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/ADT/SetVector.h" 18 #include "llvm/IR/CallingConv.h" 19 #include "llvm/IR/DataLayout.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 #define DEBUG_TYPE "legalize-types" 26 27 static cl::opt<bool> 28 EnableExpensiveChecks("enable-legalize-types-checking", cl::Hidden); 29 30 /// Do extensive, expensive, sanity checking. 31 void DAGTypeLegalizer::PerformExpensiveChecks() { 32 // If a node is not processed, then none of its values should be mapped by any 33 // of PromotedIntegers, ExpandedIntegers, ..., ReplacedValues. 34 35 // If a node is processed, then each value with an illegal type must be mapped 36 // by exactly one of PromotedIntegers, ExpandedIntegers, ..., ReplacedValues. 37 // Values with a legal type may be mapped by ReplacedValues, but not by any of 38 // the other maps. 39 40 // Note that these invariants may not hold momentarily when processing a node: 41 // the node being processed may be put in a map before being marked Processed. 42 43 // Note that it is possible to have nodes marked NewNode in the DAG. This can 44 // occur in two ways. Firstly, a node may be created during legalization but 45 // never passed to the legalization core. This is usually due to the implicit 46 // folding that occurs when using the DAG.getNode operators. Secondly, a new 47 // node may be passed to the legalization core, but when analyzed may morph 48 // into a different node, leaving the original node as a NewNode in the DAG. 49 // A node may morph if one of its operands changes during analysis. Whether 50 // it actually morphs or not depends on whether, after updating its operands, 51 // it is equivalent to an existing node: if so, it morphs into that existing 52 // node (CSE). An operand can change during analysis if the operand is a new 53 // node that morphs, or it is a processed value that was mapped to some other 54 // value (as recorded in ReplacedValues) in which case the operand is turned 55 // into that other value. If a node morphs then the node it morphed into will 56 // be used instead of it for legalization, however the original node continues 57 // to live on in the DAG. 58 // The conclusion is that though there may be nodes marked NewNode in the DAG, 59 // all uses of such nodes are also marked NewNode: the result is a fungus of 60 // NewNodes growing on top of the useful nodes, and perhaps using them, but 61 // not used by them. 62 63 // If a value is mapped by ReplacedValues, then it must have no uses, except 64 // by nodes marked NewNode (see above). 65 66 // The final node obtained by mapping by ReplacedValues is not marked NewNode. 67 // Note that ReplacedValues should be applied iteratively. 68 69 // Note that the ReplacedValues map may also map deleted nodes (by iterating 70 // over the DAG we never dereference deleted nodes). This means that it may 71 // also map nodes marked NewNode if the deallocated memory was reallocated as 72 // another node, and that new node was not seen by the LegalizeTypes machinery 73 // (for example because it was created but not used). In general, we cannot 74 // distinguish between new nodes and deleted nodes. 75 SmallVector<SDNode*, 16> NewNodes; 76 for (SDNode &Node : DAG.allnodes()) { 77 // Remember nodes marked NewNode - they are subject to extra checking below. 78 if (Node.getNodeId() == NewNode) 79 NewNodes.push_back(&Node); 80 81 for (unsigned i = 0, e = Node.getNumValues(); i != e; ++i) { 82 SDValue Res(&Node, i); 83 bool Failed = false; 84 85 unsigned Mapped = 0; 86 if (ReplacedValues.find(Res) != ReplacedValues.end()) { 87 Mapped |= 1; 88 // Check that remapped values are only used by nodes marked NewNode. 89 for (SDNode::use_iterator UI = Node.use_begin(), UE = Node.use_end(); 90 UI != UE; ++UI) 91 if (UI.getUse().getResNo() == i) 92 assert(UI->getNodeId() == NewNode && 93 "Remapped value has non-trivial use!"); 94 95 // Check that the final result of applying ReplacedValues is not 96 // marked NewNode. 97 SDValue NewVal = ReplacedValues[Res]; 98 DenseMap<SDValue, SDValue>::iterator I = ReplacedValues.find(NewVal); 99 while (I != ReplacedValues.end()) { 100 NewVal = I->second; 101 I = ReplacedValues.find(NewVal); 102 } 103 assert(NewVal.getNode()->getNodeId() != NewNode && 104 "ReplacedValues maps to a new node!"); 105 } 106 if (PromotedIntegers.find(Res) != PromotedIntegers.end()) 107 Mapped |= 2; 108 if (SoftenedFloats.find(Res) != SoftenedFloats.end()) 109 Mapped |= 4; 110 if (ScalarizedVectors.find(Res) != ScalarizedVectors.end()) 111 Mapped |= 8; 112 if (ExpandedIntegers.find(Res) != ExpandedIntegers.end()) 113 Mapped |= 16; 114 if (ExpandedFloats.find(Res) != ExpandedFloats.end()) 115 Mapped |= 32; 116 if (SplitVectors.find(Res) != SplitVectors.end()) 117 Mapped |= 64; 118 if (WidenedVectors.find(Res) != WidenedVectors.end()) 119 Mapped |= 128; 120 121 if (Node.getNodeId() != Processed) { 122 // Since we allow ReplacedValues to map deleted nodes, it may map nodes 123 // marked NewNode too, since a deleted node may have been reallocated as 124 // another node that has not been seen by the LegalizeTypes machinery. 