1 //===-- LegalizeTypes.cpp - Common code for DAG type legalizer ------------===// 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 // This file implements the SelectionDAG::LegalizeTypes method. It transforms 11 // an arbitrary well-formed SelectionDAG to only consist of legal types. This 12 // is common code shared among the LegalizeTypes*.cpp files. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #include "LegalizeTypes.h" 17 #include "llvm/CallingConv.h" 18 #include "llvm/Target/TargetData.h" 19 #include "llvm/ADT/SetVector.h" 20 #include "llvm/Support/CommandLine.h" 21 #include "llvm/Support/ErrorHandling.h" 22 #include "llvm/Support/raw_ostream.h" 23 using namespace llvm; 24 25 static cl::opt<bool> 26 EnableExpensiveChecks("enable-legalize-types-checking", cl::Hidden); 27 28 /// PerformExpensiveChecks - Do extensive, expensive, sanity checking. 29 void DAGTypeLegalizer::PerformExpensiveChecks() { 30 // If a node is not processed, then none of its values should be mapped by any 31 // of PromotedIntegers, ExpandedIntegers, ..., ReplacedValues. 32 33 // If a node is processed, then each value with an illegal type must be mapped 34 // by exactly one of PromotedIntegers, ExpandedIntegers, ..., ReplacedValues. 35 // Values with a legal type may be mapped by ReplacedValues, but not by any of 36 // the other maps. 37 38 // Note that these invariants may not hold momentarily when processing a node: 39 // the node being processed may be put in a map before being marked Processed. 40 41 // Note that it is possible to have nodes marked NewNode in the DAG. This can 42 // occur in two ways. Firstly, a node may be created during legalization but 43 // never passed to the legalization core. This is usually due to the implicit 44 // folding that occurs when using the DAG.getNode operators. Secondly, a new 45 // node may be passed to the legalization core, but when analyzed may morph 46 // into a different node, leaving the original node as a NewNode in the DAG. 47 // A node may morph if one of its operands changes during analysis. Whether 48 // it actually morphs or not depends on whether, after updating its operands, 49 // it is equivalent to an existing node: if so, it morphs into that existing 50 // node (CSE). An operand can change during analysis if the operand is a new 51 // node that morphs, or it is a processed value that was mapped to some other 52 // value (as recorded in ReplacedValues) in which case the operand is turned 53 // into that other value. If a node morphs then the node it morphed into will 54 // be used instead of it for legalization, however the original node continues 55 // to live on in the DAG. 56 // The conclusion is that though there may be nodes marked NewNode in the DAG, 57 // all uses of such nodes are also marked NewNode: the result is a fungus of 58 // NewNodes growing on top of the useful nodes, and perhaps using them, but 59 // not used by them. 60 61 // If a value is mapped by ReplacedValues, then it must have no uses, except 62 // by nodes marked NewNode (see above). 63 64 // The final node obtained by mapping by ReplacedValues is not marked NewNode. 65 // Note that ReplacedValues should be applied iteratively. 66 67 // Note that the ReplacedValues map may also map deleted nodes (by iterating 68 // over the DAG we never dereference deleted nodes). This means that it may 69 // also map nodes marked NewNode if the deallocated memory was reallocated as 70 // another node, and that new node was not seen by the LegalizeTypes machinery 71 // (for example because it was created but not used). In general, we cannot 72 // distinguish between new nodes and deleted nodes. 73 SmallVector<SDNode*, 16> NewNodes; 74 for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(), 75 E = DAG.allnodes_end(); I != E; ++I) { 76 // Remember nodes marked NewNode - they are subject to extra checking below. 77 if (I->getNodeId() == NewNode) 78 NewNodes.push_back(I); 79 80 for (unsigned i = 0, e = I->getNumValues(); i != e; ++i) { 81 SDValue Res(I, i); 82 bool Failed = false; 83 84 unsigned Mapped = 0; 85 if (ReplacedValues.find(Res) != ReplacedValues.end()) { 86 Mapped |= 1; 87 // Check that remapped values are only used by nodes marked NewNode. 88 for (SDNode::use_iterator UI = I->use_begin(), UE = I->use_end(); 89 UI != UE; ++UI) 90 if (UI.getUse().getResNo() == i) 91 assert(UI->getNodeId() == NewNode && 92 "Remapped value has non-trivial use!"); 93 94 // Check that the final result of applying ReplacedValues is not 95 // marked NewNode. 96 SDValue NewVal = ReplacedValues[Res]; 97 DenseMap<SDValue, SDValue>::iterator I = ReplacedValues.find(NewVal); 98 while (I != ReplacedValues.end()) { 99 NewVal = I->second; 100 I = ReplacedValues.find(NewVal); 101 } 102 assert(NewVal.getNode()->getNodeId() != NewNode && 103 "ReplacedValues maps to a new node!"); 104 } 105 if (PromotedIntegers.find(Res) != PromotedIntegers.end()) 106 Mapped |= 2; 107 if (SoftenedFloats.find(Res) != SoftenedFloats.end()) 108 Mapped |= 4; 109 if (ScalarizedVectors.find(Res) != ScalarizedVectors.end()) 110 Mapped |= 8; 111 if (ExpandedIntegers.find(Res) != ExpandedIntegers.end()) 112 Mapped |= 16; 113 if (ExpandedFloats.find(Res) != ExpandedFloats.end()) 114 Mapped |= 32; 115 if (SplitVectors.find(Res) != SplitVectors.end()) 116 Mapped |= 64; 117 if (WidenedVectors.find(Res) != WidenedVectors.end()) 118 Mapped |= 128; 119 120 if (I->getNodeId() != Processed) { 121 // Since we allow ReplacedValues to map deleted nodes, it may map nodes 122 // marked NewNode too, since a deleted node may have been reallocated as 123 // another node that has not been seen by the LegalizeTypes machinery. 