This shouldn't happen in practice because the icmp would be a constant.
Add a check so we don't miscompile code if something goes wrong.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130446
91177308-0d34-0410-b5e6-
96231b3b80d8
// (trunc x) == C1 & (and x, CA) == C2 -> (and x, CA|CMAX) == C1|C2
// where CMAX is the all ones value for the truncated type,
// (trunc x) == C1 & (and x, CA) == C2 -> (and x, CA|CMAX) == C1|C2
// where CMAX is the all ones value for the truncated type,
- // iff the lower bits of CA are zero.
+ // iff the lower bits of C2 and CA are zero.
if (LHSCC == RHSCC && ICmpInst::isEquality(LHSCC) &&
LHS->hasOneUse() && RHS->hasOneUse()) {
Value *V;
if (LHSCC == RHSCC && ICmpInst::isEquality(LHSCC) &&
LHS->hasOneUse() && RHS->hasOneUse()) {
Value *V;
// Check that the low bits are zero.
APInt Low = APInt::getLowBitsSet(BigBitSize, SmallBitSize);
// Check that the low bits are zero.
APInt Low = APInt::getLowBitsSet(BigBitSize, SmallBitSize);
- if ((Low & AndCst->getValue()) == 0) {
+ if ((Low & AndCst->getValue()) == 0 && (Low & BigCst->getValue()) == 0) {
Value *NewAnd = Builder->CreateAnd(V, Low | AndCst->getValue());
APInt N = SmallCst->getValue().zext(BigBitSize) | BigCst->getValue();
Value *NewVal = ConstantInt::get(AndCst->getType()->getContext(), N);
Value *NewAnd = Builder->CreateAnd(V, Low | AndCst->getValue());
APInt N = SmallCst->getValue().zext(BigBitSize) | BigCst->getValue();
Value *NewVal = ConstantInt::get(AndCst->getType()->getContext(), N);