125 if ((Node.getNodeId() == NewNode && Mapped > 1) || 126 (Node.getNodeId() != NewNode && Mapped != 0)) { 127 dbgs() << "Unprocessed value in a map!"; 128 Failed = true; 129 } 130 } else if (isTypeLegal(Res.getValueType()) || IgnoreNodeResults(&Node)) { 131 if (Mapped > 1) { 132 dbgs() << "Value with legal type was transformed!"; 133 Failed = true; 134 } 135 } else { 136 if (Mapped == 0) { 137 dbgs() << "Processed value not in any map!"; 138 Failed = true; 139 } else if (Mapped & (Mapped - 1)) { 140 dbgs() << "Value in multiple maps!"; 141 Failed = true; 142 } 143 } 144 145 if (Failed) { 146 if (Mapped & 1) 147 dbgs() << " ReplacedValues"; 148 if (Mapped & 2) 149 dbgs() << " PromotedIntegers"; 150 if (Mapped & 4) 151 dbgs() << " SoftenedFloats"; 152 if (Mapped & 8) 153 dbgs() << " ScalarizedVectors"; 154 if (Mapped & 16) 155 dbgs() << " ExpandedIntegers"; 156 if (Mapped & 32) 157 dbgs() << " ExpandedFloats"; 158 if (Mapped & 64) 159 dbgs() << " SplitVectors"; 160 if (Mapped & 128) 161 dbgs() << " WidenedVectors"; 162 dbgs() << "\n"; 163 llvm_unreachable(nullptr); 164 } 165 } 166 } 167 168 // Checked that NewNodes are only used by other NewNodes. 169 for (unsigned i = 0, e = NewNodes.size(); i != e; ++i) { 170 SDNode *N = NewNodes[i]; 171 for (SDNode::use_iterator UI = N->use_begin(), UE = N->use_end(); 172 UI != UE; ++UI) 173 assert(UI->getNodeId() == NewNode && "NewNode used by non-NewNode!"); 174 } 175 } 176 177 /// This is the main entry point for the type legalizer. This does a top-down 178 /// traversal of the dag, legalizing types as it goes. Returns "true" if it made 179 /// any changes. 180 bool DAGTypeLegalizer::run() { 181 bool Changed = false; 182 183 // Create a dummy node (which is not added to allnodes), that adds a reference 184 // to the root node, preventing it from being deleted, and tracking any 185 // changes of the root. 186 HandleSDNode Dummy(DAG.getRoot()); 187 Dummy.setNodeId(Unanalyzed); 188 189 // The root of the dag may dangle to deleted nodes until the type legalizer is 190 // done. Set it to null to avoid confusion. 191 DAG.setRoot(SDValue()); 192 193 // Walk all nodes in the graph, assigning them a NodeId of 'ReadyToProcess' 194 // (and remembering them) if they are leaves and assigning 'Unanalyzed' if 195 // non-leaves. 196 for (SDNode &Node : DAG.allnodes()) { 197 if (Node.getNumOperands() == 0) { 198 Node.setNodeId(ReadyToProcess); 199 Worklist.push_back(&Node); 200 } else { 201 Node.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 EXPENSIVE_CHECKS 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 Changed = SoftenFloatResult(N, i); 242 if (Changed) 243 goto NodeDone; 244 // If not changed, the result type should be legally in register. 245 assert(isLegalInHWReg(ResultVT) && 246 "Unchanged SoftenFloatResult should be legal in register!"); 247 goto ScanOperands; 248 case TargetLowering::TypeExpandFloat: 249 ExpandFloatResult(N, i); 250 Changed = true; 251 goto NodeDone; 252 case TargetLowering::TypeScalarizeVector: 253 ScalarizeVectorResult(N, i); 254 Changed = true; 255 goto NodeDone; 256 case TargetLowering::TypeSplitVector: 257 SplitVectorResult(N, i); 258 Changed = true; 259 goto NodeDone; 260 case TargetLowering::TypeWidenVector: 261 WidenVectorResult(N, i); 262 Changed = true; 263 goto NodeDone; 264 case TargetLowering::TypePromoteFloat: 265 PromoteFloatResult(N, i); 266 Changed = true; 267 goto NodeDone; 268 } 269 } 270 271 ScanOperands: 272 // Scan the operand list for the node, handling any nodes with operands that 273 // are illegal. 274 { 275 unsigned NumOperands = N->getNumOperands(); 276 bool NeedsReanalyzing = false; 277 unsigned i; 278 for (i = 0; i != NumOperands; ++i) { 279 if (IgnoreNodeResults(N->getOperand(i).getNode())) 280 continue; 281 282 EVT OpVT = N->getOperand(i).getValueType(); 283 switch (getTypeAction(OpVT)) { 284 case TargetLowering::TypeLegal: 285 continue; 286 // The following calls must either replace all of the node's results 287 // using ReplaceValueWith, and return "false"; or update the node's 288 // operands in place, and return "true". 289 case TargetLowering::TypePromoteInteger: 290 NeedsReanalyzing = PromoteIntegerOperand(N, i); 291 Changed = true; 292 break; 293 case TargetLowering::TypeExpandInteger: 294 NeedsReanalyzing = ExpandIntegerOperand(N, i); 295 Changed = true; 296 break; 297 case TargetLowering::TypeSoftenFloat: 298 NeedsReanalyzing = SoftenFloatOperand(N, i); 299 Changed = true; 300 break; 301 case TargetLowering::TypeExpandFloat: 302 NeedsReanalyzing = ExpandFloatOperand(N, i); 303 Changed = true; 304 break; 305 case TargetLowering::TypeScalarizeVector: 306 NeedsReanalyzing = ScalarizeVectorOperand(N, i); 307 Changed = true; 308 break; 309 case TargetLowering::TypeSplitVector: 310 NeedsReanalyzing = SplitVectorOperand(N, i); 311 Changed = true; 312 break; 313 case TargetLowering::TypeWidenVector: 314 NeedsReanalyzing = WidenVectorOperand(N, i); 315 Changed = true; 316 break; 317 case TargetLowering::TypePromoteFloat: 318 NeedsReanalyzing = PromoteFloatOperand(N, i); 319 Changed = true; 320 break; 321 } 322 break; 323 } 324 325 // The sub-method updated N in place. Check to see if any operands are new, 326 // and if so, mark them. If the node needs revisiting, don't add all users 327 // to the worklist etc. 328 if (NeedsReanalyzing) { 329 assert(N->getNodeId() == ReadyToProcess && "Node ID recalculated?"); 330 N->setNodeId(NewNode); 331 // Recompute the NodeId and correct processed operands, adding the node to 332 // the worklist if ready. 333 SDNode *M = AnalyzeNewNode(N); 334 if (M == N) 335 // The node didn't morph - nothing special to do, it will be revisited. 336 continue; 337 338 // The node morphed - this is equivalent to legalizing by replacing every 339 // value of N with the corresponding value of M. So do that now. 340 assert(N->getNumValues() == M->getNumValues() && 341 "Node morphing changed the number of results!"); 342 for (unsigned i = 0, e = N->getNumValues(); i != e; ++i) 343 // Replacing the value takes care of remapping the new value. 