124 if ((I->getNodeId() == NewNode && Mapped > 1) || 125 (I->getNodeId() != NewNode && Mapped != 0)) { 126 dbgs() << "Unprocessed value in a map!"; 127 Failed = true; 128 } 129 } else if (isTypeLegal(Res.getValueType()) || IgnoreNodeResults(I)) { 130 if (Mapped > 1) { 131 dbgs() << "Value with legal type was transformed!"; 132 Failed = true; 133 } 134 } else { 135 if (Mapped == 0) { 136 dbgs() << "Processed value not in any map!"; 137 Failed = true; 138 } else if (Mapped & (Mapped - 1)) { 139 dbgs() << "Value in multiple maps!"; 140 Failed = true; 141 } 142 } 143 144 if (Failed) { 145 if (Mapped & 1) 146 dbgs() << " ReplacedValues"; 147 if (Mapped & 2) 148 dbgs() << " PromotedIntegers"; 149 if (Mapped & 4) 150 dbgs() << " SoftenedFloats"; 151 if (Mapped & 8) 152 dbgs() << " ScalarizedVectors"; 153 if (Mapped & 16) 154 dbgs() << " ExpandedIntegers"; 155 if (Mapped & 32) 156 dbgs() << " ExpandedFloats"; 157 if (Mapped & 64) 158 dbgs() << " SplitVectors"; 159 if (Mapped & 128) 160 dbgs() << " WidenedVectors"; 161 dbgs() << "\n"; 162 llvm_unreachable(0); 163 } 164 } 165 } 166 167 // Checked that NewNodes are only used by other NewNodes. 168 for (unsigned i = 0, e = NewNodes.size(); i != e; ++i) { 169 SDNode *N = NewNodes[i]; 170 for (SDNode::use_iterator UI = N->use_begin(), UE = N->use_end(); 171 UI != UE; ++UI) 172 assert(UI->getNodeId() == NewNode && "NewNode used by non-NewNode!"); 173 } 174 } 175 176 /// run - This is the main entry point for the type legalizer. This does a 177 /// top-down traversal of the dag, legalizing types as it goes. Returns "true" 178 /// if it made any changes. 179 bool DAGTypeLegalizer::run() { 180 bool Changed = false; 181 182 // Create a dummy node (which is not added to allnodes), that adds a reference 183 // to the root node, preventing it from being deleted, and tracking any 184 // changes of the root. 185 HandleSDNode Dummy(DAG.getRoot()); 186 Dummy.setNodeId(Unanalyzed); 187 188 // The root of the dag may dangle to deleted nodes until the type legalizer is 189 // done. Set it to null to avoid confusion. 190 DAG.setRoot(SDValue()); 191 192 // Walk all nodes in the graph, assigning them a NodeId of 'ReadyToProcess' 193 // (and remembering them) if they are leaves and assigning 'Unanalyzed' if 194 // non-leaves. 195 for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(), 196 E = DAG.allnodes_end(); I != E; ++I) { 197 if (I->getNumOperands() == 0) { 198 I->setNodeId(ReadyToProcess); 199 Worklist.push_back(I); 200 } else { 201 I->setNodeId(Unanalyzed); 202 } 203 } 204 205 // Now that we have a set of nodes to process, handle them all. 206 while (!Worklist.empty()) { 207 #ifndef XDEBUG 208 if (EnableExpensiveChecks) 209 #endif 210 PerformExpensiveChecks(); 211 212 SDNode *N = Worklist.back(); 213 Worklist.pop_back(); 214 assert(N->getNodeId() == ReadyToProcess && 215 "Node should be ready if on worklist!"); 216 217 if (IgnoreNodeResults(N)) 218 goto ScanOperands; 219 220 // Scan the values produced by the node, checking to see if any result 221 // types are illegal. 222 for (unsigned i = 0, NumResults = N->getNumValues(); i < NumResults; ++i) { 223 EVT ResultVT = N->getValueType(i); 224 switch (getTypeAction(ResultVT)) { 225 case TargetLowering::TypeLegal: 226 break; 227 // The following calls must take care of *all* of the node's results, 228 // not just the illegal result they were passed (this includes results 229 // with a legal type). Results can be remapped using ReplaceValueWith, 230 // or their promoted/expanded/etc values registered in PromotedIntegers, 231 // ExpandedIntegers etc. 232 case TargetLowering::TypePromoteInteger: 233 PromoteIntegerResult(N, i); 234 Changed = true; 235 goto NodeDone; 236 case TargetLowering::TypeExpandInteger: 237 ExpandIntegerResult(N, i); 238 Changed = true; 239 goto NodeDone; 240 case TargetLowering::TypeSoftenFloat: 241 SoftenFloatResult(N, i); 242 Changed = true; 243 goto NodeDone; 244 case TargetLowering::TypeExpandFloat: 245 ExpandFloatResult(N, i); 246 Changed = true; 247 goto NodeDone; 248 case TargetLowering::TypeScalarizeVector: 249 ScalarizeVectorResult(N, i); 250 Changed = true; 251 goto NodeDone; 252 case TargetLowering::TypeSplitVector: 253 SplitVectorResult(N, i); 254 Changed = true; 255 goto NodeDone; 256 case TargetLowering::TypeWidenVector: 257 WidenVectorResult(N, i); 258 Changed = true; 259 goto NodeDone; 260 } 261 } 262 263 ScanOperands: 264 // Scan the operand list for the node, handling any nodes with operands that 265 // are illegal. 266 { 267 unsigned NumOperands = N->getNumOperands(); 268 bool NeedsReanalyzing = false; 269 unsigned i; 270 for (i = 0; i != NumOperands; ++i) { 271 if (IgnoreNodeResults(N->getOperand(i).getNode())) 272 continue; 273 274 EVT OpVT = N->getOperand(i).getValueType(); 275 switch (getTypeAction(OpVT)) { 276 case TargetLowering::TypeLegal: 277 continue; 278 // The following calls must either replace all of the node's results 279 // using ReplaceValueWith, and return "false"; or update the node's 280 // operands in place, and return "true". 