1 //===- DAGISelMatcherGen.cpp - Matcher generator --------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "DAGISelMatcher.h" 11 #include "CodeGenDAGPatterns.h" 12 #include "CodeGenRegisters.h" 13 #include "llvm/TableGen/Record.h" 14 #include "llvm/ADT/DenseMap.h" 15 #include "llvm/ADT/SmallVector.h" 16 #include "llvm/ADT/StringMap.h" 17 #include <utility> 18 using namespace llvm; 19 20 21 /// getRegisterValueType - Look up and return the ValueType of the specified 22 /// register. If the register is a member of multiple register classes which 23 /// have different associated types, return MVT::Other. 24 static MVT::SimpleValueType getRegisterValueType(Record *R, 25 const CodeGenTarget &T) { 26 bool FoundRC = false; 27 MVT::SimpleValueType VT = MVT::Other; 28 const CodeGenRegister *Reg = T.getRegBank().getReg(R); 29 ArrayRef<CodeGenRegisterClass*> RCs = T.getRegBank().getRegClasses(); 30 31 for (unsigned rc = 0, e = RCs.size(); rc != e; ++rc) { 32 const CodeGenRegisterClass &RC = *RCs[rc]; 33 if (!RC.contains(Reg)) 34 continue; 35 36 if (!FoundRC) { 37 FoundRC = true; 38 VT = RC.getValueTypeNum(0); 39 continue; 40 } 41 42 // If this occurs in multiple register classes, they all have to agree. 43 assert(VT == RC.getValueTypeNum(0)); 44 } 45 return VT; 46 } 47 48 49 namespace { 50 class MatcherGen { 51 const PatternToMatch &Pattern; 52 const CodeGenDAGPatterns &CGP; 53 54 /// PatWithNoTypes - This is a clone of Pattern.getSrcPattern() that starts 55 /// out with all of the types removed. This allows us to insert type checks 56 /// as we scan the tree. 57 TreePatternNode *PatWithNoTypes; 58 59 /// VariableMap - A map from variable names ('$dst') to the recorded operand 60 /// number that they were captured as. These are biased by 1 to make 61 /// insertion easier. 62 StringMap<unsigned> VariableMap; 63 64 /// NextRecordedOperandNo - As we emit opcodes to record matched values in 65 /// the RecordedNodes array, this keeps track of which slot will be next to 66 /// record into. 67 unsigned NextRecordedOperandNo; 68 69 /// MatchedChainNodes - This maintains the position in the recorded nodes 70 /// array of all of the recorded input nodes that have chains. 71 SmallVector<unsigned, 2> MatchedChainNodes; 72 73 /// MatchedGlueResultNodes - This maintains the position in the recorded 74 /// nodes array of all of the recorded input nodes that have glue results. 75 SmallVector<unsigned, 2> MatchedGlueResultNodes; 76 77 /// MatchedComplexPatterns - This maintains a list of all of the 78 /// ComplexPatterns that we need to check. The patterns are known to have 79 /// names which were recorded. The second element of each pair is the first 80 /// slot number that the OPC_CheckComplexPat opcode drops the matched 81 /// results into. 82 SmallVector<std::pair<const TreePatternNode*, 83 unsigned>, 2> MatchedComplexPatterns; 84 85 /// PhysRegInputs - List list has an entry for each explicitly specified 86 /// physreg input to the pattern. The first elt is the Register node, the 87 /// second is the recorded slot number the input pattern match saved it in. 88 SmallVector<std::pair<Record*, unsigned>, 2> PhysRegInputs; 89 90 /// Matcher - This is the top level of the generated matcher, the result. 91 Matcher *TheMatcher; 92 93 /// CurPredicate - As we emit matcher nodes, this points to the latest check 94 /// which should have future checks stuck into its Next position. 95 Matcher *CurPredicate; 96 public: 97 MatcherGen(const PatternToMatch &pattern, const CodeGenDAGPatterns &cgp); 98 99 ~MatcherGen() { 100 delete PatWithNoTypes; 101 } 102 103 bool EmitMatcherCode(unsigned Variant); 104 void EmitResultCode(); 105 106 Matcher *GetMatcher() const { return TheMatcher; } 107 private: 108 void AddMatcher(Matcher *NewNode); 109 void InferPossibleTypes(); 110 111 // Matcher Generation. 112 void EmitMatchCode(const TreePatternNode *N, TreePatternNode *NodeNoTypes); 113 void EmitLeafMatchCode(const TreePatternNode *N); 114 void EmitOperatorMatchCode(const TreePatternNode *N, 115 TreePatternNode *NodeNoTypes); 116 117 // Result Code Generation. 118 unsigned getNamedArgumentSlot(StringRef Name) { 119 unsigned VarMapEntry = VariableMap[Name]; 120 assert(VarMapEntry != 0 && 121 "Variable referenced but not defined and not caught earlier!"); 122 return VarMapEntry-1; 123 } 124 125 /// GetInstPatternNode - Get the pattern for an instruction. 126 const TreePatternNode *GetInstPatternNode(const DAGInstruction &Ins, 127 const TreePatternNode *N); 128 129 void EmitResultOperand(const TreePatternNode *N, 130 SmallVectorImpl<unsigned> &ResultOps); 131 void EmitResultOfNamedOperand(const TreePatternNode *N, 132 SmallVectorImpl<unsigned> &ResultOps); 133 void EmitResultLeafAsOperand(const TreePatternNode *N, 134 SmallVectorImpl<unsigned> &ResultOps); 135 void EmitResultInstructionAsOperand(const TreePatternNode *N, 136 SmallVectorImpl<unsigned> &ResultOps); 137 void EmitResultSDNodeXFormAsOperand(const TreePatternNode *N, 138 SmallVectorImpl<unsigned> &ResultOps); 139 }; 140 141 } // end anon namespace. 