344 ReplaceValueWith(SDValue(N, i), SDValue(M, i)); 345 assert(N->getNodeId() == NewNode && "Unexpected node state!"); 346 // The node continues to live on as part of the NewNode fungus that 347 // grows on top of the useful nodes. Nothing more needs to be done 348 // with it - move on to the next node. 349 continue; 350 } 351 352 if (i == NumOperands) { 353 DEBUG(dbgs() << "Legally typed node: "; N->dump(&DAG); dbgs() << "\n"); 354 } 355 } 356 NodeDone: 357 358 // If we reach here, the node was processed, potentially creating new nodes. 359 // Mark it as processed and add its users to the worklist as appropriate. 360 assert(N->getNodeId() == ReadyToProcess && "Node ID recalculated?"); 361 N->setNodeId(Processed); 362 363 for (SDNode::use_iterator UI = N->use_begin(), E = N->use_end(); 364 UI != E; ++UI) { 365 SDNode *User = *UI; 366 int NodeId = User->getNodeId(); 367 368 // This node has two options: it can either be a new node or its Node ID 369 // may be a count of the number of operands it has that are not ready. 370 if (NodeId > 0) { 371 User->setNodeId(NodeId-1); 372 373 // If this was the last use it was waiting on, add it to the ready list. 374 if (NodeId-1 == ReadyToProcess) 375 Worklist.push_back(User); 376 continue; 377 } 378 379 // If this is an unreachable new node, then ignore it. If it ever becomes 380 // reachable by being used by a newly created node then it will be handled 381 // by AnalyzeNewNode. 382 if (NodeId == NewNode) 383 continue; 384 385 // Otherwise, this node is new: this is the first operand of it that 386 // became ready. Its new NodeId is the number of operands it has minus 1 387 // (as this node is now processed). 388 assert(NodeId == Unanalyzed && "Unknown node ID!"); 389 User->setNodeId(User->getNumOperands() - 1); 390 391 // If the node only has a single operand, it is now ready. 392 if (User->getNumOperands() == 1) 393 Worklist.push_back(User); 394 } 395 } 396 397 #ifndef EXPENSIVE_CHECKS 398 if (EnableExpensiveChecks) 399 #endif 400 PerformExpensiveChecks(); 401 402 // If the root changed (e.g. it was a dead load) update the root. 403 DAG.setRoot(Dummy.getValue()); 404 405 // Remove dead nodes. This is important to do for cleanliness but also before 406 // the checking loop below. Implicit folding by the DAG.getNode operators and 407 // node morphing can cause unreachable nodes to be around with their flags set 408 // to new. 409 DAG.RemoveDeadNodes(); 410 411 // In a debug build, scan all the nodes to make sure we found them all. This 412 // ensures that there are no cycles and that everything got processed. 413 #ifndef NDEBUG 414 for (SDNode &Node : DAG.allnodes()) { 415 bool Failed = false; 416 417 // Check that all result types are legal. 418 // A value type is illegal if its TypeAction is not TypeLegal, 419 // and TLI.RegClassForVT does not have a register class for this type. 420 // For example, the x86_64 target has f128 that is not TypeLegal, 421 // to have softened operators, but it also has FR128 register class to 422 // pass and return f128 values. Hence a legalized node can have f128 type. 423 if (!IgnoreNodeResults(&Node)) 424 for (unsigned i = 0, NumVals = Node.getNumValues(); i < NumVals; ++i) 425 if (!isTypeLegal(Node.getValueType(i)) && 426 !TLI.isTypeLegal(Node.getValueType(i))) { 427 dbgs() << "Result type " << i << " illegal: "; 428 Node.dump(); 429 Failed = true; 430 } 431 432 // Check that all operand types are legal. 433 for (unsigned i = 0, NumOps = Node.getNumOperands(); i < NumOps; ++i) 434 if (!IgnoreNodeResults(Node.getOperand(i).getNode()) && 435 !isTypeLegal(Node.getOperand(i).getValueType()) && 436 !TLI.isTypeLegal(Node.getOperand(i).getValueType())) { 437 dbgs() << "Operand type " << i << " illegal: "; 438 Node.getOperand(i).dump(); 439 Failed = true; 440 } 441 442 if (Node.getNodeId() != Processed) { 443 if (Node.getNodeId() == NewNode) 444 dbgs() << "New node not analyzed?\n"; 445 else if (Node.getNodeId() == Unanalyzed) 446 dbgs() << "Unanalyzed node not noticed?\n"; 447 else if (Node.getNodeId() > 0) 448 dbgs() << "Operand not processed?\n"; 449 else if (Node.getNodeId() == ReadyToProcess) 450 dbgs() << "Not added to worklist?\n"; 451 Failed = true; 452 } 453 454 if (Failed) { 455 Node.dump(&DAG); dbgs() << "\n"; 456 llvm_unreachable(nullptr); 457 } 458 } 459 #endif 460 461 return Changed; 462 } 463 464 /// The specified node is the root of a subtree of potentially new nodes. 465 /// Correct any processed operands (this may change the node) and calculate the 466 /// NodeId. If the node itself changes to a processed node, it is not remapped - 467 /// the caller needs to take care of this. Returns the potentially changed node. 468 SDNode *DAGTypeLegalizer::AnalyzeNewNode(SDNode *N) { 469 // If this was an existing node that is already done, we're done. 470 if (N->getNodeId() != NewNode && N->getNodeId() != Unanalyzed) 471 return N; 472 473 // Remove any stale map entries. 474 ExpungeNode(N); 475 476 // Okay, we know that this node is new. Recursively walk all of its operands 477 // to see if they are new also. The depth of this walk is bounded by the size 478 // of the new tree that was constructed (usually 2-3 nodes), so we don't worry 479 // about revisiting of nodes. 