281 case TargetLowering::TypePromoteInteger: 282 NeedsReanalyzing = PromoteIntegerOperand(N, i); 283 Changed = true; 284 break; 285 case TargetLowering::TypeExpandInteger: 286 NeedsReanalyzing = ExpandIntegerOperand(N, i); 287 Changed = true; 288 break; 289 case TargetLowering::TypeSoftenFloat: 290 NeedsReanalyzing = SoftenFloatOperand(N, i); 291 Changed = true; 292 break; 293 case TargetLowering::TypeExpandFloat: 294 NeedsReanalyzing = ExpandFloatOperand(N, i); 295 Changed = true; 296 break; 297 case TargetLowering::TypeScalarizeVector: 298 NeedsReanalyzing = ScalarizeVectorOperand(N, i); 299 Changed = true; 300 break; 301 case TargetLowering::TypeSplitVector: 302 NeedsReanalyzing = SplitVectorOperand(N, i); 303 Changed = true; 304 break; 305 case TargetLowering::TypeWidenVector: 306 NeedsReanalyzing = WidenVectorOperand(N, i); 307 Changed = true; 308 break; 309 } 310 break; 311 } 312 313 // The sub-method updated N in place. Check to see if any operands are new, 314 // and if so, mark them. If the node needs revisiting, don't add all users 315 // to the worklist etc. 316 if (NeedsReanalyzing) { 317 assert(N->getNodeId() == ReadyToProcess && "Node ID recalculated?"); 318 N->setNodeId(NewNode); 319 // Recompute the NodeId and correct processed operands, adding the node to 320 // the worklist if ready. 321 SDNode *M = AnalyzeNewNode(N); 322 if (M == N) 323 // The node didn't morph - nothing special to do, it will be revisited. 324 continue; 325 326 // The node morphed - this is equivalent to legalizing by replacing every 327 // value of N with the corresponding value of M. So do that now. 328 assert(N->getNumValues() == M->getNumValues() && 329 "Node morphing changed the number of results!"); 330 for (unsigned i = 0, e = N->getNumValues(); i != e; ++i) 331 // Replacing the value takes care of remapping the new value. 332 ReplaceValueWith(SDValue(N, i), SDValue(M, i)); 333 assert(N->getNodeId() == NewNode && "Unexpected node state!"); 334 // The node continues to live on as part of the NewNode fungus that 335 // grows on top of the useful nodes. Nothing more needs to be done 336 // with it - move on to the next node. 337 continue; 338 } 339 340 if (i == NumOperands) { 341 DEBUG(dbgs() << "Legally typed node: "; N->dump(&DAG); dbgs() << "\n"); 342 } 343 } 344 NodeDone: 345 346 // If we reach here, the node was processed, potentially creating new nodes. 347 // Mark it as processed and add its users to the worklist as appropriate. 348 assert(N->getNodeId() == ReadyToProcess && "Node ID recalculated?"); 349 N->setNodeId(Processed); 350 351 for (SDNode::use_iterator UI = N->use_begin(), E = N->use_end(); 352 UI != E; ++UI) { 353 SDNode *User = *UI; 354 int NodeId = User->getNodeId(); 355 356 // This node has two options: it can either be a new node or its Node ID 357 // may be a count of the number of operands it has that are not ready. 358 if (NodeId > 0) { 359 User->setNodeId(NodeId-1); 360 361 // If this was the last use it was waiting on, add it to the ready list. 362 if (NodeId-1 == ReadyToProcess) 363 Worklist.push_back(User); 364 continue; 365 } 366 367 // If this is an unreachable new node, then ignore it. If it ever becomes 368 // reachable by being used by a newly created node then it will be handled 369 // by AnalyzeNewNode. 370 if (NodeId == NewNode) 371 continue; 372 373 // Otherwise, this node is new: this is the first operand of it that 374 // became ready. Its new NodeId is the number of operands it has minus 1 375 // (as this node is now processed). 376 assert(NodeId == Unanalyzed && "Unknown node ID!"); 377 User->setNodeId(User->getNumOperands() - 1); 378 379 // If the node only has a single operand, it is now ready. 380 if (User->getNumOperands() == 1) 381 Worklist.push_back(User); 382 } 383 } 384 385 #ifndef XDEBUG 386 if (EnableExpensiveChecks) 387 #endif 388 PerformExpensiveChecks(); 389 390 // If the root changed (e.g. it was a dead load) update the root. 391 DAG.setRoot(Dummy.getValue()); 392 393 // Remove dead nodes. This is important to do for cleanliness but also before 394 // the checking loop below. Implicit folding by the DAG.getNode operators and 395 // node morphing can cause unreachable nodes to be around with their flags set 396 // to new. 397 DAG.RemoveDeadNodes(); 398 399 // In a debug build, scan all the nodes to make sure we found them all. This 400 // ensures that there are no cycles and that everything got processed. 401 #ifndef NDEBUG 402 for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(), 403 E = DAG.allnodes_end(); I != E; ++I) { 404 bool Failed = false; 405 406 // Check that all result types are legal. 407 if (!IgnoreNodeResults(I)) 408 for (unsigned i = 0, NumVals = I->getNumValues(); i < NumVals; ++i) 409 if (!isTypeLegal(I->getValueType(i))) { 410 dbgs() << "Result type " << i << " illegal!\n"; 411 Failed = true; 412 } 413 414 // Check that all operand types are legal. 415 for (unsigned i = 0, NumOps = I->getNumOperands(); i < NumOps; ++i) 416 if (!IgnoreNodeResults(I->getOperand(i).getNode()) && 417 !isTypeLegal(I->getOperand(i).getValueType())) { 418 dbgs() << "Operand type " << i << " illegal!\n"; 419 Failed = true; 420 } 421 422 if (I->getNodeId() != Processed) { 423 if (I->getNodeId() == NewNode) 424 dbgs() << "New node not analyzed?\n"; 425 else if (I->getNodeId() == Unanalyzed) 426 dbgs() << "Unanalyzed node not noticed?\n"; 427 else if (I->getNodeId() > 0) 428 dbgs() << "Operand not processed?\n"; 429 else if (I->getNodeId() == ReadyToProcess) 430 dbgs() << "Not added to worklist?\n"; 431 Failed = true; 432 } 433 434 if (Failed) { 435 I->dump(&DAG); dbgs() << "\n"; 436 llvm_unreachable(0); 437 } 438 } 439 #endif 440 441 return Changed; 442 } 443 444 /// AnalyzeNewNode - The specified node is the root of a subtree of potentially 445 /// new nodes. Correct any processed operands (this may change the node) and 446 /// calculate the NodeId. If the node itself changes to a processed node, it 447 /// is not remapped - the caller needs to take care of this. 448 /// Returns the potentially changed node. 449 SDNode *DAGTypeLegalizer::AnalyzeNewNode(SDNode *N) { 450 // If this was an existing node that is already done, we're done. 451 if (N->getNodeId() != NewNode && N->getNodeId() != Unanalyzed) 452 return N; 453 454 // Remove any stale map entries. 