mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-29 13:29:28 +00:00
with a fix rotate CallInst operands, i.e. move callee to the back of the operand array the motivation for this patch are laid out in my mail to llvm-commits: more efficient access to operands and callee, faster callgraph-construction, smaller compiler binary git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101397 91177308-0d34-0410-b5e6-96231b3b80d8
1277 lines
50 KiB
C++
1277 lines
50 KiB
C++
//===- InstCombineCalls.cpp -----------------------------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements the visitCall and visitInvoke functions.
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//
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//===----------------------------------------------------------------------===//
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#include "InstCombine.h"
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#include "llvm/IntrinsicInst.h"
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#include "llvm/Support/CallSite.h"
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#include "llvm/Target/TargetData.h"
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#include "llvm/Analysis/MemoryBuiltins.h"
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#include "llvm/Transforms/Utils/BuildLibCalls.h"
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using namespace llvm;
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/// getPromotedType - Return the specified type promoted as it would be to pass
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/// though a va_arg area.
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static const Type *getPromotedType(const Type *Ty) {
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if (const IntegerType* ITy = dyn_cast<IntegerType>(Ty)) {
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if (ITy->getBitWidth() < 32)
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return Type::getInt32Ty(Ty->getContext());
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}
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return Ty;
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}
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/// EnforceKnownAlignment - If the specified pointer points to an object that
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/// we control, modify the object's alignment to PrefAlign. This isn't
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/// often possible though. If alignment is important, a more reliable approach
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/// is to simply align all global variables and allocation instructions to
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/// their preferred alignment from the beginning.
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///
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static unsigned EnforceKnownAlignment(Value *V,
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unsigned Align, unsigned PrefAlign) {
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User *U = dyn_cast<User>(V);
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if (!U) return Align;
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switch (Operator::getOpcode(U)) {
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default: break;
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case Instruction::BitCast:
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return EnforceKnownAlignment(U->getOperand(0), Align, PrefAlign);
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case Instruction::GetElementPtr: {
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// If all indexes are zero, it is just the alignment of the base pointer.
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bool AllZeroOperands = true;
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for (User::op_iterator i = U->op_begin() + 1, e = U->op_end(); i != e; ++i)
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if (!isa<Constant>(*i) ||
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!cast<Constant>(*i)->isNullValue()) {
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AllZeroOperands = false;
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break;
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}
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if (AllZeroOperands) {
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// Treat this like a bitcast.
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return EnforceKnownAlignment(U->getOperand(0), Align, PrefAlign);
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}
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break;
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}
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}
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if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
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// If there is a large requested alignment and we can, bump up the alignment
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// of the global.
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if (!GV->isDeclaration()) {
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if (GV->getAlignment() >= PrefAlign)
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Align = GV->getAlignment();
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else {
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GV->setAlignment(PrefAlign);
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Align = PrefAlign;
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}
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}
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} else if (AllocaInst *AI = dyn_cast<AllocaInst>(V)) {
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// If there is a requested alignment and if this is an alloca, round up.
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if (AI->getAlignment() >= PrefAlign)
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Align = AI->getAlignment();
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else {
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AI->setAlignment(PrefAlign);
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Align = PrefAlign;
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}
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}
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return Align;
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}
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/// GetOrEnforceKnownAlignment - If the specified pointer has an alignment that
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/// we can determine, return it, otherwise return 0. If PrefAlign is specified,
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/// and it is more than the alignment of the ultimate object, see if we can
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/// increase the alignment of the ultimate object, making this check succeed.
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unsigned InstCombiner::GetOrEnforceKnownAlignment(Value *V,
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unsigned PrefAlign) {
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unsigned BitWidth = TD ? TD->getTypeSizeInBits(V->getType()) :
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sizeof(PrefAlign) * CHAR_BIT;
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APInt Mask = APInt::getAllOnesValue(BitWidth);
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APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
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ComputeMaskedBits(V, Mask, KnownZero, KnownOne);
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unsigned TrailZ = KnownZero.countTrailingOnes();
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unsigned Align = 1u << std::min(BitWidth - 1, TrailZ);
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if (PrefAlign > Align)
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Align = EnforceKnownAlignment(V, Align, PrefAlign);
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// We don't need to make any adjustment.
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return Align;
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}
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Instruction *InstCombiner::SimplifyMemTransfer(MemIntrinsic *MI) {
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unsigned DstAlign = GetOrEnforceKnownAlignment(MI->getOperand(0));
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unsigned SrcAlign = GetOrEnforceKnownAlignment(MI->getOperand(1));
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unsigned MinAlign = std::min(DstAlign, SrcAlign);
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unsigned CopyAlign = MI->getAlignment();
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if (CopyAlign < MinAlign) {
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MI->setAlignment(ConstantInt::get(MI->getAlignmentType(),
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MinAlign, false));
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return MI;
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}
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// If MemCpyInst length is 1/2/4/8 bytes then replace memcpy with
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// load/store.
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ConstantInt *MemOpLength = dyn_cast<ConstantInt>(MI->getOperand(2));
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if (MemOpLength == 0) return 0;
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// Source and destination pointer types are always "i8*" for intrinsic. See
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// if the size is something we can handle with a single primitive load/store.
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// A single load+store correctly handles overlapping memory in the memmove
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// case.
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unsigned Size = MemOpLength->getZExtValue();
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if (Size == 0) return MI; // Delete this mem transfer.
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if (Size > 8 || (Size&(Size-1)))
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return 0; // If not 1/2/4/8 bytes, exit.
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// Use an integer load+store unless we can find something better.
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unsigned SrcAddrSp =
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cast<PointerType>(MI->getOperand(1)->getType())->getAddressSpace();
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unsigned DstAddrSp =
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cast<PointerType>(MI->getOperand(0)->getType())->getAddressSpace();
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const IntegerType* IntType = IntegerType::get(MI->getContext(), Size<<3);
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Type *NewSrcPtrTy = PointerType::get(IntType, SrcAddrSp);
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Type *NewDstPtrTy = PointerType::get(IntType, DstAddrSp);
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// Memcpy forces the use of i8* for the source and destination. That means
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// that if you're using memcpy to move one double around, you'll get a cast
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// from double* to i8*. We'd much rather use a double load+store rather than
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// an i64 load+store, here because this improves the odds that the source or
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// dest address will be promotable. See if we can find a better type than the
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// integer datatype.
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Value *StrippedDest = MI->getOperand(0)->stripPointerCasts();
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if (StrippedDest != MI->getOperand(0)) {
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const Type *SrcETy = cast<PointerType>(StrippedDest->getType())
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->getElementType();
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if (TD && SrcETy->isSized() && TD->getTypeStoreSize(SrcETy) == Size) {
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// The SrcETy might be something like {{{double}}} or [1 x double]. Rip
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// down through these levels if so.
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while (!SrcETy->isSingleValueType()) {
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if (const StructType *STy = dyn_cast<StructType>(SrcETy)) {
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if (STy->getNumElements() == 1)
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SrcETy = STy->getElementType(0);
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else
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break;
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} else if (const ArrayType *ATy = dyn_cast<ArrayType>(SrcETy)) {
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if (ATy->getNumElements() == 1)
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SrcETy = ATy->getElementType();
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else
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break;
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} else
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break;
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}
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if (SrcETy->isSingleValueType()) {
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NewSrcPtrTy = PointerType::get(SrcETy, SrcAddrSp);
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NewDstPtrTy = PointerType::get(SrcETy, DstAddrSp);
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}
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}
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}
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// If the memcpy/memmove provides better alignment info than we can
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// infer, use it.