480 // 481 // As we walk the operands, keep track of the number of nodes that are 482 // processed. If non-zero, this will become the new nodeid of this node. 483 // Operands may morph when they are analyzed. If so, the node will be 484 // updated after all operands have been analyzed. Since this is rare, 485 // the code tries to minimize overhead in the non-morphing case. 486 487 SmallVector<SDValue, 8> NewOps; 488 unsigned NumProcessed = 0; 489 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) { 490 SDValue OrigOp = N->getOperand(i); 491 SDValue Op = OrigOp; 492 493 AnalyzeNewValue(Op); // Op may morph. 494 495 if (Op.getNode()->getNodeId() == Processed) 496 ++NumProcessed; 497 498 if (!NewOps.empty()) { 499 // Some previous operand changed. Add this one to the list. 500 NewOps.push_back(Op); 501 } else if (Op != OrigOp) { 502 // This is the first operand to change - add all operands so far. 503 NewOps.append(N->op_begin(), N->op_begin() + i); 504 NewOps.push_back(Op); 505 } 506 } 507 508 // Some operands changed - update the node. 509 if (!NewOps.empty()) { 510 SDNode *M = DAG.UpdateNodeOperands(N, NewOps); 511 if (M != N) { 512 // The node morphed into a different node. Normally for this to happen 513 // the original node would have to be marked NewNode. However this can 514 // in theory momentarily not be the case while ReplaceValueWith is doing 515 // its stuff. Mark the original node NewNode to help sanity checking. 516 N->setNodeId(NewNode); 517 if (M->getNodeId() != NewNode && M->getNodeId() != Unanalyzed) 518 // It morphed into a previously analyzed node - nothing more to do. 519 return M; 520 521 // It morphed into a different new node. Do the equivalent of passing 522 // it to AnalyzeNewNode: expunge it and calculate the NodeId. No need 523 // to remap the operands, since they are the same as the operands we 524 // remapped above. 525 N = M; 526 ExpungeNode(N); 527 } 528 } 529 530 // Calculate the NodeId. 531 N->setNodeId(N->getNumOperands() - NumProcessed); 532 if (N->getNodeId() == ReadyToProcess) 533 Worklist.push_back(N); 534 535 return N; 536 } 537 538 /// Call AnalyzeNewNode, updating the node in Val if needed. 539 /// If the node changes to a processed node, then remap it. 540 void DAGTypeLegalizer::AnalyzeNewValue(SDValue &Val) { 541 Val.setNode(AnalyzeNewNode(Val.getNode())); 542 if (Val.getNode()->getNodeId() == Processed) 543 // We were passed a processed node, or it morphed into one - remap it. 544 RemapValue(Val); 545 } 546 547 /// If N has a bogus mapping in ReplacedValues, eliminate it. 548 /// This can occur when a node is deleted then reallocated as a new node - 549 /// the mapping in ReplacedValues applies to the deleted node, not the new 550 /// one. 551 /// The only map that can have a deleted node as a source is ReplacedValues. 552 /// Other maps can have deleted nodes as targets, but since their looked-up 553 /// values are always immediately remapped using RemapValue, resulting in a 554 /// not-deleted node, this is harmless as long as ReplacedValues/RemapValue 555 /// always performs correct mappings. In order to keep the mapping correct, 556 /// ExpungeNode should be called on any new nodes *before* adding them as 557 /// either source or target to ReplacedValues (which typically means calling 558 /// Expunge when a new node is first seen, since it may no longer be marked 559 /// NewNode by the time it is added to ReplacedValues). 560 void DAGTypeLegalizer::ExpungeNode(SDNode *N) { 561 if (N->getNodeId() != NewNode) 562 return; 563 564 // If N is not remapped by ReplacedValues then there is nothing to do. 565 unsigned i, e; 566 for (i = 0, e = N->getNumValues(); i != e; ++i) 567 if (ReplacedValues.find(SDValue(N, i)) != ReplacedValues.end()) 568 break; 569 570 if (i == e) 571 return; 572 573 // Remove N from all maps - this is expensive but rare. 574 575 for (DenseMap<SDValue, SDValue>::iterator I = PromotedIntegers.begin(), 576 E = PromotedIntegers.end(); I != E; ++I) { 577 assert(I->first.getNode() != N); 578 RemapValue(I->second); 579 } 580 581 for (DenseMap<SDValue, SDValue>::iterator I = SoftenedFloats.begin(), 582 E = SoftenedFloats.end(); I != E; ++I) { 583 assert(I->first.getNode() != N); 584 RemapValue(I->second); 585 } 586 587 for (DenseMap<SDValue, SDValue>::iterator I = ScalarizedVectors.begin(), 588 E = ScalarizedVectors.end(); I != E; ++I) { 589 assert(I->first.getNode() != N); 590 RemapValue(I->second); 591 } 592 593 for (DenseMap<SDValue, SDValue>::iterator I = WidenedVectors.begin(), 594 E = WidenedVectors.end(); I != E; ++I) { 595 assert(I->first.getNode() != N); 596 RemapValue(I->second); 597 } 598 599 for (DenseMap<SDValue, std::pair<SDValue, SDValue> >::iterator 600 I = ExpandedIntegers.begin(), E = ExpandedIntegers.end(); I != E; ++I){ 601 assert(I->first.getNode() != N); 602 RemapValue(I->second.first); 603 RemapValue(I->second.second); 604 } 605 606 for (DenseMap<SDValue, std::pair<SDValue, SDValue> >::iterator 607 I = ExpandedFloats.begin(), E = ExpandedFloats.end(); I != E; ++I) { 608 assert(I->first.getNode() != N); 609 RemapValue(I->second.first); 610 RemapValue(I->second.second); 611 } 612 613 for (DenseMap<SDValue, std::pair<SDValue, SDValue> >::iterator 614 I = SplitVectors.begin(), E = SplitVectors.end(); I != E; ++I) { 615 assert(I->first.getNode() != N); 616 RemapValue(I->second.first); 617 RemapValue(I->second.second); 618 } 619 620 for (DenseMap<SDValue, SDValue>::iterator I = ReplacedValues.begin(), 621 E = ReplacedValues.end(); I != E; ++I) 622 RemapValue(I->second); 623 624 for (unsigned i = 0, e = N->getNumValues(); i != e; ++i) 625 ReplacedValues.erase(SDValue(N, i)); 626 } 627 628 /// If the specified value was already legalized to another value, 629 /// replace it by that value. 