455 ExpungeNode(N); 456 457 // Okay, we know that this node is new. Recursively walk all of its operands 458 // to see if they are new also. The depth of this walk is bounded by the size 459 // of the new tree that was constructed (usually 2-3 nodes), so we don't worry 460 // about revisiting of nodes. 461 // 462 // As we walk the operands, keep track of the number of nodes that are 463 // processed. If non-zero, this will become the new nodeid of this node. 464 // Operands may morph when they are analyzed. If so, the node will be 465 // updated after all operands have been analyzed. Since this is rare, 466 // the code tries to minimize overhead in the non-morphing case. 467 468 SmallVector<SDValue, 8> NewOps; 469 unsigned NumProcessed = 0; 470 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) { 471 SDValue OrigOp = N->getOperand(i); 472 SDValue Op = OrigOp; 473 474 AnalyzeNewValue(Op); // Op may morph. 475 476 if (Op.getNode()->getNodeId() == Processed) 477 ++NumProcessed; 478 479 if (!NewOps.empty()) { 480 // Some previous operand changed. Add this one to the list. 481 NewOps.push_back(Op); 482 } else if (Op != OrigOp) { 483 // This is the first operand to change - add all operands so far. 484 NewOps.append(N->op_begin(), N->op_begin() + i); 485 NewOps.push_back(Op); 486 } 487 } 488 489 // Some operands changed - update the node. 490 if (!NewOps.empty()) { 491 SDNode *M = DAG.UpdateNodeOperands(N, &NewOps[0], NewOps.size()); 492 if (M != N) { 493 // The node morphed into a different node. Normally for this to happen 494 // the original node would have to be marked NewNode. However this can 495 // in theory momentarily not be the case while ReplaceValueWith is doing 496 // its stuff. Mark the original node NewNode to help sanity checking. 497 N->setNodeId(NewNode); 498 if (M->getNodeId() != NewNode && M->getNodeId() != Unanalyzed) 499 // It morphed into a previously analyzed node - nothing more to do. 500 return M; 501 502 // It morphed into a different new node. Do the equivalent of passing 503 // it to AnalyzeNewNode: expunge it and calculate the NodeId. No need 504 // to remap the operands, since they are the same as the operands we 505 // remapped above. 506 N = M; 507 ExpungeNode(N); 508 } 509 } 510 511 // Calculate the NodeId. 512 N->setNodeId(N->getNumOperands() - NumProcessed); 513 if (N->getNodeId() == ReadyToProcess) 514 Worklist.push_back(N); 515 516 return N; 517 } 518 519 /// AnalyzeNewValue - Call AnalyzeNewNode, updating the node in Val if needed. 520 /// If the node changes to a processed node, then remap it. 521 void DAGTypeLegalizer::AnalyzeNewValue(SDValue &Val) { 522 Val.setNode(AnalyzeNewNode(Val.getNode())); 523 if (Val.getNode()->getNodeId() == Processed) 524 // We were passed a processed node, or it morphed into one - remap it. 525 RemapValue(Val); 526 } 527 528 /// ExpungeNode - If N has a bogus mapping in ReplacedValues, eliminate it. 529 /// This can occur when a node is deleted then reallocated as a new node - 530 /// the mapping in ReplacedValues applies to the deleted node, not the new 531 /// one. 532 /// The only map that can have a deleted node as a source is ReplacedValues. 533 /// Other maps can have deleted nodes as targets, but since their looked-up 534 /// values are always immediately remapped using RemapValue, resulting in a 535 /// not-deleted node, this is harmless as long as ReplacedValues/RemapValue 536 /// always performs correct mappings. In order to keep the mapping correct, 537 /// ExpungeNode should be called on any new nodes *before* adding them as 538 /// either source or target to ReplacedValues (which typically means calling 539 /// Expunge when a new node is first seen, since it may no longer be marked 540 /// NewNode by the time it is added to ReplacedValues). 541 void DAGTypeLegalizer::ExpungeNode(SDNode *N) { 542 if (N->getNodeId() != NewNode) 543 return; 544 545 // If N is not remapped by ReplacedValues then there is nothing to do. 546 unsigned i, e; 547 for (i = 0, e = N->getNumValues(); i != e; ++i) 548 if (ReplacedValues.find(SDValue(N, i)) != ReplacedValues.end()) 549 break; 550 551 if (i == e) 552 return; 553 554 // Remove N from all maps - this is expensive but rare. 555 556 for (DenseMap<SDValue, SDValue>::iterator I = PromotedIntegers.begin(), 557 E = PromotedIntegers.end(); I != E; ++I) { 558 assert(I->first.getNode() != N); 559 RemapValue(I->second); 560 } 561 562 for (DenseMap<SDValue, SDValue>::iterator I = SoftenedFloats.begin(), 563 E = SoftenedFloats.end(); I != E; ++I) { 564 assert(I->first.getNode() != N); 565 RemapValue(I->second); 566 } 567 568 for (DenseMap<SDValue, SDValue>::iterator I = ScalarizedVectors.begin(), 569 E = ScalarizedVectors.end(); I != E; ++I) { 570 assert(I->first.getNode() != N); 571 RemapValue(I->second); 572 } 573 574 for (DenseMap<SDValue, SDValue>::iterator I = WidenedVectors.begin(), 575 E = WidenedVectors.end(); I != E; ++I) { 576 assert(I->first.getNode() != N); 577 RemapValue(I->second); 578 } 579 580 for (DenseMap<SDValue, std::pair<SDValue, SDValue> >::iterator 581 I = ExpandedIntegers.begin(), E = ExpandedIntegers.end(); I != E; ++I){ 582 assert(I->first.getNode() != N); 583 RemapValue(I->second.first); 584 RemapValue(I->second.second); 585 } 586 587 for (DenseMap<SDValue, std::pair<SDValue, SDValue> >::iterator 588 I = ExpandedFloats.begin(), E = ExpandedFloats.end(); I != E; ++I) { 589 assert(I->first.getNode() != N); 590 RemapValue(I->second.first); 591 RemapValue(I->second.second); 592 } 593 594 for (DenseMap<SDValue, std::pair<SDValue, SDValue> >::iterator 595 I = SplitVectors.begin(), E = SplitVectors.end(); I != E; ++I) { 596 assert(I->first.getNode() != N); 597 RemapValue(I->second.first); 598 RemapValue(I->second.second); 599 } 600 601 for (DenseMap<SDValue, SDValue>::iterator I = ReplacedValues.begin(), 602 E = ReplacedValues.end(); I != E; ++I) 603 RemapValue(I->second); 604 605 for (unsigned i = 0, e = N->getNumValues(); i != e; ++i) 606 ReplacedValues.erase(SDValue(N, i)); 607 } 608 609 /// RemapValue - If the specified value was already legalized to another value, 610 /// replace it by that value. 