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SrcAlign = std::max(SrcAlign, CopyAlign);
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DstAlign = std::max(DstAlign, CopyAlign);
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Value *Src = Builder->CreateBitCast(MI->getOperand(1), NewSrcPtrTy);
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Value *Dest = Builder->CreateBitCast(MI->getOperand(0), NewDstPtrTy);
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Instruction *L = new LoadInst(Src, "tmp", MI->isVolatile(), SrcAlign);
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InsertNewInstBefore(L, *MI);
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InsertNewInstBefore(new StoreInst(L, Dest, MI->isVolatile(), DstAlign),
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*MI);
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// Set the size of the copy to 0, it will be deleted on the next iteration.
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MI->setOperand(2, Constant::getNullValue(MemOpLength->getType()));
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return MI;
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}
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Instruction *InstCombiner::SimplifyMemSet(MemSetInst *MI) {
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unsigned Alignment = GetOrEnforceKnownAlignment(MI->getDest());
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if (MI->getAlignment() < Alignment) {
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MI->setAlignment(ConstantInt::get(MI->getAlignmentType(),
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Alignment, false));
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return MI;
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}
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// Extract the length and alignment and fill if they are constant.
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ConstantInt *LenC = dyn_cast<ConstantInt>(MI->getLength());
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ConstantInt *FillC = dyn_cast<ConstantInt>(MI->getValue());
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if (!LenC || !FillC || !FillC->getType()->isIntegerTy(8))
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return 0;
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uint64_t Len = LenC->getZExtValue();
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Alignment = MI->getAlignment();
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// If the length is zero, this is a no-op
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if (Len == 0) return MI; // memset(d,c,0,a) -> noop
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// memset(s,c,n) -> store s, c (for n=1,2,4,8)
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if (Len <= 8 && isPowerOf2_32((uint32_t)Len)) {
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const Type *ITy = IntegerType::get(MI->getContext(), Len*8); // n=1 -> i8.
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Value *Dest = MI->getDest();
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Dest = Builder->CreateBitCast(Dest, PointerType::getUnqual(ITy));
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// Alignment 0 is identity for alignment 1 for memset, but not store.
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if (Alignment == 0) Alignment = 1;
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// Extract the fill value and store.
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uint64_t Fill = FillC->getZExtValue()*0x0101010101010101ULL;
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InsertNewInstBefore(new StoreInst(ConstantInt::get(ITy, Fill),
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Dest, false, Alignment), *MI);
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// Set the size of the copy to 0, it will be deleted on the next iteration.
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MI->setLength(Constant::getNullValue(LenC->getType()));
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return MI;
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}
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return 0;
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}
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/// visitCallInst - CallInst simplification. This mostly only handles folding
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/// of intrinsic instructions. For normal calls, it allows visitCallSite to do
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/// the heavy lifting.
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///
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Instruction *InstCombiner::visitCallInst(CallInst &CI) {
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if (isFreeCall(&CI))
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return visitFree(CI);
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// If the caller function is nounwind, mark the call as nounwind, even if the
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// callee isn't.
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if (CI.getParent()->getParent()->doesNotThrow() &&
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!CI.doesNotThrow()) {
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CI.setDoesNotThrow();
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return &CI;
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}
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IntrinsicInst *II = dyn_cast<IntrinsicInst>(&CI);
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if (!II) return visitCallSite(&CI);
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// Intrinsics cannot occur in an invoke, so handle them here instead of in
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// visitCallSite.
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if (MemIntrinsic *MI = dyn_cast<MemIntrinsic>(II)) {
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bool Changed = false;
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// memmove/cpy/set of zero bytes is a noop.
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if (Constant *NumBytes = dyn_cast<Constant>(MI->getLength())) {
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if (NumBytes->isNullValue()) return EraseInstFromFunction(CI);
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if (ConstantInt *CI = dyn_cast<ConstantInt>(NumBytes))
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if (CI->getZExtValue() == 1) {
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// Replace the instruction with just byte operations. We would
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// transform other cases to loads/stores, but we don't know if
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// alignment is sufficient.
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}
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}
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// If we have a memmove and the source operation is a constant global,
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// then the source and dest pointers can't alias, so we can change this
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// into a call to memcpy.
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if (MemMoveInst *MMI = dyn_cast<MemMoveInst>(MI)) {
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if (GlobalVariable *GVSrc = dyn_cast<GlobalVariable>(MMI->getSource()))
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if (GVSrc->isConstant()) {
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Module *M = MMI->getParent()->getParent()->getParent();
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Intrinsic::ID MemCpyID = Intrinsic::memcpy;
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const Type *Tys[3] = { CI.getOperand(0)->getType(),
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CI.getOperand(1)->getType(),
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CI.getOperand(2)->getType() };
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MMI->setCalledFunction(
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Intrinsic::getDeclaration(M, MemCpyID, Tys, 3));
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Changed = true;
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}
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}
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if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(MI)) {
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// memmove(x,x,size) -> noop.
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if (MTI->getSource() == MTI->getDest())
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return EraseInstFromFunction(CI);
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// If we can determine a pointer alignment that is bigger than currently
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// set, update the alignment.
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if (Instruction *I = SimplifyMemTransfer(MTI))
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return I;
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} else if (MemSetInst *MSI = dyn_cast<MemSetInst>(MI)) {
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if (Instruction *I = SimplifyMemSet(MSI))
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return I;
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}
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if (Changed) return II;
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}
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switch (II->getIntrinsicID()) {
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default: break;
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case Intrinsic::objectsize: {
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// We need target data for just about everything so depend on it.
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if (!TD) break;
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const Type *ReturnTy = CI.getType();
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bool Min = (cast<ConstantInt>(II->getOperand(1))->getZExtValue() == 1);
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// Get to the real allocated thing and offset as fast as possible.
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Value *Op1 = II->getOperand(0)->stripPointerCasts();
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// If we've stripped down to a single global variable that we
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// can know the size of then just return that.
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if (GlobalVariable *GV = dyn_cast<GlobalVariable>(Op1)) {
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if (GV->hasDefinitiveInitializer()) {
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Constant *C = GV->getInitializer();
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uint64_t GlobalSize = TD->getTypeAllocSize(C->getType());
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return ReplaceInstUsesWith(CI, ConstantInt::get(ReturnTy, GlobalSize));
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} else {
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// Can't determine size of the GV.
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Constant *RetVal = ConstantInt::get(ReturnTy, Min ? 0 : -1ULL);
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return ReplaceInstUsesWith(CI, RetVal);
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}
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} else if (AllocaInst *AI = dyn_cast<AllocaInst>(Op1)) {
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// Get alloca size.
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if (AI->getAllocatedType()->isSized()) {
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uint64_t AllocaSize = TD->getTypeAllocSize(AI->getAllocatedType());
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if (AI->isArrayAllocation()) {
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const ConstantInt *C = dyn_cast<ConstantInt>(AI->getArraySize());
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if (!C) break;
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AllocaSize *= C->getZExtValue();
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}
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return ReplaceInstUsesWith(CI, ConstantInt::get(ReturnTy, AllocaSize));
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}
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} else if (CallInst *MI = extractMallocCall(Op1)) {
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const Type* MallocType = getMallocAllocatedType(MI);
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// Get alloca size.
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if (MallocType && MallocType->isSized()) {
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if (Value *NElems = getMallocArraySize(MI, TD, true)) {
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if (ConstantInt *NElements = dyn_cast<ConstantInt>(NElems))
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return ReplaceInstUsesWith(CI, ConstantInt::get(ReturnTy,
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(NElements->getZExtValue() * TD->getTypeAllocSize(MallocType))));
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}
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}
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} else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Op1)) {
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// Only handle constant GEPs here.
