this xform is already done by the constant folder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40124 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 33fd843..792d615 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -6469,11 +6469,6 @@
Instruction *InstCombiner::commonCastTransforms(CastInst &CI) {
Value *Src = CI.getOperand(0);
- // Casting undef to anything results in undef so might as just replace it and
- // get rid of the cast.
- if (isa<UndefValue>(Src)) // cast undef -> undef
- return ReplaceInstUsesWith(CI, UndefValue::get(CI.getType()));
-
// Many cases of "cast of a cast" are eliminable. If it's eliminable we just
// eliminate it now.
if (CastInst *CSrc = dyn_cast<CastInst>(Src)) { // A->B->C cast
@@ -9888,7 +9883,7 @@
Inst->eraseFromParent();
continue;
}
-
+
IC.AddToWorkList(Inst);
}