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 #define DEBUG_TYPE "isel"
15 #include "ScheduleDAGSDNodes.h"
16 #include "SelectionDAGBuilder.h"
17 #include "llvm/Constants.h"
18 #include "llvm/DebugInfo.h"
19 #include "llvm/Function.h"
20 #include "llvm/InlineAsm.h"
21 #include "llvm/Instructions.h"
22 #include "llvm/Intrinsics.h"
23 #include "llvm/IntrinsicInst.h"
24 #include "llvm/LLVMContext.h"
25 #include "llvm/Module.h"
26 #include "llvm/Analysis/AliasAnalysis.h"
27 #include "llvm/Analysis/BranchProbabilityInfo.h"
28 #include "llvm/CodeGen/FastISel.h"
29 #include "llvm/CodeGen/FunctionLoweringInfo.h"
30 #include "llvm/CodeGen/GCStrategy.h"
31 #include "llvm/CodeGen/GCMetadata.h"
32 #include "llvm/CodeGen/MachineFrameInfo.h"
33 #include "llvm/CodeGen/MachineFunction.h"
34 #include "llvm/CodeGen/MachineInstrBuilder.h"
35 #include "llvm/CodeGen/MachineModuleInfo.h"
36 #include "llvm/CodeGen/MachineRegisterInfo.h"
37 #include "llvm/CodeGen/ScheduleHazardRecognizer.h"
38 #include "llvm/CodeGen/SchedulerRegistry.h"
39 #include "llvm/CodeGen/SelectionDAG.h"
40 #include "llvm/CodeGen/SelectionDAGISel.h"
41 #include "llvm/Target/TargetRegisterInfo.h"
42 #include "llvm/Target/TargetIntrinsicInfo.h"
43 #include "llvm/Target/TargetInstrInfo.h"
44 #include "llvm/Target/TargetLibraryInfo.h"
45 #include "llvm/Target/TargetLowering.h"
46 #include "llvm/Target/TargetMachine.h"
47 #include "llvm/Target/TargetOptions.h"
48 #include "llvm/Target/TargetSubtargetInfo.h"
49 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
50 #include "llvm/Support/Compiler.h"
51 #include "llvm/Support/Debug.h"
52 #include "llvm/Support/ErrorHandling.h"
53 #include "llvm/Support/Timer.h"
54 #include "llvm/Support/raw_ostream.h"
55 #include "llvm/ADT/PostOrderIterator.h"
56 #include "llvm/ADT/Statistic.h"
60 STATISTIC(NumFastIselFailures, "Number of instructions fast isel failed on");
61 STATISTIC(NumFastIselSuccess, "Number of instructions fast isel selected");
62 STATISTIC(NumFastIselBlocks, "Number of blocks selected entirely by fast isel");
63 STATISTIC(NumDAGBlocks, "Number of blocks selected using DAG");
64 STATISTIC(NumDAGIselRetries,"Number of times dag isel has to try another path");
68 EnableFastISelVerbose2("fast-isel-verbose2", cl::Hidden,
69 cl::desc("Enable extra verbose messages in the \"fast\" "
70 "instruction selector"));
72 STATISTIC(NumFastIselFailRet,"Fast isel fails on Ret");
73 STATISTIC(NumFastIselFailBr,"Fast isel fails on Br");
74 STATISTIC(NumFastIselFailSwitch,"Fast isel fails on Switch");
75 STATISTIC(NumFastIselFailIndirectBr,"Fast isel fails on IndirectBr");
76 STATISTIC(NumFastIselFailInvoke,"Fast isel fails on Invoke");
77 STATISTIC(NumFastIselFailResume,"Fast isel fails on Resume");
78 STATISTIC(NumFastIselFailUnreachable,"Fast isel fails on Unreachable");
80 // Standard binary operators...
81 STATISTIC(NumFastIselFailAdd,"Fast isel fails on Add");
82 STATISTIC(NumFastIselFailFAdd,"Fast isel fails on FAdd");
83 STATISTIC(NumFastIselFailSub,"Fast isel fails on Sub");
84 STATISTIC(NumFastIselFailFSub,"Fast isel fails on FSub");
85 STATISTIC(NumFastIselFailMul,"Fast isel fails on Mul");
86 STATISTIC(NumFastIselFailFMul,"Fast isel fails on FMul");
87 STATISTIC(NumFastIselFailUDiv,"Fast isel fails on UDiv");
88 STATISTIC(NumFastIselFailSDiv,"Fast isel fails on SDiv");
89 STATISTIC(NumFastIselFailFDiv,"Fast isel fails on FDiv");
90 STATISTIC(NumFastIselFailURem,"Fast isel fails on URem");
91 STATISTIC(NumFastIselFailSRem,"Fast isel fails on SRem");
92 STATISTIC(NumFastIselFailFRem,"Fast isel fails on FRem");
94 // Logical operators...
95 STATISTIC(NumFastIselFailAnd,"Fast isel fails on And");
96 STATISTIC(NumFastIselFailOr,"Fast isel fails on Or");
97 STATISTIC(NumFastIselFailXor,"Fast isel fails on Xor");
99 // Memory instructions...
100 STATISTIC(NumFastIselFailAlloca,"Fast isel fails on Alloca");
101 STATISTIC(NumFastIselFailLoad,"Fast isel fails on Load");
102 STATISTIC(NumFastIselFailStore,"Fast isel fails on Store");
103 STATISTIC(NumFastIselFailAtomicCmpXchg,"Fast isel fails on AtomicCmpXchg");
104 STATISTIC(NumFastIselFailAtomicRMW,"Fast isel fails on AtomicRWM");
105 STATISTIC(NumFastIselFailFence,"Fast isel fails on Frence");
106 STATISTIC(NumFastIselFailGetElementPtr,"Fast isel fails on GetElementPtr");
108 // Convert instructions...
109 STATISTIC(NumFastIselFailTrunc,"Fast isel fails on Trunc");
110 STATISTIC(NumFastIselFailZExt,"Fast isel fails on ZExt");
111 STATISTIC(NumFastIselFailSExt,"Fast isel fails on SExt");
112 STATISTIC(NumFastIselFailFPTrunc,"Fast isel fails on FPTrunc");
113 STATISTIC(NumFastIselFailFPExt,"Fast isel fails on FPExt");
114 STATISTIC(NumFastIselFailFPToUI,"Fast isel fails on FPToUI");
115 STATISTIC(NumFastIselFailFPToSI,"Fast isel fails on FPToSI");
116 STATISTIC(NumFastIselFailUIToFP,"Fast isel fails on UIToFP");
117 STATISTIC(NumFastIselFailSIToFP,"Fast isel fails on SIToFP");
118 STATISTIC(NumFastIselFailIntToPtr,"Fast isel fails on IntToPtr");
119 STATISTIC(NumFastIselFailPtrToInt,"Fast isel fails on PtrToInt");
120 STATISTIC(NumFastIselFailBitCast,"Fast isel fails on BitCast");
122 // Other instructions...
123 STATISTIC(NumFastIselFailICmp,"Fast isel fails on ICmp");
124 STATISTIC(NumFastIselFailFCmp,"Fast isel fails on FCmp");
125 STATISTIC(NumFastIselFailPHI,"Fast isel fails on PHI");
126 STATISTIC(NumFastIselFailSelect,"Fast isel fails on Select");
127 STATISTIC(NumFastIselFailCall,"Fast isel fails on Call");
128 STATISTIC(NumFastIselFailShl,"Fast isel fails on Shl");
129 STATISTIC(NumFastIselFailLShr,"Fast isel fails on LShr");
130 STATISTIC(NumFastIselFailAShr,"Fast isel fails on AShr");
131 STATISTIC(NumFastIselFailVAArg,"Fast isel fails on VAArg");
132 STATISTIC(NumFastIselFailExtractElement,"Fast isel fails on ExtractElement");
133 STATISTIC(NumFastIselFailInsertElement,"Fast isel fails on InsertElement");
134 STATISTIC(NumFastIselFailShuffleVector,"Fast isel fails on ShuffleVector");
135 STATISTIC(NumFastIselFailExtractValue,"Fast isel fails on ExtractValue");
136 STATISTIC(NumFastIselFailInsertValue,"Fast isel fails on InsertValue");
137 STATISTIC(NumFastIselFailLandingPad,"Fast isel fails on LandingPad");
141 EnableFastISelVerbose("fast-isel-verbose", cl::Hidden,
142 cl::desc("Enable verbose messages in the \"fast\" "
143 "instruction selector"));
145 EnableFastISelAbort("fast-isel-abort", cl::Hidden,
146 cl::desc("Enable abort calls when \"fast\" instruction fails"));
150 cl::desc("use Machine Branch Probability Info"),
151 cl::init(true), cl::Hidden);
155 ViewDAGCombine1("view-dag-combine1-dags", cl::Hidden,
156 cl::desc("Pop up a window to show dags before the first "
157 "dag combine pass"));
159 ViewLegalizeTypesDAGs("view-legalize-types-dags", cl::Hidden,
160 cl::desc("Pop up a window to show dags before legalize types"));
162 ViewLegalizeDAGs("view-legalize-dags", cl::Hidden,
163 cl::desc("Pop up a window to show dags before legalize"));
165 ViewDAGCombine2("view-dag-combine2-dags", cl::Hidden,
166 cl::desc("Pop up a window to show dags before the second "
167 "dag combine pass"));
169 ViewDAGCombineLT("view-dag-combine-lt-dags", cl::Hidden,
170 cl::desc("Pop up a window to show dags before the post legalize types"
171 " dag combine pass"));
173 ViewISelDAGs("view-isel-dags", cl::Hidden,
174 cl::desc("Pop up a window to show isel dags as they are selected"));
176 ViewSchedDAGs("view-sched-dags", cl::Hidden,
177 cl::desc("Pop up a window to show sched dags as they are processed"));
179 ViewSUnitDAGs("view-sunit-dags", cl::Hidden,
180 cl::desc("Pop up a window to show SUnit dags after they are processed"));
182 static const bool ViewDAGCombine1 = false,
183 ViewLegalizeTypesDAGs = false, ViewLegalizeDAGs = false,
184 ViewDAGCombine2 = false,
185 ViewDAGCombineLT = false,
186 ViewISelDAGs = false, ViewSchedDAGs = false,
187 ViewSUnitDAGs = false;
190 //===---------------------------------------------------------------------===//
192 /// RegisterScheduler class - Track the registration of instruction schedulers.
194 //===---------------------------------------------------------------------===//
195 MachinePassRegistry RegisterScheduler::Registry;
197 //===---------------------------------------------------------------------===//
199 /// ISHeuristic command line option for instruction schedulers.
201 //===---------------------------------------------------------------------===//
202 static cl::opt<RegisterScheduler::FunctionPassCtor, false,
203 RegisterPassParser<RegisterScheduler> >
204 ISHeuristic("pre-RA-sched",
205 cl::init(&createDefaultScheduler),
206 cl::desc("Instruction schedulers available (before register"
209 static RegisterScheduler
210 defaultListDAGScheduler("default", "Best scheduler for the target",
211 createDefaultScheduler);
214 //===--------------------------------------------------------------------===//
215 /// createDefaultScheduler - This creates an instruction scheduler appropriate
217 ScheduleDAGSDNodes* createDefaultScheduler(SelectionDAGISel *IS,
218 CodeGenOpt::Level OptLevel) {
219 const TargetLowering &TLI = IS->getTargetLowering();
220 const TargetSubtargetInfo &ST = IS->TM.getSubtarget<TargetSubtargetInfo>();
222 if (OptLevel == CodeGenOpt::None || ST.enableMachineScheduler() ||
223 TLI.getSchedulingPreference() == Sched::Source)
224 return createSourceListDAGScheduler(IS, OptLevel);
225 if (TLI.getSchedulingPreference() == Sched::RegPressure)
226 return createBURRListDAGScheduler(IS, OptLevel);
227 if (TLI.getSchedulingPreference() == Sched::Hybrid)
228 return createHybridListDAGScheduler(IS, OptLevel);
229 if (TLI.getSchedulingPreference() == Sched::VLIW)
230 return createVLIWDAGScheduler(IS, OptLevel);
231 assert(TLI.getSchedulingPreference() == Sched::ILP &&
232 "Unknown sched type!");
233 return createILPListDAGScheduler(IS, OptLevel);
237 // EmitInstrWithCustomInserter - This method should be implemented by targets
238 // that mark instructions with the 'usesCustomInserter' flag. These
239 // instructions are special in various ways, which require special support to
240 // insert. The specified MachineInstr is created but not inserted into any
241 // basic blocks, and this method is called to expand it into a sequence of
242 // instructions, potentially also creating new basic blocks and control flow.
243 // When new basic blocks are inserted and the edges from MBB to its successors
244 // are modified, the method should insert pairs of <OldSucc, NewSucc> into the
247 TargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
248 MachineBasicBlock *MBB) const {
250 dbgs() << "If a target marks an instruction with "
251 "'usesCustomInserter', it must implement "
252 "TargetLowering::EmitInstrWithCustomInserter!";
257 void TargetLowering::AdjustInstrPostInstrSelection(MachineInstr *MI,
258 SDNode *Node) const {
259 assert(!MI->hasPostISelHook() &&
260 "If a target marks an instruction with 'hasPostISelHook', "
261 "it must implement TargetLowering::AdjustInstrPostInstrSelection!");
264 //===----------------------------------------------------------------------===//
265 // SelectionDAGISel code
266 //===----------------------------------------------------------------------===//
268 SelectionDAGISel::SelectionDAGISel(const TargetMachine &tm,
269 CodeGenOpt::Level OL) :
270 MachineFunctionPass(ID), TM(tm), TLI(*tm.getTargetLowering()),
271 FuncInfo(new FunctionLoweringInfo(TLI)),
272 CurDAG(new SelectionDAG(tm, OL)),
273 SDB(new SelectionDAGBuilder(*CurDAG, *FuncInfo, OL)),
277 initializeGCModuleInfoPass(*PassRegistry::getPassRegistry());
278 initializeAliasAnalysisAnalysisGroup(*PassRegistry::getPassRegistry());
279 initializeBranchProbabilityInfoPass(*PassRegistry::getPassRegistry());
280 initializeTargetLibraryInfoPass(*PassRegistry::getPassRegistry());
283 SelectionDAGISel::~SelectionDAGISel() {
289 void SelectionDAGISel::getAnalysisUsage(AnalysisUsage &AU) const {
290 AU.addRequired<AliasAnalysis>();
291 AU.addPreserved<AliasAnalysis>();
292 AU.addRequired<GCModuleInfo>();
293 AU.addPreserved<GCModuleInfo>();
294 AU.addRequired<TargetLibraryInfo>();
295 if (UseMBPI && OptLevel != CodeGenOpt::None)
296 AU.addRequired<BranchProbabilityInfo>();
297 MachineFunctionPass::getAnalysisUsage(AU);
300 /// SplitCriticalSideEffectEdges - Look for critical edges with a PHI value that
301 /// may trap on it. In this case we have to split the edge so that the path
302 /// through the predecessor block that doesn't go to the phi block doesn't
303 /// execute the possibly trapping instruction.
305 /// This is required for correctness, so it must be done at -O0.
307 static void SplitCriticalSideEffectEdges(Function &Fn, Pass *SDISel) {
308 // Loop for blocks with phi nodes.
