1 //===- InstCombineCalls.cpp -----------------------------------------------===//
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 file implements the visitCall and visitInvoke functions.
12 //===----------------------------------------------------------------------===//
14 #include "InstCombine.h"
15 #include "llvm/Support/CallSite.h"
16 #include "llvm/Target/TargetData.h"
17 #include "llvm/Analysis/MemoryBuiltins.h"
18 #include "llvm/Transforms/Utils/BuildLibCalls.h"
19 #include "llvm/Transforms/Utils/Local.h"
22 /// getPromotedType - Return the specified type promoted as it would be to pass
23 /// though a va_arg area.
24 static Type *getPromotedType(Type *Ty) {
25 if (IntegerType* ITy = dyn_cast<IntegerType>(Ty)) {
26 if (ITy->getBitWidth() < 32)
27 return Type::getInt32Ty(Ty->getContext());
33 Instruction *InstCombiner::SimplifyMemTransfer(MemIntrinsic *MI) {
34 unsigned DstAlign = getKnownAlignment(MI->getArgOperand(0), TD);
35 unsigned SrcAlign = getKnownAlignment(MI->getArgOperand(1), TD);
36 unsigned MinAlign = std::min(DstAlign, SrcAlign);
37 unsigned CopyAlign = MI->getAlignment();
39 if (CopyAlign < MinAlign) {
40 MI->setAlignment(ConstantInt::get(MI->getAlignmentType(),
45 // If MemCpyInst length is 1/2/4/8 bytes then replace memcpy with
47 ConstantInt *MemOpLength = dyn_cast<ConstantInt>(MI->getArgOperand(2));
48 if (MemOpLength == 0) return 0;
50 // Source and destination pointer types are always "i8*" for intrinsic. See
51 // if the size is something we can handle with a single primitive load/store.
52 // A single load+store correctly handles overlapping memory in the memmove
54 unsigned Size = MemOpLength->getZExtValue();
55 if (Size == 0) return MI; // Delete this mem transfer.
57 if (Size > 8 || (Size&(Size-1)))
58 return 0; // If not 1/2/4/8 bytes, exit.
60 // Use an integer load+store unless we can find something better.
62 cast<PointerType>(MI->getArgOperand(1)->getType())->getAddressSpace();
64 cast<PointerType>(MI->getArgOperand(0)->getType())->getAddressSpace();
66 IntegerType* IntType = IntegerType::get(MI->getContext(), Size<<3);
67 Type *NewSrcPtrTy = PointerType::get(IntType, SrcAddrSp);
68 Type *NewDstPtrTy = PointerType::get(IntType, DstAddrSp);
70 // Memcpy forces the use of i8* for the source and destination. That means
71 // that if you're using memcpy to move one double around, you'll get a cast
72 // from double* to i8*. We'd much rather use a double load+store rather than
73 // an i64 load+store, here because this improves the odds that the source or
74 // dest address will be promotable. See if we can find a better type than the
76 Value *StrippedDest = MI->getArgOperand(0)->stripPointerCasts();
77 if (StrippedDest != MI->getArgOperand(0)) {
78 Type *SrcETy = cast<PointerType>(StrippedDest->getType())
80 if (TD && SrcETy->isSized() && TD->getTypeStoreSize(SrcETy) == Size) {
81 // The SrcETy might be something like {{{double}}} or [1 x double]. Rip
82 // down through these levels if so.
83 while (!SrcETy->isSingleValueType()) {
84 if (StructType *STy = dyn_cast<StructType>(SrcETy)) {
85 if (STy->getNumElements() == 1)
86 SrcETy = STy->getElementType(0);
89 } else if (ArrayType *ATy = dyn_cast<ArrayType>(SrcETy)) {
90 if (ATy->getNumElements() == 1)
91 SrcETy = ATy->getElementType();
98 if (SrcETy->isSingleValueType()) {
99 NewSrcPtrTy = PointerType::get(SrcETy, SrcAddrSp);
100 NewDstPtrTy = PointerType::get(SrcETy, DstAddrSp);
106 // If the memcpy/memmove provides better alignment info than we can
108 SrcAlign = std::max(SrcAlign, CopyAlign);
109 DstAlign = std::max(DstAlign, CopyAlign);
111 Value *Src = Builder->CreateBitCast(MI->getArgOperand(1), NewSrcPtrTy);
112 Value *Dest = Builder->CreateBitCast(MI->getArgOperand(0), NewDstPtrTy);
113 LoadInst *L = Builder->CreateLoad(Src, MI->isVolatile());
114 L->setAlignment(SrcAlign);
115 StoreInst *S = Builder->CreateStore(L, Dest, MI->isVolatile());
116 S->setAlignment(DstAlign);
118 // Set the size of the copy to 0, it will be deleted on the next iteration.
119 MI->setArgOperand(2, Constant::getNullValue(MemOpLength->getType()));
123 Instruction *InstCombiner::SimplifyMemSet(MemSetInst *MI) {
124 unsigned Alignment = getKnownAlignment(MI->getDest(), TD);
125 if (MI->getAlignment() < Alignment) {
126 MI->setAlignment(ConstantInt::get(MI->getAlignmentType(),
131 // Extract the length and alignment and fill if they are constant.
132 ConstantInt *LenC = dyn_cast<ConstantInt>(MI->getLength());
133 ConstantInt *FillC = dyn_cast<ConstantInt>(MI->getValue());
134 if (!LenC || !FillC || !FillC->getType()->isIntegerTy(8))
136 uint64_t Len = LenC->getZExtValue();
137 Alignment = MI->getAlignment();
139 // If the length is zero, this is a no-op
140 if (Len == 0) return MI; // memset(d,c,0,a) -> noop
142 // memset(s,c,n) -> store s, c (for n=1,2,4,8)
143 if (Len <= 8 && isPowerOf2_32((uint32_t)Len)) {
144 Type *ITy = IntegerType::get(MI->getContext(), Len*8); // n=1 -> i8.
146 Value *Dest = MI->getDest();
147 unsigned DstAddrSp = cast<PointerType>(Dest->getType())->getAddressSpace();
148 Type *NewDstPtrTy = PointerType::get(ITy, DstAddrSp);
149 Dest = Builder->CreateBitCast(Dest, NewDstPtrTy);
151 // Alignment 0 is identity for alignment 1 for memset, but not store.
152 if (Alignment == 0) Alignment = 1;
154 // Extract the fill value and store.
155 uint64_t Fill = FillC->getZExtValue()*0x0101010101010101ULL;
156 StoreInst *S = Builder->CreateStore(ConstantInt::get(ITy, Fill), Dest,
158 S->setAlignment(Alignment);
160 // Set the size of the copy to 0, it will be deleted on the next iteration.
161 MI->setLength(Constant::getNullValue(LenC->getType()));
168 /// computeAllocSize - compute the object size allocated by an allocation
169 /// site. Returns 0 if the size is not constant (in SizeValue), 1 if the size
170 /// is constant (in Size), and 2 if the size could not be determined within the
171 /// given maximum Penalty that the computation would incurr at run-time.
172 static int computeAllocSize(Value *Alloc, uint64_t &Size, Value* &SizeValue,
173 uint64_t Penalty, TargetData *TD,
174 InstCombiner::BuilderTy *Builder) {
175 if (GlobalVariable *GV = dyn_cast<GlobalVariable>(Alloc)) {
176 if (GV->hasUniqueInitializer()) {
177 Constant *C = GV->getInitializer();
178 Size = TD->getTypeAllocSize(C->getType());
181 // Can't determine size of the GV.
