Fix a subtle bug with cleanups: when activating

a previously-inactive cleanup, not only do we need a
flag variable, but we should also force the cleanup to
query the flag variable.  However, we only need to do
this when we're activating in a context that's
conditionally executed;  otherwise, we may safely
assume that the cleanup is dominated by the activation
point.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@144271 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 121 insertions, 22 deletions

diff --git a/lib/CodeGen/CGCleanup.cpp b/lib/CodeGen/CGCleanup.cpp
index b2d0786cb6..9e079c65d2 100644
--- a/lib/CodeGen/CGCleanup.cpp
+++ b/lib/CodeGen/CGCleanup.cpp
@@ -1003,27 +1003,32 @@ static void SetupCleanupBlockActivation(CodeGenFunction &CGF,
                                         ForActivation_t Kind) {
   EHCleanupScope &Scope = cast<EHCleanupScope>(*CGF.EHStack.find(C));
 
-  // We always need the flag if we're activating the cleanup, because
-  // we have to assume that the current location doesn't necessarily
-  // dominate all future uses of the cleanup.
-  bool NeedFlag = (Kind == ForActivation);
+  // We always need the flag if we're activating the cleanup in a
+  // conditional context, because we have to assume that the current
+  // location doesn't necessarily dominate the cleanup's code.
+  bool isActivatedInConditional =
+    (Kind == ForActivation && CGF.isInConditionalBranch());
+
+  bool needFlag = false;
 
   // Calculate whether the cleanup was used:
 
   //   - as a normal cleanup
-  if (Scope.isNormalCleanup() && IsUsedAsNormalCleanup(CGF.EHStack, C)) {
+  if (Scope.isNormalCleanup() &&
+      (isActivatedInConditional || IsUsedAsNormalCleanup(CGF.EHStack, C))) {
     Scope.setTestFlagInNormalCleanup();
-    NeedFlag = true;
+    needFlag = true;
   }
 
   //  - as an EH cleanup
-  if (Scope.isEHCleanup() && IsUsedAsEHCleanup(CGF.EHStack, C)) {
+  if (Scope.isEHCleanup() &&
+      (isActivatedInConditional || IsUsedAsEHCleanup(CGF.EHStack, C))) {
     Scope.setTestFlagInEHCleanup();
-    NeedFlag = true;
+    needFlag = true;
   }
 
   // If it hasn't yet been used as either, we're done.
-  if (!NeedFlag) return;
+  if (!needFlag) return;
 
   llvm::AllocaInst *Var = Scope.getActiveFlag();
   if (!Var) {
diff --git a/test/CodeGenCXX/blocks.cpp b/test/CodeGenCXX/blocks.cpp
index cc56525e1d..e3160a0394 100644
--- a/test/CodeGenCXX/blocks.cpp
+++ b/test/CodeGenCXX/blocks.cpp
@@ -128,3 +128,53 @@ namespace test4 {
   // CHECK-NEXT: ret void
 }
 
