1 /* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "stack.h" 18 19 #include "mirror/art_method-inl.h" 20 #include "mirror/class-inl.h" 21 #include "mirror/object.h" 22 #include "mirror/object-inl.h" 23 #include "mirror/object_array-inl.h" 24 #include "object_utils.h" 25 #include "thread_list.h" 26 #include "throw_location.h" 27 #include "vmap_table.h" 28 29 namespace art { 30 31 mirror::Object* ShadowFrame::GetThisObject() const { 32 mirror::ArtMethod* m = GetMethod(); 33 if (m->IsStatic()) { 34 return NULL; 35 } else if (m->IsNative()) { 36 return GetVRegReference(0); 37 } else { 38 const DexFile::CodeItem* code_item = MethodHelper(m).GetCodeItem(); 39 CHECK(code_item != NULL) << PrettyMethod(m); 40 uint16_t reg = code_item->registers_size_ - code_item->ins_size_; 41 return GetVRegReference(reg); 42 } 43 } 44 45 mirror::Object* ShadowFrame::GetThisObject(uint16_t num_ins) const { 46 mirror::ArtMethod* m = GetMethod(); 47 if (m->IsStatic()) { 48 return NULL; 49 } else { 50 return GetVRegReference(NumberOfVRegs() - num_ins); 51 } 52 } 53 54 ThrowLocation ShadowFrame::GetCurrentLocationForThrow() const { 55 return ThrowLocation(GetThisObject(), GetMethod(), GetDexPC()); 56 } 57 58 size_t ManagedStack::NumJniShadowFrameReferences() const { 59 size_t count = 0; 60 for (const ManagedStack* current_fragment = this; current_fragment != NULL; 61 current_fragment = current_fragment->GetLink()) { 62 for (ShadowFrame* current_frame = current_fragment->top_shadow_frame_; current_frame != NULL; 63 current_frame = current_frame->GetLink()) { 64 if (current_frame->GetMethod()->IsNative()) { 65 // The JNI ShadowFrame only contains references. (For indirect reference.) 66 count += current_frame->NumberOfVRegs(); 67 } 68 } 69 } 70 return count; 71 } 72 73 bool ManagedStack::ShadowFramesContain(mirror::Object** shadow_frame_entry) const { 74 for (const ManagedStack* current_fragment = this; current_fragment != NULL; 75 current_fragment = current_fragment->GetLink()) { 76 for (ShadowFrame* current_frame = current_fragment->top_shadow_frame_; current_frame != NULL; 77 current_frame = current_frame->GetLink()) { 78 if (current_frame->Contains(shadow_frame_entry)) { 79 return true; 80 } 81 } 82 } 83 return false; 84 } 85 86 StackVisitor::StackVisitor(Thread* thread, Context* context) 87 : thread_(thread), cur_shadow_frame_(NULL), 88 cur_quick_frame_(NULL), cur_quick_frame_pc_(0), num_frames_(0), cur_depth_(0), 89 context_(context) { 90 DCHECK(thread == Thread::Current() || thread->IsSuspended()) << *thread; 91 } 92 93 uint32_t StackVisitor::GetDexPc() const { 94 if (cur_shadow_frame_ != NULL) { 95 return cur_shadow_frame_->GetDexPC(); 96 } else if (cur_quick_frame_ != NULL) { 97 return GetMethod()->ToDexPc(cur_quick_frame_pc_); 98 } else { 99 return 0; 100 } 101 } 102 103 mirror::Object* StackVisitor::GetThisObject() const { 104 mirror::ArtMethod* m = GetMethod(); 105 if (m->IsStatic()) { 106 return NULL; 107 } else if (m->IsNative()) { 108 if (cur_quick_frame_ != NULL) { 109 StackIndirectReferenceTable* sirt = 110 reinterpret_cast<StackIndirectReferenceTable*>( 111 reinterpret_cast<char*>(cur_quick_frame_) + 112 m->GetSirtOffsetInBytes()); 113 return sirt->GetReference(0); 114 } else { 115 return cur_shadow_frame_->GetVRegReference(0); 116 } 117 } else { 118 const DexFile::CodeItem* code_item = MethodHelper(m).GetCodeItem(); 119 if (code_item == NULL) { 120 UNIMPLEMENTED(ERROR) << "Failed to determine this object of abstract or proxy method" 121 << PrettyMethod(m); 122 return NULL; 123 } else { 124 uint16_t reg = code_item->registers_size_ - code_item->ins_size_; 125 return reinterpret_cast<mirror::Object*>(GetVReg(m, reg, kReferenceVReg)); 126 } 127 } 128 } 129 130 size_t StackVisitor::GetNativePcOffset() const { 131 DCHECK(!IsShadowFrame()); 132 return GetMethod()->NativePcOffset(cur_quick_frame_pc_); 133 } 134 135 uint32_t StackVisitor::GetVReg(mirror::ArtMethod* m, uint16_t vreg, VRegKind kind) const { 136 if (cur_quick_frame_ != NULL) { 137 DCHECK(context_ != NULL); // You can't reliably read registers without a context. 138 DCHECK(m == GetMethod()); 139 const VmapTable vmap_table(m->GetVmapTable()); 140 uint32_t vmap_offset; 141 // TODO: IsInContext stops before spotting floating point registers. 142 if (vmap_table.IsInContext(vreg, kind, &vmap_offset)) { 143 bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg); 144 uint32_t spill_mask = is_float ? m->GetFpSpillMask() 145 : m->GetCoreSpillMask(); 146 return GetGPR(vmap_table.ComputeRegister(spill_mask, vmap_offset, kind)); 147 } else { 148 const DexFile::CodeItem* code_item = MethodHelper(m).GetCodeItem(); 149 DCHECK(code_item != NULL) << PrettyMethod(m); // Can't be NULL or how would we compile its instructions? 150 size_t frame_size = m->GetFrameSizeInBytes(); 151 return GetVReg(cur_quick_frame_, code_item, m->GetCoreSpillMask(), m->GetFpSpillMask(), 152 frame_size, vreg); 153 } 154 } else { 155 return cur_shadow_frame_->GetVReg(vreg); 156 } 157 } 158 159 void StackVisitor::SetVReg(mirror::ArtMethod* m, uint16_t vreg, uint32_t new_value, 160 VRegKind kind) { 161 if (cur_quick_frame_ != NULL) { 162 DCHECK(context_ != NULL); // You can't reliably write registers without a context. 163 DCHECK(m == GetMethod()); 164 const VmapTable vmap_table(m->GetVmapTable()); 165 uint32_t vmap_offset; 166 // TODO: IsInContext stops before spotting floating point registers. 167 if (vmap_table.IsInContext(vreg, kind, &vmap_offset)) { 168 bool is_float = (kind == kFloatVReg) || (kind == kDoubleLoVReg) || (kind == kDoubleHiVReg); 169 uint32_t spill_mask = is_float ? m->GetFpSpillMask() : m->GetCoreSpillMask(); 170 const uint32_t reg = vmap_table.ComputeRegister(spill_mask, vmap_offset, kReferenceVReg); 171 SetGPR(reg, new_value); 172 } else { 173 const DexFile::CodeItem* code_item = MethodHelper(m).GetCodeItem(); 174 DCHECK(code_item != NULL) << PrettyMethod(m); // Can't be NULL or how would we compile its instructions? 175 uint32_t core_spills = m->GetCoreSpillMask(); 176 uint32_t fp_spills = m->GetFpSpillMask(); 177 size_t frame_size = m->GetFrameSizeInBytes(); 178 int offset = GetVRegOffset(code_item, core_spills, fp_spills, frame_size, vreg); 179 byte* vreg_addr = reinterpret_cast<byte*>(GetCurrentQuickFrame()) + offset; 180 *reinterpret_cast<uint32_t*>(vreg_addr) = new_value; 181 } 182 } else { 183 return cur_shadow_frame_->SetVReg(vreg, new_value); 184 } 185 } 186 187 uintptr_t StackVisitor::GetGPR(uint32_t reg) const { 188 DCHECK(cur_quick_frame_ != NULL) << "This is a quick frame routine"; 189 return context_->GetGPR(reg); 190 } 191 192 void StackVisitor::SetGPR(uint32_t reg, uintptr_t value) { 193 