184 } else if (AllocaInst *AI = dyn_cast<AllocaInst>(Alloc)) {
185 if (!AI->getAllocatedType()->isSized())
188 Size = TD->getTypeAllocSize(AI->getAllocatedType());
189 if (!AI->isArrayAllocation())
190 return 1; // we are done
192 Value *ArraySize = AI->getArraySize();
193 if (const ConstantInt *C = dyn_cast<ConstantInt>(ArraySize)) {
194 Size *= C->getZExtValue();
201 SizeValue = Builder->CreateMul(Builder->getInt64(Size), ArraySize);
204 } else if (CallInst *MI = extractMallocCall(Alloc)) {
205 SizeValue = MI->getArgOperand(0);
206 if (ConstantInt *CI = dyn_cast<ConstantInt>(SizeValue)) {
207 Size = CI->getZExtValue();
212 } else if (CallInst *MI = extractCallocCall(Alloc)) {
213 Value *Arg1 = MI->getArgOperand(0);
214 Value *Arg2 = MI->getArgOperand(1);
215 if (ConstantInt *CI1 = dyn_cast<ConstantInt>(Arg1)) {
216 if (ConstantInt *CI2 = dyn_cast<ConstantInt>(Arg2)) {
217 Size = (CI1->getValue() * CI2->getValue()).getZExtValue();
225 SizeValue = Builder->CreateMul(Arg1, Arg2);
229 DEBUG(errs() << "computeAllocSize failed:\n");
230 DEBUG(Alloc->dump());
234 /// visitCallInst - CallInst simplification. This mostly only handles folding
235 /// of intrinsic instructions. For normal calls, it allows visitCallSite to do
236 /// the heavy lifting.
238 Instruction *InstCombiner::visitCallInst(CallInst &CI) {
240 return visitFree(CI);
241 if (extractMallocCall(&CI) || extractCallocCall(&CI))
242 return visitMalloc(CI);
244 // If the caller function is nounwind, mark the call as nounwind, even if the
246 if (CI.getParent()->getParent()->doesNotThrow() &&
247 !CI.doesNotThrow()) {
248 CI.setDoesNotThrow();
252 IntrinsicInst *II = dyn_cast<IntrinsicInst>(&CI);
253 if (!II) return visitCallSite(&CI);
255 // Intrinsics cannot occur in an invoke, so handle them here instead of in
257 if (MemIntrinsic *MI = dyn_cast<MemIntrinsic>(II)) {
258 bool Changed = false;
260 // memmove/cpy/set of zero bytes is a noop.
261 if (Constant *NumBytes = dyn_cast<Constant>(MI->getLength())) {
262 if (NumBytes->isNullValue())
263 return EraseInstFromFunction(CI);
265 if (ConstantInt *CI = dyn_cast<ConstantInt>(NumBytes))
266 if (CI->getZExtValue() == 1) {
267 // Replace the instruction with just byte operations. We would
268 // transform other cases to loads/stores, but we don't know if
269 // alignment is sufficient.
273 // No other transformations apply to volatile transfers.
274 if (MI->isVolatile())
277 // If we have a memmove and the source operation is a constant global,
278 // then the source and dest pointers can't alias, so we can change this
279 // into a call to memcpy.
280 if (MemMoveInst *MMI = dyn_cast<MemMoveInst>(MI)) {
281 if (GlobalVariable *GVSrc = dyn_cast<GlobalVariable>(MMI->getSource()))
282 if (GVSrc->isConstant()) {
283 Module *M = CI.getParent()->getParent()->getParent();
284 Intrinsic::ID MemCpyID = Intrinsic::memcpy;
285 Type *Tys[3] = { CI.getArgOperand(0)->getType(),
286 CI.getArgOperand(1)->getType(),
287 CI.getArgOperand(2)->getType() };
288 CI.setCalledFunction(Intrinsic::getDeclaration(M, MemCpyID, Tys));
293 if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(MI)) {
294 // memmove(x,x,size) -> noop.
295 if (MTI->getSource() == MTI->getDest())
296 return EraseInstFromFunction(CI);
299 // If we can determine a pointer alignment that is bigger than currently
300 // set, update the alignment.
301 if (isa<MemTransferInst>(MI)) {
302 if (Instruction *I = SimplifyMemTransfer(MI))
304 } else if (MemSetInst *MSI = dyn_cast<MemSetInst>(MI)) {
305 if (Instruction *I = SimplifyMemSet(MSI))
309 if (Changed) return II;
312 switch (II->getIntrinsicID()) {
314 case Intrinsic::objectsize: {
315 // We need target data for just about everything so depend on it.
318 Type *ReturnTy = CI.getType();
319 uint64_t Penalty = cast<ConstantInt>(II->getArgOperand(2))->getZExtValue();
321 // Get to the real allocated thing and offset as fast as possible.
322 Value *Op1 = II->getArgOperand(0)->stripPointerCasts();
326 bool ConstOffset = true;
328 // Try to look through constant GEPs.
329 if (GEPOperator *GEP = dyn_cast<GEPOperator>(Op1)) {
330 if (!GEP->hasAllConstantIndices()) return 0;
332 // Get the current byte offset into the thing. Use the original
333 // operand in case we're looking through a bitcast.
334 SmallVector<Value*, 8> Ops(GEP->idx_begin(), GEP->idx_end());
335 if (!GEP->getPointerOperandType()->isPointerTy())
337 Offset = TD->getIndexedOffset(GEP->getPointerOperandType(), Ops);
339 Op1 = GEP->getPointerOperand()->stripPointerCasts();
344 int ConstAlloc = computeAllocSize(Op1, Size, SizeValue, Penalty, TD,
347 // Do not return "I don't know" here. Later optimization passes could
348 // make it possible to evaluate objectsize to a constant.
352 if (ConstOffset && ConstAlloc) {
355 return ReplaceInstUsesWith(CI, ConstantInt::get(ReturnTy, 0));
357 return ReplaceInstUsesWith(CI, ConstantInt::get(ReturnTy, Size-Offset));
359 } else if (Penalty >= 2) {
361 OffsetValue = Builder->getInt64(Offset);
363 SizeValue = Builder->getInt64(Size);
365 Value *Val = Builder->CreateSub(SizeValue, OffsetValue);
366 Val = Builder->CreateTrunc(Val, ReturnTy);
367 // return 0 if there's an overflow
368 Value *Cmp = Builder->CreateICmpULT(SizeValue, OffsetValue);
369 Val = Builder->CreateSelect(Cmp, ConstantInt::get(ReturnTy, 0), Val);
370 return ReplaceInstUsesWith(CI, Val);
375 case Intrinsic::bswap:
376 // bswap(bswap(x)) -> x
377 if (IntrinsicInst *Operand = dyn_cast<IntrinsicInst>(II->getArgOperand(0)))
378 if (Operand->getIntrinsicID() == Intrinsic::bswap)
379 return ReplaceInstUsesWith(CI, Operand->getArgOperand(0));
381 // bswap(trunc(bswap(x))) -> trunc(lshr(x, c))
382 if (TruncInst *TI = dyn_cast<TruncInst>(II->getArgOperand(0))) {
383 if (IntrinsicInst *Operand = dyn_cast<IntrinsicInst>(TI->getOperand(0)))
384 if (Operand->getIntrinsicID() == Intrinsic::bswap) {
385 unsigned C = Operand->getType()->getPrimitiveSizeInBits() -
386 TI->getType()->getPrimitiveSizeInBits();
387 Value *CV = ConstantInt::get(Operand->getType(), C);
388 Value *V = Builder->CreateLShr(Operand->getArgOperand(0), CV);
389 return new TruncInst(V, TI->getType());
394 case Intrinsic::powi:
395 if (ConstantInt *Power = dyn_cast<ConstantInt>(II->getArgOperand(1))) {
398 return ReplaceInstUsesWith(CI, ConstantFP::get(CI.getType(), 1.0));
401 return ReplaceInstUsesWith(CI, II->getArgOperand(0));
402 // powi(x, -1) -> 1/x
403 if (Power->isAllOnesValue())
404 return BinaryOperator::CreateFDiv(ConstantFP::get(CI.getType(), 1.0),
405 II->getArgOperand(0));
408 case Intrinsic::cttz: {
409 // If all bits below the first known one are known zero,
410 // this value is constant.
