// This requires TargetData to get the alloca alignment and size information.
if (!TD) return 0;
+ // Insist that the amount-to-allocate not overflow.
+ OverflowingBinaryOperator *OBI =
+ dyn_cast<OverflowingBinaryOperator>(AI.getOperand(0));
+ if (OBI && !(OBI->hasNoSignedWrap() || OBI->hasNoUnsignedWrap())) return 0;
+
const PointerType *PTy = cast<PointerType>(CI.getType());
BuilderTy AllocaBuilder(*Builder);
// If the allocation has multiple uses, only promote it if we are strictly
// increasing the alignment of the resultant allocation. If we keep it the
- // same, we open the door to infinite loops of various kinds. (A reference
- // from a dbg.declare doesn't count as a use for this purpose.)
- if (!AI.hasOneUse() && !hasOneUsePlusDeclare(&AI) &&
- CastElTyAlign == AllocElTyAlign) return 0;
+ // same, we open the door to infinite loops of various kinds.
+ if (!AI.hasOneUse() && CastElTyAlign == AllocElTyAlign) return 0;
uint64_t AllocElTySize = TD->getTypeAllocSize(AllocElTy);
uint64_t CastElTySize = TD->getTypeAllocSize(CastElTy);
New->setAlignment(AI.getAlignment());
New->takeName(&AI);
- // If the allocation has one real use plus a dbg.declare, just remove the
- // declare.
- if (DbgDeclareInst *DI = hasOneUsePlusDeclare(&AI)) {
- EraseInstFromFunction(*(Instruction*)DI);
- }
// If the allocation has multiple real uses, insert a cast and change all
// things that used it to use the new cast. This will also hack on CI, but it
// will die soon.
- else if (!AI.hasOneUse()) {
+ if (!AI.hasOneUse()) {
// New is the allocation instruction, pointer typed. AI is the original
// allocation instruction, also pointer typed. Thus, cast to use is BitCast.
Value *NewCast = AllocaBuilder.CreateBitCast(New, AI.getType(), "tmpcast");
- AI.replaceAllUsesWith(NewCast);
+ ReplaceInstUsesWith(AI, NewCast);
}
return ReplaceInstUsesWith(CI, New);
}
}
case Instruction::PHI: {
PHINode *OPN = cast<PHINode>(I);
- PHINode *NPN = PHINode::Create(Ty);
+ PHINode *NPN = PHINode::Create(Ty, OPN->getNumIncomingValues());
for (unsigned i = 0, e = OPN->getNumIncomingValues(); i != e; ++i) {
Value *V =EvaluateInDifferentType(OPN->getIncomingValue(i), Ty, isSigned);
NPN->addIncoming(V, OPN->getIncomingBlock(i));
}
Res->takeName(I);
- return InsertNewInstBefore(Res, *I);
+ return InsertNewInstWith(Res, *I);
}
// Transform trunc(lshr (zext A), Cst) to eliminate one type conversion.
Value *A = 0; ConstantInt *Cst = 0;
- if (match(Src, m_LShr(m_ZExt(m_Value(A)), m_ConstantInt(Cst))) &&
- Src->hasOneUse()) {
+ if (Src->hasOneUse() &&
+ match(Src, m_LShr(m_ZExt(m_Value(A)), m_ConstantInt(Cst)))) {
// We have three types to worry about here, the type of A, the source of
// the truncate (MidSize), and the destination of the truncate. We know that
// ASize < MidSize and MidSize > ResultSize, but don't know the relation
Shift->takeName(Src);
return CastInst::CreateIntegerCast(Shift, CI.getType(), false);
}
+
+ // Transform "trunc (and X, cst)" -> "and (trunc X), cst" so long as the dest
+ // type isn't non-native.
+ if (Src->hasOneUse() && isa<IntegerType>(Src->getType()) &&
+ ShouldChangeType(Src->getType(), CI.getType()) &&
+ match(Src, m_And(m_Value(A), m_ConstantInt(Cst)))) {
+ Value *NewTrunc = Builder->CreateTrunc(A, CI.getType(), A->getName()+".tr");
+ return BinaryOperator::CreateAnd(NewTrunc,
+ ConstantExpr::getTrunc(Cst, CI.getType()));
+ }
return 0;
}
return 0;
}
+/// transformSExtICmp - Transform (sext icmp) to bitwise / integer operations
+/// in order to eliminate the icmp.
