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");
145 // Intrinsic instructions...
146 STATISTIC(NumFastIselFailIntrinsicCall, "Fast isel fails on Intrinsic call");
147 STATISTIC(NumFastIselFailSAddWithOverflow,
148 "Fast isel fails on sadd.with.overflow");
149 STATISTIC(NumFastIselFailUAddWithOverflow,
150 "Fast isel fails on uadd.with.overflow");
151 STATISTIC(NumFastIselFailSSubWithOverflow,
152 "Fast isel fails on ssub.with.overflow");
153 STATISTIC(NumFastIselFailUSubWithOverflow,
154 "Fast isel fails on usub.with.overflow");
155 STATISTIC(NumFastIselFailSMulWithOverflow,
156 "Fast isel fails on smul.with.overflow");
157 STATISTIC(NumFastIselFailUMulWithOverflow,
158 "Fast isel fails on umul.with.overflow");
159 STATISTIC(NumFastIselFailFrameaddress, "Fast isel fails on Frameaddress");
160 STATISTIC(NumFastIselFailSqrt, "Fast isel fails on sqrt call");
161 STATISTIC(NumFastIselFailStackMap, "Fast isel fails on StackMap call");
162 STATISTIC(NumFastIselFailPatchPoint, "Fast isel fails on PatchPoint call");
166 EnableFastISelVerbose("fast-isel-verbose", cl::Hidden,
167 cl::desc("Enable verbose messages in the \"fast\" "
168 "instruction selector"));
170 EnableFastISelAbort("fast-isel-abort", cl::Hidden,
171 cl::desc("Enable abort calls when \"fast\" instruction selection "
172 "fails to lower an instruction"));
174 EnableFastISelAbortArgs("fast-isel-abort-args", cl::Hidden,
175 cl::desc("Enable abort calls when \"fast\" instruction selection "
176 "fails to lower a formal argument"));
180 cl::desc("use Machine Branch Probability Info"),
181 cl::init(true), cl::Hidden);
185 ViewDAGCombine1("view-dag-combine1-dags", cl::Hidden,
186 cl::desc("Pop up a window to show dags before the first "
187 "dag combine pass"));
189 ViewLegalizeTypesDAGs("view-legalize-types-dags", cl::Hidden,
190 cl::desc("Pop up a window to show dags before legalize types"));
192 ViewLegalizeDAGs("view-legalize-dags", cl::Hidden,
193 cl::desc("Pop up a window to show dags before legalize"));
195 ViewDAGCombine2("view-dag-combine2-dags", cl::Hidden,
196 cl::desc("Pop up a window to show dags before the second "
197 "dag combine pass"));
199 ViewDAGCombineLT("view-dag-combine-lt-dags", cl::Hidden,
200 cl::desc("Pop up a window to show dags before the post legalize types"
201 " dag combine pass"));
203 ViewISelDAGs("view-isel-dags", cl::Hidden,
204 cl::desc("Pop up a window to show isel dags as they are selected"));
206 ViewSchedDAGs("view-sched-dags", cl::Hidden,
207 cl::desc("Pop up a window to show sched dags as they are processed"));
209 ViewSUnitDAGs("view-sunit-dags", cl::Hidden,
210 cl::desc("Pop up a window to show SUnit dags after they are processed"));
212 static const bool ViewDAGCombine1 = false,
213 ViewLegalizeTypesDAGs = false, ViewLegalizeDAGs = false,
214 ViewDAGCombine2 = false,
215 ViewDAGCombineLT = false,
216 ViewISelDAGs = false, ViewSchedDAGs = false,
217 ViewSUnitDAGs = false;
220 //===---------------------------------------------------------------------===//
222 /// RegisterScheduler class - Track the registration of instruction schedulers.
224 //===---------------------------------------------------------------------===//
225 MachinePassRegistry RegisterScheduler::Registry;
227 //===---------------------------------------------------------------------===//
229 /// ISHeuristic command line option for instruction schedulers.
231 //===---------------------------------------------------------------------===//
232 static cl::opt<RegisterScheduler::FunctionPassCtor, false,
233 RegisterPassParser<RegisterScheduler> >
234 ISHeuristic("pre-RA-sched",
235 cl::init(&createDefaultScheduler), cl::Hidden,
236 cl::desc("Instruction schedulers available (before register"
239 static RegisterScheduler
240 defaultListDAGScheduler("default", "Best scheduler for the target",
241 createDefaultScheduler);
244 //===--------------------------------------------------------------------===//
245 /// \brief This class is used by SelectionDAGISel to temporarily override
246 /// the optimization level on a per-function basis.
247 class OptLevelChanger {
248 SelectionDAGISel &IS;
249 CodeGenOpt::Level SavedOptLevel;
253 OptLevelChanger(SelectionDAGISel &ISel,
254 CodeGenOpt::Level NewOptLevel) : IS(ISel) {
255 SavedOptLevel = IS.OptLevel;
256 if (NewOptLevel == SavedOptLevel)
258 IS.OptLevel = NewOptLevel;
259 IS.TM.setOptLevel(NewOptLevel);
260 SavedFastISel = IS.TM.Options.EnableFastISel;
261 if (NewOptLevel == CodeGenOpt::None)
262 IS.TM.setFastISel(true);
263 DEBUG(dbgs() << "\nChanging optimization level for Function "
264 << IS.MF->getFunction()->getName() << "\n");
265 DEBUG(dbgs() << "\tBefore: -O" << SavedOptLevel
266 << " ; After: -O" << NewOptLevel << "\n");
270 if (IS.OptLevel == SavedOptLevel)
272 DEBUG(dbgs() << "\nRestoring optimization level for Function "
273 << IS.MF->getFunction()->getName() << "\n");
274 DEBUG(dbgs() << "\tBefore: -O" << IS.OptLevel
275 << " ; After: -O" << SavedOptLevel << "\n");
276 IS.OptLevel = SavedOptLevel;
277 IS.TM.setOptLevel(SavedOptLevel);
278 IS.TM.setFastISel(SavedFastISel);
282 //===--------------------------------------------------------------------===//
283 /// createDefaultScheduler - This creates an instruction scheduler appropriate
285 ScheduleDAGSDNodes* createDefaultScheduler(SelectionDAGISel *IS,
286 CodeGenOpt::Level OptLevel) {
287 const TargetLowering *TLI = IS->getTargetLowering();
288 const TargetSubtargetInfo &ST = IS->TM.getSubtarget<TargetSubtargetInfo>();
290 if (OptLevel == CodeGenOpt::None || ST.useMachineScheduler() ||
291 TLI->getSchedulingPreference() == Sched::Source)
292 return createSourceListDAGScheduler(IS, OptLevel);
293 if (TLI->getSchedulingPreference() == Sched::RegPressure)
294 return createBURRListDAGScheduler(IS, OptLevel);
295 if (TLI->getSchedulingPreference() == Sched::Hybrid)
296 return createHybridListDAGScheduler(IS, OptLevel);
297 if (TLI->getSchedulingPreference() == Sched::VLIW)
298 return createVLIWDAGScheduler(IS, OptLevel);
299 assert(TLI->getSchedulingPreference() == Sched::ILP &&
300 "Unknown sched type!");
301 return createILPListDAGScheduler(IS, OptLevel);
305 // EmitInstrWithCustomInserter - This method should be implemented by targets
306 // that mark instructions with the 'usesCustomInserter' flag. These
307 // instructions are special in various ways, which require special support to
308 // insert. The specified MachineInstr is created but not inserted into any
309 // basic blocks, and this method is called to expand it into a sequence of
310 // instructions, potentially also creating new basic blocks and control flow.
311 // When new basic blocks are inserted and the edges from MBB to its successors
312 // are modified, the method should insert pairs of <OldSucc, NewSucc> into the
315 TargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
316 MachineBasicBlock *MBB) const {
318 dbgs() << "If a target marks an instruction with "
319 "'usesCustomInserter', it must implement "
320 "TargetLowering::EmitInstrWithCustomInserter!";
322 llvm_unreachable(nullptr);
325 void TargetLowering::AdjustInstrPostInstrSelection(MachineInstr *MI,
326 SDNode *Node) const {
327 assert(!MI->hasPostISelHook() &&
328 "If a target marks an instruction with 'hasPostISelHook', "
329 "it must implement TargetLowering::AdjustInstrPostInstrSelection!");
332 //===----------------------------------------------------------------------===//
333 // SelectionDAGISel code
334 //===----------------------------------------------------------------------===//
336 SelectionDAGISel::SelectionDAGISel(TargetMachine &tm,
337 CodeGenOpt::Level OL) :
338 MachineFunctionPass(ID), TM(tm),
339 FuncInfo(new FunctionLoweringInfo(TM)),
340 CurDAG(new SelectionDAG(tm, OL)),
341 SDB(new SelectionDAGBuilder(*CurDAG, *FuncInfo, OL)),
345 initializeGCModuleInfoPass(*PassRegistry::getPassRegistry());
346 initializeAliasAnalysisAnalysisGroup(*PassRegistry::getPassRegistry());
347 initializeBranchProbabilityInfoPass(*PassRegistry::getPassRegistry());
348 initializeTargetLibraryInfoPass(*PassRegistry::getPassRegistry());
351 SelectionDAGISel::~SelectionDAGISel() {
357 void SelectionDAGISel::getAnalysisUsage(AnalysisUsage &AU) const {
358 AU.addRequired<AliasAnalysis>();
359 AU.addPreserved<AliasAnalysis>();
360 AU.addRequired<GCModuleInfo>();
361 AU.addPreserved<GCModuleInfo>();
362 AU.addRequired<TargetLibraryInfo>();
363 if (UseMBPI && OptLevel != CodeGenOpt::None)
364 AU.addRequired<BranchProbabilityInfo>();
365 MachineFunctionPass::getAnalysisUsage(AU);
368 /// SplitCriticalSideEffectEdges - Look for critical edges with a PHI value that
369 /// may trap on it. In this case we have to split the edge so that the path
370 /// through the predecessor block that doesn't go to the phi block doesn't
371 /// execute the possibly trapping instruction.
373 /// This is required for correctness, so it must be done at -O0.
375 static void SplitCriticalSideEffectEdges(Function &Fn, Pass *SDISel) {
376 // Loop for blocks with phi nodes.
377 for (Function::iterator BB = Fn.begin(), E = Fn.end(); BB != E; ++BB) {
378 PHINode *PN = dyn_cast<PHINode>(BB->begin());
382 // For each block with a PHI node, check to see if any of the input values
383 // are potentially trapping constant expressions. Constant expressions are
384 // the only potentially trapping value that can occur as the argument to a
386 for (BasicBlock::iterator I = BB->begin(); (PN = dyn_cast<PHINode>(I)); ++I)
387 for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
388 ConstantExpr *CE = dyn_cast<ConstantExpr>(PN->getIncomingValue(i));
389 if (!CE || !CE->canTrap()) continue;
391 // The only case we have to worry about is when the edge is critical.
392 // Since this block has a PHI Node, we assume it has multiple input
393 // edges: check to see if the pred has multiple successors.
394 BasicBlock *Pred = PN->getIncomingBlock(i);
395 if (Pred->getTerminator()->getNumSuccessors() == 1)
398 // Okay, we have to split this edge.
399 SplitCriticalEdge(Pred->getTerminator(),
400 GetSuccessorNumber(Pred, BB), SDISel, true);
406 bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
407 // Do some sanity-checking on the command-line options.
408 assert((!EnableFastISelVerbose || TM.Options.EnableFastISel) &&
409 "-fast-isel-verbose requires -fast-isel");
410 assert((!EnableFastISelAbort || TM.Options.EnableFastISel) &&
411 "-fast-isel-abort requires -fast-isel");
413 const Function &Fn = *mf.getFunction();
414 const TargetInstrInfo &TII = *TM.getSubtargetImpl()->getInstrInfo();
415 const TargetRegisterInfo &TRI = *TM.getSubtargetImpl()->getRegisterInfo();
416 const TargetLowering *TLI = TM.getSubtargetImpl()->getTargetLowering();
419 RegInfo = &MF->getRegInfo();
420 AA = &getAnalysis<AliasAnalysis>();
421 LibInfo = &getAnalysis<TargetLibraryInfo>();
422 GFI = Fn.hasGC() ? &getAnalysis<GCModuleInfo>().getFunctionInfo(Fn) : nullptr;
424 TM.resetTargetOptions(Fn);
426 // Reset OptLevel to None for optnone functions.
427 CodeGenOpt::Level NewOptLevel = OptLevel;
428 if (Fn.hasFnAttribute(Attribute::OptimizeNone))
429 NewOptLevel = CodeGenOpt::None;
430 OptLevelChanger OLC(*this, NewOptLevel);
432 DEBUG(dbgs() << "\n\n\n=== " << Fn.getName() << "\n");
434 SplitCriticalSideEffectEdges(const_cast<Function&>(Fn), this);
436 CurDAG->init(*MF, TLI);
437 FuncInfo->set(Fn, *MF, CurDAG);
439 if (UseMBPI && OptLevel != CodeGenOpt::None)
440 FuncInfo->BPI = &getAnalysis<BranchProbabilityInfo>();
442 FuncInfo->BPI = nullptr;
444 SDB->init(GFI, *AA, LibInfo);
446 MF->setHasInlineAsm(false);
448 SelectAllBasicBlocks(Fn);
450 // If the first basic block in the function has live ins that need to be
451 // copied into vregs, emit the copies into the top of the block before
452 // emitting the code for the block.
453 MachineBasicBlock *EntryMBB = MF->begin();
454 RegInfo->EmitLiveInCopies(EntryMBB, TRI, TII);
456 DenseMap<unsigned, unsigned> LiveInMap;
457 if (!FuncInfo->ArgDbgValues.empty())
458 for (MachineRegisterInfo::livein_iterator LI = RegInfo->livein_begin(),
459 E = RegInfo->livein_end(); LI != E; ++LI)
461 LiveInMap.insert(std::make_pair(LI->first, LI->second));
463 // Insert DBG_VALUE instructions for function arguments to the entry block.
464 for (unsigned i = 0, e = FuncInfo->ArgDbgValues.size(); i != e; ++i) {
465 MachineInstr *MI = FuncInfo->ArgDbgValues[e-i-1];
466 bool hasFI = MI->getOperand(0).isFI();
468 hasFI ? TRI.getFrameRegister(*MF) : MI->getOperand(0).getReg();
469 if (TargetRegisterInfo::isPhysicalRegister(Reg))
470 EntryMBB->insert(EntryMBB->begin(), MI);
472 MachineInstr *Def = RegInfo->getVRegDef(Reg);
474 MachineBasicBlock::iterator InsertPos = Def;
475 // FIXME: VR def may not be in entry block.
476 Def->getParent()->insert(std::next(InsertPos), MI);
478 DEBUG(dbgs() << "Dropping debug info for dead vreg"
479 << TargetRegisterInfo::virtReg2Index(Reg) << "\n");
482 // If Reg is live-in then update debug info to track its copy in a vreg.
483 DenseMap<unsigned, unsigned>::iterator LDI = LiveInMap.find(Reg);
484 if (LDI != LiveInMap.end()) {
485 assert(!hasFI && "There's no handling of frame pointer updating here yet "
487 MachineInstr *Def = RegInfo->getVRegDef(LDI->second);
488 MachineBasicBlock::iterator InsertPos = Def;
489 const MDNode *Variable = MI->getDebugVariable();
490 const MDNode *Expr = MI->getDebugExpression();
491 bool IsIndirect = MI->isIndirectDebugValue();
492 unsigned Offset = IsIndirect ? MI->getOperand(1).getImm() : 0;
493 // Def is never a terminator here, so it is ok to increment InsertPos.
494 BuildMI(*EntryMBB, ++InsertPos, MI->getDebugLoc(),
495 TII.get(TargetOpcode::DBG_VALUE), IsIndirect, LDI->second, Offset,
498 // If this vreg is directly copied into an exported register then
499 // that COPY instructions also need DBG_VALUE, if it is the only
500 // user of LDI->second.
501 MachineInstr *CopyUseMI = nullptr;
502 for (MachineRegisterInfo::use_instr_iterator
503 UI = RegInfo->use_instr_begin(LDI->second),
504 E = RegInfo->use_instr_end(); UI != E; ) {
505 MachineInstr *UseMI = &*(UI++);
506 if (UseMI->isDebugValue()) continue;
507 if (UseMI->isCopy() && !CopyUseMI && UseMI->getParent() == EntryMBB) {
508 CopyUseMI = UseMI; continue;
510 // Otherwise this is another use or second copy use.