411 IntegerType *IT = dyn_cast<IntegerType>(II->getArgOperand(0)->getType());
412 // FIXME: Try to simplify vectors of integers.
414 uint32_t BitWidth = IT->getBitWidth();
415 APInt KnownZero(BitWidth, 0);
416 APInt KnownOne(BitWidth, 0);
417 ComputeMaskedBits(II->getArgOperand(0), KnownZero, KnownOne);
418 unsigned TrailingZeros = KnownOne.countTrailingZeros();
419 APInt Mask(APInt::getLowBitsSet(BitWidth, TrailingZeros));
420 if ((Mask & KnownZero) == Mask)
421 return ReplaceInstUsesWith(CI, ConstantInt::get(IT,
422 APInt(BitWidth, TrailingZeros)));
426 case Intrinsic::ctlz: {
427 // If all bits above the first known one are known zero,
428 // this value is constant.
429 IntegerType *IT = dyn_cast<IntegerType>(II->getArgOperand(0)->getType());
430 // FIXME: Try to simplify vectors of integers.
432 uint32_t BitWidth = IT->getBitWidth();
433 APInt KnownZero(BitWidth, 0);
434 APInt KnownOne(BitWidth, 0);
435 ComputeMaskedBits(II->getArgOperand(0), KnownZero, KnownOne);
436 unsigned LeadingZeros = KnownOne.countLeadingZeros();
437 APInt Mask(APInt::getHighBitsSet(BitWidth, LeadingZeros));
438 if ((Mask & KnownZero) == Mask)
439 return ReplaceInstUsesWith(CI, ConstantInt::get(IT,
440 APInt(BitWidth, LeadingZeros)));
444 case Intrinsic::uadd_with_overflow: {
445 Value *LHS = II->getArgOperand(0), *RHS = II->getArgOperand(1);
446 IntegerType *IT = cast<IntegerType>(II->getArgOperand(0)->getType());
447 uint32_t BitWidth = IT->getBitWidth();
448 APInt LHSKnownZero(BitWidth, 0);
449 APInt LHSKnownOne(BitWidth, 0);
450 ComputeMaskedBits(LHS, LHSKnownZero, LHSKnownOne);
451 bool LHSKnownNegative = LHSKnownOne[BitWidth - 1];
452 bool LHSKnownPositive = LHSKnownZero[BitWidth - 1];
454 if (LHSKnownNegative || LHSKnownPositive) {
455 APInt RHSKnownZero(BitWidth, 0);
456 APInt RHSKnownOne(BitWidth, 0);
457 ComputeMaskedBits(RHS, RHSKnownZero, RHSKnownOne);
458 bool RHSKnownNegative = RHSKnownOne[BitWidth - 1];
459 bool RHSKnownPositive = RHSKnownZero[BitWidth - 1];
460 if (LHSKnownNegative && RHSKnownNegative) {
461 // The sign bit is set in both cases: this MUST overflow.
462 // Create a simple add instruction, and insert it into the struct.
463 Value *Add = Builder->CreateAdd(LHS, RHS);
466 UndefValue::get(LHS->getType()),
467 ConstantInt::getTrue(II->getContext())
469 StructType *ST = cast<StructType>(II->getType());
470 Constant *Struct = ConstantStruct::get(ST, V);
471 return InsertValueInst::Create(Struct, Add, 0);
474 if (LHSKnownPositive && RHSKnownPositive) {
475 // The sign bit is clear in both cases: this CANNOT overflow.
476 // Create a simple add instruction, and insert it into the struct.
477 Value *Add = Builder->CreateNUWAdd(LHS, RHS);
480 UndefValue::get(LHS->getType()),
481 ConstantInt::getFalse(II->getContext())
483 StructType *ST = cast<StructType>(II->getType());
484 Constant *Struct = ConstantStruct::get(ST, V);
485 return InsertValueInst::Create(Struct, Add, 0);
489 // FALL THROUGH uadd into sadd
490 case Intrinsic::sadd_with_overflow:
491 // Canonicalize constants into the RHS.
492 if (isa<Constant>(II->getArgOperand(0)) &&
493 !isa<Constant>(II->getArgOperand(1))) {
494 Value *LHS = II->getArgOperand(0);
495 II->setArgOperand(0, II->getArgOperand(1));
496 II->setArgOperand(1, LHS);
500 // X + undef -> undef
501 if (isa<UndefValue>(II->getArgOperand(1)))
502 return ReplaceInstUsesWith(CI, UndefValue::get(II->getType()));
504 if (ConstantInt *RHS = dyn_cast<ConstantInt>(II->getArgOperand(1))) {
505 // X + 0 -> {X, false}
508 UndefValue::get(II->getArgOperand(0)->getType()),
509 ConstantInt::getFalse(II->getContext())
512 ConstantStruct::get(cast<StructType>(II->getType()), V);
513 return InsertValueInst::Create(Struct, II->getArgOperand(0), 0);
517 case Intrinsic::usub_with_overflow:
518 case Intrinsic::ssub_with_overflow:
519 // undef - X -> undef
520 // X - undef -> undef
521 if (isa<UndefValue>(II->getArgOperand(0)) ||
522 isa<UndefValue>(II->getArgOperand(1)))
523 return ReplaceInstUsesWith(CI, UndefValue::get(II->getType()));
525 if (ConstantInt *RHS = dyn_cast<ConstantInt>(II->getArgOperand(1))) {
526 // X - 0 -> {X, false}
529 UndefValue::get(II->getArgOperand(0)->getType()),
530 ConstantInt::getFalse(II->getContext())
533 ConstantStruct::get(cast<StructType>(II->getType()), V);
534 return InsertValueInst::Create(Struct, II->getArgOperand(0), 0);
538 case Intrinsic::umul_with_overflow: {
539 Value *LHS = II->getArgOperand(0), *RHS = II->getArgOperand(1);
540 unsigned BitWidth = cast<IntegerType>(LHS->getType())->getBitWidth();
542 APInt LHSKnownZero(BitWidth, 0);
543 APInt LHSKnownOne(BitWidth, 0);
544 ComputeMaskedBits(LHS, LHSKnownZero, LHSKnownOne);
545 APInt RHSKnownZero(BitWidth, 0);
546 APInt RHSKnownOne(BitWidth, 0);
547 ComputeMaskedBits(RHS, RHSKnownZero, RHSKnownOne);
549 // Get the largest possible values for each operand.
550 APInt LHSMax = ~LHSKnownZero;
551 APInt RHSMax = ~RHSKnownZero;
553 // If multiplying the maximum values does not overflow then we can turn
554 // this into a plain NUW mul.
556 LHSMax.umul_ov(RHSMax, Overflow);
558 Value *Mul = Builder->CreateNUWMul(LHS, RHS, "umul_with_overflow");
560 UndefValue::get(LHS->getType()),
563 Constant *Struct = ConstantStruct::get(cast<StructType>(II->getType()),V);
564 return InsertValueInst::Create(Struct, Mul, 0);
567 case Intrinsic::smul_with_overflow:
568 // Canonicalize constants into the RHS.
