diff options
| -rw-r--r-- | lib/CodeGen/CGStmt.cpp | 12 | ||||
| -rw-r--r-- | lib/Sema/JumpDiagnostics.cpp | 11 | ||||
| -rw-r--r-- | test/CodeGenCXX/exceptions.cpp | 1 | ||||
| -rw-r--r-- | test/CodeGenObjC/arc-blocks.m | 57 |
4 files changed, 78 insertions, 3 deletions
diff --git a/lib/CodeGen/CGStmt.cpp b/lib/CodeGen/CGStmt.cpp index 4fdbfd0390..77414bf8a4 100644 --- a/lib/CodeGen/CGStmt.cpp +++ b/lib/CodeGen/CGStmt.cpp @@ -743,6 +743,17 @@ void CodeGenFunction::EmitReturnStmt(const ReturnStmt &S) { // Emit the result value, even if unused, to evalute the side effects. const Expr *RV = S.getRetValue(); + // Treat block literals in a return expression as if they appeared + // in their own scope. This permits a small, easily-implemented + // exception to our over-conservative rules about not jumping to + // statements following block literals with non-trivial cleanups. + RunCleanupsScope cleanupScope(*this); + if (const ExprWithCleanups *cleanups = + dyn_cast_or_null<ExprWithCleanups>(RV)) { + enterFullExpression(cleanups); + RV = cleanups->getSubExpr(); + } + // FIXME: Clean this up by using an LValue for ReturnTemp, // EmitStoreThroughLValue, and EmitAnyExpr. if (S.getNRVOCandidate() && S.getNRVOCandidate()->isNRVOVariable() && @@ -779,6 +790,7 @@ void CodeGenFunction::EmitReturnStmt(const ReturnStmt &S) { AggValueSlot::IsNotAliased)); } + cleanupScope.ForceCleanup(); EmitBranchThroughCleanup(ReturnBlock); } diff --git a/lib/Sema/JumpDiagnostics.cpp b/lib/Sema/JumpDiagnostics.cpp index ab786c65aa..a48779a1c3 100644 --- a/lib/Sema/JumpDiagnostics.cpp +++ b/lib/Sema/JumpDiagnostics.cpp @@ -453,14 +453,19 @@ void JumpScopeChecker::BuildScopeInformation(Stmt *S, unsigned &origParentScope) BuildScopeInformation(AS->getSubStmt(), (newParentScope = Scopes.size()-1)); continue; } - - if (const BlockExpr *BE = dyn_cast<BlockExpr>(SubStmt)) { - const BlockDecl *BDecl = BE->getBlockDecl(); + + // Disallow jumps past full-expressions that use blocks with + // non-trivial cleanups of their captures. This is theoretically + // implementable but a lot of work which we haven't felt up to doing. + if (ExprWithCleanups *EWC = dyn_cast<ExprWithCleanups>(SubStmt)) { + for (unsigned i = 0, e = EWC->getNumObjects(); i != e; ++i) { + const BlockDecl *BDecl = EWC->getObject(i); for (BlockDecl::capture_const_iterator ci = BDecl->capture_begin(), ce = BDecl->capture_end(); ci != ce; ++ci) { VarDecl *variable = ci->getVariable(); BuildScopeInformation(variable, BDecl, ParentScope); } + } } // Recursively walk the AST. diff --git a/test/CodeGenCXX/exceptions.cpp b/test/CodeGenCXX/exceptions.cpp index 8c20c9e9ce..723e8d1393 100644 --- a/test/CodeGenCXX/exceptions.cpp +++ b/test/CodeGenCXX/exceptions.cpp @@ -365,6 +365,7 @@ namespace test7 { // CHECK-NEXT: invoke void @_ZN5test71BC1ERKNS_1AEPS0_( // CHECK: store i1 false, i1* [[OUTER_NEW]] // CHECK: phi + // CHECK-NEXT: store [[B]]* // Destroy the inner A object. // CHECK-NEXT: load i1* [[INNER_A]] diff --git a/test/CodeGenObjC/arc-blocks.m b/test/CodeGenObjC/arc-blocks.m index 2326bce2be..cbdb49418b 100644 --- a/test/CodeGenObjC/arc-blocks.m +++ b/test/CodeGenObjC/arc-blocks.m @@ -532,3 +532,60 @@ void test16() { // CHECK-NEXT: [[SLOTREL:%.