1 //===-- SelectionDAGISel.cpp - Implement the SelectionDAGISel class -------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This implements the SelectionDAGISel class.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/CodeGen/SelectionDAGISel.h"
15 #include "ScheduleDAGSDNodes.h"
16 #include "SelectionDAGBuilder.h"
17 #include "llvm/ADT/PostOrderIterator.h"
18 #include "llvm/ADT/Statistic.h"
19 #include "llvm/Analysis/AliasAnalysis.h"
20 #include "llvm/Analysis/BranchProbabilityInfo.h"
21 #include "llvm/Analysis/CFG.h"
22 #include "llvm/CodeGen/FastISel.h"
23 #include "llvm/CodeGen/FunctionLoweringInfo.h"
24 #include "llvm/CodeGen/GCMetadata.h"
25 #include "llvm/CodeGen/GCStrategy.h"
26 #include "llvm/CodeGen/MachineFrameInfo.h"
27 #include "llvm/CodeGen/MachineFunction.h"
28 #include "llvm/CodeGen/MachineInstrBuilder.h"
29 #include "llvm/CodeGen/MachineModuleInfo.h"
30 #include "llvm/CodeGen/MachineRegisterInfo.h"
31 #include "llvm/CodeGen/ScheduleHazardRecognizer.h"
32 #include "llvm/CodeGen/SchedulerRegistry.h"
33 #include "llvm/CodeGen/SelectionDAG.h"
34 #include "llvm/IR/Constants.h"
35 #include "llvm/IR/DebugInfo.h"
36 #include "llvm/IR/Function.h"
37 #include "llvm/IR/InlineAsm.h"
38 #include "llvm/IR/Instructions.h"
39 #include "llvm/IR/IntrinsicInst.h"
40 #include "llvm/IR/Intrinsics.h"
41 #include "llvm/IR/LLVMContext.h"
42 #include "llvm/IR/Module.h"
43 #include "llvm/Support/Compiler.h"
44 #include "llvm/Support/Debug.h"
45 #include "llvm/Support/ErrorHandling.h"
46 #include "llvm/Support/Timer.h"
47 #include "llvm/Support/raw_ostream.h"
48 #include "llvm/Target/TargetInstrInfo.h"
49 #include "llvm/Target/TargetIntrinsicInfo.h"
50 #include "llvm/Target/TargetLibraryInfo.h"
51 #include "llvm/Target/TargetLowering.h"
52 #include "llvm/Target/TargetMachine.h"
53 #include "llvm/Target/TargetOptions.h"
54 #include "llvm/Target/TargetRegisterInfo.h"
55 #include "llvm/Target/TargetSubtargetInfo.h"
56 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
60 #define DEBUG_TYPE "isel"
62 STATISTIC(NumFastIselFailures, "Number of instructions fast isel failed on");
63 STATISTIC(NumFastIselSuccess, "Number of instructions fast isel selected");
64 STATISTIC(NumFastIselBlocks, "Number of blocks selected entirely by fast isel");
65 STATISTIC(NumDAGBlocks, "Number of blocks selected using DAG");
66 STATISTIC(NumDAGIselRetries,"Number of times dag isel has to try another path");
67 STATISTIC(NumEntryBlocks, "Number of entry blocks encountered");
68 STATISTIC(NumFastIselFailLowerArguments,
69 "Number of entry blocks where fast isel failed to lower arguments");
73 EnableFastISelVerbose2("fast-isel-verbose2", cl::Hidden,
74 cl::desc("Enable extra verbose messages in the \"fast\" "
75 "instruction selector"));
78 STATISTIC(NumFastIselFailRet,"Fast isel fails on Ret");
79 STATISTIC(NumFastIselFailBr,"Fast isel fails on Br");
80 STATISTIC(NumFastIselFailSwitch,"Fast isel fails on Switch");
81 STATISTIC(NumFastIselFailIndirectBr,"Fast isel fails on IndirectBr");
82 STATISTIC(NumFastIselFailInvoke,"Fast isel fails on Invoke");
83 STATISTIC(NumFastIselFailResume,"Fast isel fails on Resume");
84 STATISTIC(NumFastIselFailUnreachable,"Fast isel fails on Unreachable");
86 // Standard binary operators...
87 STATISTIC(NumFastIselFailAdd,"Fast isel fails on Add");
88 STATISTIC(NumFastIselFailFAdd,"Fast isel fails on FAdd");
89 STATISTIC(NumFastIselFailSub,"Fast isel fails on Sub");
90 STATISTIC(NumFastIselFailFSub,"Fast isel fails on FSub");
91 STATISTIC(NumFastIselFailMul,"Fast isel fails on Mul");
92 STATISTIC(NumFastIselFailFMul,"Fast isel fails on FMul");
93 STATISTIC(NumFastIselFailUDiv,"Fast isel fails on UDiv");
94 STATISTIC(NumFastIselFailSDiv,"Fast isel fails on SDiv");
95 STATISTIC(NumFastIselFailFDiv,"Fast isel fails on FDiv");
96 STATISTIC(NumFastIselFailURem,"Fast isel fails on URem");
97 STATISTIC(NumFastIselFailSRem,"Fast isel fails on SRem");
98 STATISTIC(NumFastIselFailFRem,"Fast isel fails on FRem");
100 // Logical operators...
101 STATISTIC(NumFastIselFailAnd,"Fast isel fails on And");
102 STATISTIC(NumFastIselFailOr,"Fast isel fails on Or");
103 STATISTIC(NumFastIselFailXor,"Fast isel fails on Xor");
105 // Memory instructions...
106 STATISTIC(NumFastIselFailAlloca,"Fast isel fails on Alloca");
107 STATISTIC(NumFastIselFailLoad,"Fast isel fails on Load");
108 STATISTIC(NumFastIselFailStore,"Fast isel fails on Store");
109 STATISTIC(NumFastIselFailAtomicCmpXchg,"Fast isel fails on AtomicCmpXchg");
110 STATISTIC(NumFastIselFailAtomicRMW,"Fast isel fails on AtomicRWM");
111 STATISTIC(NumFastIselFailFence,"Fast isel fails on Frence");
112 STATISTIC(NumFastIselFailGetElementPtr,"Fast isel fails on GetElementPtr");
114 // Convert instructions...
115 STATISTIC(NumFastIselFailTrunc,"Fast isel fails on Trunc");
116 STATISTIC(NumFastIselFailZExt,"Fast isel fails on ZExt");
117 STATISTIC(NumFastIselFailSExt,"Fast isel fails on SExt");
118 STATISTIC(NumFastIselFailFPTrunc,"Fast isel fails on FPTrunc");
119 STATISTIC(NumFastIselFailFPExt,"Fast isel fails on FPExt");
120 STATISTIC(NumFastIselFailFPToUI,"Fast isel fails on FPToUI");
121 STATISTIC(NumFastIselFailFPToSI,"Fast isel fails on FPToSI");
122 STATISTIC(NumFastIselFailUIToFP,"Fast isel fails on UIToFP");
123 STATISTIC(NumFastIselFailSIToFP,"Fast isel fails on SIToFP");
124 STATISTIC(NumFastIselFailIntToPtr,"Fast isel fails on IntToPtr");
125 STATISTIC(NumFastIselFailPtrToInt,"Fast isel fails on PtrToInt");
126 STATISTIC(NumFastIselFailBitCast,"Fast isel fails on BitCast");
128 // Other instructions...
129 STATISTIC(NumFastIselFailICmp,"Fast isel fails on ICmp");
130 STATISTIC(NumFastIselFailFCmp,"Fast isel fails on FCmp");
131 STATISTIC(NumFastIselFailPHI,"Fast isel fails on PHI");
132 STATISTIC(NumFastIselFailSelect,"Fast isel fails on Select");
133 STATISTIC(NumFastIselFailCall,"Fast isel fails on Call");
134 STATISTIC(NumFastIselFailShl,"Fast isel fails on Shl");
135 STATISTIC(NumFastIselFailLShr,"Fast isel fails on LShr");
136 STATISTIC(NumFastIselFailAShr,"Fast isel fails on AShr");
137 STATISTIC(NumFastIselFailVAArg,"Fast isel fails on VAArg");
138 STATISTIC(NumFastIselFailExtractElement,"Fast isel fails on ExtractElement");
139 STATISTIC(NumFastIselFailInsertElement,"Fast isel fails on InsertElement");
140 STATISTIC(NumFastIselFailShuffleVector,"Fast isel fails on ShuffleVector");
141 STATISTIC(NumFastIselFailExtractValue,"Fast isel fails on ExtractValue");
142 STATISTIC(NumFastIselFailInsertValue,"Fast isel fails on InsertValue");
143 STATISTIC(NumFastIselFailLandingPad,"Fast isel fails on LandingPad");
147 EnableFastISelVerbose("fast-isel-verbose", cl::Hidden,
148 cl::desc("Enable verbose messages in the \"fast\" "
149 "instruction selector"));
151 EnableFastISelAbort("fast-isel-abort", cl::Hidden,
152 cl::desc("Enable abort calls when \"fast\" instruction selection "
153 "fails to lower an instruction"));
155 EnableFastISelAbortArgs("fast-isel-abort-args", cl::Hidden,
156 cl::desc("Enable abort calls when \"fast\" instruction selection "
157 "fails to lower a formal argument"));
161 cl::desc("use Machine Branch Probability Info"),
162 cl::init(true), cl::Hidden);
166 ViewDAGCombine1("view-dag-combine1-dags", cl::Hidden,
167 cl::desc("Pop up a window to show dags before the first "
168 "dag combine pass"));
170 ViewLegalizeTypesDAGs("view-legalize-types-dags", cl::Hidden,
171 cl::desc("Pop up a window to show dags before legalize types"));
173 ViewLegalizeDAGs("view-legalize-dags", cl::Hidden,
174 cl::desc("Pop up a window to show dags before legalize"));
176 ViewDAGCombine2("view-dag-combine2-dags", cl::Hidden,
177 cl::desc("Pop up a window to show dags before the second "
178 "dag combine pass"));
180 ViewDAGCombineLT("view-dag-combine-lt-dags", cl::Hidden,
181 cl::desc("Pop up a window to show dags before the post legalize types"
182 " dag combine pass"));
184 ViewISelDAGs("view-isel-dags", cl::Hidden,
185 cl::desc("Pop up a window to show isel dags as they are selected"));
187 ViewSchedDAGs("view-sched-dags", cl::Hidden,
188 cl::desc("Pop up a window to show sched dags as they are processed"));
190 ViewSUnitDAGs("view-sunit-dags", cl::Hidden,
191 cl::desc("Pop up a window to show SUnit dags after they are processed"));
193 static const bool ViewDAGCombine1 = false,
194 ViewLegalizeTypesDAGs = false, ViewLegalizeDAGs = false,
195 ViewDAGCombine2 = false,
196 ViewDAGCombineLT = false,
197 ViewISelDAGs = false, ViewSchedDAGs = false,
198 ViewSUnitDAGs = false;
201 //===---------------------------------------------------------------------===//
203 /// RegisterScheduler class - Track the registration of instruction schedulers.
205 //===---------------------------------------------------------------------===//
206 MachinePassRegistry RegisterScheduler::Registry;
208 //===---------------------------------------------------------------------===//
210 /// ISHeuristic command line option for instruction schedulers.
212 //===---------------------------------------------------------------------===//
213 static cl::opt<RegisterScheduler::FunctionPassCtor, false,
214 RegisterPassParser<RegisterScheduler> >
215 ISHeuristic("pre-RA-sched",
216 cl::init(&createDefaultScheduler), cl::Hidden,
217 cl::desc("Instruction schedulers available (before register"
220 static RegisterScheduler
221 defaultListDAGScheduler("default", "Best scheduler for the target",
222 createDefaultScheduler);
225 //===--------------------------------------------------------------------===//
226 /// \brief This class is used by SelectionDAGISel to temporarily override
227 /// the optimization level on a per-function basis.
228 class OptLevelChanger {
229 SelectionDAGISel &IS;
230 CodeGenOpt::Level SavedOptLevel;
234 OptLevelChanger(SelectionDAGISel &ISel,
235 CodeGenOpt::Level NewOptLevel) : IS(ISel) {
236 SavedOptLevel = IS.OptLevel;
237 if (NewOptLevel == SavedOptLevel)
239 IS.OptLevel = NewOptLevel;
240 IS.TM.setOptLevel(NewOptLevel);
241 SavedFastISel = IS.TM.Options.EnableFastISel;
242 if (NewOptLevel == CodeGenOpt::None)
243 IS.TM.setFastISel(true);
244 DEBUG(dbgs() << "\nChanging optimization level for Function "
245 << IS.MF->getFunction()->getName() << "\n");
246 DEBUG(dbgs() << "\tBefore: -O" << SavedOptLevel
247 << " ; After: -O" << NewOptLevel << "\n");
251 if (IS.OptLevel == SavedOptLevel)
253 DEBUG(dbgs() << "\nRestoring optimization level for Function "
254 << IS.MF->getFunction()->getName() << "\n");
255 DEBUG(dbgs() << "\tBefore: -O" << IS.OptLevel
256 << " ; After: -O" << SavedOptLevel << "\n");
257 IS.OptLevel = SavedOptLevel;
258 IS.TM.setOptLevel(SavedOptLevel);
259 IS.TM.setFastISel(SavedFastISel);
263 //===--------------------------------------------------------------------===//
264 /// createDefaultScheduler - This creates an instruction scheduler appropriate
266 ScheduleDAGSDNodes* createDefaultScheduler(SelectionDAGISel *IS,
267 CodeGenOpt::Level OptLevel) {
268 const TargetLowering *TLI = IS->getTargetLowering();
269 const TargetSubtargetInfo &ST = IS->TM.getSubtarget<TargetSubtargetInfo>();
271 if (OptLevel == CodeGenOpt::None || ST.useMachineScheduler() ||
272 TLI->getSchedulingPreference() == Sched::Source)
273 return createSourceListDAGScheduler(IS, OptLevel);
274 if (TLI->getSchedulingPreference() == Sched::RegPressure)
275 return createBURRListDAGScheduler(IS, OptLevel);
276 if (TLI->getSchedulingPreference() == Sched::Hybrid)
277 return createHybridListDAGScheduler(IS, OptLevel);
278 if (TLI->getSchedulingPreference() == Sched::VLIW)
279 return createVLIWDAGScheduler(IS, OptLevel);
280 assert(TLI->getSchedulingPreference() == Sched::ILP &&
281 "Unknown sched type!");
282 return createILPListDAGScheduler(IS, OptLevel);
286 // EmitInstrWithCustomInserter - This method should be implemented by targets
287 // that mark instructions with the 'usesCustomInserter' flag. These
288 // instructions are special in various ways, which require special support to
289 // insert. The specified MachineInstr is created but not inserted into any
290 // basic blocks, and this method is called to expand it into a sequence of
291 // instructions, potentially also creating new basic blocks and control flow.
292 // When new basic blocks are inserted and the edges from MBB to its successors
293 // are modified, the method should insert pairs of <OldSucc, NewSucc> into the
296 TargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
297 MachineBasicBlock *MBB) const {
299 dbgs() << "If a target marks an instruction with "
300 "'usesCustomInserter', it must implement "
301 "TargetLowering::EmitInstrWithCustomInserter!";
303 llvm_unreachable(nullptr);
306 void TargetLowering::AdjustInstrPostInstrSelection(MachineInstr *MI,
307 SDNode *Node) const {
308 assert(!MI->hasPostISelHook() &&
309 "If a target marks an instruction with 'hasPostISelHook', "
310 "it must implement TargetLowering::AdjustInstrPostInstrSelection!");
313 //===----------------------------------------------------------------------===//
314 // SelectionDAGISel code
315 //===----------------------------------------------------------------------===//
317 SelectionDAGISel::SelectionDAGISel(TargetMachine &tm,
318 CodeGenOpt::Level OL) :
319 MachineFunctionPass(ID), TM(tm),
320 FuncInfo(new FunctionLoweringInfo(TM)),
321 CurDAG(new SelectionDAG(tm, OL)),
322 SDB(new SelectionDAGBuilder(*CurDAG, *FuncInfo, OL)),
326 initializeGCModuleInfoPass(*PassRegistry::getPassRegistry());
327 initializeAliasAnalysisAnalysisGroup(*PassRegistry::getPassRegistry());
328 initializeBranchProbabilityInfoPass(*PassRegistry::getPassRegistry());
329 initializeTargetLibraryInfoPass(*PassRegistry::getPassRegistry());
332 SelectionDAGISel::~SelectionDAGISel() {
338 void SelectionDAGISel::getAnalysisUsage(AnalysisUsage &AU) const {
339 AU.addRequired<AliasAnalysis>();
340 AU.addPreserved<AliasAnalysis>();
341 AU.addRequired<GCModuleInfo>();
342 AU.addPreserved<GCModuleInfo>();
343 AU.addRequired<TargetLibraryInfo>();
344 if (UseMBPI && OptLevel != CodeGenOpt::None)
345 AU.addRequired<BranchProbabilityInfo>();
346 MachineFunctionPass::getAnalysisUsage(AU);
349 /// SplitCriticalSideEffectEdges - Look for critical edges with a PHI value that
350 /// may trap on it. In this case we have to split the edge so that the path
351 /// through the predecessor block that doesn't go to the phi block doesn't
352 /// execute the possibly trapping instruction.