+namespace test5 {
+  struct A {
+    unsigned afield;
+    A();
+    A(const A&);
+    ~A();
+    void foo() const;
+  };
+
+  void doWithBlock(void(^)());
+
+  void test(bool cond) {
+    A x;
+    void (^b)() = (cond ? ^{ x.foo(); } : (void(^)()) 0);
+    doWithBlock(b);
+  }
+
+  // CHECK:    define void @_ZN5test54testEb(
+  // CHECK:      [[COND:%.*]] = alloca i8
+  // CHECK-NEXT: [[X:%.*]] = alloca [[A:%.*]], align 4
+  // CHECK-NEXT: [[B:%.*]] = alloca void ()*, align 8
+  // CHECK-NEXT: [[BLOCK:%.*]] = alloca [[BLOCK_T:.*]], align 8
+  // CHECK-NEXT: [[CLEANUP_ACTIVE:%.*]] = alloca i1
+  // CHECK-NEXT: store i1 false, i1* [[CLEANUP_ACTIVE]]
+  // CHECK-NEXT: [[T0:%.*]] = zext i1
+  // CHECK-NEXT: store i8 [[T0]], i8* [[COND]], align 1
+  // CHECK-NEXT: call void @_ZN5test51AC1Ev([[A]]* [[X]])
+  // CHECK-NEXT: [[CLEANUP_ADDR:%.*]] = getelementptr inbounds [[BLOCK_T]]* [[BLOCK]], i32 0, i32 5
+  // CHECK-NEXT: [[T0:%.*]] = load i8* [[COND]], align 1
+  // CHECK-NEXT: [[T1:%.*]] = trunc i8 [[T0]] to i1
+  // CHECK-NEXT: br i1 [[T1]],
+
+  // CHECK-NOT:  br
+  // CHECK:      [[CAPTURE:%.*]] = getelementptr inbounds [[BLOCK_T]]* [[BLOCK]], i32 0, i32 5
+  // CHECK-NEXT: call void @_ZN5test51AC1ERKS0_([[A]]* [[CAPTURE]], [[A]]* [[X]])
+  // CHECK-NEXT: store i1 true, i1* [[CLEANUP_ACTIVE]]
+  // CHECK-NEXT: bitcast [[BLOCK_T]]* [[BLOCK]] to void ()*
+  // CHECK-NEXT: br label
+  // CHECK:      br label
+  // CHECK:      phi
+  // CHECK-NEXT: store
+  // CHECK-NEXT: load
+  // CHECK-NEXT: call void @_ZN5test511doWithBlockEU13block_pointerFvvE(
+  // CHECK-NEXT: [[T0:%.*]] = load i1* [[CLEANUP_ACTIVE]]
+  // CHECK-NEXT: br i1 [[T0]]
+  // CHECK:      call void @_ZN5test51AD1Ev([[A]]* [[CLEANUP_ADDR]])
+  // CHECK-NEXT: br label
+  // CHECK:      call void @_ZN5test51AD1Ev([[A]]* [[X]])
+  // CHECK-NEXT: ret void
+}
diff --git a/test/CodeGenObjC/arc-blocks.m b/test/CodeGenObjC/arc-blocks.m
index 6ca5c3c352..c14380cced 100644
--- a/test/CodeGenObjC/arc-blocks.m
+++ b/test/CodeGenObjC/arc-blocks.m
@@ -25,8 +25,6 @@ void test2(id x) {
 // CHECK:    define void @test2(
 // CHECK:      [[X:%.*]] = alloca i8*,
 // CHECK-NEXT: [[BLOCK:%.*]] = alloca [[BLOCK_T:<{.*}>]],
-// CHECK-NEXT: alloca i1
-// CHECK-NEXT: store i1 false
 // CHECK-NEXT: [[PARM:%.*]] = call i8* @objc_retain(i8* {{%.*}})
 // CHECK-NEXT: store i8* [[PARM]], i8** [[X]]
 // CHECK-NEXT: [[SLOTREL:%.*]] = getelementptr inbounds [[BLOCK_T]]* [[BLOCK]], i32 0, i32 5
@@ -34,7 +32,6 @@ void test2(id x) {
 // CHECK-NEXT: [[T0:%.*]] = load i8** [[X]],
 // CHECK-NEXT: [[T1:%.*]] = call i8* @objc_retain(i8* [[T0]])
 // CHECK-NEXT: store i8* [[T1]], i8** [[SLOT]],
-// CHECK-NEXT: store i1 true
 // CHECK-NEXT: bitcast
 // CHECK-NEXT: call void @test2_helper(
 // CHECK-NEXT: [[T0:%.*]] = load i8** [[SLOTREL]]
@@ -238,7 +235,7 @@ void test7(void) {
   // CHECK-NEXT: call i8* @objc_initWeak(i8** [[SLOT]], i8* [[T0]])
   // CHECK:      call void @test7_helper(
   // CHECK-NEXT: call void @objc_destroyWeak(i8** {{%.*}})
-  // CHECK:      call void @objc_destroyWeak(i8** [[VAR]])
+  // CHECK-NEXT: call void @objc_destroyWeak(i8** [[VAR]])
   // CHECK-NEXT: ret void
 
