Ensure that we don't miscodegen if vlas creap into the top of the for.

This will allow us to generate break and continue even if vlas are
involved without worry that we'll silently generate bad code.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@64028 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/CGObjC.cpp b/lib/CodeGen/CGObjC.cpp
index d62cfdc3063288ab984309eb5e78e68262963a17..a116316641f547aea80eb6c0c13b24fe95348916 100644 (file)
--- a/lib/CodeGen/CGObjC.cpp
+++ b/lib/CodeGen/CGObjC.cpp
@@ -446,6 +446,10 @@ void CodeGenFunction::EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S)
   llvm::BasicBlock *LoopStart = createBasicBlock("loopstart");
   EmitBlock(LoopStart);
 
+  // We want to ensure there are no vlas between here and when we
+  // push the break and continue context below.
+  llvm::Value *saveStackDepth = StackDepth;
+
   llvm::Value *CounterPtr = CreateTempAlloca(UnsignedLongLTy, "counter.ptr");
   Builder.CreateStore(Zero, CounterPtr);
   
@@ -515,6 +519,8 @@ void CodeGenFunction::EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S)
   llvm::BasicBlock *LoopEnd = createBasicBlock("loopend");
   llvm::BasicBlock *AfterBody = createBasicBlock("afterbody");
   
+  assert (StackDepth == saveStackDepth && "vla unhandled in for");
+
   BreakContinuePush(LoopEnd, AfterBody);
 
   EmitStmt(S.getBody());