611 void DAGTypeLegalizer::RemapValue(SDValue &N) { 612 DenseMap<SDValue, SDValue>::iterator I = ReplacedValues.find(N); 613 if (I != ReplacedValues.end()) { 614 // Use path compression to speed up future lookups if values get multiply 615 // replaced with other values. 616 RemapValue(I->second); 617 N = I->second; 618 assert(N.getNode()->getNodeId() != NewNode && "Mapped to new node!"); 619 } 620 } 621 622 namespace { 623 /// NodeUpdateListener - This class is a DAGUpdateListener that listens for 624 /// updates to nodes and recomputes their ready state. 625 class NodeUpdateListener : public SelectionDAG::DAGUpdateListener { 626 DAGTypeLegalizer &DTL; 627 SmallSetVector<SDNode*, 16> &NodesToAnalyze; 628 public: 629 explicit NodeUpdateListener(DAGTypeLegalizer &dtl, 630 SmallSetVector<SDNode*, 16> &nta) 631 : DTL(dtl), NodesToAnalyze(nta) {} 632 633 virtual void NodeDeleted(SDNode *N, SDNode *E) { 634 assert(N->getNodeId() != DAGTypeLegalizer::ReadyToProcess && 635 N->getNodeId() != DAGTypeLegalizer::Processed && 636 "Invalid node ID for RAUW deletion!"); 637 // It is possible, though rare, for the deleted node N to occur as a 638 // target in a map, so note the replacement N -> E in ReplacedValues. 639 assert(E && "Node not replaced?"); 640 DTL.NoteDeletion(N, E); 641 642 // In theory the deleted node could also have been scheduled for analysis. 643 // So remove it from the set of nodes which will be analyzed. 644 NodesToAnalyze.remove(N); 645 646 // In general nothing needs to be done for E, since it didn't change but 647 // only gained new uses. However N -> E was just added to ReplacedValues, 648 // and the result of a ReplacedValues mapping is not allowed to be marked 649 // NewNode. So if E is marked NewNode, then it needs to be analyzed. 650 if (E->getNodeId() == DAGTypeLegalizer::NewNode) 651 NodesToAnalyze.insert(E); 652 } 653 654 virtual void NodeUpdated(SDNode *N) { 655 // Node updates can mean pretty much anything. It is possible that an 656 // operand was set to something already processed (f.e.) in which case 657 // this node could become ready. Recompute its flags. 658 assert(N->getNodeId() != DAGTypeLegalizer::ReadyToProcess && 659 N->getNodeId() != DAGTypeLegalizer::Processed && 660 "Invalid node ID for RAUW deletion!"); 661 N->setNodeId(DAGTypeLegalizer::NewNode); 662 NodesToAnalyze.insert(N); 663 } 664 }; 665 } 666 667 668 /// ReplaceValueWith - The specified value was legalized to the specified other 669 /// value. Update the DAG and NodeIds replacing any uses of From to use To 670 /// instead. 671 void DAGTypeLegalizer::ReplaceValueWith(SDValue From, SDValue To) { 672 assert(From.getNode() != To.getNode() && "Potential legalization loop!"); 673 674 // If expansion produced new nodes, make sure they are properly marked. 675 ExpungeNode(From.getNode()); 676 AnalyzeNewValue(To); // Expunges To. 677 678 // Anything that used the old node should now use the new one. Note that this 679 // can potentially cause recursive merging. 680 SmallSetVector<SDNode*, 16> NodesToAnalyze; 681 NodeUpdateListener NUL(*this, NodesToAnalyze); 682 do { 683 DAG.ReplaceAllUsesOfValueWith(From, To, &NUL); 684 685 // The old node may still be present in a map like ExpandedIntegers or 686 // PromotedIntegers. Inform maps about the replacement. 687 ReplacedValues[From] = To; 688 689 // Process the list of nodes that need to be reanalyzed. 690 while (!NodesToAnalyze.empty()) { 691 SDNode *N = NodesToAnalyze.back(); 692 NodesToAnalyze.pop_back(); 693 if (N->getNodeId() != DAGTypeLegalizer::NewNode) 694 // The node was analyzed while reanalyzing an earlier node - it is safe 695 // to skip. Note that this is not a morphing node - otherwise it would 696 // still be marked NewNode. 697 continue; 698 699 // Analyze the node's operands and recalculate the node ID. 700 SDNode *M = AnalyzeNewNode(N); 701 if (M != N) { 702 // The node morphed into a different node. Make everyone use the new 703 // node instead. 704 assert(M->getNodeId() != NewNode && "Analysis resulted in NewNode!"); 705 assert(N->getNumValues() == M->getNumValues() && 706 "Node morphing changed the number of results!"); 707 for (unsigned i = 0, e = N->getNumValues(); i != e; ++i) { 708 SDValue OldVal(N, i); 709 SDValue NewVal(M, i); 710 if (M->getNodeId() == Processed) 711 RemapValue(NewVal); 712 DAG.ReplaceAllUsesOfValueWith(OldVal, NewVal, &NUL); 713 // OldVal may be a target of the ReplacedValues map which was marked 714 // NewNode to force reanalysis because it was updated. Ensure that 715 // anything that ReplacedValues mapped to OldVal will now be mapped 716 // all the way to NewVal. 717 ReplacedValues[OldVal] = NewVal; 718 } 719 // The original node continues to exist in the DAG, marked NewNode. 