   // CHECK:    define internal void @__test7_block_invoke_
@@ -273,7 +270,6 @@ void test7(void) {
 // CHECK-NEXT: [[T3:%.*]] = call i8* @objc_retain(i8* [[T2]])
 // CHECK-NEXT: [[T4:%.*]] = bitcast i8* [[T3]] to [[TEST8]]*
 // CHECK-NEXT: store [[TEST8]]* [[T4]], [[TEST8]]** [[T0]]
-// CHECK-NEXT: store i1 true,
 // CHECK-NEXT: bitcast [[BLOCK_T]]* [[BLOCK]] to
 // CHECK: call void @test8_helper(
 // CHECK-NEXT: [[T1:%.*]] = load [[TEST8]]** [[D0]]
@@ -288,7 +284,7 @@ void test7(void) {
 
 id test9(void) {
   typedef id __attribute__((ns_returns_retained)) blocktype(void);
-  extern test9_consume_block(blocktype^);
+  extern void test9_consume_block(blocktype^);
   return ^blocktype {
       extern id test9_produce(void);
       return test9_produce();
@@ -461,3 +457,56 @@ void test11b(void) {
 // CHECK:    define internal void @"\01-[Test12 setNblock:]"(
 // CHECK:    call void @objc_setProperty(i8* {{%.*}}, i8* {{%.*}}, i64 {{%.*}}, i8* {{%.*}}, i1 zeroext false, i1 zeroext true)
 @end
+
+// rdar://problem/10131784
+void test13(id x) {
+  extern void test13_helper(id);
+  extern void test13_use(void(^)(void));
+
+  void (^b)(void) = (x ? ^{test13_helper(x);} : 0);
+  test13_use(b);
+
+  // CHECK:    define void @test13(
+  // CHECK:      [[X:%.*]] = alloca i8*, align 8
+  // CHECK-NEXT: [[B:%.*]] = alloca void ()*, align 8
+  // CHECK-NEXT: [[BLOCK:%.*]] = alloca [[BLOCK_T:.*]], align 8
+  // CHECK-NEXT: [[CLEANUP_ACTIVE:%.*]] = alloca i1
+  // CHECK-NEXT: store i1 false, i1* [[CLEANUP_ACTIVE]]
+  // CHECK-NEXT: [[T0:%.*]] = call i8* @objc_retain(i8* {{%.*}})
+  // CHECK-NEXT: store i8* [[T0]], i8** [[X]], align 8
+  // CHECK-NEXT: [[CLEANUP_ADDR:%.*]] = getelementptr inbounds [[BLOCK_T]]* [[BLOCK]], i32 0, i32 5
+  // CHECK-NEXT: [[T0:%.*]] = load i8** [[X]], align 8
+  // CHECK-NEXT: [[T1:%.*]] = icmp ne i8* [[T0]], null
+  // CHECK-NEXT: br i1 [[T1]],
+
+  // CHECK-NOT:  br
+  // CHECK:      [[CAPTURE:%.*]] = getelementptr inbounds [[BLOCK_T]]* [[BLOCK]], i32 0, i32 5
+  // CHECK-NEXT: [[T0:%.*]] = load i8** [[X]], align 8
+  // CHECK-NEXT: [[T1:%.*]] = call i8* @objc_retain(i8* [[T0]])
+  // CHECK-NEXT: store i8* [[T1]], i8** [[CAPTURE]], align 8
+  // CHECK-NEXT: store i1 true, i1* [[CLEANUP_ACTIVE]]
+  // CHECK-NEXT: bitcast [[BLOCK_T]]* [[BLOCK]] to void ()*
+  // CHECK-NEXT: br label
+  // CHECK:      br label
+  // CHECK:      [[T0:%.*]] = phi void ()*
+  // CHECK-NEXT: [[T1:%.*]] = bitcast void ()* [[T0]] to i8*
+  // CHECK-NEXT: [[T2:%.*]] = call i8* @objc_retainBlock(i8* [[T1]])
+  // CHECK-NEXT: [[T3:%.*]] = bitcast i8* [[T2]] to void ()*
+  // CHECK-NEXT: store void ()* [[T3]], void ()** [[B]], align 8
+  // CHECK-NEXT: [[T0:%.*]] = load void ()** [[B]], align 8
+  // CHECK-NEXT: call void @test13_use(void ()* [[T0]])
+  // CHECK-NEXT: [[T0:%.*]] = load void ()** [[B]]
+  // CHECK-NEXT: [[T1:%.*]] = bitcast void ()* [[T0]] to i8*
+  // CHECK-NEXT: call void @objc_release(i8* [[T1]])
+
+  // CHECK-NEXT: [[T0:%.*]] = load i1* [[CLEANUP_ACTIVE]]
+  // CHECK-NEXT: br i1 [[T0]]
+  // CHECK:      [[T0:%.*]] = load i8** [[CLEANUP_ADDR]]
+  // CHECK-NEXT: call void @objc_release(i8* [[T0]])
+  // CHECK-NEXT: br label
+
+  // CHECK:      [[T0:%.*]] = load i8** [[X]]
+  // CHECK-NEXT: call void @objc_release(i8* [[T0]])
+  // CHECK-NEXT: ret void
+}
+
diff --git a/test/CodeGenObjC/arc-foreach.m b/test/CodeGenObjC/arc-foreach.m
index de550328f0..67fad4d9b0 100644
--- a/test/CodeGenObjC/arc-foreach.m
+++ b/test/CodeGenObjC/arc-foreach.m
@@ -29,9 +29,6 @@ void test0(NSArray *array) {
 // CHECK-LP64-NEXT: [[BUFFER:%.*]] = alloca [16 x i8*], align 8
 // CHECK-LP64-NEXT: [[BLOCK:%.*]] = alloca [[BLOCK_T:<{.*}>]],
 