569 if (isa<Constant>(II->getArgOperand(0)) &&
570 !isa<Constant>(II->getArgOperand(1))) {
571 Value *LHS = II->getArgOperand(0);
572 II->setArgOperand(0, II->getArgOperand(1));
573 II->setArgOperand(1, LHS);
577 // X * undef -> undef
578 if (isa<UndefValue>(II->getArgOperand(1)))
579 return ReplaceInstUsesWith(CI, UndefValue::get(II->getType()));
581 if (ConstantInt *RHSI = dyn_cast<ConstantInt>(II->getArgOperand(1))) {
584 return ReplaceInstUsesWith(CI, Constant::getNullValue(II->getType()));
586 // X * 1 -> {X, false}
587 if (RHSI->equalsInt(1)) {
589 UndefValue::get(II->getArgOperand(0)->getType()),
590 ConstantInt::getFalse(II->getContext())
593 ConstantStruct::get(cast<StructType>(II->getType()), V);
594 return InsertValueInst::Create(Struct, II->getArgOperand(0), 0);
598 case Intrinsic::ppc_altivec_lvx:
599 case Intrinsic::ppc_altivec_lvxl:
600 // Turn PPC lvx -> load if the pointer is known aligned.
601 if (getOrEnforceKnownAlignment(II->getArgOperand(0), 16, TD) >= 16) {
602 Value *Ptr = Builder->CreateBitCast(II->getArgOperand(0),
603 PointerType::getUnqual(II->getType()));
604 return new LoadInst(Ptr);
607 case Intrinsic::ppc_altivec_stvx:
608 case Intrinsic::ppc_altivec_stvxl:
609 // Turn stvx -> store if the pointer is known aligned.
610 if (getOrEnforceKnownAlignment(II->getArgOperand(1), 16, TD) >= 16) {
612 PointerType::getUnqual(II->getArgOperand(0)->getType());
613 Value *Ptr = Builder->CreateBitCast(II->getArgOperand(1), OpPtrTy);
614 return new StoreInst(II->getArgOperand(0), Ptr);
617 case Intrinsic::x86_sse_storeu_ps:
618 case Intrinsic::x86_sse2_storeu_pd:
619 case Intrinsic::x86_sse2_storeu_dq:
620 // Turn X86 storeu -> store if the pointer is known aligned.
621 if (getOrEnforceKnownAlignment(II->getArgOperand(0), 16, TD) >= 16) {
623 PointerType::getUnqual(II->getArgOperand(1)->getType());
624 Value *Ptr = Builder->CreateBitCast(II->getArgOperand(0), OpPtrTy);
625 return new StoreInst(II->getArgOperand(1), Ptr);
629 case Intrinsic::x86_sse_cvtss2si:
630 case Intrinsic::x86_sse_cvtss2si64:
631 case Intrinsic::x86_sse_cvttss2si:
632 case Intrinsic::x86_sse_cvttss2si64:
633 case Intrinsic::x86_sse2_cvtsd2si:
634 case Intrinsic::x86_sse2_cvtsd2si64:
635 case Intrinsic::x86_sse2_cvttsd2si:
636 case Intrinsic::x86_sse2_cvttsd2si64: {
637 // These intrinsics only demand the 0th element of their input vectors. If
638 // we can simplify the input based on that, do so now.
640 cast<VectorType>(II->getArgOperand(0)->getType())->getNumElements();
641 APInt DemandedElts(VWidth, 1);
642 APInt UndefElts(VWidth, 0);
643 if (Value *V = SimplifyDemandedVectorElts(II->getArgOperand(0),
644 DemandedElts, UndefElts)) {
645 II->setArgOperand(0, V);
652 case Intrinsic::x86_sse41_pmovsxbw:
653 case Intrinsic::x86_sse41_pmovsxwd:
654 case Intrinsic::x86_sse41_pmovsxdq:
655 case Intrinsic::x86_sse41_pmovzxbw:
656 case Intrinsic::x86_sse41_pmovzxwd:
657 case Intrinsic::x86_sse41_pmovzxdq: {
658 // pmov{s|z}x ignores the upper half of their input vectors.
660 cast<VectorType>(II->getArgOperand(0)->getType())->getNumElements();
661 unsigned LowHalfElts = VWidth / 2;
662 APInt InputDemandedElts(APInt::getBitsSet(VWidth, 0, LowHalfElts));
663 APInt UndefElts(VWidth, 0);
664 if (Value *TmpV = SimplifyDemandedVectorElts(II->getArgOperand(0),
667 II->setArgOperand(0, TmpV);
673 case Intrinsic::ppc_altivec_vperm:
674 // Turn vperm(V1,V2,mask) -> shuffle(V1,V2,mask) if mask is a constant.
675 if (Constant *Mask = dyn_cast<Constant>(II->getArgOperand(2))) {
676 assert(Mask->getType()->getVectorNumElements() == 16 &&
677 "Bad type for intrinsic!");
679 // Check that all of the elements are integer constants or undefs.
680 bool AllEltsOk = true;
681 for (unsigned i = 0; i != 16; ++i) {
682 Constant *Elt = Mask->getAggregateElement(i);
684 !(isa<ConstantInt>(Elt) || isa<UndefValue>(Elt))) {
691 // Cast the input vectors to byte vectors.
692 Value *Op0 = Builder->CreateBitCast(II->getArgOperand(0),
694 Value *Op1 = Builder->CreateBitCast(II->getArgOperand(1),
696 Value *Result = UndefValue::get(Op0->getType());
698 // Only extract each element once.
699 Value *ExtractedElts[32];
700 memset(ExtractedElts, 0, sizeof(ExtractedElts));
702 for (unsigned i = 0; i != 16; ++i) {
703 if (isa<UndefValue>(Mask->getAggregateElement(i)))
706 cast<ConstantInt>(Mask->getAggregateElement(i))->getZExtValue();
707 Idx &= 31; // Match the hardware behavior.
709 if (ExtractedElts[Idx] == 0) {
711 Builder->CreateExtractElement(Idx < 16 ? Op0 : Op1,
712 Builder->getInt32(Idx&15));
715 // Insert this value into the result vector.
716 Result = Builder->CreateInsertElement(Result, ExtractedElts[Idx],
717 Builder->getInt32(i));
719 return CastInst::Create(Instruction::BitCast, Result, CI.getType());
724 case Intrinsic::arm_neon_vld1:
725 case Intrinsic::arm_neon_vld2:
726 case Intrinsic::arm_neon_vld3:
727 case Intrinsic::arm_neon_vld4:
728 case Intrinsic::arm_neon_vld2lane:
729 case Intrinsic::arm_neon_vld3lane:
730 case Intrinsic::arm_neon_vld4lane:
731 case Intrinsic::arm_neon_vst1:
732 case Intrinsic::arm_neon_vst2:
733 case Intrinsic::arm_neon_vst3:
734 case Intrinsic::arm_neon_vst4:
735 case Intrinsic::arm_neon_vst2lane:
736 case Intrinsic::arm_neon_vst3lane:
737 case Intrinsic::arm_neon_vst4lane: {
738 unsigned MemAlign = getKnownAlignment(II->getArgOperand(0), TD);
739 unsigned AlignArg = II->getNumArgOperands() - 1;
740 ConstantInt *IntrAlign = dyn_cast<ConstantInt>(II->getArgOperand(AlignArg));
741 if (IntrAlign && IntrAlign->getZExtValue() < MemAlign) {
742 II->setArgOperand(AlignArg,
743 ConstantInt::get(Type::getInt32Ty(II->getContext()),
750 case Intrinsic::arm_neon_vmulls:
751 case Intrinsic::arm_neon_vmullu: {
752 Value *Arg0 = II->getArgOperand(0);
753 Value *Arg1 = II->getArgOperand(1);
755 // Handle mul by zero first:
756 if (isa<ConstantAggregateZero>(Arg0) || isa<ConstantAggregateZero>(Arg1)) {
757 return ReplaceInstUsesWith(CI, ConstantAggregateZero::get(II->getType()));
760 // Check for constant LHS & RHS - in this case we just simplify.