511 CopyUseMI = nullptr; break;
514 MachineInstr *NewMI =
515 BuildMI(*MF, CopyUseMI->getDebugLoc(),
516 TII.get(TargetOpcode::DBG_VALUE), IsIndirect,
517 CopyUseMI->getOperand(0).getReg(), Offset, Variable, Expr);
518 MachineBasicBlock::iterator Pos = CopyUseMI;
519 EntryMBB->insertAfter(Pos, NewMI);
524 // Determine if there are any calls in this machine function.
525 MachineFrameInfo *MFI = MF->getFrameInfo();
526 for (const auto &MBB : *MF) {
527 if (MFI->hasCalls() && MF->hasInlineAsm())
530 for (const auto &MI : MBB) {
531 const MCInstrDesc &MCID =
532 TM.getSubtargetImpl()->getInstrInfo()->get(MI.getOpcode());
533 if ((MCID.isCall() && !MCID.isReturn()) ||
534 MI.isStackAligningInlineAsm()) {
535 MFI->setHasCalls(true);
537 if (MI.isInlineAsm()) {
538 MF->setHasInlineAsm(true);
543 // Determine if there is a call to setjmp in the machine function.
544 MF->setExposesReturnsTwice(Fn.callsFunctionThatReturnsTwice());
546 // Replace forward-declared registers with the registers containing
547 // the desired value.
548 MachineRegisterInfo &MRI = MF->getRegInfo();
549 for (DenseMap<unsigned, unsigned>::iterator
550 I = FuncInfo->RegFixups.begin(), E = FuncInfo->RegFixups.end();
552 unsigned From = I->first;
553 unsigned To = I->second;
554 // If To is also scheduled to be replaced, find what its ultimate
557 DenseMap<unsigned, unsigned>::iterator J = FuncInfo->RegFixups.find(To);
561 // Make sure the new register has a sufficiently constrained register class.
562 if (TargetRegisterInfo::isVirtualRegister(From) &&
563 TargetRegisterInfo::isVirtualRegister(To))
564 MRI.constrainRegClass(To, MRI.getRegClass(From));
566 MRI.replaceRegWith(From, To);
569 // Freeze the set of reserved registers now that MachineFrameInfo has been
570 // set up. All the information required by getReservedRegs() should be
572 MRI.freezeReservedRegs(*MF);
574 // Release function-specific state. SDB and CurDAG are already cleared
578 DEBUG(dbgs() << "*** MachineFunction at end of ISel ***\n");
579 DEBUG(MF->print(dbgs()));
584 void SelectionDAGISel::SelectBasicBlock(BasicBlock::const_iterator Begin,
585 BasicBlock::const_iterator End,
587 // Lower all of the non-terminator instructions. If a call is emitted
588 // as a tail call, cease emitting nodes for this block. Terminators
589 // are handled below.
590 for (BasicBlock::const_iterator I = Begin; I != End && !SDB->HasTailCall; ++I)
593 // Make sure the root of the DAG is up-to-date.
594 CurDAG->setRoot(SDB->getControlRoot());
595 HadTailCall = SDB->HasTailCall;
598 // Final step, emit the lowered DAG as machine code.
602 void SelectionDAGISel::ComputeLiveOutVRegInfo() {
603 SmallPtrSet<SDNode*, 128> VisitedNodes;
604 SmallVector<SDNode*, 128> Worklist;
606 Worklist.push_back(CurDAG->getRoot().getNode());
612 SDNode *N = Worklist.pop_back_val();
614 // If we've already seen this node, ignore it.
615 if (!VisitedNodes.insert(N))
618 // Otherwise, add all chain operands to the worklist.
619 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
620 if (N->getOperand(i).getValueType() == MVT::Other)
621 Worklist.push_back(N->getOperand(i).getNode());
623 // If this is a CopyToReg with a vreg dest, process it.
624 if (N->getOpcode() != ISD::CopyToReg)
627 unsigned DestReg = cast<RegisterSDNode>(N->getOperand(1))->getReg();
628 if (!TargetRegisterInfo::isVirtualRegister(DestReg))
631 // Ignore non-scalar or non-integer values.
632 SDValue Src = N->getOperand(2);
633 EVT SrcVT = Src.getValueType();
634 if (!SrcVT.isInteger() || SrcVT.isVector())
637 unsigned NumSignBits = CurDAG->ComputeNumSignBits(Src);
638 CurDAG->computeKnownBits(Src, KnownZero, KnownOne);
639 FuncInfo->AddLiveOutRegInfo(DestReg, NumSignBits, KnownZero, KnownOne);
640 } while (!Worklist.empty());
643 void SelectionDAGISel::CodeGenAndEmitDAG() {
644 std::string GroupName;
645 if (TimePassesIsEnabled)
646 GroupName = "Instruction Selection and Scheduling";
647 std::string BlockName;
648 int BlockNumber = -1;
651 if (ViewDAGCombine1 || ViewLegalizeTypesDAGs || ViewLegalizeDAGs ||
652 ViewDAGCombine2 || ViewDAGCombineLT || ViewISelDAGs || ViewSchedDAGs ||
656 BlockNumber = FuncInfo->MBB->getNumber();
657 BlockName = MF->getName().str() + ":" +
658 FuncInfo->MBB->getBasicBlock()->getName().str();
660 DEBUG(dbgs() << "Initial selection DAG: BB#" << BlockNumber
661 << " '" << BlockName << "'\n"; CurDAG->dump());
663 if (ViewDAGCombine1) CurDAG->viewGraph("dag-combine1 input for " + BlockName);
665 // Run the DAG combiner in pre-legalize mode.
667 NamedRegionTimer T("DAG Combining 1", GroupName, TimePassesIsEnabled);
668 CurDAG->Combine(BeforeLegalizeTypes, *AA, OptLevel);
671 DEBUG(dbgs() << "Optimized lowered selection DAG: BB#" << BlockNumber
672 << " '" << BlockName << "'\n"; CurDAG->dump());
674 // Second step, hack on the DAG until it only uses operations and types that
675 // the target supports.
676 if (ViewLegalizeTypesDAGs) CurDAG->viewGraph("legalize-types input for " +
681 NamedRegionTimer T("Type Legalization", GroupName, TimePassesIsEnabled);
682 Changed = CurDAG->LegalizeTypes();
685 DEBUG(dbgs() << "Type-legalized selection DAG: BB#" << BlockNumber
686 << " '" << BlockName << "'\n"; CurDAG->dump());
688 CurDAG->NewNodesMustHaveLegalTypes = true;
691 if (ViewDAGCombineLT)
692 CurDAG->viewGraph("dag-combine-lt input for " + BlockName);
694 // Run the DAG combiner in post-type-legalize mode.
696 NamedRegionTimer T("DAG Combining after legalize types", GroupName,
697 TimePassesIsEnabled);
698 CurDAG->Combine(AfterLegalizeTypes, *AA, OptLevel);
701 DEBUG(dbgs() << "Optimized type-legalized selection DAG: BB#" << BlockNumber
702 << " '" << BlockName << "'\n"; CurDAG->dump());
707 NamedRegionTimer T("Vector Legalization", GroupName, TimePassesIsEnabled);
708 Changed = CurDAG->LegalizeVectors();
713 NamedRegionTimer T("Type Legalization 2", GroupName, TimePassesIsEnabled);
714 CurDAG->LegalizeTypes();
717 if (ViewDAGCombineLT)
718 CurDAG->viewGraph("dag-combine-lv input for " + BlockName);
720 // Run the DAG combiner in post-type-legalize mode.
722 NamedRegionTimer T("DAG Combining after legalize vectors", GroupName,
723 TimePassesIsEnabled);
724 CurDAG->Combine(AfterLegalizeVectorOps, *AA, OptLevel);
727 DEBUG(dbgs() << "Optimized vector-legalized selection DAG: BB#"
728 << BlockNumber << " '" << BlockName << "'\n"; CurDAG->dump());
731 if (ViewLegalizeDAGs) CurDAG->viewGraph("legalize input for " + BlockName);
734 NamedRegionTimer T("DAG Legalization", GroupName, TimePassesIsEnabled);
738 DEBUG(dbgs() << "Legalized selection DAG: BB#" << BlockNumber
739 << " '" << BlockName << "'\n"; CurDAG->dump());
741 if (ViewDAGCombine2) CurDAG->viewGraph("dag-combine2 input for " + BlockName);
743 // Run the DAG combiner in post-legalize mode.
745 NamedRegionTimer T("DAG Combining 2", GroupName, TimePassesIsEnabled);
746 CurDAG->Combine(AfterLegalizeDAG, *AA, OptLevel);
749 DEBUG(dbgs() << "Optimized legalized selection DAG: BB#" << BlockNumber
750 << " '" << BlockName << "'\n"; CurDAG->dump());
752 if (OptLevel != CodeGenOpt::None)
753 ComputeLiveOutVRegInfo();
755 if (ViewISelDAGs) CurDAG->viewGraph("isel input for " + BlockName);
757 // Third, instruction select all of the operations to machine code, adding the
758 // code to the MachineBasicBlock.
760 NamedRegionTimer T("Instruction Selection", GroupName, TimePassesIsEnabled);
761 DoInstructionSelection();
764 DEBUG(dbgs() << "Selected selection DAG: BB#" << BlockNumber
765 << " '" << BlockName << "'\n"; CurDAG->dump());
767 if (ViewSchedDAGs) CurDAG->viewGraph("scheduler input for " + BlockName);
769 // Schedule machine code.
770 ScheduleDAGSDNodes *Scheduler = CreateScheduler();
772 NamedRegionTimer T("Instruction Scheduling", GroupName,
773 TimePassesIsEnabled);
774 Scheduler->Run(CurDAG, FuncInfo->MBB);
777 if (ViewSUnitDAGs) Scheduler->viewGraph();
779 // Emit machine code to BB. This can change 'BB' to the last block being
781 MachineBasicBlock *FirstMBB = FuncInfo->MBB, *LastMBB;
783 NamedRegionTimer T("Instruction Creation", GroupName, TimePassesIsEnabled);
785 // FuncInfo->InsertPt is passed by reference and set to the end of the
786 // scheduled instructions.
787 LastMBB = FuncInfo->MBB = Scheduler->EmitSchedule(FuncInfo->InsertPt);
790 // If the block was split, make sure we update any references that are used to
791 // update PHI nodes later on.
792 if (FirstMBB != LastMBB)
793 SDB->UpdateSplitBlock(FirstMBB, LastMBB);
795 // Free the scheduler state.
797 NamedRegionTimer T("Instruction Scheduling Cleanup", GroupName,
798 TimePassesIsEnabled);
802 // Free the SelectionDAG state, now that we're finished with it.
807 /// ISelUpdater - helper class to handle updates of the instruction selection
809 class ISelUpdater : public SelectionDAG::DAGUpdateListener {
810 SelectionDAG::allnodes_iterator &ISelPosition;
812 ISelUpdater(SelectionDAG &DAG, SelectionDAG::allnodes_iterator &isp)
813 : SelectionDAG::DAGUpdateListener(DAG), ISelPosition(isp) {}
815 /// NodeDeleted - Handle nodes deleted from the graph. If the node being
816 /// deleted is the current ISelPosition node, update ISelPosition.
818 void NodeDeleted(SDNode *N, SDNode *E) override {
819 if (ISelPosition == SelectionDAG::allnodes_iterator(N))
823 } // end anonymous namespace
825 void SelectionDAGISel::DoInstructionSelection() {
826 DEBUG(dbgs() << "===== Instruction selection begins: BB#"
827 << FuncInfo->MBB->getNumber()
828 << " '" << FuncInfo->MBB->getName() << "'\n");
832 // Select target instructions for the DAG.
834 // Number all nodes with a topological order and set DAGSize.
835 DAGSize = CurDAG->AssignTopologicalOrder();
837 // Create a dummy node (which is not added to allnodes), that adds
838 // a reference to the root node, preventing it from being deleted,
839 // and tracking any changes of the root.
840 HandleSDNode Dummy(CurDAG->getRoot());
841 SelectionDAG::allnodes_iterator ISelPosition (CurDAG->getRoot().getNode());
844 // Make sure that ISelPosition gets properly updated when nodes are deleted
845 // in calls made from this function.
846 ISelUpdater ISU(*CurDAG, ISelPosition);
848 // The AllNodes list is now topological-sorted. Visit the
849 // nodes by starting at the end of the list (the root of the
850 // graph) and preceding back toward the beginning (the entry
852 while (ISelPosition != CurDAG->allnodes_begin()) {
853 SDNode *Node = --ISelPosition;
854 // Skip dead nodes. DAGCombiner is expected to eliminate all dead nodes,
855 // but there are currently some corner cases that it misses. Also, this
856 // makes it theoretically possible to disable the DAGCombiner.
857 if (Node->use_empty())
860 SDNode *ResNode = Select(Node);
862 // FIXME: This is pretty gross. 'Select' should be changed to not return
863 // anything at all and this code should be nuked with a tactical strike.
865 // If node should not be replaced, continue with the next one.
866 if (ResNode == Node || Node->getOpcode() == ISD::DELETED_NODE)
870 ReplaceUses(Node, ResNode);
873 // If after the replacement this node is not used any more,
874 // remove this dead node.
875 if (Node->use_empty()) // Don't delete EntryToken, etc.
876 CurDAG->RemoveDeadNode(Node);
879 CurDAG->setRoot(Dummy.getValue());
882 DEBUG(dbgs() << "===== Instruction selection ends:\n");
884 PostprocessISelDAG();
887 /// PrepareEHLandingPad - Emit an EH_LABEL, set up live-in registers, and
888 /// do other setup for EH landing-pad blocks.
889 void SelectionDAGISel::PrepareEHLandingPad() {
890 MachineBasicBlock *MBB = FuncInfo->MBB;
892 // Add a label to mark the beginning of the landing pad. Deletion of the
893 // landing pad can thus be detected via the MachineModuleInfo.
894 MCSymbol *Label = MF->getMMI().addLandingPad(MBB);
896 // Assign the call site to the landing pad's begin label.
897 MF->getMMI().setCallSiteLandingPad(Label, SDB->LPadToCallSiteMap[MBB]);
899 const MCInstrDesc &II =
900 TM.getSubtargetImpl()->getInstrInfo()->get(TargetOpcode::EH_LABEL);
901 BuildMI(*MBB, FuncInfo->InsertPt, SDB->getCurDebugLoc(), II)
904 // Mark exception register as live in.
905 const TargetLowering *TLI = getTargetLowering();
906 const TargetRegisterClass *PtrRC = TLI->getRegClassFor(TLI->getPointerTy());
907 if (unsigned Reg = TLI->getExceptionPointerRegister())
908 FuncInfo->ExceptionPointerVirtReg = MBB->addLiveIn(Reg, PtrRC);
910 // Mark exception selector register as live in.
911 if (unsigned Reg = TLI->getExceptionSelectorRegister())
912 FuncInfo->ExceptionSelectorVirtReg = MBB->addLiveIn(Reg, PtrRC);
915 /// isFoldedOrDeadInstruction - Return true if the specified instruction is
916 /// side-effect free and is either dead or folded into a generated instruction.
917 /// Return false if it needs to be emitted.
918 static bool isFoldedOrDeadInstruction(const Instruction *I,
919 FunctionLoweringInfo *FuncInfo) {
920 return !I->mayWriteToMemory() && // Side-effecting instructions aren't folded.
921 !isa<TerminatorInst>(I) && // Terminators aren't folded.
922 !isa<DbgInfoIntrinsic>(I) && // Debug instructions aren't folded.
923 !isa<LandingPadInst>(I) && // Landingpad instructions aren't folded.
924 !FuncInfo->isExportedInst(I); // Exported instrs must be computed.
928 // Collect per Instruction statistics for fast-isel misses. Only those
929 // instructions that cause the bail are accounted for. It does not account for
930 // instructions higher in the block. Thus, summing the per instructions stats
931 // will not add up to what is reported by NumFastIselFailures.