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if (CE->getOpcode() != Instruction::GetElementPtr) break;
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GEPOperator *GEP = cast<GEPOperator>(CE);
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// Make sure we're not a constant offset from an external
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// global.
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Value *Operand = GEP->getPointerOperand();
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Operand = Operand->stripPointerCasts();
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if (GlobalVariable *GV = dyn_cast<GlobalVariable>(Operand))
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if (!GV->hasDefinitiveInitializer()) break;
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// Get what we're pointing to and its size.
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const PointerType *BaseType =
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cast<PointerType>(Operand->getType());
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uint64_t Size = TD->getTypeAllocSize(BaseType->getElementType());
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// Get the current byte offset into the thing. Use the original
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// operand in case we're looking through a bitcast.
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SmallVector<Value*, 8> Ops(CE->op_begin()+1, CE->op_end());
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const PointerType *OffsetType =
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cast<PointerType>(GEP->getPointerOperand()->getType());
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uint64_t Offset = TD->getIndexedOffset(OffsetType, &Ops[0], Ops.size());
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if (Size < Offset) {
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// Out of bound reference? Negative index normalized to large
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// index? Just return "I don't know".
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Constant *RetVal = ConstantInt::get(ReturnTy, Min ? 0 : -1ULL);
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return ReplaceInstUsesWith(CI, RetVal);
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}
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Constant *RetVal = ConstantInt::get(ReturnTy, Size-Offset);
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return ReplaceInstUsesWith(CI, RetVal);
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}
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// Do not return "I don't know" here. Later optimization passes could
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// make it possible to evaluate objectsize to a constant.
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break;
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}
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case Intrinsic::bswap:
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// bswap(bswap(x)) -> x
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if (IntrinsicInst *Operand = dyn_cast<IntrinsicInst>(II->getOperand(0)))
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if (Operand->getIntrinsicID() == Intrinsic::bswap)
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return ReplaceInstUsesWith(CI, Operand->getOperand(0));
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// bswap(trunc(bswap(x))) -> trunc(lshr(x, c))
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if (TruncInst *TI = dyn_cast<TruncInst>(II->getOperand(0))) {
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if (IntrinsicInst *Operand = dyn_cast<IntrinsicInst>(TI->getOperand(0)))
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if (Operand->getIntrinsicID() == Intrinsic::bswap) {
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unsigned C = Operand->getType()->getPrimitiveSizeInBits() -
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TI->getType()->getPrimitiveSizeInBits();
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Value *CV = ConstantInt::get(Operand->getType(), C);
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Value *V = Builder->CreateLShr(Operand->getOperand(0), CV);
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return new TruncInst(V, TI->getType());
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}
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}
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break;
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case Intrinsic::powi:
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if (ConstantInt *Power = dyn_cast<ConstantInt>(II->getOperand(1))) {
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// powi(x, 0) -> 1.0
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if (Power->isZero())
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return ReplaceInstUsesWith(CI, ConstantFP::get(CI.getType(), 1.0));
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// powi(x, 1) -> x
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if (Power->isOne())
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return ReplaceInstUsesWith(CI, II->getOperand(0));
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// powi(x, -1) -> 1/x
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if (Power->isAllOnesValue())
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return BinaryOperator::CreateFDiv(ConstantFP::get(CI.getType(), 1.0),
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II->getOperand(0));
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}
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break;
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case Intrinsic::cttz: {
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// If all bits below the first known one are known zero,
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// this value is constant.
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const IntegerType *IT = cast<IntegerType>(II->getOperand(0)->getType());
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uint32_t BitWidth = IT->getBitWidth();
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APInt KnownZero(BitWidth, 0);
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APInt KnownOne(BitWidth, 0);
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ComputeMaskedBits(II->getOperand(0), APInt::getAllOnesValue(BitWidth),
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KnownZero, KnownOne);
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unsigned TrailingZeros = KnownOne.countTrailingZeros();
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APInt Mask(APInt::getLowBitsSet(BitWidth, TrailingZeros));
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if ((Mask & KnownZero) == Mask)
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return ReplaceInstUsesWith(CI, ConstantInt::get(IT,
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APInt(BitWidth, TrailingZeros)));
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|
}
|
|
break;
|
|
case Intrinsic::ctlz: {
|
|
// If all bits above the first known one are known zero,
|
|
// this value is constant.
|
|
const IntegerType *IT = cast<IntegerType>(II->getOperand(0)->getType());
|
|
uint32_t BitWidth = IT->getBitWidth();
|
|
APInt KnownZero(BitWidth, 0);
|
|
APInt KnownOne(BitWidth, 0);
|
|
ComputeMaskedBits(II->getOperand(0), APInt::getAllOnesValue(BitWidth),
|
|
KnownZero, KnownOne);
|
|
unsigned LeadingZeros = KnownOne.countLeadingZeros();
|
|
APInt Mask(APInt::getHighBitsSet(BitWidth, LeadingZeros));
|
|
if ((Mask & KnownZero) == Mask)
|
|
return ReplaceInstUsesWith(CI, ConstantInt::get(IT,
|
|
APInt(BitWidth, LeadingZeros)));
|
|
|
|
}
|
|
break;
|
|
case Intrinsic::uadd_with_overflow: {
|
|
Value *LHS = II->getOperand(0), *RHS = II->getOperand(1);
|
|
const IntegerType *IT = cast<IntegerType>(II->getOperand(0)->getType());
|
|
uint32_t BitWidth = IT->getBitWidth();
|
|
APInt Mask = APInt::getSignBit(BitWidth);
|
|
APInt LHSKnownZero(BitWidth, 0);
|
|
APInt LHSKnownOne(BitWidth, 0);
|
|
ComputeMaskedBits(LHS, Mask, LHSKnownZero, LHSKnownOne);
|
|
bool LHSKnownNegative = LHSKnownOne[BitWidth - 1];
|
|
bool LHSKnownPositive = LHSKnownZero[BitWidth - 1];
|
|
|
|
if (LHSKnownNegative || LHSKnownPositive) {
|
|
APInt RHSKnownZero(BitWidth, 0);
|
|
APInt RHSKnownOne(BitWidth, 0);
|
|
ComputeMaskedBits(RHS, Mask, RHSKnownZero, RHSKnownOne);
|
|
bool RHSKnownNegative = RHSKnownOne[BitWidth - 1];
|
|
bool RHSKnownPositive = RHSKnownZero[BitWidth - 1];
|
|
if (LHSKnownNegative && RHSKnownNegative) {
|
|
// The sign bit is set in both cases: this MUST overflow.
|
|
// Create a simple add instruction, and insert it into the struct.
|
|
Instruction *Add = BinaryOperator::CreateAdd(LHS, RHS, "", &CI);
|
|
Worklist.Add(Add);
|
|
Constant *V[] = {
|
|
UndefValue::get(LHS->getType()),ConstantInt::getTrue(II->getContext())
|
|
};
|
|
Constant *Struct = ConstantStruct::get(II->getContext(), V, 2, false);
|
|
return InsertValueInst::Create(Struct, Add, 0);
|
|
}
|
|
|
|
if (LHSKnownPositive && RHSKnownPositive) {
|
|
// The sign bit is clear in both cases: this CANNOT overflow.
|
|
// Create a simple add instruction, and insert it into the struct.
|
|
Instruction *Add = BinaryOperator::CreateNUWAdd(LHS, RHS, "", &CI);
|
|
Worklist.Add(Add);
|
|
Constant *V[] = {
|
|
UndefValue::get(LHS->getType()),
|
|
ConstantInt::getFalse(II->getContext())
|
|
};
|
|
Constant *Struct = ConstantStruct::get(II->getContext(), V, 2, false);
|
|
return InsertValueInst::Create(Struct, Add, 0);
|
|
}
|
|
}
|
|
}
|
|
// FALL THROUGH uadd into sadd
|
|
case Intrinsic::sadd_with_overflow:
|
|
// Canonicalize constants into the RHS.