761 bool Zext = (II->getIntrinsicID() == Intrinsic::arm_neon_vmullu);
762 VectorType *NewVT = cast<VectorType>(II->getType());
763 unsigned NewWidth = NewVT->getElementType()->getIntegerBitWidth();
764 if (ConstantDataVector *CV0 = dyn_cast<ConstantDataVector>(Arg0)) {
765 if (ConstantDataVector *CV1 = dyn_cast<ConstantDataVector>(Arg1)) {
766 VectorType* VT = cast<VectorType>(CV0->getType());
767 SmallVector<Constant*, 4> NewElems;
768 for (unsigned i = 0; i < VT->getNumElements(); ++i) {
770 (cast<ConstantInt>(CV0->getAggregateElement(i)))->getValue();
771 CV0E = Zext ? CV0E.zext(NewWidth) : CV0E.sext(NewWidth);
773 (cast<ConstantInt>(CV1->getAggregateElement(i)))->getValue();
774 CV1E = Zext ? CV1E.zext(NewWidth) : CV1E.sext(NewWidth);
776 ConstantInt::get(NewVT->getElementType(), CV0E * CV1E));
778 return ReplaceInstUsesWith(CI, ConstantVector::get(NewElems));
781 // Couldn't simplify - cannonicalize constant to the RHS.
782 std::swap(Arg0, Arg1);
785 // Handle mul by one:
786 if (ConstantDataVector *CV1 = dyn_cast<ConstantDataVector>(Arg1)) {
787 if (ConstantInt *Splat =
788 dyn_cast_or_null<ConstantInt>(CV1->getSplatValue())) {
789 if (Splat->isOne()) {
791 return CastInst::CreateZExtOrBitCast(Arg0, II->getType());
793 return CastInst::CreateSExtOrBitCast(Arg0, II->getType());
801 case Intrinsic::stackrestore: {
802 // If the save is right next to the restore, remove the restore. This can
803 // happen when variable allocas are DCE'd.
804 if (IntrinsicInst *SS = dyn_cast<IntrinsicInst>(II->getArgOperand(0))) {
805 if (SS->getIntrinsicID() == Intrinsic::stacksave) {
806 BasicBlock::iterator BI = SS;
808 return EraseInstFromFunction(CI);
812 // Scan down this block to see if there is another stack restore in the
813 // same block without an intervening call/alloca.
814 BasicBlock::iterator BI = II;
815 TerminatorInst *TI = II->getParent()->getTerminator();
816 bool CannotRemove = false;
817 for (++BI; &*BI != TI; ++BI) {
818 if (isa<AllocaInst>(BI) || isMalloc(BI)) {
822 if (CallInst *BCI = dyn_cast<CallInst>(BI)) {
823 if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(BCI)) {
824 // If there is a stackrestore below this one, remove this one.
825 if (II->getIntrinsicID() == Intrinsic::stackrestore)
826 return EraseInstFromFunction(CI);
827 // Otherwise, ignore the intrinsic.
829 // If we found a non-intrinsic call, we can't remove the stack
837 // If the stack restore is in a return, resume, or unwind block and if there
838 // are no allocas or calls between the restore and the return, nuke the
840 if (!CannotRemove && (isa<ReturnInst>(TI) || isa<ResumeInst>(TI)))
841 return EraseInstFromFunction(CI);
846 return visitCallSite(II);
849 // InvokeInst simplification
851 Instruction *InstCombiner::visitInvokeInst(InvokeInst &II) {
852 return visitCallSite(&II);
855 /// isSafeToEliminateVarargsCast - If this cast does not affect the value
856 /// passed through the varargs area, we can eliminate the use of the cast.
857 static bool isSafeToEliminateVarargsCast(const CallSite CS,
858 const CastInst * const CI,
859 const TargetData * const TD,
861 if (!CI->isLosslessCast())
864 // The size of ByVal arguments is derived from the type, so we
865 // can't change to a type with a different size. If the size were
866 // passed explicitly we could avoid this check.
867 if (!CS.isByValArgument(ix))
871 cast<PointerType>(CI->getOperand(0)->getType())->getElementType();
872 Type* DstTy = cast<PointerType>(CI->getType())->getElementType();
873 if (!SrcTy->isSized() || !DstTy->isSized())
875 if (!TD || TD->getTypeAllocSize(SrcTy) != TD->getTypeAllocSize(DstTy))
881 class InstCombineFortifiedLibCalls : public SimplifyFortifiedLibCalls {
884 void replaceCall(Value *With) {
885 NewInstruction = IC->ReplaceInstUsesWith(*CI, With);
887 bool isFoldable(unsigned SizeCIOp, unsigned SizeArgOp, bool isString) const {
888 if (CI->getArgOperand(SizeCIOp) == CI->getArgOperand(SizeArgOp))
890 if (ConstantInt *SizeCI =
891 dyn_cast<ConstantInt>(CI->getArgOperand(SizeCIOp))) {
892 if (SizeCI->isAllOnesValue())
895 uint64_t Len = GetStringLength(CI->getArgOperand(SizeArgOp));
896 // If the length is 0 we don't know how long it is and so we can't
898 if (Len == 0) return false;
899 return SizeCI->getZExtValue() >= Len;
901 if (ConstantInt *Arg = dyn_cast<ConstantInt>(
902 CI->getArgOperand(SizeArgOp)))
903 return SizeCI->getZExtValue() >= Arg->getZExtValue();
908 InstCombineFortifiedLibCalls(InstCombiner *IC) : IC(IC), NewInstruction(0) { }
909 Instruction *NewInstruction;
911 } // end anonymous namespace
913 // Try to fold some different type of calls here.
914 // Currently we're only working with the checking functions, memcpy_chk,
915 // mempcpy_chk, memmove_chk, memset_chk, strcpy_chk, stpcpy_chk, strncpy_chk,
916 // strcat_chk and strncat_chk.
917 Instruction *InstCombiner::tryOptimizeCall(CallInst *CI, const TargetData *TD) {
918 if (CI->getCalledFunction() == 0) return 0;
920 InstCombineFortifiedLibCalls Simplifier(this);
921 Simplifier.fold(CI, TD);
922 return Simplifier.NewInstruction;
925 static IntrinsicInst *FindInitTrampolineFromAlloca(Value *TrampMem) {
926 // Strip off at most one level of pointer casts, looking for an alloca. This
927 // is good enough in practice and simpler than handling any number of casts.
928 Value *Underlying = TrampMem->stripPointerCasts();
929 if (Underlying != TrampMem &&
930 (!Underlying->hasOneUse() || *Underlying->use_begin() != TrampMem))
932 if (!isa<AllocaInst>(Underlying))
935 IntrinsicInst *InitTrampoline = 0;
936 for (Value::use_iterator I = TrampMem->use_begin(), E = TrampMem->use_end();
938 IntrinsicInst *II = dyn_cast<IntrinsicInst>(*I);
941 if (II->getIntrinsicID() == Intrinsic::init_trampoline) {
943 // More than one init_trampoline writes to this value. Give up.
