diff options
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp | 2 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstCombine/abs-1.ll | 30 |
2 files changed, 31 insertions, 1 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp index e70078a73c5..c88270fa0ea 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp @@ -818,7 +818,7 @@ static Instruction *canonicalizeAbsNabs(SelectInst &Sel, ICmpInst &Cmp, // Create the canonical compare. Cmp.setPredicate(ICmpInst::ICMP_SLT); - Cmp.setOperand(1, ConstantInt::getNullValue(LHS->getType())); + Cmp.setOperand(1, ConstantInt::getNullValue(Cmp.getOperand(0)->getType())); // If the select operands do not change, we're done. Value *TVal = Sel.getTrueValue(); diff --git a/llvm/test/Transforms/InstCombine/abs-1.ll b/llvm/test/Transforms/InstCombine/abs-1.ll index ee6b6674c0b..92a9de821aa 100644 --- a/llvm/test/Transforms/InstCombine/abs-1.ll +++ b/llvm/test/Transforms/InstCombine/abs-1.ll @@ -101,6 +101,21 @@ define i8 @abs_canonical_4(i8 %x) { ret i8 %abs } +define i32 @abs_canonical_5(i8 %x) { +; CHECK-LABEL: @abs_canonical_5( +; CHECK-NEXT: [[CMP:%.*]] = icmp slt i8 [[X:%.*]], 0 +; CHECK-NEXT: [[CONV:%.*]] = sext i8 [[X]] to i32 +; CHECK-NEXT: [[NEG:%.*]] = sub nsw i32 0, [[CONV]] +; CHECK-NEXT: [[ABS:%.*]] = select i1 [[CMP]], i32 [[NEG]], i32 [[CONV]] +; CHECK-NEXT: ret i32 [[ABS]] +; + %cmp = icmp sgt i8 %x, 0 + %conv = sext i8 %x to i32 + %neg = sub i32 0, %conv + %abs = select i1 %cmp, i32 %conv, i32 %neg + ret i32 %abs +} + ; We have a canonical form of nabs to make CSE easier. define i8 @nabs_canonical_1(i8 %x) { @@ -159,6 +174,21 @@ define i8 @nabs_canonical_4(i8 %x) { ret i8 %abs } +define i32 @nabs_canonical_5(i8 %x) { +; CHECK-LABEL: @nabs_canonical_5( +; CHECK-NEXT: [[CMP:%.*]] = icmp slt i8 [[X:%.*]], 0 +; CHECK-NEXT: [[CONV:%.*]] = sext i8 [[X]] to i32 +; CHECK-NEXT: [[NEG:%.*]] = sub nsw i32 0, [[CONV]] +; CHECK-NEXT: [[ABS:%.*]] = select i1 [[CMP]], i32 [[CONV]], i32 [[NEG]] +; CHECK-NEXT: ret i32 [[ABS]] +; + %cmp = icmp sgt i8 %x, 0 + %conv = sext i8 %x to i32 + %neg = sub i32 0, %conv + %abs = select i1 %cmp, i32 %neg, i32 %conv + ret i32 %abs +} + ; The following 5 tests use a shift+add+xor to implement abs(): ; B = ashr i8 A, 7 -- smear the sign bit. ; xor (add A, B), B -- add -1 and flip bits if negative |