720 } 721 } 722 // When recursively update nodes with new nodes, it is possible to have 723 // new uses of From due to CSE. If this happens, replace the new uses of 724 // From with To. 725 } while (!From.use_empty()); 726 } 727 728 void DAGTypeLegalizer::SetPromotedInteger(SDValue Op, SDValue Result) { 729 assert(Result.getValueType() == 730 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType()) && 731 "Invalid type for promoted integer"); 732 AnalyzeNewValue(Result); 733 734 SDValue &OpEntry = PromotedIntegers[Op]; 735 assert(OpEntry.getNode() == 0 && "Node is already promoted!"); 736 OpEntry = Result; 737 } 738 739 void DAGTypeLegalizer::SetSoftenedFloat(SDValue Op, SDValue Result) { 740 assert(Result.getValueType() == 741 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType()) && 742 "Invalid type for softened float"); 743 AnalyzeNewValue(Result); 744 745 SDValue &OpEntry = SoftenedFloats[Op]; 746 assert(OpEntry.getNode() == 0 && "Node is already converted to integer!"); 747 OpEntry = Result; 748 } 749 750 void DAGTypeLegalizer::SetScalarizedVector(SDValue Op, SDValue Result) { 751 // Note that in some cases vector operation operands may be greater than 752 // the vector element type. For example BUILD_VECTOR of type <1 x i1> with 753 // a constant i8 operand. 754 assert(Result.getValueType().getSizeInBits() >= 755 Op.getValueType().getVectorElementType().getSizeInBits() && 756 "Invalid type for scalarized vector"); 757 AnalyzeNewValue(Result); 758 759 SDValue &OpEntry = ScalarizedVectors[Op]; 760 assert(OpEntry.getNode() == 0 && "Node is already scalarized!"); 761 OpEntry = Result; 762 } 763 764 void DAGTypeLegalizer::GetExpandedInteger(SDValue Op, SDValue &Lo, 765 SDValue &Hi) { 766 std::pair<SDValue, SDValue> &Entry = ExpandedIntegers[Op]; 767 RemapValue(Entry.first); 768 RemapValue(Entry.second); 769 assert(Entry.first.getNode() && "Operand isn't expanded"); 770 Lo = Entry.first; 771 Hi = Entry.second; 772 } 773 774 void DAGTypeLegalizer::SetExpandedInteger(SDValue Op, SDValue Lo, 775 SDValue Hi) { 776 assert(Lo.getValueType() == 777 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType()) && 778 Hi.getValueType() == Lo.getValueType() && 779 "Invalid type for expanded integer"); 780 // Lo/Hi may have been newly allocated, if so, add nodeid's as relevant. 781 AnalyzeNewValue(Lo); 782 AnalyzeNewValue(Hi); 783 784 // Remember that this is the result of the node. 785 std::pair<SDValue, SDValue> &Entry = ExpandedIntegers[Op]; 786 assert(Entry.first.getNode() == 0 && "Node already expanded"); 787 Entry.first = Lo; 788 Entry.second = Hi; 789 } 790 791 void DAGTypeLegalizer::GetExpandedFloat(SDValue Op, SDValue &Lo, 792 SDValue &Hi) { 793 std::pair<SDValue, SDValue> &Entry = ExpandedFloats[Op]; 794 RemapValue(Entry.first); 795 RemapValue(Entry.second); 796 assert(Entry.first.getNode() && "Operand isn't expanded"); 797 Lo = Entry.first; 798 Hi = Entry.second; 799 } 800 801 void DAGTypeLegalizer::SetExpandedFloat(SDValue Op, SDValue Lo, 802 SDValue Hi) { 803 assert(Lo.getValueType() == 804 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType()) && 805 Hi.getValueType() == Lo.getValueType() && 806 "Invalid type for expanded float"); 807 // Lo/Hi may have been newly allocated, if so, add nodeid's as relevant. 808 AnalyzeNewValue(Lo); 809 AnalyzeNewValue(Hi); 810 811 // Remember that this is the result of the node. 812 std::pair<SDValue, SDValue> &Entry = ExpandedFloats[Op]; 813 assert(Entry.first.getNode() == 0 && "Node already expanded"); 814 Entry.first = Lo; 815 Entry.second = Hi; 816 } 817 818 void DAGTypeLegalizer::GetSplitVector(SDValue Op, SDValue &Lo, 819 SDValue &Hi) { 820 std::pair<SDValue, SDValue> &Entry = SplitVectors[Op]; 821 RemapValue(Entry.first); 822 RemapValue(Entry.second); 823 assert(Entry.first.getNode() && "Operand isn't split"); 824 Lo = Entry.first; 825 Hi = Entry.second; 826 } 827 828 void DAGTypeLegalizer::SetSplitVector(SDValue Op, SDValue Lo, 829 SDValue Hi) { 830 assert(Lo.getValueType().getVectorElementType() == 831 Op.getValueType().getVectorElementType() && 832 2*Lo.getValueType().getVectorNumElements() == 833 Op.getValueType().getVectorNumElements() && 834 Hi.getValueType() == Lo.getValueType() && 835 "Invalid type for split vector"); 836 // Lo/Hi may have been newly allocated, if so, add nodeid's as relevant. 837 AnalyzeNewValue(Lo); 838 AnalyzeNewValue(Hi); 839 840 // Remember that this is the result of the node. 841 std::pair<SDValue, SDValue> &Entry = SplitVectors[Op]; 842 assert(Entry.first.getNode() == 0 && "Node already split"); 843 Entry.first = Lo; 844 Entry.second = Hi; 845 } 846 847 void DAGTypeLegalizer::SetWidenedVector(SDValue Op, SDValue Result) { 848 assert(Result.getValueType() == 849 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType()) && 850 "Invalid type for widened vector"); 851 AnalyzeNewValue(Result); 852 853 SDValue &OpEntry = WidenedVectors[Op]; 854 assert(OpEntry.getNode() == 0 && "Node already widened!"); 855 OpEntry = Result; 856 } 857 858 859 //===----------------------------------------------------------------------===// 860 // Utilities. 861 //===----------------------------------------------------------------------===// 862 863 /// BitConvertToInteger - Convert to an integer of the same size. 864 SDValue DAGTypeLegalizer::BitConvertToInteger(SDValue Op) { 865 unsigned BitWidth = Op.getValueType().getSizeInBits(); 866 return DAG.getNode(ISD::BITCAST, Op.getDebugLoc(), 867 EVT::getIntegerVT(*DAG.getContext(), BitWidth), Op); 868 } 869 870 /// BitConvertVectorToIntegerVector - Convert to a vector of integers of the 871 /// same size. 872 SDValue DAGTypeLegalizer::BitConvertVectorToIntegerVector(SDValue Op) { 873 assert(Op.getValueType().isVector() && "Only applies to vectors!"); 874 unsigned EltWidth = Op.getValueType().getVectorElementType().getSizeInBits(); 875 EVT EltNVT = EVT::getIntegerVT(*DAG.getContext(), EltWidth); 876 unsigned NumElts = Op.getValueType().getVectorNumElements(); 877 return DAG.getNode(ISD::BITCAST, Op.getDebugLoc(), 878 EVT::getVectorVT(*DAG.getContext(), EltNVT, NumElts), Op); 879 } 880 881 SDValue DAGTypeLegalizer::CreateStackStoreLoad(SDValue Op, 882 EVT DestVT) { 883 DebugLoc dl = Op.getDebugLoc(); 884 // Create the stack frame object. Make sure it is aligned for both 885 // the source and destination types. 