|
|
if (isa<Constant>(II->getOperand(0)) &&
|
|
!isa<Constant>(II->getOperand(1))) {
|
|
Value *LHS = II->getOperand(0);
|
|
II->setOperand(0, II->getOperand(1));
|
|
II->setOperand(1, LHS);
|
|
return II;
|
|
}
|
|
|
|
// X + undef -> undef
|
|
if (isa<UndefValue>(II->getOperand(1)))
|
|
return ReplaceInstUsesWith(CI, UndefValue::get(II->getType()));
|
|
|
|
if (ConstantInt *RHS = dyn_cast<ConstantInt>(II->getOperand(1))) {
|
|
// X + 0 -> {X, false}
|
|
if (RHS->isZero()) {
|
|
Constant *V[] = {
|
|
UndefValue::get(II->getOperand(0)->getType()),
|
|
ConstantInt::getFalse(II->getContext())
|
|
};
|
|
Constant *Struct = ConstantStruct::get(II->getContext(), V, 2, false);
|
|
return InsertValueInst::Create(Struct, II->getOperand(0), 0);
|
|
}
|
|
}
|
|
break;
|
|
case Intrinsic::usub_with_overflow:
|
|
case Intrinsic::ssub_with_overflow:
|
|
// undef - X -> undef
|
|
// X - undef -> undef
|
|
if (isa<UndefValue>(II->getOperand(0)) ||
|
|
isa<UndefValue>(II->getOperand(1)))
|
|
return ReplaceInstUsesWith(CI, UndefValue::get(II->getType()));
|
|
|
|
if (ConstantInt *RHS = dyn_cast<ConstantInt>(II->getOperand(1))) {
|
|
// X - 0 -> {X, false}
|
|
if (RHS->isZero()) {
|
|
Constant *V[] = {
|
|
UndefValue::get(II->getOperand(0)->getType()),
|
|
ConstantInt::getFalse(II->getContext())
|
|
};
|
|
Constant *Struct = ConstantStruct::get(II->getContext(), V, 2, false);
|
|
return InsertValueInst::Create(Struct, II->getOperand(0), 0);
|
|
}
|
|
}
|
|
break;
|
|
case Intrinsic::umul_with_overflow:
|
|
case Intrinsic::smul_with_overflow:
|
|
// Canonicalize constants into the RHS.
|
|
if (isa<Constant>(II->getOperand(0)) &&
|
|
!isa<Constant>(II->getOperand(1))) {
|
|
Value *LHS = II->getOperand(0);
|
|
II->setOperand(0, II->getOperand(1));
|
|
II->setOperand(1, LHS);
|
|
return II;
|
|
}
|
|
|
|
// X * undef -> undef
|
|
if (isa<UndefValue>(II->getOperand(1)))
|
|
return ReplaceInstUsesWith(CI, UndefValue::get(II->getType()));
|
|
|
|
if (ConstantInt *RHSI = dyn_cast<ConstantInt>(II->getOperand(1))) {
|
|
// X*0 -> {0, false}
|
|
if (RHSI->isZero())
|
|
return ReplaceInstUsesWith(CI, Constant::getNullValue(II->getType()));
|
|
|
|
// X * 1 -> {X, false}
|
|
if (RHSI->equalsInt(1)) {
|
|
Constant *V[] = {
|
|
UndefValue::get(II->getOperand(0)->getType()),
|
|
ConstantInt::getFalse(II->getContext())
|
|
};
|
|
Constant *Struct = ConstantStruct::get(II->getContext(), V, 2, false);
|
|
return InsertValueInst::Create(Struct, II->getOperand(0), 0);
|
|
}
|
|
}
|
|
break;
|
|
case Intrinsic::ppc_altivec_lvx:
|
|
case Intrinsic::ppc_altivec_lvxl:
|
|
case Intrinsic::x86_sse_loadu_ps:
|
|
case Intrinsic::x86_sse2_loadu_pd:
|
|
case Intrinsic::x86_sse2_loadu_dq:
|
|
// Turn PPC lvx -> load if the pointer is known aligned.
|
|
// Turn X86 loadups -> load if the pointer is known aligned.
|
|
if (GetOrEnforceKnownAlignment(II->getOperand(0), 16) >= 16) {
|
|
Value *Ptr = Builder->CreateBitCast(II->getOperand(0),
|
|
PointerType::getUnqual(II->getType()));
|
|
return new LoadInst(Ptr);
|
|
}
|
|
break;
|
|
case Intrinsic::ppc_altivec_stvx:
|
|
case Intrinsic::ppc_altivec_stvxl:
|
|
// Turn stvx -> store if the pointer is known aligned.
|
|
if (GetOrEnforceKnownAlignment(II->getOperand(1), 16) >= 16) {
|
|
const Type *OpPtrTy =
|
|
PointerType::getUnqual(II->getOperand(0)->getType());
|
|
Value *Ptr = Builder->CreateBitCast(II->getOperand(1), OpPtrTy);
|
|
return new StoreInst(II->getOperand(0), Ptr);
|
|
}
|
|
break;
|
|
case Intrinsic::x86_sse_storeu_ps:
|
|
case Intrinsic::x86_sse2_storeu_pd:
|
|
case Intrinsic::x86_sse2_storeu_dq:
|
|
// Turn X86 storeu -> store if the pointer is known aligned.
|
|
if (GetOrEnforceKnownAlignment(II->getOperand(0), 16) >= 16) {
|
|
const Type *OpPtrTy =
|
|
PointerType::getUnqual(II->getOperand(1)->getType());
|
|
Value *Ptr = Builder->CreateBitCast(II->getOperand(0), OpPtrTy);
|
|
return new StoreInst(II->getOperand(1), Ptr);
|
|
}
|
|
break;
|
|
|
|
case Intrinsic::x86_sse_cvttss2si: {
|
|
// These intrinsics only demands the 0th element of its input vector. If
|
|
// we can simplify the input based on that, do so now.
|
|
unsigned VWidth =
|
|
cast<VectorType>(II->getOperand(0)->getType())->getNumElements();
|
|
APInt DemandedElts(VWidth, 1);
|
|
APInt UndefElts(VWidth, 0);
|
|
if (Value *V = SimplifyDemandedVectorElts(II->getOperand(0), DemandedElts,
|
|
UndefElts)) {
|
|
II->setOperand(0, V);
|
|
return II;
|
|
}
|
|
break;
|
|
}
|
|
|
|
case Intrinsic::ppc_altivec_vperm:
|
|
// Turn vperm(V1,V2,mask) -> shuffle(V1,V2,mask) if mask is a constant.
|
|
if (ConstantVector *Mask = dyn_cast<ConstantVector>(II->getOperand(2))) {
|
|
assert(Mask->getNumOperands() == 16 && "Bad type for intrinsic!");
|
|
|
|
// Check that all of the elements are integer constants or undefs.
|
|
bool AllEltsOk = true;
|
|
for (unsigned i = 0; i != 16; ++i) {
|
|
if (!isa<ConstantInt>(Mask->getOperand(i)) &&
|
|
!isa<UndefValue>(Mask->getOperand(i))) {
|
|
AllEltsOk = false;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (AllEltsOk) {
|
|
// Cast the input vectors to byte vectors.
