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Diffstat (limited to 'lib/Transforms/InstCombine/InstructionCombining.cpp')
-rw-r--r--lib/Transforms/InstCombine/InstructionCombining.cpp43
1 files changed, 13 insertions, 30 deletions
diff --git a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp
index 81f2d9fa179f9..4729c79ca4c3d 100644
--- a/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -60,6 +60,7 @@
#include "llvm/IR/ValueHandle.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
+#include "llvm/Support/KnownBits.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/Local.h"
@@ -641,14 +642,6 @@ Value *InstCombiner::SimplifyUsingDistributiveLaws(BinaryOperator &I) {
if (Value *R = SimplifyBinOp(TopLevelOpcode, B, C, DL)) {
// They do! Return "L op' R".
++NumExpand;
- // If "L op' R" equals "A op' B" then "L op' R" is just the LHS.
- if ((L == A && R == B) ||
- (Instruction::isCommutative(InnerOpcode) && L == B && R == A))
- return Op0;
- // Otherwise return "L op' R" if it simplifies.
- if (Value *V = SimplifyBinOp(InnerOpcode, L, R, DL))
- return V;
- // Otherwise, create a new instruction.
C = Builder->CreateBinOp(InnerOpcode, L, R);
C->takeName(&I);
return C;
@@ -666,14 +659,6 @@ Value *InstCombiner::SimplifyUsingDistributiveLaws(BinaryOperator &I) {
if (Value *R = SimplifyBinOp(TopLevelOpcode, A, C, DL)) {
// They do! Return "L op' R".
++NumExpand;
- // If "L op' R" equals "B op' C" then "L op' R" is just the RHS.
- if ((L == B && R == C) ||
- (Instruction::isCommutative(InnerOpcode) && L == C && R == B))
- return Op1;
- // Otherwise return "L op' R" if it simplifies.
- if (Value *V = SimplifyBinOp(InnerOpcode, L, R, DL))
- return V;
- // Otherwise, create a new instruction.
A = Builder->CreateBinOp(InnerOpcode, L, R);
A->takeName(&I);
return A;
@@ -2196,11 +2181,10 @@ Instruction *InstCombiner::visitReturnInst(ReturnInst &RI) {
// There might be assume intrinsics dominating this return that completely
// determine the value. If so, constant fold it.
- unsigned BitWidth = VTy->getPrimitiveSizeInBits();
- APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
- computeKnownBits(ResultOp, KnownZero, KnownOne, 0, &RI);
- if ((KnownZero|KnownOne).isAllOnesValue())
- RI.setOperand(0, Constant::getIntegerValue(VTy, KnownOne));
+ KnownBits Known(VTy->getPrimitiveSizeInBits());
+ computeKnownBits(ResultOp, Known, 0, &RI);
+ if ((Known.Zero|Known.One).isAllOnesValue())
+ RI.setOperand(0, Constant::getIntegerValue(VTy, Known.One));
return nullptr;
}
@@ -2279,10 +2263,10 @@ Instruction *InstCombiner::visitSwitchInst(SwitchInst &SI) {
}
unsigned BitWidth = cast<IntegerType>(Cond->getType())->getBitWidth();
- APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
- computeKnownBits(Cond, KnownZero, KnownOne, 0, &SI);
- unsigned LeadingKnownZeros = KnownZero.countLeadingOnes();
- unsigned LeadingKnownOnes = KnownOne.countLeadingOnes();
+ KnownBits Known(BitWidth);
+ computeKnownBits(Cond, Known, 0, &SI);
+ unsigned LeadingKnownZeros = Known.Zero.countLeadingOnes();
+ unsigned LeadingKnownOnes = Known.One.countLeadingOnes();
// Compute the number of leading bits we can ignore.
// TODO: A better way to determine this would use ComputeNumSignBits().
@@ -2879,11 +2863,10 @@ bool InstCombiner::run() {
Type *Ty = I->getType();
if (ExpensiveCombines && !I->use_empty() && Ty->isIntOrIntVectorTy()) {
unsigned BitWidth = Ty->getScalarSizeInBits();
- APInt KnownZero(BitWidth, 0);
- APInt KnownOne(BitWidth, 0);
- computeKnownBits(I, KnownZero, KnownOne, /*Depth*/0, I);
- if ((KnownZero | KnownOne).isAllOnesValue()) {
- Constant *C = ConstantInt::get(Ty, KnownOne);
+ KnownBits Known(BitWidth);
+ computeKnownBits(I, Known, /*Depth*/0, I);
+ if ((Known.Zero | Known.One).isAllOnesValue()) {
+ Constant *C = ConstantInt::get(Ty, Known.One);
DEBUG(dbgs() << "IC: ConstFold (all bits known) to: " << *C <<
" from: " << *I << '\n');