630 void DAGTypeLegalizer::RemapValue(SDValue &N) { 631 DenseMap<SDValue, SDValue>::iterator I = ReplacedValues.find(N); 632 if (I != ReplacedValues.end()) { 633 // Use path compression to speed up future lookups if values get multiply 634 // replaced with other values. 635 RemapValue(I->second); 636 N = I->second; 637 638 // Note that it is possible to have N.getNode()->getNodeId() == NewNode at 639 // this point because it is possible for a node to be put in the map before 640 // being processed. 641 } 642 } 643 644 namespace { 645 /// This class is a DAGUpdateListener that listens for updates to nodes and 646 /// recomputes their ready state. 647 class NodeUpdateListener : public SelectionDAG::DAGUpdateListener { 648 DAGTypeLegalizer &DTL; 649 SmallSetVector<SDNode*, 16> &NodesToAnalyze; 650 public: 651 explicit NodeUpdateListener(DAGTypeLegalizer &dtl, 652 SmallSetVector<SDNode*, 16> &nta) 653 : SelectionDAG::DAGUpdateListener(dtl.getDAG()), 654 DTL(dtl), NodesToAnalyze(nta) {} 655 656 void NodeDeleted(SDNode *N, SDNode *E) override { 657 assert(N->getNodeId() != DAGTypeLegalizer::ReadyToProcess && 658 N->getNodeId() != DAGTypeLegalizer::Processed && 659 "Invalid node ID for RAUW deletion!"); 660 // It is possible, though rare, for the deleted node N to occur as a 661 // target in a map, so note the replacement N -> E in ReplacedValues. 662 assert(E && "Node not replaced?"); 663 DTL.NoteDeletion(N, E); 664 665 // In theory the deleted node could also have been scheduled for analysis. 666 // So remove it from the set of nodes which will be analyzed. 667 NodesToAnalyze.remove(N); 668 669 // In general nothing needs to be done for E, since it didn't change but 670 // only gained new uses. However N -> E was just added to ReplacedValues, 671 // and the result of a ReplacedValues mapping is not allowed to be marked 672 // NewNode. So if E is marked NewNode, then it needs to be analyzed. 673 if (E->getNodeId() == DAGTypeLegalizer::NewNode) 674 NodesToAnalyze.insert(E); 675 } 676 677 void NodeUpdated(SDNode *N) override { 678 // Node updates can mean pretty much anything. It is possible that an 679 // operand was set to something already processed (f.e.) in which case 680 // this node could become ready. Recompute its flags. 681 assert(N->getNodeId() != DAGTypeLegalizer::ReadyToProcess && 682 N->getNodeId() != DAGTypeLegalizer::Processed && 683 "Invalid node ID for RAUW deletion!"); 684 N->setNodeId(DAGTypeLegalizer::NewNode); 685 NodesToAnalyze.insert(N); 686 } 687 }; 688 } 689 690 691 /// The specified value was legalized to the specified other value. 692 /// Update the DAG and NodeIds replacing any uses of From to use To instead. 693 void DAGTypeLegalizer::ReplaceValueWith(SDValue From, SDValue To) { 694 assert(From.getNode() != To.getNode() && "Potential legalization loop!"); 695 696 // If expansion produced new nodes, make sure they are properly marked. 697 ExpungeNode(From.getNode()); 698 AnalyzeNewValue(To); // Expunges To. 699 700 // Anything that used the old node should now use the new one. Note that this 701 // can potentially cause recursive merging. 702 SmallSetVector<SDNode*, 16> NodesToAnalyze; 703 NodeUpdateListener NUL(*this, NodesToAnalyze); 704 do { 705 DAG.ReplaceAllUsesOfValueWith(From, To); 706 707 // The old node may still be present in a map like ExpandedIntegers or 708 // PromotedIntegers. Inform maps about the replacement. 709 ReplacedValues[From] = To; 710 711 // Process the list of nodes that need to be reanalyzed. 712 while (!NodesToAnalyze.empty()) { 713 SDNode *N = NodesToAnalyze.back(); 714 NodesToAnalyze.pop_back(); 715 if (N->getNodeId() != DAGTypeLegalizer::NewNode) 716 // The node was analyzed while reanalyzing an earlier node - it is safe 717 // to skip. Note that this is not a morphing node - otherwise it would 718 // still be marked NewNode. 719 continue; 720 721 // Analyze the node's operands and recalculate the node ID. 722 SDNode *M = AnalyzeNewNode(N); 723 if (M != N) { 724 // The node morphed into a different node. Make everyone use the new 725 // node instead. 726 assert(M->getNodeId() != NewNode && "Analysis resulted in NewNode!"); 727 assert(N->getNumValues() == M->getNumValues() && 728 "Node morphing changed the number of results!"); 729 for (unsigned i = 0, e = N->getNumValues(); i != e; ++i) { 730 SDValue OldVal(N, i); 731 SDValue NewVal(M, i); 732 if (M->getNodeId() == Processed) 733 RemapValue(NewVal); 734 DAG.ReplaceAllUsesOfValueWith(OldVal, NewVal); 735 // OldVal may be a target of the ReplacedValues map which was marked 736 // NewNode to force reanalysis because it was updated. Ensure that 737 // anything that ReplacedValues mapped to OldVal will now be mapped 738 // all the way to NewVal. 739 ReplacedValues[OldVal] = NewVal; 740 } 741 // The original node continues to exist in the DAG, marked NewNode. 742 } 743 } 744 // When recursively update nodes with new nodes, it is possible to have 745 // new uses of From due to CSE. If this happens, replace the new uses of 746 // From with To. 747 } while (!From.use_empty()); 748 } 749 750 void DAGTypeLegalizer::SetPromotedInteger(SDValue Op, SDValue Result) { 751 assert(Result.getValueType() == 752 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType()) && 753 "Invalid type for promoted integer"); 754 AnalyzeNewValue(Result); 755 756 SDValue &OpEntry = PromotedIntegers[Op]; 757 assert(!OpEntry.getNode() && "Node is already promoted!"); 758 OpEntry = Result; 759 } 760 761 void DAGTypeLegalizer::SetSoftenedFloat(SDValue Op, SDValue Result) { 762 // f128 of x86_64 could be kept in SSE registers, 763 // but sometimes softened to i128. 