142 143 MatcherGen::MatcherGen(const PatternToMatch &pattern, 144 const CodeGenDAGPatterns &cgp) 145 : Pattern(pattern), CGP(cgp), NextRecordedOperandNo(0), 146 TheMatcher(0), CurPredicate(0) { 147 // We need to produce the matcher tree for the patterns source pattern. To do 148 // this we need to match the structure as well as the types. To do the type 149 // matching, we want to figure out the fewest number of type checks we need to 150 // emit. For example, if there is only one integer type supported by a 151 // target, there should be no type comparisons at all for integer patterns! 152 // 153 // To figure out the fewest number of type checks needed, clone the pattern, 154 // remove the types, then perform type inference on the pattern as a whole. 155 // If there are unresolved types, emit an explicit check for those types, 156 // apply the type to the tree, then rerun type inference. Iterate until all 157 // types are resolved. 158 // 159 PatWithNoTypes = Pattern.getSrcPattern()->clone(); 160 PatWithNoTypes->RemoveAllTypes(); 161 162 // If there are types that are manifestly known, infer them. 163 InferPossibleTypes(); 164 } 165 166 /// InferPossibleTypes - As we emit the pattern, we end up generating type 167 /// checks and applying them to the 'PatWithNoTypes' tree. As we do this, we 168 /// want to propagate implied types as far throughout the tree as possible so 169 /// that we avoid doing redundant type checks. This does the type propagation. 170 void MatcherGen::InferPossibleTypes() { 171 // TP - Get *SOME* tree pattern, we don't care which. It is only used for 172 // diagnostics, which we know are impossible at this point. 173 TreePattern &TP = *CGP.pf_begin()->second; 174 175 try { 176 bool MadeChange = true; 177 while (MadeChange) 178 MadeChange = PatWithNoTypes->ApplyTypeConstraints(TP, 179 true/*Ignore reg constraints*/); 180 } catch (...) { 181 errs() << "Type constraint application shouldn't fail!"; 182 abort(); 183 } 184 } 185 186 187 /// AddMatcher - Add a matcher node to the current graph we're building. 188 void MatcherGen::AddMatcher(Matcher *NewNode) { 189 if (CurPredicate != 0) 190 CurPredicate->setNext(NewNode); 191 else 192 TheMatcher = NewNode; 193 CurPredicate = NewNode; 194 } 195 196 197 //===----------------------------------------------------------------------===// 198 // Pattern Match Generation 199 //===----------------------------------------------------------------------===// 200 201 /// EmitLeafMatchCode - Generate matching code for leaf nodes. 202 void MatcherGen::EmitLeafMatchCode(const TreePatternNode *N) { 203 assert(N->isLeaf() && "Not a leaf?"); 204 205 // Direct match against an integer constant. 206 if (IntInit *II = dynamic_cast<IntInit*>(N->getLeafValue())) { 207 // If this is the root of the dag we're matching, we emit a redundant opcode 208 // check to ensure that this gets folded into the normal top-level 209 // OpcodeSwitch. 210 if (N == Pattern.getSrcPattern()) { 211 const SDNodeInfo &NI = CGP.getSDNodeInfo(CGP.getSDNodeNamed("imm")); 212 AddMatcher(new CheckOpcodeMatcher(NI)); 213 } 214 215 return AddMatcher(new CheckIntegerMatcher(II->getValue())); 216 } 217 218 DefInit *DI = dynamic_cast<DefInit*>(N->getLeafValue()); 219 if (DI == 0) { 220 errs() << "Unknown leaf kind: " << *N << "\n"; 221 abort(); 222 } 223 224 Record *LeafRec = DI->getDef(); 225 if (// Handle register references. Nothing to do here, they always match. 226 LeafRec->isSubClassOf("RegisterClass") || 227 LeafRec->isSubClassOf("RegisterOperand") || 228 LeafRec->isSubClassOf("PointerLikeRegClass") || 229 LeafRec->isSubClassOf("SubRegIndex") || 230 // Place holder for SRCVALUE nodes. Nothing to do here. 231 LeafRec->getName() == "srcvalue") 232 return; 233 234 // If we have a physreg reference like (mul gpr:$src, EAX) then we need to 235 // record the register 236 if (LeafRec->isSubClassOf("Register")) { 237 AddMatcher(new RecordMatcher("physreg input "+LeafRec->getName(), 238 NextRecordedOperandNo)); 239 PhysRegInputs.push_back(std::make_pair(LeafRec, NextRecordedOperandNo++)); 240 return; 241 } 242 243 if (LeafRec->isSubClassOf("ValueType")) 244 return AddMatcher(new CheckValueTypeMatcher(LeafRec->getName())); 245 246 if (LeafRec->isSubClassOf("CondCode")) 247 return AddMatcher(new CheckCondCodeMatcher(LeafRec->getName())); 248 249 if (LeafRec->isSubClassOf("ComplexPattern")) { 250 // We can't model ComplexPattern uses that don't have their name taken yet. 251 // The OPC_CheckComplexPattern operation implicitly records the results. 