Do not move variable sized allocations to the top of the caller, which might

break dominance relationships, and is otherwise bad.  This fixes bug:
Inline/2003-10-13-AllocaDominanceProblem.ll.  This also fixes miscompilation
of 3 176.gcc source files (reload1.c, global.c, flow.c)

llvm-svn: 9109

1 files changed, 5 insertions, 7 deletions

diff --git a/llvm/lib/Transforms/Utils/InlineFunction.cpp b/llvm/lib/Transforms/Utils/InlineFunction.cpp
index 01ffb253e4b..592babc1f93 100644
--- a/llvm/lib/Transforms/Utils/InlineFunction.cpp
+++ b/llvm/lib/Transforms/Utils/InlineFunction.cpp
@@ -175,13 +175,11 @@ bool InlineFunction(CallSite CS) {
     
     for (BasicBlock::iterator I = LastBlock->begin(), E = LastBlock->end();
          I != E; )
-      if (AllocaInst *AI = dyn_cast<AllocaInst>(I)) {
-        ++I;  // Move to the next instruction
-        LastBlock->getInstList().remove(AI);
-        Caller->front().getInstList().insert(InsertPoint, AI);      
-      } else {
-        ++I;
-      }
+      if (AllocaInst *AI = dyn_cast<AllocaInst>(I++))
+        if (isa<Constant>(AI->getArraySize())) {
+          LastBlock->getInstList().remove(AI);
+          Caller->front().getInstList().insert(InsertPoint, AI);      
+        }
   }
 
   // If we just inlined a call due to an invoke instruction, scan the inlined