diff options
| -rw-r--r-- | lib/Transforms/InstCombine/InstCombineSelect.cpp | 13 | ||||
| -rw-r--r-- | test/Transforms/InstCombine/select.ll | 17 |
2 files changed, 29 insertions, 1 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineSelect.cpp b/lib/Transforms/InstCombine/InstCombineSelect.cpp index ff41ab834b..97abc769ae 100644 --- a/lib/Transforms/InstCombine/InstCombineSelect.cpp +++ b/lib/Transforms/InstCombine/InstCombineSelect.cpp @@ -792,6 +792,19 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) { if (Instruction *NV = FoldOpIntoPhi(SI)) return NV; + if (SelectInst *TrueSI = dyn_cast<SelectInst>(TrueVal)) { + if (TrueSI->getCondition() == CondVal) { + SI.setOperand(1, TrueSI->getTrueValue()); + return &SI; + } + } + if (SelectInst *FalseSI = dyn_cast<SelectInst>(FalseVal)) { + if (FalseSI->getCondition() == CondVal) { + SI.setOperand(2, FalseSI->getFalseValue()); + return &SI; + } + } + if (BinaryOperator::isNot(CondVal)) { SI.setOperand(0, BinaryOperator::getNotArgument(CondVal)); SI.setOperand(1, FalseVal); diff --git a/test/Transforms/InstCombine/select.ll b/test/Transforms/InstCombine/select.ll index 54cfc467cc..b66b22cff6 100644 --- a/test/Transforms/InstCombine/select.ll +++ b/test/Transforms/InstCombine/select.ll @@ -692,7 +692,7 @@ define i64 @test50(i32 %a) nounwind { ; PR8994 -; Theis select instruction can't be eliminated because trying to do so would +; This select instruction can't be eliminated because trying to do so would ; change the number of vector elements. This used to assert. define i48 @test51(<3 x i1> %icmp, <3 x i16> %tmp) { %select = select <3 x i1> %icmp, <3 x i16> zeroinitializer, <3 x i16> %tmp @@ -700,3 +700,18 @@ define i48 @test51(<3 x i1> %icmp, <3 x i16> %tmp) { %tmp2 = bitcast <3 x i16> %select to i48 ret i48 %tmp2 } + +; PR8575 + +@g = common global i32 0, align 4 +define void @test52(i32 %n, i32 %m) nounwind { +entry: + %cmp = icmp sgt i32 %n, %m + %. = select i1 %cmp, i32 1, i32 3 + %add = add nsw i32 %., 3 + %storemerge = select i1 %cmp, i32 %., i32 %add +; CHECK: select i1 %cmp, i32 1, i32 6 + store i32 %storemerge, i32* @g, align 4 + ret void +} + |