CodeGen: avoid use of @clang.arc.use intrinsic at O0

The clang.arc.use intrinsic is removed via the ARC Contract Pass.  This
pass is only executed in optimized builds (>= opt level 1).  Prevent the
optimization implemented in SVN r301667 from triggering at optimization
level 0 like every other ARC use intrinsic usage.

llvm-svn: 302270

1 files changed, 6 insertions, 2 deletions

diff --git a/clang/lib/CodeGen/CGBlocks.cpp b/clang/lib/CodeGen/CGBlocks.cpp
index 791a57e61f5..2b2a92dd601 100644
--- a/clang/lib/CodeGen/CGBlocks.cpp
+++ b/clang/lib/CodeGen/CGBlocks.cpp
@@ -623,9 +623,13 @@ static void enterBlockScope(CodeGenFunction &CGF, BlockDecl *block) {
     // For const-qualified captures, emit clang.arc.use to ensure the captured
     // object doesn't get released while we are still depending on its validity
     // within the block.
-    if (VT.isConstQualified() && VT.getObjCLifetime() == Qualifiers::OCL_Strong)
+    if (VT.isConstQualified() &&
+        VT.getObjCLifetime() == Qualifiers::OCL_Strong &&
+        CGF.CGM.getCodeGenOpts().OptimizationLevel != 0) {
+      assert(CGF.CGM.getLangOpts().ObjCAutoRefCount &&
+             "expected ObjC ARC to be enabled");
       destroyer = CodeGenFunction::emitARCIntrinsicUse;
-    else if (dtorKind == QualType::DK_objc_strong_lifetime) {
+    } else if (dtorKind == QualType::DK_objc_strong_lifetime) {
       destroyer = CodeGenFunction::destroyARCStrongImprecise;
     } else {
       destroyer = CGF.getDestroyer(dtorKind);