Revert "Revert r206045, "Fix shift by constants for vector.""
Fix cases where the Value itself is used, and not the constant value.
llvm-svn: 206214
diff --git a/llvm/lib/Transforms/InstCombine/InstCombine.h b/llvm/lib/Transforms/InstCombine/InstCombine.h
index 822e146..4ee2f59 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombine.h
+++ b/llvm/lib/Transforms/InstCombine/InstCombine.h
@@ -171,7 +171,7 @@
ICmpInst::Predicate Pred);
Instruction *FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
ICmpInst::Predicate Cond, Instruction &I);
- Instruction *FoldShiftByConstant(Value *Op0, ConstantInt *Op1,
+ Instruction *FoldShiftByConstant(Value *Op0, Constant *Op1,
BinaryOperator &I);
Instruction *commonCastTransforms(CastInst &CI);
Instruction *commonPointerCastTransforms(CastInst &CI);
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
index e873c1d..f2e2cb3 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp
@@ -33,7 +33,7 @@
if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
- if (ConstantInt *CUI = dyn_cast<ConstantInt>(Op1))
+ if (Constant *CUI = dyn_cast<Constant>(Op1))
if (Instruction *Res = FoldShiftByConstant(Op0, CUI, I))
return Res;
@@ -309,20 +309,30 @@
-Instruction *InstCombiner::FoldShiftByConstant(Value *Op0, ConstantInt *Op1,
+Instruction *InstCombiner::FoldShiftByConstant(Value *Op0, Constant *Op1,
BinaryOperator &I) {
bool isLeftShift = I.getOpcode() == Instruction::Shl;
+ ConstantInt *COp1 = nullptr;
+ if (ConstantDataVector *CV = dyn_cast<ConstantDataVector>(Op1))
+ COp1 = dyn_cast_or_null<ConstantInt>(CV->getSplatValue());
+ else if (ConstantVector *CV = dyn_cast<ConstantVector>(Op1))
+ COp1 = dyn_cast_or_null<ConstantInt>(CV->getSplatValue());
+ else
+ COp1 = dyn_cast<ConstantInt>(Op1);
+
+ if (!COp1)
+ return nullptr;
// See if we can propagate this shift into the input, this covers the trivial
// cast of lshr(shl(x,c1),c2) as well as other more complex cases.
if (I.getOpcode() != Instruction::AShr &&
- CanEvaluateShifted(Op0, Op1->getZExtValue(), isLeftShift, *this)) {
+ CanEvaluateShifted(Op0, COp1->getZExtValue(), isLeftShift, *this)) {
DEBUG(dbgs() << "ICE: GetShiftedValue propagating shift through expression"
" to eliminate shift:\n IN: " << *Op0 << "\n SH: " << I <<"\n");
return ReplaceInstUsesWith(I,
- GetShiftedValue(Op0, Op1->getZExtValue(), isLeftShift, *this));
+ GetShiftedValue(Op0, COp1->getZExtValue(), isLeftShift, *this));
}
@@ -333,7 +343,7 @@
// shl i32 X, 32 = 0 and srl i8 Y, 9 = 0, ... just don't eliminate
// a signed shift.
//
- if (Op1->uge(TypeBits)) {
+ if (COp1->uge(TypeBits)) {
if (I.getOpcode() != Instruction::AShr)
return ReplaceInstUsesWith(I, Constant::getNullValue(Op0->getType()));
// ashr i32 X, 32 --> ashr i32 X, 31
@@ -367,7 +377,7 @@
if (TrOp && I.isLogicalShift() && TrOp->isShift() &&
isa<ConstantInt>(TrOp->getOperand(1))) {
// Okay, we'll do this xform. Make the shift of shift.
- Constant *ShAmt = ConstantExpr::getZExt(Op1, TrOp->getType());
+ Constant *ShAmt = ConstantExpr::getZExt(COp1, TrOp->getType());
// (shift2 (shift1 & 0x00FF), c2)
Value *NSh = Builder->CreateBinOp(I.getOpcode(), TrOp, ShAmt,I.getName());
@@ -384,10 +394,10 @@
// shift. We know that it is a logical shift by a constant, so adjust the
// mask as appropriate.
if (I.getOpcode() == Instruction::Shl)
- MaskV <<= Op1->getZExtValue();
+ MaskV <<= COp1->getZExtValue();
else {
assert(I.getOpcode() == Instruction::LShr && "Unknown logical shift");
- MaskV = MaskV.lshr(Op1->getZExtValue());
+ MaskV = MaskV.lshr(COp1->getZExtValue());
}
// shift1 & 0x00FF
@@ -421,9 +431,13 @@
// (X + (Y << C))
Value *X = Builder->CreateBinOp(Op0BO->getOpcode(), YS, V1,
Op0BO->getOperand(1)->getName());
- uint32_t Op1Val = Op1->getLimitedValue(TypeBits);
- return BinaryOperator::CreateAnd(X, ConstantInt::get(I.getContext(),
- APInt::getHighBitsSet(TypeBits, TypeBits-Op1Val)));
+ uint32_t Op1Val = COp1->getLimitedValue(TypeBits);
+
+ APInt Bits = APInt::getHighBitsSet(TypeBits, TypeBits - Op1Val);
+ Constant *Mask = ConstantInt::get(I.getContext(), Bits);
+ if (VectorType *VT = dyn_cast<VectorType>(X->getType()))
+ Mask = ConstantVector::getSplat(VT->getNumElements(), Mask);
+ return BinaryOperator::CreateAnd(X, Mask);
}
// Turn (Y + ((X >> C) & CC)) << C -> ((X & (CC << C)) + (Y << C))
@@ -453,9 +467,13 @@
// (X + (Y << C))
Value *X = Builder->CreateBinOp(Op0BO->getOpcode(), V1, YS,
Op0BO->getOperand(0)->getName());
- uint32_t Op1Val = Op1->getLimitedValue(TypeBits);
- return BinaryOperator::CreateAnd(X, ConstantInt::get(I.getContext(),
- APInt::getHighBitsSet(TypeBits, TypeBits-Op1Val)));
+ uint32_t Op1Val = COp1->getLimitedValue(TypeBits);
+
+ APInt Bits = APInt::getHighBitsSet(TypeBits, TypeBits - Op1Val);
+ Constant *Mask = ConstantInt::get(I.getContext(), Bits);
+ if (VectorType *VT = dyn_cast<VectorType>(X->getType()))
+ Mask = ConstantVector::getSplat(VT->getNumElements(), Mask);
+ return BinaryOperator::CreateAnd(X, Mask);
}
// Turn (((X >> C)&CC) + Y) << C -> (X + (Y << C)) & (CC << C)
@@ -541,7 +559,7 @@
ConstantInt *ShiftAmt1C = cast<ConstantInt>(ShiftOp->getOperand(1));
uint32_t ShiftAmt1 = ShiftAmt1C->getLimitedValue(TypeBits);
- uint32_t ShiftAmt2 = Op1->getLimitedValue(TypeBits);
+ uint32_t ShiftAmt2 = COp1->getLimitedValue(TypeBits);
assert(ShiftAmt2 != 0 && "Should have been simplified earlier");
if (ShiftAmt1 == 0) return 0; // Will be simplified in the future.
Value *X = ShiftOp->getOperand(0);