309 for (Function::iterator BB = Fn.begin(), E = Fn.end(); BB != E; ++BB) {
310 PHINode *PN = dyn_cast<PHINode>(BB->begin());
311 if (PN == 0) continue;
314 // For each block with a PHI node, check to see if any of the input values
315 // are potentially trapping constant expressions. Constant expressions are
316 // the only potentially trapping value that can occur as the argument to a
318 for (BasicBlock::iterator I = BB->begin(); (PN = dyn_cast<PHINode>(I)); ++I)
319 for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
320 ConstantExpr *CE = dyn_cast<ConstantExpr>(PN->getIncomingValue(i));
321 if (CE == 0 || !CE->canTrap()) continue;
323 // The only case we have to worry about is when the edge is critical.
324 // Since this block has a PHI Node, we assume it has multiple input
325 // edges: check to see if the pred has multiple successors.
326 BasicBlock *Pred = PN->getIncomingBlock(i);
327 if (Pred->getTerminator()->getNumSuccessors() == 1)
330 // Okay, we have to split this edge.
331 SplitCriticalEdge(Pred->getTerminator(),
332 GetSuccessorNumber(Pred, BB), SDISel, true);
338 bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
339 // Do some sanity-checking on the command-line options.
340 assert((!EnableFastISelVerbose || TM.Options.EnableFastISel) &&
341 "-fast-isel-verbose requires -fast-isel");
342 assert((!EnableFastISelAbort || TM.Options.EnableFastISel) &&
343 "-fast-isel-abort requires -fast-isel");
345 const Function &Fn = *mf.getFunction();
346 const TargetInstrInfo &TII = *TM.getInstrInfo();
347 const TargetRegisterInfo &TRI = *TM.getRegisterInfo();
350 RegInfo = &MF->getRegInfo();
351 AA = &getAnalysis<AliasAnalysis>();
352 LibInfo = &getAnalysis<TargetLibraryInfo>();
353 GFI = Fn.hasGC() ? &getAnalysis<GCModuleInfo>().getFunctionInfo(Fn) : 0;
355 DEBUG(dbgs() << "\n\n\n=== " << Fn.getName() << "\n");
357 SplitCriticalSideEffectEdges(const_cast<Function&>(Fn), this);
360 FuncInfo->set(Fn, *MF);
362 if (UseMBPI && OptLevel != CodeGenOpt::None)
363 FuncInfo->BPI = &getAnalysis<BranchProbabilityInfo>();
367 SDB->init(GFI, *AA, LibInfo);
369 SelectAllBasicBlocks(Fn);
371 // If the first basic block in the function has live ins that need to be
372 // copied into vregs, emit the copies into the top of the block before
373 // emitting the code for the block.
374 MachineBasicBlock *EntryMBB = MF->begin();
375 RegInfo->EmitLiveInCopies(EntryMBB, TRI, TII);
377 DenseMap<unsigned, unsigned> LiveInMap;
378 if (!FuncInfo->ArgDbgValues.empty())
379 for (MachineRegisterInfo::livein_iterator LI = RegInfo->livein_begin(),
380 E = RegInfo->livein_end(); LI != E; ++LI)
382 LiveInMap.insert(std::make_pair(LI->first, LI->second));
384 // Insert DBG_VALUE instructions for function arguments to the entry block.
385 for (unsigned i = 0, e = FuncInfo->ArgDbgValues.size(); i != e; ++i) {
386 MachineInstr *MI = FuncInfo->ArgDbgValues[e-i-1];
387 unsigned Reg = MI->getOperand(0).getReg();
388 if (TargetRegisterInfo::isPhysicalRegister(Reg))
389 EntryMBB->insert(EntryMBB->begin(), MI);
391 MachineInstr *Def = RegInfo->getVRegDef(Reg);
392 MachineBasicBlock::iterator InsertPos = Def;
393 // FIXME: VR def may not be in entry block.
394 Def->getParent()->insert(llvm::next(InsertPos), MI);
397 // If Reg is live-in then update debug info to track its copy in a vreg.
398 DenseMap<unsigned, unsigned>::iterator LDI = LiveInMap.find(Reg);
399 if (LDI != LiveInMap.end()) {
400 MachineInstr *Def = RegInfo->getVRegDef(LDI->second);
401 MachineBasicBlock::iterator InsertPos = Def;
402 const MDNode *Variable =
403 MI->getOperand(MI->getNumOperands()-1).getMetadata();
404 unsigned Offset = MI->getOperand(1).getImm();
405 // Def is never a terminator here, so it is ok to increment InsertPos.
406 BuildMI(*EntryMBB, ++InsertPos, MI->getDebugLoc(),
407 TII.get(TargetOpcode::DBG_VALUE))
408 .addReg(LDI->second, RegState::Debug)
409 .addImm(Offset).addMetadata(Variable);
411 // If this vreg is directly copied into an exported register then
412 // that COPY instructions also need DBG_VALUE, if it is the only
413 // user of LDI->second.
414 MachineInstr *CopyUseMI = NULL;
415 for (MachineRegisterInfo::use_iterator
416 UI = RegInfo->use_begin(LDI->second);
417 MachineInstr *UseMI = UI.skipInstruction();) {
418 if (UseMI->isDebugValue()) continue;
419 if (UseMI->isCopy() && !CopyUseMI && UseMI->getParent() == EntryMBB) {
420 CopyUseMI = UseMI; continue;
422 // Otherwise this is another use or second copy use.
423 CopyUseMI = NULL; break;
426 MachineInstr *NewMI =
427 BuildMI(*MF, CopyUseMI->getDebugLoc(),
428 TII.get(TargetOpcode::DBG_VALUE))
429 .addReg(CopyUseMI->getOperand(0).getReg(), RegState::Debug)
430 .addImm(Offset).addMetadata(Variable);
431 MachineBasicBlock::iterator Pos = CopyUseMI;
432 EntryMBB->insertAfter(Pos, NewMI);
437 // Determine if there are any calls in this machine function.
438 MachineFrameInfo *MFI = MF->getFrameInfo();
439 if (!MFI->hasCalls()) {
440 for (MachineFunction::const_iterator
441 I = MF->begin(), E = MF->end(); I != E; ++I) {
442 const MachineBasicBlock *MBB = I;
443 for (MachineBasicBlock::const_iterator
444 II = MBB->begin(), IE = MBB->end(); II != IE; ++II) {
445 const MCInstrDesc &MCID = TM.getInstrInfo()->get(II->getOpcode());
447 if ((MCID.isCall() && !MCID.isReturn()) ||
448 II->isStackAligningInlineAsm()) {
449 MFI->setHasCalls(true);
457 // Determine if there is a call to setjmp in the machine function.
458 MF->setExposesReturnsTwice(Fn.callsFunctionThatReturnsTwice());
460 // Replace forward-declared registers with the registers containing
461 // the desired value.
462 MachineRegisterInfo &MRI = MF->getRegInfo();
463 for (DenseMap<unsigned, unsigned>::iterator
464 I = FuncInfo->RegFixups.begin(), E = FuncInfo->RegFixups.end();
466 unsigned From = I->first;
467 unsigned To = I->second;
468 // If To is also scheduled to be replaced, find what its ultimate
471 DenseMap<unsigned, unsigned>::iterator J = FuncInfo->RegFixups.find(To);
476 MRI.replaceRegWith(From, To);
479 // Freeze the set of reserved registers now that MachineFrameInfo has been
480 // set up. All the information required by getReservedRegs() should be
482 MRI.freezeReservedRegs(*MF);
484 // Release function-specific state. SDB and CurDAG are already cleared
491 void SelectionDAGISel::SelectBasicBlock(BasicBlock::const_iterator Begin,
492 BasicBlock::const_iterator End,
494 // Lower all of the non-terminator instructions. If a call is emitted
495 // as a tail call, cease emitting nodes for this block. Terminators
496 // are handled below.
497 for (BasicBlock::const_iterator I = Begin; I != End && !SDB->HasTailCall; ++I)
500 // Make sure the root of the DAG is up-to-date.
501 CurDAG->setRoot(SDB->getControlRoot());
502 HadTailCall = SDB->HasTailCall;
505 // Final step, emit the lowered DAG as machine code.
509 void SelectionDAGISel::ComputeLiveOutVRegInfo() {
510 SmallPtrSet<SDNode*, 128> VisitedNodes;
511 SmallVector<SDNode*, 128> Worklist;
513 Worklist.push_back(CurDAG->getRoot().getNode());
519 SDNode *N = Worklist.pop_back_val();
521 // If we've already seen this node, ignore it.
522 if (!VisitedNodes.insert(N))
525 // Otherwise, add all chain operands to the worklist.
526 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
527 if (N->getOperand(i).getValueType() == MVT::Other)
528 Worklist.push_back(N->getOperand(i).getNode());
530 // If this is a CopyToReg with a vreg dest, process it.
531 if (N->getOpcode() != ISD::CopyToReg)
534 unsigned DestReg = cast<RegisterSDNode>(N->getOperand(1))->getReg();
535 if (!TargetRegisterInfo::isVirtualRegister(DestReg))
538 // Ignore non-scalar or non-integer values.
539 SDValue Src = N->getOperand(2);
540 EVT SrcVT = Src.getValueType();
541 if (!SrcVT.isInteger() || SrcVT.isVector())
544 unsigned NumSignBits = CurDAG->ComputeNumSignBits(Src);
545 CurDAG->ComputeMaskedBits(Src, KnownZero, KnownOne);
546 FuncInfo->AddLiveOutRegInfo(DestReg, NumSignBits, KnownZero, KnownOne);
547 } while (!Worklist.empty());
550 void SelectionDAGISel::CodeGenAndEmitDAG() {
551 std::string GroupName;
552 if (TimePassesIsEnabled)
553 GroupName = "Instruction Selection and Scheduling";
554 std::string BlockName;
555 int BlockNumber = -1;
558 if (ViewDAGCombine1 || ViewLegalizeTypesDAGs || ViewLegalizeDAGs ||
559 ViewDAGCombine2 || ViewDAGCombineLT || ViewISelDAGs || ViewSchedDAGs ||
563 BlockNumber = FuncInfo->MBB->getNumber();
564 BlockName = MF->getName().str() + ":" +
565 FuncInfo->MBB->getBasicBlock()->getName().str();
567 DEBUG(dbgs() << "Initial selection DAG: BB#" << BlockNumber
568 << " '" << BlockName << "'\n"; CurDAG->dump());
570 if (ViewDAGCombine1) CurDAG->viewGraph("dag-combine1 input for " + BlockName);
572 // Run the DAG combiner in pre-legalize mode.
574 NamedRegionTimer T("DAG Combining 1", GroupName, TimePassesIsEnabled);
575 CurDAG->Combine(BeforeLegalizeTypes, *AA, OptLevel);
578 DEBUG(dbgs() << "Optimized lowered selection DAG: BB#" << BlockNumber
579 << " '" << BlockName << "'\n"; CurDAG->dump());
581 // Second step, hack on the DAG until it only uses operations and types that
582 // the target supports.
583 if (ViewLegalizeTypesDAGs) CurDAG->viewGraph("legalize-types input for " +
588 NamedRegionTimer T("Type Legalization", GroupName, TimePassesIsEnabled);
589 Changed = CurDAG->LegalizeTypes();
592 DEBUG(dbgs() << "Type-legalized selection DAG: BB#" << BlockNumber
593 << " '" << BlockName << "'\n"; CurDAG->dump());
596 if (ViewDAGCombineLT)
597 CurDAG->viewGraph("dag-combine-lt input for " + BlockName);
599 // Run the DAG combiner in post-type-legalize mode.
601 NamedRegionTimer T("DAG Combining after legalize types", GroupName,
602 TimePassesIsEnabled);
603 CurDAG->Combine(AfterLegalizeTypes, *AA, OptLevel);
606 DEBUG(dbgs() << "Optimized type-legalized selection DAG: BB#" << BlockNumber
607 << " '" << BlockName << "'\n"; CurDAG->dump());
611 NamedRegionTimer T("Vector Legalization", GroupName, TimePassesIsEnabled);
612 Changed = CurDAG->LegalizeVectors();
617 NamedRegionTimer T("Type Legalization 2", GroupName, TimePassesIsEnabled);
618 CurDAG->LegalizeTypes();
621 if (ViewDAGCombineLT)
622 CurDAG->viewGraph("dag-combine-lv input for " + BlockName);
624 // Run the DAG combiner in post-type-legalize mode.
626 NamedRegionTimer T("DAG Combining after legalize vectors", GroupName,
627 TimePassesIsEnabled);
628 CurDAG->Combine(AfterLegalizeVectorOps, *AA, OptLevel);
631 DEBUG(dbgs() << "Optimized vector-legalized selection DAG: BB#"
632 << BlockNumber << " '" << BlockName << "'\n"; CurDAG->dump());
635 if (ViewLegalizeDAGs) CurDAG->viewGraph("legalize input for " + BlockName);
638 NamedRegionTimer T("DAG Legalization", GroupName, TimePassesIsEnabled);
642 DEBUG(dbgs() << "Legalized selection DAG: BB#" << BlockNumber
643 << " '" << BlockName << "'\n"; CurDAG->dump());
645 if (ViewDAGCombine2) CurDAG->viewGraph("dag-combine2 input for " + BlockName);
647 // Run the DAG combiner in post-legalize mode.
649 NamedRegionTimer T("DAG Combining 2", GroupName, TimePassesIsEnabled);
650 CurDAG->Combine(AfterLegalizeDAG, *AA, OptLevel);
653 DEBUG(dbgs() << "Optimized legalized selection DAG: BB#" << BlockNumber
654 << " '" << BlockName << "'\n"; CurDAG->dump());
656 if (OptLevel != CodeGenOpt::None)
657 ComputeLiveOutVRegInfo();
659 if (ViewISelDAGs) CurDAG->viewGraph("isel input for " + BlockName);
661 // Third, instruction select all of the operations to machine code, adding the
662 // code to the MachineBasicBlock.
664 NamedRegionTimer T("Instruction Selection", GroupName, TimePassesIsEnabled);
665 DoInstructionSelection();
668 DEBUG(dbgs() << "Selected selection DAG: BB#" << BlockNumber
669 << " '" << BlockName << "'\n"; CurDAG->dump());
671 if (ViewSchedDAGs) CurDAG->viewGraph("scheduler input for " + BlockName);
673 // Schedule machine code.
674 ScheduleDAGSDNodes *Scheduler = CreateScheduler();
676 NamedRegionTimer T("Instruction Scheduling", GroupName,
677 TimePassesIsEnabled);
678 Scheduler->Run(CurDAG, FuncInfo->MBB);
681 if (ViewSUnitDAGs) Scheduler->viewGraph();
683 // Emit machine code to BB. This can change 'BB' to the last block being
685 MachineBasicBlock *FirstMBB = FuncInfo->MBB, *LastMBB;
687 NamedRegionTimer T("Instruction Creation", GroupName, TimePassesIsEnabled);
689 // FuncInfo->InsertPt is passed by reference and set to the end of the
690 // scheduled instructions.
691 LastMBB = FuncInfo->MBB = Scheduler->EmitSchedule(FuncInfo->InsertPt);
694 // If the block was split, make sure we update any references that are used to
695 // update PHI nodes later on.
696 if (FirstMBB != LastMBB)
697 SDB->UpdateSplitBlock(FirstMBB, LastMBB);
699 // Free the scheduler state.
701 NamedRegionTimer T("Instruction Scheduling Cleanup", GroupName,
702 TimePassesIsEnabled);
706 // Free the SelectionDAG state, now that we're finished with it.