354 /// This is required for correctness, so it must be done at -O0.
356 static void SplitCriticalSideEffectEdges(Function &Fn, Pass *SDISel) {
357 // Loop for blocks with phi nodes.
358 for (Function::iterator BB = Fn.begin(), E = Fn.end(); BB != E; ++BB) {
359 PHINode *PN = dyn_cast<PHINode>(BB->begin());
363 // For each block with a PHI node, check to see if any of the input values
364 // are potentially trapping constant expressions. Constant expressions are
365 // the only potentially trapping value that can occur as the argument to a
367 for (BasicBlock::iterator I = BB->begin(); (PN = dyn_cast<PHINode>(I)); ++I)
368 for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
369 ConstantExpr *CE = dyn_cast<ConstantExpr>(PN->getIncomingValue(i));
370 if (!CE || !CE->canTrap()) continue;
372 // The only case we have to worry about is when the edge is critical.
373 // Since this block has a PHI Node, we assume it has multiple input
374 // edges: check to see if the pred has multiple successors.
375 BasicBlock *Pred = PN->getIncomingBlock(i);
376 if (Pred->getTerminator()->getNumSuccessors() == 1)
379 // Okay, we have to split this edge.
380 SplitCriticalEdge(Pred->getTerminator(),
381 GetSuccessorNumber(Pred, BB), SDISel, true);
387 bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
388 // Do some sanity-checking on the command-line options.
389 assert((!EnableFastISelVerbose || TM.Options.EnableFastISel) &&
390 "-fast-isel-verbose requires -fast-isel");
391 assert((!EnableFastISelAbort || TM.Options.EnableFastISel) &&
392 "-fast-isel-abort requires -fast-isel");
394 const Function &Fn = *mf.getFunction();
395 const TargetInstrInfo &TII = *TM.getInstrInfo();
396 const TargetRegisterInfo &TRI = *TM.getRegisterInfo();
397 const TargetLowering *TLI = TM.getTargetLowering();
400 RegInfo = &MF->getRegInfo();
401 AA = &getAnalysis<AliasAnalysis>();
402 LibInfo = &getAnalysis<TargetLibraryInfo>();
403 GFI = Fn.hasGC() ? &getAnalysis<GCModuleInfo>().getFunctionInfo(Fn) : nullptr;
405 TargetSubtargetInfo &ST =
406 const_cast<TargetSubtargetInfo&>(TM.getSubtarget<TargetSubtargetInfo>());
407 ST.resetSubtargetFeatures(MF);
408 TM.resetTargetOptions(MF);
410 // Reset OptLevel to None for optnone functions.
411 CodeGenOpt::Level NewOptLevel = OptLevel;
412 if (Fn.hasFnAttribute(Attribute::OptimizeNone))
413 NewOptLevel = CodeGenOpt::None;
414 OptLevelChanger OLC(*this, NewOptLevel);
416 DEBUG(dbgs() << "\n\n\n=== " << Fn.getName() << "\n");
418 SplitCriticalSideEffectEdges(const_cast<Function&>(Fn), this);
420 CurDAG->init(*MF, TLI);
421 FuncInfo->set(Fn, *MF, CurDAG);
423 if (UseMBPI && OptLevel != CodeGenOpt::None)
424 FuncInfo->BPI = &getAnalysis<BranchProbabilityInfo>();
426 FuncInfo->BPI = nullptr;
428 SDB->init(GFI, *AA, LibInfo);
430 MF->setHasInlineAsm(false);
432 SelectAllBasicBlocks(Fn);
434 // If the first basic block in the function has live ins that need to be
435 // copied into vregs, emit the copies into the top of the block before
436 // emitting the code for the block.
437 MachineBasicBlock *EntryMBB = MF->begin();
438 RegInfo->EmitLiveInCopies(EntryMBB, TRI, TII);
440 DenseMap<unsigned, unsigned> LiveInMap;
441 if (!FuncInfo->ArgDbgValues.empty())
442 for (MachineRegisterInfo::livein_iterator LI = RegInfo->livein_begin(),
443 E = RegInfo->livein_end(); LI != E; ++LI)
445 LiveInMap.insert(std::make_pair(LI->first, LI->second));
447 // Insert DBG_VALUE instructions for function arguments to the entry block.
448 for (unsigned i = 0, e = FuncInfo->ArgDbgValues.size(); i != e; ++i) {
449 MachineInstr *MI = FuncInfo->ArgDbgValues[e-i-1];
450 bool hasFI = MI->getOperand(0).isFI();
452 hasFI ? TRI.getFrameRegister(*MF) : MI->getOperand(0).getReg();
453 if (TargetRegisterInfo::isPhysicalRegister(Reg))
454 EntryMBB->insert(EntryMBB->begin(), MI);
456 MachineInstr *Def = RegInfo->getVRegDef(Reg);
458 MachineBasicBlock::iterator InsertPos = Def;
459 // FIXME: VR def may not be in entry block.
460 Def->getParent()->insert(std::next(InsertPos), MI);
462 DEBUG(dbgs() << "Dropping debug info for dead vreg"
463 << TargetRegisterInfo::virtReg2Index(Reg) << "\n");
466 // If Reg is live-in then update debug info to track its copy in a vreg.
467 DenseMap<unsigned, unsigned>::iterator LDI = LiveInMap.find(Reg);
468 if (LDI != LiveInMap.end()) {
469 assert(!hasFI && "There's no handling of frame pointer updating here yet "
471 MachineInstr *Def = RegInfo->getVRegDef(LDI->second);
472 MachineBasicBlock::iterator InsertPos = Def;
473 const MDNode *Variable =
474 MI->getOperand(MI->getNumOperands()-1).getMetadata();
475 bool IsIndirect = MI->isIndirectDebugValue();
476 unsigned Offset = IsIndirect ? MI->getOperand(1).getImm() : 0;
477 // Def is never a terminator here, so it is ok to increment InsertPos.
478 BuildMI(*EntryMBB, ++InsertPos, MI->getDebugLoc(),
479 TII.get(TargetOpcode::DBG_VALUE),
481 LDI->second, Offset, Variable);
483 // If this vreg is directly copied into an exported register then
484 // that COPY instructions also need DBG_VALUE, if it is the only
485 // user of LDI->second.
486 MachineInstr *CopyUseMI = nullptr;
487 for (MachineRegisterInfo::use_instr_iterator
488 UI = RegInfo->use_instr_begin(LDI->second),
489 E = RegInfo->use_instr_end(); UI != E; ) {
490 MachineInstr *UseMI = &*(UI++);
491 if (UseMI->isDebugValue()) continue;
492 if (UseMI->isCopy() && !CopyUseMI && UseMI->getParent() == EntryMBB) {
493 CopyUseMI = UseMI; continue;
495 // Otherwise this is another use or second copy use.
496 CopyUseMI = nullptr; break;
499 MachineInstr *NewMI =
500 BuildMI(*MF, CopyUseMI->getDebugLoc(),
501 TII.get(TargetOpcode::DBG_VALUE),
503 CopyUseMI->getOperand(0).getReg(),
505 MachineBasicBlock::iterator Pos = CopyUseMI;
506 EntryMBB->insertAfter(Pos, NewMI);
511 // Determine if there are any calls in this machine function.
512 MachineFrameInfo *MFI = MF->getFrameInfo();
513 for (const auto &MBB : *MF) {
514 if (MFI->hasCalls() && MF->hasInlineAsm())
517 for (const auto &MI : MBB) {
518 const MCInstrDesc &MCID = TM.getInstrInfo()->get(MI.getOpcode());
519 if ((MCID.isCall() && !MCID.isReturn()) ||
520 MI.isStackAligningInlineAsm()) {
521 MFI->setHasCalls(true);
523 if (MI.isInlineAsm()) {
524 MF->setHasInlineAsm(true);
529 // Determine if there is a call to setjmp in the machine function.
530 MF->setExposesReturnsTwice(Fn.callsFunctionThatReturnsTwice());
532 // Replace forward-declared registers with the registers containing
533 // the desired value.
534 MachineRegisterInfo &MRI = MF->getRegInfo();
535 for (DenseMap<unsigned, unsigned>::iterator
536 I = FuncInfo->RegFixups.begin(), E = FuncInfo->RegFixups.end();
538 unsigned From = I->first;
539 unsigned To = I->second;
540 // If To is also scheduled to be replaced, find what its ultimate
543 DenseMap<unsigned, unsigned>::iterator J = FuncInfo->RegFixups.find(To);
547 // Make sure the new register has a sufficiently constrained register class.
548 if (TargetRegisterInfo::isVirtualRegister(From) &&
549 TargetRegisterInfo::isVirtualRegister(To))
550 MRI.constrainRegClass(To, MRI.getRegClass(From));
552 MRI.replaceRegWith(From, To);
555 // Freeze the set of reserved registers now that MachineFrameInfo has been
556 // set up. All the information required by getReservedRegs() should be
558 MRI.freezeReservedRegs(*MF);
560 // Release function-specific state. SDB and CurDAG are already cleared
564 DEBUG(dbgs() << "*** MachineFunction at end of ISel ***\n");
565 DEBUG(MF->print(dbgs()));
570 void SelectionDAGISel::SelectBasicBlock(BasicBlock::const_iterator Begin,
571 BasicBlock::const_iterator End,
573 // Lower all of the non-terminator instructions. If a call is emitted
574 // as a tail call, cease emitting nodes for this block. Terminators
575 // are handled below.
576 for (BasicBlock::const_iterator I = Begin; I != End && !SDB->HasTailCall; ++I)
579 // Make sure the root of the DAG is up-to-date.
580 CurDAG->setRoot(SDB->getControlRoot());
581 HadTailCall = SDB->HasTailCall;
584 // Final step, emit the lowered DAG as machine code.
588 void SelectionDAGISel::ComputeLiveOutVRegInfo() {
589 SmallPtrSet<SDNode*, 128> VisitedNodes;
590 SmallVector<SDNode*, 128> Worklist;
592 Worklist.push_back(CurDAG->getRoot().getNode());
598 SDNode *N = Worklist.pop_back_val();
600 // If we've already seen this node, ignore it.
601 if (!VisitedNodes.insert(N))
604 // Otherwise, add all chain operands to the worklist.
605 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
606 if (N->getOperand(i).getValueType() == MVT::Other)
607 Worklist.push_back(N->getOperand(i).getNode());
609 // If this is a CopyToReg with a vreg dest, process it.
610 if (N->getOpcode() != ISD::CopyToReg)
613 unsigned DestReg = cast<RegisterSDNode>(N->getOperand(1))->getReg();
614 if (!TargetRegisterInfo::isVirtualRegister(DestReg))
617 // Ignore non-scalar or non-integer values.
618 SDValue Src = N->getOperand(2);
619 EVT SrcVT = Src.getValueType();
620 if (!SrcVT.isInteger() || SrcVT.isVector())
623 unsigned NumSignBits = CurDAG->ComputeNumSignBits(Src);
624 CurDAG->ComputeMaskedBits(Src, KnownZero, KnownOne);
625 FuncInfo->AddLiveOutRegInfo(DestReg, NumSignBits, KnownZero, KnownOne);
626 } while (!Worklist.empty());
629 void SelectionDAGISel::CodeGenAndEmitDAG() {
630 std::string GroupName;
631 if (TimePassesIsEnabled)
632 GroupName = "Instruction Selection and Scheduling";
633 std::string BlockName;
634 int BlockNumber = -1;
637 if (ViewDAGCombine1 || ViewLegalizeTypesDAGs || ViewLegalizeDAGs ||
638 ViewDAGCombine2 || ViewDAGCombineLT || ViewISelDAGs || ViewSchedDAGs ||
642 BlockNumber = FuncInfo->MBB->getNumber();
643 BlockName = MF->getName().str() + ":" +
644 FuncInfo->MBB->getBasicBlock()->getName().str();
646 DEBUG(dbgs() << "Initial selection DAG: BB#" << BlockNumber
647 << " '" << BlockName << "'\n"; CurDAG->dump());
649 if (ViewDAGCombine1) CurDAG->viewGraph("dag-combine1 input for " + BlockName);
651 // Run the DAG combiner in pre-legalize mode.
653 NamedRegionTimer T("DAG Combining 1", GroupName, TimePassesIsEnabled);
654 CurDAG->Combine(BeforeLegalizeTypes, *AA, OptLevel);
657 DEBUG(dbgs() << "Optimized lowered selection DAG: BB#" << BlockNumber
658 << " '" << BlockName << "'\n"; CurDAG->dump());
660 // Second step, hack on the DAG until it only uses operations and types that
661 // the target supports.
662 if (ViewLegalizeTypesDAGs) CurDAG->viewGraph("legalize-types input for " +
667 NamedRegionTimer T("Type Legalization", GroupName, TimePassesIsEnabled);
668 Changed = CurDAG->LegalizeTypes();
671 DEBUG(dbgs() << "Type-legalized selection DAG: BB#" << BlockNumber
672 << " '" << BlockName << "'\n"; CurDAG->dump());
674 CurDAG->NewNodesMustHaveLegalTypes = true;
677 if (ViewDAGCombineLT)
678 CurDAG->viewGraph("dag-combine-lt input for " + BlockName);
680 // Run the DAG combiner in post-type-legalize mode.
682 NamedRegionTimer T("DAG Combining after legalize types", GroupName,
683 TimePassesIsEnabled);
684 CurDAG->Combine(AfterLegalizeTypes, *AA, OptLevel);
687 DEBUG(dbgs() << "Optimized type-legalized selection DAG: BB#" << BlockNumber
688 << " '" << BlockName << "'\n"; CurDAG->dump());
693 NamedRegionTimer T("Vector Legalization", GroupName, TimePassesIsEnabled);
694 Changed = CurDAG->LegalizeVectors();
699 NamedRegionTimer T("Type Legalization 2", GroupName, TimePassesIsEnabled);
700 CurDAG->LegalizeTypes();
703 if (ViewDAGCombineLT)
704 CurDAG->viewGraph("dag-combine-lv input for " + BlockName);
706 // Run the DAG combiner in post-type-legalize mode.
708 NamedRegionTimer T("DAG Combining after legalize vectors", GroupName,
709 TimePassesIsEnabled);
710 CurDAG->Combine(AfterLegalizeVectorOps, *AA, OptLevel);
713 DEBUG(dbgs() << "Optimized vector-legalized selection DAG: BB#"
714 << BlockNumber << " '" << BlockName << "'\n"; CurDAG->dump());
717 if (ViewLegalizeDAGs) CurDAG->viewGraph("legalize input for " + BlockName);
720 NamedRegionTimer T("DAG Legalization", GroupName, TimePassesIsEnabled);
724 DEBUG(dbgs() << "Legalized selection DAG: BB#" << BlockNumber
725 << " '" << BlockName << "'\n"; CurDAG->dump());
727 if (ViewDAGCombine2) CurDAG->viewGraph("dag-combine2 input for " + BlockName);
729 // Run the DAG combiner in post-legalize mode.
731 NamedRegionTimer T("DAG Combining 2", GroupName, TimePassesIsEnabled);
732 CurDAG->Combine(AfterLegalizeDAG, *AA, OptLevel);
735 DEBUG(dbgs() << "Optimized legalized selection DAG: BB#" << BlockNumber
736 << " '" << BlockName << "'\n"; CurDAG->dump());
738 if (OptLevel != CodeGenOpt::None)
739 ComputeLiveOutVRegInfo();
741 if (ViewISelDAGs) CurDAG->viewGraph("isel input for " + BlockName);
743 // Third, instruction select all of the operations to machine code, adding the
744 // code to the MachineBasicBlock.
746 NamedRegionTimer T("Instruction Selection", GroupName, TimePassesIsEnabled);
747 DoInstructionSelection();
750 DEBUG(dbgs() << "Selected selection DAG: BB#" << BlockNumber
751 << " '" << BlockName << "'\n"; CurDAG->dump());
753 if (ViewSchedDAGs) CurDAG->viewGraph("scheduler input for " + BlockName);
755 // Schedule machine code.