|
|
Value *Op0 = Builder->CreateBitCast(II->getOperand(0), Mask->getType());
|
|
Value *Op1 = Builder->CreateBitCast(II->getOperand(1), Mask->getType());
|
|
Value *Result = UndefValue::get(Op0->getType());
|
|
|
|
// Only extract each element once.
|
|
Value *ExtractedElts[32];
|
|
memset(ExtractedElts, 0, sizeof(ExtractedElts));
|
|
|
|
for (unsigned i = 0; i != 16; ++i) {
|
|
if (isa<UndefValue>(Mask->getOperand(i)))
|
|
continue;
|
|
unsigned Idx=cast<ConstantInt>(Mask->getOperand(i))->getZExtValue();
|
|
Idx &= 31; // Match the hardware behavior.
|
|
|
|
if (ExtractedElts[Idx] == 0) {
|
|
ExtractedElts[Idx] =
|
|
Builder->CreateExtractElement(Idx < 16 ? Op0 : Op1,
|
|
ConstantInt::get(Type::getInt32Ty(II->getContext()),
|
|
Idx&15, false), "tmp");
|
|
}
|
|
|
|
// Insert this value into the result vector.
|
|
Result = Builder->CreateInsertElement(Result, ExtractedElts[Idx],
|
|
ConstantInt::get(Type::getInt32Ty(II->getContext()),
|
|
i, false), "tmp");
|
|
}
|
|
return CastInst::Create(Instruction::BitCast, Result, CI.getType());
|
|
}
|
|
}
|
|
break;
|
|
|
|
case Intrinsic::stackrestore: {
|
|
// If the save is right next to the restore, remove the restore. This can
|
|
// happen when variable allocas are DCE'd.
|
|
if (IntrinsicInst *SS = dyn_cast<IntrinsicInst>(II->getOperand(0))) {
|
|
if (SS->getIntrinsicID() == Intrinsic::stacksave) {
|
|
BasicBlock::iterator BI = SS;
|
|
if (&*++BI == II)
|
|
return EraseInstFromFunction(CI);
|
|
}
|
|
}
|
|
|
|
// Scan down this block to see if there is another stack restore in the
|
|
// same block without an intervening call/alloca.
|
|
BasicBlock::iterator BI = II;
|
|
TerminatorInst *TI = II->getParent()->getTerminator();
|
|
bool CannotRemove = false;
|
|
for (++BI; &*BI != TI; ++BI) {
|
|
if (isa<AllocaInst>(BI) || isMalloc(BI)) {
|
|
CannotRemove = true;
|
|
break;
|
|
}
|
|
if (CallInst *BCI = dyn_cast<CallInst>(BI)) {
|
|
if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(BCI)) {
|
|
// If there is a stackrestore below this one, remove this one.
|
|
if (II->getIntrinsicID() == Intrinsic::stackrestore)
|
|
return EraseInstFromFunction(CI);
|
|
// Otherwise, ignore the intrinsic.
|
|
} else {
|
|
// If we found a non-intrinsic call, we can't remove the stack
|
|
// restore.
|
|
CannotRemove = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// If the stack restore is in a return/unwind block and if there are no
|
|
// allocas or calls between the restore and the return, nuke the restore.
|
|
if (!CannotRemove && (isa<ReturnInst>(TI) || isa<UnwindInst>(TI)))
|
|
return EraseInstFromFunction(CI);
|
|
break;
|
|
}
|
|
}
|
|
|
|
return visitCallSite(II);
|
|
}
|
|
|
|
// InvokeInst simplification
|
|
//
|
|
Instruction *InstCombiner::visitInvokeInst(InvokeInst &II) {
|
|
return visitCallSite(&II);
|
|
}
|
|
|
|
/// isSafeToEliminateVarargsCast - If this cast does not affect the value
|
|
/// passed through the varargs area, we can eliminate the use of the cast.
|
|
static bool isSafeToEliminateVarargsCast(const CallSite CS,
|
|
const CastInst * const CI,
|
|
const TargetData * const TD,
|
|
const int ix) {
|
|
if (!CI->isLosslessCast())
|
|
return false;
|
|
|
|
// The size of ByVal arguments is derived from the type, so we
|
|
// can't change to a type with a different size. If the size were
|
|
// passed explicitly we could avoid this check.
|
|
if (!CS.paramHasAttr(ix, Attribute::ByVal))
|
|
return true;
|
|
|
|
const Type* SrcTy =
|
|
cast<PointerType>(CI->getOperand(0)->getType())->getElementType();
|
|
const Type* DstTy = cast<PointerType>(CI->getType())->getElementType();
|
|
if (!SrcTy->isSized() || !DstTy->isSized())
|
|
return false;
|
|
if (!TD || TD->getTypeAllocSize(SrcTy) != TD->getTypeAllocSize(DstTy))
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
namespace {
|
|
class InstCombineFortifiedLibCalls : public SimplifyFortifiedLibCalls {
|
|
InstCombiner *IC;
|
|
protected:
|
|
void replaceCall(Value *With) {
|
|
NewInstruction = IC->ReplaceInstUsesWith(*CI, With);
|
|
}
|
|
bool isFoldable(unsigned SizeCIOp, unsigned SizeArgOp, bool isString) const {
|
|
if (ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(SizeCIOp))) {
|
|
if (SizeCI->isAllOnesValue())
|
|
return true;
|
|
if (isString)
|
|
return SizeCI->getZExtValue() >=
|
|
GetStringLength(CI->getOperand(SizeArgOp));
|
|
if (ConstantInt *Arg = dyn_cast<ConstantInt>(CI->getOperand(SizeArgOp)))
|
|
return SizeCI->getZExtValue() >= Arg->getZExtValue();
|
|
}
|
|
return false;
|
|
}
|
|
public:
|
|
InstCombineFortifiedLibCalls(InstCombiner *IC) : IC(IC), NewInstruction(0) { }
|
|
Instruction *NewInstruction;
|
|
};
|
|
} // end anonymous namespace
|
|
|
|
// Try to fold some different type of calls here.
|
|
// Currently we're only working with the checking functions, memcpy_chk,
|
|
// mempcpy_chk, memmove_chk, memset_chk, strcpy_chk, stpcpy_chk, strncpy_chk,
|
|
// strcat_chk and strncat_chk.
|
|
Instruction *InstCombiner::tryOptimizeCall(CallInst *CI, const TargetData *TD) {
|
|
if (CI->getCalledFunction() == 0) return 0;
|
|
|
|
InstCombineFortifiedLibCalls Simplifier(this);
|
|
Simplifier.fold(CI, TD);
|
|
return Simplifier.NewInstruction;
|
|
}
|
|
|
|
// visitCallSite - Improvements for call and invoke instructions.
|
|
//
|
|
Instruction *InstCombiner::visitCallSite(CallSite CS) {
|
|
bool Changed = false;
|
|
|
|
// If the callee is a constexpr cast of a function, attempt to move the cast
|
|
// to the arguments of the call/invoke.
|
|
if (transformConstExprCastCall(CS)) return 0;
|
|
|
|
Value *Callee = CS.getCalledValue();
|
|
|
|
if (Function *CalleeF = dyn_cast<Function>(Callee))
|
|
// If the call and callee calling conventions don't match, this call must
|
|
// be unreachable, as the call is undefined.
|
|
if (CalleeF->getCallingConv() != CS.getCallingConv() &&
|
|
// Only do this for calls to a function with a body. A prototype may
|
|
// not actually end up matching the implementation's calling conv for a
|
|
// variety of reasons (e.g. it may be written in assembly).