711 /// ISelUpdater - helper class to handle updates of the instruction selection
713 class ISelUpdater : public SelectionDAG::DAGUpdateListener {
714 SelectionDAG::allnodes_iterator &ISelPosition;
716 ISelUpdater(SelectionDAG &DAG, SelectionDAG::allnodes_iterator &isp)
717 : SelectionDAG::DAGUpdateListener(DAG), ISelPosition(isp) {}
719 /// NodeDeleted - Handle nodes deleted from the graph. If the node being
720 /// deleted is the current ISelPosition node, update ISelPosition.
722 virtual void NodeDeleted(SDNode *N, SDNode *E) {
723 if (ISelPosition == SelectionDAG::allnodes_iterator(N))
727 } // end anonymous namespace
729 void SelectionDAGISel::DoInstructionSelection() {
730 DEBUG(errs() << "===== Instruction selection begins: BB#"
731 << FuncInfo->MBB->getNumber()
732 << " '" << FuncInfo->MBB->getName() << "'\n");
736 // Select target instructions for the DAG.
738 // Number all nodes with a topological order and set DAGSize.
739 DAGSize = CurDAG->AssignTopologicalOrder();
741 // Create a dummy node (which is not added to allnodes), that adds
742 // a reference to the root node, preventing it from being deleted,
743 // and tracking any changes of the root.
744 HandleSDNode Dummy(CurDAG->getRoot());
745 SelectionDAG::allnodes_iterator ISelPosition (CurDAG->getRoot().getNode());
748 // Make sure that ISelPosition gets properly updated when nodes are deleted
749 // in calls made from this function.
750 ISelUpdater ISU(*CurDAG, ISelPosition);
752 // The AllNodes list is now topological-sorted. Visit the
753 // nodes by starting at the end of the list (the root of the
754 // graph) and preceding back toward the beginning (the entry
756 while (ISelPosition != CurDAG->allnodes_begin()) {
757 SDNode *Node = --ISelPosition;
758 // Skip dead nodes. DAGCombiner is expected to eliminate all dead nodes,
759 // but there are currently some corner cases that it misses. Also, this
760 // makes it theoretically possible to disable the DAGCombiner.
761 if (Node->use_empty())
764 SDNode *ResNode = Select(Node);
766 // FIXME: This is pretty gross. 'Select' should be changed to not return
767 // anything at all and this code should be nuked with a tactical strike.
769 // If node should not be replaced, continue with the next one.
770 if (ResNode == Node || Node->getOpcode() == ISD::DELETED_NODE)
774 ReplaceUses(Node, ResNode);
776 // If after the replacement this node is not used any more,
777 // remove this dead node.
778 if (Node->use_empty()) // Don't delete EntryToken, etc.
779 CurDAG->RemoveDeadNode(Node);
782 CurDAG->setRoot(Dummy.getValue());
785 DEBUG(errs() << "===== Instruction selection ends:\n");
787 PostprocessISelDAG();
790 /// PrepareEHLandingPad - Emit an EH_LABEL, set up live-in registers, and
791 /// do other setup for EH landing-pad blocks.
792 void SelectionDAGISel::PrepareEHLandingPad() {
793 MachineBasicBlock *MBB = FuncInfo->MBB;
795 // Add a label to mark the beginning of the landing pad. Deletion of the
796 // landing pad can thus be detected via the MachineModuleInfo.
797 MCSymbol *Label = MF->getMMI().addLandingPad(MBB);
799 // Assign the call site to the landing pad's begin label.
800 MF->getMMI().setCallSiteLandingPad(Label, SDB->LPadToCallSiteMap[MBB]);
802 const MCInstrDesc &II = TM.getInstrInfo()->get(TargetOpcode::EH_LABEL);
803 BuildMI(*MBB, FuncInfo->InsertPt, SDB->getCurDebugLoc(), II)
806 // Mark exception register as live in.
807 unsigned Reg = TLI.getExceptionPointerRegister();
808 if (Reg) MBB->addLiveIn(Reg);
810 // Mark exception selector register as live in.
811 Reg = TLI.getExceptionSelectorRegister();
812 if (Reg) MBB->addLiveIn(Reg);
815 /// TryToFoldFastISelLoad - We're checking to see if we can fold the specified
816 /// load into the specified FoldInst. Note that we could have a sequence where
817 /// multiple LLVM IR instructions are folded into the same machineinstr. For
818 /// example we could have:
819 /// A: x = load i32 *P
820 /// B: y = icmp A, 42
823 /// In this scenario, LI is "A", and FoldInst is "C". We know about "B" (and
824 /// any other folded instructions) because it is between A and C.
826 /// If we succeed in folding the load into the operation, return true.
828 bool SelectionDAGISel::TryToFoldFastISelLoad(const LoadInst *LI,
829 const Instruction *FoldInst,
831 // We know that the load has a single use, but don't know what it is. If it
832 // isn't one of the folded instructions, then we can't succeed here. Handle
833 // this by scanning the single-use users of the load until we get to FoldInst.
834 unsigned MaxUsers = 6; // Don't scan down huge single-use chains of instrs.
836 const Instruction *TheUser = LI->use_back();
837 while (TheUser != FoldInst && // Scan up until we find FoldInst.
838 // Stay in the right block.
839 TheUser->getParent() == FoldInst->getParent() &&
840 --MaxUsers) { // Don't scan too far.
841 // If there are multiple or no uses of this instruction, then bail out.
842 if (!TheUser->hasOneUse())
845 TheUser = TheUser->use_back();
848 // If we didn't find the fold instruction, then we failed to collapse the
850 if (TheUser != FoldInst)
853 // Don't try to fold volatile loads. Target has to deal with alignment
855 if (LI->isVolatile()) return false;
857 // Figure out which vreg this is going into. If there is no assigned vreg yet
858 // then there actually was no reference to it. Perhaps the load is referenced
859 // by a dead instruction.
860 unsigned LoadReg = FastIS->getRegForValue(LI);
864 // Check to see what the uses of this vreg are. If it has no uses, or more
865 // than one use (at the machine instr level) then we can't fold it.
866 MachineRegisterInfo::reg_iterator RI = RegInfo->reg_begin(LoadReg);
867 if (RI == RegInfo->reg_end())
870 // See if there is exactly one use of the vreg. If there are multiple uses,
871 // then the instruction got lowered to multiple machine instructions or the
872 // use of the loaded value ended up being multiple operands of the result, in
873 // either case, we can't fold this.
874 MachineRegisterInfo::reg_iterator PostRI = RI; ++PostRI;
875 if (PostRI != RegInfo->reg_end())
878 assert(RI.getOperand().isUse() &&
879 "The only use of the vreg must be a use, we haven't emitted the def!");
881 MachineInstr *User = &*RI;
883 // Set the insertion point properly. Folding the load can cause generation of
884 // other random instructions (like sign extends) for addressing modes, make
885 // sure they get inserted in a logical place before the new instruction.
886 FuncInfo->InsertPt = User;
887 FuncInfo->MBB = User->getParent();
889 // Ask the target to try folding the load.
890 return FastIS->TryToFoldLoad(User, RI.getOperandNo(), LI);
893 /// isFoldedOrDeadInstruction - Return true if the specified instruction is
894 /// side-effect free and is either dead or folded into a generated instruction.
895 /// Return false if it needs to be emitted.
896 static bool isFoldedOrDeadInstruction(const Instruction *I,
897 FunctionLoweringInfo *FuncInfo) {
898 return !I->mayWriteToMemory() && // Side-effecting instructions aren't folded.
899 !isa<TerminatorInst>(I) && // Terminators aren't folded.
900 !isa<DbgInfoIntrinsic>(I) && // Debug instructions aren't folded.
901 !isa<LandingPadInst>(I) && // Landingpad instructions aren't folded.
902 !FuncInfo->isExportedInst(I); // Exported instrs must be computed.
906 // Collect per Instruction statistics for fast-isel misses. Only those
907 // instructions that cause the bail are accounted for. It does not account for
908 // instructions higher in the block. Thus, summing the per instructions stats
909 // will not add up to what is reported by NumFastIselFailures.
910 static void collectFailStats(const Instruction *I) {
911 switch (I->getOpcode()) {
912 default: assert (0 && "<Invalid operator> ");
915 case Instruction::Ret: NumFastIselFailRet++; return;
916 case Instruction::Br: NumFastIselFailBr++; return;
917 case Instruction::Switch: NumFastIselFailSwitch++; return;
918 case Instruction::IndirectBr: NumFastIselFailIndirectBr++; return;
919 case Instruction::Invoke: NumFastIselFailInvoke++; return;
920 case Instruction::Resume: NumFastIselFailResume++; return;
921 case Instruction::Unreachable: NumFastIselFailUnreachable++; return;
923 // Standard binary operators...
924 case Instruction::Add: NumFastIselFailAdd++; return;
925 case Instruction::FAdd: NumFastIselFailFAdd++; return;
926 case Instruction::Sub: NumFastIselFailSub++; return;
927 case Instruction::FSub: NumFastIselFailFSub++; return;
928 case Instruction::Mul: NumFastIselFailMul++; return;
929 case Instruction::FMul: NumFastIselFailFMul++; return;
930 case Instruction::UDiv: NumFastIselFailUDiv++; return;
931 case Instruction::SDiv: NumFastIselFailSDiv++; return;
932 case Instruction::FDiv: NumFastIselFailFDiv++; return;
933 case Instruction::URem: NumFastIselFailURem++; return;
934 case Instruction::SRem: NumFastIselFailSRem++; return;
935 case Instruction::FRem: NumFastIselFailFRem++; return;
937 // Logical operators...
938 case Instruction::And: NumFastIselFailAnd++; return;
939 case Instruction::Or: NumFastIselFailOr++; return;
940 case Instruction::Xor: NumFastIselFailXor++; return;
942 // Memory instructions...
943 case Instruction::Alloca: NumFastIselFailAlloca++; return;
944 case Instruction::Load: NumFastIselFailLoad++; return;
945 case Instruction::Store: NumFastIselFailStore++; return;
946 case Instruction::AtomicCmpXchg: NumFastIselFailAtomicCmpXchg++; return;
947 case Instruction::AtomicRMW: NumFastIselFailAtomicRMW++; return;
948 case Instruction::Fence: NumFastIselFailFence++; return;
949 case Instruction::GetElementPtr: NumFastIselFailGetElementPtr++; return;
951 // Convert instructions...
952 case Instruction::Trunc: NumFastIselFailTrunc++; return;
953 case Instruction::ZExt: NumFastIselFailZExt++; return;
954 case Instruction::SExt: NumFastIselFailSExt++; return;
955 case Instruction::FPTrunc: NumFastIselFailFPTrunc++; return;
956 case Instruction::FPExt: NumFastIselFailFPExt++; return;
957 case Instruction::FPToUI: NumFastIselFailFPToUI++; return;
958 case Instruction::FPToSI: NumFastIselFailFPToSI++; return;
959 case Instruction::UIToFP: NumFastIselFailUIToFP++; return;
960 case Instruction::SIToFP: NumFastIselFailSIToFP++; return;
961 case Instruction::IntToPtr: NumFastIselFailIntToPtr++; return;
962 case Instruction::PtrToInt: NumFastIselFailPtrToInt++; return;
963 case Instruction::BitCast: NumFastIselFailBitCast++; return;
965 // Other instructions...
966 case Instruction::ICmp: NumFastIselFailICmp++; return;
967 case Instruction::FCmp: NumFastIselFailFCmp++; return;
968 case Instruction::PHI: NumFastIselFailPHI++; return;
969 case Instruction::Select: NumFastIselFailSelect++; return;
970 case Instruction::Call: NumFastIselFailCall++; return;
971 case Instruction::Shl: NumFastIselFailShl++; return;
972 case Instruction::LShr: NumFastIselFailLShr++; return;
973 case Instruction::AShr: NumFastIselFailAShr++; return;
974 case Instruction::VAArg: NumFastIselFailVAArg++; return;
975 case Instruction::ExtractElement: NumFastIselFailExtractElement++; return;
976 case Instruction::InsertElement: NumFastIselFailInsertElement++; return;
977 case Instruction::ShuffleVector: NumFastIselFailShuffleVector++; return;
978 case Instruction::ExtractValue: NumFastIselFailExtractValue++; return;
979 case Instruction::InsertValue: NumFastIselFailInsertValue++; return;
980 case Instruction::LandingPad: NumFastIselFailLandingPad++; return;
985 void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
986 // Initialize the Fast-ISel state, if needed.
987 FastISel *FastIS = 0;
988 if (TM.Options.EnableFastISel)
989 FastIS = TLI.createFastISel(*FuncInfo, LibInfo);
991 // Iterate over all basic blocks in the function.
992 ReversePostOrderTraversal<const Function*> RPOT(&Fn);
993 for (ReversePostOrderTraversal<const Function*>::rpo_iterator
994 I = RPOT.begin(), E = RPOT.end(); I != E; ++I) {
995 const BasicBlock *LLVMBB = *I;
997 if (OptLevel != CodeGenOpt::None) {
998 bool AllPredsVisited = true;
999 for (const_pred_iterator PI = pred_begin(LLVMBB), PE = pred_end(LLVMBB);
1001 if (!FuncInfo->VisitedBBs.count(*PI)) {
1002 AllPredsVisited = false;
1007 if (AllPredsVisited) {
1008 for (BasicBlock::const_iterator I = LLVMBB->begin();
1009 isa<PHINode>(I); ++I)
1010 FuncInfo->ComputePHILiveOutRegInfo(cast<PHINode>(I));
1012 for (BasicBlock::const_iterator I = LLVMBB->begin();
1013 isa<PHINode>(I); ++I)
1014 FuncInfo->InvalidatePHILiveOutRegInfo(cast<PHINode>(I));
1017 FuncInfo->VisitedBBs.insert(LLVMBB);
1020 FuncInfo->MBB = FuncInfo->MBBMap[LLVMBB];
1021 FuncInfo->InsertPt = FuncInfo->MBB->getFirstNonPHI();
1023 BasicBlock::const_iterator const Begin = LLVMBB->getFirstNonPHI();
1024 BasicBlock::const_iterator const End = LLVMBB->end();
1025 BasicBlock::const_iterator BI = End;
1027 FuncInfo->InsertPt = FuncInfo->MBB->getFirstNonPHI();
1029 // Setup an EH landing-pad block.
1030 if (FuncInfo->MBB->isLandingPad())
1031 PrepareEHLandingPad();
1033 // Lower any arguments needed in this block if this is the entry block.
1034 if (LLVMBB == &Fn.getEntryBlock())
1035 LowerArguments(LLVMBB);
1037 // Before doing SelectionDAG ISel, see if FastISel has been requested.
1039 FastIS->startNewBlock();
1041 // Emit code for any incoming arguments. This must happen before
1042 // beginning FastISel on the entry block.
1043 if (LLVMBB == &Fn.getEntryBlock()) {
1044 CurDAG->setRoot(SDB->getControlRoot());
1046 CodeGenAndEmitDAG();
1048 // If we inserted any instructions at the beginning, make a note of
1049 // where they are, so we can be sure to emit subsequent instructions
1051 if (FuncInfo->InsertPt != FuncInfo->MBB->begin())
1052 FastIS->setLastLocalValue(llvm::prior(FuncInfo->InsertPt));
1054 FastIS->setLastLocalValue(0);
1057 unsigned NumFastIselRemaining = std::distance(Begin, End);
1058 // Do FastISel on as many instructions as possible.
1059 for (; BI != Begin; --BI) {
1060 const Instruction *Inst = llvm::prior(BI);
1062 // If we no longer require this instruction, skip it.
1063 if (isFoldedOrDeadInstruction(Inst, FuncInfo)) {
1064 --NumFastIselRemaining;
1068 // Bottom-up: reset the insert pos at the top, after any local-value
1070 FastIS->recomputeInsertPt();
1072 // Try to select the instruction with FastISel.