252 if (N->getName().empty()) { 253 errs() << "We expect complex pattern uses to have names: " << *N << "\n"; 254 exit(1); 255 } 256 257 // Remember this ComplexPattern so that we can emit it after all the other 258 // structural matches are done. 259 MatchedComplexPatterns.push_back(std::make_pair(N, 0)); 260 return; 261 } 262 263 errs() << "Unknown leaf kind: " << *N << "\n"; 264 abort(); 265 } 266 267 void MatcherGen::EmitOperatorMatchCode(const TreePatternNode *N, 268 TreePatternNode *NodeNoTypes) { 269 assert(!N->isLeaf() && "Not an operator?"); 270 const SDNodeInfo &CInfo = CGP.getSDNodeInfo(N->getOperator()); 271 272 // If this is an 'and R, 1234' where the operation is AND/OR and the RHS is 273 // a constant without a predicate fn that has more that one bit set, handle 274 // this as a special case. This is usually for targets that have special 275 // handling of certain large constants (e.g. alpha with it's 8/16/32-bit 276 // handling stuff). Using these instructions is often far more efficient 277 // than materializing the constant. Unfortunately, both the instcombiner 278 // and the dag combiner can often infer that bits are dead, and thus drop 279 // them from the mask in the dag. For example, it might turn 'AND X, 255' 280 // into 'AND X, 254' if it knows the low bit is set. Emit code that checks 281 // to handle this. 282 if ((N->getOperator()->getName() == "and" || 283 N->getOperator()->getName() == "or") && 284 N->getChild(1)->isLeaf() && N->getChild(1)->getPredicateFns().empty() && 285 N->getPredicateFns().empty()) { 286 if (IntInit *II = dynamic_cast<IntInit*>(N->getChild(1)->getLeafValue())) { 287 if (!isPowerOf2_32(II->getValue())) { // Don't bother with single bits. 288 // If this is at the root of the pattern, we emit a redundant 289 // CheckOpcode so that the following checks get factored properly under 290 // a single opcode check. 291 if (N == Pattern.getSrcPattern()) 292 AddMatcher(new CheckOpcodeMatcher(CInfo)); 293 294 // Emit the CheckAndImm/CheckOrImm node. 295 if (N->getOperator()->getName() == "and") 296 AddMatcher(new CheckAndImmMatcher(II->getValue())); 297 else 298 AddMatcher(new CheckOrImmMatcher(II->getValue())); 299 300 // Match the LHS of the AND as appropriate. 301 AddMatcher(new MoveChildMatcher(0)); 302 EmitMatchCode(N->getChild(0), NodeNoTypes->getChild(0)); 303 AddMatcher(new MoveParentMatcher()); 304 return; 305 } 306 } 307 } 308 309 // Check that the current opcode lines up. 310 AddMatcher(new CheckOpcodeMatcher(CInfo)); 311 312 // If this node has memory references (i.e. is a load or store), tell the 313 // interpreter to capture them in the memref array. 314 if (N->NodeHasProperty(SDNPMemOperand, CGP)) 315 AddMatcher(new RecordMemRefMatcher()); 316 317 // If this node has a chain, then the chain is operand #0 is the SDNode, and 318 // the child numbers of the node are all offset by one. 319 unsigned OpNo = 0; 320 if (N->NodeHasProperty(SDNPHasChain, CGP)) { 321 // Record the node and remember it in our chained nodes list. 322 AddMatcher(new RecordMatcher("'" + N->getOperator()->getName() + 323 "' chained node", 324 NextRecordedOperandNo)); 325 // Remember all of the input chains our pattern will match. 326 MatchedChainNodes.push_back(NextRecordedOperandNo++); 327 328 // Don't look at the input chain when matching the tree pattern to the 329 // SDNode. 330 OpNo = 1; 331 332 // If this node is not the root and the subtree underneath it produces a 333 // chain, then the result of matching the node is also produce a chain. 334 // Beyond that, this means that we're also folding (at least) the root node 335 // into the node that produce the chain (for example, matching 336 // "(add reg, (load ptr))" as a add_with_memory on X86). This is 337 // problematic, if the 'reg' node also uses the load (say, its chain). 338 // Graphically: 339 // 340 // [LD] 341 // ^ ^ 342 // | \ DAG's like cheese. 343 // / | 344 // / [YY] 345 // | ^ 346 // [XX]--/ 347 // 348 // It would be invalid to fold XX and LD. In this case, folding the two 349 // nodes together would induce a cycle in the DAG, making it a 'cyclic DAG' 350 // To prevent this, we emit a dynamic check for legality before allowing 351 // this to be folded. 352 // 353 const TreePatternNode *Root = Pattern.getSrcPattern(); 354 if (N != Root) { // Not the root of the pattern. 355 // If there is a node between the root and this node, then we definitely 356 // need to emit the check. 357 bool NeedCheck = !Root->hasChild(N); 358 359 // If it *is* an immediate child of the root, we can still need a check if 360 // the root SDNode has multiple inputs. For us, this means that it is an 361 // intrinsic, has multiple operands, or has other inputs like chain or 362 // glue). 