932 static void collectFailStats(const Instruction *I) {
933 switch (I->getOpcode()) {
934 default: assert (0 && "<Invalid operator> ");
937 case Instruction::Ret: NumFastIselFailRet++; return;
938 case Instruction::Br: NumFastIselFailBr++; return;
939 case Instruction::Switch: NumFastIselFailSwitch++; return;
940 case Instruction::IndirectBr: NumFastIselFailIndirectBr++; return;
941 case Instruction::Invoke: NumFastIselFailInvoke++; return;
942 case Instruction::Resume: NumFastIselFailResume++; return;
943 case Instruction::Unreachable: NumFastIselFailUnreachable++; return;
945 // Standard binary operators...
946 case Instruction::Add: NumFastIselFailAdd++; return;
947 case Instruction::FAdd: NumFastIselFailFAdd++; return;
948 case Instruction::Sub: NumFastIselFailSub++; return;
949 case Instruction::FSub: NumFastIselFailFSub++; return;
950 case Instruction::Mul: NumFastIselFailMul++; return;
951 case Instruction::FMul: NumFastIselFailFMul++; return;
952 case Instruction::UDiv: NumFastIselFailUDiv++; return;
953 case Instruction::SDiv: NumFastIselFailSDiv++; return;
954 case Instruction::FDiv: NumFastIselFailFDiv++; return;
955 case Instruction::URem: NumFastIselFailURem++; return;
956 case Instruction::SRem: NumFastIselFailSRem++; return;
957 case Instruction::FRem: NumFastIselFailFRem++; return;
959 // Logical operators...
960 case Instruction::And: NumFastIselFailAnd++; return;
961 case Instruction::Or: NumFastIselFailOr++; return;
962 case Instruction::Xor: NumFastIselFailXor++; return;
964 // Memory instructions...
965 case Instruction::Alloca: NumFastIselFailAlloca++; return;
966 case Instruction::Load: NumFastIselFailLoad++; return;
967 case Instruction::Store: NumFastIselFailStore++; return;
968 case Instruction::AtomicCmpXchg: NumFastIselFailAtomicCmpXchg++; return;
969 case Instruction::AtomicRMW: NumFastIselFailAtomicRMW++; return;
970 case Instruction::Fence: NumFastIselFailFence++; return;
971 case Instruction::GetElementPtr: NumFastIselFailGetElementPtr++; return;
973 // Convert instructions...
974 case Instruction::Trunc: NumFastIselFailTrunc++; return;
975 case Instruction::ZExt: NumFastIselFailZExt++; return;
976 case Instruction::SExt: NumFastIselFailSExt++; return;
977 case Instruction::FPTrunc: NumFastIselFailFPTrunc++; return;
978 case Instruction::FPExt: NumFastIselFailFPExt++; return;
979 case Instruction::FPToUI: NumFastIselFailFPToUI++; return;
980 case Instruction::FPToSI: NumFastIselFailFPToSI++; return;
981 case Instruction::UIToFP: NumFastIselFailUIToFP++; return;
982 case Instruction::SIToFP: NumFastIselFailSIToFP++; return;
983 case Instruction::IntToPtr: NumFastIselFailIntToPtr++; return;
984 case Instruction::PtrToInt: NumFastIselFailPtrToInt++; return;
985 case Instruction::BitCast: NumFastIselFailBitCast++; return;
987 // Other instructions...
988 case Instruction::ICmp: NumFastIselFailICmp++; return;
989 case Instruction::FCmp: NumFastIselFailFCmp++; return;
990 case Instruction::PHI: NumFastIselFailPHI++; return;
991 case Instruction::Select: NumFastIselFailSelect++; return;
992 case Instruction::Call: {
993 if (auto const *Intrinsic = dyn_cast<IntrinsicInst>(I)) {
994 switch (Intrinsic->getIntrinsicID()) {
996 NumFastIselFailIntrinsicCall++; return;
997 case Intrinsic::sadd_with_overflow:
998 NumFastIselFailSAddWithOverflow++; return;
999 case Intrinsic::uadd_with_overflow:
1000 NumFastIselFailUAddWithOverflow++; return;
1001 case Intrinsic::ssub_with_overflow:
1002 NumFastIselFailSSubWithOverflow++; return;
1003 case Intrinsic::usub_with_overflow:
1004 NumFastIselFailUSubWithOverflow++; return;
1005 case Intrinsic::smul_with_overflow:
1006 NumFastIselFailSMulWithOverflow++; return;
1007 case Intrinsic::umul_with_overflow:
1008 NumFastIselFailUMulWithOverflow++; return;
1009 case Intrinsic::frameaddress:
1010 NumFastIselFailFrameaddress++; return;
1011 case Intrinsic::sqrt:
1012 NumFastIselFailSqrt++; return;
1013 case Intrinsic::experimental_stackmap:
1014 NumFastIselFailStackMap++; return;
1015 case Intrinsic::experimental_patchpoint_void: // fall-through
1016 case Intrinsic::experimental_patchpoint_i64:
1017 NumFastIselFailPatchPoint++; return;
1020 NumFastIselFailCall++;
1023 case Instruction::Shl: NumFastIselFailShl++; return;
1024 case Instruction::LShr: NumFastIselFailLShr++; return;
1025 case Instruction::AShr: NumFastIselFailAShr++; return;
1026 case Instruction::VAArg: NumFastIselFailVAArg++; return;
1027 case Instruction::ExtractElement: NumFastIselFailExtractElement++; return;
1028 case Instruction::InsertElement: NumFastIselFailInsertElement++; return;
1029 case Instruction::ShuffleVector: NumFastIselFailShuffleVector++; return;
1030 case Instruction::ExtractValue: NumFastIselFailExtractValue++; return;
1031 case Instruction::InsertValue: NumFastIselFailInsertValue++; return;
1032 case Instruction::LandingPad: NumFastIselFailLandingPad++; return;
1037 void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
1038 // Initialize the Fast-ISel state, if needed.
1039 FastISel *FastIS = nullptr;
1040 if (TM.Options.EnableFastISel)
1041 FastIS = getTargetLowering()->createFastISel(*FuncInfo, LibInfo);
1043 // Iterate over all basic blocks in the function.
1044 ReversePostOrderTraversal<const Function*> RPOT(&Fn);
1045 for (ReversePostOrderTraversal<const Function*>::rpo_iterator
1046 I = RPOT.begin(), E = RPOT.end(); I != E; ++I) {
1047 const BasicBlock *LLVMBB = *I;
1049 if (OptLevel != CodeGenOpt::None) {
1050 bool AllPredsVisited = true;
1051 for (const_pred_iterator PI = pred_begin(LLVMBB), PE = pred_end(LLVMBB);
1053 if (!FuncInfo->VisitedBBs.count(*PI)) {
1054 AllPredsVisited = false;
1059 if (AllPredsVisited) {
1060 for (BasicBlock::const_iterator I = LLVMBB->begin();
1061 const PHINode *PN = dyn_cast<PHINode>(I); ++I)
1062 FuncInfo->ComputePHILiveOutRegInfo(PN);
1064 for (BasicBlock::const_iterator I = LLVMBB->begin();
1065 const PHINode *PN = dyn_cast<PHINode>(I); ++I)
1066 FuncInfo->InvalidatePHILiveOutRegInfo(PN);
1069 FuncInfo->VisitedBBs.insert(LLVMBB);
1072 BasicBlock::const_iterator const Begin = LLVMBB->getFirstNonPHI();
1073 BasicBlock::const_iterator const End = LLVMBB->end();
1074 BasicBlock::const_iterator BI = End;
1076 FuncInfo->MBB = FuncInfo->MBBMap[LLVMBB];
1077 FuncInfo->InsertPt = FuncInfo->MBB->getFirstNonPHI();
1079 // Setup an EH landing-pad block.
1080 FuncInfo->ExceptionPointerVirtReg = 0;
1081 FuncInfo->ExceptionSelectorVirtReg = 0;
1082 if (FuncInfo->MBB->isLandingPad())
1083 PrepareEHLandingPad();
1085 // Before doing SelectionDAG ISel, see if FastISel has been requested.
1087 FastIS->startNewBlock();
1089 // Emit code for any incoming arguments. This must happen before
1090 // beginning FastISel on the entry block.
1091 if (LLVMBB == &Fn.getEntryBlock()) {
1094 // Lower any arguments needed in this block if this is the entry block.
1095 if (!FastIS->lowerArguments()) {
1096 // Fast isel failed to lower these arguments
1097 ++NumFastIselFailLowerArguments;
1098 if (EnableFastISelAbortArgs)
1099 llvm_unreachable("FastISel didn't lower all arguments");
1101 // Use SelectionDAG argument lowering
1103 CurDAG->setRoot(SDB->getControlRoot());
1105 CodeGenAndEmitDAG();
1108 // If we inserted any instructions at the beginning, make a note of
1109 // where they are, so we can be sure to emit subsequent instructions
1111 if (FuncInfo->InsertPt != FuncInfo->MBB->begin())
1112 FastIS->setLastLocalValue(std::prev(FuncInfo->InsertPt));
1114 FastIS->setLastLocalValue(nullptr);
1117 unsigned NumFastIselRemaining = std::distance(Begin, End);
1118 // Do FastISel on as many instructions as possible.
1119 for (; BI != Begin; --BI) {
1120 const Instruction *Inst = std::prev(BI);
1122 // If we no longer require this instruction, skip it.
1123 if (isFoldedOrDeadInstruction(Inst, FuncInfo)) {
1124 --NumFastIselRemaining;
1128 // Bottom-up: reset the insert pos at the top, after any local-value
1130 FastIS->recomputeInsertPt();
1132 // Try to select the instruction with FastISel.
1133 if (FastIS->selectInstruction(Inst)) {
1134 --NumFastIselRemaining;
1135 ++NumFastIselSuccess;
1136 // If fast isel succeeded, skip over all the folded instructions, and
1137 // then see if there is a load right before the selected instructions.
1138 // Try to fold the load if so.
1139 const Instruction *BeforeInst = Inst;
1140 while (BeforeInst != Begin) {
1141 BeforeInst = std::prev(BasicBlock::const_iterator(BeforeInst));
1142 if (!isFoldedOrDeadInstruction(BeforeInst, FuncInfo))
1145 if (BeforeInst != Inst && isa<LoadInst>(BeforeInst) &&
1146 BeforeInst->hasOneUse() &&
1147 FastIS->tryToFoldLoad(cast<LoadInst>(BeforeInst), Inst)) {
1148 // If we succeeded, don't re-select the load.
1149 BI = std::next(BasicBlock::const_iterator(BeforeInst));
1150 --NumFastIselRemaining;
1151 ++NumFastIselSuccess;
1157 if (EnableFastISelVerbose2)
1158 collectFailStats(Inst);
1161 // Then handle certain instructions as single-LLVM-Instruction blocks.
1162 if (isa<CallInst>(Inst)) {
1164 if (EnableFastISelVerbose || EnableFastISelAbort) {
1165 dbgs() << "FastISel missed call: ";
1169 if (!Inst->getType()->isVoidTy() && !Inst->use_empty()) {
1170 unsigned &R = FuncInfo->ValueMap[Inst];
1172 R = FuncInfo->CreateRegs(Inst->getType());
1175 bool HadTailCall = false;
1176 MachineBasicBlock::iterator SavedInsertPt = FuncInfo->InsertPt;
1177 SelectBasicBlock(Inst, BI, HadTailCall);
1179 // If the call was emitted as a tail call, we're done with the block.
1180 // We also need to delete any previously emitted instructions.
1182 FastIS->removeDeadCode(SavedInsertPt, FuncInfo->MBB->end());
1187 // Recompute NumFastIselRemaining as Selection DAG instruction
1188 // selection may have handled the call, input args, etc.
1189 unsigned RemainingNow = std::distance(Begin, BI);
1190 NumFastIselFailures += NumFastIselRemaining - RemainingNow;
1191 NumFastIselRemaining = RemainingNow;
1195 if (isa<TerminatorInst>(Inst) && !isa<BranchInst>(Inst)) {
1196 // Don't abort, and use a different message for terminator misses.
1197 NumFastIselFailures += NumFastIselRemaining;
1198 if (EnableFastISelVerbose || EnableFastISelAbort) {
1199 dbgs() << "FastISel missed terminator: ";
1203 NumFastIselFailures += NumFastIselRemaining;
1204 if (EnableFastISelVerbose || EnableFastISelAbort) {
1205 dbgs() << "FastISel miss: ";
1208 if (EnableFastISelAbort)
1209 // The "fast" selector couldn't handle something and bailed.
1210 // For the purpose of debugging, just abort.
1211 llvm_unreachable("FastISel didn't select the entire block");
1216 FastIS->recomputeInsertPt();
1218 // Lower any arguments needed in this block if this is the entry block.
1219 if (LLVMBB == &Fn.getEntryBlock()) {
1228 ++NumFastIselBlocks;
1231 // Run SelectionDAG instruction selection on the remainder of the block
1232 // not handled by FastISel. If FastISel is not run, this is the entire
1235 SelectBasicBlock(Begin, BI, HadTailCall);
1239 FuncInfo->PHINodesToUpdate.clear();
1243 SDB->clearDanglingDebugInfo();
1244 SDB->SPDescriptor.resetPerFunctionState();
1247 /// Given that the input MI is before a partial terminator sequence TSeq, return
1248 /// true if M + TSeq also a partial terminator sequence.
1250 /// A Terminator sequence is a sequence of MachineInstrs which at this point in
1251 /// lowering copy vregs into physical registers, which are then passed into
1252 /// terminator instructors so we can satisfy ABI constraints. A partial
1253 /// terminator sequence is an improper subset of a terminator sequence (i.e. it
1254 /// may be the whole terminator sequence).
1255 static bool MIIsInTerminatorSequence(const MachineInstr *MI) {
1256 // If we do not have a copy or an implicit def, we return true if and only if
1257 // MI is a debug value.
1258 if (!MI->isCopy() && !MI->isImplicitDef())
1259 // Sometimes DBG_VALUE MI sneak in between the copies from the vregs to the
1260 // physical registers if there is debug info associated with the terminator
1261 // of our mbb. We want to include said debug info in our terminator
1262 // sequence, so we return true in that case.
1263 return MI->isDebugValue();
1265 // We have left the terminator sequence if we are not doing one of the
1268 // 1. Copying a vreg into a physical register.
1269 // 2. Copying a vreg into a vreg.
1270 // 3. Defining a register via an implicit def.
1272 // OPI should always be a register definition...
1273 MachineInstr::const_mop_iterator OPI = MI->operands_begin();
1274 if (!OPI->isReg() || !OPI->isDef())
1277 // Defining any register via an implicit def is always ok.
1278 if (MI->isImplicitDef())
1281 // Grab the copy source...
1282 MachineInstr::const_mop_iterator OPI2 = OPI;
1284 assert(OPI2 != MI->operands_end()
1285 && "Should have a copy implying we should have 2 arguments.");
1287 // Make sure that the copy dest is not a vreg when the copy source is a
1288 // physical register.
1289 if (!OPI2->isReg() ||
1290 (!TargetRegisterInfo::isPhysicalRegister(OPI->getReg()) &&
1291 TargetRegisterInfo::isPhysicalRegister(OPI2->getReg())))
1297 /// Find the split point at which to splice the end of BB into its success stack
1298 /// protector check machine basic block.
1300 /// On many platforms, due to ABI constraints, terminators, even before register
1301 /// allocation, use physical registers. This creates an issue for us since
1302 /// physical registers at this point can not travel across basic
1303 /// blocks. Luckily, selectiondag always moves physical registers into vregs
1304 /// when they enter functions and moves them through a sequence of copies back
1305 /// into the physical registers right before the terminator creating a
1306 /// ``Terminator Sequence''. This function is searching for the beginning of the
1307 /// terminator sequence so that we can ensure that we splice off not just the
1308 /// terminator, but additionally the copies that move the vregs into the
1309 /// physical registers.