|
|
!CalleeF->isDeclaration()) {
|
|
Instruction *OldCall = CS.getInstruction();
|
|
new StoreInst(ConstantInt::getTrue(Callee->getContext()),
|
|
UndefValue::get(Type::getInt1PtrTy(Callee->getContext())),
|
|
OldCall);
|
|
// If OldCall dues not return void then replaceAllUsesWith undef.
|
|
// This allows ValueHandlers and custom metadata to adjust itself.
|
|
if (!OldCall->getType()->isVoidTy())
|
|
OldCall->replaceAllUsesWith(UndefValue::get(OldCall->getType()));
|
|
if (isa<CallInst>(OldCall))
|
|
return EraseInstFromFunction(*OldCall);
|
|
|
|
// We cannot remove an invoke, because it would change the CFG, just
|
|
// change the callee to a null pointer.
|
|
cast<InvokeInst>(OldCall)->setCalledFunction(
|
|
Constant::getNullValue(CalleeF->getType()));
|
|
return 0;
|
|
}
|
|
|
|
if (isa<ConstantPointerNull>(Callee) || isa<UndefValue>(Callee)) {
|
|
// This instruction is not reachable, just remove it. We insert a store to
|
|
// undef so that we know that this code is not reachable, despite the fact
|
|
// that we can't modify the CFG here.
|
|
new StoreInst(ConstantInt::getTrue(Callee->getContext()),
|
|
UndefValue::get(Type::getInt1PtrTy(Callee->getContext())),
|
|
CS.getInstruction());
|
|
|
|
// If CS does not return void then replaceAllUsesWith undef.
|
|
// This allows ValueHandlers and custom metadata to adjust itself.
|
|
if (!CS.getInstruction()->getType()->isVoidTy())
|
|
CS.getInstruction()->
|
|
replaceAllUsesWith(UndefValue::get(CS.getInstruction()->getType()));
|
|
|
|
if (InvokeInst *II = dyn_cast<InvokeInst>(CS.getInstruction())) {
|
|
// Don't break the CFG, insert a dummy cond branch.
|
|
BranchInst::Create(II->getNormalDest(), II->getUnwindDest(),
|
|
ConstantInt::getTrue(Callee->getContext()), II);
|
|
}
|
|
return EraseInstFromFunction(*CS.getInstruction());
|
|
}
|
|
|
|
if (BitCastInst *BC = dyn_cast<BitCastInst>(Callee))
|
|
if (IntrinsicInst *In = dyn_cast<IntrinsicInst>(BC->getOperand(0)))
|
|
if (In->getIntrinsicID() == Intrinsic::init_trampoline)
|
|
return transformCallThroughTrampoline(CS);
|
|
|
|
const PointerType *PTy = cast<PointerType>(Callee->getType());
|
|
const FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
|
|
if (FTy->isVarArg()) {
|
|
int ix = FTy->getNumParams() + (isa<InvokeInst>(Callee) ? 3 : 1);
|
|
// See if we can optimize any arguments passed through the varargs area of
|
|
// the call.
|
|
for (CallSite::arg_iterator I = CS.arg_begin()+FTy->getNumParams(),
|
|
E = CS.arg_end(); I != E; ++I, ++ix) {
|
|
CastInst *CI = dyn_cast<CastInst>(*I);
|
|
if (CI && isSafeToEliminateVarargsCast(CS, CI, TD, ix)) {
|
|
*I = CI->getOperand(0);
|
|
Changed = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (isa<InlineAsm>(Callee) && !CS.doesNotThrow()) {
|
|
// Inline asm calls cannot throw - mark them 'nounwind'.
|
|
CS.setDoesNotThrow();
|
|
Changed = true;
|
|
}
|
|
|
|
// Try to optimize the call if possible, we require TargetData for most of
|
|
// this. None of these calls are seen as possibly dead so go ahead and
|
|
// delete the instruction now.
|
|
if (CallInst *CI = dyn_cast<CallInst>(CS.getInstruction())) {
|
|
Instruction *I = tryOptimizeCall(CI, TD);
|
|
// If we changed something return the result, etc. Otherwise let
|
|
// the fallthrough check.
|
|
if (I) return EraseInstFromFunction(*I);
|
|
}
|
|
|
|
return Changed ? CS.getInstruction() : 0;
|
|
}
|
|
|
|
// transformConstExprCastCall - If the callee is a constexpr cast of a function,
|
|
// attempt to move the cast to the arguments of the call/invoke.
|
|
//
|
|
bool InstCombiner::transformConstExprCastCall(CallSite CS) {
|
|
if (!isa<ConstantExpr>(CS.getCalledValue())) return false;
|
|
ConstantExpr *CE = cast<ConstantExpr>(CS.getCalledValue());
|
|
if (CE->getOpcode() != Instruction::BitCast ||
|
|
!isa<Function>(CE->getOperand(0)))
|
|
return false;
|
|
Function *Callee = cast<Function>(CE->getOperand(0));
|
|
Instruction *Caller = CS.getInstruction();
|
|
const AttrListPtr &CallerPAL = CS.getAttributes();
|
|
|
|
// Okay, this is a cast from a function to a different type. Unless doing so
|
|
// would cause a type conversion of one of our arguments, change this call to
|
|
// be a direct call with arguments casted to the appropriate types.
|
|
//
|
|
const FunctionType *FT = Callee->getFunctionType();
|
|
const Type *OldRetTy = Caller->getType();
|
|
const Type *NewRetTy = FT->getReturnType();
|
|
|
|
if (NewRetTy->isStructTy())
|
|
return false; // TODO: Handle multiple return values.
|
|
|
|
// Check to see if we are changing the return type...
|
|
if (OldRetTy != NewRetTy) {
|
|
if (Callee->isDeclaration() &&
|
|
// Conversion is ok if changing from one pointer type to another or from
|
|
// a pointer to an integer of the same size.
|
|
!((OldRetTy->isPointerTy() || !TD ||
|
|
OldRetTy == TD->getIntPtrType(Caller->getContext())) &&
|
|
(NewRetTy->isPointerTy() || !TD ||
|
|
NewRetTy == TD->getIntPtrType(Caller->getContext()))))
|
|
return false; // Cannot transform this return value.
|
|
|
|
if (!Caller->use_empty() &&
|
|
// void -> non-void is handled specially
|
|
!NewRetTy->isVoidTy() && !CastInst::isCastable(NewRetTy, OldRetTy))
|
|
return false; // Cannot transform this return value.
|
|
|
|
if (!CallerPAL.isEmpty() && !Caller->use_empty()) {
|
|
Attributes RAttrs = CallerPAL.getRetAttributes();
|
|
if (RAttrs & Attribute::typeIncompatible(NewRetTy))
|
|
return false; // Attribute not compatible with transformed value.
|
|
}
|
|
|
|
// If the callsite is an invoke instruction, and the return value is used by
|
|
// a PHI node in a successor, we cannot change the return type of the call
|
|
// because there is no place to put the cast instruction (without breaking
|
|
// the critical edge). Bail out in this case.
|
|
if (!Caller->use_empty())
|
|
if (InvokeInst *II = dyn_cast<InvokeInst>(Caller))
|
|
for (Value::use_iterator UI = II->use_begin(), E = II->use_end();
|
|
UI != E; ++UI)
|
|
if (PHINode *PN = dyn_cast<PHINode>(*UI))
|
|
if (PN->getParent() == II->getNormalDest() ||
|
|
PN->getParent() == II->getUnwindDest())
|
|
return false;
|
|
}
|
|
|
|
unsigned NumActualArgs = unsigned(CS.arg_end()-CS.arg_begin());
|
|
unsigned NumCommonArgs = std::min(FT->getNumParams(), NumActualArgs);
|
|
|
|
CallSite::arg_iterator AI = CS.arg_begin();
|
|
for (unsigned i = 0, e = NumCommonArgs; i != e; ++i, ++AI) {
|
|
const Type *ParamTy = FT->getParamType(i);
|
|
const Type *ActTy = (*AI)->getType();
|
|
|
|
if (!CastInst::isCastable(ActTy, ParamTy))
|
|
return false; // Cannot transform this parameter value.