363 if (!NeedCheck) { 364 const SDNodeInfo &PInfo = CGP.getSDNodeInfo(Root->getOperator()); 365 NeedCheck = 366 Root->getOperator() == CGP.get_intrinsic_void_sdnode() || 367 Root->getOperator() == CGP.get_intrinsic_w_chain_sdnode() || 368 Root->getOperator() == CGP.get_intrinsic_wo_chain_sdnode() || 369 PInfo.getNumOperands() > 1 || 370 PInfo.hasProperty(SDNPHasChain) || 371 PInfo.hasProperty(SDNPInGlue) || 372 PInfo.hasProperty(SDNPOptInGlue); 373 } 374 375 if (NeedCheck) 376 AddMatcher(new CheckFoldableChainNodeMatcher()); 377 } 378 } 379 380 // If this node has an output glue and isn't the root, remember it. 381 if (N->NodeHasProperty(SDNPOutGlue, CGP) && 382 N != Pattern.getSrcPattern()) { 383 // TODO: This redundantly records nodes with both glues and chains. 384 385 // Record the node and remember it in our chained nodes list. 386 AddMatcher(new RecordMatcher("'" + N->getOperator()->getName() + 387 "' glue output node", 388 NextRecordedOperandNo)); 389 // Remember all of the nodes with output glue our pattern will match. 390 MatchedGlueResultNodes.push_back(NextRecordedOperandNo++); 391 } 392 393 // If this node is known to have an input glue or if it *might* have an input 394 // glue, capture it as the glue input of the pattern. 395 if (N->NodeHasProperty(SDNPOptInGlue, CGP) || 396 N->NodeHasProperty(SDNPInGlue, CGP)) 397 AddMatcher(new CaptureGlueInputMatcher()); 398 399 for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i, ++OpNo) { 400 // Get the code suitable for matching this child. Move to the child, check 401 // it then move back to the parent. 402 AddMatcher(new MoveChildMatcher(OpNo)); 403 EmitMatchCode(N->getChild(i), NodeNoTypes->getChild(i)); 404 AddMatcher(new MoveParentMatcher()); 405 } 406 } 407 408 409 void MatcherGen::EmitMatchCode(const TreePatternNode *N, 410 TreePatternNode *NodeNoTypes) { 411 // If N and NodeNoTypes don't agree on a type, then this is a case where we 412 // need to do a type check. Emit the check, apply the tyep to NodeNoTypes and 413 // reinfer any correlated types. 414 SmallVector<unsigned, 2> ResultsToTypeCheck; 415 416 for (unsigned i = 0, e = NodeNoTypes->getNumTypes(); i != e; ++i) { 417 if (NodeNoTypes->getExtType(i) == N->getExtType(i)) continue; 418 NodeNoTypes->setType(i, N->getExtType(i)); 419 InferPossibleTypes(); 420 ResultsToTypeCheck.push_back(i); 421 } 422 423 // If this node has a name associated with it, capture it in VariableMap. If 424 // we already saw this in the pattern, emit code to verify dagness. 425 if (!N->getName().empty()) { 426 unsigned &VarMapEntry = VariableMap[N->getName()]; 427 if (VarMapEntry == 0) { 428 // If it is a named node, we must emit a 'Record' opcode. 429 AddMatcher(new RecordMatcher("$" + N->getName(), NextRecordedOperandNo)); 430 VarMapEntry = ++NextRecordedOperandNo; 431 } else { 432 // If we get here, this is a second reference to a specific name. Since 433 // we already have checked that the first reference is valid, we don't 434 // have to recursively match it, just check that it's the same as the 435 // previously named thing. 436 AddMatcher(new CheckSameMatcher(VarMapEntry-1)); 437 return; 438 } 439 } 440 441 if (N->isLeaf()) 442 EmitLeafMatchCode(N); 443 else 444 EmitOperatorMatchCode(N, NodeNoTypes); 445 446 // If there are node predicates for this node, generate their checks. 447 for (unsigned i = 0, e = N->getPredicateFns().size(); i != e; ++i) 448 AddMatcher(new CheckPredicateMatcher(N->getPredicateFns()[i])); 449 450 for (unsigned i = 0, e = ResultsToTypeCheck.size(); i != e; ++i) 451 AddMatcher(new CheckTypeMatcher(N->getType(ResultsToTypeCheck[i]), 452 ResultsToTypeCheck[i])); 453 } 454 455 /// EmitMatcherCode - Generate the code that matches the predicate of this 456 /// pattern for the specified Variant. If the variant is invalid this returns 457 /// true and does not generate code, if it is valid, it returns false. 458 bool MatcherGen::EmitMatcherCode(unsigned Variant) { 459 // If the root of the pattern is a ComplexPattern and if it is specified to 460 // match some number of root opcodes, these are considered to be our variants. 461 // Depending on which variant we're generating code for, emit the root opcode 462 // check. 463 if (const ComplexPattern *CP = 464 Pattern.getSrcPattern()->getComplexPatternInfo(CGP)) { 465 const std::vector<Record*> &OpNodes = CP->getRootNodes(); 466 assert(!OpNodes.empty() &&"Complex Pattern must specify what it can match"); 467 if (Variant >= OpNodes.size()) return true; 468 469 AddMatcher(new CheckOpcodeMatcher(CGP.getSDNodeInfo(OpNodes[Variant]))); 470 } else { 471 if (Variant != 0) return true; 472 } 473 474 // Emit the matcher for the pattern structure and types. 