764 assert((Result.getValueType() == 765 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType()) || 766 Op.getValueType() == 767 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType())) && 768 "Invalid type for softened float"); 769 AnalyzeNewValue(Result); 770 771 SDValue &OpEntry = SoftenedFloats[Op]; 772 // Allow repeated calls to save f128 type nodes 773 // or any node with type that transforms to itself. 774 // Many operations on these types are not softened. 775 assert((!OpEntry.getNode()|| 776 Op.getValueType() == 777 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType())) && 778 "Node is already converted to integer!"); 779 OpEntry = Result; 780 } 781 782 void DAGTypeLegalizer::SetPromotedFloat(SDValue Op, SDValue Result) { 783 assert(Result.getValueType() == 784 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType()) && 785 "Invalid type for promoted float"); 786 AnalyzeNewValue(Result); 787 788 SDValue &OpEntry = PromotedFloats[Op]; 789 assert(!OpEntry.getNode() && "Node is already promoted!"); 790 OpEntry = Result; 791 } 792 793 void DAGTypeLegalizer::SetScalarizedVector(SDValue Op, SDValue Result) { 794 // Note that in some cases vector operation operands may be greater than 795 // the vector element type. For example BUILD_VECTOR of type <1 x i1> with 796 // a constant i8 operand. 797 assert(Result.getValueType().getSizeInBits() >= 798 Op.getValueType().getVectorElementType().getSizeInBits() && 799 "Invalid type for scalarized vector"); 800 AnalyzeNewValue(Result); 801 802 SDValue &OpEntry = ScalarizedVectors[Op]; 803 assert(!OpEntry.getNode() && "Node is already scalarized!"); 804 OpEntry = Result; 805 } 806 807 void DAGTypeLegalizer::GetExpandedInteger(SDValue Op, SDValue &Lo, 808 SDValue &Hi) { 809 std::pair<SDValue, SDValue> &Entry = ExpandedIntegers[Op]; 810 RemapValue(Entry.first); 811 RemapValue(Entry.second); 812 assert(Entry.first.getNode() && "Operand isn't expanded"); 813 Lo = Entry.first; 814 Hi = Entry.second; 815 } 816 817 void DAGTypeLegalizer::SetExpandedInteger(SDValue Op, SDValue Lo, 818 SDValue Hi) { 819 assert(Lo.getValueType() == 820 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType()) && 821 Hi.getValueType() == Lo.getValueType() && 822 "Invalid type for expanded integer"); 823 // Lo/Hi may have been newly allocated, if so, add nodeid's as relevant. 824 AnalyzeNewValue(Lo); 825 AnalyzeNewValue(Hi); 826 827 // Remember that this is the result of the node. 828 std::pair<SDValue, SDValue> &Entry = ExpandedIntegers[Op]; 829 assert(!Entry.first.getNode() && "Node already expanded"); 830 Entry.first = Lo; 831 Entry.second = Hi; 832 } 833 834 void DAGTypeLegalizer::GetExpandedFloat(SDValue Op, SDValue &Lo, 835 SDValue &Hi) { 836 std::pair<SDValue, SDValue> &Entry = ExpandedFloats[Op]; 837 RemapValue(Entry.first); 838 RemapValue(Entry.second); 839 assert(Entry.first.getNode() && "Operand isn't expanded"); 840 Lo = Entry.first; 841 Hi = Entry.second; 842 } 843 844 void DAGTypeLegalizer::SetExpandedFloat(SDValue Op, SDValue Lo, 845 SDValue Hi) { 846 assert(Lo.getValueType() == 847 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType()) && 848 Hi.getValueType() == Lo.getValueType() && 849 "Invalid type for expanded float"); 850 // Lo/Hi may have been newly allocated, if so, add nodeid's as relevant. 851 AnalyzeNewValue(Lo); 852 AnalyzeNewValue(Hi); 853 854 // Remember that this is the result of the node. 855 std::pair<SDValue, SDValue> &Entry = ExpandedFloats[Op]; 856 assert(!Entry.first.getNode() && "Node already expanded"); 857 Entry.first = Lo; 858 Entry.second = Hi; 859 } 860 861 void DAGTypeLegalizer::GetSplitVector(SDValue Op, SDValue &Lo, 862 SDValue &Hi) { 863 std::pair<SDValue, SDValue> &Entry = SplitVectors[Op]; 864 RemapValue(Entry.first); 865 RemapValue(Entry.second); 866 assert(Entry.first.getNode() && "Operand isn't split"); 867 Lo = Entry.first; 868 Hi = Entry.second; 869 } 870 871 void DAGTypeLegalizer::SetSplitVector(SDValue Op, SDValue Lo, 872 SDValue Hi) { 873 assert(Lo.getValueType().getVectorElementType() == 874 Op.getValueType().getVectorElementType() && 875 2*Lo.getValueType().getVectorNumElements() == 876 Op.getValueType().getVectorNumElements() && 877 Hi.getValueType() == Lo.getValueType() && 878 "Invalid type for split vector"); 879 // Lo/Hi may have been newly allocated, if so, add nodeid's as relevant. 880 AnalyzeNewValue(Lo); 881 AnalyzeNewValue(Hi); 882 883 // Remember that this is the result of the node. 884 std::pair<SDValue, SDValue> &Entry = SplitVectors[Op]; 885 assert(!Entry.first.getNode() && "Node already split"); 886 Entry.first = Lo; 887 Entry.second = Hi; 888 } 889 890 void DAGTypeLegalizer::SetWidenedVector(SDValue Op, SDValue Result) { 891 assert(Result.getValueType() == 892 TLI.getTypeToTransformTo(*DAG.getContext(), Op.getValueType()) && 893 "Invalid type for widened vector"); 894 AnalyzeNewValue(Result); 895 896 SDValue &OpEntry = WidenedVectors[Op]; 897 assert(!OpEntry.getNode() && "Node already widened!"); 898 OpEntry = Result; 899 } 900 901 902 //===----------------------------------------------------------------------===// 903 // Utilities. 