|
|
|
|
if (CallerPAL.getParamAttributes(i + 1)
|
|
& Attribute::typeIncompatible(ParamTy))
|
|
return false; // Attribute not compatible with transformed value.
|
|
|
|
// Converting from one pointer type to another or between a pointer and an
|
|
// integer of the same size is safe even if we do not have a body.
|
|
bool isConvertible = ActTy == ParamTy ||
|
|
(TD && ((ParamTy->isPointerTy() ||
|
|
ParamTy == TD->getIntPtrType(Caller->getContext())) &&
|
|
(ActTy->isPointerTy() ||
|
|
ActTy == TD->getIntPtrType(Caller->getContext()))));
|
|
if (Callee->isDeclaration() && !isConvertible) return false;
|
|
}
|
|
|
|
if (FT->getNumParams() < NumActualArgs && !FT->isVarArg() &&
|
|
Callee->isDeclaration())
|
|
return false; // Do not delete arguments unless we have a function body.
|
|
|
|
if (FT->getNumParams() < NumActualArgs && FT->isVarArg() &&
|
|
!CallerPAL.isEmpty())
|
|
// In this case we have more arguments than the new function type, but we
|
|
// won't be dropping them. Check that these extra arguments have attributes
|
|
// that are compatible with being a vararg call argument.
|
|
for (unsigned i = CallerPAL.getNumSlots(); i; --i) {
|
|
if (CallerPAL.getSlot(i - 1).Index <= FT->getNumParams())
|
|
break;
|
|
Attributes PAttrs = CallerPAL.getSlot(i - 1).Attrs;
|
|
if (PAttrs & Attribute::VarArgsIncompatible)
|
|
return false;
|
|
}
|
|
|
|
// Okay, we decided that this is a safe thing to do: go ahead and start
|
|
// inserting cast instructions as necessary...
|
|
std::vector<Value*> Args;
|
|
Args.reserve(NumActualArgs);
|
|
SmallVector<AttributeWithIndex, 8> attrVec;
|
|
attrVec.reserve(NumCommonArgs);
|
|
|
|
// Get any return attributes.
|
|
Attributes RAttrs = CallerPAL.getRetAttributes();
|
|
|
|
// If the return value is not being used, the type may not be compatible
|
|
// with the existing attributes. Wipe out any problematic attributes.
|
|
RAttrs &= ~Attribute::typeIncompatible(NewRetTy);
|
|
|
|
// Add the new return attributes.
|
|
if (RAttrs)
|
|
attrVec.push_back(AttributeWithIndex::get(0, RAttrs));
|
|
|
|
AI = CS.arg_begin();
|
|
for (unsigned i = 0; i != NumCommonArgs; ++i, ++AI) {
|
|
const Type *ParamTy = FT->getParamType(i);
|
|
if ((*AI)->getType() == ParamTy) {
|
|
Args.push_back(*AI);
|
|
} else {
|
|
Instruction::CastOps opcode = CastInst::getCastOpcode(*AI,
|
|
false, ParamTy, false);
|
|
Args.push_back(Builder->CreateCast(opcode, *AI, ParamTy, "tmp"));
|
|
}
|
|
|
|
// Add any parameter attributes.
|
|
if (Attributes PAttrs = CallerPAL.getParamAttributes(i + 1))
|
|
attrVec.push_back(AttributeWithIndex::get(i + 1, PAttrs));
|
|
}
|
|
|
|
// If the function takes more arguments than the call was taking, add them
|
|
// now.
|
|
for (unsigned i = NumCommonArgs; i != FT->getNumParams(); ++i)
|
|
Args.push_back(Constant::getNullValue(FT->getParamType(i)));
|
|
|
|
// If we are removing arguments to the function, emit an obnoxious warning.
|
|
if (FT->getNumParams() < NumActualArgs) {
|
|
if (!FT->isVarArg()) {
|
|
errs() << "WARNING: While resolving call to function '"
|
|
<< Callee->getName() << "' arguments were dropped!\n";
|
|
} else {
|
|
// Add all of the arguments in their promoted form to the arg list.
|
|
for (unsigned i = FT->getNumParams(); i != NumActualArgs; ++i, ++AI) {
|
|
const Type *PTy = getPromotedType((*AI)->getType());
|
|
if (PTy != (*AI)->getType()) {
|
|
// Must promote to pass through va_arg area!
|
|
Instruction::CastOps opcode =
|
|
CastInst::getCastOpcode(*AI, false, PTy, false);
|
|
Args.push_back(Builder->CreateCast(opcode, *AI, PTy, "tmp"));
|
|
} else {
|
|
Args.push_back(*AI);
|
|
}
|
|
|
|
// Add any parameter attributes.
|
|
if (Attributes PAttrs = CallerPAL.getParamAttributes(i + 1))
|
|
attrVec.push_back(AttributeWithIndex::get(i + 1, PAttrs));
|
|
}
|
|
}
|
|
}
|
|
|
|
if (Attributes FnAttrs = CallerPAL.getFnAttributes())
|
|
attrVec.push_back(AttributeWithIndex::get(~0, FnAttrs));
|
|
|
|
if (NewRetTy->isVoidTy())
|
|
Caller->setName(""); // Void type should not have a name.
|
|
|
|
const AttrListPtr &NewCallerPAL = AttrListPtr::get(attrVec.begin(),
|
|
attrVec.end());
|
|
|
|
Instruction *NC;
|
|
if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) {
|
|
NC = InvokeInst::Create(Callee, II->getNormalDest(), II->getUnwindDest(),
|
|
Args.begin(), Args.end(),
|
|
Caller->getName(), Caller);
|
|
cast<InvokeInst>(NC)->setCallingConv(II->getCallingConv());
|
|
cast<InvokeInst>(NC)->setAttributes(NewCallerPAL);
|
|
} else {
|
|
NC = CallInst::Create(Callee, Args.begin(), Args.end(),
|
|
Caller->getName(), Caller);
|
|
CallInst *CI = cast<CallInst>(Caller);
|
|
if (CI->isTailCall())
|
|
cast<CallInst>(NC)->setTailCall();
|
|
cast<CallInst>(NC)->setCallingConv(CI->getCallingConv());
|
|
cast<CallInst>(NC)->setAttributes(NewCallerPAL);
|
|
}
|
|
|
|
// Insert a cast of the return type as necessary.
|
|
Value *NV = NC;
|
|
if (OldRetTy != NV->getType() && !Caller->use_empty()) {
|
|
if (!NV->getType()->isVoidTy()) {
|
|
Instruction::CastOps opcode = CastInst::getCastOpcode(NC, false,
|
|
OldRetTy, false);
|
|
NV = NC = CastInst::Create(opcode, NC, OldRetTy, "tmp");
|
|
|
|
// If this is an invoke instruction, we should insert it after the first
|
|
// non-phi, instruction in the normal successor block.