475 EmitMatchCode(Pattern.getSrcPattern(), PatWithNoTypes); 476 477 // If the pattern has a predicate on it (e.g. only enabled when a subtarget 478 // feature is around, do the check). 479 if (!Pattern.getPredicateCheck().empty()) 480 AddMatcher(new CheckPatternPredicateMatcher(Pattern.getPredicateCheck())); 481 482 // Now that we've completed the structural type match, emit any ComplexPattern 483 // checks (e.g. addrmode matches). We emit this after the structural match 484 // because they are generally more expensive to evaluate and more difficult to 485 // factor. 486 for (unsigned i = 0, e = MatchedComplexPatterns.size(); i != e; ++i) { 487 const TreePatternNode *N = MatchedComplexPatterns[i].first; 488 489 // Remember where the results of this match get stuck. 490 MatchedComplexPatterns[i].second = NextRecordedOperandNo; 491 492 // Get the slot we recorded the value in from the name on the node. 493 unsigned RecNodeEntry = VariableMap[N->getName()]; 494 assert(!N->getName().empty() && RecNodeEntry && 495 "Complex pattern should have a name and slot"); 496 --RecNodeEntry; // Entries in VariableMap are biased. 497 498 const ComplexPattern &CP = 499 CGP.getComplexPattern(((DefInit*)N->getLeafValue())->getDef()); 500 501 // Emit a CheckComplexPat operation, which does the match (aborting if it 502 // fails) and pushes the matched operands onto the recorded nodes list. 503 AddMatcher(new CheckComplexPatMatcher(CP, RecNodeEntry, 504 N->getName(), NextRecordedOperandNo)); 505 506 // Record the right number of operands. 507 NextRecordedOperandNo += CP.getNumOperands(); 508 if (CP.hasProperty(SDNPHasChain)) { 509 // If the complex pattern has a chain, then we need to keep track of the 510 // fact that we just recorded a chain input. The chain input will be 511 // matched as the last operand of the predicate if it was successful. 512 ++NextRecordedOperandNo; // Chained node operand. 513 514 // It is the last operand recorded. 515 assert(NextRecordedOperandNo > 1 && 516 "Should have recorded input/result chains at least!"); 517 MatchedChainNodes.push_back(NextRecordedOperandNo-1); 518 } 519 520 // TODO: Complex patterns can't have output glues, if they did, we'd want 521 // to record them. 522 } 523 524 return false; 525 } 526 527 528 //===----------------------------------------------------------------------===// 529 // Node Result Generation 530 //===----------------------------------------------------------------------===// 531 532 void MatcherGen::EmitResultOfNamedOperand(const TreePatternNode *N, 533 SmallVectorImpl<unsigned> &ResultOps){ 534 assert(!N->getName().empty() && "Operand not named!"); 535 536 // A reference to a complex pattern gets all of the results of the complex 537 // pattern's match. 538 if (const ComplexPattern *CP = N->getComplexPatternInfo(CGP)) { 539 unsigned SlotNo = 0; 540 for (unsigned i = 0, e = MatchedComplexPatterns.size(); i != e; ++i) 541 if (MatchedComplexPatterns[i].first->getName() == N->getName()) { 542 SlotNo = MatchedComplexPatterns[i].second; 543 break; 544 } 545 assert(SlotNo != 0 && "Didn't get a slot number assigned?"); 546 547 // The first slot entry is the node itself, the subsequent entries are the 548 // matched values. 549 for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i) 550 ResultOps.push_back(SlotNo+i); 551 return; 552 } 553 554 unsigned SlotNo = getNamedArgumentSlot(N->getName()); 555 556 // If this is an 'imm' or 'fpimm' node, make sure to convert it to the target 557 // version of the immediate so that it doesn't get selected due to some other 558 // node use. 559 if (!N->isLeaf()) { 560 StringRef OperatorName = N->getOperator()->getName(); 561 if (OperatorName == "imm" || OperatorName == "fpimm") { 562 AddMatcher(new EmitConvertToTargetMatcher(SlotNo)); 563 ResultOps.push_back(NextRecordedOperandNo++); 564 return; 565 } 566 } 567 568 ResultOps.push_back(SlotNo); 569 } 570 571 void MatcherGen::EmitResultLeafAsOperand(const TreePatternNode *N, 572 SmallVectorImpl<unsigned> &ResultOps) { 573 assert(N->isLeaf() && "Must be a leaf"); 574 575 if (IntInit *II = dynamic_cast<IntInit*>(N->getLeafValue())) { 576 AddMatcher(new EmitIntegerMatcher(II->getValue(), N->getType(0))); 577 ResultOps.push_back(NextRecordedOperandNo++); 578 return; 579 } 580 581 // If this is an explicit register reference, handle it. 582 if (DefInit *DI = dynamic_cast<DefInit*>(N->getLeafValue())) { 583 Record *Def = DI->getDef(); 584 if (Def->isSubClassOf("Register")) { 585 const CodeGenRegister *Reg = 586 CGP.getTargetInfo().getRegBank().getReg(Def); 587 AddMatcher(new EmitRegisterMatcher(Reg, N->getType(0))); 588 ResultOps.push_back(NextRecordedOperandNo++); 589 return; 590 } 591 592 if (Def->getName() == "zero_reg") { 593 AddMatcher(new EmitRegisterMatcher(0, N->getType(0))); 594 ResultOps.push_back(NextRecordedOperandNo++); 595 return; 596 } 597 598 // Handle a reference to a register class. This is used 599 // in COPY_TO_SUBREG instructions. 