756 ScheduleDAGSDNodes *Scheduler = CreateScheduler();
758 NamedRegionTimer T("Instruction Scheduling", GroupName,
759 TimePassesIsEnabled);
760 Scheduler->Run(CurDAG, FuncInfo->MBB);
763 if (ViewSUnitDAGs) Scheduler->viewGraph();
765 // Emit machine code to BB. This can change 'BB' to the last block being
767 MachineBasicBlock *FirstMBB = FuncInfo->MBB, *LastMBB;
769 NamedRegionTimer T("Instruction Creation", GroupName, TimePassesIsEnabled);
771 // FuncInfo->InsertPt is passed by reference and set to the end of the
772 // scheduled instructions.
773 LastMBB = FuncInfo->MBB = Scheduler->EmitSchedule(FuncInfo->InsertPt);
776 // If the block was split, make sure we update any references that are used to
777 // update PHI nodes later on.
778 if (FirstMBB != LastMBB)
779 SDB->UpdateSplitBlock(FirstMBB, LastMBB);
781 // Free the scheduler state.
783 NamedRegionTimer T("Instruction Scheduling Cleanup", GroupName,
784 TimePassesIsEnabled);
788 // Free the SelectionDAG state, now that we're finished with it.
793 /// ISelUpdater - helper class to handle updates of the instruction selection
795 class ISelUpdater : public SelectionDAG::DAGUpdateListener {
796 SelectionDAG::allnodes_iterator &ISelPosition;
798 ISelUpdater(SelectionDAG &DAG, SelectionDAG::allnodes_iterator &isp)
799 : SelectionDAG::DAGUpdateListener(DAG), ISelPosition(isp) {}
801 /// NodeDeleted - Handle nodes deleted from the graph. If the node being
802 /// deleted is the current ISelPosition node, update ISelPosition.
804 void NodeDeleted(SDNode *N, SDNode *E) override {
805 if (ISelPosition == SelectionDAG::allnodes_iterator(N))
809 } // end anonymous namespace
811 void SelectionDAGISel::DoInstructionSelection() {
812 DEBUG(dbgs() << "===== Instruction selection begins: BB#"
813 << FuncInfo->MBB->getNumber()
814 << " '" << FuncInfo->MBB->getName() << "'\n");
818 // Select target instructions for the DAG.
820 // Number all nodes with a topological order and set DAGSize.
821 DAGSize = CurDAG->AssignTopologicalOrder();
823 // Create a dummy node (which is not added to allnodes), that adds
824 // a reference to the root node, preventing it from being deleted,
825 // and tracking any changes of the root.
826 HandleSDNode Dummy(CurDAG->getRoot());
827 SelectionDAG::allnodes_iterator ISelPosition (CurDAG->getRoot().getNode());
830 // Make sure that ISelPosition gets properly updated when nodes are deleted
831 // in calls made from this function.
832 ISelUpdater ISU(*CurDAG, ISelPosition);
834 // The AllNodes list is now topological-sorted. Visit the
835 // nodes by starting at the end of the list (the root of the
836 // graph) and preceding back toward the beginning (the entry
838 while (ISelPosition != CurDAG->allnodes_begin()) {
839 SDNode *Node = --ISelPosition;
840 // Skip dead nodes. DAGCombiner is expected to eliminate all dead nodes,
841 // but there are currently some corner cases that it misses. Also, this
842 // makes it theoretically possible to disable the DAGCombiner.
843 if (Node->use_empty())
846 SDNode *ResNode = Select(Node);
848 // FIXME: This is pretty gross. 'Select' should be changed to not return
849 // anything at all and this code should be nuked with a tactical strike.
851 // If node should not be replaced, continue with the next one.
852 if (ResNode == Node || Node->getOpcode() == ISD::DELETED_NODE)
856 ReplaceUses(Node, ResNode);
859 // If after the replacement this node is not used any more,
860 // remove this dead node.
861 if (Node->use_empty()) // Don't delete EntryToken, etc.
862 CurDAG->RemoveDeadNode(Node);
865 CurDAG->setRoot(Dummy.getValue());
868 DEBUG(dbgs() << "===== Instruction selection ends:\n");
870 PostprocessISelDAG();
873 /// PrepareEHLandingPad - Emit an EH_LABEL, set up live-in registers, and
874 /// do other setup for EH landing-pad blocks.
875 void SelectionDAGISel::PrepareEHLandingPad() {
876 MachineBasicBlock *MBB = FuncInfo->MBB;
878 // Add a label to mark the beginning of the landing pad. Deletion of the
879 // landing pad can thus be detected via the MachineModuleInfo.
880 MCSymbol *Label = MF->getMMI().addLandingPad(MBB);
882 // Assign the call site to the landing pad's begin label.
883 MF->getMMI().setCallSiteLandingPad(Label, SDB->LPadToCallSiteMap[MBB]);
885 const MCInstrDesc &II = TM.getInstrInfo()->get(TargetOpcode::EH_LABEL);
886 BuildMI(*MBB, FuncInfo->InsertPt, SDB->getCurDebugLoc(), II)
889 // Mark exception register as live in.
890 const TargetLowering *TLI = getTargetLowering();
891 const TargetRegisterClass *PtrRC = TLI->getRegClassFor(TLI->getPointerTy());
892 if (unsigned Reg = TLI->getExceptionPointerRegister())
893 FuncInfo->ExceptionPointerVirtReg = MBB->addLiveIn(Reg, PtrRC);
895 // Mark exception selector register as live in.
896 if (unsigned Reg = TLI->getExceptionSelectorRegister())
897 FuncInfo->ExceptionSelectorVirtReg = MBB->addLiveIn(Reg, PtrRC);
900 /// isFoldedOrDeadInstruction - Return true if the specified instruction is
901 /// side-effect free and is either dead or folded into a generated instruction.
902 /// Return false if it needs to be emitted.
903 static bool isFoldedOrDeadInstruction(const Instruction *I,
904 FunctionLoweringInfo *FuncInfo) {
905 return !I->mayWriteToMemory() && // Side-effecting instructions aren't folded.
906 !isa<TerminatorInst>(I) && // Terminators aren't folded.
907 !isa<DbgInfoIntrinsic>(I) && // Debug instructions aren't folded.
908 !isa<LandingPadInst>(I) && // Landingpad instructions aren't folded.
909 !FuncInfo->isExportedInst(I); // Exported instrs must be computed.
913 // Collect per Instruction statistics for fast-isel misses. Only those
914 // instructions that cause the bail are accounted for. It does not account for
915 // instructions higher in the block. Thus, summing the per instructions stats
916 // will not add up to what is reported by NumFastIselFailures.
917 static void collectFailStats(const Instruction *I) {
918 switch (I->getOpcode()) {
919 default: assert (0 && "<Invalid operator> ");
922 case Instruction::Ret: NumFastIselFailRet++; return;
923 case Instruction::Br: NumFastIselFailBr++; return;
924 case Instruction::Switch: NumFastIselFailSwitch++; return;
925 case Instruction::IndirectBr: NumFastIselFailIndirectBr++; return;
926 case Instruction::Invoke: NumFastIselFailInvoke++; return;
927 case Instruction::Resume: NumFastIselFailResume++; return;
928 case Instruction::Unreachable: NumFastIselFailUnreachable++; return;
930 // Standard binary operators...
931 case Instruction::Add: NumFastIselFailAdd++; return;
932 case Instruction::FAdd: NumFastIselFailFAdd++; return;
933 case Instruction::Sub: NumFastIselFailSub++; return;
934 case Instruction::FSub: NumFastIselFailFSub++; return;
935 case Instruction::Mul: NumFastIselFailMul++; return;
936 case Instruction::FMul: NumFastIselFailFMul++; return;
937 case Instruction::UDiv: NumFastIselFailUDiv++; return;
938 case Instruction::SDiv: NumFastIselFailSDiv++; return;
939 case Instruction::FDiv: NumFastIselFailFDiv++; return;
940 case Instruction::URem: NumFastIselFailURem++; return;
941 case Instruction::SRem: NumFastIselFailSRem++; return;
942 case Instruction::FRem: NumFastIselFailFRem++; return;
944 // Logical operators...
945 case Instruction::And: NumFastIselFailAnd++; return;
946 case Instruction::Or: NumFastIselFailOr++; return;
947 case Instruction::Xor: NumFastIselFailXor++; return;
949 // Memory instructions...
950 case Instruction::Alloca: NumFastIselFailAlloca++; return;
951 case Instruction::Load: NumFastIselFailLoad++; return;
952 case Instruction::Store: NumFastIselFailStore++; return;
953 case Instruction::AtomicCmpXchg: NumFastIselFailAtomicCmpXchg++; return;
954 case Instruction::AtomicRMW: NumFastIselFailAtomicRMW++; return;
955 case Instruction::Fence: NumFastIselFailFence++; return;
956 case Instruction::GetElementPtr: NumFastIselFailGetElementPtr++; return;
958 // Convert instructions...
959 case Instruction::Trunc: NumFastIselFailTrunc++; return;
960 case Instruction::ZExt: NumFastIselFailZExt++; return;
961 case Instruction::SExt: NumFastIselFailSExt++; return;
962 case Instruction::FPTrunc: NumFastIselFailFPTrunc++; return;
963 case Instruction::FPExt: NumFastIselFailFPExt++; return;
964 case Instruction::FPToUI: NumFastIselFailFPToUI++; return;
965 case Instruction::FPToSI: NumFastIselFailFPToSI++; return;
966 case Instruction::UIToFP: NumFastIselFailUIToFP++; return;
967 case Instruction::SIToFP: NumFastIselFailSIToFP++; return;
968 case Instruction::IntToPtr: NumFastIselFailIntToPtr++; return;
969 case Instruction::PtrToInt: NumFastIselFailPtrToInt++; return;
970 case Instruction::BitCast: NumFastIselFailBitCast++; return;
972 // Other instructions...
973 case Instruction::ICmp: NumFastIselFailICmp++; return;
974 case Instruction::FCmp: NumFastIselFailFCmp++; return;
975 case Instruction::PHI: NumFastIselFailPHI++; return;
976 case Instruction::Select: NumFastIselFailSelect++; return;
977 case Instruction::Call: NumFastIselFailCall++; return;
978 case Instruction::Shl: NumFastIselFailShl++; return;
979 case Instruction::LShr: NumFastIselFailLShr++; return;
980 case Instruction::AShr: NumFastIselFailAShr++; return;
981 case Instruction::VAArg: NumFastIselFailVAArg++; return;
982 case Instruction::ExtractElement: NumFastIselFailExtractElement++; return;
983 case Instruction::InsertElement: NumFastIselFailInsertElement++; return;
984 case Instruction::ShuffleVector: NumFastIselFailShuffleVector++; return;
985 case Instruction::ExtractValue: NumFastIselFailExtractValue++; return;
986 case Instruction::InsertValue: NumFastIselFailInsertValue++; return;
987 case Instruction::LandingPad: NumFastIselFailLandingPad++; return;
992 void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
993 // Initialize the Fast-ISel state, if needed.
994 FastISel *FastIS = nullptr;
995 if (TM.Options.EnableFastISel)
996 FastIS = getTargetLowering()->createFastISel(*FuncInfo, LibInfo);
998 // Iterate over all basic blocks in the function.
999 ReversePostOrderTraversal<const Function*> RPOT(&Fn);
1000 for (ReversePostOrderTraversal<const Function*>::rpo_iterator
1001 I = RPOT.begin(), E = RPOT.end(); I != E; ++I) {
1002 const BasicBlock *LLVMBB = *I;
1004 if (OptLevel != CodeGenOpt::None) {
1005 bool AllPredsVisited = true;
1006 for (const_pred_iterator PI = pred_begin(LLVMBB), PE = pred_end(LLVMBB);
1008 if (!FuncInfo->VisitedBBs.count(*PI)) {
1009 AllPredsVisited = false;
1014 if (AllPredsVisited) {
1015 for (BasicBlock::const_iterator I = LLVMBB->begin();
1016 const PHINode *PN = dyn_cast<PHINode>(I); ++I)
1017 FuncInfo->ComputePHILiveOutRegInfo(PN);
1019 for (BasicBlock::const_iterator I = LLVMBB->begin();
1020 const PHINode *PN = dyn_cast<PHINode>(I); ++I)
1021 FuncInfo->InvalidatePHILiveOutRegInfo(PN);
1024 FuncInfo->VisitedBBs.insert(LLVMBB);
1027 BasicBlock::const_iterator const Begin = LLVMBB->getFirstNonPHI();
1028 BasicBlock::const_iterator const End = LLVMBB->end();
1029 BasicBlock::const_iterator BI = End;
1031 FuncInfo->MBB = FuncInfo->MBBMap[LLVMBB];
1032 FuncInfo->InsertPt = FuncInfo->MBB->getFirstNonPHI();
1034 // Setup an EH landing-pad block.
1035 FuncInfo->ExceptionPointerVirtReg = 0;
1036 FuncInfo->ExceptionSelectorVirtReg = 0;
1037 if (FuncInfo->MBB->isLandingPad())
1038 PrepareEHLandingPad();
1040 // Before doing SelectionDAG ISel, see if FastISel has been requested.
1042 FastIS->startNewBlock();
1044 // Emit code for any incoming arguments. This must happen before
1045 // beginning FastISel on the entry block.
1046 if (LLVMBB == &Fn.getEntryBlock()) {
1049 // Lower any arguments needed in this block if this is the entry block.
1050 if (!FastIS->LowerArguments()) {
1051 // Fast isel failed to lower these arguments
1052 ++NumFastIselFailLowerArguments;
1053 if (EnableFastISelAbortArgs)
1054 llvm_unreachable("FastISel didn't lower all arguments");
1056 // Use SelectionDAG argument lowering
1058 CurDAG->setRoot(SDB->getControlRoot());
1060 CodeGenAndEmitDAG();
1063 // If we inserted any instructions at the beginning, make a note of
1064 // where they are, so we can be sure to emit subsequent instructions
1066 if (FuncInfo->InsertPt != FuncInfo->MBB->begin())
1067 FastIS->setLastLocalValue(std::prev(FuncInfo->InsertPt));
1069 FastIS->setLastLocalValue(nullptr);
1072 unsigned NumFastIselRemaining = std::distance(Begin, End);
1073 // Do FastISel on as many instructions as possible.
1074 for (; BI != Begin; --BI) {
1075 const Instruction *Inst = std::prev(BI);
1077 // If we no longer require this instruction, skip it.
1078 if (isFoldedOrDeadInstruction(Inst, FuncInfo)) {
1079 --NumFastIselRemaining;
1083 // Bottom-up: reset the insert pos at the top, after any local-value
1085 FastIS->recomputeInsertPt();
1087 // Try to select the instruction with FastISel.
1088 if (FastIS->SelectInstruction(Inst)) {
1089 --NumFastIselRemaining;
1090 ++NumFastIselSuccess;
1091 // If fast isel succeeded, skip over all the folded instructions, and
1092 // then see if there is a load right before the selected instructions.
1093 // Try to fold the load if so.
1094 const Instruction *BeforeInst = Inst;
1095 while (BeforeInst != Begin) {
1096 BeforeInst = std::prev(BasicBlock::const_iterator(BeforeInst));
1097 if (!isFoldedOrDeadInstruction(BeforeInst, FuncInfo))
1100 if (BeforeInst != Inst && isa<LoadInst>(BeforeInst) &&
1101 BeforeInst->hasOneUse() &&
1102 FastIS->tryToFoldLoad(cast<LoadInst>(BeforeInst), Inst)) {
1103 // If we succeeded, don't re-select the load.
1104 BI = std::next(BasicBlock::const_iterator(BeforeInst));
1105 --NumFastIselRemaining;
1106 ++NumFastIselSuccess;
1112 if (EnableFastISelVerbose2)
1113 collectFailStats(Inst);
1116 // Then handle certain instructions as single-LLVM-Instruction blocks.
1117 if (isa<CallInst>(Inst)) {
1119 if (EnableFastISelVerbose || EnableFastISelAbort) {
1120 dbgs() << "FastISel missed call: ";
1124 if (!Inst->getType()->isVoidTy() && !Inst->use_empty()) {
1125 unsigned &R = FuncInfo->ValueMap[Inst];
1127 R = FuncInfo->CreateRegs(Inst->getType());
1130 bool HadTailCall = false;
1131 MachineBasicBlock::iterator SavedInsertPt = FuncInfo->InsertPt;
1132 SelectBasicBlock(Inst, BI, HadTailCall);
1134 // If the call was emitted as a tail call, we're done with the block.
1135 // We also need to delete any previously emitted instructions.