-// CHECK-LP64-NEXT: [[CAP_ACTIVE:%.*]] = alloca i1
-// CHECK-LP64-NEXT: store i1 false, i1* [[CAP_ACTIVE]]
-
 // Initialize 'array'.
 // CHECK-LP64-NEXT: [[T0:%.*]] = bitcast [[ARRAY_T:%.*]]* {{%.*}} to i8*
 // CHECK-LP64-NEXT: [[T1:%.*]] = call i8* @objc_retain(i8* [[T0]])
@@ -68,7 +65,6 @@ void test0(NSArray *array) {
 // CHECK-LP64-NEXT: [[T1:%.*]] = load i8** [[X]]
 // CHECK-LP64-NEXT: [[T2:%.*]] = call i8* @objc_retain(i8* [[T1]])
 // CHECK-LP64-NEXT: store i8* [[T2]], i8** [[T0]]
-// CHECK-LP64-NEXT: store i1 true, i1* [[CAP_ACTIVE]]
 // CHECK-LP64-NEXT: [[T1:%.*]] = bitcast [[BLOCK_T]]* [[BLOCK]] 
 // CHECK-LP64: call void @use_block(
 // CHECK-LP64-NEXT: [[T1:%.*]] = load i8** [[D0]]
@@ -117,11 +113,10 @@ void test1(NSArray *array) {
 // CHECK-LP64:      [[T0:%.*]] = getelementptr inbounds [[BLOCK_T]]* [[BLOCK]], i32 0, i32 5
 // CHECK-LP64-NEXT: [[T1:%.*]] = call i8* @objc_loadWeak(i8** [[X]])
 // CHECK-LP64-NEXT: call i8* @objc_initWeak(i8** [[T0]], i8* [[T1]])
-// CHECK-LP64-NEXT: store i1 true,
 // CHECK-LP64-NEXT: [[T1:%.*]] = bitcast [[BLOCK_T]]* [[BLOCK]] to
 // CHECK-LP64: call void @use_block
-// CHECK-LP64:      call void @objc_destroyWeak(i8** [[D0]])
-// CHECK-LP64:      call void @objc_destroyWeak(i8** [[X]])
+// CHECK-LP64-NEXT: call void @objc_destroyWeak(i8** [[D0]])
+// CHECK-LP64-NEXT: call void @objc_destroyWeak(i8** [[X]])
 
 // rdar://problem/9817306
 @interface Test2