Make my earlier patch to skip debug intrinsics
when counting work; it was only off by 1.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65993 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 8f094b7..5b50ab5 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -11483,6 +11483,7 @@
   BasicBlock::iterator BBI = &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.
@@ -11490,10 +11491,8 @@
         (isa<BitCastInst>(BBI) && BBI->hasOneUse() &&
          isa<DbgDeclareInst>(BBI->use_begin()))) {
       ScanInsts++;
-      --BBI;
       continue;
     }    
-    --BBI;
     
     if (StoreInst *PrevSI = dyn_cast<StoreInst>(BBI)) {
       // Prev store isn't volatile, and stores to the same location?