1137 FastIS->removeDeadCode(SavedInsertPt, FuncInfo->MBB->end());
1142 // Recompute NumFastIselRemaining as Selection DAG instruction
1143 // selection may have handled the call, input args, etc.
1144 unsigned RemainingNow = std::distance(Begin, BI);
1145 NumFastIselFailures += NumFastIselRemaining - RemainingNow;
1146 NumFastIselRemaining = RemainingNow;
1150 if (isa<TerminatorInst>(Inst) && !isa<BranchInst>(Inst)) {
1151 // Don't abort, and use a different message for terminator misses.
1152 NumFastIselFailures += NumFastIselRemaining;
1153 if (EnableFastISelVerbose || EnableFastISelAbort) {
1154 dbgs() << "FastISel missed terminator: ";
1158 NumFastIselFailures += NumFastIselRemaining;
1159 if (EnableFastISelVerbose || EnableFastISelAbort) {
1160 dbgs() << "FastISel miss: ";
1163 if (EnableFastISelAbort)
1164 // The "fast" selector couldn't handle something and bailed.
1165 // For the purpose of debugging, just abort.
1166 llvm_unreachable("FastISel didn't select the entire block");
1171 FastIS->recomputeInsertPt();
1173 // Lower any arguments needed in this block if this is the entry block.
1174 if (LLVMBB == &Fn.getEntryBlock()) {
1183 ++NumFastIselBlocks;
1186 // Run SelectionDAG instruction selection on the remainder of the block
1187 // not handled by FastISel. If FastISel is not run, this is the entire
1190 SelectBasicBlock(Begin, BI, HadTailCall);
1194 FuncInfo->PHINodesToUpdate.clear();
1198 SDB->clearDanglingDebugInfo();
1199 SDB->SPDescriptor.resetPerFunctionState();
1202 /// Given that the input MI is before a partial terminator sequence TSeq, return
1203 /// true if M + TSeq also a partial terminator sequence.
1205 /// A Terminator sequence is a sequence of MachineInstrs which at this point in
1206 /// lowering copy vregs into physical registers, which are then passed into
1207 /// terminator instructors so we can satisfy ABI constraints. A partial
1208 /// terminator sequence is an improper subset of a terminator sequence (i.e. it
1209 /// may be the whole terminator sequence).
1210 static bool MIIsInTerminatorSequence(const MachineInstr *MI) {
1211 // If we do not have a copy or an implicit def, we return true if and only if
1212 // MI is a debug value.
1213 if (!MI->isCopy() && !MI->isImplicitDef())
1214 // Sometimes DBG_VALUE MI sneak in between the copies from the vregs to the
1215 // physical registers if there is debug info associated with the terminator
1216 // of our mbb. We want to include said debug info in our terminator
1217 // sequence, so we return true in that case.
1218 return MI->isDebugValue();
1220 // We have left the terminator sequence if we are not doing one of the
1223 // 1. Copying a vreg into a physical register.
1224 // 2. Copying a vreg into a vreg.
1225 // 3. Defining a register via an implicit def.
1227 // OPI should always be a register definition...
1228 MachineInstr::const_mop_iterator OPI = MI->operands_begin();
1229 if (!OPI->isReg() || !OPI->isDef())
1232 // Defining any register via an implicit def is always ok.
1233 if (MI->isImplicitDef())
1236 // Grab the copy source...
1237 MachineInstr::const_mop_iterator OPI2 = OPI;
1239 assert(OPI2 != MI->operands_end()
1240 && "Should have a copy implying we should have 2 arguments.");
1242 // Make sure that the copy dest is not a vreg when the copy source is a
1243 // physical register.
1244 if (!OPI2->isReg() ||
1245 (!TargetRegisterInfo::isPhysicalRegister(OPI->getReg()) &&
1246 TargetRegisterInfo::isPhysicalRegister(OPI2->getReg())))
1252 /// Find the split point at which to splice the end of BB into its success stack
1253 /// protector check machine basic block.
1255 /// On many platforms, due to ABI constraints, terminators, even before register
1256 /// allocation, use physical registers. This creates an issue for us since
1257 /// physical registers at this point can not travel across basic
1258 /// blocks. Luckily, selectiondag always moves physical registers into vregs
1259 /// when they enter functions and moves them through a sequence of copies back
1260 /// into the physical registers right before the terminator creating a
1261 /// ``Terminator Sequence''. This function is searching for the beginning of the
1262 /// terminator sequence so that we can ensure that we splice off not just the
1263 /// terminator, but additionally the copies that move the vregs into the
1264 /// physical registers.
1265 static MachineBasicBlock::iterator
1266 FindSplitPointForStackProtector(MachineBasicBlock *BB, DebugLoc DL) {
1267 MachineBasicBlock::iterator SplitPoint = BB->getFirstTerminator();
1269 if (SplitPoint == BB->begin())
1272 MachineBasicBlock::iterator Start = BB->begin();
1273 MachineBasicBlock::iterator Previous = SplitPoint;
1276 while (MIIsInTerminatorSequence(Previous)) {
1277 SplitPoint = Previous;
1278 if (Previous == Start)
1287 SelectionDAGISel::FinishBasicBlock() {
1289 DEBUG(dbgs() << "Total amount of phi nodes to update: "
1290 << FuncInfo->PHINodesToUpdate.size() << "\n";
1291 for (unsigned i = 0, e = FuncInfo->PHINodesToUpdate.size(); i != e; ++i)
1292 dbgs() << "Node " << i << " : ("
1293 << FuncInfo->PHINodesToUpdate[i].first
1294 << ", " << FuncInfo->PHINodesToUpdate[i].second << ")\n");
1296 const bool MustUpdatePHINodes = SDB->SwitchCases.empty() &&
1297 SDB->JTCases.empty() &&
1298 SDB->BitTestCases.empty();
1300 // Next, now that we know what the last MBB the LLVM BB expanded is, update
1301 // PHI nodes in successors.
1302 if (MustUpdatePHINodes) {
1303 for (unsigned i = 0, e = FuncInfo->PHINodesToUpdate.size(); i != e; ++i) {
1304 MachineInstrBuilder PHI(*MF, FuncInfo->PHINodesToUpdate[i].first);
1305 assert(PHI->isPHI() &&
1306 "This is not a machine PHI node that we are updating!");
1307 if (!FuncInfo->MBB->isSuccessor(PHI->getParent()))
1309 PHI.addReg(FuncInfo->PHINodesToUpdate[i].second).addMBB(FuncInfo->MBB);
1313 // Handle stack protector.
1314 if (SDB->SPDescriptor.shouldEmitStackProtector()) {
1315 MachineBasicBlock *ParentMBB = SDB->SPDescriptor.getParentMBB();
1316 MachineBasicBlock *SuccessMBB = SDB->SPDescriptor.getSuccessMBB();
1318 // Find the split point to split the parent mbb. At the same time copy all
1319 // physical registers used in the tail of parent mbb into virtual registers
1320 // before the split point and back into physical registers after the split
1321 // point. This prevents us needing to deal with Live-ins and many other
1322 // register allocation issues caused by us splitting the parent mbb. The
1323 // register allocator will clean up said virtual copies later on.
1324 MachineBasicBlock::iterator SplitPoint =
1325 FindSplitPointForStackProtector(ParentMBB, SDB->getCurDebugLoc());
1327 // Splice the terminator of ParentMBB into SuccessMBB.
1328 SuccessMBB->splice(SuccessMBB->end(), ParentMBB,
1332 // Add compare/jump on neq/jump to the parent BB.
1333 FuncInfo->MBB = ParentMBB;
1334 FuncInfo->InsertPt = ParentMBB->end();
1335 SDB->visitSPDescriptorParent(SDB->SPDescriptor, ParentMBB);
1336 CurDAG->setRoot(SDB->getRoot());
1338 CodeGenAndEmitDAG();
1340 // CodeGen Failure MBB if we have not codegened it yet.
1341 MachineBasicBlock *FailureMBB = SDB->SPDescriptor.getFailureMBB();
1342 if (!FailureMBB->size()) {
1343 FuncInfo->MBB = FailureMBB;
1344 FuncInfo->InsertPt = FailureMBB->end();
1345 SDB->visitSPDescriptorFailure(SDB->SPDescriptor);
1346 CurDAG->setRoot(SDB->getRoot());
1348 CodeGenAndEmitDAG();
1351 // Clear the Per-BB State.
1352 SDB->SPDescriptor.resetPerBBState();
1355 // If we updated PHI Nodes, return early.
1356 if (MustUpdatePHINodes)
1359 for (unsigned i = 0, e = SDB->BitTestCases.size(); i != e; ++i) {
1360 // Lower header first, if it wasn't already lowered
1361 if (!SDB->BitTestCases[i].Emitted) {
1362 // Set the current basic block to the mbb we wish to insert the code into
1363 FuncInfo->MBB = SDB->BitTestCases[i].Parent;
1364 FuncInfo->InsertPt = FuncInfo->MBB->end();
1366 SDB->visitBitTestHeader(SDB->BitTestCases[i], FuncInfo->MBB);
1367 CurDAG->setRoot(SDB->getRoot());
1369 CodeGenAndEmitDAG();
1372 uint32_t UnhandledWeight = 0;
1373 for (unsigned j = 0, ej = SDB->BitTestCases[i].Cases.size(); j != ej; ++j)
1374 UnhandledWeight += SDB->BitTestCases[i].Cases[j].ExtraWeight;
1376 for (unsigned j = 0, ej = SDB->BitTestCases[i].Cases.size(); j != ej; ++j) {
1377 UnhandledWeight -= SDB->BitTestCases[i].Cases[j].ExtraWeight;
1378 // Set the current basic block to the mbb we wish to insert the code into
1379 FuncInfo->MBB = SDB->BitTestCases[i].Cases[j].ThisBB;
1380 FuncInfo->InsertPt = FuncInfo->MBB->end();
1383 SDB->visitBitTestCase(SDB->BitTestCases[i],
1384 SDB->BitTestCases[i].Cases[j+1].ThisBB,
1386 SDB->BitTestCases[i].Reg,
1387 SDB->BitTestCases[i].Cases[j],
1390 SDB->visitBitTestCase(SDB->BitTestCases[i],
1391 SDB->BitTestCases[i].Default,
1393 SDB->BitTestCases[i].Reg,
1394 SDB->BitTestCases[i].Cases[j],
1398 CurDAG->setRoot(SDB->getRoot());
1400 CodeGenAndEmitDAG();
1404 for (unsigned pi = 0, pe = FuncInfo->PHINodesToUpdate.size();
1406 MachineInstrBuilder PHI(*MF, FuncInfo->PHINodesToUpdate[pi].first);
1407 MachineBasicBlock *PHIBB = PHI->getParent();
1408 assert(PHI->isPHI() &&
1409 "This is not a machine PHI node that we are updating!");
1410 // This is "default" BB. We have two jumps to it. From "header" BB and
1411 // from last "case" BB.
1412 if (PHIBB == SDB->BitTestCases[i].Default)
1413 PHI.addReg(FuncInfo->PHINodesToUpdate[pi].second)
1414 .addMBB(SDB->BitTestCases[i].Parent)
1415 .addReg(FuncInfo->PHINodesToUpdate[pi].second)
1416 .addMBB(SDB->BitTestCases[i].Cases.back().ThisBB);
1417 // One of "cases" BB.
1418 for (unsigned j = 0, ej = SDB->BitTestCases[i].Cases.size();
1420 MachineBasicBlock* cBB = SDB->BitTestCases[i].Cases[j].ThisBB;
1421 if (cBB->isSuccessor(PHIBB))
1422 PHI.addReg(FuncInfo->PHINodesToUpdate[pi].second).addMBB(cBB);
1426 SDB->BitTestCases.clear();
1428 // If the JumpTable record is filled in, then we need to emit a jump table.
1429 // Updating the PHI nodes is tricky in this case, since we need to determine
1430 // whether the PHI is a successor of the range check MBB or the jump table MBB
1431 for (unsigned i = 0, e = SDB->JTCases.size(); i != e; ++i) {
1432 // Lower header first, if it wasn't already lowered
1433 if (!SDB->JTCases[i].first.Emitted) {
1434 // Set the current basic block to the mbb we wish to insert the code into
1435 FuncInfo->MBB = SDB->JTCases[i].first.HeaderBB;
1436 FuncInfo->InsertPt = FuncInfo->MBB->end();
1438 SDB->visitJumpTableHeader(SDB->JTCases[i].second, SDB->JTCases[i].first,
1440 CurDAG->setRoot(SDB->getRoot());
1442 CodeGenAndEmitDAG();
1445 // Set the current basic block to the mbb we wish to insert the code into
1446 FuncInfo->MBB = SDB->JTCases[i].second.MBB;
1447 FuncInfo->InsertPt = FuncInfo->MBB->end();
1449 SDB->visitJumpTable(SDB->JTCases[i].second);
1450 CurDAG->setRoot(SDB->getRoot());
1452 CodeGenAndEmitDAG();
1455 for (unsigned pi = 0, pe = FuncInfo->PHINodesToUpdate.size();
1457 MachineInstrBuilder PHI(*MF, FuncInfo->PHINodesToUpdate[pi].first);
1458 MachineBasicBlock *PHIBB = PHI->getParent();
1459 assert(PHI->isPHI() &&
1460 "This is not a machine PHI node that we are updating!");
1461 // "default" BB. We can go there only from header BB.
1462 if (PHIBB == SDB->JTCases[i].second.Default)
1463 PHI.addReg(FuncInfo->PHINodesToUpdate[pi].second)
1464 .addMBB(SDB->JTCases[i].first.HeaderBB);
1465 // JT BB. Just iterate over successors here
1466 if (FuncInfo->MBB->isSuccessor(PHIBB))
1467 PHI.addReg(FuncInfo->PHINodesToUpdate[pi].second).addMBB(FuncInfo->MBB);
1470 SDB->JTCases.clear();
1472 // If the switch block involved a branch to one of the actual successors, we
1473 // need to update PHI nodes in that block.
1474 for (unsigned i = 0, e = FuncInfo->PHINodesToUpdate.size(); i != e; ++i) {
1475 MachineInstrBuilder PHI(*MF, FuncInfo->PHINodesToUpdate[i].first);
1476 assert(PHI->isPHI() &&
1477 "This is not a machine PHI node that we are updating!");
1478 if (FuncInfo->MBB->isSuccessor(PHI->getParent()))
1479 PHI.addReg(FuncInfo->PHINodesToUpdate[i].second).addMBB(FuncInfo->MBB);
1482 // If we generated any switch lowering information, build and codegen any
1483 // additional DAGs necessary.
1484 for (unsigned i = 0, e = SDB->SwitchCases.size(); i != e; ++i) {
1485 // Set the current basic block to the mbb we wish to insert the code into
1486 FuncInfo->MBB = SDB->SwitchCases[i].ThisBB;
1487 FuncInfo->InsertPt = FuncInfo->MBB->end();
1489 // Determine the unique successors.
1490 SmallVector<MachineBasicBlock *, 2> Succs;
1491 Succs.push_back(SDB->SwitchCases[i].TrueBB);
1492 if (SDB->SwitchCases[i].TrueBB != SDB->SwitchCases[i].FalseBB)
1493 Succs.push_back(SDB->SwitchCases[i].FalseBB);
1495 // Emit the code. Note that this could result in FuncInfo->MBB being split.
1496 SDB->visitSwitchCase(SDB->SwitchCases[i], FuncInfo->MBB);
1497 CurDAG->setRoot(SDB->getRoot());
1499 CodeGenAndEmitDAG();
1501 // Remember the last block, now that any splitting is done, for use in
1502 // populating PHI nodes in successors.
1503 MachineBasicBlock *ThisBB = FuncInfo->MBB;
1505 // Handle any PHI nodes in successors of this chunk, as if we were coming
1506 // from the original BB before switch expansion. Note that PHI nodes can
1507 // occur multiple times in PHINodesToUpdate. We have to be very careful to
1508 // handle them the right number of times.
1509 for (unsigned i = 0, e = Succs.size(); i != e; ++i) {
1510 FuncInfo->MBB = Succs[i];
1511 FuncInfo->InsertPt = FuncInfo->MBB->end();
1512 // FuncInfo->MBB may have been removed from the CFG if a branch was
1514 if (ThisBB->isSuccessor(FuncInfo->MBB)) {
1515 for (MachineBasicBlock::iterator
1516 MBBI = FuncInfo->MBB->begin(), MBBE = FuncInfo->MBB->end();
1517 MBBI != MBBE && MBBI->isPHI(); ++MBBI) {
1518 MachineInstrBuilder PHI(*MF, MBBI);
1519 // This value for this PHI node is recorded in PHINodesToUpdate.