1310 static MachineBasicBlock::iterator
1311 FindSplitPointForStackProtector(MachineBasicBlock *BB, DebugLoc DL) {
1312 MachineBasicBlock::iterator SplitPoint = BB->getFirstTerminator();
1314 if (SplitPoint == BB->begin())
1317 MachineBasicBlock::iterator Start = BB->begin();
1318 MachineBasicBlock::iterator Previous = SplitPoint;
1321 while (MIIsInTerminatorSequence(Previous)) {
1322 SplitPoint = Previous;
1323 if (Previous == Start)
1332 SelectionDAGISel::FinishBasicBlock() {
1334 DEBUG(dbgs() << "Total amount of phi nodes to update: "
1335 << FuncInfo->PHINodesToUpdate.size() << "\n";
1336 for (unsigned i = 0, e = FuncInfo->PHINodesToUpdate.size(); i != e; ++i)
1337 dbgs() << "Node " << i << " : ("
1338 << FuncInfo->PHINodesToUpdate[i].first
1339 << ", " << FuncInfo->PHINodesToUpdate[i].second << ")\n");
1341 const bool MustUpdatePHINodes = SDB->SwitchCases.empty() &&
1342 SDB->JTCases.empty() &&
1343 SDB->BitTestCases.empty();
1345 // Next, now that we know what the last MBB the LLVM BB expanded is, update
1346 // PHI nodes in successors.
1347 if (MustUpdatePHINodes) {
1348 for (unsigned i = 0, e = FuncInfo->PHINodesToUpdate.size(); i != e; ++i) {
1349 MachineInstrBuilder PHI(*MF, FuncInfo->PHINodesToUpdate[i].first);
1350 assert(PHI->isPHI() &&
1351 "This is not a machine PHI node that we are updating!");
1352 if (!FuncInfo->MBB->isSuccessor(PHI->getParent()))
1354 PHI.addReg(FuncInfo->PHINodesToUpdate[i].second).addMBB(FuncInfo->MBB);
1358 // Handle stack protector.
1359 if (SDB->SPDescriptor.shouldEmitStackProtector()) {
1360 MachineBasicBlock *ParentMBB = SDB->SPDescriptor.getParentMBB();
1361 MachineBasicBlock *SuccessMBB = SDB->SPDescriptor.getSuccessMBB();
1363 // Find the split point to split the parent mbb. At the same time copy all
1364 // physical registers used in the tail of parent mbb into virtual registers
1365 // before the split point and back into physical registers after the split
1366 // point. This prevents us needing to deal with Live-ins and many other
1367 // register allocation issues caused by us splitting the parent mbb. The
1368 // register allocator will clean up said virtual copies later on.
1369 MachineBasicBlock::iterator SplitPoint =
1370 FindSplitPointForStackProtector(ParentMBB, SDB->getCurDebugLoc());
1372 // Splice the terminator of ParentMBB into SuccessMBB.
1373 SuccessMBB->splice(SuccessMBB->end(), ParentMBB,
1377 // Add compare/jump on neq/jump to the parent BB.
1378 FuncInfo->MBB = ParentMBB;
1379 FuncInfo->InsertPt = ParentMBB->end();
1380 SDB->visitSPDescriptorParent(SDB->SPDescriptor, ParentMBB);
1381 CurDAG->setRoot(SDB->getRoot());
1383 CodeGenAndEmitDAG();
1385 // CodeGen Failure MBB if we have not codegened it yet.
1386 MachineBasicBlock *FailureMBB = SDB->SPDescriptor.getFailureMBB();
1387 if (!FailureMBB->size()) {
1388 FuncInfo->MBB = FailureMBB;
1389 FuncInfo->InsertPt = FailureMBB->end();
1390 SDB->visitSPDescriptorFailure(SDB->SPDescriptor);
1391 CurDAG->setRoot(SDB->getRoot());
1393 CodeGenAndEmitDAG();
1396 // Clear the Per-BB State.
1397 SDB->SPDescriptor.resetPerBBState();
1400 // If we updated PHI Nodes, return early.
1401 if (MustUpdatePHINodes)
1404 for (unsigned i = 0, e = SDB->BitTestCases.size(); i != e; ++i) {
1405 // Lower header first, if it wasn't already lowered
1406 if (!SDB->BitTestCases[i].Emitted) {
1407 // Set the current basic block to the mbb we wish to insert the code into
1408 FuncInfo->MBB = SDB->BitTestCases[i].Parent;
1409 FuncInfo->InsertPt = FuncInfo->MBB->end();
1411 SDB->visitBitTestHeader(SDB->BitTestCases[i], FuncInfo->MBB);
1412 CurDAG->setRoot(SDB->getRoot());
1414 CodeGenAndEmitDAG();
1417 uint32_t UnhandledWeight = 0;
1418 for (unsigned j = 0, ej = SDB->BitTestCases[i].Cases.size(); j != ej; ++j)
1419 UnhandledWeight += SDB->BitTestCases[i].Cases[j].ExtraWeight;
1421 for (unsigned j = 0, ej = SDB->BitTestCases[i].Cases.size(); j != ej; ++j) {
1422 UnhandledWeight -= SDB->BitTestCases[i].Cases[j].ExtraWeight;
1423 // Set the current basic block to the mbb we wish to insert the code into
1424 FuncInfo->MBB = SDB->BitTestCases[i].Cases[j].ThisBB;
1425 FuncInfo->InsertPt = FuncInfo->MBB->end();
1428 SDB->visitBitTestCase(SDB->BitTestCases[i],
1429 SDB->BitTestCases[i].Cases[j+1].ThisBB,
1431 SDB->BitTestCases[i].Reg,
1432 SDB->BitTestCases[i].Cases[j],
1435 SDB->visitBitTestCase(SDB->BitTestCases[i],
1436 SDB->BitTestCases[i].Default,
1438 SDB->BitTestCases[i].Reg,
1439 SDB->BitTestCases[i].Cases[j],
1443 CurDAG->setRoot(SDB->getRoot());
1445 CodeGenAndEmitDAG();
1449 for (unsigned pi = 0, pe = FuncInfo->PHINodesToUpdate.size();
1451 MachineInstrBuilder PHI(*MF, FuncInfo->PHINodesToUpdate[pi].first);
1452 MachineBasicBlock *PHIBB = PHI->getParent();
1453 assert(PHI->isPHI() &&
1454 "This is not a machine PHI node that we are updating!");
1455 // This is "default" BB. We have two jumps to it. From "header" BB and
1456 // from last "case" BB.
1457 if (PHIBB == SDB->BitTestCases[i].Default)
1458 PHI.addReg(FuncInfo->PHINodesToUpdate[pi].second)
1459 .addMBB(SDB->BitTestCases[i].Parent)
1460 .addReg(FuncInfo->PHINodesToUpdate[pi].second)
1461 .addMBB(SDB->BitTestCases[i].Cases.back().ThisBB);
1462 // One of "cases" BB.
1463 for (unsigned j = 0, ej = SDB->BitTestCases[i].Cases.size();
1465 MachineBasicBlock* cBB = SDB->BitTestCases[i].Cases[j].ThisBB;
1466 if (cBB->isSuccessor(PHIBB))
1467 PHI.addReg(FuncInfo->PHINodesToUpdate[pi].second).addMBB(cBB);
1471 SDB->BitTestCases.clear();
1473 // If the JumpTable record is filled in, then we need to emit a jump table.
1474 // Updating the PHI nodes is tricky in this case, since we need to determine
1475 // whether the PHI is a successor of the range check MBB or the jump table MBB
1476 for (unsigned i = 0, e = SDB->JTCases.size(); i != e; ++i) {
1477 // Lower header first, if it wasn't already lowered
1478 if (!SDB->JTCases[i].first.Emitted) {
1479 // Set the current basic block to the mbb we wish to insert the code into
1480 FuncInfo->MBB = SDB->JTCases[i].first.HeaderBB;
1481 FuncInfo->InsertPt = FuncInfo->MBB->end();
1483 SDB->visitJumpTableHeader(SDB->JTCases[i].second, SDB->JTCases[i].first,
1485 CurDAG->setRoot(SDB->getRoot());
1487 CodeGenAndEmitDAG();
1490 // Set the current basic block to the mbb we wish to insert the code into
1491 FuncInfo->MBB = SDB->JTCases[i].second.MBB;
1492 FuncInfo->InsertPt = FuncInfo->MBB->end();
1494 SDB->visitJumpTable(SDB->JTCases[i].second);
1495 CurDAG->setRoot(SDB->getRoot());
1497 CodeGenAndEmitDAG();
1500 for (unsigned pi = 0, pe = FuncInfo->PHINodesToUpdate.size();
1502 MachineInstrBuilder PHI(*MF, FuncInfo->PHINodesToUpdate[pi].first);
1503 MachineBasicBlock *PHIBB = PHI->getParent();
1504 assert(PHI->isPHI() &&
1505 "This is not a machine PHI node that we are updating!");
1506 // "default" BB. We can go there only from header BB.
1507 if (PHIBB == SDB->JTCases[i].second.Default)
1508 PHI.addReg(FuncInfo->PHINodesToUpdate[pi].second)
1509 .addMBB(SDB->JTCases[i].first.HeaderBB);
1510 // JT BB. Just iterate over successors here
1511 if (FuncInfo->MBB->isSuccessor(PHIBB))
1512 PHI.addReg(FuncInfo->PHINodesToUpdate[pi].second).addMBB(FuncInfo->MBB);
1515 SDB->JTCases.clear();
1517 // If the switch block involved a branch to one of the actual successors, we
1518 // need to update PHI nodes in that block.
1519 for (unsigned i = 0, e = FuncInfo->PHINodesToUpdate.size(); i != e; ++i) {
1520 MachineInstrBuilder PHI(*MF, FuncInfo->PHINodesToUpdate[i].first);
1521 assert(PHI->isPHI() &&
1522 "This is not a machine PHI node that we are updating!");
1523 if (FuncInfo->MBB->isSuccessor(PHI->getParent()))
1524 PHI.addReg(FuncInfo->PHINodesToUpdate[i].second).addMBB(FuncInfo->MBB);
1527 // If we generated any switch lowering information, build and codegen any
1528 // additional DAGs necessary.
1529 for (unsigned i = 0, e = SDB->SwitchCases.size(); i != e; ++i) {
1530 // Set the current basic block to the mbb we wish to insert the code into
1531 FuncInfo->MBB = SDB->SwitchCases[i].ThisBB;
1532 FuncInfo->InsertPt = FuncInfo->MBB->end();
1534 // Determine the unique successors.
1535 SmallVector<MachineBasicBlock *, 2> Succs;
1536 Succs.push_back(SDB->SwitchCases[i].TrueBB);
1537 if (SDB->SwitchCases[i].TrueBB != SDB->SwitchCases[i].FalseBB)
1538 Succs.push_back(SDB->SwitchCases[i].FalseBB);
1540 // Emit the code. Note that this could result in FuncInfo->MBB being split.
1541 SDB->visitSwitchCase(SDB->SwitchCases[i], FuncInfo->MBB);
1542 CurDAG->setRoot(SDB->getRoot());
1544 CodeGenAndEmitDAG();
1546 // Remember the last block, now that any splitting is done, for use in
1547 // populating PHI nodes in successors.
1548 MachineBasicBlock *ThisBB = FuncInfo->MBB;
1550 // Handle any PHI nodes in successors of this chunk, as if we were coming
1551 // from the original BB before switch expansion. Note that PHI nodes can
1552 // occur multiple times in PHINodesToUpdate. We have to be very careful to
1553 // handle them the right number of times.
1554 for (unsigned i = 0, e = Succs.size(); i != e; ++i) {
1555 FuncInfo->MBB = Succs[i];
1556 FuncInfo->InsertPt = FuncInfo->MBB->end();
1557 // FuncInfo->MBB may have been removed from the CFG if a branch was
1559 if (ThisBB->isSuccessor(FuncInfo->MBB)) {
1560 for (MachineBasicBlock::iterator
1561 MBBI = FuncInfo->MBB->begin(), MBBE = FuncInfo->MBB->end();
1562 MBBI != MBBE && MBBI->isPHI(); ++MBBI) {
1563 MachineInstrBuilder PHI(*MF, MBBI);
1564 // This value for this PHI node is recorded in PHINodesToUpdate.
1565 for (unsigned pn = 0; ; ++pn) {
1566 assert(pn != FuncInfo->PHINodesToUpdate.size() &&
1567 "Didn't find PHI entry!");
1568 if (FuncInfo->PHINodesToUpdate[pn].first == PHI) {
1569 PHI.addReg(FuncInfo->PHINodesToUpdate[pn].second).addMBB(ThisBB);
1577 SDB->SwitchCases.clear();
1581 /// Create the scheduler. If a specific scheduler was specified
1582 /// via the SchedulerRegistry, use it, otherwise select the
1583 /// one preferred by the target.
1585 ScheduleDAGSDNodes *SelectionDAGISel::CreateScheduler() {
1586 RegisterScheduler::FunctionPassCtor Ctor = RegisterScheduler::getDefault();
1590 RegisterScheduler::setDefault(Ctor);
1593 return Ctor(this, OptLevel);
1596 //===----------------------------------------------------------------------===//
1597 // Helper functions used by the generated instruction selector.
1598 //===----------------------------------------------------------------------===//
1599 // Calls to these methods are generated by tblgen.
1601 /// CheckAndMask - The isel is trying to match something like (and X, 255). If
1602 /// the dag combiner simplified the 255, we still want to match. RHS is the
1603 /// actual value in the DAG on the RHS of an AND, and DesiredMaskS is the value
1604 /// specified in the .td file (e.g. 255).
1605 bool SelectionDAGISel::CheckAndMask(SDValue LHS, ConstantSDNode *RHS,
1606 int64_t DesiredMaskS) const {
1607 const APInt &ActualMask = RHS->getAPIntValue();
1608 const APInt &DesiredMask = APInt(LHS.getValueSizeInBits(), DesiredMaskS);
1610 // If the actual mask exactly matches, success!
1611 if (ActualMask == DesiredMask)
1614 // If the actual AND mask is allowing unallowed bits, this doesn't match.
1615 if (ActualMask.intersects(~DesiredMask))
1618 // Otherwise, the DAG Combiner may have proven that the value coming in is
1619 // either already zero or is not demanded. Check for known zero input bits.
1620 APInt NeededMask = DesiredMask & ~ActualMask;
1621 if (CurDAG->MaskedValueIsZero(LHS, NeededMask))
1624 // TODO: check to see if missing bits are just not demanded.
1626 // Otherwise, this pattern doesn't match.
1630 /// CheckOrMask - The isel is trying to match something like (or X, 255). If
1631 /// the dag combiner simplified the 255, we still want to match. RHS is the
1632 /// actual value in the DAG on the RHS of an OR, and DesiredMaskS is the value
1633 /// specified in the .td file (e.g. 255).
1634 bool SelectionDAGISel::CheckOrMask(SDValue LHS, ConstantSDNode *RHS,
1635 int64_t DesiredMaskS) const {
1636 const APInt &ActualMask = RHS->getAPIntValue();
1637 const APInt &DesiredMask = APInt(LHS.getValueSizeInBits(), DesiredMaskS);
1639 // If the actual mask exactly matches, success!
1640 if (ActualMask == DesiredMask)
1643 // If the actual AND mask is allowing unallowed bits, this doesn't match.
1644 if (ActualMask.intersects(~DesiredMask))
1647 // Otherwise, the DAG Combiner may have proven that the value coming in is
1648 // either already zero or is not demanded. Check for known zero input bits.
1649 APInt NeededMask = DesiredMask & ~ActualMask;
1651 APInt KnownZero, KnownOne;
1652 CurDAG->computeKnownBits(LHS, KnownZero, KnownOne);
1654 // If all the missing bits in the or are already known to be set, match!
1655 if ((NeededMask & KnownOne) == NeededMask)
1658 // TODO: check to see if missing bits are just not demanded.
1660 // Otherwise, this pattern doesn't match.
1665 /// SelectInlineAsmMemoryOperands - Calls to this are automatically generated
1666 /// by tblgen. Others should not call it.
1667 void SelectionDAGISel::
1668 SelectInlineAsmMemoryOperands(std::vector<SDValue> &Ops) {
1669 std::vector<SDValue> InOps;
1670 std::swap(InOps, Ops);
1672 Ops.push_back(InOps[InlineAsm::Op_InputChain]); // 0
1673 Ops.push_back(InOps[InlineAsm::Op_AsmString]); // 1
1674 Ops.push_back(InOps[InlineAsm::Op_MDNode]); // 2, !srcloc
1675 Ops.push_back(InOps[InlineAsm::Op_ExtraInfo]); // 3 (SideEffect, AlignStack)
1677 unsigned i = InlineAsm::Op_FirstOperand, e = InOps.size();
1678 if (InOps[e-1].getValueType() == MVT::Glue)
1679 --e; // Don't process a glue operand if it is here.