600 if (Def->isSubClassOf("RegisterOperand")) 601 Def = Def->getValueAsDef("RegClass"); 602 if (Def->isSubClassOf("RegisterClass")) { 603 std::string Value = getQualifiedName(Def) + "RegClassID"; 604 AddMatcher(new EmitStringIntegerMatcher(Value, MVT::i32)); 605 ResultOps.push_back(NextRecordedOperandNo++); 606 return; 607 } 608 609 // Handle a subregister index. This is used for INSERT_SUBREG etc. 610 if (Def->isSubClassOf("SubRegIndex")) { 611 std::string Value = getQualifiedName(Def); 612 AddMatcher(new EmitStringIntegerMatcher(Value, MVT::i32)); 613 ResultOps.push_back(NextRecordedOperandNo++); 614 return; 615 } 616 } 617 618 errs() << "unhandled leaf node: \n"; 619 N->dump(); 620 } 621 622 /// GetInstPatternNode - Get the pattern for an instruction. 623 /// 624 const TreePatternNode *MatcherGen:: 625 GetInstPatternNode(const DAGInstruction &Inst, const TreePatternNode *N) { 626 const TreePattern *InstPat = Inst.getPattern(); 627 628 // FIXME2?: Assume actual pattern comes before "implicit". 629 TreePatternNode *InstPatNode; 630 if (InstPat) 631 InstPatNode = InstPat->getTree(0); 632 else if (/*isRoot*/ N == Pattern.getDstPattern()) 633 InstPatNode = Pattern.getSrcPattern(); 634 else 635 return 0; 636 637 if (InstPatNode && !InstPatNode->isLeaf() && 638 InstPatNode->getOperator()->getName() == "set") 639 InstPatNode = InstPatNode->getChild(InstPatNode->getNumChildren()-1); 640 641 return InstPatNode; 642 } 643 644 static bool 645 mayInstNodeLoadOrStore(const TreePatternNode *N, 646 const CodeGenDAGPatterns &CGP) { 647 Record *Op = N->getOperator(); 648 const CodeGenTarget &CGT = CGP.getTargetInfo(); 649 CodeGenInstruction &II = CGT.getInstruction(Op); 650 return II.mayLoad || II.mayStore; 651 } 652 653 static unsigned 654 numNodesThatMayLoadOrStore(const TreePatternNode *N, 655 const CodeGenDAGPatterns &CGP) { 656 if (N->isLeaf()) 657 return 0; 658 659 Record *OpRec = N->getOperator(); 660 if (!OpRec->isSubClassOf("Instruction")) 661 return 0; 662 663 unsigned Count = 0; 664 if (mayInstNodeLoadOrStore(N, CGP)) 665 ++Count; 666 667 for (unsigned i = 0, e = N->getNumChildren(); i != e; ++i) 668 Count += numNodesThatMayLoadOrStore(N->getChild(i), CGP); 669 670 return Count; 671 } 672 673 void MatcherGen:: 674 EmitResultInstructionAsOperand(const TreePatternNode *N, 675 SmallVectorImpl<unsigned> &OutputOps) { 676 Record *Op = N->getOperator(); 677 const CodeGenTarget &CGT = CGP.getTargetInfo(); 678 CodeGenInstruction &II = CGT.getInstruction(Op); 679 const DAGInstruction &Inst = CGP.getInstruction(Op); 680 681 // If we can, get the pattern for the instruction we're generating. We derive 682 // a variety of information from this pattern, such as whether it has a chain. 683 // 684 // FIXME2: This is extremely dubious for several reasons, not the least of 685 // which it gives special status to instructions with patterns that Pat<> 686 // nodes can't duplicate. 687 const TreePatternNode *InstPatNode = GetInstPatternNode(Inst, N); 688 689 // NodeHasChain - Whether the instruction node we're creating takes chains. 690 bool NodeHasChain = InstPatNode && 691 InstPatNode->TreeHasProperty(SDNPHasChain, CGP); 692 693 bool isRoot = N == Pattern.getDstPattern(); 694 695 // TreeHasOutGlue - True if this tree has glue. 696 bool TreeHasInGlue = false, TreeHasOutGlue = false; 697 if (isRoot) { 698 const TreePatternNode *SrcPat = Pattern.getSrcPattern(); 699 TreeHasInGlue = SrcPat->TreeHasProperty(SDNPOptInGlue, CGP) || 700 SrcPat->TreeHasProperty(SDNPInGlue, CGP); 701 702 // FIXME2: this is checking the entire pattern, not just the node in 703 // question, doing this just for the root seems like a total hack. 704 TreeHasOutGlue = SrcPat->TreeHasProperty(SDNPOutGlue, CGP); 705 } 706 707 // NumResults - This is the number of results produced by the instruction in 708 // the "outs" list. 709 unsigned NumResults = Inst.getNumResults(); 710 711 // Loop over all of the operands of the instruction pattern, emitting code 712 // to fill them all in. The node 'N' usually has number children equal to 713 // the number of input operands of the instruction. However, in cases 714 // where there are predicate operands for an instruction, we need to fill 715 // in the 'execute always' values. Match up the node operands to the 716 // instruction operands to do this. 717 SmallVector<unsigned, 8> InstOps; 718 for (unsigned ChildNo = 0, InstOpNo = NumResults, e = II.Operands.size(); 719 InstOpNo != e; ++InstOpNo) { 720 721 // Determine what to emit for this operand. 