1073 if (FastIS->SelectInstruction(Inst)) {
1074 --NumFastIselRemaining;
1075 ++NumFastIselSuccess;
1076 // If fast isel succeeded, skip over all the folded instructions, and
1077 // then see if there is a load right before the selected instructions.
1078 // Try to fold the load if so.
1079 const Instruction *BeforeInst = Inst;
1080 while (BeforeInst != Begin) {
1081 BeforeInst = llvm::prior(BasicBlock::const_iterator(BeforeInst));
1082 if (!isFoldedOrDeadInstruction(BeforeInst, FuncInfo))
1085 if (BeforeInst != Inst && isa<LoadInst>(BeforeInst) &&
1086 BeforeInst->hasOneUse() &&
1087 TryToFoldFastISelLoad(cast<LoadInst>(BeforeInst), Inst, FastIS)) {
1088 // If we succeeded, don't re-select the load.
1089 BI = llvm::next(BasicBlock::const_iterator(BeforeInst));
1090 --NumFastIselRemaining;
1091 ++NumFastIselSuccess;
1097 if (EnableFastISelVerbose2)
1098 collectFailStats(Inst);
1101 // Then handle certain instructions as single-LLVM-Instruction blocks.
1102 if (isa<CallInst>(Inst)) {
1104 if (EnableFastISelVerbose || EnableFastISelAbort) {
1105 dbgs() << "FastISel missed call: ";
1109 if (!Inst->getType()->isVoidTy() && !Inst->use_empty()) {
1110 unsigned &R = FuncInfo->ValueMap[Inst];
1112 R = FuncInfo->CreateRegs(Inst->getType());
1115 bool HadTailCall = false;
1116 SelectBasicBlock(Inst, BI, HadTailCall);
1118 // Recompute NumFastIselRemaining as Selection DAG instruction
1119 // selection may have handled the call, input args, etc.
1120 unsigned RemainingNow = std::distance(Begin, BI);
1121 NumFastIselFailures += NumFastIselRemaining - RemainingNow;
1123 // If the call was emitted as a tail call, we're done with the block.
1129 NumFastIselRemaining = RemainingNow;
1133 if (isa<TerminatorInst>(Inst) && !isa<BranchInst>(Inst)) {
1134 // Don't abort, and use a different message for terminator misses.
1135 NumFastIselFailures += NumFastIselRemaining;
1136 if (EnableFastISelVerbose || EnableFastISelAbort) {
1137 dbgs() << "FastISel missed terminator: ";
1141 NumFastIselFailures += NumFastIselRemaining;
1142 if (EnableFastISelVerbose || EnableFastISelAbort) {
1143 dbgs() << "FastISel miss: ";
1146 if (EnableFastISelAbort)
1147 // The "fast" selector couldn't handle something and bailed.
1148 // For the purpose of debugging, just abort.
1149 llvm_unreachable("FastISel didn't select the entire block");
1154 FastIS->recomputeInsertPt();
1160 ++NumFastIselBlocks;
1163 // Run SelectionDAG instruction selection on the remainder of the block
1164 // not handled by FastISel. If FastISel is not run, this is the entire
1167 SelectBasicBlock(Begin, BI, HadTailCall);
1171 FuncInfo->PHINodesToUpdate.clear();
1175 SDB->clearDanglingDebugInfo();
1179 SelectionDAGISel::FinishBasicBlock() {
1181 DEBUG(dbgs() << "Total amount of phi nodes to update: "
1182 << FuncInfo->PHINodesToUpdate.size() << "\n";
1183 for (unsigned i = 0, e = FuncInfo->PHINodesToUpdate.size(); i != e; ++i)
1184 dbgs() << "Node " << i << " : ("
1185 << FuncInfo->PHINodesToUpdate[i].first
1186 << ", " << FuncInfo->PHINodesToUpdate[i].second << ")\n");
1188 // Next, now that we know what the last MBB the LLVM BB expanded is, update
1189 // PHI nodes in successors.
1190 if (SDB->SwitchCases.empty() &&
1191 SDB->JTCases.empty() &&
1192 SDB->BitTestCases.empty()) {
1193 for (unsigned i = 0, e = FuncInfo->PHINodesToUpdate.size(); i != e; ++i) {
1194 MachineInstr *PHI = FuncInfo->PHINodesToUpdate[i].first;
1195 assert(PHI->isPHI() &&
1196 "This is not a machine PHI node that we are updating!");
1197 if (!FuncInfo->MBB->isSuccessor(PHI->getParent()))
1200 MachineOperand::CreateReg(FuncInfo->PHINodesToUpdate[i].second, false));
1201 PHI->addOperand(MachineOperand::CreateMBB(FuncInfo->MBB));
1206 for (unsigned i = 0, e = SDB->BitTestCases.size(); i != e; ++i) {
1207 // Lower header first, if it wasn't already lowered
1208 if (!SDB->BitTestCases[i].Emitted) {
1209 // Set the current basic block to the mbb we wish to insert the code into
1210 FuncInfo->MBB = SDB->BitTestCases[i].Parent;
1211 FuncInfo->InsertPt = FuncInfo->MBB->end();
1213 SDB->visitBitTestHeader(SDB->BitTestCases[i], FuncInfo->MBB);
1214 CurDAG->setRoot(SDB->getRoot());
1216 CodeGenAndEmitDAG();
1219 uint32_t UnhandledWeight = 0;
1220 for (unsigned j = 0, ej = SDB->BitTestCases[i].Cases.size(); j != ej; ++j)
1221 UnhandledWeight += SDB->BitTestCases[i].Cases[j].ExtraWeight;
1223 for (unsigned j = 0, ej = SDB->BitTestCases[i].Cases.size(); j != ej; ++j) {
1224 UnhandledWeight -= SDB->BitTestCases[i].Cases[j].ExtraWeight;
1225 // Set the current basic block to the mbb we wish to insert the code into
1226 FuncInfo->MBB = SDB->BitTestCases[i].Cases[j].ThisBB;
1227 FuncInfo->InsertPt = FuncInfo->MBB->end();
1230 SDB->visitBitTestCase(SDB->BitTestCases[i],
1231 SDB->BitTestCases[i].Cases[j+1].ThisBB,
1233 SDB->BitTestCases[i].Reg,
1234 SDB->BitTestCases[i].Cases[j],
1237 SDB->visitBitTestCase(SDB->BitTestCases[i],
1238 SDB->BitTestCases[i].Default,
1240 SDB->BitTestCases[i].Reg,
1241 SDB->BitTestCases[i].Cases[j],
1245 CurDAG->setRoot(SDB->getRoot());
1247 CodeGenAndEmitDAG();
1251 for (unsigned pi = 0, pe = FuncInfo->PHINodesToUpdate.size();
1253 MachineInstr *PHI = FuncInfo->PHINodesToUpdate[pi].first;
1254 MachineBasicBlock *PHIBB = PHI->getParent();
1255 assert(PHI->isPHI() &&
1256 "This is not a machine PHI node that we are updating!");
1257 // This is "default" BB. We have two jumps to it. From "header" BB and
1258 // from last "case" BB.
1259 if (PHIBB == SDB->BitTestCases[i].Default) {
1260 PHI->addOperand(MachineOperand::
1261 CreateReg(FuncInfo->PHINodesToUpdate[pi].second,
1263 PHI->addOperand(MachineOperand::CreateMBB(SDB->BitTestCases[i].Parent));
1264 PHI->addOperand(MachineOperand::
1265 CreateReg(FuncInfo->PHINodesToUpdate[pi].second,
1267 PHI->addOperand(MachineOperand::CreateMBB(SDB->BitTestCases[i].Cases.
1270 // One of "cases" BB.
1271 for (unsigned j = 0, ej = SDB->BitTestCases[i].Cases.size();
1273 MachineBasicBlock* cBB = SDB->BitTestCases[i].Cases[j].ThisBB;
1274 if (cBB->isSuccessor(PHIBB)) {
1275 PHI->addOperand(MachineOperand::
1276 CreateReg(FuncInfo->PHINodesToUpdate[pi].second,
1278 PHI->addOperand(MachineOperand::CreateMBB(cBB));
1283 SDB->BitTestCases.clear();
1285 // If the JumpTable record is filled in, then we need to emit a jump table.
1286 // Updating the PHI nodes is tricky in this case, since we need to determine
1287 // whether the PHI is a successor of the range check MBB or the jump table MBB
1288 for (unsigned i = 0, e = SDB->JTCases.size(); i != e; ++i) {
1289 // Lower header first, if it wasn't already lowered
1290 if (!SDB->JTCases[i].first.Emitted) {
1291 // Set the current basic block to the mbb we wish to insert the code into
1292 FuncInfo->MBB = SDB->JTCases[i].first.HeaderBB;
1293 FuncInfo->InsertPt = FuncInfo->MBB->end();
1295 SDB->visitJumpTableHeader(SDB->JTCases[i].second, SDB->JTCases[i].first,
1297 CurDAG->setRoot(SDB->getRoot());
1299 CodeGenAndEmitDAG();
1302 // Set the current basic block to the mbb we wish to insert the code into
1303 FuncInfo->MBB = SDB->JTCases[i].second.MBB;
1304 FuncInfo->InsertPt = FuncInfo->MBB->end();
1306 SDB->visitJumpTable(SDB->JTCases[i].second);
1307 CurDAG->setRoot(SDB->getRoot());
1309 CodeGenAndEmitDAG();
1312 for (unsigned pi = 0, pe = FuncInfo->PHINodesToUpdate.size();
1314 MachineInstr *PHI = FuncInfo->PHINodesToUpdate[pi].first;
1315 MachineBasicBlock *PHIBB = PHI->getParent();
1316 assert(PHI->isPHI() &&
1317 "This is not a machine PHI node that we are updating!");
1318 // "default" BB. We can go there only from header BB.
1319 if (PHIBB == SDB->JTCases[i].second.Default) {
1321 (MachineOperand::CreateReg(FuncInfo->PHINodesToUpdate[pi].second,
1324 (MachineOperand::CreateMBB(SDB->JTCases[i].first.HeaderBB));
1326 // JT BB. Just iterate over successors here
1327 if (FuncInfo->MBB->isSuccessor(PHIBB)) {
1329 (MachineOperand::CreateReg(FuncInfo->PHINodesToUpdate[pi].second,
1331 PHI->addOperand(MachineOperand::CreateMBB(FuncInfo->MBB));
1335 SDB->JTCases.clear();
1337 // If the switch block involved a branch to one of the actual successors, we
1338 // need to update PHI nodes in that block.
1339 for (unsigned i = 0, e = FuncInfo->PHINodesToUpdate.size(); i != e; ++i) {
1340 MachineInstr *PHI = FuncInfo->PHINodesToUpdate[i].first;
1341 assert(PHI->isPHI() &&
1342 "This is not a machine PHI node that we are updating!");
1343 if (FuncInfo->MBB->isSuccessor(PHI->getParent())) {
1345 MachineOperand::CreateReg(FuncInfo->PHINodesToUpdate[i].second, false));
1346 PHI->addOperand(MachineOperand::CreateMBB(FuncInfo->MBB));
1350 // If we generated any switch lowering information, build and codegen any
1351 // additional DAGs necessary.
1352 for (unsigned i = 0, e = SDB->SwitchCases.size(); i != e; ++i) {
1353 // Set the current basic block to the mbb we wish to insert the code into
1354 FuncInfo->MBB = SDB->SwitchCases[i].ThisBB;
1355 FuncInfo->InsertPt = FuncInfo->MBB->end();
1357 // Determine the unique successors.
1358 SmallVector<MachineBasicBlock *, 2> Succs;
1359 Succs.push_back(SDB->SwitchCases[i].TrueBB);
1360 if (SDB->SwitchCases[i].TrueBB != SDB->SwitchCases[i].FalseBB)
1361 Succs.push_back(SDB->SwitchCases[i].FalseBB);
1363 // Emit the code. Note that this could result in FuncInfo->MBB being split.
1364 SDB->visitSwitchCase(SDB->SwitchCases[i], FuncInfo->MBB);
1365 CurDAG->setRoot(SDB->getRoot());
1367 CodeGenAndEmitDAG();
1369 // Remember the last block, now that any splitting is done, for use in
1370 // populating PHI nodes in successors.
1371 MachineBasicBlock *ThisBB = FuncInfo->MBB;
1373 // Handle any PHI nodes in successors of this chunk, as if we were coming
1374 // from the original BB before switch expansion. Note that PHI nodes can
1375 // occur multiple times in PHINodesToUpdate. We have to be very careful to
1376 // handle them the right number of times.
1377 for (unsigned i = 0, e = Succs.size(); i != e; ++i) {
1378 FuncInfo->MBB = Succs[i];
1379 FuncInfo->InsertPt = FuncInfo->MBB->end();
1380 // FuncInfo->MBB may have been removed from the CFG if a branch was
1382 if (ThisBB->isSuccessor(FuncInfo->MBB)) {
1383 for (MachineBasicBlock::iterator Phi = FuncInfo->MBB->begin();
1384 Phi != FuncInfo->MBB->end() && Phi->isPHI();
1386 // This value for this PHI node is recorded in PHINodesToUpdate.
1387 for (unsigned pn = 0; ; ++pn) {
1388 assert(pn != FuncInfo->PHINodesToUpdate.size() &&
1389 "Didn't find PHI entry!");
1390 if (FuncInfo->PHINodesToUpdate[pn].first == Phi) {
1391 Phi->addOperand(MachineOperand::
1392 CreateReg(FuncInfo->PHINodesToUpdate[pn].second,
1394 Phi->addOperand(MachineOperand::CreateMBB(ThisBB));
1402 SDB->SwitchCases.clear();
1406 /// Create the scheduler. If a specific scheduler was specified
1407 /// via the SchedulerRegistry, use it, otherwise select the
1408 /// one preferred by the target.
1410 ScheduleDAGSDNodes *SelectionDAGISel::CreateScheduler() {
1411 RegisterScheduler::FunctionPassCtor Ctor = RegisterScheduler::getDefault();
1415 RegisterScheduler::setDefault(Ctor);
1418 return Ctor(this, OptLevel);
1421 //===----------------------------------------------------------------------===//
1422 // Helper functions used by the generated instruction selector.
1423 //===----------------------------------------------------------------------===//
1424 // Calls to these methods are generated by tblgen.
1426 /// CheckAndMask - The isel is trying to match something like (and X, 255). If
1427 /// the dag combiner simplified the 255, we still want to match. RHS is the
1428 /// actual value in the DAG on the RHS of an AND, and DesiredMaskS is the value
1429 /// specified in the .td file (e.g. 255).
1430 bool SelectionDAGISel::CheckAndMask(SDValue LHS, ConstantSDNode *RHS,
1431 int64_t DesiredMaskS) const {
1432 const APInt &ActualMask = RHS->getAPIntValue();
1433 const APInt &DesiredMask = APInt(LHS.getValueSizeInBits(), DesiredMaskS);
1435 // If the actual mask exactly matches, success!
1436 if (ActualMask == DesiredMask)
1439 // If the actual AND mask is allowing unallowed bits, this doesn't match.
1440 if (ActualMask.intersects(~DesiredMask))
1443 // Otherwise, the DAG Combiner may have proven that the value coming in is
1444 // either already zero or is not demanded. Check for known zero input bits.
1445 APInt NeededMask = DesiredMask & ~ActualMask;
1446 if (CurDAG->MaskedValueIsZero(LHS, NeededMask))
1449 // TODO: check to see if missing bits are just not demanded.
1451 // Otherwise, this pattern doesn't match.