886 SDValue StackPtr = DAG.CreateStackTemporary(Op.getValueType(), DestVT); 887 // Emit a store to the stack slot. 888 SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, Op, StackPtr, 889 MachinePointerInfo(), false, false, 0); 890 // Result is a load from the stack slot. 891 return DAG.getLoad(DestVT, dl, Store, StackPtr, MachinePointerInfo(), 892 false, false, false, 0); 893 } 894 895 /// CustomLowerNode - Replace the node's results with custom code provided 896 /// by the target and return "true", or do nothing and return "false". 897 /// The last parameter is FALSE if we are dealing with a node with legal 898 /// result types and illegal operand. The second parameter denotes the type of 899 /// illegal OperandNo in that case. 900 /// The last parameter being TRUE means we are dealing with a 901 /// node with illegal result types. The second parameter denotes the type of 902 /// illegal ResNo in that case. 903 bool DAGTypeLegalizer::CustomLowerNode(SDNode *N, EVT VT, bool LegalizeResult) { 904 // See if the target wants to custom lower this node. 905 if (TLI.getOperationAction(N->getOpcode(), VT) != TargetLowering::Custom) 906 return false; 907 908 SmallVector<SDValue, 8> Results; 909 if (LegalizeResult) 910 TLI.ReplaceNodeResults(N, Results, DAG); 911 else 912 TLI.LowerOperationWrapper(N, Results, DAG); 913 914 if (Results.empty()) 915 // The target didn't want to custom lower it after all. 916 return false; 917 918 // Make everything that once used N's values now use those in Results instead. 919 assert(Results.size() == N->getNumValues() && 920 "Custom lowering returned the wrong number of results!"); 921 for (unsigned i = 0, e = Results.size(); i != e; ++i) 922 ReplaceValueWith(SDValue(N, i), Results[i]); 923 return true; 924 } 925 926 927 /// CustomWidenLowerNode - Widen the node's results with custom code provided 928 /// by the target and return "true", or do nothing and return "false". 929 bool DAGTypeLegalizer::CustomWidenLowerNode(SDNode *N, EVT VT) { 930 // See if the target wants to custom lower this node. 931 if (TLI.getOperationAction(N->getOpcode(), VT) != TargetLowering::Custom) 932 return false; 933 934 SmallVector<SDValue, 8> Results; 935 TLI.ReplaceNodeResults(N, Results, DAG); 936 937 if (Results.empty()) 938 // The target didn't want to custom widen lower its result after all. 939 return false; 940 941 // Update the widening map. 942 assert(Results.size() == N->getNumValues() && 943 "Custom lowering returned the wrong number of results!"); 944 for (unsigned i = 0, e = Results.size(); i != e; ++i) 945 SetWidenedVector(SDValue(N, i), Results[i]); 946 return true; 947 } 948 949 SDValue DAGTypeLegalizer::DisintegrateMERGE_VALUES(SDNode *N, unsigned ResNo) { 950 for (unsigned i = 0, e = N->getNumValues(); i != e; ++i) 951 if (i != ResNo) 952 ReplaceValueWith(SDValue(N, i), SDValue(N->getOperand(i))); 953 return SDValue(N, ResNo); 954 } 955 956 /// GetSplitDestVTs - Compute the VTs needed for the low/hi parts of a type 957 /// which is split into two not necessarily identical pieces. 958 void DAGTypeLegalizer::GetSplitDestVTs(EVT InVT, EVT &LoVT, EVT &HiVT) { 959 // Currently all types are split in half. 960 if (!InVT.isVector()) { 961 LoVT = HiVT = TLI.getTypeToTransformTo(*DAG.getContext(), InVT); 962 } else { 963 unsigned NumElements = InVT.getVectorNumElements(); 964 assert(!(NumElements & 1) && "Splitting vector, but not in half!"); 965 LoVT = HiVT = EVT::getVectorVT(*DAG.getContext(), 966 InVT.getVectorElementType(), NumElements/2); 967 } 968 } 969 970 /// GetPairElements - Use ISD::EXTRACT_ELEMENT nodes to extract the low and 971 /// high parts of the given value. 972 void DAGTypeLegalizer::GetPairElements(SDValue Pair, 973 SDValue &Lo, SDValue &Hi) { 974 DebugLoc dl = Pair.getDebugLoc(); 975 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), Pair.getValueType()); 976 Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, NVT, Pair, 977 DAG.getIntPtrConstant(0)); 978 Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, NVT, Pair, 979 DAG.getIntPtrConstant(1)); 980 } 981 982 SDValue DAGTypeLegalizer::GetVectorElementPointer(SDValue VecPtr, EVT EltVT, 983 SDValue Index) { 984 DebugLoc dl = Index.getDebugLoc(); 985 // Make sure the index type is big enough to compute in. 986 if (Index.getValueType().bitsGT(TLI.getPointerTy())) 987 Index = DAG.getNode(ISD::TRUNCATE, dl, TLI.getPointerTy(), Index); 988 else 989 Index = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Index); 990 991 // Calculate the element offset and add it to the pointer. 992 unsigned EltSize = EltVT.getSizeInBits() / 8; // FIXME: should be ABI size. 993 994 Index = DAG.getNode(ISD::MUL, dl, Index.getValueType(), Index, 995 DAG.getConstant(EltSize, Index.getValueType())); 996 return DAG.getNode(ISD::ADD, dl, Index.getValueType(), Index, VecPtr); 997 } 998 999 /// JoinIntegers - Build an integer with low bits Lo and high bits Hi. 1000 SDValue DAGTypeLegalizer::JoinIntegers(SDValue Lo, SDValue Hi) { 1001 // Arbitrarily use dlHi for result DebugLoc 1002 DebugLoc dlHi = Hi.getDebugLoc(); 1003 DebugLoc dlLo = Lo.getDebugLoc(); 1004 EVT LVT = Lo.getValueType(); 1005 EVT HVT = Hi.getValueType(); 1006 EVT NVT = EVT::getIntegerVT(*DAG.getContext(), 1007 LVT.getSizeInBits() + HVT.getSizeInBits()); 1008 1009 Lo = DAG.getNode(ISD::ZERO_EXTEND, dlLo, NVT, Lo); 1010 Hi = DAG.getNode(ISD::ANY_EXTEND, dlHi, NVT, Hi); 1011 Hi = DAG.getNode(ISD::SHL, dlHi, NVT, Hi, 1012 DAG.getConstant(LVT.getSizeInBits(), TLI.getPointerTy())); 1013 return DAG.getNode(ISD::OR, dlHi, NVT, Lo, Hi); 1014 } 1015 1016 /// LibCallify - Convert the node into a libcall with the same prototype. 