Don't count DebugInfo instructions in another limit

(lest they affect codegen).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65915 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index e0d3ac4d4282ce918c2c0fcb626e4fd0b8563790..f3fb4fb7f481ffc82cdf3ebbcd03b2dd2cc7d00c 100644 (file)
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -11439,12 +11439,18 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) {
                                 SI.getAlignment()))
     SI.setAlignment(KnownAlign);
 
-  // Do really simple DSE, to catch cases where there are several consequtive
+  // Do really simple DSE, to catch cases where there are several consecutive
   // stores to the same location, separated by a few arithmetic operations. This
   // situation often occurs with bitfield accesses.
   BasicBlock::iterator BBI = &SI;
   for (unsigned ScanInsts = 6; BBI != SI.getParent()->begin() && ScanInsts;
        --ScanInsts) {
+    // Don't count debug info directives, lest they affect codegen.
+    if (isa<DbgInfoIntrinsic>(BBI)) {
+      ScanInsts++;
+      --BBI;
+      continue;
+    }    
     --BBI;
     
     if (StoreInst *PrevSI = dyn_cast<StoreInst>(BBI)) {