1455 /// CheckOrMask - The isel is trying to match something like (or X, 255). If
1456 /// the dag combiner simplified the 255, we still want to match. RHS is the
1457 /// actual value in the DAG on the RHS of an OR, and DesiredMaskS is the value
1458 /// specified in the .td file (e.g. 255).
1459 bool SelectionDAGISel::CheckOrMask(SDValue LHS, ConstantSDNode *RHS,
1460 int64_t DesiredMaskS) const {
1461 const APInt &ActualMask = RHS->getAPIntValue();
1462 const APInt &DesiredMask = APInt(LHS.getValueSizeInBits(), DesiredMaskS);
1464 // If the actual mask exactly matches, success!
1465 if (ActualMask == DesiredMask)
1468 // If the actual AND mask is allowing unallowed bits, this doesn't match.
1469 if (ActualMask.intersects(~DesiredMask))
1472 // Otherwise, the DAG Combiner may have proven that the value coming in is
1473 // either already zero or is not demanded. Check for known zero input bits.
1474 APInt NeededMask = DesiredMask & ~ActualMask;
1476 APInt KnownZero, KnownOne;
1477 CurDAG->ComputeMaskedBits(LHS, KnownZero, KnownOne);
1479 // If all the missing bits in the or are already known to be set, match!
1480 if ((NeededMask & KnownOne) == NeededMask)
1483 // TODO: check to see if missing bits are just not demanded.
1485 // Otherwise, this pattern doesn't match.
1490 /// SelectInlineAsmMemoryOperands - Calls to this are automatically generated
1491 /// by tblgen. Others should not call it.
1492 void SelectionDAGISel::
1493 SelectInlineAsmMemoryOperands(std::vector<SDValue> &Ops) {
1494 std::vector<SDValue> InOps;
1495 std::swap(InOps, Ops);
1497 Ops.push_back(InOps[InlineAsm::Op_InputChain]); // 0
1498 Ops.push_back(InOps[InlineAsm::Op_AsmString]); // 1
1499 Ops.push_back(InOps[InlineAsm::Op_MDNode]); // 2, !srcloc
1500 Ops.push_back(InOps[InlineAsm::Op_ExtraInfo]); // 3 (SideEffect, AlignStack)
1502 unsigned i = InlineAsm::Op_FirstOperand, e = InOps.size();
1503 if (InOps[e-1].getValueType() == MVT::Glue)
1504 --e; // Don't process a glue operand if it is here.
1507 unsigned Flags = cast<ConstantSDNode>(InOps[i])->getZExtValue();
1508 if (!InlineAsm::isMemKind(Flags)) {
1509 // Just skip over this operand, copying the operands verbatim.
1510 Ops.insert(Ops.end(), InOps.begin()+i,
1511 InOps.begin()+i+InlineAsm::getNumOperandRegisters(Flags) + 1);
1512 i += InlineAsm::getNumOperandRegisters(Flags) + 1;
1514 assert(InlineAsm::getNumOperandRegisters(Flags) == 1 &&
1515 "Memory operand with multiple values?");
1516 // Otherwise, this is a memory operand. Ask the target to select it.
1517 std::vector<SDValue> SelOps;
1518 if (SelectInlineAsmMemoryOperand(InOps[i+1], 'm', SelOps))
1519 report_fatal_error("Could not match memory address. Inline asm"
1522 // Add this to the output node.
1524 InlineAsm::getFlagWord(InlineAsm::Kind_Mem, SelOps.size());
1525 Ops.push_back(CurDAG->getTargetConstant(NewFlags, MVT::i32));
1526 Ops.insert(Ops.end(), SelOps.begin(), SelOps.end());
1531 // Add the glue input back if present.
1532 if (e != InOps.size())
1533 Ops.push_back(InOps.back());
1536 /// findGlueUse - Return use of MVT::Glue value produced by the specified
1539 static SDNode *findGlueUse(SDNode *N) {
1540 unsigned FlagResNo = N->getNumValues()-1;
1541 for (SDNode::use_iterator I = N->use_begin(), E = N->use_end(); I != E; ++I) {
1542 SDUse &Use = I.getUse();
1543 if (Use.getResNo() == FlagResNo)
1544 return Use.getUser();
1549 /// findNonImmUse - Return true if "Use" is a non-immediate use of "Def".
1550 /// This function recursively traverses up the operand chain, ignoring
1552 static bool findNonImmUse(SDNode *Use, SDNode* Def, SDNode *ImmedUse,
1553 SDNode *Root, SmallPtrSet<SDNode*, 16> &Visited,
1554 bool IgnoreChains) {
1555 // The NodeID's are given uniques ID's where a node ID is guaranteed to be
1556 // greater than all of its (recursive) operands. If we scan to a point where
1557 // 'use' is smaller than the node we're scanning for, then we know we will
1560 // The Use may be -1 (unassigned) if it is a newly allocated node. This can
1561 // happen because we scan down to newly selected nodes in the case of glue
1563 if ((Use->getNodeId() < Def->getNodeId() && Use->getNodeId() != -1))
1566 // Don't revisit nodes if we already scanned it and didn't fail, we know we
1567 // won't fail if we scan it again.
1568 if (!Visited.insert(Use))
1571 for (unsigned i = 0, e = Use->getNumOperands(); i != e; ++i) {
1572 // Ignore chain uses, they are validated by HandleMergeInputChains.
1573 if (Use->getOperand(i).getValueType() == MVT::Other && IgnoreChains)
1576 SDNode *N = Use->getOperand(i).getNode();
1578 if (Use == ImmedUse || Use == Root)
1579 continue; // We are not looking for immediate use.
1584 // Traverse up the operand chain.
1585 if (findNonImmUse(N, Def, ImmedUse, Root, Visited, IgnoreChains))
1591 /// IsProfitableToFold - Returns true if it's profitable to fold the specific
1592 /// operand node N of U during instruction selection that starts at Root.
1593 bool SelectionDAGISel::IsProfitableToFold(SDValue N, SDNode *U,
1594 SDNode *Root) const {
1595 if (OptLevel == CodeGenOpt::None) return false;
1596 return N.hasOneUse();
1599 /// IsLegalToFold - Returns true if the specific operand node N of
1600 /// U can be folded during instruction selection that starts at Root.
1601 bool SelectionDAGISel::IsLegalToFold(SDValue N, SDNode *U, SDNode *Root,
1602 CodeGenOpt::Level OptLevel,
1603 bool IgnoreChains) {
1604 if (OptLevel == CodeGenOpt::None) return false;
1606 // If Root use can somehow reach N through a path that that doesn't contain
1607 // U then folding N would create a cycle. e.g. In the following
1608 // diagram, Root can reach N through X. If N is folded into into Root, then
1609 // X is both a predecessor and a successor of U.
1620 // * indicates nodes to be folded together.
1622 // If Root produces glue, then it gets (even more) interesting. Since it
1623 // will be "glued" together with its glue use in the scheduler, we need to
1624 // check if it might reach N.
1643 // If GU (glue use) indirectly reaches N (the load), and Root folds N
1644 // (call it Fold), then X is a predecessor of GU and a successor of
1645 // Fold. But since Fold and GU are glued together, this will create
1646 // a cycle in the scheduling graph.
1648 // If the node has glue, walk down the graph to the "lowest" node in the
1650 EVT VT = Root->getValueType(Root->getNumValues()-1);
1651 while (VT == MVT::Glue) {
1652 SDNode *GU = findGlueUse(Root);
1656 VT = Root->getValueType(Root->getNumValues()-1);
1658 // If our query node has a glue result with a use, we've walked up it. If
1659 // the user (which has already been selected) has a chain or indirectly uses
1660 // the chain, our WalkChainUsers predicate will not consider it. Because of
1661 // this, we cannot ignore chains in this predicate.
1662 IgnoreChains = false;
1666 SmallPtrSet<SDNode*, 16> Visited;
1667 return !findNonImmUse(Root, N.getNode(), U, Root, Visited, IgnoreChains);
1670 SDNode *SelectionDAGISel::Select_INLINEASM(SDNode *N) {
1671 std::vector<SDValue> Ops(N->op_begin(), N->op_end());
1672 SelectInlineAsmMemoryOperands(Ops);
1674 std::vector<EVT> VTs;
1675 VTs.push_back(MVT::Other);
1676 VTs.push_back(MVT::Glue);
1677 SDValue New = CurDAG->getNode(ISD::INLINEASM, N->getDebugLoc(),
1678 VTs, &Ops[0], Ops.size());
1680 return New.getNode();
1683 SDNode *SelectionDAGISel::Select_UNDEF(SDNode *N) {
1684 return CurDAG->SelectNodeTo(N, TargetOpcode::IMPLICIT_DEF,N->getValueType(0));
1687 /// GetVBR - decode a vbr encoding whose top bit is set.
1688 LLVM_ATTRIBUTE_ALWAYS_INLINE static uint64_t
1689 GetVBR(uint64_t Val, const unsigned char *MatcherTable, unsigned &Idx) {
1690 assert(Val >= 128 && "Not a VBR");
1691 Val &= 127; // Remove first vbr bit.
1696 NextBits = MatcherTable[Idx++];
1697 Val |= (NextBits&127) << Shift;
1699 } while (NextBits & 128);
1705 /// UpdateChainsAndGlue - When a match is complete, this method updates uses of
1706 /// interior glue and chain results to use the new glue and chain results.
1707 void SelectionDAGISel::
1708 UpdateChainsAndGlue(SDNode *NodeToMatch, SDValue InputChain,
1709 const SmallVectorImpl<SDNode*> &ChainNodesMatched,
1711 const SmallVectorImpl<SDNode*> &GlueResultNodesMatched,
1712 bool isMorphNodeTo) {
1713 SmallVector<SDNode*, 4> NowDeadNodes;
1715 // Now that all the normal results are replaced, we replace the chain and
1716 // glue results if present.
1717 if (!ChainNodesMatched.empty()) {
1718 assert(InputChain.getNode() != 0 &&
1719 "Matched input chains but didn't produce a chain");
1720 // Loop over all of the nodes we matched that produced a chain result.
1721 // Replace all the chain results with the final chain we ended up with.
1722 for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) {
1723 SDNode *ChainNode = ChainNodesMatched[i];
1725 // If this node was already deleted, don't look at it.
1726 if (ChainNode->getOpcode() == ISD::DELETED_NODE)
1729 // Don't replace the results of the root node if we're doing a
1731 if (ChainNode == NodeToMatch && isMorphNodeTo)
1734 SDValue ChainVal = SDValue(ChainNode, ChainNode->getNumValues()-1);
1735 if (ChainVal.getValueType() == MVT::Glue)
1736 ChainVal = ChainVal.getValue(ChainVal->getNumValues()-2);
1737 assert(ChainVal.getValueType() == MVT::Other && "Not a chain?");
1738 CurDAG->ReplaceAllUsesOfValueWith(ChainVal, InputChain);
1740 // If the node became dead and we haven't already seen it, delete it.
1741 if (ChainNode->use_empty() &&
1742 !std::count(NowDeadNodes.begin(), NowDeadNodes.end(), ChainNode))
1743 NowDeadNodes.push_back(ChainNode);
1747 // If the result produces glue, update any glue results in the matched
1748 // pattern with the glue result.
1749 if (InputGlue.getNode() != 0) {
1750 // Handle any interior nodes explicitly marked.
1751 for (unsigned i = 0, e = GlueResultNodesMatched.size(); i != e; ++i) {
1752 SDNode *FRN = GlueResultNodesMatched[i];
1754 // If this node was already deleted, don't look at it.
1755 if (FRN->getOpcode() == ISD::DELETED_NODE)
1758 assert(FRN->getValueType(FRN->getNumValues()-1) == MVT::Glue &&
1759 "Doesn't have a glue result");
1760 CurDAG->ReplaceAllUsesOfValueWith(SDValue(FRN, FRN->getNumValues()-1),
1763 // If the node became dead and we haven't already seen it, delete it.
1764 if (FRN->use_empty() &&
1765 !std::count(NowDeadNodes.begin(), NowDeadNodes.end(), FRN))
1766 NowDeadNodes.push_back(FRN);
1770 if (!NowDeadNodes.empty())
1771 CurDAG->RemoveDeadNodes(NowDeadNodes);
1773 DEBUG(errs() << "ISEL: Match complete!\n");
1779 CR_LeadsToInteriorNode
1782 /// WalkChainUsers - Walk down the users of the specified chained node that is
1783 /// part of the pattern we're matching, looking at all of the users we find.
1784 /// This determines whether something is an interior node, whether we have a
1785 /// non-pattern node in between two pattern nodes (which prevent folding because
1786 /// it would induce a cycle) and whether we have a TokenFactor node sandwiched
1787 /// between pattern nodes (in which case the TF becomes part of the pattern).
1789 /// The walk we do here is guaranteed to be small because we quickly get down to
1790 /// already selected nodes "below" us.
1792 WalkChainUsers(const SDNode *ChainedNode,
1793 SmallVectorImpl<SDNode*> &ChainedNodesInPattern,
1794 SmallVectorImpl<SDNode*> &InteriorChainedNodes) {
1795 ChainResult Result = CR_Simple;
1797 for (SDNode::use_iterator UI = ChainedNode->use_begin(),
1798 E = ChainedNode->use_end(); UI != E; ++UI) {
1799 // Make sure the use is of the chain, not some other value we produce.
1800 if (UI.getUse().getValueType() != MVT::Other) continue;
1804 // If we see an already-selected machine node, then we've gone beyond the
1805 // pattern that we're selecting down into the already selected chunk of the
1807 if (User->isMachineOpcode() ||
1808 User->getOpcode() == ISD::HANDLENODE) // Root of the graph.
1811 unsigned UserOpcode = User->getOpcode();
1812 if (UserOpcode == ISD::CopyToReg ||
1813 UserOpcode == ISD::CopyFromReg ||
1814 UserOpcode == ISD::INLINEASM ||
1815 UserOpcode == ISD::EH_LABEL ||
1816 UserOpcode == ISD::LIFETIME_START ||
1817 UserOpcode == ISD::LIFETIME_END) {
1818 // If their node ID got reset to -1 then they've already been selected.
1819 // Treat them like a MachineOpcode.
1820 if (User->getNodeId() == -1)
1824 // If we have a TokenFactor, we handle it specially.
1825 if (User->getOpcode() != ISD::TokenFactor) {
1826 // If the node isn't a token factor and isn't part of our pattern, then it
1827 // must be a random chained node in between two nodes we're selecting.
1828 // This happens when we have something like:
1833 // Because we structurally match the load/store as a read/modify/write,
1834 // but the call is chained between them. We cannot fold in this case
1835 // because it would induce a cycle in the graph.
1836 if (!std::count(ChainedNodesInPattern.begin(),
1837 ChainedNodesInPattern.end(), User))
1838 return CR_InducesCycle;
1840 // Otherwise we found a node that is part of our pattern. For example in:
1844 // This would happen when we're scanning down from the load and see the
1845 // store as a user. Record that there is a use of ChainedNode that is
1846 // part of the pattern and keep scanning uses.
1847 Result = CR_LeadsToInteriorNode;
1848 InteriorChainedNodes.push_back(User);
1852 // If we found a TokenFactor, there are two cases to consider: first if the
1853 // TokenFactor is just hanging "below" the pattern we're matching (i.e. no
1854 // uses of the TF are in our pattern) we just want to ignore it. Second,
1855 // the TokenFactor can be sandwiched in between two chained nodes, like so:
1861 // | \ DAG's like cheese
1864 // [TokenFactor] [Op]
1871 // In this case, the TokenFactor becomes part of our match and we rewrite it
1872 // as a new TokenFactor.