1017 SDValue DAGTypeLegalizer::LibCallify(RTLIB::Libcall LC, SDNode *N, 1018 bool isSigned) { 1019 unsigned NumOps = N->getNumOperands(); 1020 DebugLoc dl = N->getDebugLoc(); 1021 if (NumOps == 0) { 1022 return MakeLibCall(LC, N->getValueType(0), 0, 0, isSigned, dl); 1023 } else if (NumOps == 1) { 1024 SDValue Op = N->getOperand(0); 1025 return MakeLibCall(LC, N->getValueType(0), &Op, 1, isSigned, dl); 1026 } else if (NumOps == 2) { 1027 SDValue Ops[2] = { N->getOperand(0), N->getOperand(1) }; 1028 return MakeLibCall(LC, N->getValueType(0), Ops, 2, isSigned, dl); 1029 } 1030 SmallVector<SDValue, 8> Ops(NumOps); 1031 for (unsigned i = 0; i < NumOps; ++i) 1032 Ops[i] = N->getOperand(i); 1033 1034 return MakeLibCall(LC, N->getValueType(0), &Ops[0], NumOps, isSigned, dl); 1035 } 1036 1037 /// MakeLibCall - Generate a libcall taking the given operands as arguments and 1038 /// returning a result of type RetVT. 1039 SDValue DAGTypeLegalizer::MakeLibCall(RTLIB::Libcall LC, EVT RetVT, 1040 const SDValue *Ops, unsigned NumOps, 1041 bool isSigned, DebugLoc dl) { 1042 TargetLowering::ArgListTy Args; 1043 Args.reserve(NumOps); 1044 1045 TargetLowering::ArgListEntry Entry; 1046 for (unsigned i = 0; i != NumOps; ++i) { 1047 Entry.Node = Ops[i]; 1048 Entry.Ty = Entry.Node.getValueType().getTypeForEVT(*DAG.getContext()); 1049 Entry.isSExt = isSigned; 1050 Entry.isZExt = !isSigned; 1051 Args.push_back(Entry); 1052 } 1053 SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC), 1054 TLI.getPointerTy()); 1055 1056 Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext()); 1057 std::pair<SDValue,SDValue> CallInfo = 1058 TLI.LowerCallTo(DAG.getEntryNode(), RetTy, isSigned, !isSigned, false, 1059 false, 0, TLI.getLibcallCallingConv(LC), 1060 /*isTailCall=*/false, 1061 /*doesNotReturn=*/false, /*isReturnValueUsed=*/true, 1062 Callee, Args, DAG, dl); 1063 return CallInfo.first; 1064 } 1065 1066 // ExpandChainLibCall - Expand a node into a call to a libcall. Similar to 1067 // ExpandLibCall except that the first operand is the in-chain. 1068 std::pair<SDValue, SDValue> 1069 DAGTypeLegalizer::ExpandChainLibCall(RTLIB::Libcall LC, 1070 SDNode *Node, 1071 bool isSigned) { 1072 SDValue InChain = Node->getOperand(0); 1073 1074 TargetLowering::ArgListTy Args; 1075 TargetLowering::ArgListEntry Entry; 1076 for (unsigned i = 1, e = Node->getNumOperands(); i != e; ++i) { 1077 EVT ArgVT = Node->getOperand(i).getValueType(); 1078 Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext()); 1079 Entry.Node = Node->getOperand(i); 1080 Entry.Ty = ArgTy; 1081 Entry.isSExt = isSigned; 1082 Entry.isZExt = !isSigned; 1083 Args.push_back(Entry); 1084 } 1085 SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC), 1086 TLI.getPointerTy()); 1087 1088 Type *RetTy = Node->getValueType(0).getTypeForEVT(*DAG.getContext()); 1089 std::pair<SDValue, SDValue> CallInfo = 1090 TLI.LowerCallTo(InChain, RetTy, isSigned, !isSigned, false, false, 1091 0, TLI.getLibcallCallingConv(LC), /*isTailCall=*/false, 1092 /*doesNotReturn=*/false, /*isReturnValueUsed=*/true, 1093 Callee, Args, DAG, Node->getDebugLoc()); 1094 1095 return CallInfo; 1096 } 1097 1098 /// PromoteTargetBoolean - Promote the given target boolean to a target boolean 1099 /// of the given type. A target boolean is an integer value, not necessarily of 1100 /// type i1, the bits of which conform to getBooleanContents. 1101 SDValue DAGTypeLegalizer::PromoteTargetBoolean(SDValue Bool, EVT VT) { 1102 DebugLoc dl = Bool.getDebugLoc(); 1103 ISD::NodeType ExtendCode = 1104 TargetLowering::getExtendForContent(TLI.getBooleanContents(VT.isVector())); 1105 return DAG.getNode(ExtendCode, dl, VT, Bool); 1106 } 1107 1108 /// SplitInteger - Return the lower LoVT bits of Op in Lo and the upper HiVT 1109 /// bits in Hi. 1110 void DAGTypeLegalizer::SplitInteger(SDValue Op, 1111 EVT LoVT, EVT HiVT, 1112 SDValue &Lo, SDValue &Hi) { 1113 DebugLoc dl = Op.getDebugLoc(); 1114 assert(LoVT.getSizeInBits() + HiVT.getSizeInBits() == 1115 Op.getValueType().getSizeInBits() && "Invalid integer splitting!"); 1116 Lo = DAG.getNode(ISD::TRUNCATE, dl, LoVT, Op); 1117 Hi = DAG.getNode(ISD::SRL, dl, Op.getValueType(), Op, 1118 DAG.getConstant(LoVT.getSizeInBits(), TLI.getPointerTy())); 1119 Hi = DAG.getNode(ISD::TRUNCATE, dl, HiVT, Hi); 1120 } 1121 1122 /// SplitInteger - Return the lower and upper halves of Op's bits in a value 1123 /// type half the size of Op's. 1124 void DAGTypeLegalizer::SplitInteger(SDValue Op, 1125 SDValue &Lo, SDValue &Hi) { 1126 EVT HalfVT = EVT::getIntegerVT(*DAG.getContext(), 1127 Op.getValueType().getSizeInBits()/2); 1128 SplitInteger(Op, HalfVT, HalfVT, Lo, Hi); 1129 } 1130 1131 1132 //===----------------------------------------------------------------------===// 1133 // Entry Point 1134 //===----------------------------------------------------------------------===// 1135 1136 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that 1137 /// only uses types natively supported by the target. Returns "true" if it made 1138 /// any changes. 1139 /// 1140 /// Note that this is an involved process that may invalidate pointers into 1141 /// the graph. 1142 bool SelectionDAG::LegalizeTypes() { 1143 return DAGTypeLegalizer(*this).run(); 1144 } 1145