1520 for (unsigned pn = 0; ; ++pn) {
1521 assert(pn != FuncInfo->PHINodesToUpdate.size() &&
1522 "Didn't find PHI entry!");
1523 if (FuncInfo->PHINodesToUpdate[pn].first == PHI) {
1524 PHI.addReg(FuncInfo->PHINodesToUpdate[pn].second).addMBB(ThisBB);
1532 SDB->SwitchCases.clear();
1536 /// Create the scheduler. If a specific scheduler was specified
1537 /// via the SchedulerRegistry, use it, otherwise select the
1538 /// one preferred by the target.
1540 ScheduleDAGSDNodes *SelectionDAGISel::CreateScheduler() {
1541 RegisterScheduler::FunctionPassCtor Ctor = RegisterScheduler::getDefault();
1545 RegisterScheduler::setDefault(Ctor);
1548 return Ctor(this, OptLevel);
1551 //===----------------------------------------------------------------------===//
1552 // Helper functions used by the generated instruction selector.
1553 //===----------------------------------------------------------------------===//
1554 // Calls to these methods are generated by tblgen.
1556 /// CheckAndMask - The isel is trying to match something like (and X, 255). If
1557 /// the dag combiner simplified the 255, we still want to match. RHS is the
1558 /// actual value in the DAG on the RHS of an AND, and DesiredMaskS is the value
1559 /// specified in the .td file (e.g. 255).
1560 bool SelectionDAGISel::CheckAndMask(SDValue LHS, ConstantSDNode *RHS,
1561 int64_t DesiredMaskS) const {
1562 const APInt &ActualMask = RHS->getAPIntValue();
1563 const APInt &DesiredMask = APInt(LHS.getValueSizeInBits(), DesiredMaskS);
1565 // If the actual mask exactly matches, success!
1566 if (ActualMask == DesiredMask)
1569 // If the actual AND mask is allowing unallowed bits, this doesn't match.
1570 if (ActualMask.intersects(~DesiredMask))
1573 // Otherwise, the DAG Combiner may have proven that the value coming in is
1574 // either already zero or is not demanded. Check for known zero input bits.
1575 APInt NeededMask = DesiredMask & ~ActualMask;
1576 if (CurDAG->MaskedValueIsZero(LHS, NeededMask))
1579 // TODO: check to see if missing bits are just not demanded.
1581 // Otherwise, this pattern doesn't match.
1585 /// CheckOrMask - The isel is trying to match something like (or X, 255). If
1586 /// the dag combiner simplified the 255, we still want to match. RHS is the
1587 /// actual value in the DAG on the RHS of an OR, and DesiredMaskS is the value
1588 /// specified in the .td file (e.g. 255).
1589 bool SelectionDAGISel::CheckOrMask(SDValue LHS, ConstantSDNode *RHS,
1590 int64_t DesiredMaskS) const {
1591 const APInt &ActualMask = RHS->getAPIntValue();
1592 const APInt &DesiredMask = APInt(LHS.getValueSizeInBits(), DesiredMaskS);
1594 // If the actual mask exactly matches, success!
1595 if (ActualMask == DesiredMask)
1598 // If the actual AND mask is allowing unallowed bits, this doesn't match.
1599 if (ActualMask.intersects(~DesiredMask))
1602 // Otherwise, the DAG Combiner may have proven that the value coming in is
1603 // either already zero or is not demanded. Check for known zero input bits.
1604 APInt NeededMask = DesiredMask & ~ActualMask;
1606 APInt KnownZero, KnownOne;
1607 CurDAG->ComputeMaskedBits(LHS, KnownZero, KnownOne);
1609 // If all the missing bits in the or are already known to be set, match!
1610 if ((NeededMask & KnownOne) == NeededMask)
1613 // TODO: check to see if missing bits are just not demanded.
1615 // Otherwise, this pattern doesn't match.
1620 /// SelectInlineAsmMemoryOperands - Calls to this are automatically generated
1621 /// by tblgen. Others should not call it.
1622 void SelectionDAGISel::
1623 SelectInlineAsmMemoryOperands(std::vector<SDValue> &Ops) {
1624 std::vector<SDValue> InOps;
1625 std::swap(InOps, Ops);
1627 Ops.push_back(InOps[InlineAsm::Op_InputChain]); // 0
1628 Ops.push_back(InOps[InlineAsm::Op_AsmString]); // 1
1629 Ops.push_back(InOps[InlineAsm::Op_MDNode]); // 2, !srcloc
1630 Ops.push_back(InOps[InlineAsm::Op_ExtraInfo]); // 3 (SideEffect, AlignStack)
1632 unsigned i = InlineAsm::Op_FirstOperand, e = InOps.size();
1633 if (InOps[e-1].getValueType() == MVT::Glue)
1634 --e; // Don't process a glue operand if it is here.
1637 unsigned Flags = cast<ConstantSDNode>(InOps[i])->getZExtValue();
1638 if (!InlineAsm::isMemKind(Flags)) {
1639 // Just skip over this operand, copying the operands verbatim.
1640 Ops.insert(Ops.end(), InOps.begin()+i,
1641 InOps.begin()+i+InlineAsm::getNumOperandRegisters(Flags) + 1);
1642 i += InlineAsm::getNumOperandRegisters(Flags) + 1;
1644 assert(InlineAsm::getNumOperandRegisters(Flags) == 1 &&
1645 "Memory operand with multiple values?");
1646 // Otherwise, this is a memory operand. Ask the target to select it.
1647 std::vector<SDValue> SelOps;
1648 if (SelectInlineAsmMemoryOperand(InOps[i+1], 'm', SelOps))
1649 report_fatal_error("Could not match memory address. Inline asm"
1652 // Add this to the output node.
1654 InlineAsm::getFlagWord(InlineAsm::Kind_Mem, SelOps.size());
1655 Ops.push_back(CurDAG->getTargetConstant(NewFlags, MVT::i32));
1656 Ops.insert(Ops.end(), SelOps.begin(), SelOps.end());
1661 // Add the glue input back if present.
1662 if (e != InOps.size())
1663 Ops.push_back(InOps.back());
1666 /// findGlueUse - Return use of MVT::Glue value produced by the specified
1669 static SDNode *findGlueUse(SDNode *N) {
1670 unsigned FlagResNo = N->getNumValues()-1;
1671 for (SDNode::use_iterator I = N->use_begin(), E = N->use_end(); I != E; ++I) {
1672 SDUse &Use = I.getUse();
1673 if (Use.getResNo() == FlagResNo)
1674 return Use.getUser();
1679 /// findNonImmUse - Return true if "Use" is a non-immediate use of "Def".
1680 /// This function recursively traverses up the operand chain, ignoring
1682 static bool findNonImmUse(SDNode *Use, SDNode* Def, SDNode *ImmedUse,
1683 SDNode *Root, SmallPtrSet<SDNode*, 16> &Visited,
1684 bool IgnoreChains) {
1685 // The NodeID's are given uniques ID's where a node ID is guaranteed to be
1686 // greater than all of its (recursive) operands. If we scan to a point where
1687 // 'use' is smaller than the node we're scanning for, then we know we will
1690 // The Use may be -1 (unassigned) if it is a newly allocated node. This can
1691 // happen because we scan down to newly selected nodes in the case of glue
1693 if ((Use->getNodeId() < Def->getNodeId() && Use->getNodeId() != -1))
1696 // Don't revisit nodes if we already scanned it and didn't fail, we know we
1697 // won't fail if we scan it again.
1698 if (!Visited.insert(Use))
1701 for (unsigned i = 0, e = Use->getNumOperands(); i != e; ++i) {
1702 // Ignore chain uses, they are validated by HandleMergeInputChains.
1703 if (Use->getOperand(i).getValueType() == MVT::Other && IgnoreChains)
1706 SDNode *N = Use->getOperand(i).getNode();
1708 if (Use == ImmedUse || Use == Root)
1709 continue; // We are not looking for immediate use.
1714 // Traverse up the operand chain.
1715 if (findNonImmUse(N, Def, ImmedUse, Root, Visited, IgnoreChains))
1721 /// IsProfitableToFold - Returns true if it's profitable to fold the specific
1722 /// operand node N of U during instruction selection that starts at Root.
1723 bool SelectionDAGISel::IsProfitableToFold(SDValue N, SDNode *U,
1724 SDNode *Root) const {
1725 if (OptLevel == CodeGenOpt::None) return false;
1726 return N.hasOneUse();
1729 /// IsLegalToFold - Returns true if the specific operand node N of
1730 /// U can be folded during instruction selection that starts at Root.
1731 bool SelectionDAGISel::IsLegalToFold(SDValue N, SDNode *U, SDNode *Root,
1732 CodeGenOpt::Level OptLevel,
1733 bool IgnoreChains) {
1734 if (OptLevel == CodeGenOpt::None) return false;
1736 // If Root use can somehow reach N through a path that that doesn't contain
1737 // U then folding N would create a cycle. e.g. In the following
1738 // diagram, Root can reach N through X. If N is folded into into Root, then
1739 // X is both a predecessor and a successor of U.
1750 // * indicates nodes to be folded together.
1752 // If Root produces glue, then it gets (even more) interesting. Since it
1753 // will be "glued" together with its glue use in the scheduler, we need to
1754 // check if it might reach N.
1773 // If GU (glue use) indirectly reaches N (the load), and Root folds N
1774 // (call it Fold), then X is a predecessor of GU and a successor of
1775 // Fold. But since Fold and GU are glued together, this will create
1776 // a cycle in the scheduling graph.
1778 // If the node has glue, walk down the graph to the "lowest" node in the
1780 EVT VT = Root->getValueType(Root->getNumValues()-1);
1781 while (VT == MVT::Glue) {
1782 SDNode *GU = findGlueUse(Root);
1786 VT = Root->getValueType(Root->getNumValues()-1);
1788 // If our query node has a glue result with a use, we've walked up it. If
1789 // the user (which has already been selected) has a chain or indirectly uses
1790 // the chain, our WalkChainUsers predicate will not consider it. Because of
1791 // this, we cannot ignore chains in this predicate.
1792 IgnoreChains = false;
1796 SmallPtrSet<SDNode*, 16> Visited;
1797 return !findNonImmUse(Root, N.getNode(), U, Root, Visited, IgnoreChains);
1800 SDNode *SelectionDAGISel::Select_INLINEASM(SDNode *N) {
1801 std::vector<SDValue> Ops(N->op_begin(), N->op_end());
1802 SelectInlineAsmMemoryOperands(Ops);
1804 EVT VTs[] = { MVT::Other, MVT::Glue };
1805 SDValue New = CurDAG->getNode(ISD::INLINEASM, SDLoc(N), VTs, Ops);
1807 return New.getNode();
1810 SDNode *SelectionDAGISel::Select_UNDEF(SDNode *N) {
1811 return CurDAG->SelectNodeTo(N, TargetOpcode::IMPLICIT_DEF,N->getValueType(0));
1814 /// GetVBR - decode a vbr encoding whose top bit is set.
1815 LLVM_ATTRIBUTE_ALWAYS_INLINE static uint64_t
1816 GetVBR(uint64_t Val, const unsigned char *MatcherTable, unsigned &Idx) {
1817 assert(Val >= 128 && "Not a VBR");
1818 Val &= 127; // Remove first vbr bit.
1823 NextBits = MatcherTable[Idx++];
1824 Val |= (NextBits&127) << Shift;
1826 } while (NextBits & 128);
1832 /// UpdateChainsAndGlue - When a match is complete, this method updates uses of
1833 /// interior glue and chain results to use the new glue and chain results.
1834 void SelectionDAGISel::
1835 UpdateChainsAndGlue(SDNode *NodeToMatch, SDValue InputChain,
1836 const SmallVectorImpl<SDNode*> &ChainNodesMatched,
1838 const SmallVectorImpl<SDNode*> &GlueResultNodesMatched,
1839 bool isMorphNodeTo) {
1840 SmallVector<SDNode*, 4> NowDeadNodes;
1842 // Now that all the normal results are replaced, we replace the chain and
1843 // glue results if present.
1844 if (!ChainNodesMatched.empty()) {
1845 assert(InputChain.getNode() &&
1846 "Matched input chains but didn't produce a chain");
1847 // Loop over all of the nodes we matched that produced a chain result.
1848 // Replace all the chain results with the final chain we ended up with.
1849 for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) {
1850 SDNode *ChainNode = ChainNodesMatched[i];
1852 // If this node was already deleted, don't look at it.
1853 if (ChainNode->getOpcode() == ISD::DELETED_NODE)
1856 // Don't replace the results of the root node if we're doing a
1858 if (ChainNode == NodeToMatch && isMorphNodeTo)
1861 SDValue ChainVal = SDValue(ChainNode, ChainNode->getNumValues()-1);
1862 if (ChainVal.getValueType() == MVT::Glue)
1863 ChainVal = ChainVal.getValue(ChainVal->getNumValues()-2);
1864 assert(ChainVal.getValueType() == MVT::Other && "Not a chain?");
1865 CurDAG->ReplaceAllUsesOfValueWith(ChainVal, InputChain);
1867 // If the node became dead and we haven't already seen it, delete it.
1868 if (ChainNode->use_empty() &&
1869 !std::count(NowDeadNodes.begin(), NowDeadNodes.end(), ChainNode))
1870 NowDeadNodes.push_back(ChainNode);
1874 // If the result produces glue, update any glue results in the matched
1875 // pattern with the glue result.
1876 if (InputGlue.getNode()) {
1877 // Handle any interior nodes explicitly marked.
1878 for (unsigned i = 0, e = GlueResultNodesMatched.size(); i != e; ++i) {
1879 SDNode *FRN = GlueResultNodesMatched[i];
1881 // If this node was already deleted, don't look at it.
1882 if (FRN->getOpcode() == ISD::DELETED_NODE)
1885 assert(FRN->getValueType(FRN->getNumValues()-1) == MVT::Glue &&
1886 "Doesn't have a glue result");
1887 CurDAG->ReplaceAllUsesOfValueWith(SDValue(FRN, FRN->getNumValues()-1),
1890 // If the node became dead and we haven't already seen it, delete it.
1891 if (FRN->use_empty() &&
1892 !std::count(NowDeadNodes.begin(), NowDeadNodes.end(), FRN))
1893 NowDeadNodes.push_back(FRN);
1897 if (!NowDeadNodes.empty())
1898 CurDAG->RemoveDeadNodes(NowDeadNodes);
1900 DEBUG(dbgs() << "ISEL: Match complete!\n");
1906 CR_LeadsToInteriorNode
1909 /// WalkChainUsers - Walk down the users of the specified chained node that is
1910 /// part of the pattern we're matching, looking at all of the users we find.
1911 /// This determines whether something is an interior node, whether we have a
1912 /// non-pattern node in between two pattern nodes (which prevent folding because
1913 /// it would induce a cycle) and whether we have a TokenFactor node sandwiched
1914 /// between pattern nodes (in which case the TF becomes part of the pattern).
1916 /// The walk we do here is guaranteed to be small because we quickly get down to
1917 /// already selected nodes "below" us.
1919 WalkChainUsers(const SDNode *ChainedNode,
1920 SmallVectorImpl<SDNode*> &ChainedNodesInPattern,
1921 SmallVectorImpl<SDNode*> &InteriorChainedNodes) {
1922 ChainResult Result = CR_Simple;
1924 for (SDNode::use_iterator UI = ChainedNode->use_begin(),
1925 E = ChainedNode->use_end(); UI != E; ++UI) {
1926 // Make sure the use is of the chain, not some other value we produce.
1927 if (UI.getUse().getValueType() != MVT::Other) continue;
1931 if (User->getOpcode() == ISD::HANDLENODE) // Root of the graph.
1934 // If we see an already-selected machine node, then we've gone beyond the
1935 // pattern that we're selecting down into the already selected chunk of the
1937 unsigned UserOpcode = User->getOpcode();
1938 if (User->isMachineOpcode() ||
1939 UserOpcode == ISD::CopyToReg ||
1940 UserOpcode == ISD::CopyFromReg ||
1941 UserOpcode == ISD::INLINEASM ||
1942 UserOpcode == ISD::EH_LABEL ||
1943 UserOpcode == ISD::LIFETIME_START ||
1944 UserOpcode == ISD::LIFETIME_END) {
1945 // If their node ID got reset to -1 then they've already been selected.
1946 // Treat them like a MachineOpcode.
1947 if (User->getNodeId() == -1)
1951 // If we have a TokenFactor, we handle it specially.
1952 if (User->getOpcode() != ISD::TokenFactor) {
1953 // If the node isn't a token factor and isn't part of our pattern, then it
1954 // must be a random chained node in between two nodes we're selecting.