|
|
if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) {
|
|
BasicBlock::iterator I = II->getNormalDest()->getFirstNonPHI();
|
|
InsertNewInstBefore(NC, *I);
|
|
} else {
|
|
// Otherwise, it's a call, just insert cast right after the call instr
|
|
InsertNewInstBefore(NC, *Caller);
|
|
}
|
|
Worklist.AddUsersToWorkList(*Caller);
|
|
} else {
|
|
NV = UndefValue::get(Caller->getType());
|
|
}
|
|
}
|
|
|
|
|
|
if (!Caller->use_empty())
|
|
Caller->replaceAllUsesWith(NV);
|
|
|
|
EraseInstFromFunction(*Caller);
|
|
return true;
|
|
}
|
|
|
|
// transformCallThroughTrampoline - Turn a call to a function created by the
|
|
// init_trampoline intrinsic into a direct call to the underlying function.
|
|
//
|
|
Instruction *InstCombiner::transformCallThroughTrampoline(CallSite CS) {
|
|
Value *Callee = CS.getCalledValue();
|
|
const PointerType *PTy = cast<PointerType>(Callee->getType());
|
|
const FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
|
|
const AttrListPtr &Attrs = CS.getAttributes();
|
|
|
|
// If the call already has the 'nest' attribute somewhere then give up -
|
|
// otherwise 'nest' would occur twice after splicing in the chain.
|
|
if (Attrs.hasAttrSomewhere(Attribute::Nest))
|
|
return 0;
|
|
|
|
IntrinsicInst *Tramp =
|
|
cast<IntrinsicInst>(cast<BitCastInst>(Callee)->getOperand(0));
|
|
|
|
Function *NestF = cast<Function>(Tramp->getOperand(1)->stripPointerCasts());
|
|
const PointerType *NestFPTy = cast<PointerType>(NestF->getType());
|
|
const FunctionType *NestFTy = cast<FunctionType>(NestFPTy->getElementType());
|
|
|
|
const AttrListPtr &NestAttrs = NestF->getAttributes();
|
|
if (!NestAttrs.isEmpty()) {
|
|
unsigned NestIdx = 1;
|
|
const Type *NestTy = 0;
|
|
Attributes NestAttr = Attribute::None;
|
|
|
|
// Look for a parameter marked with the 'nest' attribute.
|
|
for (FunctionType::param_iterator I = NestFTy->param_begin(),
|
|
E = NestFTy->param_end(); I != E; ++NestIdx, ++I)
|
|
if (NestAttrs.paramHasAttr(NestIdx, Attribute::Nest)) {
|
|
// Record the parameter type and any other attributes.
|
|
NestTy = *I;
|
|
NestAttr = NestAttrs.getParamAttributes(NestIdx);
|
|
break;
|
|
}
|
|
|
|
if (NestTy) {
|
|
Instruction *Caller = CS.getInstruction();
|
|
std::vector<Value*> NewArgs;
|
|
NewArgs.reserve(unsigned(CS.arg_end()-CS.arg_begin())+1);
|
|
|
|
SmallVector<AttributeWithIndex, 8> NewAttrs;
|
|
NewAttrs.reserve(Attrs.getNumSlots() + 1);
|
|
|
|
// Insert the nest argument into the call argument list, which may
|
|
// mean appending it. Likewise for attributes.
|
|
|
|
// Add any result attributes.
|
|
if (Attributes Attr = Attrs.getRetAttributes())
|
|
NewAttrs.push_back(AttributeWithIndex::get(0, Attr));
|
|
|
|
{
|
|
unsigned Idx = 1;
|
|
CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end();
|
|
do {
|
|
if (Idx == NestIdx) {
|
|
// Add the chain argument and attributes.
|
|
Value *NestVal = Tramp->getOperand(2);
|
|
if (NestVal->getType() != NestTy)
|
|
NestVal = new BitCastInst(NestVal, NestTy, "nest", Caller);
|
|
NewArgs.push_back(NestVal);
|
|
NewAttrs.push_back(AttributeWithIndex::get(NestIdx, NestAttr));
|
|
}
|
|
|
|
if (I == E)
|
|
break;
|
|
|
|
// Add the original argument and attributes.
|
|
NewArgs.push_back(*I);
|
|
if (Attributes Attr = Attrs.getParamAttributes(Idx))
|
|
NewAttrs.push_back
|
|
(AttributeWithIndex::get(Idx + (Idx >= NestIdx), Attr));
|
|
|
|
++Idx, ++I;
|
|
} while (1);
|
|
}
|
|
|
|
// Add any function attributes.
|
|
if (Attributes Attr = Attrs.getFnAttributes())
|
|
NewAttrs.push_back(AttributeWithIndex::get(~0, Attr));
|
|
|
|
// The trampoline may have been bitcast to a bogus type (FTy).
|
|
// Handle this by synthesizing a new function type, equal to FTy
|
|
// with the chain parameter inserted.
|
|
|
|
std::vector<const Type*> NewTypes;
|
|
NewTypes.reserve(FTy->getNumParams()+1);
|
|
|
|
// Insert the chain's type into the list of parameter types, which may
|
|
// mean appending it.
|
|
{
|
|
unsigned Idx = 1;
|
|
FunctionType::param_iterator I = FTy->param_begin(),
|
|
E = FTy->param_end();
|
|
|
|
do {
|
|
if (Idx == NestIdx)
|
|
// Add the chain's type.
|
|
NewTypes.push_back(NestTy);
|
|
|
|
if (I == E)
|
|
break;
|
|
|
|
// Add the original type.
|
|
NewTypes.push_back(*I);
|
|
|
|
++Idx, ++I;
|
|
} while (1);
|
|
}
|
|
|
|
// Replace the trampoline call with a direct call. Let the generic
|
|
// code sort out any function type mismatches.
|
|
FunctionType *NewFTy = FunctionType::get(FTy->getReturnType(), NewTypes,
|
|
FTy->isVarArg());
|
|
Constant *NewCallee =
|
|
NestF->getType() == PointerType::getUnqual(NewFTy) ?
|
|
NestF : ConstantExpr::getBitCast(NestF,
|
|
PointerType::getUnqual(NewFTy));
|
|
const AttrListPtr &NewPAL = AttrListPtr::get(NewAttrs.begin(),
|
|
NewAttrs.end());
|
|
|
|
Instruction *NewCaller;
|
|
if (InvokeInst *II = dyn_cast<InvokeInst>(Caller)) {
|
|
NewCaller = InvokeInst::Create(NewCallee,
|
|
II->getNormalDest(), II->getUnwindDest(),
|
|
NewArgs.begin(), NewArgs.end(),
|
|
Caller->getName(), Caller);
|
|
cast<InvokeInst>(NewCaller)->setCallingConv(II->getCallingConv());
|
|
cast<InvokeInst>(NewCaller)->setAttributes(NewPAL);
|
|
} else {
|
|
NewCaller = CallInst::Create(NewCallee, NewArgs.begin(), NewArgs.end(),
|
|
Caller->getName(), Caller);
|
|
if (cast<CallInst>(Caller)->isTailCall())
|
|
cast<CallInst>(NewCaller)->setTailCall();
|
|
cast<CallInst>(NewCaller)->
|
|
setCallingConv(cast<CallInst>(Caller)->getCallingConv());
|
|
cast<CallInst>(NewCaller)->setAttributes(NewPAL);
|
|
}
|
|
if (!Caller->getType()->isVoidTy())
|
|
Caller->replaceAllUsesWith(NewCaller);
|
|
Caller->eraseFromParent();
|
|
Worklist.Remove(Caller);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
// Replace the trampoline call with a direct call. Since there is no 'nest'
|
|
// parameter, there is no need to adjust the argument list. Let the generic
|
|
// code sort out any function type mismatches.
|
|
Constant *NewCallee =
|
|
NestF->getType() == PTy ? NestF :
|
|
ConstantExpr::getBitCast(NestF, PTy);
|
|
CS.setCalledFunction(NewCallee);
|
|
return CS.getInstruction();
|
|
}
|
|
|