+Instruction *InstCombiner::transformSExtICmp(ICmpInst *ICI, Instruction &CI) {
+ Value *Op0 = ICI->getOperand(0), *Op1 = ICI->getOperand(1);
+ ICmpInst::Predicate Pred = ICI->getPredicate();
+
+ if (ConstantInt *Op1C = dyn_cast<ConstantInt>(Op1)) {
+ // (x <s 0) ? -1 : 0 -> ashr x, 31 -> all ones if negative
+ // (x >s -1) ? -1 : 0 -> not (ashr x, 31) -> all ones if positive
+ if ((Pred == ICmpInst::ICMP_SLT && Op1C->isZero()) ||
+ (Pred == ICmpInst::ICMP_SGT && Op1C->isAllOnesValue())) {
+
+ Value *Sh = ConstantInt::get(Op0->getType(),
+ Op0->getType()->getScalarSizeInBits()-1);
+ Value *In = Builder->CreateAShr(Op0, Sh, Op0->getName()+".lobit");
+ if (In->getType() != CI.getType())
+ In = Builder->CreateIntCast(In, CI.getType(), true/*SExt*/, "tmp");
+
+ if (Pred == ICmpInst::ICMP_SGT)
+ In = Builder->CreateNot(In, In->getName()+".not");
+ return ReplaceInstUsesWith(CI, In);
+ }
+
+ // If we know that only one bit of the LHS of the icmp can be set and we
+ // have an equality comparison with zero or a power of 2, we can transform
+ // the icmp and sext into bitwise/integer operations.
+ if (ICI->hasOneUse() &&
+ ICI->isEquality() && (Op1C->isZero() || Op1C->getValue().isPowerOf2())){
+ unsigned BitWidth = Op1C->getType()->getBitWidth();
+ APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
+ APInt TypeMask(APInt::getAllOnesValue(BitWidth));
+ ComputeMaskedBits(Op0, TypeMask, KnownZero, KnownOne);
+
+ APInt KnownZeroMask(~KnownZero);
+ if (KnownZeroMask.isPowerOf2()) {
+ Value *In = ICI->getOperand(0);
+
+ // If the icmp tests for a known zero bit we can constant fold it.
+ if (!Op1C->isZero() && Op1C->getValue() != KnownZeroMask) {
+ Value *V = Pred == ICmpInst::ICMP_NE ?
+ ConstantInt::getAllOnesValue(CI.getType()) :
+ ConstantInt::getNullValue(CI.getType());
+ return ReplaceInstUsesWith(CI, V);
+ }
+
+ if (!Op1C->isZero() == (Pred == ICmpInst::ICMP_NE)) {
+ // sext ((x & 2^n) == 0) -> (x >> n) - 1
+ // sext ((x & 2^n) != 2^n) -> (x >> n) - 1
+ unsigned ShiftAmt = KnownZeroMask.countTrailingZeros();
+ // Perform a right shift to place the desired bit in the LSB.
+ if (ShiftAmt)
+ In = Builder->CreateLShr(In,
+ ConstantInt::get(In->getType(), ShiftAmt));
+
+ // At this point "In" is either 1 or 0. Subtract 1 to turn
+ // {1, 0} -> {0, -1}.
+ In = Builder->CreateAdd(In,
+ ConstantInt::getAllOnesValue(In->getType()),
+ "sext");
+ } else {
+ // sext ((x & 2^n) != 0) -> (x << bitwidth-n) a>> bitwidth-1
+ // sext ((x & 2^n) == 2^n) -> (x << bitwidth-n) a>> bitwidth-1
+ unsigned ShiftAmt = KnownZeroMask.countLeadingZeros();
+ // Perform a left shift to place the desired bit in the MSB.
+ if (ShiftAmt)
+ In = Builder->CreateShl(In,
+ ConstantInt::get(In->getType(), ShiftAmt));
+
+ // Distribute the bit over the whole bit width.
+ In = Builder->CreateAShr(In, ConstantInt::get(In->getType(),
+ BitWidth - 1), "sext");
+ }
+
+ if (CI.getType() == In->getType())
+ return ReplaceInstUsesWith(CI, In);
+ return CastInst::CreateIntegerCast(In, CI.getType(), true/*SExt*/);
+ }
+ }
+ }
+
+ // vector (x <s 0) ? -1 : 0 -> ashr x, 31 -> all ones if signed.
