diff options
Diffstat (limited to 'llvm/lib/Transforms')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp index 50b5b3740f1..90525950ea6 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp @@ -683,11 +683,27 @@ Instruction *InstCombiner::FoldSPFofSPF(Instruction *Inner, return ReplaceInstUsesWith(Outer, C); } - // TODO: MIN(MIN(A, 23), 97) + // MIN(MIN(A, 23), 97) -> MIN(A, 23) + // MAX(MAX(A, 97), 23) -> MAX(A, 97) + if (SPF1 == SPF2) { + if (ConstantInt *CB = dyn_cast<ConstantInt>(B)) { + if (ConstantInt *CC = dyn_cast<ConstantInt>(C)) { + APInt ACB = CB->getValue(); + APInt ACC = CC->getValue(); + if ((SPF1 == SPF_UMIN && ACB.ule(ACC)) || + (SPF1 == SPF_SMIN && ACB.sle(ACC)) || + (SPF1 == SPF_UMAX && ACB.uge(ACC)) || + (SPF1 == SPF_SMAX && ACB.sge(ACC))) + return ReplaceInstUsesWith(Outer, Inner); + } + } + } + + // TODO: MIN(MIN(A, 97), 23) -> MIN(A, 23) + // TODO: MAX(MAX(A, 23), 97) -> MAX(A, 97) return nullptr; } - /// foldSelectICmpAnd - If one of the constants is zero (we know they can't /// both be) and we have an icmp instruction with zero, and we have an 'and' /// with the non-constant value and a power of two we can turn the select |