1682 unsigned Flags = cast<ConstantSDNode>(InOps[i])->getZExtValue();
1683 if (!InlineAsm::isMemKind(Flags)) {
1684 // Just skip over this operand, copying the operands verbatim.
1685 Ops.insert(Ops.end(), InOps.begin()+i,
1686 InOps.begin()+i+InlineAsm::getNumOperandRegisters(Flags) + 1);
1687 i += InlineAsm::getNumOperandRegisters(Flags) + 1;
1689 assert(InlineAsm::getNumOperandRegisters(Flags) == 1 &&
1690 "Memory operand with multiple values?");
1691 // Otherwise, this is a memory operand. Ask the target to select it.
1692 std::vector<SDValue> SelOps;
1693 if (SelectInlineAsmMemoryOperand(InOps[i+1], 'm', SelOps))
1694 report_fatal_error("Could not match memory address. Inline asm"
1697 // Add this to the output node.
1699 InlineAsm::getFlagWord(InlineAsm::Kind_Mem, SelOps.size());
1700 Ops.push_back(CurDAG->getTargetConstant(NewFlags, MVT::i32));
1701 Ops.insert(Ops.end(), SelOps.begin(), SelOps.end());
1706 // Add the glue input back if present.
1707 if (e != InOps.size())
1708 Ops.push_back(InOps.back());
1711 /// findGlueUse - Return use of MVT::Glue value produced by the specified
1714 static SDNode *findGlueUse(SDNode *N) {
1715 unsigned FlagResNo = N->getNumValues()-1;
1716 for (SDNode::use_iterator I = N->use_begin(), E = N->use_end(); I != E; ++I) {
1717 SDUse &Use = I.getUse();
1718 if (Use.getResNo() == FlagResNo)
1719 return Use.getUser();
1724 /// findNonImmUse - Return true if "Use" is a non-immediate use of "Def".
1725 /// This function recursively traverses up the operand chain, ignoring
1727 static bool findNonImmUse(SDNode *Use, SDNode* Def, SDNode *ImmedUse,
1728 SDNode *Root, SmallPtrSetImpl<SDNode*> &Visited,
1729 bool IgnoreChains) {
1730 // The NodeID's are given uniques ID's where a node ID is guaranteed to be
1731 // greater than all of its (recursive) operands. If we scan to a point where
1732 // 'use' is smaller than the node we're scanning for, then we know we will
1735 // The Use may be -1 (unassigned) if it is a newly allocated node. This can
1736 // happen because we scan down to newly selected nodes in the case of glue
1738 if ((Use->getNodeId() < Def->getNodeId() && Use->getNodeId() != -1))
1741 // Don't revisit nodes if we already scanned it and didn't fail, we know we
1742 // won't fail if we scan it again.
1743 if (!Visited.insert(Use))
1746 for (unsigned i = 0, e = Use->getNumOperands(); i != e; ++i) {
1747 // Ignore chain uses, they are validated by HandleMergeInputChains.
1748 if (Use->getOperand(i).getValueType() == MVT::Other && IgnoreChains)
1751 SDNode *N = Use->getOperand(i).getNode();
1753 if (Use == ImmedUse || Use == Root)
1754 continue; // We are not looking for immediate use.
1759 // Traverse up the operand chain.
1760 if (findNonImmUse(N, Def, ImmedUse, Root, Visited, IgnoreChains))
1766 /// IsProfitableToFold - Returns true if it's profitable to fold the specific
1767 /// operand node N of U during instruction selection that starts at Root.
1768 bool SelectionDAGISel::IsProfitableToFold(SDValue N, SDNode *U,
1769 SDNode *Root) const {
1770 if (OptLevel == CodeGenOpt::None) return false;
1771 return N.hasOneUse();
1774 /// IsLegalToFold - Returns true if the specific operand node N of
1775 /// U can be folded during instruction selection that starts at Root.
1776 bool SelectionDAGISel::IsLegalToFold(SDValue N, SDNode *U, SDNode *Root,
1777 CodeGenOpt::Level OptLevel,
1778 bool IgnoreChains) {
1779 if (OptLevel == CodeGenOpt::None) return false;
1781 // If Root use can somehow reach N through a path that that doesn't contain
1782 // U then folding N would create a cycle. e.g. In the following
1783 // diagram, Root can reach N through X. If N is folded into into Root, then
1784 // X is both a predecessor and a successor of U.
1795 // * indicates nodes to be folded together.
1797 // If Root produces glue, then it gets (even more) interesting. Since it
1798 // will be "glued" together with its glue use in the scheduler, we need to
1799 // check if it might reach N.
1818 // If GU (glue use) indirectly reaches N (the load), and Root folds N
1819 // (call it Fold), then X is a predecessor of GU and a successor of
1820 // Fold. But since Fold and GU are glued together, this will create
1821 // a cycle in the scheduling graph.
1823 // If the node has glue, walk down the graph to the "lowest" node in the
1825 EVT VT = Root->getValueType(Root->getNumValues()-1);
1826 while (VT == MVT::Glue) {
1827 SDNode *GU = findGlueUse(Root);
1831 VT = Root->getValueType(Root->getNumValues()-1);
1833 // If our query node has a glue result with a use, we've walked up it. If
1834 // the user (which has already been selected) has a chain or indirectly uses
1835 // the chain, our WalkChainUsers predicate will not consider it. Because of
1836 // this, we cannot ignore chains in this predicate.
1837 IgnoreChains = false;
1841 SmallPtrSet<SDNode*, 16> Visited;
1842 return !findNonImmUse(Root, N.getNode(), U, Root, Visited, IgnoreChains);
1845 SDNode *SelectionDAGISel::Select_INLINEASM(SDNode *N) {
1846 std::vector<SDValue> Ops(N->op_begin(), N->op_end());
1847 SelectInlineAsmMemoryOperands(Ops);
1849 EVT VTs[] = { MVT::Other, MVT::Glue };
1850 SDValue New = CurDAG->getNode(ISD::INLINEASM, SDLoc(N), VTs, Ops);
1852 return New.getNode();
1856 *SelectionDAGISel::Select_READ_REGISTER(SDNode *Op) {
1858 MDNodeSDNode *MD = dyn_cast<MDNodeSDNode>(Op->getOperand(0));
1859 const MDString *RegStr = dyn_cast<MDString>(MD->getMD()->getOperand(0));
1860 unsigned Reg = getTargetLowering()->getRegisterByName(
1861 RegStr->getString().data(), Op->getValueType(0));
1862 SDValue New = CurDAG->getCopyFromReg(
1863 CurDAG->getEntryNode(), dl, Reg, Op->getValueType(0));
1865 return New.getNode();
1869 *SelectionDAGISel::Select_WRITE_REGISTER(SDNode *Op) {
1871 MDNodeSDNode *MD = dyn_cast<MDNodeSDNode>(Op->getOperand(1));
1872 const MDString *RegStr = dyn_cast<MDString>(MD->getMD()->getOperand(0));
1873 unsigned Reg = getTargetLowering()->getRegisterByName(
1874 RegStr->getString().data(), Op->getOperand(2).getValueType());
1875 SDValue New = CurDAG->getCopyToReg(
1876 CurDAG->getEntryNode(), dl, Reg, Op->getOperand(2));
1878 return New.getNode();
1883 SDNode *SelectionDAGISel::Select_UNDEF(SDNode *N) {
1884 return CurDAG->SelectNodeTo(N, TargetOpcode::IMPLICIT_DEF,N->getValueType(0));
1887 /// GetVBR - decode a vbr encoding whose top bit is set.
1888 LLVM_ATTRIBUTE_ALWAYS_INLINE static uint64_t
1889 GetVBR(uint64_t Val, const unsigned char *MatcherTable, unsigned &Idx) {
1890 assert(Val >= 128 && "Not a VBR");
1891 Val &= 127; // Remove first vbr bit.
1896 NextBits = MatcherTable[Idx++];
1897 Val |= (NextBits&127) << Shift;
1899 } while (NextBits & 128);
1905 /// UpdateChainsAndGlue - When a match is complete, this method updates uses of
1906 /// interior glue and chain results to use the new glue and chain results.
1907 void SelectionDAGISel::
1908 UpdateChainsAndGlue(SDNode *NodeToMatch, SDValue InputChain,
1909 const SmallVectorImpl<SDNode*> &ChainNodesMatched,
1911 const SmallVectorImpl<SDNode*> &GlueResultNodesMatched,
1912 bool isMorphNodeTo) {
1913 SmallVector<SDNode*, 4> NowDeadNodes;
1915 // Now that all the normal results are replaced, we replace the chain and
1916 // glue results if present.
1917 if (!ChainNodesMatched.empty()) {
1918 assert(InputChain.getNode() &&
1919 "Matched input chains but didn't produce a chain");
1920 // Loop over all of the nodes we matched that produced a chain result.
1921 // Replace all the chain results with the final chain we ended up with.
1922 for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) {
1923 SDNode *ChainNode = ChainNodesMatched[i];
1925 // If this node was already deleted, don't look at it.
1926 if (ChainNode->getOpcode() == ISD::DELETED_NODE)
1929 // Don't replace the results of the root node if we're doing a
1931 if (ChainNode == NodeToMatch && isMorphNodeTo)
1934 SDValue ChainVal = SDValue(ChainNode, ChainNode->getNumValues()-1);
1935 if (ChainVal.getValueType() == MVT::Glue)
1936 ChainVal = ChainVal.getValue(ChainVal->getNumValues()-2);
1937 assert(ChainVal.getValueType() == MVT::Other && "Not a chain?");
1938 CurDAG->ReplaceAllUsesOfValueWith(ChainVal, InputChain);
1940 // If the node became dead and we haven't already seen it, delete it.
1941 if (ChainNode->use_empty() &&
1942 !std::count(NowDeadNodes.begin(), NowDeadNodes.end(), ChainNode))
1943 NowDeadNodes.push_back(ChainNode);
1947 // If the result produces glue, update any glue results in the matched
1948 // pattern with the glue result.
1949 if (InputGlue.getNode()) {
1950 // Handle any interior nodes explicitly marked.
1951 for (unsigned i = 0, e = GlueResultNodesMatched.size(); i != e; ++i) {
1952 SDNode *FRN = GlueResultNodesMatched[i];
1954 // If this node was already deleted, don't look at it.
1955 if (FRN->getOpcode() == ISD::DELETED_NODE)
1958 assert(FRN->getValueType(FRN->getNumValues()-1) == MVT::Glue &&
1959 "Doesn't have a glue result");
1960 CurDAG->ReplaceAllUsesOfValueWith(SDValue(FRN, FRN->getNumValues()-1),
1963 // If the node became dead and we haven't already seen it, delete it.
1964 if (FRN->use_empty() &&
1965 !std::count(NowDeadNodes.begin(), NowDeadNodes.end(), FRN))
1966 NowDeadNodes.push_back(FRN);
1970 if (!NowDeadNodes.empty())
1971 CurDAG->RemoveDeadNodes(NowDeadNodes);
1973 DEBUG(dbgs() << "ISEL: Match complete!\n");
1979 CR_LeadsToInteriorNode
1982 /// WalkChainUsers - Walk down the users of the specified chained node that is
1983 /// part of the pattern we're matching, looking at all of the users we find.
1984 /// This determines whether something is an interior node, whether we have a
1985 /// non-pattern node in between two pattern nodes (which prevent folding because
1986 /// it would induce a cycle) and whether we have a TokenFactor node sandwiched
1987 /// between pattern nodes (in which case the TF becomes part of the pattern).
1989 /// The walk we do here is guaranteed to be small because we quickly get down to
1990 /// already selected nodes "below" us.
1992 WalkChainUsers(const SDNode *ChainedNode,
1993 SmallVectorImpl<SDNode*> &ChainedNodesInPattern,
1994 SmallVectorImpl<SDNode*> &InteriorChainedNodes) {
1995 ChainResult Result = CR_Simple;
1997 for (SDNode::use_iterator UI = ChainedNode->use_begin(),
1998 E = ChainedNode->use_end(); UI != E; ++UI) {
1999 // Make sure the use is of the chain, not some other value we produce.
2000 if (UI.getUse().getValueType() != MVT::Other) continue;
2004 if (User->getOpcode() == ISD::HANDLENODE) // Root of the graph.
2007 // If we see an already-selected machine node, then we've gone beyond the
2008 // pattern that we're selecting down into the already selected chunk of the
2010 unsigned UserOpcode = User->getOpcode();
2011 if (User->isMachineOpcode() ||
2012 UserOpcode == ISD::CopyToReg ||
2013 UserOpcode == ISD::CopyFromReg ||
2014 UserOpcode == ISD::INLINEASM ||
2015 UserOpcode == ISD::EH_LABEL ||
2016 UserOpcode == ISD::LIFETIME_START ||
2017 UserOpcode == ISD::LIFETIME_END) {
2018 // If their node ID got reset to -1 then they've already been selected.
2019 // Treat them like a MachineOpcode.
2020 if (User->getNodeId() == -1)
2024 // If we have a TokenFactor, we handle it specially.
2025 if (User->getOpcode() != ISD::TokenFactor) {
2026 // If the node isn't a token factor and isn't part of our pattern, then it
2027 // must be a random chained node in between two nodes we're selecting.
2028 // This happens when we have something like:
2033 // Because we structurally match the load/store as a read/modify/write,
2034 // but the call is chained between them. We cannot fold in this case
2035 // because it would induce a cycle in the graph.
2036 if (!std::count(ChainedNodesInPattern.begin(),
2037 ChainedNodesInPattern.end(), User))
2038 return CR_InducesCycle;
2040 // Otherwise we found a node that is part of our pattern. For example in:
2044 // This would happen when we're scanning down from the load and see the
2045 // store as a user. Record that there is a use of ChainedNode that is
2046 // part of the pattern and keep scanning uses.
2047 Result = CR_LeadsToInteriorNode;
2048 InteriorChainedNodes.push_back(User);
2052 // If we found a TokenFactor, there are two cases to consider: first if the
2053 // TokenFactor is just hanging "below" the pattern we're matching (i.e. no
2054 // uses of the TF are in our pattern) we just want to ignore it. Second,
2055 // the TokenFactor can be sandwiched in between two chained nodes, like so:
2061 // | \ DAG's like cheese
2064 // [TokenFactor] [Op]
2071 // In this case, the TokenFactor becomes part of our match and we rewrite it
2072 // as a new TokenFactor.
2074 // To distinguish these two cases, do a recursive walk down the uses.
2075 switch (WalkChainUsers(User, ChainedNodesInPattern, InteriorChainedNodes)) {
2077 // If the uses of the TokenFactor are just already-selected nodes, ignore
2078 // it, it is "below" our pattern.
2080 case CR_InducesCycle:
2081 // If the uses of the TokenFactor lead to nodes that are not part of our
2082 // pattern that are not selected, folding would turn this into a cycle,
2084 return CR_InducesCycle;
2085 case CR_LeadsToInteriorNode:
2086 break; // Otherwise, keep processing.
2089 // Okay, we know we're in the interesting interior case. The TokenFactor
2090 // is now going to be considered part of the pattern so that we rewrite its
2091 // uses (it may have uses that are not part of the pattern) with the
2092 // ultimate chain result of the generated code. We will also add its chain
2093 // inputs as inputs to the ultimate TokenFactor we create.
2094 Result = CR_LeadsToInteriorNode;
2095 ChainedNodesInPattern.push_back(User);
2096 InteriorChainedNodes.push_back(User);
2103 /// HandleMergeInputChains - This implements the OPC_EmitMergeInputChains
2104 /// operation for when the pattern matched at least one node with a chains. The
2105 /// input vector contains a list of all of the chained nodes that we match. We
2106 /// must determine if this is a valid thing to cover (i.e. matching it won't
2107 /// induce cycles in the DAG) and if so, creating a TokenFactor node. that will
2108 /// be used as the input node chain for the generated nodes.
2110 HandleMergeInputChains(SmallVectorImpl<SDNode*> &ChainNodesMatched,
2111 SelectionDAG *CurDAG) {
2112 // Walk all of the chained nodes we've matched, recursively scanning down the
2113 // users of the chain result. This adds any TokenFactor nodes that are caught
2114 // in between chained nodes to the chained and interior nodes list.