+ if (const VectorType *VTy = dyn_cast<VectorType>(CI.getType())) {
+ if (Pred == ICmpInst::ICMP_SLT && match(Op1, m_Zero()) &&
+ Op0->getType() == CI.getType()) {
+ const Type *EltTy = VTy->getElementType();
+
+ // splat the shift constant to a constant vector.
+ Constant *VSh = ConstantInt::get(VTy, EltTy->getScalarSizeInBits()-1);
+ Value *In = Builder->CreateAShr(Op0, VSh, Op0->getName()+".lobit");
+ return ReplaceInstUsesWith(CI, In);
+ }
+ }
+
+ return 0;
+}
+
/// CanEvaluateSExtd - Return true if we can take the specified value
/// and return it as type Ty without inserting any new casts and without
/// changing the value of the common low bits. This is used by code that tries
Value *Res = Builder->CreateShl(TI->getOperand(0), ShAmt, "sext");
return BinaryOperator::CreateAShr(Res, ShAmt);
}
-
-
- // (x <s 0) ? -1 : 0 -> ashr x, 31 -> all ones if signed
- // (x >s -1) ? -1 : 0 -> ashr x, 31 -> all ones if not signed
- {
- ICmpInst::Predicate Pred; Value *CmpLHS; ConstantInt *CmpRHS;
- if (match(Src, m_ICmp(Pred, m_Value(CmpLHS), m_ConstantInt(CmpRHS)))) {
- // sext (x <s 0) to i32 --> x>>s31 true if signbit set.
- // sext (x >s -1) to i32 --> (x>>s31)^-1 true if signbit clear.
- if ((Pred == ICmpInst::ICMP_SLT && CmpRHS->isZero()) ||
- (Pred == ICmpInst::ICMP_SGT && CmpRHS->isAllOnesValue())) {
- Value *Sh = ConstantInt::get(CmpLHS->getType(),
- CmpLHS->getType()->getScalarSizeInBits()-1);
- Value *In = Builder->CreateAShr(CmpLHS, Sh, CmpLHS->getName()+".lobit");
- if (In->getType() != CI.getType())
- In = Builder->CreateIntCast(In, CI.getType(), true/*SExt*/, "tmp");
-
- if (Pred == ICmpInst::ICMP_SGT)
- In = Builder->CreateNot(In, In->getName()+".not");
- return ReplaceInstUsesWith(CI, In);
- }
- }
- }
-
-
+
+ if (ICmpInst *ICI = dyn_cast<ICmpInst>(Src))
+ return transformSExtICmp(ICI, CI);
+
// If the input is a shl/ashr pair of a same constant, then this is a sign
// extension from a smaller value. If we could trust arbitrary bitwidth
// integers, we could turn this into a truncate to the smaller bit and then
Arg->getOperand(0)->getType()->isFloatTy()) {
Function *Callee = Call->getCalledFunction();
Module *M = CI.getParent()->getParent()->getParent();
- Constant* SqrtfFunc = M->getOrInsertFunction("sqrtf",
+ Constant *SqrtfFunc = M->getOrInsertFunction("sqrtf",
Callee->getAttributes(),
Builder->getFloatTy(),
Builder->getFloatTy(),
CallInst *ret = CallInst::Create(SqrtfFunc, Arg->getOperand(0),
"sqrtfcall");
ret->setAttributes(Callee->getAttributes());
+
+
+ // Remove the old Call. With -fmath-errno, it won't get marked readnone.
+ ReplaceInstUsesWith(*Call, UndefValue::get(Call->getType()));
+ EraseInstFromFunction(*Call);
return ret;
}
}
ConstantInt::get(Int32Ty, SrcElts));
}
- Constant *Mask = ConstantVector::get(ShuffleMask.data(), ShuffleMask.size());
- return new ShuffleVectorInst(InVal, V2, Mask);
+ return new ShuffleVectorInst(InVal, V2, ConstantVector::get(ShuffleMask));
}
static bool isMultipleOfTypeSize(unsigned Value, const Type *Ty) {
// If we found a path from the src to dest, create the getelementptr now.
if (SrcElTy == DstElTy) {
SmallVector<Value*, 8> Idxs(NumZeros+1, ZeroUInt);
- return GetElementPtrInst::CreateInBounds(Src, Idxs.begin(), Idxs.end(),"",
- ((Instruction*)NULL));
+ return GetElementPtrInst::CreateInBounds(Src, Idxs.begin(), Idxs.end());
}
}
projects / oota-llvm.git / blobdiff