1874 // To distinguish these two cases, do a recursive walk down the uses.
1875 switch (WalkChainUsers(User, ChainedNodesInPattern, InteriorChainedNodes)) {
1877 // If the uses of the TokenFactor are just already-selected nodes, ignore
1878 // it, it is "below" our pattern.
1880 case CR_InducesCycle:
1881 // If the uses of the TokenFactor lead to nodes that are not part of our
1882 // pattern that are not selected, folding would turn this into a cycle,
1884 return CR_InducesCycle;
1885 case CR_LeadsToInteriorNode:
1886 break; // Otherwise, keep processing.
1889 // Okay, we know we're in the interesting interior case. The TokenFactor
1890 // is now going to be considered part of the pattern so that we rewrite its
1891 // uses (it may have uses that are not part of the pattern) with the
1892 // ultimate chain result of the generated code. We will also add its chain
1893 // inputs as inputs to the ultimate TokenFactor we create.
1894 Result = CR_LeadsToInteriorNode;
1895 ChainedNodesInPattern.push_back(User);
1896 InteriorChainedNodes.push_back(User);
1903 /// HandleMergeInputChains - This implements the OPC_EmitMergeInputChains
1904 /// operation for when the pattern matched at least one node with a chains. The
1905 /// input vector contains a list of all of the chained nodes that we match. We
1906 /// must determine if this is a valid thing to cover (i.e. matching it won't
1907 /// induce cycles in the DAG) and if so, creating a TokenFactor node. that will
1908 /// be used as the input node chain for the generated nodes.
1910 HandleMergeInputChains(SmallVectorImpl<SDNode*> &ChainNodesMatched,
1911 SelectionDAG *CurDAG) {
1912 // Walk all of the chained nodes we've matched, recursively scanning down the
1913 // users of the chain result. This adds any TokenFactor nodes that are caught
1914 // in between chained nodes to the chained and interior nodes list.
1915 SmallVector<SDNode*, 3> InteriorChainedNodes;
1916 for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) {
1917 if (WalkChainUsers(ChainNodesMatched[i], ChainNodesMatched,
1918 InteriorChainedNodes) == CR_InducesCycle)
1919 return SDValue(); // Would induce a cycle.
1922 // Okay, we have walked all the matched nodes and collected TokenFactor nodes
1923 // that we are interested in. Form our input TokenFactor node.
1924 SmallVector<SDValue, 3> InputChains;
1925 for (unsigned i = 0, e = ChainNodesMatched.size(); i != e; ++i) {
1926 // Add the input chain of this node to the InputChains list (which will be
1927 // the operands of the generated TokenFactor) if it's not an interior node.
1928 SDNode *N = ChainNodesMatched[i];
1929 if (N->getOpcode() != ISD::TokenFactor) {
1930 if (std::count(InteriorChainedNodes.begin(),InteriorChainedNodes.end(),N))
1933 // Otherwise, add the input chain.
1934 SDValue InChain = ChainNodesMatched[i]->getOperand(0);
1935 assert(InChain.getValueType() == MVT::Other && "Not a chain");
1936 InputChains.push_back(InChain);
1940 // If we have a token factor, we want to add all inputs of the token factor
1941 // that are not part of the pattern we're matching.
1942 for (unsigned op = 0, e = N->getNumOperands(); op != e; ++op) {
1943 if (!std::count(ChainNodesMatched.begin(), ChainNodesMatched.end(),
1944 N->getOperand(op).getNode()))
1945 InputChains.push_back(N->getOperand(op));
1950 if (InputChains.size() == 1)
1951 return InputChains[0];
1952 return CurDAG->getNode(ISD::TokenFactor, ChainNodesMatched[0]->getDebugLoc(),
1953 MVT::Other, &InputChains[0], InputChains.size());
1956 /// MorphNode - Handle morphing a node in place for the selector.
1957 SDNode *SelectionDAGISel::
1958 MorphNode(SDNode *Node, unsigned TargetOpc, SDVTList VTList,
1959 const SDValue *Ops, unsigned NumOps, unsigned EmitNodeInfo) {
1960 // It is possible we're using MorphNodeTo to replace a node with no
1961 // normal results with one that has a normal result (or we could be
1962 // adding a chain) and the input could have glue and chains as well.
1963 // In this case we need to shift the operands down.
1964 // FIXME: This is a horrible hack and broken in obscure cases, no worse
1965 // than the old isel though.
1966 int OldGlueResultNo = -1, OldChainResultNo = -1;
1968 unsigned NTMNumResults = Node->getNumValues();
1969 if (Node->getValueType(NTMNumResults-1) == MVT::Glue) {
1970 OldGlueResultNo = NTMNumResults-1;
1971 if (NTMNumResults != 1 &&
1972 Node->getValueType(NTMNumResults-2) == MVT::Other)
1973 OldChainResultNo = NTMNumResults-2;
1974 } else if (Node->getValueType(NTMNumResults-1) == MVT::Other)
1975 OldChainResultNo = NTMNumResults-1;
1977 // Call the underlying SelectionDAG routine to do the transmogrification. Note
1978 // that this deletes operands of the old node that become dead.
1979 SDNode *Res = CurDAG->MorphNodeTo(Node, ~TargetOpc, VTList, Ops, NumOps);
1981 // MorphNodeTo can operate in two ways: if an existing node with the
1982 // specified operands exists, it can just return it. Otherwise, it
1983 // updates the node in place to have the requested operands.
1985 // If we updated the node in place, reset the node ID. To the isel,
1986 // this should be just like a newly allocated machine node.
1990 unsigned ResNumResults = Res->getNumValues();
1991 // Move the glue if needed.
1992 if ((EmitNodeInfo & OPFL_GlueOutput) && OldGlueResultNo != -1 &&
1993 (unsigned)OldGlueResultNo != ResNumResults-1)
1994 CurDAG->ReplaceAllUsesOfValueWith(SDValue(Node, OldGlueResultNo),
1995 SDValue(Res, ResNumResults-1));
1997 if ((EmitNodeInfo & OPFL_GlueOutput) != 0)
2000 // Move the chain reference if needed.
2001 if ((EmitNodeInfo & OPFL_Chain) && OldChainResultNo != -1 &&
2002 (unsigned)OldChainResultNo != ResNumResults-1)
2003 CurDAG->ReplaceAllUsesOfValueWith(SDValue(Node, OldChainResultNo),
2004 SDValue(Res, ResNumResults-1));
2006 // Otherwise, no replacement happened because the node already exists. Replace
2007 // Uses of the old node with the new one.
2009 CurDAG->ReplaceAllUsesWith(Node, Res);
2014 /// CheckSame - Implements OP_CheckSame.
2015 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2016 CheckSame(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2018 const SmallVectorImpl<std::pair<SDValue, SDNode*> > &RecordedNodes) {
2019 // Accept if it is exactly the same as a previously recorded node.
2020 unsigned RecNo = MatcherTable[MatcherIndex++];
2021 assert(RecNo < RecordedNodes.size() && "Invalid CheckSame");
2022 return N == RecordedNodes[RecNo].first;
2025 /// CheckPatternPredicate - Implements OP_CheckPatternPredicate.
2026 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2027 CheckPatternPredicate(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2028 const SelectionDAGISel &SDISel) {
2029 return SDISel.CheckPatternPredicate(MatcherTable[MatcherIndex++]);
2032 /// CheckNodePredicate - Implements OP_CheckNodePredicate.
2033 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2034 CheckNodePredicate(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2035 const SelectionDAGISel &SDISel, SDNode *N) {
2036 return SDISel.CheckNodePredicate(N, MatcherTable[MatcherIndex++]);
2039 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2040 CheckOpcode(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2042 uint16_t Opc = MatcherTable[MatcherIndex++];
2043 Opc |= (unsigned short)MatcherTable[MatcherIndex++] << 8;
2044 return N->getOpcode() == Opc;
2047 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2048 CheckType(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2049 SDValue N, const TargetLowering &TLI) {
2050 MVT::SimpleValueType VT = (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2051 if (N.getValueType() == VT) return true;
2053 // Handle the case when VT is iPTR.
2054 return VT == MVT::iPTR && N.getValueType() == TLI.getPointerTy();
2057 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2058 CheckChildType(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2059 SDValue N, const TargetLowering &TLI,
2061 if (ChildNo >= N.getNumOperands())
2062 return false; // Match fails if out of range child #.
2063 return ::CheckType(MatcherTable, MatcherIndex, N.getOperand(ChildNo), TLI);
2067 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2068 CheckCondCode(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2070 return cast<CondCodeSDNode>(N)->get() ==
2071 (ISD::CondCode)MatcherTable[MatcherIndex++];
2074 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2075 CheckValueType(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2076 SDValue N, const TargetLowering &TLI) {
2077 MVT::SimpleValueType VT = (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2078 if (cast<VTSDNode>(N)->getVT() == VT)
2081 // Handle the case when VT is iPTR.
2082 return VT == MVT::iPTR && cast<VTSDNode>(N)->getVT() == TLI.getPointerTy();
2085 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2086 CheckInteger(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2088 int64_t Val = MatcherTable[MatcherIndex++];
2090 Val = GetVBR(Val, MatcherTable, MatcherIndex);
2092 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N);
2093 return C != 0 && C->getSExtValue() == Val;
2096 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2097 CheckAndImm(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2098 SDValue N, const SelectionDAGISel &SDISel) {
2099 int64_t Val = MatcherTable[MatcherIndex++];
2101 Val = GetVBR(Val, MatcherTable, MatcherIndex);
2103 if (N->getOpcode() != ISD::AND) return false;
2105 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N->getOperand(1));
2106 return C != 0 && SDISel.CheckAndMask(N.getOperand(0), C, Val);
2109 LLVM_ATTRIBUTE_ALWAYS_INLINE static bool
2110 CheckOrImm(const unsigned char *MatcherTable, unsigned &MatcherIndex,
2111 SDValue N, const SelectionDAGISel &SDISel) {
2112 int64_t Val = MatcherTable[MatcherIndex++];
2114 Val = GetVBR(Val, MatcherTable, MatcherIndex);
2116 if (N->getOpcode() != ISD::OR) return false;
2118 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N->getOperand(1));
2119 return C != 0 && SDISel.CheckOrMask(N.getOperand(0), C, Val);
2122 /// IsPredicateKnownToFail - If we know how and can do so without pushing a
2123 /// scope, evaluate the current node. If the current predicate is known to
2124 /// fail, set Result=true and return anything. If the current predicate is
2125 /// known to pass, set Result=false and return the MatcherIndex to continue
2126 /// with. If the current predicate is unknown, set Result=false and return the
2127 /// MatcherIndex to continue with.
2128 static unsigned IsPredicateKnownToFail(const unsigned char *Table,
2129 unsigned Index, SDValue N,
2131 const SelectionDAGISel &SDISel,
2132 SmallVectorImpl<std::pair<SDValue, SDNode*> > &RecordedNodes) {
2133 switch (Table[Index++]) {
2136 return Index-1; // Could not evaluate this predicate.
2137 case SelectionDAGISel::OPC_CheckSame:
2138 Result = !::CheckSame(Table, Index, N, RecordedNodes);
2140 case SelectionDAGISel::OPC_CheckPatternPredicate:
2141 Result = !::CheckPatternPredicate(Table, Index, SDISel);
2143 case SelectionDAGISel::OPC_CheckPredicate:
2144 Result = !::CheckNodePredicate(Table, Index, SDISel, N.getNode());
2146 case SelectionDAGISel::OPC_CheckOpcode:
2147 Result = !::CheckOpcode(Table, Index, N.getNode());
2149 case SelectionDAGISel::OPC_CheckType:
2150 Result = !::CheckType(Table, Index, N, SDISel.TLI);
2152 case SelectionDAGISel::OPC_CheckChild0Type:
2153 case SelectionDAGISel::OPC_CheckChild1Type:
2154 case SelectionDAGISel::OPC_CheckChild2Type:
2155 case SelectionDAGISel::OPC_CheckChild3Type:
2156 case SelectionDAGISel::OPC_CheckChild4Type:
2157 case SelectionDAGISel::OPC_CheckChild5Type:
2158 case SelectionDAGISel::OPC_CheckChild6Type:
2159 case SelectionDAGISel::OPC_CheckChild7Type:
2160 Result = !::CheckChildType(Table, Index, N, SDISel.TLI,
2161 Table[Index-1] - SelectionDAGISel::OPC_CheckChild0Type);
2163 case SelectionDAGISel::OPC_CheckCondCode:
2164 Result = !::CheckCondCode(Table, Index, N);
2166 case SelectionDAGISel::OPC_CheckValueType:
2167 Result = !::CheckValueType(Table, Index, N, SDISel.TLI);
2169 case SelectionDAGISel::OPC_CheckInteger:
2170 Result = !::CheckInteger(Table, Index, N);
2172 case SelectionDAGISel::OPC_CheckAndImm:
2173 Result = !::CheckAndImm(Table, Index, N, SDISel);
2175 case SelectionDAGISel::OPC_CheckOrImm:
2176 Result = !::CheckOrImm(Table, Index, N, SDISel);
2184 /// FailIndex - If this match fails, this is the index to continue with.
2187 /// NodeStack - The node stack when the scope was formed.
2188 SmallVector<SDValue, 4> NodeStack;
2190 /// NumRecordedNodes - The number of recorded nodes when the scope was formed.
2191 unsigned NumRecordedNodes;
2193 /// NumMatchedMemRefs - The number of matched memref entries.
2194 unsigned NumMatchedMemRefs;
2196 /// InputChain/InputGlue - The current chain/glue
2197 SDValue InputChain, InputGlue;
2199 /// HasChainNodesMatched - True if the ChainNodesMatched list is non-empty.
2200 bool HasChainNodesMatched, HasGlueResultNodesMatched;
2205 SDNode *SelectionDAGISel::
2206 SelectCodeCommon(SDNode *NodeToMatch, const unsigned char *MatcherTable,
2207 unsigned TableSize) {
2208 // FIXME: Should these even be selected? Handle these cases in the caller?
2209 switch (NodeToMatch->getOpcode()) {
2212 case ISD::EntryToken: // These nodes remain the same.
2213 case ISD::BasicBlock:
2215 case ISD::RegisterMask:
2216 //case ISD::VALUETYPE:
2217 //case ISD::CONDCODE:
2218 case ISD::HANDLENODE:
2219 case ISD::MDNODE_SDNODE:
2220 case ISD::TargetConstant:
2221 case ISD::TargetConstantFP:
2222 case ISD::TargetConstantPool:
2223 case ISD::TargetFrameIndex:
2224 case ISD::TargetExternalSymbol:
2225 case ISD::TargetBlockAddress:
2226 case ISD::TargetJumpTable:
2227 case ISD::TargetGlobalTLSAddress:
2228 case ISD::TargetGlobalAddress:
2229 case ISD::TokenFactor:
2230 case ISD::CopyFromReg:
2231 case ISD::CopyToReg:
2233 case ISD::LIFETIME_START:
2234 case ISD::LIFETIME_END:
2235 NodeToMatch->setNodeId(-1); // Mark selected.
2237 case ISD::AssertSext:
2238 case ISD::AssertZext:
2239 CurDAG->ReplaceAllUsesOfValueWith(SDValue(NodeToMatch, 0),
2240 NodeToMatch->getOperand(0));
2242 case ISD::INLINEASM: return Select_INLINEASM(NodeToMatch);
2243 case ISD::UNDEF: return Select_UNDEF(NodeToMatch);
2246 assert(!NodeToMatch->isMachineOpcode() && "Node already selected!");
2248 // Set up the node stack with NodeToMatch as the only node on the stack.