722 Record *OperandNode = II.Operands[InstOpNo].Rec; 723 if ((OperandNode->isSubClassOf("PredicateOperand") || 724 OperandNode->isSubClassOf("OptionalDefOperand")) && 725 !CGP.getDefaultOperand(OperandNode).DefaultOps.empty()) { 726 // This is a predicate or optional def operand; emit the 727 // 'default ops' operands. 728 const DAGDefaultOperand &DefaultOp 729 = CGP.getDefaultOperand(OperandNode); 730 for (unsigned i = 0, e = DefaultOp.DefaultOps.size(); i != e; ++i) 731 EmitResultOperand(DefaultOp.DefaultOps[i], InstOps); 732 continue; 733 } 734 735 const TreePatternNode *Child = N->getChild(ChildNo); 736 737 // Otherwise this is a normal operand or a predicate operand without 738 // 'execute always'; emit it. 739 unsigned BeforeAddingNumOps = InstOps.size(); 740 EmitResultOperand(Child, InstOps); 741 assert(InstOps.size() > BeforeAddingNumOps && "Didn't add any operands"); 742 743 // If the operand is an instruction and it produced multiple results, just 744 // take the first one. 745 if (!Child->isLeaf() && Child->getOperator()->isSubClassOf("Instruction")) 746 InstOps.resize(BeforeAddingNumOps+1); 747 748 ++ChildNo; 749 } 750 751 // If this node has input glue or explicitly specified input physregs, we 752 // need to add chained and glued copyfromreg nodes and materialize the glue 753 // input. 754 if (isRoot && !PhysRegInputs.empty()) { 755 // Emit all of the CopyToReg nodes for the input physical registers. These 756 // occur in patterns like (mul:i8 AL:i8, GR8:i8:$src). 757 for (unsigned i = 0, e = PhysRegInputs.size(); i != e; ++i) 758 AddMatcher(new EmitCopyToRegMatcher(PhysRegInputs[i].second, 759 PhysRegInputs[i].first)); 760 // Even if the node has no other glue inputs, the resultant node must be 761 // glued to the CopyFromReg nodes we just generated. 762 TreeHasInGlue = true; 763 } 764 765 // Result order: node results, chain, glue 766 767 // Determine the result types. 768 SmallVector<MVT::SimpleValueType, 4> ResultVTs; 769 for (unsigned i = 0, e = N->getNumTypes(); i != e; ++i) 770 ResultVTs.push_back(N->getType(i)); 771 772 // If this is the root instruction of a pattern that has physical registers in 773 // its result pattern, add output VTs for them. For example, X86 has: 774 // (set AL, (mul ...)) 775 // This also handles implicit results like: 776 // (implicit EFLAGS) 777 if (isRoot && !Pattern.getDstRegs().empty()) { 778 // If the root came from an implicit def in the instruction handling stuff, 779 // don't re-add it. 780 Record *HandledReg = 0; 781 if (II.HasOneImplicitDefWithKnownVT(CGT) != MVT::Other) 782 HandledReg = II.ImplicitDefs[0]; 783 784 for (unsigned i = 0; i != Pattern.getDstRegs().size(); ++i) { 785 Record *Reg = Pattern.getDstRegs()[i]; 786 if (!Reg->isSubClassOf("Register") || Reg == HandledReg) continue; 787 ResultVTs.push_back(getRegisterValueType(Reg, CGT)); 788 } 789 } 790 791 // If this is the root of the pattern and the pattern we're matching includes 792 // a node that is variadic, mark the generated node as variadic so that it 793 // gets the excess operands from the input DAG. 794 int NumFixedArityOperands = -1; 795 if (isRoot && 796 (Pattern.getSrcPattern()->NodeHasProperty(SDNPVariadic, CGP))) 797 NumFixedArityOperands = Pattern.getSrcPattern()->getNumChildren(); 798 799 // If this is the root node and multiple matched nodes in the input pattern 800 // have MemRefs in them, have the interpreter collect them and plop them onto 801 // this node. If there is just one node with MemRefs, leave them on that node 802 // even if it is not the root. 803 // 804 // FIXME3: This is actively incorrect for result patterns with multiple 805 // memory-referencing instructions. 806 bool PatternHasMemOperands = 807 Pattern.getSrcPattern()->TreeHasProperty(SDNPMemOperand, CGP); 808 809 bool NodeHasMemRefs = false; 810 if (PatternHasMemOperands) { 811 unsigned NumNodesThatLoadOrStore = 812 numNodesThatMayLoadOrStore(Pattern.getDstPattern(), CGP); 813 bool NodeIsUniqueLoadOrStore = mayInstNodeLoadOrStore(N, CGP) && 814 NumNodesThatLoadOrStore == 1; 815 NodeHasMemRefs = 816 NodeIsUniqueLoadOrStore || (isRoot && (mayInstNodeLoadOrStore(N, CGP) || 817 NumNodesThatLoadOrStore != 1)); 818 } 819 820 assert((!ResultVTs.empty() || TreeHasOutGlue || NodeHasChain) && 821 "Node has no result"); 822 823 AddMatcher(new EmitNodeMatcher(II.Namespace+"::"+II.TheDef->getName(), 824 ResultVTs.data(), ResultVTs.size(), 825 InstOps.data(), InstOps.size(), 826 NodeHasChain, TreeHasInGlue, TreeHasOutGlue, 827 NodeHasMemRefs, NumFixedArityOperands, 828 NextRecordedOperandNo)); 829 830 // The non-chain and non-glue results of the newly emitted node get recorded. 