948 if (II->getIntrinsicID() == Intrinsic::adjust_trampoline)
949 // Allow any number of calls to adjust.trampoline.
954 // No call to init.trampoline found.
958 // Check that the alloca is being used in the expected way.
959 if (InitTrampoline->getOperand(0) != TrampMem)
962 return InitTrampoline;
965 static IntrinsicInst *FindInitTrampolineFromBB(IntrinsicInst *AdjustTramp,
967 // Visit all the previous instructions in the basic block, and try to find a
968 // init.trampoline which has a direct path to the adjust.trampoline.
969 for (BasicBlock::iterator I = AdjustTramp,
970 E = AdjustTramp->getParent()->begin(); I != E; ) {
971 Instruction *Inst = --I;
972 if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I))
973 if (II->getIntrinsicID() == Intrinsic::init_trampoline &&
974 II->getOperand(0) == TrampMem)
976 if (Inst->mayWriteToMemory())
982 // Given a call to llvm.adjust.trampoline, find and return the corresponding
983 // call to llvm.init.trampoline if the call to the trampoline can be optimized
984 // to a direct call to a function. Otherwise return NULL.
986 static IntrinsicInst *FindInitTrampoline(Value *Callee) {
987 Callee = Callee->stripPointerCasts();
988 IntrinsicInst *AdjustTramp = dyn_cast<IntrinsicInst>(Callee);
990 AdjustTramp->getIntrinsicID() != Intrinsic::adjust_trampoline)
993 Value *TrampMem = AdjustTramp->getOperand(0);
995 if (IntrinsicInst *IT = FindInitTrampolineFromAlloca(TrampMem))
997 if (IntrinsicInst *IT = FindInitTrampolineFromBB(AdjustTramp, TrampMem))
1002 // visitCallSite - Improvements for call and invoke instructions.
1004 Instruction *InstCombiner::visitCallSite(CallSite CS) {
1005 bool Changed = false;
1007 // If the callee is a pointer to a function, attempt to move any casts to the
1008 // arguments of the call/invoke.
1009 Value *Callee = CS.getCalledValue();
1010 if (!isa<Function>(Callee) && transformConstExprCastCall(CS))
1013 if (Function *CalleeF = dyn_cast<Function>(Callee))
1014 // If the call and callee calling conventions don't match, this call must
1015 // be unreachable, as the call is undefined.
1016 if (CalleeF->getCallingConv() != CS.getCallingConv() &&
1017 // Only do this for calls to a function with a body. A prototype may
1018 // not actually end up matching the implementation's calling conv for a
1019 // variety of reasons (e.g. it may be written in assembly).
1020 !CalleeF->isDeclaration()) {
1021 Instruction *OldCall = CS.getInstruction();
1022 new StoreInst(ConstantInt::getTrue(Callee->getContext()),
1023 UndefValue::get(Type::getInt1PtrTy(Callee->getContext())),
1025 // If OldCall dues not return void then replaceAllUsesWith undef.
1026 // This allows ValueHandlers and custom metadata to adjust itself.
1027 if (!OldCall->getType()->isVoidTy())
1028 ReplaceInstUsesWith(*OldCall, UndefValue::get(OldCall->getType()));
1029 if (isa<CallInst>(OldCall))
1030 return EraseInstFromFunction(*OldCall);
1032 // We cannot remove an invoke, because it would change the CFG, just
1033 // change the callee to a null pointer.
1034 cast<InvokeInst>(OldCall)->setCalledFunction(
1035 Constant::getNullValue(CalleeF->getType()));
1039 if (isa<ConstantPointerNull>(Callee) || isa<UndefValue>(Callee)) {
1040 // This instruction is not reachable, just remove it. We insert a store to
1041 // undef so that we know that this code is not reachable, despite the fact
1042 // that we can't modify the CFG here.
1043 new StoreInst(ConstantInt::getTrue(Callee->getContext()),
1044 UndefValue::get(Type::getInt1PtrTy(Callee->getContext())),
1045 CS.getInstruction());
1047 // If CS does not return void then replaceAllUsesWith undef.
1048 // This allows ValueHandlers and custom metadata to adjust itself.
1049 if (!CS.getInstruction()->getType()->isVoidTy())
1050 ReplaceInstUsesWith(*CS.getInstruction(),
1051 UndefValue::get(CS.getInstruction()->getType()));
1053 if (InvokeInst *II = dyn_cast<InvokeInst>(CS.getInstruction())) {
1054 // Don't break the CFG, insert a dummy cond branch.
1055 BranchInst::Create(II->getNormalDest(), II->getUnwindDest(),
1056 ConstantInt::getTrue(Callee->getContext()), II);
1058 return EraseInstFromFunction(*CS.getInstruction());
1061 if (IntrinsicInst *II = FindInitTrampoline(Callee))
1062 return transformCallThroughTrampoline(CS, II);
1064 PointerType *PTy = cast<PointerType>(Callee->getType());
1065 FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1066 if (FTy->isVarArg()) {
1067 int ix = FTy->getNumParams();
1068 // See if we can optimize any arguments passed through the varargs area of
1070 for (CallSite::arg_iterator I = CS.arg_begin()+FTy->getNumParams(),
1071 E = CS.arg_end(); I != E; ++I, ++ix) {
1072 CastInst *CI = dyn_cast<CastInst>(*I);
1073 if (CI && isSafeToEliminateVarargsCast(CS, CI, TD, ix)) {
1074 *I = CI->getOperand(0);
1080 if (isa<InlineAsm>(Callee) && !CS.doesNotThrow()) {
1081 // Inline asm calls cannot throw - mark them 'nounwind'.
1082 CS.setDoesNotThrow();
1086 // Try to optimize the call if possible, we require TargetData for most of
1087 // this. None of these calls are seen as possibly dead so go ahead and
1088 // delete the instruction now.
1089 if (CallInst *CI = dyn_cast<CallInst>(CS.getInstruction())) {
1090 Instruction *I = tryOptimizeCall(CI, TD);
1091 // If we changed something return the result, etc. Otherwise let
1092 // the fallthrough check.
1093 if (I) return EraseInstFromFunction(*I);
1096 return Changed ? CS.getInstruction() : 0;
1099 // transformConstExprCastCall - If the callee is a constexpr cast of a function,
1100 // attempt to move the cast to the arguments of the call/invoke.
1102 bool InstCombiner::transformConstExprCastCall(CallSite CS) {
1104 dyn_cast<Function>(CS.getCalledValue()->stripPointerCasts());
1107 Instruction *Caller = CS.getInstruction();
1108 const AttrListPtr &CallerPAL = CS.getAttributes();
1110 // Okay, this is a cast from a function to a different type. Unless doing so
1111 // would cause a type conversion of one of our arguments, change this call to
1112 // be a direct call with arguments casted to the appropriate types.
1114 FunctionType *FT = Callee->getFunctionType();
1115 Type *OldRetTy = Caller->getType();
1116 Type *NewRetTy = FT->getReturnType();
1118 if (NewRetTy->isStructTy())
1119 return false; // TODO: Handle multiple return values.
1121 // Check to see if we are changing the return type...
1122 if (OldRetTy != NewRetTy) {
1123 if (Callee->isDeclaration() &&
1124 // Conversion is ok if changing from one pointer type to another or from
1125 // a pointer to an integer of the same size.
1126 !((OldRetTy->isPointerTy() || !TD ||
1127 OldRetTy == TD->getIntPtrType(Caller->getContext())) &&
1128 (NewRetTy->isPointerTy() || !TD ||
1129 NewRetTy == TD->getIntPtrType(Caller->getContext()))))
1130 return false; // Cannot transform this return value.
