[InstCombine] Teach select01 helper of foldSelectIntoOp to handle vector splats

We were handling some vectors in foldSelectIntoOp, but not if the operand of the bin op was any kind of vector constant. This patch fixes it to treat vector splats the same as scalars.

Differential Revision: https://reviews.llvm.org/D37232

llvm-svn: 311940

1 files changed, 6 insertions, 7 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
index 5712fa4f09c..08aba886575 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
@@ -220,16 +220,15 @@ Instruction *InstCombiner::foldSelectOpOp(SelectInst &SI, Instruction *TI,
 }
 
 static bool isSelect01(Constant *C1, Constant *C2) {
-  ConstantInt *C1I = dyn_cast<ConstantInt>(C1);
-  if (!C1I)
+  const APInt *C1I, *C2I;
+  if (!match(C1, m_APInt(C1I)))
     return false;
-  ConstantInt *C2I = dyn_cast<ConstantInt>(C2);
-  if (!C2I)
+  if (!match(C2, m_APInt(C2I)))
     return false;
-  if (!C1I->isZero() && !C2I->isZero()) // One side must be zero.
+  if (!C1I->isNullValue() && !C2I->isNullValue()) // One side must be zero.
     return false;
-  return C1I->isOne() || C1I->isMinusOne() ||
-         C2I->isOne() || C2I->isMinusOne();
+  return C1I->isOneValue() || C1I->isAllOnesValue() ||
+         C2I->isOneValue() || C2I->isAllOnesValue();
 }
 
 /// Try to fold the select into one of the operands to allow further