Always skip ptr-to-ptr bitcasts when counting,

per Chris' suggestion.  Slightly faster.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65999 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 5 deletions

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 5b50ab56a3..66ac48181e 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -11484,12 +11484,12 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) {
   for (unsigned ScanInsts = 6; BBI != SI.getParent()->begin() && ScanInsts;
        --ScanInsts) {
     --BBI;
-    // Don't count debug info directives, lest they affect codegen.
-    // Likewise, we skip bitcasts that feed into a llvm.dbg.declare; these are
-    // not present when debugging is off.
+    // Don't count debug info directives, lest they affect codegen,
+    // and we skip pointer-to-pointer bitcasts, which are NOPs.
+    // It is necessary for correctness to skip those that feed into a
+    // llvm.dbg.declare, as these are not present when debugging is off.
     if (isa<DbgInfoIntrinsic>(BBI) ||
-        (isa<BitCastInst>(BBI) && BBI->hasOneUse() &&
-         isa<DbgDeclareInst>(BBI->use_begin()))) {
+        (isa<BitCastInst>(BBI) && isa<PointerType>(BBI->getType()))) {
       ScanInsts++;
       continue;
     }