904 //===----------------------------------------------------------------------===// 905 906 /// Convert to an integer of the same size. 907 SDValue DAGTypeLegalizer::BitConvertToInteger(SDValue Op) { 908 unsigned BitWidth = Op.getValueType().getSizeInBits(); 909 return DAG.getNode(ISD::BITCAST, SDLoc(Op), 910 EVT::getIntegerVT(*DAG.getContext(), BitWidth), Op); 911 } 912 913 /// Convert to a vector of integers of the same size. 914 SDValue DAGTypeLegalizer::BitConvertVectorToIntegerVector(SDValue Op) { 915 assert(Op.getValueType().isVector() && "Only applies to vectors!"); 916 unsigned EltWidth = Op.getValueType().getVectorElementType().getSizeInBits(); 917 EVT EltNVT = EVT::getIntegerVT(*DAG.getContext(), EltWidth); 918 unsigned NumElts = Op.getValueType().getVectorNumElements(); 919 return DAG.getNode(ISD::BITCAST, SDLoc(Op), 920 EVT::getVectorVT(*DAG.getContext(), EltNVT, NumElts), Op); 921 } 922 923 SDValue DAGTypeLegalizer::CreateStackStoreLoad(SDValue Op, 924 EVT DestVT) { 925 SDLoc dl(Op); 926 // Create the stack frame object. Make sure it is aligned for both 927 // the source and destination types. 928 SDValue StackPtr = DAG.CreateStackTemporary(Op.getValueType(), DestVT); 929 // Emit a store to the stack slot. 930 SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, Op, StackPtr, 931 MachinePointerInfo(), false, false, 0); 932 // Result is a load from the stack slot. 933 return DAG.getLoad(DestVT, dl, Store, StackPtr, MachinePointerInfo(), 934 false, false, false, 0); 935 } 936 937 /// Replace the node's results with custom code provided by the target and 938 /// return "true", or do nothing and return "false". 939 /// The last parameter is FALSE if we are dealing with a node with legal 940 /// result types and illegal operand. The second parameter denotes the type of 941 /// illegal OperandNo in that case. 942 /// The last parameter being TRUE means we are dealing with a 943 /// node with illegal result types. The second parameter denotes the type of 944 /// illegal ResNo in that case. 945 bool DAGTypeLegalizer::CustomLowerNode(SDNode *N, EVT VT, bool LegalizeResult) { 946 // See if the target wants to custom lower this node. 947 if (TLI.getOperationAction(N->getOpcode(), VT) != TargetLowering::Custom) 948 return false; 949 950 SmallVector<SDValue, 8> Results; 951 if (LegalizeResult) 952 TLI.ReplaceNodeResults(N, Results, DAG); 953 else 954 TLI.LowerOperationWrapper(N, Results, DAG); 955 956 if (Results.empty()) 957 // The target didn't want to custom lower it after all. 958 return false; 959 960 // When called from DAGTypeLegalizer::ExpandIntegerResult, we might need to 961 // provide the same kind of custom splitting behavior. 962 if (Results.size() == N->getNumValues() + 1 && LegalizeResult) { 963 // We've legalized a return type by splitting it. If there is a chain, 964 // replace that too. 965 SetExpandedInteger(SDValue(N, 0), Results[0], Results[1]); 966 if (N->getNumValues() > 1) 967 ReplaceValueWith(SDValue(N, 1), Results[2]); 968 return true; 969 } 970 971 // Make everything that once used N's values now use those in Results instead. 972 assert(Results.size() == N->getNumValues() && 973 "Custom lowering returned the wrong number of results!"); 974 for (unsigned i = 0, e = Results.size(); i != e; ++i) { 975 ReplaceValueWith(SDValue(N, i), Results[i]); 976 } 977 return true; 978 } 979 980 981 /// Widen the node's results with custom code provided by the target and return 982 /// "true", or do nothing and return "false". 983 bool DAGTypeLegalizer::CustomWidenLowerNode(SDNode *N, EVT VT) { 984 // See if the target wants to custom lower this node. 985 if (TLI.getOperationAction(N->getOpcode(), VT) != TargetLowering::Custom) 986 return false; 987 988 SmallVector<SDValue, 8> Results; 989 TLI.ReplaceNodeResults(N, Results, DAG); 990 991 if (Results.empty()) 992 // The target didn't want to custom widen lower its result after all. 993 return false; 994 995 // Update the widening map. 996 assert(Results.size() == N->getNumValues() && 997 "Custom lowering returned the wrong number of results!"); 998 for (unsigned i = 0, e = Results.size(); i != e; ++i) 999 SetWidenedVector(SDValue(N, i), Results[i]); 1000 return true; 1001 } 1002 1003 SDValue DAGTypeLegalizer::DisintegrateMERGE_VALUES(SDNode *N, unsigned ResNo) { 1004 for (unsigned i = 0, e = N->getNumValues(); i != e; ++i) 1005 if (i != ResNo) 1006 ReplaceValueWith(SDValue(N, i), SDValue(N->getOperand(i))); 1007 return SDValue(N->getOperand(ResNo)); 1008 } 1009 1010 /// Use ISD::EXTRACT_ELEMENT nodes to extract the low and high parts of the 1011 /// given value. 1012 void DAGTypeLegalizer::GetPairElements(SDValue Pair, 1013 SDValue &Lo, SDValue &Hi) { 1014 SDLoc dl(Pair); 1015 EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), Pair.getValueType()); 1016 Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, NVT, Pair, 1017 DAG.getIntPtrConstant(0, dl)); 1018 Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, NVT, Pair, 1019 DAG.getIntPtrConstant(1, dl)); 1020 } 1021 1022 SDValue DAGTypeLegalizer::GetVectorElementPointer(SDValue VecPtr, EVT EltVT, 1023 SDValue Index) { 1024 SDLoc dl(Index); 1025 // Make sure the index type is big enough to compute in. 1026 Index = DAG.getZExtOrTrunc(Index, dl, TLI.getPointerTy(DAG.getDataLayout())); 1027 1028 // Calculate the element offset and add it to the pointer. 