1132 if (!Caller->use_empty() &&
1133 // void -> non-void is handled specially
1134 !NewRetTy->isVoidTy() && !CastInst::isCastable(NewRetTy, OldRetTy))
1135 return false; // Cannot transform this return value.
1137 if (!CallerPAL.isEmpty() && !Caller->use_empty()) {
1138 Attributes RAttrs = CallerPAL.getRetAttributes();
1139 if (RAttrs & Attribute::typeIncompatible(NewRetTy))
1140 return false; // Attribute not compatible with transformed value.
1143 // If the callsite is an invoke instruction, and the return value is used by
1144 // a PHI node in a successor, we cannot change the return type of the call
1145 // because there is no place to put the cast instruction (without breaking
1146 // the critical edge). Bail out in this case.
1147 if (!Caller->use_empty())
1148 if (InvokeInst *II = dyn_cast<InvokeInst>(Caller))
1149 for (Value::use_iterator UI = II->use_begin(), E = II->use_end();
1151 if (PHINode *PN = dyn_cast<PHINode>(*UI))
1152 if (PN->getParent() == II->getNormalDest() ||
1153 PN->getParent() == II->getUnwindDest())
1157 unsigned NumActualArgs = unsigned(CS.arg_end()-CS.arg_begin());
1158 unsigned NumCommonArgs = std::min(FT->getNumParams(), NumActualArgs);
1160 CallSite::arg_iterator AI = CS.arg_begin();
1161 for (unsigned i = 0, e = NumCommonArgs; i != e; ++i, ++AI) {
1162 Type *ParamTy = FT->getParamType(i);
1163 Type *ActTy = (*AI)->getType();
1165 if (!CastInst::isCastable(ActTy, ParamTy))
1166 return false; // Cannot transform this parameter value.
1168 Attributes Attrs = CallerPAL.getParamAttributes(i + 1);
1169 if (Attrs & Attribute::typeIncompatible(ParamTy))
1170 return false; // Attribute not compatible with transformed value.
1172 // If the parameter is passed as a byval argument, then we have to have a
1173 // sized type and the sized type has to have the same size as the old type.
1174 if (ParamTy != ActTy && (Attrs & Attribute::ByVal)) {
1175 PointerType *ParamPTy = dyn_cast<PointerType>(ParamTy);
1176 if (ParamPTy == 0 || !ParamPTy->getElementType()->isSized() || TD == 0)
1179 Type *CurElTy = cast<PointerType>(ActTy)->getElementType();
1180 if (TD->getTypeAllocSize(CurElTy) !=
1181 TD->getTypeAllocSize(ParamPTy->getElementType()))
1185 // Converting from one pointer type to another or between a pointer and an
1186 // integer of the same size is safe even if we do not have a body.
1187 bool isConvertible = ActTy == ParamTy ||
1188 (TD && ((ParamTy->isPointerTy() ||
1189 ParamTy == TD->getIntPtrType(Caller->getContext())) &&
1190 (ActTy->isPointerTy() ||
1191 ActTy == TD->getIntPtrType(Caller->getContext()))));
1192 if (Callee->isDeclaration() && !isConvertible) return false;
1195 if (Callee->isDeclaration()) {
1196 // Do not delete arguments unless we have a function body.
1197 if (FT->getNumParams() < NumActualArgs && !FT->isVarArg())
1200 // If the callee is just a declaration, don't change the varargsness of the
1201 // call. We don't want to introduce a varargs call where one doesn't
1203 PointerType *APTy = cast<PointerType>(CS.getCalledValue()->getType());
1204 if (FT->isVarArg()!=cast<FunctionType>(APTy->getElementType())->isVarArg())
1207 // If both the callee and the cast type are varargs, we still have to make
1208 // sure the number of fixed parameters are the same or we have the same
1209 // ABI issues as if we introduce a varargs call.
1210 if (FT->isVarArg() &&
1211 cast<FunctionType>(APTy->getElementType())->isVarArg() &&
1212 FT->getNumParams() !=
1213 cast<FunctionType>(APTy->getElementType())->getNumParams())
1217 if (FT->getNumParams() < NumActualArgs && FT->isVarArg() &&
1218 !CallerPAL.isEmpty())
1219 // In this case we have more arguments than the new function type, but we
1220 // won't be dropping them. Check that these extra arguments have attributes
1221 // that are compatible with being a vararg call argument.
1222 for (unsigned i = CallerPAL.getNumSlots(); i; --i) {
1223 if (CallerPAL.getSlot(i - 1).Index <= FT->getNumParams())
1225 Attributes PAttrs = CallerPAL.getSlot(i - 1).Attrs;
1226 if (PAttrs & Attribute::VarArgsIncompatible)
1231 // Okay, we decided that this is a safe thing to do: go ahead and start
1232 // inserting cast instructions as necessary.
1233 std::vector<Value*> Args;
1234 Args.reserve(NumActualArgs);
1235 SmallVector<AttributeWithIndex, 8> attrVec;
1236 attrVec.reserve(NumCommonArgs);
1238 // Get any return attributes.
1239 Attributes RAttrs = CallerPAL.getRetAttributes();
1241 // If the return value is not being used, the type may not be compatible
1242 // with the existing attributes. Wipe out any problematic attributes.
1243 RAttrs &= ~Attribute::typeIncompatible(NewRetTy);
1245 // Add the new return attributes.
1247 attrVec.push_back(AttributeWithIndex::get(0, RAttrs));
1249 AI = CS.arg_begin();
1250 for (unsigned i = 0; i != NumCommonArgs; ++i, ++AI) {
1251 Type *ParamTy = FT->getParamType(i);
1252 if ((*AI)->getType() == ParamTy) {
1253 Args.push_back(*AI);
1255 Instruction::CastOps opcode = CastInst::getCastOpcode(*AI,
1256 false, ParamTy, false);
1257 Args.push_back(Builder->CreateCast(opcode, *AI, ParamTy));
1260 // Add any parameter attributes.
1261 if (Attributes PAttrs = CallerPAL.getParamAttributes(i + 1))
1262 attrVec.push_back(AttributeWithIndex::get(i + 1, PAttrs));
1265 // If the function takes more arguments than the call was taking, add them
1267 for (unsigned i = NumCommonArgs; i != FT->getNumParams(); ++i)
1268 Args.push_back(Constant::getNullValue(FT->getParamType(i)));
1270 // If we are removing arguments to the function, emit an obnoxious warning.
1271 if (FT->getNumParams() < NumActualArgs) {
1272 if (!FT->isVarArg()) {
1273 errs() << "WARNING: While resolving call to function '"
1274 << Callee->getName() << "' arguments were dropped!\n";
1276 // Add all of the arguments in their promoted form to the arg list.
1277 for (unsigned i = FT->getNumParams(); i != NumActualArgs; ++i, ++AI) {
1278 Type *PTy = getPromotedType((*AI)->getType());
1279 if (PTy != (*AI)->getType()) {
1280 // Must promote to pass through va_arg area!
1281 Instruction::CastOps opcode =
1282 CastInst::getCastOpcode(*AI, false, PTy, false);
1283 Args.push_back(Builder->CreateCast(opcode, *AI, PTy));
1285 Args.push_back(*AI);
1288 // Add any parameter attributes.