DCHECK(cur_quick_frame_ != NULL) << "This is a quick frame routine"; 194 context_->SetGPR(reg, value); 195 } 196 197 uintptr_t StackVisitor::GetReturnPc() const { 198 mirror::ArtMethod** sp = GetCurrentQuickFrame(); 199 DCHECK(sp != NULL); 200 byte* pc_addr = reinterpret_cast<byte*>(sp) + GetMethod()->GetReturnPcOffsetInBytes(); 201 return *reinterpret_cast<uintptr_t*>(pc_addr); 202 } 203 204 void StackVisitor::SetReturnPc(uintptr_t new_ret_pc) { 205 mirror::ArtMethod** sp = GetCurrentQuickFrame(); 206 CHECK(sp != NULL); 207 byte* pc_addr = reinterpret_cast<byte*>(sp) + GetMethod()->GetReturnPcOffsetInBytes(); 208 *reinterpret_cast<uintptr_t*>(pc_addr) = new_ret_pc; 209 } 210 211 size_t StackVisitor::ComputeNumFrames(Thread* thread) { 212 struct NumFramesVisitor : public StackVisitor { 213 explicit NumFramesVisitor(Thread* thread) 214 : StackVisitor(thread, NULL), frames(0) {} 215 216 virtual bool VisitFrame() { 217 frames++; 218 return true; 219 } 220 221 size_t frames; 222 }; 223 NumFramesVisitor visitor(thread); 224 visitor.WalkStack(true); 225 return visitor.frames; 226 } 227 228 void StackVisitor::DescribeStack(Thread* thread) { 229 struct DescribeStackVisitor : public StackVisitor { 230 explicit DescribeStackVisitor(Thread* thread) 231 : StackVisitor(thread, NULL) {} 232 233 virtual bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 234 LOG(INFO) << "Frame Id=" << GetFrameId() << " " << DescribeLocation(); 235 return true; 236 } 237 }; 238 DescribeStackVisitor visitor(thread); 239 visitor.WalkStack(true); 240 } 241 242 std::string StackVisitor::DescribeLocation() const { 243 std::string result("Visiting method '"); 244 mirror::ArtMethod* m = GetMethod(); 245 if (m == NULL) { 246 return "upcall"; 247 } 248 result += PrettyMethod(m); 249 result += StringPrintf("' at dex PC 0x%04zx", GetDexPc()); 250 if (!IsShadowFrame()) { 251 result += StringPrintf(" (native PC %p)", reinterpret_cast<void*>(GetCurrentQuickFramePc())); 252 } 253 return result; 254 } 255 256 instrumentation::InstrumentationStackFrame StackVisitor::GetInstrumentationStackFrame(uint32_t depth) const { 257 return thread_->GetInstrumentationStack()->at(depth); 258 } 259 260 void StackVisitor::SanityCheckFrame() const { 261 #ifndef NDEBUG 262 mirror::ArtMethod* method = GetMethod(); 263 CHECK(method->GetClass() == mirror::ArtMethod::GetJavaLangReflectArtMethod()); 264 if (cur_quick_frame_ != NULL) { 265 method->AssertPcIsWithinCode(cur_quick_frame_pc_); 266 // Frame sanity. 267 size_t frame_size = method->GetFrameSizeInBytes(); 268 CHECK_NE(frame_size, 0u); 269 // A rough guess at an upper size we expect to see for a frame. The 256 is 270 // a dex register limit. The 16 incorporates callee save spills and 271 // outgoing argument set up. 272 const size_t kMaxExpectedFrameSize = 256 * sizeof(word) + 16; 273 CHECK_LE(frame_size, kMaxExpectedFrameSize); 274 size_t return_pc_offset = method->GetReturnPcOffsetInBytes(); 275 CHECK_LT(return_pc_offset, frame_size); 276 } 277 #endif 278 } 279 280 void StackVisitor::WalkStack(bool include_transitions) { 281 DCHECK(thread_ == Thread::Current() || thread_->IsSuspended()); 282 CHECK_EQ(cur_depth_, 0U); 283 bool exit_stubs_installed = Runtime::Current()->GetInstrumentation()->AreExitStubsInstalled(); 284 uint32_t instrumentation_stack_depth = 0; 285 for (const ManagedStack* current_fragment = thread_->GetManagedStack(); current_fragment != NULL; 286 current_fragment = current_fragment->GetLink()) { 287 cur_shadow_frame_ = current_fragment->GetTopShadowFrame(); 288 cur_quick_frame_ = current_fragment->GetTopQuickFrame(); 289 cur_quick_frame_pc_ = current_fragment->GetTopQuickFramePc(); 290 if (cur_quick_frame_ != NULL) { // Handle quick stack frames. 