Revert r237539: "Reapply r237520 with another fix for infinite looping"

This caused PR23583.

llvm-svn: 237739

1 files changed, 0 insertions, 9 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
index 48ab0eb..9c2bc34 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
@@ -435,15 +435,6 @@ Instruction *InstCombiner::visitTrunc(TruncInst &CI) {
   if (Instruction *Result = commonCastTransforms(CI))
     return Result;
 
-  // Test if the trunc is the user of a select which is part of a
-  // minimum or maximum operation. If so, don't do any more simplification.
-  // Even simplifying demanded bits can break the canonical form of a 
-  // min/max.
-  Value *LHS, *RHS;
-  if (SelectInst *SI = dyn_cast<SelectInst>(CI.getOperand(0)))
-    if (matchSelectPattern(SI, LHS, RHS) != SPF_UNKNOWN)
-      return nullptr;
-  
   // See if we can simplify any instructions used by the input whose sole
   // purpose is to compute bits we don't care about.
   if (SimplifyDemandedInstructionBits(CI))