1029 unsigned EltSize = EltVT.getSizeInBits() / 8; // FIXME: should be ABI size. 1030 assert(EltSize * 8 == EltVT.getSizeInBits() && 1031 "Converting bits to bytes lost precision"); 1032 1033 Index = DAG.getNode(ISD::MUL, dl, Index.getValueType(), Index, 1034 DAG.getConstant(EltSize, dl, Index.getValueType())); 1035 return DAG.getNode(ISD::ADD, dl, Index.getValueType(), Index, VecPtr); 1036 } 1037 1038 /// Build an integer with low bits Lo and high bits Hi. 1039 SDValue DAGTypeLegalizer::JoinIntegers(SDValue Lo, SDValue Hi) { 1040 // Arbitrarily use dlHi for result SDLoc 1041 SDLoc dlHi(Hi); 1042 SDLoc dlLo(Lo); 1043 EVT LVT = Lo.getValueType(); 1044 EVT HVT = Hi.getValueType(); 1045 EVT NVT = EVT::getIntegerVT(*DAG.getContext(), 1046 LVT.getSizeInBits() + HVT.getSizeInBits()); 1047 1048 Lo = DAG.getNode(ISD::ZERO_EXTEND, dlLo, NVT, Lo); 1049 Hi = DAG.getNode(ISD::ANY_EXTEND, dlHi, NVT, Hi); 1050 Hi = DAG.getNode(ISD::SHL, dlHi, NVT, Hi, 1051 DAG.getConstant(LVT.getSizeInBits(), dlHi, 1052 TLI.getPointerTy(DAG.getDataLayout()))); 1053 return DAG.getNode(ISD::OR, dlHi, NVT, Lo, Hi); 1054 } 1055 1056 /// Convert the node into a libcall with the same prototype. 1057 SDValue DAGTypeLegalizer::LibCallify(RTLIB::Libcall LC, SDNode *N, 1058 bool isSigned) { 1059 unsigned NumOps = N->getNumOperands(); 1060 SDLoc dl(N); 1061 if (NumOps == 0) { 1062 return TLI.makeLibCall(DAG, LC, N->getValueType(0), None, isSigned, 1063 dl).first; 1064 } else if (NumOps == 1) { 1065 SDValue Op = N->getOperand(0); 1066 return TLI.makeLibCall(DAG, LC, N->getValueType(0), Op, isSigned, 1067 dl).first; 1068 } else if (NumOps == 2) { 1069 SDValue Ops[2] = { N->getOperand(0), N->getOperand(1) }; 1070 return TLI.makeLibCall(DAG, LC, N->getValueType(0), Ops, isSigned, 1071 dl).first; 1072 } 1073 SmallVector<SDValue, 8> Ops(NumOps); 1074 for (unsigned i = 0; i < NumOps; ++i) 1075 Ops[i] = N->getOperand(i); 1076 1077 return TLI.makeLibCall(DAG, LC, N->getValueType(0), Ops, isSigned, dl).first; 1078 } 1079 1080 /// Expand a node into a call to a libcall. Similar to ExpandLibCall except that 1081 /// the first operand is the in-chain. 1082 std::pair<SDValue, SDValue> 1083 DAGTypeLegalizer::ExpandChainLibCall(RTLIB::Libcall LC, SDNode *Node, 1084 bool isSigned) { 1085 SDValue InChain = Node->getOperand(0); 1086 1087 TargetLowering::ArgListTy Args; 1088 TargetLowering::ArgListEntry Entry; 1089 for (unsigned i = 1, e = Node->getNumOperands(); i != e; ++i) { 1090 EVT ArgVT = Node->getOperand(i).getValueType(); 1091 Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext()); 1092 Entry.Node = Node->getOperand(i); 1093 Entry.Ty = ArgTy; 1094 Entry.isSExt = isSigned; 1095 Entry.isZExt = !isSigned; 1096 Args.push_back(Entry); 1097 } 1098 SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC), 1099 TLI.getPointerTy(DAG.getDataLayout())); 1100 1101 Type *RetTy = Node->getValueType(0).getTypeForEVT(*DAG.getContext()); 1102 1103 TargetLowering::CallLoweringInfo CLI(DAG); 1104 CLI.setDebugLoc(SDLoc(Node)).setChain(InChain) 1105 .setCallee(TLI.getLibcallCallingConv(LC), RetTy, Callee, std::move(Args)) 1106 .setSExtResult(isSigned).setZExtResult(!isSigned); 1107 1108 std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI); 1109 1110 return CallInfo; 1111 } 1112 1113 /// Promote the given target boolean to a target boolean of the given type. 1114 /// A target boolean is an integer value, not necessarily of type i1, the bits 1115 /// of which conform to getBooleanContents. 1116 /// 1117 /// ValVT is the type of values that produced the boolean. 1118 SDValue DAGTypeLegalizer::PromoteTargetBoolean(SDValue Bool, EVT ValVT) { 1119 SDLoc dl(Bool); 1120 EVT BoolVT = getSetCCResultType(ValVT); 1121 ISD::NodeType ExtendCode = 1122 TargetLowering::getExtendForContent(TLI.getBooleanContents(ValVT)); 1123 return DAG.getNode(ExtendCode, dl, BoolVT, Bool); 1124 } 1125 1126 /// Widen the given target boolean to a target boolean of the given type. 1127 /// The boolean vector is widened and then promoted to match the target boolean 1128 /// type of the given ValVT. 1129 SDValue DAGTypeLegalizer::WidenTargetBoolean(SDValue Bool, EVT ValVT, 1130 bool WithZeroes) { 1131 SDLoc dl(Bool); 1132 EVT BoolVT = Bool.getValueType(); 1133 1134 assert(ValVT.getVectorNumElements() > BoolVT.getVectorNumElements() && 1135 TLI.isTypeLegal(ValVT) && 1136 "Unexpected types in WidenTargetBoolean"); 1137 EVT WideVT = EVT::getVectorVT(*DAG.getContext(), BoolVT.getScalarType(), 1138 ValVT.getVectorNumElements()); 1139 Bool = ModifyToType(Bool, WideVT, WithZeroes); 1140 return PromoteTargetBoolean(Bool, ValVT); 1141 } 1142 1143 /// Return the lower LoVT bits of Op in Lo and the upper HiVT bits in Hi. 1144 void DAGTypeLegalizer::SplitInteger(SDValue Op, 1145 EVT LoVT, EVT HiVT, 1146 SDValue &Lo, SDValue &Hi) { 1147 SDLoc dl(Op); 1148 assert(LoVT.getSizeInBits() + HiVT.getSizeInBits() == 1149 Op.getValueType().getSizeInBits() && "Invalid integer splitting!"); 1150 Lo = DAG.getNode(ISD::TRUNCATE, dl, LoVT, Op); 1151 Hi = DAG.getNode(ISD::SRL, dl, Op.getValueType(), Op, 1152 DAG.getConstant(LoVT.getSizeInBits(), dl, 1153 TLI.getPointerTy(DAG.getDataLayout()))); 1154 Hi = DAG.getNode(ISD::TRUNCATE, dl, HiVT, Hi); 1155 } 1156 1157 /// Return the lower and upper halves of Op's bits in a value type half the 1158 /// size of Op's. 1159 void DAGTypeLegalizer::SplitInteger(SDValue Op, 1160 SDValue &Lo, SDValue &Hi) { 1161 EVT HalfVT = EVT::getIntegerVT(*DAG.getContext(), 1162 Op.getValueType().getSizeInBits()/2); 1163 SplitInteger(Op, HalfVT, HalfVT, Lo, Hi); 1164 } 1165 1166 1167 //===----------------------------------------------------------------------===// 1168 // Entry Point 1169 //===----------------------------------------------------------------------===// 1170 1171 /// This transforms the SelectionDAG into a SelectionDAG that only uses types 1172 /// natively supported by the target. Returns "true" if it made any changes. 1173 /// 1174 /// Note that this is an involved process that may invalidate pointers into 1175 /// the graph. 1176 bool SelectionDAG::LegalizeTypes() { 1177 return DAGTypeLegalizer(*this).run(); 1178 } 1179