831 for (unsigned i = 0, e = ResultVTs.size(); i != e; ++i) { 832 if (ResultVTs[i] == MVT::Other || ResultVTs[i] == MVT::Glue) break; 833 OutputOps.push_back(NextRecordedOperandNo++); 834 } 835 } 836 837 void MatcherGen:: 838 EmitResultSDNodeXFormAsOperand(const TreePatternNode *N, 839 SmallVectorImpl<unsigned> &ResultOps) { 840 assert(N->getOperator()->isSubClassOf("SDNodeXForm") && "Not SDNodeXForm?"); 841 842 // Emit the operand. 843 SmallVector<unsigned, 8> InputOps; 844 845 // FIXME2: Could easily generalize this to support multiple inputs and outputs 846 // to the SDNodeXForm. For now we just support one input and one output like 847 // the old instruction selector. 848 assert(N->getNumChildren() == 1); 849 EmitResultOperand(N->getChild(0), InputOps); 850 851 // The input currently must have produced exactly one result. 852 assert(InputOps.size() == 1 && "Unexpected input to SDNodeXForm"); 853 854 AddMatcher(new EmitNodeXFormMatcher(InputOps[0], N->getOperator())); 855 ResultOps.push_back(NextRecordedOperandNo++); 856 } 857 858 void MatcherGen::EmitResultOperand(const TreePatternNode *N, 859 SmallVectorImpl<unsigned> &ResultOps) { 860 // This is something selected from the pattern we matched. 861 if (!N->getName().empty()) 862 return EmitResultOfNamedOperand(N, ResultOps); 863 864 if (N->isLeaf()) 865 return EmitResultLeafAsOperand(N, ResultOps); 866 867 Record *OpRec = N->getOperator(); 868 if (OpRec->isSubClassOf("Instruction")) 869 return EmitResultInstructionAsOperand(N, ResultOps); 870 if (OpRec->isSubClassOf("SDNodeXForm")) 871 return EmitResultSDNodeXFormAsOperand(N, ResultOps); 872 errs() << "Unknown result node to emit code for: " << *N << '\n'; 873 throw std::string("Unknown node in result pattern!"); 874 } 875 876 void MatcherGen::EmitResultCode() { 877 // Patterns that match nodes with (potentially multiple) chain inputs have to 878 // merge them together into a token factor. This informs the generated code 879 // what all the chained nodes are. 880 if (!MatchedChainNodes.empty()) 881 AddMatcher(new EmitMergeInputChainsMatcher 882 (MatchedChainNodes.data(), MatchedChainNodes.size())); 883 884 // Codegen the root of the result pattern, capturing the resulting values. 885 SmallVector<unsigned, 8> Ops; 886 EmitResultOperand(Pattern.getDstPattern(), Ops); 887 888 // At this point, we have however many values the result pattern produces. 889 // However, the input pattern might not need all of these. If there are 890 // excess values at the end (such as implicit defs of condition codes etc) 891 // just lop them off. This doesn't need to worry about glue or chains, just 892 // explicit results. 893 // 894 unsigned NumSrcResults = Pattern.getSrcPattern()->getNumTypes(); 895 896 // If the pattern also has (implicit) results, count them as well. 897 if (!Pattern.getDstRegs().empty()) { 898 // If the root came from an implicit def in the instruction handling stuff, 899 // don't re-add it. 900 Record *HandledReg = 0; 901 const TreePatternNode *DstPat = Pattern.getDstPattern(); 902 if (!DstPat->isLeaf() &&DstPat->getOperator()->isSubClassOf("Instruction")){ 903 const CodeGenTarget &CGT = CGP.getTargetInfo(); 904 CodeGenInstruction &II = CGT.getInstruction(DstPat->getOperator()); 905 906 if (II.HasOneImplicitDefWithKnownVT(CGT) != MVT::Other) 907 HandledReg = II.ImplicitDefs[0]; 908 } 909 910 for (unsigned i = 0; i != Pattern.getDstRegs().size(); ++i) { 911 Record *Reg = Pattern.getDstRegs()[i]; 912 if (!Reg->isSubClassOf("Register") || Reg == HandledReg) continue; 913 ++NumSrcResults; 914 } 915 } 916 917 assert(Ops.size() >= NumSrcResults && "Didn't provide enough results"); 918 Ops.resize(NumSrcResults); 919 920 // If the matched pattern covers nodes which define a glue result, emit a node 921 // that tells the matcher about them so that it can update their results. 922 if (!MatchedGlueResultNodes.empty()) 923 AddMatcher(new MarkGlueResultsMatcher(MatchedGlueResultNodes.data(), 924 MatchedGlueResultNodes.size())); 925 926 AddMatcher(new CompleteMatchMatcher(Ops.data(), Ops.size(), Pattern)); 927 } 928 929 930 /// ConvertPatternToMatcher - Create the matcher for the specified pattern with 931 /// the specified variant. If the variant number is invalid, this returns null. 932 Matcher *llvm::ConvertPatternToMatcher(const PatternToMatch &Pattern, 933 unsigned Variant, 934 const CodeGenDAGPatterns &CGP) { 935 MatcherGen Gen(Pattern, CGP); 936 937 // Generate the code for the matcher. 938 if (Gen.EmitMatcherCode(Variant)) 939 return 0; 940 941 // FIXME2: Kill extra MoveParent commands at the end of the matcher sequence. 942 // FIXME2: Split result code out to another table, and make the matcher end 943 // with an "Emit <index>" command. This allows result generation stuff to be 944 // shared and factored? 945 946 // If the match succeeds, then we generate Pattern. 947 Gen.EmitResultCode(); 948 949 // Unconditional match. 950 return Gen.GetMatcher(); 951 } 952