1955 // This happens when we have something like:
1960 // Because we structurally match the load/store as a read/modify/write,
1961 // but the call is chained between them. We cannot fold in this case
1962 // because it would induce a cycle in the graph.
1963 if (!std::count(ChainedNodesInPattern.begin(),
1964 ChainedNodesInPattern.end(), User))
1965 return CR_InducesCycle;
1967 // Otherwise we found a node that is part of our pattern. For example in:
1971 // This would happen when we're scanning down from the load and see the
1972 // store as a user. Record that there is a use of ChainedNode that is
1973 // part of the pattern and keep scanning uses.
1974 Result = CR_LeadsToInteriorNode;
1975 InteriorChainedNodes.push_back(User);
1979 // If we found a TokenFactor, there are two cases to consider: first if the
1980 // TokenFactor is just hanging "below" the pattern we're matching (i.e. no
1981 // uses of the TF are in our pattern) we just want to ignore it. Second,
1982 // the TokenFactor can be sandwiched in between two chained nodes, like so:
1988 // | \ DAG's like cheese
1991 // [TokenFactor] [Op]
1998 // In this case, the TokenFactor becomes part of our match and we rewrite it
1999 // as a new TokenFactor.
2001 // To distinguish these two cases, do a recursive walk down the uses.
2002 switch (WalkChainUsers(User, ChainedNodesInPattern, InteriorChainedNodes)) {
2004 // If the uses of the TokenFactor are just already-selected nodes, ignore
2005 // it, it is "below" our pattern.
2007 case CR_InducesCycle:
2008 // If the uses of the TokenFactor lead to nodes that are not part of our
2009 // pattern that are not selected, folding would turn this into a cycle,
2011 return CR_InducesCycle;
2012 case CR_LeadsToInteriorNode:
2013 break; // Otherwise, keep processing.
2016 // Okay, we know we're in the interesting interior case. The TokenFactor
2017 // is now going to be considered part of the pattern so that we rewrite its
2018 // uses (it may have uses that are not part of the pattern) with the
2019 // ultimate chain result of the generated code. We will also add its chain
2020 // inputs as inputs to the ultimate TokenFactor we create.
2021 Result = CR_LeadsToInteriorNode;
2022 ChainedNodesInPattern.push_back(User);
2023 InteriorChainedNodes.push_back(User);
2030 /// HandleMergeInputChains - This implements the OPC_EmitMergeInputChains
2031 /// operation for when the pattern matched at least one node with a chains. The
2032 /// input vector contains a list of all of the chained nodes that we match. We
2033 /// must determine if this is a valid thing to cover (i.e. matching it won't
2034 /// induce cycles in the DAG) and if so, creating a TokenFactor node. that will
2035 /// be used as the input node chain for the generated nodes.
2037 HandleMergeInputChains(SmallVectorImpl<SDNode*> &ChainNodesMatched,
2038 SelectionDAG *CurDAG) {
2039 // Walk all of the chained nodes we've matched, recursively scanning down the
2040 // users of the chain result. This adds any TokenFactor nodes that are caught
2041 // in between chained nodes to the chained and interior nodes list.
2042 SmallVector<SDNode*, 3> InteriorChainedNodes;
2043 for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) {
2044 if (WalkChainUsers(ChainNodesMatched[i], ChainNodesMatched,
2045 InteriorChainedNodes) == CR_InducesCycle)
2046 return SDValue(); // Would induce a cycle.
2049 // Okay, we have walked all the matched nodes and collected TokenFactor nodes
2050 // that we are interested in. Form our input TokenFactor node.
2051 SmallVector<SDValue, 3> InputChains;
2052 for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) {
2053 // Add the input chain of this node to the InputChains list (which will be
2054 // the operands of the generated TokenFactor) if it's not an interior node.
2055 SDNode *N = ChainNodesMatched[i];
2056 if (N->getOpcode() != ISD::TokenFactor) {
2057 if (std::count(InteriorChainedNodes.begin(),InteriorChainedNodes.end(),N))
2060 // Otherwise, add the input chain.
2061 SDValue InChain = ChainNodesMatched[i]->getOperand(0);
2062 assert(InChain.getValueType() == MVT::Other && "Not a chain");
2063 InputChains.push_back(InChain);
2067 // If we have a token factor, we want to add all inputs of the token factor
2068 // that are not part of the pattern we're matching.
2069 for (unsigned op = 0, e = N->getNumOperands(); op != e; ++op) {
2070 if (!std::count(ChainNodesMatched.begin(), ChainNodesMatched.end(),
2071 N->getOperand(op).getNode()))
2072 InputChains.push_back(N->getOperand(op));
2076 if (InputChains.size() == 1)
2077 return InputChains[0];
2078 return CurDAG->getNode(ISD::TokenFactor, SDLoc(ChainNodesMatched[0]),
2079 MVT::Other, InputChains);
2082 /// MorphNode - Handle morphing a node in place for the selector.
2083 SDNode *SelectionDAGISel::
2084 MorphNode(SDNode *Node, unsigned TargetOpc, SDVTList VTList,
2085 ArrayRef<SDValue> Ops, unsigned EmitNodeInfo) {
2086 // It is possible we're using MorphNodeTo to replace a node with no
2087 // normal results with one that has a normal result (or we could be
2088 // adding a chain) and the input could have glue and chains as well.
2089 // In this case we need to shift the operands down.
2090 // FIXME: This is a horrible hack and broken in obscure cases, no worse
2091 // than the old isel though.
2092 int OldGlueResultNo = -1, OldChainResultNo = -1;
2094 unsigned NTMNumResults = Node->getNumValues();
2095 if (Node->getValueType(NTMNumResults-1) == MVT::Glue) {
2096 OldGlueResultNo = NTMNumResults-1;
2097 if (NTMNumResults != 1 &&
2098 Node->getValueType(NTMNumResults-2) == MVT::Other)
2099 OldChainResultNo = NTMNumResults-2;
2100 } else if (Node->getValueType(NTMNumResults-1) == MVT::Other)
2101 OldChainResultNo = NTMNumResults-1;
2103 // Call the underlying SelectionDAG routine to do the transmogrification. Note
2104 // that this deletes operands of the old node that become dead.
2105 SDNode *Res = CurDAG->MorphNodeTo(Node, ~TargetOpc, VTList, Ops);
2107 // MorphNodeTo can operate in two ways: if an existing node with the
2108 // specified operands exists, it can just return it. Otherwise, it
2109 // updates the node in place to have the requested operands.
2111 // If we updated the node in place, reset the node ID. To the isel,
2112 // this should be just like a newly allocated machine node.
2116 unsigned ResNumResults = Res->getNumValues();
2117 // Move the glue if needed.
2118 if ((EmitNodeInfo & OPFL_GlueOutput) && OldGlueResultNo != -1 &&
2119 (unsigned)OldGlueResultNo != ResNumResults-1)
2120 CurDAG->ReplaceAllUsesOfValueWith(SDValue(Node, OldGlueResultNo),
2121 SDValue(Res, ResNumResults-1));
2123 if ((EmitNodeInfo & OPFL_GlueOutput) != 0)
2126 // Move the chain reference if needed.
2127 if ((EmitNodeInfo & OPFL_Chain) && OldChainResultNo != -1 &&
2128 (unsigned)OldChainResultNo != ResNumResults-1)
2129 CurDAG->ReplaceAllUsesOfValueWith(SDValue(Node, OldChainResultNo),
2130 SDValue(Res, ResNumResults-1));
2132 // Otherwise, no replacement happened because the node already exists. Replace
2133 // Uses of the old node with the new one.
2135 CurDAG->ReplaceAllUsesWith(Node, Res);
2140 /// CheckSame - Implements OP_CheckSame.
2141 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2142 CheckSame(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2144 const SmallVectorImpl<std::pair<SDValue, SDNode*> > &RecordedNodes) {
2145 // Accept if it is exactly the same as a previously recorded node.
2146 unsigned RecNo = MatcherTable[MatcherIndex++];
2147 assert(RecNo < RecordedNodes.size() && "Invalid CheckSame");
2148 return N == RecordedNodes[RecNo].first;
2151 /// CheckChildSame - Implements OP_CheckChildXSame.
2152 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2153 CheckChildSame(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2155 const SmallVectorImpl<std::pair<SDValue, SDNode*> > &RecordedNodes,
2157 if (ChildNo >= N.getNumOperands())
2158 return false; // Match fails if out of range child #.
2159 return ::CheckSame(MatcherTable, MatcherIndex, N.getOperand(ChildNo),
2163 /// CheckPatternPredicate - Implements OP_CheckPatternPredicate.
2164 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2165 CheckPatternPredicate(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2166 const SelectionDAGISel &SDISel) {
2167 return SDISel.CheckPatternPredicate(MatcherTable[MatcherIndex++]);
2170 /// CheckNodePredicate - Implements OP_CheckNodePredicate.
2171 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2172 CheckNodePredicate(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2173 const SelectionDAGISel &SDISel, SDNode *N) {
2174 return SDISel.CheckNodePredicate(N, MatcherTable[MatcherIndex++]);
2177 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2178 CheckOpcode(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2180 uint16_t Opc = MatcherTable[MatcherIndex++];
2181 Opc |= (unsigned short)MatcherTable[MatcherIndex++] << 8;
2182 return N->getOpcode() == Opc;
2185 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2186 CheckType(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2187 SDValue N, const TargetLowering *TLI) {
2188 MVT::SimpleValueType VT = (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2189 if (N.getValueType() == VT) return true;
2191 // Handle the case when VT is iPTR.
2192 return VT == MVT::iPTR && N.getValueType() == TLI->getPointerTy();
2195 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2196 CheckChildType(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2197 SDValue N, const TargetLowering *TLI, unsigned ChildNo) {
2198 if (ChildNo >= N.getNumOperands())
2199 return false; // Match fails if out of range child #.
2200 return ::CheckType(MatcherTable, MatcherIndex, N.getOperand(ChildNo), TLI);
2203 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2204 CheckCondCode(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2206 return cast<CondCodeSDNode>(N)->get() ==
2207 (ISD::CondCode)MatcherTable[MatcherIndex++];
2210 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2211 CheckValueType(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2212 SDValue N, const TargetLowering *TLI) {
2213 MVT::SimpleValueType VT = (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2214 if (cast<VTSDNode>(N)->getVT() == VT)
2217 // Handle the case when VT is iPTR.
2218 return VT == MVT::iPTR && cast<VTSDNode>(N)->getVT() == TLI->getPointerTy();
2221 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2222 CheckInteger(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2224 int64_t Val = MatcherTable[MatcherIndex++];
2226 Val = GetVBR(Val, MatcherTable, MatcherIndex);
2228 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N);
2229 return C && C->getSExtValue() == Val;
2232 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2233 CheckChildInteger(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2234 SDValue N, unsigned ChildNo) {
2235 if (ChildNo >= N.getNumOperands())
2236 return false; // Match fails if out of range child #.
2237 return ::CheckInteger(MatcherTable, MatcherIndex, N.getOperand(ChildNo));
2240 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2241 CheckAndImm(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2242 SDValue N, const SelectionDAGISel &SDISel) {
2243 int64_t Val = MatcherTable[MatcherIndex++];
2245 Val = GetVBR(Val, MatcherTable, MatcherIndex);
2247 if (N->getOpcode() != ISD::AND) return false;
2249 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N->getOperand(1));
2250 return C && SDISel.CheckAndMask(N.getOperand(0), C, Val);
2253 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2254 CheckOrImm(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2255 SDValue N, const SelectionDAGISel &SDISel) {
2256 int64_t Val = MatcherTable[MatcherIndex++];
2258 Val = GetVBR(Val, MatcherTable, MatcherIndex);
2260 if (N->getOpcode() != ISD::OR) return false;
2262 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N->getOperand(1));
2263 return C && SDISel.CheckOrMask(N.getOperand(0), C, Val);
2266 /// IsPredicateKnownToFail - If we know how and can do so without pushing a
2267 /// scope, evaluate the current node. If the current predicate is known to
2268 /// fail, set Result=true and return anything. If the current predicate is
2269 /// known to pass, set Result=false and return the MatcherIndex to continue
2270 /// with. If the current predicate is unknown, set Result=false and return the
2271 /// MatcherIndex to continue with.
2272 static unsigned IsPredicateKnownToFail(const unsigned char *Table,
2273 unsigned Index, SDValue N,
2275 const SelectionDAGISel &SDISel,
2276 SmallVectorImpl<std::pair<SDValue, SDNode*> > &RecordedNodes) {
2277 switch (Table[Index++]) {
2280 return Index-1; // Could not evaluate this predicate.
2281 case SelectionDAGISel::OPC_CheckSame:
2282 Result = !::CheckSame(Table, Index, N, RecordedNodes);
2284 case SelectionDAGISel::OPC_CheckChild0Same:
2285 case SelectionDAGISel::OPC_CheckChild1Same:
2286 case SelectionDAGISel::OPC_CheckChild2Same:
2287 case SelectionDAGISel::OPC_CheckChild3Same:
2288 Result = !::CheckChildSame(Table, Index, N, RecordedNodes,
2289 Table[Index-1] - SelectionDAGISel::OPC_CheckChild0Same);
2291 case SelectionDAGISel::OPC_CheckPatternPredicate:
2292 Result = !::CheckPatternPredicate(Table, Index, SDISel);
2294 case SelectionDAGISel::OPC_CheckPredicate:
2295 Result = !::CheckNodePredicate(Table, Index, SDISel, N.getNode());
2297 case SelectionDAGISel::OPC_CheckOpcode:
2298 Result = !::CheckOpcode(Table, Index, N.getNode());
2300 case SelectionDAGISel::OPC_CheckType:
2301 Result = !::CheckType(Table, Index, N, SDISel.getTargetLowering());
2303 case SelectionDAGISel::OPC_CheckChild0Type:
2304 case SelectionDAGISel::OPC_CheckChild1Type:
2305 case SelectionDAGISel::OPC_CheckChild2Type:
2306 case SelectionDAGISel::OPC_CheckChild3Type:
2307 case SelectionDAGISel::OPC_CheckChild4Type:
2308 case SelectionDAGISel::OPC_CheckChild5Type:
2309 case SelectionDAGISel::OPC_CheckChild6Type:
2310 case SelectionDAGISel::OPC_CheckChild7Type:
2311 Result = !::CheckChildType(Table, Index, N, SDISel.getTargetLowering(),
2312 Table[Index-1] - SelectionDAGISel::OPC_CheckChild0Type);
2314 case SelectionDAGISel::OPC_CheckCondCode:
2315 Result = !::CheckCondCode(Table, Index, N);
2317 case SelectionDAGISel::OPC_CheckValueType:
2318 Result = !::CheckValueType(Table, Index, N, SDISel.getTargetLowering());
2320 case SelectionDAGISel::OPC_CheckInteger:
2321 Result = !::CheckInteger(Table, Index, N);
2323 case SelectionDAGISel::OPC_CheckChild0Integer:
2324 case SelectionDAGISel::OPC_CheckChild1Integer:
2325 case SelectionDAGISel::OPC_CheckChild2Integer:
2326 case SelectionDAGISel::OPC_CheckChild3Integer:
2327 case SelectionDAGISel::OPC_CheckChild4Integer:
2328 Result = !::CheckChildInteger(Table, Index, N,
2329 Table[Index-1] - SelectionDAGISel::OPC_CheckChild0Integer);
2331 case SelectionDAGISel::OPC_CheckAndImm:
2332 Result = !::CheckAndImm(Table, Index, N, SDISel);
2334 case SelectionDAGISel::OPC_CheckOrImm:
2335 Result = !::CheckOrImm(Table, Index, N, SDISel);
2343 /// FailIndex - If this match fails, this is the index to continue with.
2346 /// NodeStack - The node stack when the scope was formed.
2347 SmallVector<SDValue, 4> NodeStack;
2349 /// NumRecordedNodes - The number of recorded nodes when the scope was formed.
2350 unsigned NumRecordedNodes;
2352 /// NumMatchedMemRefs - The number of matched memref entries.
2353 unsigned NumMatchedMemRefs;
2355 /// InputChain/InputGlue - The current chain/glue
2356 SDValue InputChain, InputGlue;
2358 /// HasChainNodesMatched - True if the ChainNodesMatched list is non-empty.
2359 bool HasChainNodesMatched, HasGlueResultNodesMatched;
2364 SDNode *SelectionDAGISel::
2365 SelectCodeCommon(SDNode *NodeToMatch, const unsigned char *MatcherTable,
2366 unsigned TableSize) {
2367 // FIXME: Should these even be selected? Handle these cases in the caller?
