Provide InstCombines for the following 3 cases:

A * (1 - (uitofp i1 C)) -> select C, 0, A
B * (uitofp i1 C) -> select C, B, 0
select C, 0, A + select C, B, 0 -> select C, B, A

These come up in code that has been hand-optimized from a select to a linear blend, 
on platforms where that may have mattered. We want to undo such changes 
with the following transform:
A*(1 - uitofp i1 C) + B*(uitofp i1 C) -> select C, A, B



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181216 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 0 deletions

diff --git a/include/llvm/Support/PatternMatch.h b/include/llvm/Support/PatternMatch.h
index 51b66b0dcd..95d9d782ec 100644
--- a/include/llvm/Support/PatternMatch.h
+++ b/include/llvm/Support/PatternMatch.h
@@ -693,6 +693,12 @@ m_ZExt(const OpTy &Op) {
   return CastClass_match<OpTy, Instruction::ZExt>(Op);
 }
 
+/// m_UIToFP
+template<typename OpTy>
+inline CastClass_match<OpTy, Instruction::UIToFP>
+m_UIToFp(const OpTy &Op) { 
+  return CastClass_match<OpTy, Instruction::UIToFP>(Op);
+}
 
 //===----------------------------------------------------------------------===//
 // Matchers for unary operators