2249 SmallVector<SDValue, 8> NodeStack;
2250 SDValue N = SDValue(NodeToMatch, 0);
2251 NodeStack.push_back(N);
2253 // MatchScopes - Scopes used when matching, if a match failure happens, this
2254 // indicates where to continue checking.
2255 SmallVector<MatchScope, 8> MatchScopes;
2257 // RecordedNodes - This is the set of nodes that have been recorded by the
2258 // state machine. The second value is the parent of the node, or null if the
2259 // root is recorded.
2260 SmallVector<std::pair<SDValue, SDNode*>, 8> RecordedNodes;
2262 // MatchedMemRefs - This is the set of MemRef's we've seen in the input
2264 SmallVector<MachineMemOperand*, 2> MatchedMemRefs;
2266 // These are the current input chain and glue for use when generating nodes.
2267 // Various Emit operations change these. For example, emitting a copytoreg
2268 // uses and updates these.
2269 SDValue InputChain, InputGlue;
2271 // ChainNodesMatched - If a pattern matches nodes that have input/output
2272 // chains, the OPC_EmitMergeInputChains operation is emitted which indicates
2273 // which ones they are. The result is captured into this list so that we can
2274 // update the chain results when the pattern is complete.
2275 SmallVector<SDNode*, 3> ChainNodesMatched;
2276 SmallVector<SDNode*, 3> GlueResultNodesMatched;
2278 DEBUG(errs() << "ISEL: Starting pattern match on root node: ";
2279 NodeToMatch->dump(CurDAG);
2282 // Determine where to start the interpreter. Normally we start at opcode #0,
2283 // but if the state machine starts with an OPC_SwitchOpcode, then we
2284 // accelerate the first lookup (which is guaranteed to be hot) with the
2285 // OpcodeOffset table.
2286 unsigned MatcherIndex = 0;
2288 if (!OpcodeOffset.empty()) {
2289 // Already computed the OpcodeOffset table, just index into it.
2290 if (N.getOpcode() < OpcodeOffset.size())
2291 MatcherIndex = OpcodeOffset[N.getOpcode()];
2292 DEBUG(errs() << " Initial Opcode index to " << MatcherIndex << "\n");
2294 } else if (MatcherTable[0] == OPC_SwitchOpcode) {
2295 // Otherwise, the table isn't computed, but the state machine does start
2296 // with an OPC_SwitchOpcode instruction. Populate the table now, since this
2297 // is the first time we're selecting an instruction.
2300 // Get the size of this case.
2301 unsigned CaseSize = MatcherTable[Idx++];
2303 CaseSize = GetVBR(CaseSize, MatcherTable, Idx);
2304 if (CaseSize == 0) break;
2306 // Get the opcode, add the index to the table.
2307 uint16_t Opc = MatcherTable[Idx++];
2308 Opc |= (unsigned short)MatcherTable[Idx++] << 8;
2309 if (Opc >= OpcodeOffset.size())
2310 OpcodeOffset.resize((Opc+1)*2);
2311 OpcodeOffset[Opc] = Idx;
2315 // Okay, do the lookup for the first opcode.
2316 if (N.getOpcode() < OpcodeOffset.size())
2317 MatcherIndex = OpcodeOffset[N.getOpcode()];
2321 assert(MatcherIndex < TableSize && "Invalid index");
2323 unsigned CurrentOpcodeIndex = MatcherIndex;
2325 BuiltinOpcodes Opcode = (BuiltinOpcodes)MatcherTable[MatcherIndex++];
2328 // Okay, the semantics of this operation are that we should push a scope
2329 // then evaluate the first child. However, pushing a scope only to have
2330 // the first check fail (which then pops it) is inefficient. If we can
2331 // determine immediately that the first check (or first several) will
2332 // immediately fail, don't even bother pushing a scope for them.
2336 unsigned NumToSkip = MatcherTable[MatcherIndex++];
2337 if (NumToSkip & 128)
2338 NumToSkip = GetVBR(NumToSkip, MatcherTable, MatcherIndex);
2339 // Found the end of the scope with no match.
2340 if (NumToSkip == 0) {
2345 FailIndex = MatcherIndex+NumToSkip;
2347 unsigned MatcherIndexOfPredicate = MatcherIndex;
2348 (void)MatcherIndexOfPredicate; // silence warning.
2350 // If we can't evaluate this predicate without pushing a scope (e.g. if
2351 // it is a 'MoveParent') or if the predicate succeeds on this node, we
2352 // push the scope and evaluate the full predicate chain.
2354 MatcherIndex = IsPredicateKnownToFail(MatcherTable, MatcherIndex, N,
2355 Result, *this, RecordedNodes);
2359 DEBUG(errs() << " Skipped scope entry (due to false predicate) at "
2360 << "index " << MatcherIndexOfPredicate
2361 << ", continuing at " << FailIndex << "\n");
2362 ++NumDAGIselRetries;
2364 // Otherwise, we know that this case of the Scope is guaranteed to fail,
2365 // move to the next case.
2366 MatcherIndex = FailIndex;
2369 // If the whole scope failed to match, bail.
2370 if (FailIndex == 0) break;
2372 // Push a MatchScope which indicates where to go if the first child fails
2374 MatchScope NewEntry;
2375 NewEntry.FailIndex = FailIndex;
2376 NewEntry.NodeStack.append(NodeStack.begin(), NodeStack.end());
2377 NewEntry.NumRecordedNodes = RecordedNodes.size();
2378 NewEntry.NumMatchedMemRefs = MatchedMemRefs.size();
2379 NewEntry.InputChain = InputChain;
2380 NewEntry.InputGlue = InputGlue;
2381 NewEntry.HasChainNodesMatched = !ChainNodesMatched.empty();
2382 NewEntry.HasGlueResultNodesMatched = !GlueResultNodesMatched.empty();
2383 MatchScopes.push_back(NewEntry);
2386 case OPC_RecordNode: {
2387 // Remember this node, it may end up being an operand in the pattern.
2389 if (NodeStack.size() > 1)
2390 Parent = NodeStack[NodeStack.size()-2].getNode();
2391 RecordedNodes.push_back(std::make_pair(N, Parent));
2395 case OPC_RecordChild0: case OPC_RecordChild1:
2396 case OPC_RecordChild2: case OPC_RecordChild3:
2397 case OPC_RecordChild4: case OPC_RecordChild5:
2398 case OPC_RecordChild6: case OPC_RecordChild7: {
2399 unsigned ChildNo = Opcode-OPC_RecordChild0;
2400 if (ChildNo >= N.getNumOperands())
2401 break; // Match fails if out of range child #.
2403 RecordedNodes.push_back(std::make_pair(N->getOperand(ChildNo),
2407 case OPC_RecordMemRef:
2408 MatchedMemRefs.push_back(cast<MemSDNode>(N)->getMemOperand());
2411 case OPC_CaptureGlueInput:
2412 // If the current node has an input glue, capture it in InputGlue.
2413 if (N->getNumOperands() != 0 &&
2414 N->getOperand(N->getNumOperands()-1).getValueType() == MVT::Glue)
2415 InputGlue = N->getOperand(N->getNumOperands()-1);
2418 case OPC_MoveChild: {
2419 unsigned ChildNo = MatcherTable[MatcherIndex++];
2420 if (ChildNo >= N.getNumOperands())
2421 break; // Match fails if out of range child #.
2422 N = N.getOperand(ChildNo);
2423 NodeStack.push_back(N);
2427 case OPC_MoveParent:
2428 // Pop the current node off the NodeStack.
2429 NodeStack.pop_back();
2430 assert(!NodeStack.empty() && "Node stack imbalance!");
2431 N = NodeStack.back();
2435 if (!::CheckSame(MatcherTable, MatcherIndex, N, RecordedNodes)) break;
2437 case OPC_CheckPatternPredicate:
2438 if (!::CheckPatternPredicate(MatcherTable, MatcherIndex, *this)) break;
2440 case OPC_CheckPredicate:
2441 if (!::CheckNodePredicate(MatcherTable, MatcherIndex, *this,
2445 case OPC_CheckComplexPat: {
2446 unsigned CPNum = MatcherTable[MatcherIndex++];
2447 unsigned RecNo = MatcherTable[MatcherIndex++];
2448 assert(RecNo < RecordedNodes.size() && "Invalid CheckComplexPat");
2449 if (!CheckComplexPattern(NodeToMatch, RecordedNodes[RecNo].second,
2450 RecordedNodes[RecNo].first, CPNum,
2455 case OPC_CheckOpcode:
2456 if (!::CheckOpcode(MatcherTable, MatcherIndex, N.getNode())) break;
2460 if (!::CheckType(MatcherTable, MatcherIndex, N, TLI)) break;
2463 case OPC_SwitchOpcode: {
2464 unsigned CurNodeOpcode = N.getOpcode();
2465 unsigned SwitchStart = MatcherIndex-1; (void)SwitchStart;
2468 // Get the size of this case.
2469 CaseSize = MatcherTable[MatcherIndex++];
2471 CaseSize = GetVBR(CaseSize, MatcherTable, MatcherIndex);
2472 if (CaseSize == 0) break;
2474 uint16_t Opc = MatcherTable[MatcherIndex++];
2475 Opc |= (unsigned short)MatcherTable[MatcherIndex++] << 8;
2477 // If the opcode matches, then we will execute this case.
2478 if (CurNodeOpcode == Opc)
2481 // Otherwise, skip over this case.
2482 MatcherIndex += CaseSize;
2485 // If no cases matched, bail out.
2486 if (CaseSize == 0) break;
2488 // Otherwise, execute the case we found.
2489 DEBUG(errs() << " OpcodeSwitch from " << SwitchStart
2490 << " to " << MatcherIndex << "\n");
2494 case OPC_SwitchType: {
2495 MVT CurNodeVT = N.getValueType().getSimpleVT();
2496 unsigned SwitchStart = MatcherIndex-1; (void)SwitchStart;
2499 // Get the size of this case.
2500 CaseSize = MatcherTable[MatcherIndex++];
2502 CaseSize = GetVBR(CaseSize, MatcherTable, MatcherIndex);
2503 if (CaseSize == 0) break;
2505 MVT CaseVT = (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2506 if (CaseVT == MVT::iPTR)
2507 CaseVT = TLI.getPointerTy();
2509 // If the VT matches, then we will execute this case.
2510 if (CurNodeVT == CaseVT)
2513 // Otherwise, skip over this case.
2514 MatcherIndex += CaseSize;
2517 // If no cases matched, bail out.
2518 if (CaseSize == 0) break;
2520 // Otherwise, execute the case we found.
2521 DEBUG(errs() << " TypeSwitch[" << EVT(CurNodeVT).getEVTString()
2522 << "] from " << SwitchStart << " to " << MatcherIndex<<'\n');
2525 case OPC_CheckChild0Type: case OPC_CheckChild1Type:
2526 case OPC_CheckChild2Type: case OPC_CheckChild3Type:
2527 case OPC_CheckChild4Type: case OPC_CheckChild5Type:
2528 case OPC_CheckChild6Type: case OPC_CheckChild7Type:
2529 if (!::CheckChildType(MatcherTable, MatcherIndex, N, TLI,
2530 Opcode-OPC_CheckChild0Type))
2533 case OPC_CheckCondCode:
2534 if (!::CheckCondCode(MatcherTable, MatcherIndex, N)) break;
2536 case OPC_CheckValueType:
2537 if (!::CheckValueType(MatcherTable, MatcherIndex, N, TLI)) break;
2539 case OPC_CheckInteger:
2540 if (!::CheckInteger(MatcherTable, MatcherIndex, N)) break;
2542 case OPC_CheckAndImm:
2543 if (!::CheckAndImm(MatcherTable, MatcherIndex, N, *this)) break;
2545 case OPC_CheckOrImm:
2546 if (!::CheckOrImm(MatcherTable, MatcherIndex, N, *this)) break;
2549 case OPC_CheckFoldableChainNode: {
2550 assert(NodeStack.size() != 1 && "No parent node");
2551 // Verify that all intermediate nodes between the root and this one have
2553 bool HasMultipleUses = false;
2554 for (unsigned i = 1, e = NodeStack.size()-1; i != e; ++i)
2555 if (!NodeStack[i].hasOneUse()) {
2556 HasMultipleUses = true;
2559 if (HasMultipleUses) break;
2561 // Check to see that the target thinks this is profitable to fold and that
2562 // we can fold it without inducing cycles in the graph.
2563 if (!IsProfitableToFold(N, NodeStack[NodeStack.size()-2].getNode(),
2565 !IsLegalToFold(N, NodeStack[NodeStack.size()-2].getNode(),
2566 NodeToMatch, OptLevel,
2567 true/*We validate our own chains*/))
2572 case OPC_EmitInteger: {
2573 MVT::SimpleValueType VT =
2574 (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2575 int64_t Val = MatcherTable[MatcherIndex++];
2577 Val = GetVBR(Val, MatcherTable, MatcherIndex);
2578 RecordedNodes.push_back(std::pair<SDValue, SDNode*>(
2579 CurDAG->getTargetConstant(Val, VT), (SDNode*)0));
2582 case OPC_EmitRegister: {
2583 MVT::SimpleValueType VT =
2584 (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2585 unsigned RegNo = MatcherTable[MatcherIndex++];
2586 RecordedNodes.push_back(std::pair<SDValue, SDNode*>(
2587 CurDAG->getRegister(RegNo, VT), (SDNode*)0));
2590 case OPC_EmitRegister2: {
2591 // For targets w/ more than 256 register names, the register enum
2592 // values are stored in two bytes in the matcher table (just like
2594 MVT::SimpleValueType VT =
2595 (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2596 unsigned RegNo = MatcherTable[MatcherIndex++];
2597 RegNo |= MatcherTable[MatcherIndex++] << 8;
2598 RecordedNodes.push_back(std::pair<SDValue, SDNode*>(
2599 CurDAG->getRegister(RegNo, VT), (SDNode*)0));
2603 case OPC_EmitConvertToTarget: {
2604 // Convert from IMM/FPIMM to target version.
2605 unsigned RecNo = MatcherTable[MatcherIndex++];
2606 assert(RecNo < RecordedNodes.size() && "Invalid CheckSame");
2607 SDValue Imm = RecordedNodes[RecNo].first;
2609 if (Imm->getOpcode() == ISD::Constant) {
2610 int64_t Val = cast<ConstantSDNode>(Imm)->getZExtValue();
2611 Imm = CurDAG->getTargetConstant(Val, Imm.getValueType());
2612 } else if (Imm->getOpcode() == ISD::ConstantFP) {
2613 const ConstantFP *Val=cast<ConstantFPSDNode>(Imm)->getConstantFPValue();
2614 Imm = CurDAG->getTargetConstantFP(*Val, Imm.getValueType());
2617 RecordedNodes.push_back(std::make_pair(Imm, RecordedNodes[RecNo].second));
2621 case OPC_EmitMergeInputChains1_0: // OPC_EmitMergeInputChains, 1, 0
2622 case OPC_EmitMergeInputChains1_1: { // OPC_EmitMergeInputChains, 1, 1
2623 // These are space-optimized forms of OPC_EmitMergeInputChains.
2624 assert(InputChain.getNode() == 0 &&
2625 "EmitMergeInputChains should be the first chain producing node");
2626 assert(ChainNodesMatched.empty() &&
2627 "Should only have one EmitMergeInputChains per match");
2629 // Read all of the chained nodes.