1289 if (Attributes PAttrs = CallerPAL.getParamAttributes(i + 1))
1290 attrVec.push_back(AttributeWithIndex::get(i + 1, PAttrs));
1295 if (Attributes FnAttrs = CallerPAL.getFnAttributes())
1296 attrVec.push_back(AttributeWithIndex::get(~0, FnAttrs));
1298 if (NewRetTy->isVoidTy())
1299 Caller->setName(""); // Void type should not have a name.
1301 const AttrListPtr &NewCallerPAL = AttrListPtr::get(attrVec.begin(),
1305 if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) {
1306 NC = Builder->CreateInvoke(Callee, II->getNormalDest(),
1307 II->getUnwindDest(), Args);
1309 cast<InvokeInst>(NC)->setCallingConv(II->getCallingConv());
1310 cast<InvokeInst>(NC)->setAttributes(NewCallerPAL);
1312 CallInst *CI = cast<CallInst>(Caller);
1313 NC = Builder->CreateCall(Callee, Args);
1315 if (CI->isTailCall())
1316 cast<CallInst>(NC)->setTailCall();
1317 cast<CallInst>(NC)->setCallingConv(CI->getCallingConv());
1318 cast<CallInst>(NC)->setAttributes(NewCallerPAL);
1321 // Insert a cast of the return type as necessary.
1323 if (OldRetTy != NV->getType() && !Caller->use_empty()) {
1324 if (!NV->getType()->isVoidTy()) {
1325 Instruction::CastOps opcode =
1326 CastInst::getCastOpcode(NC, false, OldRetTy, false);
1327 NV = NC = CastInst::Create(opcode, NC, OldRetTy);
1328 NC->setDebugLoc(Caller->getDebugLoc());
1330 // If this is an invoke instruction, we should insert it after the first
1331 // non-phi, instruction in the normal successor block.
1332 if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) {
1333 BasicBlock::iterator I = II->getNormalDest()->getFirstInsertionPt();
1334 InsertNewInstBefore(NC, *I);
1336 // Otherwise, it's a call, just insert cast right after the call.
1337 InsertNewInstBefore(NC, *Caller);
1339 Worklist.AddUsersToWorkList(*Caller);
1341 NV = UndefValue::get(Caller->getType());
1345 if (!Caller->use_empty())
1346 ReplaceInstUsesWith(*Caller, NV);
1348 EraseInstFromFunction(*Caller);
1352 // transformCallThroughTrampoline - Turn a call to a function created by
1353 // init_trampoline / adjust_trampoline intrinsic pair into a direct call to the
1354 // underlying function.
1357 InstCombiner::transformCallThroughTrampoline(CallSite CS,
1358 IntrinsicInst *Tramp) {
1359 Value *Callee = CS.getCalledValue();
1360 PointerType *PTy = cast<PointerType>(Callee->getType());
1361 FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1362 const AttrListPtr &Attrs = CS.getAttributes();
1364 // If the call already has the 'nest' attribute somewhere then give up -
1365 // otherwise 'nest' would occur twice after splicing in the chain.
1366 if (Attrs.hasAttrSomewhere(Attribute::Nest))
1370 "transformCallThroughTrampoline called with incorrect CallSite.");
1372 Function *NestF =cast<Function>(Tramp->getArgOperand(1)->stripPointerCasts());
1373 PointerType *NestFPTy = cast<PointerType>(NestF->getType());
1374 FunctionType *NestFTy = cast<FunctionType>(NestFPTy->getElementType());
1376 const AttrListPtr &NestAttrs = NestF->getAttributes();
1377 if (!NestAttrs.isEmpty()) {
1378 unsigned NestIdx = 1;
1380 Attributes NestAttr = Attribute::None;
1382 // Look for a parameter marked with the 'nest' attribute.
1383 for (FunctionType::param_iterator I = NestFTy->param_begin(),
1384 E = NestFTy->param_end(); I != E; ++NestIdx, ++I)
1385 if (NestAttrs.paramHasAttr(NestIdx, Attribute::Nest)) {
1386 // Record the parameter type and any other attributes.
1388 NestAttr = NestAttrs.getParamAttributes(NestIdx);
1393 Instruction *Caller = CS.getInstruction();
1394 std::vector<Value*> NewArgs;
1395 NewArgs.reserve(unsigned(CS.arg_end()-CS.arg_begin())+1);
1397 SmallVector<AttributeWithIndex, 8> NewAttrs;
1398 NewAttrs.reserve(Attrs.getNumSlots() + 1);
1400 // Insert the nest argument into the call argument list, which may
1401 // mean appending it. Likewise for attributes.
1403 // Add any result attributes.
1404 if (Attributes Attr = Attrs.getRetAttributes())
1405 NewAttrs.push_back(AttributeWithIndex::get(0, Attr));
1409 CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end();
1411 if (Idx == NestIdx) {
1412 // Add the chain argument and attributes.
1413 Value *NestVal = Tramp->getArgOperand(2);
1414 if (NestVal->getType() != NestTy)
1415 NestVal = Builder->CreateBitCast(NestVal, NestTy, "nest");
1416 NewArgs.push_back(NestVal);
1417 NewAttrs.push_back(AttributeWithIndex::get(NestIdx, NestAttr));
1423 // Add the original argument and attributes.
1424 NewArgs.push_back(*I);
1425 if (Attributes Attr = Attrs.getParamAttributes(Idx))
1427 (AttributeWithIndex::get(Idx + (Idx >= NestIdx), Attr));
1433 // Add any function attributes.
1434 if (Attributes Attr = Attrs.getFnAttributes())
1435 NewAttrs.push_back(AttributeWithIndex::get(~0, Attr));
1437 // The trampoline may have been bitcast to a bogus type (FTy).
1438 // Handle this by synthesizing a new function type, equal to FTy
1439 // with the chain parameter inserted.
1441 std::vector<Type*> NewTypes;
1442 NewTypes.reserve(FTy->getNumParams()+1);
1444 // Insert the chain's type into the list of parameter types, which may
1445 // mean appending it.
1448 FunctionType::param_iterator I = FTy->param_begin(),
1449 E = FTy->param_end();
1453 // Add the chain's type.
1454 NewTypes.push_back(NestTy);
1459 // Add the original type.
1460 NewTypes.push_back(*I);
1466 // Replace the trampoline call with a direct call. Let the generic
1467 // code sort out any function type mismatches.
1468 FunctionType *NewFTy = FunctionType::get(FTy->getReturnType(), NewTypes,
1470 Constant *NewCallee =
1471 NestF->getType() == PointerType::getUnqual(NewFTy) ?
1472 NestF : ConstantExpr::getBitCast(NestF,
1473 PointerType::getUnqual(NewFTy));
1474 const AttrListPtr &NewPAL = AttrListPtr::get(NewAttrs.begin(),
1477 Instruction *NewCaller;
1478 if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) {
1479 NewCaller = InvokeInst::Create(NewCallee,
1480 II->getNormalDest(), II->getUnwindDest(),
1482 cast<InvokeInst>(NewCaller)->setCallingConv(II->getCallingConv());
1483 cast<InvokeInst>(NewCaller)->setAttributes(NewPAL);
1485 NewCaller = CallInst::Create(NewCallee, NewArgs);
1486 if (cast<CallInst>(Caller)->isTailCall())
1487 cast<CallInst>(NewCaller)->setTailCall();
1488 cast<CallInst>(NewCaller)->
1489 setCallingConv(cast<CallInst>(Caller)->getCallingConv());
1490 cast<CallInst>(NewCaller)->setAttributes(NewPAL);
1497 // Replace the trampoline call with a direct call. Since there is no 'nest'
1498 // parameter, there is no need to adjust the argument list. Let the generic
1499 // code sort out any function type mismatches.
1500 Constant *NewCallee =
1501 NestF->getType() == PTy ? NestF :
1502 ConstantExpr::getBitCast(NestF, PTy);
1503 CS.setCalledFunction(NewCallee);
1504 return CS.getInstruction();