2368 switch (NodeToMatch->getOpcode()) {
2371 case ISD::EntryToken: // These nodes remain the same.
2372 case ISD::BasicBlock:
2374 case ISD::RegisterMask:
2375 //case ISD::VALUETYPE:
2376 //case ISD::CONDCODE:
2377 case ISD::HANDLENODE:
2378 case ISD::MDNODE_SDNODE:
2379 case ISD::TargetConstant:
2380 case ISD::TargetConstantFP:
2381 case ISD::TargetConstantPool:
2382 case ISD::TargetFrameIndex:
2383 case ISD::TargetExternalSymbol:
2384 case ISD::TargetBlockAddress:
2385 case ISD::TargetJumpTable:
2386 case ISD::TargetGlobalTLSAddress:
2387 case ISD::TargetGlobalAddress:
2388 case ISD::TokenFactor:
2389 case ISD::CopyFromReg:
2390 case ISD::CopyToReg:
2392 case ISD::LIFETIME_START:
2393 case ISD::LIFETIME_END:
2394 NodeToMatch->setNodeId(-1); // Mark selected.
2396 case ISD::AssertSext:
2397 case ISD::AssertZext:
2398 CurDAG->ReplaceAllUsesOfValueWith(SDValue(NodeToMatch, 0),
2399 NodeToMatch->getOperand(0));
2401 case ISD::INLINEASM: return Select_INLINEASM(NodeToMatch);
2402 case ISD::UNDEF: return Select_UNDEF(NodeToMatch);
2405 assert(!NodeToMatch->isMachineOpcode() && "Node already selected!");
2407 // Set up the node stack with NodeToMatch as the only node on the stack.
2408 SmallVector<SDValue, 8> NodeStack;
2409 SDValue N = SDValue(NodeToMatch, 0);
2410 NodeStack.push_back(N);
2412 // MatchScopes - Scopes used when matching, if a match failure happens, this
2413 // indicates where to continue checking.
2414 SmallVector<MatchScope, 8> MatchScopes;
2416 // RecordedNodes - This is the set of nodes that have been recorded by the
2417 // state machine. The second value is the parent of the node, or null if the
2418 // root is recorded.
2419 SmallVector<std::pair<SDValue, SDNode*>, 8> RecordedNodes;
2421 // MatchedMemRefs - This is the set of MemRef's we've seen in the input
2423 SmallVector<MachineMemOperand*, 2> MatchedMemRefs;
2425 // These are the current input chain and glue for use when generating nodes.
2426 // Various Emit operations change these. For example, emitting a copytoreg
2427 // uses and updates these.
2428 SDValue InputChain, InputGlue;
2430 // ChainNodesMatched - If a pattern matches nodes that have input/output
2431 // chains, the OPC_EmitMergeInputChains operation is emitted which indicates
2432 // which ones they are. The result is captured into this list so that we can
2433 // update the chain results when the pattern is complete.
2434 SmallVector<SDNode*, 3> ChainNodesMatched;
2435 SmallVector<SDNode*, 3> GlueResultNodesMatched;
2437 DEBUG(dbgs() << "ISEL: Starting pattern match on root node: ";
2438 NodeToMatch->dump(CurDAG);
2441 // Determine where to start the interpreter. Normally we start at opcode #0,
2442 // but if the state machine starts with an OPC_SwitchOpcode, then we
2443 // accelerate the first lookup (which is guaranteed to be hot) with the
2444 // OpcodeOffset table.
2445 unsigned MatcherIndex = 0;
2447 if (!OpcodeOffset.empty()) {
2448 // Already computed the OpcodeOffset table, just index into it.
2449 if (N.getOpcode() < OpcodeOffset.size())
2450 MatcherIndex = OpcodeOffset[N.getOpcode()];
2451 DEBUG(dbgs() << " Initial Opcode index to " << MatcherIndex << "\n");
2453 } else if (MatcherTable[0] == OPC_SwitchOpcode) {
2454 // Otherwise, the table isn't computed, but the state machine does start
2455 // with an OPC_SwitchOpcode instruction. Populate the table now, since this
2456 // is the first time we're selecting an instruction.
2459 // Get the size of this case.
2460 unsigned CaseSize = MatcherTable[Idx++];
2462 CaseSize = GetVBR(CaseSize, MatcherTable, Idx);
2463 if (CaseSize == 0) break;
2465 // Get the opcode, add the index to the table.
2466 uint16_t Opc = MatcherTable[Idx++];
2467 Opc |= (unsigned short)MatcherTable[Idx++] << 8;
2468 if (Opc >= OpcodeOffset.size())
2469 OpcodeOffset.resize((Opc+1)*2);
2470 OpcodeOffset[Opc] = Idx;
2474 // Okay, do the lookup for the first opcode.
2475 if (N.getOpcode() < OpcodeOffset.size())
2476 MatcherIndex = OpcodeOffset[N.getOpcode()];
2480 assert(MatcherIndex < TableSize && "Invalid index");
2482 unsigned CurrentOpcodeIndex = MatcherIndex;
2484 BuiltinOpcodes Opcode = (BuiltinOpcodes)MatcherTable[MatcherIndex++];
2487 // Okay, the semantics of this operation are that we should push a scope
2488 // then evaluate the first child. However, pushing a scope only to have
2489 // the first check fail (which then pops it) is inefficient. If we can
2490 // determine immediately that the first check (or first several) will
2491 // immediately fail, don't even bother pushing a scope for them.
2495 unsigned NumToSkip = MatcherTable[MatcherIndex++];
2496 if (NumToSkip & 128)
2497 NumToSkip = GetVBR(NumToSkip, MatcherTable, MatcherIndex);
2498 // Found the end of the scope with no match.
2499 if (NumToSkip == 0) {
2504 FailIndex = MatcherIndex+NumToSkip;
2506 unsigned MatcherIndexOfPredicate = MatcherIndex;
2507 (void)MatcherIndexOfPredicate; // silence warning.
2509 // If we can't evaluate this predicate without pushing a scope (e.g. if
2510 // it is a 'MoveParent') or if the predicate succeeds on this node, we
2511 // push the scope and evaluate the full predicate chain.
2513 MatcherIndex = IsPredicateKnownToFail(MatcherTable, MatcherIndex, N,
2514 Result, *this, RecordedNodes);
2518 DEBUG(dbgs() << " Skipped scope entry (due to false predicate) at "
2519 << "index " << MatcherIndexOfPredicate
2520 << ", continuing at " << FailIndex << "\n");
2521 ++NumDAGIselRetries;
2523 // Otherwise, we know that this case of the Scope is guaranteed to fail,
2524 // move to the next case.
2525 MatcherIndex = FailIndex;
2528 // If the whole scope failed to match, bail.
2529 if (FailIndex == 0) break;
2531 // Push a MatchScope which indicates where to go if the first child fails
2533 MatchScope NewEntry;
2534 NewEntry.FailIndex = FailIndex;
2535 NewEntry.NodeStack.append(NodeStack.begin(), NodeStack.end());
2536 NewEntry.NumRecordedNodes = RecordedNodes.size();
2537 NewEntry.NumMatchedMemRefs = MatchedMemRefs.size();
2538 NewEntry.InputChain = InputChain;
2539 NewEntry.InputGlue = InputGlue;
2540 NewEntry.HasChainNodesMatched = !ChainNodesMatched.empty();
2541 NewEntry.HasGlueResultNodesMatched = !GlueResultNodesMatched.empty();
2542 MatchScopes.push_back(NewEntry);
2545 case OPC_RecordNode: {
2546 // Remember this node, it may end up being an operand in the pattern.
2547 SDNode *Parent = nullptr;
2548 if (NodeStack.size() > 1)
2549 Parent = NodeStack[NodeStack.size()-2].getNode();
2550 RecordedNodes.push_back(std::make_pair(N, Parent));
2554 case OPC_RecordChild0: case OPC_RecordChild1:
2555 case OPC_RecordChild2: case OPC_RecordChild3:
2556 case OPC_RecordChild4: case OPC_RecordChild5:
2557 case OPC_RecordChild6: case OPC_RecordChild7: {
2558 unsigned ChildNo = Opcode-OPC_RecordChild0;
2559 if (ChildNo >= N.getNumOperands())
2560 break; // Match fails if out of range child #.
2562 RecordedNodes.push_back(std::make_pair(N->getOperand(ChildNo),
2566 case OPC_RecordMemRef:
2567 MatchedMemRefs.push_back(cast<MemSDNode>(N)->getMemOperand());
2570 case OPC_CaptureGlueInput:
2571 // If the current node has an input glue, capture it in InputGlue.
2572 if (N->getNumOperands() != 0 &&
2573 N->getOperand(N->getNumOperands()-1).getValueType() == MVT::Glue)
2574 InputGlue = N->getOperand(N->getNumOperands()-1);
2577 case OPC_MoveChild: {
2578 unsigned ChildNo = MatcherTable[MatcherIndex++];
2579 if (ChildNo >= N.getNumOperands())
2580 break; // Match fails if out of range child #.
2581 N = N.getOperand(ChildNo);
2582 NodeStack.push_back(N);
2586 case OPC_MoveParent:
2587 // Pop the current node off the NodeStack.
2588 NodeStack.pop_back();
2589 assert(!NodeStack.empty() && "Node stack imbalance!");
2590 N = NodeStack.back();
2594 if (!::CheckSame(MatcherTable, MatcherIndex, N, RecordedNodes)) break;
2597 case OPC_CheckChild0Same: case OPC_CheckChild1Same:
2598 case OPC_CheckChild2Same: case OPC_CheckChild3Same:
2599 if (!::CheckChildSame(MatcherTable, MatcherIndex, N, RecordedNodes,
2600 Opcode-OPC_CheckChild0Same))
2604 case OPC_CheckPatternPredicate:
2605 if (!::CheckPatternPredicate(MatcherTable, MatcherIndex, *this)) break;
2607 case OPC_CheckPredicate:
2608 if (!::CheckNodePredicate(MatcherTable, MatcherIndex, *this,
2612 case OPC_CheckComplexPat: {
2613 unsigned CPNum = MatcherTable[MatcherIndex++];
2614 unsigned RecNo = MatcherTable[MatcherIndex++];
2615 assert(RecNo < RecordedNodes.size() && "Invalid CheckComplexPat");
2616 if (!CheckComplexPattern(NodeToMatch, RecordedNodes[RecNo].second,
2617 RecordedNodes[RecNo].first, CPNum,
2622 case OPC_CheckOpcode:
2623 if (!::CheckOpcode(MatcherTable, MatcherIndex, N.getNode())) break;
2627 if (!::CheckType(MatcherTable, MatcherIndex, N, getTargetLowering()))
2631 case OPC_SwitchOpcode: {
2632 unsigned CurNodeOpcode = N.getOpcode();
2633 unsigned SwitchStart = MatcherIndex-1; (void)SwitchStart;
2636 // Get the size of this case.
2637 CaseSize = MatcherTable[MatcherIndex++];
2639 CaseSize = GetVBR(CaseSize, MatcherTable, MatcherIndex);
2640 if (CaseSize == 0) break;
2642 uint16_t Opc = MatcherTable[MatcherIndex++];
2643 Opc |= (unsigned short)MatcherTable[MatcherIndex++] << 8;
2645 // If the opcode matches, then we will execute this case.
2646 if (CurNodeOpcode == Opc)
2649 // Otherwise, skip over this case.
2650 MatcherIndex += CaseSize;
2653 // If no cases matched, bail out.
2654 if (CaseSize == 0) break;
2656 // Otherwise, execute the case we found.
2657 DEBUG(dbgs() << " OpcodeSwitch from " << SwitchStart
2658 << " to " << MatcherIndex << "\n");
2662 case OPC_SwitchType: {
2663 MVT CurNodeVT = N.getSimpleValueType();
2664 unsigned SwitchStart = MatcherIndex-1; (void)SwitchStart;
2667 // Get the size of this case.
2668 CaseSize = MatcherTable[MatcherIndex++];
2670 CaseSize = GetVBR(CaseSize, MatcherTable, MatcherIndex);
2671 if (CaseSize == 0) break;
2673 MVT CaseVT = (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2674 if (CaseVT == MVT::iPTR)
2675 CaseVT = getTargetLowering()->getPointerTy();
2677 // If the VT matches, then we will execute this case.
2678 if (CurNodeVT == CaseVT)
2681 // Otherwise, skip over this case.
2682 MatcherIndex += CaseSize;
2685 // If no cases matched, bail out.
2686 if (CaseSize == 0) break;
2688 // Otherwise, execute the case we found.
2689 DEBUG(dbgs() << " TypeSwitch[" << EVT(CurNodeVT).getEVTString()
2690 << "] from " << SwitchStart << " to " << MatcherIndex<<'\n');
2693 case OPC_CheckChild0Type: case OPC_CheckChild1Type:
2694 case OPC_CheckChild2Type: case OPC_CheckChild3Type:
2695 case OPC_CheckChild4Type: case OPC_CheckChild5Type:
2696 case OPC_CheckChild6Type: case OPC_CheckChild7Type:
2697 if (!::CheckChildType(MatcherTable, MatcherIndex, N, getTargetLowering(),
2698 Opcode-OPC_CheckChild0Type))
2701 case OPC_CheckCondCode:
2702 if (!::CheckCondCode(MatcherTable, MatcherIndex, N)) break;
2704 case OPC_CheckValueType:
2705 if (!::CheckValueType(MatcherTable, MatcherIndex, N, getTargetLowering()))
2708 case OPC_CheckInteger:
2709 if (!::CheckInteger(MatcherTable, MatcherIndex, N)) break;
2711 case OPC_CheckChild0Integer: case OPC_CheckChild1Integer:
2712 case OPC_CheckChild2Integer: case OPC_CheckChild3Integer:
2713 case OPC_CheckChild4Integer:
2714 if (!::CheckChildInteger(MatcherTable, MatcherIndex, N,
2715 Opcode-OPC_CheckChild0Integer)) break;
2717 case OPC_CheckAndImm:
2718 if (!::CheckAndImm(MatcherTable, MatcherIndex, N, *this)) break;
2720 case OPC_CheckOrImm:
2721 if (!::CheckOrImm(MatcherTable, MatcherIndex, N, *this)) break;
2724 case OPC_CheckFoldableChainNode: {
2725 assert(NodeStack.size() != 1 && "No parent node");
2726 // Verify that all intermediate nodes between the root and this one have
2728 bool HasMultipleUses = false;
2729 for (unsigned i = 1, e = NodeStack.size()-1; i != e; ++i)
2730 if (!NodeStack[i].hasOneUse()) {
2731 HasMultipleUses = true;
2734 if (HasMultipleUses) break;
2736 // Check to see that the target thinks this is profitable to fold and that
2737 // we can fold it without inducing cycles in the graph.
2738 if (!IsProfitableToFold(N, NodeStack[NodeStack.size()-2].getNode(),
2740 !IsLegalToFold(N, NodeStack[NodeStack.size()-2].getNode(),
2741 NodeToMatch, OptLevel,
2742 true/*We validate our own chains*/))
2747 case OPC_EmitInteger: {
2748 MVT::SimpleValueType VT =
2749 (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2750 int64_t Val = MatcherTable[MatcherIndex++];
2752 Val = GetVBR(Val, MatcherTable, MatcherIndex);
2753 RecordedNodes.push_back(std::pair<SDValue, SDNode*>(
2754 CurDAG->getTargetConstant(Val, VT), nullptr));
2757 case OPC_EmitRegister: {
2758 MVT::SimpleValueType VT =
2759 (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2760 unsigned RegNo = MatcherTable[MatcherIndex++];
2761 RecordedNodes.push_back(std::pair<SDValue, SDNode*>(
2762 CurDAG->getRegister(RegNo, VT), nullptr));
2765 case OPC_EmitRegister2: {
2766 // For targets w/ more than 256 register names, the register enum
2767 // values are stored in two bytes in the matcher table (just like
2769 MVT::SimpleValueType VT =
2770 (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2771 unsigned RegNo = MatcherTable[MatcherIndex++];
2772 RegNo |= MatcherTable[MatcherIndex++] << 8;
2773 RecordedNodes.push_back(std::pair<SDValue, SDNode*>(
2774 CurDAG->getRegister(RegNo, VT), nullptr));
2778 case OPC_EmitConvertToTarget: {
2779 // Convert from IMM/FPIMM to target version.