*]] = getelementptr inbounds [[BLOCK_T]]* [[BLOCK]], i32 0, i32 5 // CHECK-NEXT: store void ()* null, void ()** [[BLKVAR]], align 8 } + +// rdar://12151005 +// +// This is an intentional exception to our conservative jump-scope +// checking for full-expressions containing block literals with +// non-trivial cleanups: if the block literal appears in the operand +// of a return statement, there's no need to extend its lifetime. +id (^test17(id self, int which))(void) { + switch (which) { + case 1: return ^{ return self; }; + case 0: return ^{ return self; }; + } + return (void*) 0; +} +// CHECK: define i8* ()* @test17( +// CHECK: [[RET:%.*]] = alloca i8* ()*, align +// CHECK-NEXT: [[SELF:%.*]] = alloca i8*, +// CHECK: [[B0:%.*]] = alloca [[BLOCK:<.*>]], align +// CHECK: [[B1:%.*]] = alloca [[BLOCK]], align +// CHECK: [[T0:%.*]] = call i8* @objc_retain(i8* +// CHECK-NEXT: store i8* [[T0]], i8** [[SELF]], align +// CHECK-NOT: objc_retain +// CHECK-NOT: objc_release +// CHECK: [[DESTROY:%.*]] = getelementptr inbounds [[BLOCK]]* [[B0]], i32 0, i32 5 +// CHECK-NOT: objc_retain +// CHECK-NOT: objc_release +// CHECK: [[T0:%.*]] = getelementptr inbounds [[BLOCK]]* [[B0]], i32 0, i32 5 +// CHECK-NEXT: [[T1:%.*]] = load i8** [[SELF]], align +// CHECK-NEXT: [[T2:%.*]] = call i8* @objc_retain(i8* [[T1]]) +// CHECK-NEXT: store i8* [[T2]], i8** [[T0]], +// CHECK-NEXT: [[T0:%.*]] = bitcast [[BLOCK]]* [[B0]] to i8* ()* +// CHECK-NEXT: [[T1:%.*]] = bitcast i8* ()* [[T0]] to i8* +// CHECK-NEXT: [[T2:%.*]] = call i8* @objc_retainBlock(i8* [[T1]]) +// CHECK-NEXT: [[T3:%.*]] = bitcast i8* [[T2]] to i8* ()* +// CHECK-NEXT: store i8* ()* [[T3]], i8* ()** [[RET]] +// CHECK-NEXT: [[T0:%.*]] = load i8** [[DESTROY]] +// CHECK-NEXT: call void @objc_release(i8* [[T0]]) +// CHECK-NEXT: store i32 +// CHECK-NEXT: br label +// CHECK-NOT: objc_retain +// CHECK-NOT: objc_release +// CHECK: [[DESTROY:%.*]] = getelementptr inbounds [[BLOCK]]* [[B1]], i32 0, i32 5 +// CHECK-NOT: objc_retain +// CHECK-NOT: objc_release +// CHECK: [[T0:%.*]] = getelementptr inbounds [[BLOCK]]* [[B1]], i32 0, i32 5 +// CHECK-NEXT: [[T1:%.*]] = load i8** [[SELF]], align +// CHECK-NEXT: [[T2:%.*]] = call i8* @objc_retain(i8* [[T1]]) +// CHECK-NEXT: store i8* [[T2]], i8** [[T0]], +// CHECK-NEXT: [[T0:%.*]] = bitcast [[BLOCK]]* [[B1]] to i8* ()* +// CHECK-NEXT: [[T1:%.*]] = bitcast i8* ()* [[T0]] to i8* +// CHECK-NEXT: [[T2:%.*]] = call i8* @objc_retainBlock(i8* [[T1]]) +// CHECK-NEXT: [[T3:%.*]] = bitcast i8* [[T2]] to i8* ()* +// CHECK-NEXT: store i8* ()* [[T3]], i8* ()** [[RET]] +// CHECK-NEXT: [[T0:%.*]] = load i8** [[DESTROY]] +// CHECK-NEXT: call void @objc_release(i8* [[T0]]) +// CHECK-NEXT: store i32 +// CHECK-NEXT: br label |