2115 SmallVector<SDNode*, 3> InteriorChainedNodes;
2116 for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) {
2117 if (WalkChainUsers(ChainNodesMatched[i], ChainNodesMatched,
2118 InteriorChainedNodes) == CR_InducesCycle)
2119 return SDValue(); // Would induce a cycle.
2122 // Okay, we have walked all the matched nodes and collected TokenFactor nodes
2123 // that we are interested in. Form our input TokenFactor node.
2124 SmallVector<SDValue, 3> InputChains;
2125 for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) {
2126 // Add the input chain of this node to the InputChains list (which will be
2127 // the operands of the generated TokenFactor) if it's not an interior node.
2128 SDNode *N = ChainNodesMatched[i];
2129 if (N->getOpcode() != ISD::TokenFactor) {
2130 if (std::count(InteriorChainedNodes.begin(),InteriorChainedNodes.end(),N))
2133 // Otherwise, add the input chain.
2134 SDValue InChain = ChainNodesMatched[i]->getOperand(0);
2135 assert(InChain.getValueType() == MVT::Other && "Not a chain");
2136 InputChains.push_back(InChain);
2140 // If we have a token factor, we want to add all inputs of the token factor
2141 // that are not part of the pattern we're matching.
2142 for (unsigned op = 0, e = N->getNumOperands(); op != e; ++op) {
2143 if (!std::count(ChainNodesMatched.begin(), ChainNodesMatched.end(),
2144 N->getOperand(op).getNode()))
2145 InputChains.push_back(N->getOperand(op));
2149 if (InputChains.size() == 1)
2150 return InputChains[0];
2151 return CurDAG->getNode(ISD::TokenFactor, SDLoc(ChainNodesMatched[0]),
2152 MVT::Other, InputChains);
2155 /// MorphNode - Handle morphing a node in place for the selector.
2156 SDNode *SelectionDAGISel::
2157 MorphNode(SDNode *Node, unsigned TargetOpc, SDVTList VTList,
2158 ArrayRef<SDValue> Ops, unsigned EmitNodeInfo) {
2159 // It is possible we're using MorphNodeTo to replace a node with no
2160 // normal results with one that has a normal result (or we could be
2161 // adding a chain) and the input could have glue and chains as well.
2162 // In this case we need to shift the operands down.
2163 // FIXME: This is a horrible hack and broken in obscure cases, no worse
2164 // than the old isel though.
2165 int OldGlueResultNo = -1, OldChainResultNo = -1;
2167 unsigned NTMNumResults = Node->getNumValues();
2168 if (Node->getValueType(NTMNumResults-1) == MVT::Glue) {
2169 OldGlueResultNo = NTMNumResults-1;
2170 if (NTMNumResults != 1 &&
2171 Node->getValueType(NTMNumResults-2) == MVT::Other)
2172 OldChainResultNo = NTMNumResults-2;
2173 } else if (Node->getValueType(NTMNumResults-1) == MVT::Other)
2174 OldChainResultNo = NTMNumResults-1;
2176 // Call the underlying SelectionDAG routine to do the transmogrification. Note
2177 // that this deletes operands of the old node that become dead.
2178 SDNode *Res = CurDAG->MorphNodeTo(Node, ~TargetOpc, VTList, Ops);
2180 // MorphNodeTo can operate in two ways: if an existing node with the
2181 // specified operands exists, it can just return it. Otherwise, it
2182 // updates the node in place to have the requested operands.
2184 // If we updated the node in place, reset the node ID. To the isel,
2185 // this should be just like a newly allocated machine node.
2189 unsigned ResNumResults = Res->getNumValues();
2190 // Move the glue if needed.
2191 if ((EmitNodeInfo & OPFL_GlueOutput) && OldGlueResultNo != -1 &&
2192 (unsigned)OldGlueResultNo != ResNumResults-1)
2193 CurDAG->ReplaceAllUsesOfValueWith(SDValue(Node, OldGlueResultNo),
2194 SDValue(Res, ResNumResults-1));
2196 if ((EmitNodeInfo & OPFL_GlueOutput) != 0)
2199 // Move the chain reference if needed.
2200 if ((EmitNodeInfo & OPFL_Chain) && OldChainResultNo != -1 &&
2201 (unsigned)OldChainResultNo != ResNumResults-1)
2202 CurDAG->ReplaceAllUsesOfValueWith(SDValue(Node, OldChainResultNo),
2203 SDValue(Res, ResNumResults-1));
2205 // Otherwise, no replacement happened because the node already exists. Replace
2206 // Uses of the old node with the new one.
2208 CurDAG->ReplaceAllUsesWith(Node, Res);
2213 /// CheckSame - Implements OP_CheckSame.
2214 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2215 CheckSame(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2217 const SmallVectorImpl<std::pair<SDValue, SDNode*> > &RecordedNodes) {
2218 // Accept if it is exactly the same as a previously recorded node.
2219 unsigned RecNo = MatcherTable[MatcherIndex++];
2220 assert(RecNo < RecordedNodes.size() && "Invalid CheckSame");
2221 return N == RecordedNodes[RecNo].first;
2224 /// CheckChildSame - Implements OP_CheckChildXSame.
2225 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2226 CheckChildSame(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2228 const SmallVectorImpl<std::pair<SDValue, SDNode*> > &RecordedNodes,
2230 if (ChildNo >= N.getNumOperands())
2231 return false; // Match fails if out of range child #.
2232 return ::CheckSame(MatcherTable, MatcherIndex, N.getOperand(ChildNo),
2236 /// CheckPatternPredicate - Implements OP_CheckPatternPredicate.
2237 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2238 CheckPatternPredicate(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2239 const SelectionDAGISel &SDISel) {
2240 return SDISel.CheckPatternPredicate(MatcherTable[MatcherIndex++]);
2243 /// CheckNodePredicate - Implements OP_CheckNodePredicate.
2244 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2245 CheckNodePredicate(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2246 const SelectionDAGISel &SDISel, SDNode *N) {
2247 return SDISel.CheckNodePredicate(N, MatcherTable[MatcherIndex++]);
2250 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2251 CheckOpcode(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2253 uint16_t Opc = MatcherTable[MatcherIndex++];
2254 Opc |= (unsigned short)MatcherTable[MatcherIndex++] << 8;
2255 return N->getOpcode() == Opc;
2258 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2259 CheckType(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2260 SDValue N, const TargetLowering *TLI) {
2261 MVT::SimpleValueType VT = (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2262 if (N.getValueType() == VT) return true;
2264 // Handle the case when VT is iPTR.
2265 return VT == MVT::iPTR && N.getValueType() == TLI->getPointerTy();
2268 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2269 CheckChildType(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2270 SDValue N, const TargetLowering *TLI, unsigned ChildNo) {
2271 if (ChildNo >= N.getNumOperands())
2272 return false; // Match fails if out of range child #.
2273 return ::CheckType(MatcherTable, MatcherIndex, N.getOperand(ChildNo), TLI);
2276 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2277 CheckCondCode(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2279 return cast<CondCodeSDNode>(N)->get() ==
2280 (ISD::CondCode)MatcherTable[MatcherIndex++];
2283 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2284 CheckValueType(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2285 SDValue N, const TargetLowering *TLI) {
2286 MVT::SimpleValueType VT = (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2287 if (cast<VTSDNode>(N)->getVT() == VT)
2290 // Handle the case when VT is iPTR.
2291 return VT == MVT::iPTR && cast<VTSDNode>(N)->getVT() == TLI->getPointerTy();
2294 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2295 CheckInteger(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2297 int64_t Val = MatcherTable[MatcherIndex++];
2299 Val = GetVBR(Val, MatcherTable, MatcherIndex);
2301 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N);
2302 return C && C->getSExtValue() == Val;
2305 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2306 CheckChildInteger(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2307 SDValue N, unsigned ChildNo) {
2308 if (ChildNo >= N.getNumOperands())
2309 return false; // Match fails if out of range child #.
2310 return ::CheckInteger(MatcherTable, MatcherIndex, N.getOperand(ChildNo));
2313 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2314 CheckAndImm(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2315 SDValue N, const SelectionDAGISel &SDISel) {
2316 int64_t Val = MatcherTable[MatcherIndex++];
2318 Val = GetVBR(Val, MatcherTable, MatcherIndex);
2320 if (N->getOpcode() != ISD::AND) return false;
2322 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N->getOperand(1));
2323 return C && SDISel.CheckAndMask(N.getOperand(0), C, Val);
2326 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2327 CheckOrImm(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2328 SDValue N, const SelectionDAGISel &SDISel) {
2329 int64_t Val = MatcherTable[MatcherIndex++];
2331 Val = GetVBR(Val, MatcherTable, MatcherIndex);
2333 if (N->getOpcode() != ISD::OR) return false;
2335 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N->getOperand(1));
2336 return C && SDISel.CheckOrMask(N.getOperand(0), C, Val);
2339 /// IsPredicateKnownToFail - If we know how and can do so without pushing a
2340 /// scope, evaluate the current node. If the current predicate is known to
2341 /// fail, set Result=true and return anything. If the current predicate is
2342 /// known to pass, set Result=false and return the MatcherIndex to continue
2343 /// with. If the current predicate is unknown, set Result=false and return the
2344 /// MatcherIndex to continue with.
2345 static unsigned IsPredicateKnownToFail(const unsigned char *Table,
2346 unsigned Index, SDValue N,
2348 const SelectionDAGISel &SDISel,
2349 SmallVectorImpl<std::pair<SDValue, SDNode*> > &RecordedNodes) {
2350 switch (Table[Index++]) {
2353 return Index-1; // Could not evaluate this predicate.
2354 case SelectionDAGISel::OPC_CheckSame:
2355 Result = !::CheckSame(Table, Index, N, RecordedNodes);
2357 case SelectionDAGISel::OPC_CheckChild0Same:
2358 case SelectionDAGISel::OPC_CheckChild1Same:
2359 case SelectionDAGISel::OPC_CheckChild2Same:
2360 case SelectionDAGISel::OPC_CheckChild3Same:
2361 Result = !::CheckChildSame(Table, Index, N, RecordedNodes,
2362 Table[Index-1] - SelectionDAGISel::OPC_CheckChild0Same);
2364 case SelectionDAGISel::OPC_CheckPatternPredicate:
2365 Result = !::CheckPatternPredicate(Table, Index, SDISel);
2367 case SelectionDAGISel::OPC_CheckPredicate:
2368 Result = !::CheckNodePredicate(Table, Index, SDISel, N.getNode());
2370 case SelectionDAGISel::OPC_CheckOpcode:
2371 Result = !::CheckOpcode(Table, Index, N.getNode());
2373 case SelectionDAGISel::OPC_CheckType:
2374 Result = !::CheckType(Table, Index, N, SDISel.getTargetLowering());
2376 case SelectionDAGISel::OPC_CheckChild0Type:
2377 case SelectionDAGISel::OPC_CheckChild1Type:
2378 case SelectionDAGISel::OPC_CheckChild2Type:
2379 case SelectionDAGISel::OPC_CheckChild3Type:
2380 case SelectionDAGISel::OPC_CheckChild4Type:
2381 case SelectionDAGISel::OPC_CheckChild5Type:
2382 case SelectionDAGISel::OPC_CheckChild6Type:
2383 case SelectionDAGISel::OPC_CheckChild7Type:
2384 Result = !::CheckChildType(Table, Index, N, SDISel.getTargetLowering(),
2385 Table[Index-1] - SelectionDAGISel::OPC_CheckChild0Type);
2387 case SelectionDAGISel::OPC_CheckCondCode:
2388 Result = !::CheckCondCode(Table, Index, N);
2390 case SelectionDAGISel::OPC_CheckValueType:
2391 Result = !::CheckValueType(Table, Index, N, SDISel.getTargetLowering());
2393 case SelectionDAGISel::OPC_CheckInteger:
2394 Result = !::CheckInteger(Table, Index, N);
2396 case SelectionDAGISel::OPC_CheckChild0Integer:
2397 case SelectionDAGISel::OPC_CheckChild1Integer:
2398 case SelectionDAGISel::OPC_CheckChild2Integer:
2399 case SelectionDAGISel::OPC_CheckChild3Integer:
2400 case SelectionDAGISel::OPC_CheckChild4Integer:
2401 Result = !::CheckChildInteger(Table, Index, N,
2402 Table[Index-1] - SelectionDAGISel::OPC_CheckChild0Integer);
2404 case SelectionDAGISel::OPC_CheckAndImm:
2405 Result = !::CheckAndImm(Table, Index, N, SDISel);
2407 case SelectionDAGISel::OPC_CheckOrImm:
2408 Result = !::CheckOrImm(Table, Index, N, SDISel);
2416 /// FailIndex - If this match fails, this is the index to continue with.
2419 /// NodeStack - The node stack when the scope was formed.
2420 SmallVector<SDValue, 4> NodeStack;
2422 /// NumRecordedNodes - The number of recorded nodes when the scope was formed.
2423 unsigned NumRecordedNodes;
2425 /// NumMatchedMemRefs - The number of matched memref entries.
2426 unsigned NumMatchedMemRefs;
2428 /// InputChain/InputGlue - The current chain/glue
2429 SDValue InputChain, InputGlue;
2431 /// HasChainNodesMatched - True if the ChainNodesMatched list is non-empty.
2432 bool HasChainNodesMatched, HasGlueResultNodesMatched;
2435 /// \\brief A DAG update listener to keep the matching state
2436 /// (i.e. RecordedNodes and MatchScope) uptodate if the target is allowed to
2437 /// change the DAG while matching. X86 addressing mode matcher is an example
2439 class MatchStateUpdater : public SelectionDAG::DAGUpdateListener
2441 SmallVectorImpl<std::pair<SDValue, SDNode*> > &RecordedNodes;
2442 SmallVectorImpl<MatchScope> &MatchScopes;
2444 MatchStateUpdater(SelectionDAG &DAG,
2445 SmallVectorImpl<std::pair<SDValue, SDNode*> > &RN,
2446 SmallVectorImpl<MatchScope> &MS) :
2447 SelectionDAG::DAGUpdateListener(DAG),
2448 RecordedNodes(RN), MatchScopes(MS) { }
2450 void NodeDeleted(SDNode *N, SDNode *E) {
2451 // Some early-returns here to avoid the search if we deleted the node or
2452 // if the update comes from MorphNodeTo (MorphNodeTo is the last thing we
2453 // do, so it's unnecessary to update matching state at that point).
2454 // Neither of these can occur currently because we only install this
2455 // update listener during matching a complex patterns.
2456 if (!E || E->isMachineOpcode())
2458 // Performing linear search here does not matter because we almost never
2459 // run this code. You'd have to have a CSE during complex pattern
2461 for (auto &I : RecordedNodes)
2462 if (I.first.getNode() == N)
2465 for (auto &I : MatchScopes)
2466 for (auto &J : I.NodeStack)
2467 if (J.getNode() == N)
2473 SDNode *SelectionDAGISel::
2474 SelectCodeCommon(SDNode *NodeToMatch, const unsigned char *MatcherTable,
2475 unsigned TableSize) {
2476 // FIXME: Should these even be selected? Handle these cases in the caller?
2477 switch (NodeToMatch->getOpcode()) {
2480 case ISD::EntryToken: // These nodes remain the same.
2481 case ISD::BasicBlock:
2483 case ISD::RegisterMask:
2484 case ISD::HANDLENODE:
2485 case ISD::MDNODE_SDNODE:
2486 case ISD::TargetConstant:
2487 case ISD::TargetConstantFP:
2488 case ISD::TargetConstantPool:
2489 case ISD::TargetFrameIndex:
2490 case ISD::TargetExternalSymbol:
2491 case ISD::TargetBlockAddress:
2492 case ISD::TargetJumpTable:
2493 case ISD::TargetGlobalTLSAddress:
2494 case ISD::TargetGlobalAddress:
2495 case ISD::TokenFactor:
2496 case ISD::CopyFromReg:
2497 case ISD::CopyToReg:
2499 case ISD::LIFETIME_START:
2500 case ISD::LIFETIME_END:
2501 NodeToMatch->setNodeId(-1); // Mark selected.
2503 case ISD::AssertSext:
2504 case ISD::AssertZext:
2505 CurDAG->ReplaceAllUsesOfValueWith(SDValue(NodeToMatch, 0),
2506 NodeToMatch->getOperand(0));
2508 case ISD::INLINEASM: return Select_INLINEASM(NodeToMatch);
2509 case ISD::READ_REGISTER: return Select_READ_REGISTER(NodeToMatch);
2510 case ISD::WRITE_REGISTER: return Select_WRITE_REGISTER(NodeToMatch);
2511 case ISD::UNDEF: return Select_UNDEF(NodeToMatch);
2514 assert(!NodeToMatch->isMachineOpcode() && "Node already selected!");
2516 // Set up the node stack with NodeToMatch as the only node on the stack.
