment were already registered, we would have no way of
   5517   // backpatching it with the spill slot operands.
   5518   DCHECK(!environment->HasBeenRegistered());
   5519   RegisterEnvironmentForDeoptimization(environment, Safepoint::kNoLazyDeopt);
   5520 
   5521   GenerateOsrPrologue();
   5522 }
   5523 
   5524 
   5525 void LCodeGen::DoForInPrepareMap(LForInPrepareMap* instr) {
   5526   DCHECK(ToRegister(instr->context()).is(esi));
   5527 
   5528   Label use_cache, call_runtime;
   5529   __ CheckEnumCache(&call_runtime);
   5530 
   5531   __ mov(eax, FieldOperand(eax, HeapObject::kMapOffset));
   5532   __ jmp(&use_cache, Label::kNear);
   5533 
   5534   // Get the set of properties to enumerate.
   5535   __ bind(&call_runtime);
   5536   __ push(eax);
   5537   CallRuntime(Runtime::kForInEnumerate, instr);
   5538   __ bind(&use_cache);
   5539 }
   5540 
   5541 
   5542 void LCodeGen::DoForInCacheArray(LForInCacheArray* instr) {
   5543   Register map = ToRegister(instr->map());
   5544   Register result = ToRegister(instr->result());
   5545   Label load_cache, done;
   5546   __ EnumLength(result, map);
   5547   __ cmp(result, Immediate(Smi::kZero));
   5548   __ j(not_equal, &load_cache, Label::kNear);
   5549   __ mov(result, isolate()->factory()->empty_fixed_array());
   5550   __ jmp(&done, Label::kNear);
   5551 
   5552   __ bind(&load_cache);
   5553   __ LoadInstanceDescriptors(map, result);
   5554   __ mov(result,
   5555          FieldOperand(result, DescriptorArray::kEnumCacheOffset));
   5556   __ mov(result,
   5557          FieldOperand(result, FixedArray::SizeFor(instr->idx())));
   5558   __ bind(&done);
   5559   __ test(result, result);
   5560   DeoptimizeIf(equal, instr, DeoptimizeReason::kNoCache);
   5561 }
   5562 
   5563 
   5564 void LCodeGen::DoCheckMapValue(LCheckMapValue* instr) {
   5565   Register object = ToRegister(instr->value());
   5566   __ cmp(ToRegister(instr->map()),
   5567          FieldOperand(object, HeapObject::kMapOffset));
   5568   DeoptimizeIf(not_equal, instr, DeoptimizeReason::kWrongMap);
   5569 }
   5570 
   5571 
   5572 void LCodeGen::DoDeferredLoadMutableDouble(LLoadFieldByIndex* instr,
   5573                                            Register object,
   5574                                            Register index) {
   5575   PushSafepointRegistersScope scope(this);
   5576   __ push(object);
   5577   __ push(index);
   5578   __ xor_(esi, esi);
   5579   __ CallRuntimeSaveDoubles(Runtime::kLoadMutableDouble);
   5580   RecordSafepointWithRegisters(
   5581       instr->pointer_map(), 2, Safepoint::kNoLazyDeopt);
   5582   __ StoreToSafepointRegisterSlot(object, eax);
   5583 }
   5584 
   5585 
   5586 void LCodeGen::DoLoadFieldByIndex(LLoadFieldByIndex* instr) {
   5587   class DeferredLoadMutableDouble final : public LDeferredCode {
   5588    public:
   5589     DeferredLoadMutableDouble(LCodeGen* codegen,
   5590                               LLoadFieldByIndex* instr,
   5591                               Register object,
   5592                               Register index,
   5593                               const X87Stack& x87_stack)
   5594         : LDeferredCode(codegen, x87_stack),
   5595           instr_(instr),
   5596           object_(object),
   5597           index_(index) {
   5598     }
   5599     void Generate() override {
   5600       codegen()->DoDeferredLoadMutableDouble(instr_, object_, index_);
   5601     }
   5602     LInstruction* instr() override { return instr_; }
   5603 
   5604    private:
   5605     LLoadFieldByIndex* instr_;
   5606     Register object_;
   5607     Register index_;
   5608   };
   5609 
   5610   Register object = ToRegister(instr->object());
   5611   Register index = ToRegister(instr->index());
   5612 
   5613   DeferredLoadMutableDouble* deferred;
   5614   deferred = new(zone()) DeferredLoadMutableDouble(
   5615       this, instr, object, index, x87_stack_);
   5616 
   5617   Label out_of_object, done;
   5618   __ test(index, Immediate(Smi::FromInt(1)));
   5619   __ j(not_zero, deferred->entry());
   5620 
   5621   __ sar(index, 1);
   5622 
   5623   __ cmp(index, Immediate(0));
   5624   __ j(less, &out_of_object, Label::kNear);
   5625   __ mov(object, FieldOperand(object,
   5626                               index,
   5627                               times_half_pointer_size,
   5628                               JSObject::kHeaderSize));
   5629   __ jmp(&done, Label::kNear);
   5630 
   5631   __ bind(&out_of_object);
   5632   __ mov(object, FieldOperand(object, JSObject::kPropertiesOffset));
   5633   __ neg(index);
   5634   // Index is now equal to out of object property index plus 1.
   5635   __ mov(object, FieldOperand(object,
   5636                               index,
   5637                               times_half_pointer_size,
   5638                               FixedArray::kHeaderSize - kPointerSize));
   5639   __ bind(deferred->exit());
   5640   __ bind(&done);
   5641 }
   5642 
   5643 #undef __
   5644 
   5645 }  // namespace internal
   5646 }  // namespace v8
   5647 
   5648 #endif  // V8_TARGET_ARCH_X87
   5649