2630 unsigned RecNo = Opcode == OPC_EmitMergeInputChains1_1;
2631 assert(RecNo < RecordedNodes.size() && "Invalid CheckSame");
2632 ChainNodesMatched.push_back(RecordedNodes[RecNo].first.getNode());
2634 // FIXME: What if other value results of the node have uses not matched
2636 if (ChainNodesMatched.back() != NodeToMatch &&
2637 !RecordedNodes[RecNo].first.hasOneUse()) {
2638 ChainNodesMatched.clear();
2642 // Merge the input chains if they are not intra-pattern references.
2643 InputChain = HandleMergeInputChains(ChainNodesMatched, CurDAG);
2645 if (InputChain.getNode() == 0)
2646 break; // Failed to merge.
2650 case OPC_EmitMergeInputChains: {
2651 assert(InputChain.getNode() == 0 &&
2652 "EmitMergeInputChains should be the first chain producing node");
2653 // This node gets a list of nodes we matched in the input that have
2654 // chains. We want to token factor all of the input chains to these nodes
2655 // together. However, if any of the input chains is actually one of the
2656 // nodes matched in this pattern, then we have an intra-match reference.
2657 // Ignore these because the newly token factored chain should not refer to
2659 unsigned NumChains = MatcherTable[MatcherIndex++];
2660 assert(NumChains != 0 && "Can't TF zero chains");
2662 assert(ChainNodesMatched.empty() &&
2663 "Should only have one EmitMergeInputChains per match");
2665 // Read all of the chained nodes.
2666 for (unsigned i = 0; i != NumChains; ++i) {
2667 unsigned RecNo = MatcherTable[MatcherIndex++];
2668 assert(RecNo < RecordedNodes.size() && "Invalid CheckSame");
2669 ChainNodesMatched.push_back(RecordedNodes[RecNo].first.getNode());
2671 // FIXME: What if other value results of the node have uses not matched
2673 if (ChainNodesMatched.back() != NodeToMatch &&
2674 !RecordedNodes[RecNo].first.hasOneUse()) {
2675 ChainNodesMatched.clear();
2680 // If the inner loop broke out, the match fails.
2681 if (ChainNodesMatched.empty())
2684 // Merge the input chains if they are not intra-pattern references.
2685 InputChain = HandleMergeInputChains(ChainNodesMatched, CurDAG);
2687 if (InputChain.getNode() == 0)
2688 break; // Failed to merge.
2693 case OPC_EmitCopyToReg: {
2694 unsigned RecNo = MatcherTable[MatcherIndex++];
2695 assert(RecNo < RecordedNodes.size() && "Invalid CheckSame");
2696 unsigned DestPhysReg = MatcherTable[MatcherIndex++];
2698 if (InputChain.getNode() == 0)
2699 InputChain = CurDAG->getEntryNode();
2701 InputChain = CurDAG->getCopyToReg(InputChain, NodeToMatch->getDebugLoc(),
2702 DestPhysReg, RecordedNodes[RecNo].first,
2705 InputGlue = InputChain.getValue(1);
2709 case OPC_EmitNodeXForm: {
2710 unsigned XFormNo = MatcherTable[MatcherIndex++];
2711 unsigned RecNo = MatcherTable[MatcherIndex++];
2712 assert(RecNo < RecordedNodes.size() && "Invalid CheckSame");
2713 SDValue Res = RunSDNodeXForm(RecordedNodes[RecNo].first, XFormNo);
2714 RecordedNodes.push_back(std::pair<SDValue,SDNode*>(Res, (SDNode*) 0));
2719 case OPC_MorphNodeTo: {
2720 uint16_t TargetOpc = MatcherTable[MatcherIndex++];
2721 TargetOpc |= (unsigned short)MatcherTable[MatcherIndex++] << 8;
2722 unsigned EmitNodeInfo = MatcherTable[MatcherIndex++];
2723 // Get the result VT list.
2724 unsigned NumVTs = MatcherTable[MatcherIndex++];
2725 SmallVector<EVT, 4> VTs;
2726 for (unsigned i = 0; i != NumVTs; ++i) {
2727 MVT::SimpleValueType VT =
2728 (MVT::SimpleValueType)MatcherTable[MatcherIndex++];
2729 if (VT == MVT::iPTR) VT = TLI.getPointerTy().SimpleTy;
2733 if (EmitNodeInfo & OPFL_Chain)
2734 VTs.push_back(MVT::Other);
2735 if (EmitNodeInfo & OPFL_GlueOutput)
2736 VTs.push_back(MVT::Glue);
2738 // This is hot code, so optimize the two most common cases of 1 and 2
2741 if (VTs.size() == 1)
2742 VTList = CurDAG->getVTList(VTs[0]);
2743 else if (VTs.size() == 2)
2744 VTList = CurDAG->getVTList(VTs[0], VTs[1]);
2746 VTList = CurDAG->getVTList(VTs.data(), VTs.size());
2748 // Get the operand list.
2749 unsigned NumOps = MatcherTable[MatcherIndex++];
2750 SmallVector<SDValue, 8> Ops;
2751 for (unsigned i = 0; i != NumOps; ++i) {
2752 unsigned RecNo = MatcherTable[MatcherIndex++];
2754 RecNo = GetVBR(RecNo, MatcherTable, MatcherIndex);
2756 assert(RecNo < RecordedNodes.size() && "Invalid EmitNode");
2757 Ops.push_back(RecordedNodes[RecNo].first);
2760 // If there are variadic operands to add, handle them now.
2761 if (EmitNodeInfo & OPFL_VariadicInfo) {
2762 // Determine the start index to copy from.
2763 unsigned FirstOpToCopy = getNumFixedFromVariadicInfo(EmitNodeInfo);
2764 FirstOpToCopy += (EmitNodeInfo & OPFL_Chain) ? 1 : 0;
2765 assert(NodeToMatch->getNumOperands() >= FirstOpToCopy &&
2766 "Invalid variadic node");
2767 // Copy all of the variadic operands, not including a potential glue
2769 for (unsigned i = FirstOpToCopy, e = NodeToMatch->getNumOperands();
2771 SDValue V = NodeToMatch->getOperand(i);
2772 if (V.getValueType() == MVT::Glue) break;
2777 // If this has chain/glue inputs, add them.
2778 if (EmitNodeInfo & OPFL_Chain)
2779 Ops.push_back(InputChain);
2780 if ((EmitNodeInfo & OPFL_GlueInput) && InputGlue.getNode() != 0)
2781 Ops.push_back(InputGlue);
2785 if (Opcode != OPC_MorphNodeTo) {
2786 // If this is a normal EmitNode command, just create the new node and
2787 // add the results to the RecordedNodes list.
2788 Res = CurDAG->getMachineNode(TargetOpc, NodeToMatch->getDebugLoc(),
2789 VTList, Ops.data(), Ops.size());
2791 // Add all the non-glue/non-chain results to the RecordedNodes list.
2792 for (unsigned i = 0, e = VTs.size(); i != e; ++i) {
2793 if (VTs[i] == MVT::Other || VTs[i] == MVT::Glue) break;
2794 RecordedNodes.push_back(std::pair<SDValue,SDNode*>(SDValue(Res, i),
2798 } else if (NodeToMatch->getOpcode() != ISD::DELETED_NODE) {
2799 Res = MorphNode(NodeToMatch, TargetOpc, VTList, Ops.data(), Ops.size(),
2802 // NodeToMatch was eliminated by CSE when the target changed the DAG.
2803 // We will visit the equivalent node later.
2804 DEBUG(dbgs() << "Node was eliminated by CSE\n");
2808 // If the node had chain/glue results, update our notion of the current
2810 if (EmitNodeInfo & OPFL_GlueOutput) {
2811 InputGlue = SDValue(Res, VTs.size()-1);
2812 if (EmitNodeInfo & OPFL_Chain)
2813 InputChain = SDValue(Res, VTs.size()-2);
2814 } else if (EmitNodeInfo & OPFL_Chain)
2815 InputChain = SDValue(Res, VTs.size()-1);
2817 // If the OPFL_MemRefs glue is set on this node, slap all of the
2818 // accumulated memrefs onto it.
2820 // FIXME: This is vastly incorrect for patterns with multiple outputs
2821 // instructions that access memory and for ComplexPatterns that match
2823 if (EmitNodeInfo & OPFL_MemRefs) {
2824 // Only attach load or store memory operands if the generated
2825 // instruction may load or store.
2826 const MCInstrDesc &MCID = TM.getInstrInfo()->get(TargetOpc);
2827 bool mayLoad = MCID.mayLoad();
2828 bool mayStore = MCID.mayStore();
2830 unsigned NumMemRefs = 0;
2831 for (SmallVector<MachineMemOperand*, 2>::const_iterator I =
2832 MatchedMemRefs.begin(), E = MatchedMemRefs.end(); I != E; ++I) {
2833 if ((*I)->isLoad()) {
2836 } else if ((*I)->isStore()) {
2844 MachineSDNode::mmo_iterator MemRefs =
2845 MF->allocateMemRefsArray(NumMemRefs);
2847 MachineSDNode::mmo_iterator MemRefsPos = MemRefs;
2848 for (SmallVector<MachineMemOperand*, 2>::const_iterator I =
2849 MatchedMemRefs.begin(), E = MatchedMemRefs.end(); I != E; ++I) {
2850 if ((*I)->isLoad()) {
2853 } else if ((*I)->isStore()) {
2861 cast<MachineSDNode>(Res)
2862 ->setMemRefs(MemRefs, MemRefs + NumMemRefs);
2866 << (Opcode == OPC_MorphNodeTo ? "Morphed" : "Created")
2867 << " node: "; Res->dump(CurDAG); errs() << "\n");
2869 // If this was a MorphNodeTo then we're completely done!
2870 if (Opcode == OPC_MorphNodeTo) {
2871 // Update chain and glue uses.
2872 UpdateChainsAndGlue(NodeToMatch, InputChain, ChainNodesMatched,
2873 InputGlue, GlueResultNodesMatched, true);
2880 case OPC_MarkGlueResults: {
2881 unsigned NumNodes = MatcherTable[MatcherIndex++];
2883 // Read and remember all the glue-result nodes.
2884 for (unsigned i = 0; i != NumNodes; ++i) {
2885 unsigned RecNo = MatcherTable[MatcherIndex++];
2887 RecNo = GetVBR(RecNo, MatcherTable, MatcherIndex);
2889 assert(RecNo < RecordedNodes.size() && "Invalid CheckSame");
2890 GlueResultNodesMatched.push_back(RecordedNodes[RecNo].first.getNode());
2895 case OPC_CompleteMatch: {
2896 // The match has been completed, and any new nodes (if any) have been
2897 // created. Patch up references to the matched dag to use the newly
2899 unsigned NumResults = MatcherTable[MatcherIndex++];
2901 for (unsigned i = 0; i != NumResults; ++i) {
2902 unsigned ResSlot = MatcherTable[MatcherIndex++];
2904 ResSlot = GetVBR(ResSlot, MatcherTable, MatcherIndex);
2906 assert(ResSlot < RecordedNodes.size() && "Invalid CheckSame");
2907 SDValue Res = RecordedNodes[ResSlot].first;
2909 assert(i < NodeToMatch->getNumValues() &&
2910 NodeToMatch->getValueType(i) != MVT::Other &&
2911 NodeToMatch->getValueType(i) != MVT::Glue &&
2912 "Invalid number of results to complete!");
2913 assert((NodeToMatch->getValueType(i) == Res.getValueType() ||
2914 NodeToMatch->getValueType(i) == MVT::iPTR ||
2915 Res.getValueType() == MVT::iPTR ||
2916 NodeToMatch->getValueType(i).getSizeInBits() ==
2917 Res.getValueType().getSizeInBits()) &&
2918 "invalid replacement");
2919 CurDAG->ReplaceAllUsesOfValueWith(SDValue(NodeToMatch, i), Res);
2922 // If the root node defines glue, add it to the glue nodes to update list.
2923 if (NodeToMatch->getValueType(NodeToMatch->getNumValues()-1) == MVT::Glue)
2924 GlueResultNodesMatched.push_back(NodeToMatch);
2926 // Update chain and glue uses.
2927 UpdateChainsAndGlue(NodeToMatch, InputChain, ChainNodesMatched,
2928 InputGlue, GlueResultNodesMatched, false);
2930 assert(NodeToMatch->use_empty() &&
2931 "Didn't replace all uses of the node?");
2933 // FIXME: We just return here, which interacts correctly with SelectRoot
2934 // above. We should fix this to not return an SDNode* anymore.
2939 // If the code reached this point, then the match failed. See if there is
2940 // another child to try in the current 'Scope', otherwise pop it until we
2941 // find a case to check.
2942 DEBUG(errs() << " Match failed at index " << CurrentOpcodeIndex << "\n");
2943 ++NumDAGIselRetries;
2945 if (MatchScopes.empty()) {
2946 CannotYetSelect(NodeToMatch);
2950 // Restore the interpreter state back to the point where the scope was
2952 MatchScope &LastScope = MatchScopes.back();
2953 RecordedNodes.resize(LastScope.NumRecordedNodes);
2955 NodeStack.append(LastScope.NodeStack.begin(), LastScope.NodeStack.end());
2956 N = NodeStack.back();
2958 if (LastScope.NumMatchedMemRefs != MatchedMemRefs.size())
2959 MatchedMemRefs.resize(LastScope.NumMatchedMemRefs);
2960 MatcherIndex = LastScope.FailIndex;
2962 DEBUG(errs() << " Continuing at " << MatcherIndex << "\n");
2964 InputChain = LastScope.InputChain;
2965 InputGlue = LastScope.InputGlue;
2966 if (!LastScope.HasChainNodesMatched)
2967 ChainNodesMatched.clear();
2968 if (!LastScope.HasGlueResultNodesMatched)
2969 GlueResultNodesMatched.clear();
2971 // Check to see what the offset is at the new MatcherIndex. If it is zero
2972 // we have reached the end of this scope, otherwise we have another child
2973 // in the current scope to try.
2974 unsigned NumToSkip = MatcherTable[MatcherIndex++];
2975 if (NumToSkip & 128)
2976 NumToSkip = GetVBR(NumToSkip, MatcherTable, MatcherIndex);
2978 // If we have another child in this scope to match, update FailIndex and
2980 if (NumToSkip != 0) {
2981 LastScope.FailIndex = MatcherIndex+NumToSkip;
2985 // End of this scope, pop it and try the next child in the containing
2987 MatchScopes.pop_back();
2994 void SelectionDAGISel::CannotYetSelect(SDNode *N) {
2996 raw_string_ostream Msg(msg);
2997 Msg << "Cannot select: ";
2999 if (N->getOpcode() != ISD::INTRINSIC_W_CHAIN &&
3000 N->getOpcode() != ISD::INTRINSIC_WO_CHAIN &&
3001 N->getOpcode() != ISD::INTRINSIC_VOID) {
3002 N->printrFull(Msg, CurDAG);
3003 Msg << "\nIn function: " << MF->getName();
3005 bool HasInputChain = N->getOperand(0).getValueType() == MVT::Other;
3007 cast<ConstantSDNode>(N->getOperand(HasInputChain))->getZExtValue();
3008 if (iid < Intrinsic::num_intrinsics)
3009 Msg << "intrinsic %" << Intrinsic::getName((Intrinsic::ID)iid);
3010 else if (const TargetIntrinsicInfo *TII = TM.getIntrinsicInfo())
3011 Msg << "target intrinsic %" << TII->getName(iid);
3013 Msg << "unknown intrinsic #" << iid;
3015 report_fatal_error(Msg.str());
3018 char SelectionDAGISel::ID = 0;