2517 SmallVector<SDValue, 8> NodeStack;
2518 SDValue N = SDValue(NodeToMatch, 0);
2519 NodeStack.push_back(N);
2521 // MatchScopes - Scopes used when matching, if a match failure happens, this
2522 // indicates where to continue checking.
2523 SmallVector<MatchScope, 8> MatchScopes;
2525 // RecordedNodes - This is the set of nodes that have been recorded by the
2526 // state machine. The second value is the parent of the node, or null if the
2527 // root is recorded.
2528 SmallVector<std::pair<SDValue, SDNode*>, 8> RecordedNodes;
2530 // MatchedMemRefs - This is the set of MemRef's we've seen in the input
2532 SmallVector<MachineMemOperand*, 2> MatchedMemRefs;
2534 // These are the current input chain and glue for use when generating nodes.
2535 // Various Emit operations change these. For example, emitting a copytoreg
2536 // uses and updates these.
2537 SDValue InputChain, InputGlue;
2539 // ChainNodesMatched - If a pattern matches nodes that have input/output
2540 // chains, the OPC_EmitMergeInputChains operation is emitted which indicates
2541 // which ones they are. The result is captured into this list so that we can
2542 // update the chain results when the pattern is complete.
2543 SmallVector<SDNode*, 3> ChainNodesMatched;
2544 SmallVector<SDNode*, 3> GlueResultNodesMatched;
2546 DEBUG(dbgs() << "ISEL: Starting pattern match on root node: ";
2547 NodeToMatch->dump(CurDAG);
2550 // Determine where to start the interpreter. Normally we start at opcode #0,
2551 // but if the state machine starts with an OPC_SwitchOpcode, then we
2552 // accelerate the first lookup (which is guaranteed to be hot) with the
2553 // OpcodeOffset table.
2554 unsigned MatcherIndex = 0;
2556 if (!OpcodeOffset.empty()) {
2557 // Already computed the OpcodeOffset table, just index into it.
2558 if (N.getOpcode() < OpcodeOffset.size())
2559 MatcherIndex = OpcodeOffset[N.getOpcode()];
2560 DEBUG(dbgs() << " Initial Opcode index to " << MatcherIndex << "\n");
2562 } else if (MatcherTable[0] == OPC_SwitchOpcode) {
2563 // Otherwise, the table isn't computed, but the state machine does start
2564 // with an OPC_SwitchOpcode instruction. Populate the table now, since this
2565 // is the first time we're selecting an instruction.
2568 // Get the size of this case.
2569 unsigned CaseSize = MatcherTable[Idx++];
2571 CaseSize = GetVBR(CaseSize, MatcherTable, Idx);
2572 if (CaseSize == 0) break;
2574 // Get the opcode, add the index to the table.
2575 uint16_t Opc = MatcherTable[Idx++];
2576 Opc |= (unsigned short)MatcherTable[Idx++] << 8;
2577 if (Opc >= OpcodeOffset.size())
2578 OpcodeOffset.resize((Opc+1)*2);
2579 OpcodeOffset[Opc] = Idx;
2583 // Okay, do the lookup for the first opcode.
2584 if (N.getOpcode() < OpcodeOffset.size())
2585 MatcherIndex = OpcodeOffset[N.getOpcode()];
2589 assert(MatcherIndex < TableSize && "Invalid index");
2591 unsigned CurrentOpcodeIndex = MatcherIndex;
2593 BuiltinOpcodes Opcode = (BuiltinOpcodes)MatcherTable[MatcherIndex++];
2596 // Okay, the semantics of this operation are that we should push a scope
2597 // then evaluate the first child. However, pushing a scope only to have
2598 // the first check fail (which then pops it) is inefficient. If we can
2599 // determine immediately that the first check (or first several) will
2600 // immediately fail, don't even bother pushing a scope for them.
2604 unsigned NumToSkip = MatcherTable[MatcherIndex++];
2605 if (NumToSkip & 128)
2606 NumToSkip = GetVBR(NumToSkip, MatcherTable, MatcherIndex);
2607 // Found the end of the scope with no match.
2608 if (NumToSkip == 0) {
2613 FailIndex = MatcherIndex+NumToSkip;
2615 unsigned MatcherIndexOfPredicate = MatcherIndex;
2616 (void)MatcherIndexOfPredicate; // silence warning.
2618 // If we can't evaluate this predicate without pushing a scope (e.g. if
2619 // it is a 'MoveParent') or if the predicate succeeds on this node, we
2620 // push the scope and evaluate the full predicate chain.
2622 MatcherIndex = IsPredicateKnownToFail(MatcherTable, MatcherIndex, N,
2623 Result, *this, RecordedNodes);
2627 DEBUG(dbgs() << " Skipped scope entry (due to false predicate) at "
2628 << "index " << MatcherIndexOfPredicate
2629 << ", continuing at " << FailIndex << "\n");
2630 ++NumDAGIselRetries;
2632 // Otherwise, we know that this case of the Scope is guaranteed to fail,
2633 // move to the next case.
2634 MatcherIndex = FailIndex;
2637 // If the whole scope failed to match, bail.
2638 if (FailIndex == 0) break;
2640 // Push a MatchScope which indicates where to go if the first child fails
2642 MatchScope NewEntry;
2643 NewEntry.FailIndex = FailIndex;
2644 NewEntry.NodeStack.append(NodeStack.begin(), NodeStack.end());
2645 NewEntry.NumRecordedNodes = RecordedNodes.size();
2646 NewEntry.NumMatchedMemRefs = MatchedMemRefs.size();
2647 NewEntry.InputChain = InputChain;
2648 NewEntry.InputGlue = InputGlue;
2649 NewEntry.HasChainNodesMatched = !ChainNodesMatched.empty();
2650 NewEntry.HasGlueResultNodesMatched = !GlueResultNodesMatched.empty();
2651 MatchScopes.push_back(NewEntry);
2654 case OPC_RecordNode: {
2655 // Remember this node, it may end up being an operand in the pattern.
2656 SDNode *Parent = nullptr;
2657 if (NodeStack.size() > 1)
2658 Parent = NodeStack[NodeStack.size()-2].getNode();
2659 RecordedNodes.push_back(std::make_pair(N, Parent));
2663 case OPC_RecordChild0: case OPC_RecordChild1:
2664 case OPC_RecordChild2: case OPC_RecordChild3:
2665 case OPC_RecordChild4: case OPC_RecordChild5:
2666 case OPC_RecordChild6: case OPC_RecordChild7: {
2667 unsigned ChildNo = Opcode-OPC_RecordChild0;
2668 if (ChildNo >= N.getNumOperands())
2669 break; // Match fails if out of range child #.
2671 RecordedNodes.push_back(std::make_pair(N->getOperand(ChildNo),
2675 case OPC_RecordMemRef:
2676 MatchedMemRefs.push_back(cast<MemSDNode>(N)->getMemOperand());
2679 case OPC_CaptureGlueInput:
2680 // If the current node has an input glue, capture it in InputGlue.
2681 if (N->getNumOperands() != 0 &&
2682 N->getOperand(N->getNumOperands()-1).getValueType() == MVT::Glue)
2683 InputGlue = N->getOperand(N->getNumOperands()-1);
2686 case OPC_MoveChild: {
2687 unsigned ChildNo = MatcherTable[MatcherIndex++];
2688 if (ChildNo >= N.getNumOperands())
2689 break; // Match fails if out of range child #.
2690 N = N.getOperand(ChildNo);
2691 NodeStack.push_back(N);
2695 case OPC_MoveParent:
2696 // Pop the current node off the NodeStack.
2697 NodeStack.pop_back();
2698 assert(!NodeStack.empty() && "Node stack imbalance!");
2699 N = NodeStack.back();
2703 if (!::CheckSame(MatcherTable, MatcherIndex, N, RecordedNodes)) break;
2706 case OPC_CheckChild0Same: case OPC_CheckChild1Same:
2707 case OPC_CheckChild2Same: case OPC_CheckChild3Same:
2708 if (!::CheckChildSame(MatcherTable, MatcherIndex, N, RecordedNodes,
2709 Opcode-OPC_CheckChild0Same))
2713 case OPC_CheckPatternPredicate:
2714 if (!::CheckPatternPredicate(MatcherTable, MatcherIndex, *this)) break;
2716 case OPC_CheckPredicate:
2717 if (!::CheckNodePredicate(MatcherTable, MatcherIndex, *this,
2721 case OPC_CheckComplexPat: {
2722 unsigned CPNum = MatcherTable[MatcherIndex++];
2723 unsigned RecNo = MatcherTable[MatcherIndex++];
2724 assert(RecNo < RecordedNodes.size() && "Invalid CheckComplexPat");
2726 // If target can modify DAG during matching, keep the matching state
2728 std::unique_ptr<MatchStateUpdater> MSU;
2729 if (ComplexPatternFuncMutatesDAG())
2730 MSU.reset(new MatchStateUpdater(*CurDAG, RecordedNodes,
2733 if (!CheckComplexPattern(NodeToMatch, RecordedNodes[RecNo].second,
2734 RecordedNodes[RecNo].first, CPNum,
2739 case OPC_CheckOpcode:
2740 if (!::CheckOpcode(MatcherTable, MatcherIndex, N.getNode())) break;
2744 if (!::CheckType(MatcherTable, MatcherIndex, N, getTargetLowering()))
2748 case OPC_SwitchOpcode: {
2749 unsigned CurNodeOpcode = N.getOpcode();
2750 unsigned SwitchStart = MatcherIndex-1; (void)SwitchStart;
2753 // Get the size of this case.
2754 CaseSize = MatcherTable[MatcherIndex++];
2756 CaseSize = GetVBR(CaseSize, MatcherTable, MatcherIndex);
2757 if (CaseSize == 0) break;
2759 uint16_t Opc = MatcherTable[MatcherIndex++];
2760 Opc |= (unsigned short)MatcherTable[MatcherIndex++] << 8;
2762 // If the opcode matches, then we will execute this case.
2763 if (CurNodeOpcode == Opc)
2766 // Otherwise, skip over this case.
2767 MatcherIndex += CaseSize;
2770 // If no cases matched, bail out.
2771 if (CaseSize == 0) break;
2773 // Otherwise, execute the case we found.
2774 DEBUG(dbgs() << " OpcodeSwitch from " << SwitchStart
2775 << " to " << MatcherIndex << "\n");
2779 case OPC_SwitchType: {
2780 MVT CurNodeVT = N.getSimpleValueType();
2781 unsigned SwitchStart = MatcherIndex-1; (void)SwitchStart;
2784 // Get the size of this case.
2785 CaseSize = MatcherTable[MatcherIndex++];
2787 CaseSize = GetVBR(CaseSize, MatcherTable, MatcherIndex);
2788 if (CaseSize == 0) break;
2790 MVT CaseVT = (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2791 if (CaseVT == MVT::iPTR)
2792 CaseVT = getTargetLowering()->getPointerTy();
2794 // If the VT matches, then we will execute this case.
2795 if (CurNodeVT == CaseVT)
2798 // Otherwise, skip over this case.
2799 MatcherIndex += CaseSize;
2802 // If no cases matched, bail out.
2803 if (CaseSize == 0) break;
2805 // Otherwise, execute the case we found.
2806 DEBUG(dbgs() << " TypeSwitch[" << EVT(CurNodeVT).getEVTString()
2807 << "] from " << SwitchStart << " to " << MatcherIndex<<'\n');
2810 case OPC_CheckChild0Type: case OPC_CheckChild1Type:
2811 case OPC_CheckChild2Type: case OPC_CheckChild3Type:
2812 case OPC_CheckChild4Type: case OPC_CheckChild5Type:
2813 case OPC_CheckChild6Type: case OPC_CheckChild7Type:
2814 if (!::CheckChildType(MatcherTable, MatcherIndex, N, getTargetLowering(),
2815 Opcode-OPC_CheckChild0Type))
2818 case OPC_CheckCondCode:
2819 if (!::CheckCondCode(MatcherTable, MatcherIndex, N)) break;
2821 case OPC_CheckValueType:
2822 if (!::CheckValueType(MatcherTable, MatcherIndex, N, getTargetLowering()))
2825 case OPC_CheckInteger:
2826 if (!::CheckInteger(MatcherTable, MatcherIndex, N)) break;
2828 case OPC_CheckChild0Integer: case OPC_CheckChild1Integer:
2829 case OPC_CheckChild2Integer: case OPC_CheckChild3Integer:
2830 case OPC_CheckChild4Integer:
2831 if (!::CheckChildInteger(MatcherTable, MatcherIndex, N,
2832 Opcode-OPC_CheckChild0Integer)) break;
2834 case OPC_CheckAndImm:
2835 if (!::CheckAndImm(MatcherTable, MatcherIndex, N, *this)) break;
2837 case OPC_CheckOrImm:
2838 if (!::CheckOrImm(MatcherTable, MatcherIndex, N, *this)) break;
2841 case OPC_CheckFoldableChainNode: {
2842 assert(NodeStack.size() != 1 && "No parent node");
2843 // Verify that all intermediate nodes between the root and this one have
2845 bool HasMultipleUses = false;
2846 for (unsigned i = 1, e = NodeStack.size()-1; i != e; ++i)
2847 if (!NodeStack[i].hasOneUse()) {
2848 HasMultipleUses = true;
2851 if (HasMultipleUses) break;
2853 // Check to see that the target thinks this is profitable to fold and that
2854 // we can fold it without inducing cycles in the graph.
2855 if (!IsProfitableToFold(N, NodeStack[NodeStack.size()-2].getNode(),
2857 !IsLegalToFold(N, NodeStack[NodeStack.size()-2].getNode(),
2858 NodeToMatch, OptLevel,
2859 true/*We validate our own chains*/))
2864 case OPC_EmitInteger: {
2865 MVT::SimpleValueType VT =
2866 (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2867 int64_t Val = MatcherTable[MatcherIndex++];
2869 Val = GetVBR(Val, MatcherTable, MatcherIndex);
2870 RecordedNodes.push_back(std::pair<SDValue, SDNode*>(
2871 CurDAG->getTargetConstant(Val, VT), nullptr));
2874 case OPC_EmitRegister: {
2875 MVT::SimpleValueType VT =
2876 (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2877 unsigned RegNo = MatcherTable[MatcherIndex++];
2878 RecordedNodes.push_back(std::pair<SDValue, SDNode*>(
2879 CurDAG->getRegister(RegNo, VT), nullptr));
2882 case OPC_EmitRegister2: {
2883 // For targets w/ more than 256 register names, the register enum
2884 // values are stored in two bytes in the matcher table (just like
2886 MVT::SimpleValueType VT =
2887 (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2888 unsigned RegNo = MatcherTable[MatcherIndex++];
2889 RegNo |= MatcherTable[MatcherIndex++] << 8;
2890 RecordedNodes.push_back(std::pair<SDValue, SDNode*>(
2891 CurDAG->getRegister(RegNo, VT), nullptr));
2895 case OPC_EmitConvertToTarget: {
2896 // Convert from IMM/FPIMM to target version.
2897 unsigned RecNo = MatcherTable[MatcherIndex++];
2898 assert(RecNo < RecordedNodes.size() && "Invalid EmitConvertToTarget");
2899 SDValue Imm = RecordedNodes[RecNo].first;
2901 if (Imm->getOpcode() == ISD::Constant) {
2902 const ConstantInt *Val=cast<ConstantSDNode>(Imm)->getConstantIntValue();
2903 Imm = CurDAG->getConstant(*Val, Imm.getValueType(), true);
2904 } else if (Imm->getOpcode() == ISD::ConstantFP) {
2905 const ConstantFP *Val=cast<ConstantFPSDNode>(Imm)->getConstantFPValue();
2906 Imm = CurDAG->getConstantFP(*Val, Imm.getValueType(), true);
2909 RecordedNodes.push_back(std::make_pair(Imm, RecordedNodes[RecNo].second));
2913 case OPC_EmitMergeInputChains1_0: // OPC_EmitMergeInputChains, 1, 0
2914 case OPC_EmitMergeInputChains1_1: { // OPC_EmitMergeInputChains, 1, 1
2915 // These are space-optimized forms of OPC_EmitMergeInputChains.
