Don't emit a redundant BitCastInst if the value to be defined in the
preheader is already an instruction.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74031 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index ba60058..312b957 100644
--- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -1642,7 +1642,8 @@
       // the preheader, instead of being forward substituted into the uses.  We
       // do this by forcing a BitCast (noop cast) to be inserted into the
       // preheader in this case.
-      if (!fitsInAddressMode(Base, getAccessType(Inst), TLI, false)) {
+      if (!fitsInAddressMode(Base, getAccessType(Inst), TLI, false) &&
+          !isa<Instruction>(BaseV)) {
         // We want this constant emitted into the preheader! This is just
         // using cast as a copy so BitCast (no-op cast) is appropriate
         BaseV = new BitCastInst(BaseV, BaseV->getType(), "preheaderinsert",