2780 unsigned RecNo = MatcherTable[MatcherIndex++];
2781 assert(RecNo < RecordedNodes.size() && "Invalid EmitConvertToTarget");
2782 SDValue Imm = RecordedNodes[RecNo].first;
2784 if (Imm->getOpcode() == ISD::Constant) {
2785 const ConstantInt *Val=cast<ConstantSDNode>(Imm)->getConstantIntValue();
2786 Imm = CurDAG->getConstant(*Val, Imm.getValueType(), true);
2787 } else if (Imm->getOpcode() == ISD::ConstantFP) {
2788 const ConstantFP *Val=cast<ConstantFPSDNode>(Imm)->getConstantFPValue();
2789 Imm = CurDAG->getConstantFP(*Val, Imm.getValueType(), true);
2792 RecordedNodes.push_back(std::make_pair(Imm, RecordedNodes[RecNo].second));
2796 case OPC_EmitMergeInputChains1_0: // OPC_EmitMergeInputChains, 1, 0
2797 case OPC_EmitMergeInputChains1_1: { // OPC_EmitMergeInputChains, 1, 1
2798 // These are space-optimized forms of OPC_EmitMergeInputChains.
2799 assert(!InputChain.getNode() &&
2800 "EmitMergeInputChains should be the first chain producing node");
2801 assert(ChainNodesMatched.empty() &&
2802 "Should only have one EmitMergeInputChains per match");
2804 // Read all of the chained nodes.
2805 unsigned RecNo = Opcode == OPC_EmitMergeInputChains1_1;
2806 assert(RecNo < RecordedNodes.size() && "Invalid EmitMergeInputChains");
2807 ChainNodesMatched.push_back(RecordedNodes[RecNo].first.getNode());
2809 // FIXME: What if other value results of the node have uses not matched
2811 if (ChainNodesMatched.back() != NodeToMatch &&
2812 !RecordedNodes[RecNo].first.hasOneUse()) {
2813 ChainNodesMatched.clear();
2817 // Merge the input chains if they are not intra-pattern references.
2818 InputChain = HandleMergeInputChains(ChainNodesMatched, CurDAG);
2820 if (!InputChain.getNode())
2821 break; // Failed to merge.
2825 case OPC_EmitMergeInputChains: {
2826 assert(!InputChain.getNode() &&
2827 "EmitMergeInputChains should be the first chain producing node");
2828 // This node gets a list of nodes we matched in the input that have
2829 // chains. We want to token factor all of the input chains to these nodes
2830 // together. However, if any of the input chains is actually one of the
2831 // nodes matched in this pattern, then we have an intra-match reference.
2832 // Ignore these because the newly token factored chain should not refer to
2834 unsigned NumChains = MatcherTable[MatcherIndex++];
2835 assert(NumChains != 0 && "Can't TF zero chains");
2837 assert(ChainNodesMatched.empty() &&
2838 "Should only have one EmitMergeInputChains per match");
2840 // Read all of the chained nodes.
2841 for (unsigned i = 0; i != NumChains; ++i) {
2842 unsigned RecNo = MatcherTable[MatcherIndex++];
2843 assert(RecNo < RecordedNodes.size() && "Invalid EmitMergeInputChains");
2844 ChainNodesMatched.push_back(RecordedNodes[RecNo].first.getNode());
2846 // FIXME: What if other value results of the node have uses not matched
2848 if (ChainNodesMatched.back() != NodeToMatch &&
2849 !RecordedNodes[RecNo].first.hasOneUse()) {
2850 ChainNodesMatched.clear();
2855 // If the inner loop broke out, the match fails.
2856 if (ChainNodesMatched.empty())
2859 // Merge the input chains if they are not intra-pattern references.
2860 InputChain = HandleMergeInputChains(ChainNodesMatched, CurDAG);
2862 if (!InputChain.getNode())
2863 break; // Failed to merge.
2868 case OPC_EmitCopyToReg: {
2869 unsigned RecNo = MatcherTable[MatcherIndex++];
2870 assert(RecNo < RecordedNodes.size() && "Invalid EmitCopyToReg");
2871 unsigned DestPhysReg = MatcherTable[MatcherIndex++];
2873 if (!InputChain.getNode())
2874 InputChain = CurDAG->getEntryNode();
2876 InputChain = CurDAG->getCopyToReg(InputChain, SDLoc(NodeToMatch),
2877 DestPhysReg, RecordedNodes[RecNo].first,
2880 InputGlue = InputChain.getValue(1);
2884 case OPC_EmitNodeXForm: {
2885 unsigned XFormNo = MatcherTable[MatcherIndex++];
2886 unsigned RecNo = MatcherTable[MatcherIndex++];
2887 assert(RecNo < RecordedNodes.size() && "Invalid EmitNodeXForm");
2888 SDValue Res = RunSDNodeXForm(RecordedNodes[RecNo].first, XFormNo);
2889 RecordedNodes.push_back(std::pair<SDValue,SDNode*>(Res, nullptr));
2894 case OPC_MorphNodeTo: {
2895 uint16_t TargetOpc = MatcherTable[MatcherIndex++];
2896 TargetOpc |= (unsigned short)MatcherTable[MatcherIndex++] << 8;
2897 unsigned EmitNodeInfo = MatcherTable[MatcherIndex++];
2898 // Get the result VT list.
2899 unsigned NumVTs = MatcherTable[MatcherIndex++];
2900 SmallVector<EVT, 4> VTs;
2901 for (unsigned i = 0; i != NumVTs; ++i) {
2902 MVT::SimpleValueType VT =
2903 (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2904 if (VT == MVT::iPTR) VT = getTargetLowering()->getPointerTy().SimpleTy;
2908 if (EmitNodeInfo & OPFL_Chain)
2909 VTs.push_back(MVT::Other);
2910 if (EmitNodeInfo & OPFL_GlueOutput)
2911 VTs.push_back(MVT::Glue);
2913 // This is hot code, so optimize the two most common cases of 1 and 2
2916 if (VTs.size() == 1)
2917 VTList = CurDAG->getVTList(VTs[0]);
2918 else if (VTs.size() == 2)
2919 VTList = CurDAG->getVTList(VTs[0], VTs[1]);
2921 VTList = CurDAG->getVTList(VTs);
2923 // Get the operand list.
2924 unsigned NumOps = MatcherTable[MatcherIndex++];
2925 SmallVector<SDValue, 8> Ops;
2926 for (unsigned i = 0; i != NumOps; ++i) {
2927 unsigned RecNo = MatcherTable[MatcherIndex++];
2929 RecNo = GetVBR(RecNo, MatcherTable, MatcherIndex);
2931 assert(RecNo < RecordedNodes.size() && "Invalid EmitNode");
2932 Ops.push_back(RecordedNodes[RecNo].first);
2935 // If there are variadic operands to add, handle them now.
2936 if (EmitNodeInfo & OPFL_VariadicInfo) {
2937 // Determine the start index to copy from.
2938 unsigned FirstOpToCopy = getNumFixedFromVariadicInfo(EmitNodeInfo);
2939 FirstOpToCopy += (EmitNodeInfo & OPFL_Chain) ? 1 : 0;
2940 assert(NodeToMatch->getNumOperands() >= FirstOpToCopy &&
2941 "Invalid variadic node");
2942 // Copy all of the variadic operands, not including a potential glue
2944 for (unsigned i = FirstOpToCopy, e = NodeToMatch->getNumOperands();
2946 SDValue V = NodeToMatch->getOperand(i);
2947 if (V.getValueType() == MVT::Glue) break;
2952 // If this has chain/glue inputs, add them.
2953 if (EmitNodeInfo & OPFL_Chain)
2954 Ops.push_back(InputChain);
2955 if ((EmitNodeInfo & OPFL_GlueInput) && InputGlue.getNode() != nullptr)
2956 Ops.push_back(InputGlue);
2959 SDNode *Res = nullptr;
2960 if (Opcode != OPC_MorphNodeTo) {
2961 // If this is a normal EmitNode command, just create the new node and
2962 // add the results to the RecordedNodes list.
2963 Res = CurDAG->getMachineNode(TargetOpc, SDLoc(NodeToMatch),
2966 // Add all the non-glue/non-chain results to the RecordedNodes list.
2967 for (unsigned i = 0, e = VTs.size(); i != e; ++i) {
2968 if (VTs[i] == MVT::Other || VTs[i] == MVT::Glue) break;
2969 RecordedNodes.push_back(std::pair<SDValue,SDNode*>(SDValue(Res, i),
2973 } else if (NodeToMatch->getOpcode() != ISD::DELETED_NODE) {
2974 Res = MorphNode(NodeToMatch, TargetOpc, VTList, Ops, EmitNodeInfo);
2976 // NodeToMatch was eliminated by CSE when the target changed the DAG.
2977 // We will visit the equivalent node later.
2978 DEBUG(dbgs() << "Node was eliminated by CSE\n");
2982 // If the node had chain/glue results, update our notion of the current
2984 if (EmitNodeInfo & OPFL_GlueOutput) {
2985 InputGlue = SDValue(Res, VTs.size()-1);
2986 if (EmitNodeInfo & OPFL_Chain)
2987 InputChain = SDValue(Res, VTs.size()-2);
2988 } else if (EmitNodeInfo & OPFL_Chain)
2989 InputChain = SDValue(Res, VTs.size()-1);
2991 // If the OPFL_MemRefs glue is set on this node, slap all of the
2992 // accumulated memrefs onto it.
2994 // FIXME: This is vastly incorrect for patterns with multiple outputs
2995 // instructions that access memory and for ComplexPatterns that match
2997 if (EmitNodeInfo & OPFL_MemRefs) {
2998 // Only attach load or store memory operands if the generated
2999 // instruction may load or store.
3000 const MCInstrDesc &MCID = TM.getInstrInfo()->get(TargetOpc);
3001 bool mayLoad = MCID.mayLoad();
3002 bool mayStore = MCID.mayStore();
3004 unsigned NumMemRefs = 0;
3005 for (SmallVectorImpl<MachineMemOperand *>::const_iterator I =
3006 MatchedMemRefs.begin(), E = MatchedMemRefs.end(); I != E; ++I) {
3007 if ((*I)->isLoad()) {
3010 } else if ((*I)->isStore()) {
3018 MachineSDNode::mmo_iterator MemRefs =
3019 MF->allocateMemRefsArray(NumMemRefs);
3021 MachineSDNode::mmo_iterator MemRefsPos = MemRefs;
3022 for (SmallVectorImpl<MachineMemOperand *>::const_iterator I =
3023 MatchedMemRefs.begin(), E = MatchedMemRefs.end(); I != E; ++I) {
3024 if ((*I)->isLoad()) {
3027 } else if ((*I)->isStore()) {
3035 cast<MachineSDNode>(Res)
3036 ->setMemRefs(MemRefs, MemRefs + NumMemRefs);
3040 << (Opcode == OPC_MorphNodeTo ? "Morphed" : "Created")
3041 << " node: "; Res->dump(CurDAG); dbgs() << "\n");
3043 // If this was a MorphNodeTo then we're completely done!
3044 if (Opcode == OPC_MorphNodeTo) {
3045 // Update chain and glue uses.
3046 UpdateChainsAndGlue(NodeToMatch, InputChain, ChainNodesMatched,
3047 InputGlue, GlueResultNodesMatched, true);
3054 case OPC_MarkGlueResults: {
3055 unsigned NumNodes = MatcherTable[MatcherIndex++];
3057 // Read and remember all the glue-result nodes.
3058 for (unsigned i = 0; i != NumNodes; ++i) {
3059 unsigned RecNo = MatcherTable[MatcherIndex++];
3061 RecNo = GetVBR(RecNo, MatcherTable, MatcherIndex);
3063 assert(RecNo < RecordedNodes.size() && "Invalid MarkGlueResults");
3064 GlueResultNodesMatched.push_back(RecordedNodes[RecNo].first.getNode());
3069 case OPC_CompleteMatch: {
3070 // The match has been completed, and any new nodes (if any) have been
3071 // created. Patch up references to the matched dag to use the newly
3073 unsigned NumResults = MatcherTable[MatcherIndex++];
3075 for (unsigned i = 0; i != NumResults; ++i) {
3076 unsigned ResSlot = MatcherTable[MatcherIndex++];
3078 ResSlot = GetVBR(ResSlot, MatcherTable, MatcherIndex);
3080 assert(ResSlot < RecordedNodes.size() && "Invalid CompleteMatch");
3081 SDValue Res = RecordedNodes[ResSlot].first;
3083 assert(i < NodeToMatch->getNumValues() &&
3084 NodeToMatch->getValueType(i) != MVT::Other &&
3085 NodeToMatch->getValueType(i) != MVT::Glue &&
3086 "Invalid number of results to complete!");
3087 assert((NodeToMatch->getValueType(i) == Res.getValueType() ||
3088 NodeToMatch->getValueType(i) == MVT::iPTR ||
3089 Res.getValueType() == MVT::iPTR ||
3090 NodeToMatch->getValueType(i).getSizeInBits() ==
3091 Res.getValueType().getSizeInBits()) &&
3092 "invalid replacement");
3093 CurDAG->ReplaceAllUsesOfValueWith(SDValue(NodeToMatch, i), Res);
3096 // If the root node defines glue, add it to the glue nodes to update list.
3097 if (NodeToMatch->getValueType(NodeToMatch->getNumValues()-1) == MVT::Glue)
3098 GlueResultNodesMatched.push_back(NodeToMatch);
3100 // Update chain and glue uses.
3101 UpdateChainsAndGlue(NodeToMatch, InputChain, ChainNodesMatched,
3102 InputGlue, GlueResultNodesMatched, false);
3104 assert(NodeToMatch->use_empty() &&
3105 "Didn't replace all uses of the node?");
3107 // FIXME: We just return here, which interacts correctly with SelectRoot
3108 // above. We should fix this to not return an SDNode* anymore.
3113 // If the code reached this point, then the match failed. See if there is
3114 // another child to try in the current 'Scope', otherwise pop it until we
3115 // find a case to check.
3116 DEBUG(dbgs() << " Match failed at index " << CurrentOpcodeIndex << "\n");
3117 ++NumDAGIselRetries;
3119 if (MatchScopes.empty()) {
3120 CannotYetSelect(NodeToMatch);
3124 // Restore the interpreter state back to the point where the scope was
3126 MatchScope &LastScope = MatchScopes.back();
3127 RecordedNodes.resize(LastScope.NumRecordedNodes);
3129 NodeStack.append(LastScope.NodeStack.begin(), LastScope.NodeStack.end());
3130 N = NodeStack.back();
3132 if (LastScope.NumMatchedMemRefs != MatchedMemRefs.size())
3133 MatchedMemRefs.resize(LastScope.NumMatchedMemRefs);
3134 MatcherIndex = LastScope.FailIndex;
3136 DEBUG(dbgs() << " Continuing at " << MatcherIndex << "\n");
3138 InputChain = LastScope.InputChain;
3139 InputGlue = LastScope.InputGlue;
3140 if (!LastScope.HasChainNodesMatched)
3141 ChainNodesMatched.clear();
3142 if (!LastScope.HasGlueResultNodesMatched)
3143 GlueResultNodesMatched.clear();
3145 // Check to see what the offset is at the new MatcherIndex. If it is zero
3146 // we have reached the end of this scope, otherwise we have another child
3147 // in the current scope to try.
3148 unsigned NumToSkip = MatcherTable[MatcherIndex++];
3149 if (NumToSkip & 128)
3150 NumToSkip = GetVBR(NumToSkip, MatcherTable, MatcherIndex);
3152 // If we have another child in this scope to match, update FailIndex and
3154 if (NumToSkip != 0) {
3155 LastScope.FailIndex = MatcherIndex+NumToSkip;
3159 // End of this scope, pop it and try the next child in the containing
3161 MatchScopes.pop_back();
3168 void SelectionDAGISel::CannotYetSelect(SDNode *N) {
3170 raw_string_ostream Msg(msg);
3171 Msg << "Cannot select: ";
3173 if (N->getOpcode() != ISD::INTRINSIC_W_CHAIN &&
3174 N->getOpcode() != ISD::INTRINSIC_WO_CHAIN &&
3175 N->getOpcode() != ISD::INTRINSIC_VOID) {
3176 N->printrFull(Msg, CurDAG);
3177 Msg << "\nIn function: " << MF->getName();
3179 bool HasInputChain = N->getOperand(0).getValueType() == MVT::Other;
3181 cast<ConstantSDNode>(N->getOperand(HasInputChain))->getZExtValue();
3182 if (iid < Intrinsic::num_intrinsics)
3183 Msg << "intrinsic %" << Intrinsic::getName((Intrinsic::ID)iid);
3184 else if (const TargetIntrinsicInfo *TII = TM.getIntrinsicInfo())
3185 Msg << "target intrinsic %" << TII->getName(iid);
3187 Msg << "unknown intrinsic #" << iid;
3189 report_fatal_error(Msg.str());
3192 char SelectionDAGISel::ID = 0;