2916 assert(!InputChain.getNode() &&
2917 "EmitMergeInputChains should be the first chain producing node");
2918 assert(ChainNodesMatched.empty() &&
2919 "Should only have one EmitMergeInputChains per match");
2921 // Read all of the chained nodes.
2922 unsigned RecNo = Opcode == OPC_EmitMergeInputChains1_1;
2923 assert(RecNo < RecordedNodes.size() && "Invalid EmitMergeInputChains");
2924 ChainNodesMatched.push_back(RecordedNodes[RecNo].first.getNode());
2926 // FIXME: What if other value results of the node have uses not matched
2928 if (ChainNodesMatched.back() != NodeToMatch &&
2929 !RecordedNodes[RecNo].first.hasOneUse()) {
2930 ChainNodesMatched.clear();
2934 // Merge the input chains if they are not intra-pattern references.
2935 InputChain = HandleMergeInputChains(ChainNodesMatched, CurDAG);
2937 if (!InputChain.getNode())
2938 break; // Failed to merge.
2942 case OPC_EmitMergeInputChains: {
2943 assert(!InputChain.getNode() &&
2944 "EmitMergeInputChains should be the first chain producing node");
2945 // This node gets a list of nodes we matched in the input that have
2946 // chains. We want to token factor all of the input chains to these nodes
2947 // together. However, if any of the input chains is actually one of the
2948 // nodes matched in this pattern, then we have an intra-match reference.
2949 // Ignore these because the newly token factored chain should not refer to
2951 unsigned NumChains = MatcherTable[MatcherIndex++];
2952 assert(NumChains != 0 && "Can't TF zero chains");
2954 assert(ChainNodesMatched.empty() &&
2955 "Should only have one EmitMergeInputChains per match");
2957 // Read all of the chained nodes.
2958 for (unsigned i = 0; i != NumChains; ++i) {
2959 unsigned RecNo = MatcherTable[MatcherIndex++];
2960 assert(RecNo < RecordedNodes.size() && "Invalid EmitMergeInputChains");
2961 ChainNodesMatched.push_back(RecordedNodes[RecNo].first.getNode());
2963 // FIXME: What if other value results of the node have uses not matched
2965 if (ChainNodesMatched.back() != NodeToMatch &&
2966 !RecordedNodes[RecNo].first.hasOneUse()) {
2967 ChainNodesMatched.clear();
2972 // If the inner loop broke out, the match fails.
2973 if (ChainNodesMatched.empty())
2976 // Merge the input chains if they are not intra-pattern references.
2977 InputChain = HandleMergeInputChains(ChainNodesMatched, CurDAG);
2979 if (!InputChain.getNode())
2980 break; // Failed to merge.
2985 case OPC_EmitCopyToReg: {
2986 unsigned RecNo = MatcherTable[MatcherIndex++];
2987 assert(RecNo < RecordedNodes.size() && "Invalid EmitCopyToReg");
2988 unsigned DestPhysReg = MatcherTable[MatcherIndex++];
2990 if (!InputChain.getNode())
2991 InputChain = CurDAG->getEntryNode();
2993 InputChain = CurDAG->getCopyToReg(InputChain, SDLoc(NodeToMatch),
2994 DestPhysReg, RecordedNodes[RecNo].first,
2997 InputGlue = InputChain.getValue(1);
3001 case OPC_EmitNodeXForm: {
3002 unsigned XFormNo = MatcherTable[MatcherIndex++];
3003 unsigned RecNo = MatcherTable[MatcherIndex++];
3004 assert(RecNo < RecordedNodes.size() && "Invalid EmitNodeXForm");
3005 SDValue Res = RunSDNodeXForm(RecordedNodes[RecNo].first, XFormNo);
3006 RecordedNodes.push_back(std::pair<SDValue,SDNode*>(Res, nullptr));
3011 case OPC_MorphNodeTo: {
3012 uint16_t TargetOpc = MatcherTable[MatcherIndex++];
3013 TargetOpc |= (unsigned short)MatcherTable[MatcherIndex++] << 8;
3014 unsigned EmitNodeInfo = MatcherTable[MatcherIndex++];
3015 // Get the result VT list.
3016 unsigned NumVTs = MatcherTable[MatcherIndex++];
3017 SmallVector<EVT, 4> VTs;
3018 for (unsigned i = 0; i != NumVTs; ++i) {
3019 MVT::SimpleValueType VT =
3020 (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
3021 if (VT == MVT::iPTR) VT = getTargetLowering()->getPointerTy().SimpleTy;
3025 if (EmitNodeInfo & OPFL_Chain)
3026 VTs.push_back(MVT::Other);
3027 if (EmitNodeInfo & OPFL_GlueOutput)
3028 VTs.push_back(MVT::Glue);
3030 // This is hot code, so optimize the two most common cases of 1 and 2
3033 if (VTs.size() == 1)
3034 VTList = CurDAG->getVTList(VTs[0]);
3035 else if (VTs.size() == 2)
3036 VTList = CurDAG->getVTList(VTs[0], VTs[1]);
3038 VTList = CurDAG->getVTList(VTs);
3040 // Get the operand list.
3041 unsigned NumOps = MatcherTable[MatcherIndex++];
3042 SmallVector<SDValue, 8> Ops;
3043 for (unsigned i = 0; i != NumOps; ++i) {
3044 unsigned RecNo = MatcherTable[MatcherIndex++];
3046 RecNo = GetVBR(RecNo, MatcherTable, MatcherIndex);
3048 assert(RecNo < RecordedNodes.size() && "Invalid EmitNode");
3049 Ops.push_back(RecordedNodes[RecNo].first);
3052 // If there are variadic operands to add, handle them now.
3053 if (EmitNodeInfo & OPFL_VariadicInfo) {
3054 // Determine the start index to copy from.
3055 unsigned FirstOpToCopy = getNumFixedFromVariadicInfo(EmitNodeInfo);
3056 FirstOpToCopy += (EmitNodeInfo & OPFL_Chain) ? 1 : 0;
3057 assert(NodeToMatch->getNumOperands() >= FirstOpToCopy &&
3058 "Invalid variadic node");
3059 // Copy all of the variadic operands, not including a potential glue
3061 for (unsigned i = FirstOpToCopy, e = NodeToMatch->getNumOperands();
3063 SDValue V = NodeToMatch->getOperand(i);
3064 if (V.getValueType() == MVT::Glue) break;
3069 // If this has chain/glue inputs, add them.
3070 if (EmitNodeInfo & OPFL_Chain)
3071 Ops.push_back(InputChain);
3072 if ((EmitNodeInfo & OPFL_GlueInput) && InputGlue.getNode() != nullptr)
3073 Ops.push_back(InputGlue);
3076 SDNode *Res = nullptr;
3077 if (Opcode != OPC_MorphNodeTo) {
3078 // If this is a normal EmitNode command, just create the new node and
3079 // add the results to the RecordedNodes list.
3080 Res = CurDAG->getMachineNode(TargetOpc, SDLoc(NodeToMatch),
3083 // Add all the non-glue/non-chain results to the RecordedNodes list.
3084 for (unsigned i = 0, e = VTs.size(); i != e; ++i) {
3085 if (VTs[i] == MVT::Other || VTs[i] == MVT::Glue) break;
3086 RecordedNodes.push_back(std::pair<SDValue,SDNode*>(SDValue(Res, i),
3090 } else if (NodeToMatch->getOpcode() != ISD::DELETED_NODE) {
3091 Res = MorphNode(NodeToMatch, TargetOpc, VTList, Ops, EmitNodeInfo);
3093 // NodeToMatch was eliminated by CSE when the target changed the DAG.
3094 // We will visit the equivalent node later.
3095 DEBUG(dbgs() << "Node was eliminated by CSE\n");
3099 // If the node had chain/glue results, update our notion of the current
3101 if (EmitNodeInfo & OPFL_GlueOutput) {
3102 InputGlue = SDValue(Res, VTs.size()-1);
3103 if (EmitNodeInfo & OPFL_Chain)
3104 InputChain = SDValue(Res, VTs.size()-2);
3105 } else if (EmitNodeInfo & OPFL_Chain)
3106 InputChain = SDValue(Res, VTs.size()-1);
3108 // If the OPFL_MemRefs glue is set on this node, slap all of the
3109 // accumulated memrefs onto it.
3111 // FIXME: This is vastly incorrect for patterns with multiple outputs
3112 // instructions that access memory and for ComplexPatterns that match
3114 if (EmitNodeInfo & OPFL_MemRefs) {
3115 // Only attach load or store memory operands if the generated
3116 // instruction may load or store.
3117 const MCInstrDesc &MCID =
3118 TM.getSubtargetImpl()->getInstrInfo()->get(TargetOpc);
3119 bool mayLoad = MCID.mayLoad();
3120 bool mayStore = MCID.mayStore();
3122 unsigned NumMemRefs = 0;
3123 for (SmallVectorImpl<MachineMemOperand *>::const_iterator I =
3124 MatchedMemRefs.begin(), E = MatchedMemRefs.end(); I != E; ++I) {
3125 if ((*I)->isLoad()) {
3128 } else if ((*I)->isStore()) {
3136 MachineSDNode::mmo_iterator MemRefs =
3137 MF->allocateMemRefsArray(NumMemRefs);
3139 MachineSDNode::mmo_iterator MemRefsPos = MemRefs;
3140 for (SmallVectorImpl<MachineMemOperand *>::const_iterator I =
3141 MatchedMemRefs.begin(), E = MatchedMemRefs.end(); I != E; ++I) {
3142 if ((*I)->isLoad()) {
3145 } else if ((*I)->isStore()) {
3153 cast<MachineSDNode>(Res)
3154 ->setMemRefs(MemRefs, MemRefs + NumMemRefs);
3158 << (Opcode == OPC_MorphNodeTo ? "Morphed" : "Created")
3159 << " node: "; Res->dump(CurDAG); dbgs() << "\n");
3161 // If this was a MorphNodeTo then we're completely done!
3162 if (Opcode == OPC_MorphNodeTo) {
3163 // Update chain and glue uses.
3164 UpdateChainsAndGlue(NodeToMatch, InputChain, ChainNodesMatched,
3165 InputGlue, GlueResultNodesMatched, true);
3172 case OPC_MarkGlueResults: {
3173 unsigned NumNodes = MatcherTable[MatcherIndex++];
3175 // Read and remember all the glue-result nodes.
3176 for (unsigned i = 0; i != NumNodes; ++i) {
3177 unsigned RecNo = MatcherTable[MatcherIndex++];
3179 RecNo = GetVBR(RecNo, MatcherTable, MatcherIndex);
3181 assert(RecNo < RecordedNodes.size() && "Invalid MarkGlueResults");
3182 GlueResultNodesMatched.push_back(RecordedNodes[RecNo].first.getNode());
3187 case OPC_CompleteMatch: {
3188 // The match has been completed, and any new nodes (if any) have been
3189 // created. Patch up references to the matched dag to use the newly
3191 unsigned NumResults = MatcherTable[MatcherIndex++];
3193 for (unsigned i = 0; i != NumResults; ++i) {
3194 unsigned ResSlot = MatcherTable[MatcherIndex++];
3196 ResSlot = GetVBR(ResSlot, MatcherTable, MatcherIndex);
3198 assert(ResSlot < RecordedNodes.size() && "Invalid CompleteMatch");
3199 SDValue Res = RecordedNodes[ResSlot].first;
3201 assert(i < NodeToMatch->getNumValues() &&
3202 NodeToMatch->getValueType(i) != MVT::Other &&
3203 NodeToMatch->getValueType(i) != MVT::Glue &&
3204 "Invalid number of results to complete!");
3205 assert((NodeToMatch->getValueType(i) == Res.getValueType() ||
3206 NodeToMatch->getValueType(i) == MVT::iPTR ||
3207 Res.getValueType() == MVT::iPTR ||
3208 NodeToMatch->getValueType(i).getSizeInBits() ==
3209 Res.getValueType().getSizeInBits()) &&
3210 "invalid replacement");
3211 CurDAG->ReplaceAllUsesOfValueWith(SDValue(NodeToMatch, i), Res);
3214 // If the root node defines glue, add it to the glue nodes to update list.
3215 if (NodeToMatch->getValueType(NodeToMatch->getNumValues()-1) == MVT::Glue)
3216 GlueResultNodesMatched.push_back(NodeToMatch);
3218 // Update chain and glue uses.
3219 UpdateChainsAndGlue(NodeToMatch, InputChain, ChainNodesMatched,
3220 InputGlue, GlueResultNodesMatched, false);
3222 assert(NodeToMatch->use_empty() &&
3223 "Didn't replace all uses of the node?");
3225 // FIXME: We just return here, which interacts correctly with SelectRoot
3226 // above. We should fix this to not return an SDNode* anymore.
3231 // If the code reached this point, then the match failed. See if there is
3232 // another child to try in the current 'Scope', otherwise pop it until we
3233 // find a case to check.
3234 DEBUG(dbgs() << " Match failed at index " << CurrentOpcodeIndex << "\n");
3235 ++NumDAGIselRetries;
3237 if (MatchScopes.empty()) {
3238 CannotYetSelect(NodeToMatch);
3242 // Restore the interpreter state back to the point where the scope was
3244 MatchScope &LastScope = MatchScopes.back();
3245 RecordedNodes.resize(LastScope.NumRecordedNodes);
3247 NodeStack.append(LastScope.NodeStack.begin(), LastScope.NodeStack.end());
3248 N = NodeStack.back();
3250 if (LastScope.NumMatchedMemRefs != MatchedMemRefs.size())
3251 MatchedMemRefs.resize(LastScope.NumMatchedMemRefs);
3252 MatcherIndex = LastScope.FailIndex;
3254 DEBUG(dbgs() << " Continuing at " << MatcherIndex << "\n");
3256 InputChain = LastScope.InputChain;
3257 InputGlue = LastScope.InputGlue;
3258 if (!LastScope.HasChainNodesMatched)
3259 ChainNodesMatched.clear();
3260 if (!LastScope.HasGlueResultNodesMatched)
3261 GlueResultNodesMatched.clear();
3263 // Check to see what the offset is at the new MatcherIndex. If it is zero
3264 // we have reached the end of this scope, otherwise we have another child
3265 // in the current scope to try.
3266 unsigned NumToSkip = MatcherTable[MatcherIndex++];
3267 if (NumToSkip & 128)
3268 NumToSkip = GetVBR(NumToSkip, MatcherTable, MatcherIndex);
3270 // If we have another child in this scope to match, update FailIndex and
3272 if (NumToSkip != 0) {
3273 LastScope.FailIndex = MatcherIndex+NumToSkip;
3277 // End of this scope, pop it and try the next child in the containing
3279 MatchScopes.pop_back();
3286 void SelectionDAGISel::CannotYetSelect(SDNode *N) {
3288 raw_string_ostream Msg(msg);
3289 Msg << "Cannot select: ";
3291 if (N->getOpcode() != ISD::INTRINSIC_W_CHAIN &&
3292 N->getOpcode() != ISD::INTRINSIC_WO_CHAIN &&
3293 N->getOpcode() != ISD::INTRINSIC_VOID) {
3294 N->printrFull(Msg, CurDAG);
3295 Msg << "\nIn function: " << MF->getName();
3297 bool HasInputChain = N->getOperand(0).getValueType() == MVT::Other;
3299 cast<ConstantSDNode>(N->getOperand(HasInputChain))->getZExtValue();
3300 if (iid < Intrinsic::num_intrinsics)
3301 Msg << "intrinsic %" << Intrinsic::getName((Intrinsic::ID)iid);
3302 else if (const TargetIntrinsicInfo *TII = TM.getIntrinsicInfo())
3303 Msg << "target intrinsic %" << TII->getName(iid);
3305 Msg << "unknown intrinsic #" << iid;
3307 report_fatal_error(Msg.str());
3310 char SelectionDAGISel::ID = 0;