291 // Can't be both a shadow and a quick fragment. 292 DCHECK(current_fragment->GetTopShadowFrame() == NULL); 293 mirror::ArtMethod* method = *cur_quick_frame_; 294 while (method != NULL) { 295 SanityCheckFrame(); 296 bool should_continue = VisitFrame(); 297 if (UNLIKELY(!should_continue)) { 298 return; 299 } 300 if (context_ != NULL) { 301 context_->FillCalleeSaves(*this); 302 } 303 size_t frame_size = method->GetFrameSizeInBytes(); 304 // Compute PC for next stack frame from return PC. 305 size_t return_pc_offset = method->GetReturnPcOffsetInBytes(); 306 byte* return_pc_addr = reinterpret_cast<byte*>(cur_quick_frame_) + return_pc_offset; 307 uintptr_t return_pc = *reinterpret_cast<uintptr_t*>(return_pc_addr); 308 if (UNLIKELY(exit_stubs_installed)) { 309 // While profiling, the return pc is restored from the side stack, except when walking 310 // the stack for an exception where the side stack will be unwound in VisitFrame. 311 if (GetQuickInstrumentationExitPc() == return_pc) { 312 instrumentation::InstrumentationStackFrame instrumentation_frame = 313 GetInstrumentationStackFrame(instrumentation_stack_depth); 314 instrumentation_stack_depth++; 315 if (GetMethod() == Runtime::Current()->GetCalleeSaveMethod(Runtime::kSaveAll)) { 316 // Skip runtime save all callee frames which are used to deliver exceptions. 317 } else if (instrumentation_frame.interpreter_entry_) { 318 mirror::ArtMethod* callee = Runtime::Current()->GetCalleeSaveMethod(Runtime::kRefsAndArgs); 319 CHECK_EQ(GetMethod(), callee) << "Expected: " << PrettyMethod(callee) << " Found: " 320 << PrettyMethod(GetMethod()); 321 } else if (instrumentation_frame.method_ != GetMethod()) { 322 LOG(FATAL) << "Expected: " << PrettyMethod(instrumentation_frame.method_) 323 << " Found: " << PrettyMethod(GetMethod()); 324 } 325 if (num_frames_ != 0) { 326 // Check agreement of frame Ids only if num_frames_ is computed to avoid infinite 327 // recursion. 328 CHECK(instrumentation_frame.frame_id_ == GetFrameId()) 329 << "Expected: " << instrumentation_frame.frame_id_ 330 << " Found: " << GetFrameId(); 331 } 332 return_pc = instrumentation_frame.return_pc_; 333 } 334 } 335 cur_quick_frame_pc_ = return_pc; 336 byte* next_frame = reinterpret_cast<byte*>(cur_quick_frame_) + frame_size; 337 cur_quick_frame_ = reinterpret_cast<mirror::ArtMethod**>(next_frame); 338 cur_depth_++; 339 method = *cur_quick_frame_; 340 } 341 } else if (cur_shadow_frame_ != NULL) { 342 do { 343 SanityCheckFrame(); 344 bool should_continue = VisitFrame(); 345 if (UNLIKELY(!should_continue)) { 346 return; 347 } 348 cur_depth_++; 349 cur_shadow_frame_ = cur_shadow_frame_->GetLink(); 350 } while (cur_shadow_frame_ != NULL); 351 } 352 if (include_transitions) { 353 bool should_continue = VisitFrame(); 354 if (!should_continue) { 355 return; 356 } 357 } 358 cur_depth_++; 359 } 360 if (num_frames_ != 0) { 361 CHECK_EQ(cur_depth_, num_frames_); 362 } 363 } 364 365 } // namespace art 366
