commit d96a8e771ca9f406f0fa1dd4639997335ae444a7
author John McCall <rjmccall@apple.com> Wed Aug 11 00:16:14 2010 +0000
committer John McCall <rjmccall@apple.com> Wed Aug 11 00:16:14 2010 +0000
tree 7fbb0ec0b7727e1b43f49076e6bd647ec8b187c1
parent f598087b4adfea164acdd5b53ea2951bde740a2d

Fix a bug in @finally emission in both the fragile and non-fragile EH schemes
where we weren't accounting for the possibility that a @finally block might
have internal cleanups and therefore might write to the cleanup destination slot.

Fixes <rdar://problem/8293901>.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@110760 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CGException.cpp

diff --git a/lib/CodeGen/CGException.cpp b/lib/CodeGen/CGException.cpp
index 99105e1..746f68d 100644
--- a/lib/CodeGen/CGException.cpp
+++ b/lib/CodeGen/CGException.cpp
@@ -1326,6 +1326,12 @@
         CGF.EHStack.pushCleanup<CallEndCatchForFinally>(NormalAndEHCleanup,
                                                         ForEHVar, EndCatchFn);
 
+      // Save the current cleanup destination in case there are
+      // cleanups in the finally block.
+      llvm::Value *SavedCleanupDest =
+        CGF.Builder.CreateLoad(CGF.getNormalCleanupDestSlot(),
+                               "cleanup.dest.saved");
+
       // Emit the finally block.
       CGF.EmitStmt(Body);
 
@@ -1349,6 +1355,10 @@
         CGF.Builder.CreateUnreachable();
 
         CGF.EmitBlock(ContBB);
+
+        // Restore the cleanup destination.
+        CGF.Builder.CreateStore(SavedCleanupDest,
+                                CGF.getNormalCleanupDestSlot());
       }
 
       // Leave the end-catch cleanup.  As an optimization, pretend that

lib/CodeGen/CGObjCMac.cpp

diff --git a/lib/CodeGen/CGObjCMac.cpp b/lib/CodeGen/CGObjCMac.cpp
index 3a80330..47e303f 100644
--- a/lib/CodeGen/CGObjCMac.cpp
+++ b/lib/CodeGen/CGObjCMac.cpp
@@ -2674,11 +2674,22 @@
 
       if (isa<ObjCAtTryStmt>(S)) {
         if (const ObjCAtFinallyStmt* FinallyStmt =
-            cast<ObjCAtTryStmt>(S).getFinallyStmt())
+              cast<ObjCAtTryStmt>(S).getFinallyStmt()) {
+          // Save the current cleanup destination in case there's
+          // control flow inside the finally statement.
+          llvm::Value *CurCleanupDest =
+            CGF.Builder.CreateLoad(CGF.getNormalCleanupDestSlot());
+
           CGF.EmitStmt(FinallyStmt->getFinallyBody());
 
-        // Currently, the end of the cleanup must always exist.
-        CGF.EnsureInsertPoint();
+          if (CGF.HaveInsertPoint()) {
+            CGF.Builder.CreateStore(CurCleanupDest,
+                                    CGF.getNormalCleanupDestSlot());
+          } else {
+            // Currently, the end of the cleanup must always exist.
+            CGF.EnsureInsertPoint();
+          }
+        }
       } else {
         // Emit objc_sync_exit(expr); as finally's sole statement for
         // @synchronized.
@@ -3030,8 +3041,8 @@
   llvm::BasicBlock *TryBlock = CGF.createBasicBlock("try");
   llvm::BasicBlock *TryHandler = CGF.createBasicBlock("try.handler");
   llvm::Value *DidCatch =
-    CGF.Builder.CreateIsNull(SetJmpResult, "did_catch_exception");
-  CGF.Builder.CreateCondBr(DidCatch, TryBlock, TryHandler);
+    CGF.Builder.CreateIsNotNull(SetJmpResult, "did_catch_exception");
+  CGF.Builder.CreateCondBr(DidCatch, TryHandler, TryBlock);
 
   // Emit the protected block.
   CGF.EmitBlock(TryBlock);