From: John McCall <rjmccall@apple.com>
Date: Sat, 26 Feb 2011 09:12:15 +0000 (+0000)
Subject: Zero-initialize the struct-return slot of an Objective-C message
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=a1bcc4ddb1ed8be9be6950232941d80a04f80819;p=clang

Zero-initialize the struct-return slot of an Objective-C message
send before making the call.  Fixes rdar://problem/7854674



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@126543 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGObjCMac.cpp b/lib/CodeGen/CGObjCMac.cpp
index 7c679b9059..f5befceb0f 100644
--- a/lib/CodeGen/CGObjCMac.cpp
+++ b/lib/CodeGen/CGObjCMac.cpp
@@ -1639,6 +1639,7 @@ CGObjCCommonMac::EmitLegacyMessageSend(CodeGen::CodeGenFunction &CGF,
 
   llvm::Constant *Fn = NULL;
   if (CGM.ReturnTypeUsesSRet(FnInfo)) {
+    CGF.EmitNullInitialization(Return.getValue(), ResultType);
     Fn = (ObjCABI == 2) ?  ObjCTypes.getSendStretFn2(IsSuper)
       : ObjCTypes.getSendStretFn(IsSuper);
   } else if (CGM.ReturnTypeUsesFPRet(ResultType)) {
@@ -5629,6 +5630,7 @@ CodeGen::RValue CGObjCNonFragileABIMac::EmitMessageSend(
   llvm::Constant *Fn = 0;
   std::string Name("\01l_");
   if (CGM.ReturnTypeUsesSRet(FnInfo)) {
+    CGF.EmitNullInitialization(Return.getValue(), ResultType);
     if (IsSuper) {
       Fn = ObjCTypes.getMessageSendSuper2StretFixupFn();
       Name += "objc_msgSendSuper2_stret_fixup";
diff --git a/test/CodeGenObjC/messages-2.m b/test/CodeGenObjC/messages-2.m
index 05e30ab131..5ef2261b19 100644
--- a/test/CodeGenObjC/messages-2.m
+++ b/test/CodeGenObjC/messages-2.m
@@ -1,4 +1,7 @@
-// RUN: %clang_cc1 -emit-llvm -o %t %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -emit-llvm -o - %s | FileCheck %s -check-prefix=CHECK
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -fobjc-nonfragile-abi -emit-llvm -o - %s | FileCheck %s -check-prefix=CHECK-NF
+
+// Most of this test is apparently just verifying that we don't crash.
 
 int printf(const char *, ...);
 
@@ -140,3 +143,21 @@ typedef struct {
   return 5;
 }
 @end
+
+// rdar://problem/7854674
+// CHECK:    define void @test0([[A:%.*]]*
+// CHECK-NF: define void @test0([[A:%.*]]*
+void test0(A *a) {
+  // CHECK:         alloca [[A]]*
+  // CHECK-NEXT:    [[POINT:%.*]] = alloca [[POINT_T:%.*]],
+  // CHECK-NF:      alloca [[A]]*
+  // CHECK-NF-NEXT: [[POINT:%.*]] = alloca [[POINT_T:%.*]],
+
+  // CHECK:         [[T0:%.*]] = bitcast [[POINT_T]]* [[POINT]] to i8*
+  // CHECK-NEXT:    call void @llvm.memset.p0i8.i64(i8* [[T0]], i8 0, i64 48, i32 4, i1 false)
+  // CHECK-NEXT:    call {{.*}} @objc_msgSend_stret to
+  // CHECK-NF:      [[T0:%.*]] = bitcast [[POINT_T]]* [[POINT]] to i8*
+  // CHECK-NF-NEXT: call void @llvm.memset.p0i8.i64(i8* [[T0]], i8 0, i64 48, i32 4, i1 false)
+  // CHECK-NF-NEXT: call {{.*}} @objc_msgSend_stret to
+  MyPoint point = [a returnAPoint];
+}
diff --git a/test/CodeGenObjC/messages.m b/test/CodeGenObjC/messages.m
index 5f77a8e327..b36fe5b644 100644
--- a/test/CodeGenObjC/messages.m
+++ b/test/CodeGenObjC/messages.m
@@ -1,9 +1,7 @@
-// RUN: %clang_cc1 -emit-llvm -o %t %s
-// RUN: grep "objc_msgSend" %t | count 6
-// RUN: %clang_cc1 -fgnu-runtime -emit-llvm -o %t %s
-// RUN: grep "objc_msg_lookup" %t | count 6
-// RUN: %clang_cc1 -fgnu-runtime -fobjc-nonfragile-abi -emit-llvm -o %t %s
-// RUN: grep "objc_msg_lookup_sender" %t | count 6
+// RUN: %clang_cc1 -emit-llvm -o - %s | FileCheck %s -check-prefix=CHECK-MAC
+// RUN: %clang_cc1 -emit-llvm -fobjc-nonfragile-abi -o - %s | FileCheck %s -check-prefix=CHECK-MAC-NF
+// RUN: %clang_cc1 -fgnu-runtime -emit-llvm -o - %s | FileCheck %s -check-prefix=CHECK-GNU
+// RUN: %clang_cc1 -fgnu-runtime -fobjc-nonfragile-abi -emit-llvm -o - %s | FileCheck %s -check-prefix CHECK-GNU-NF
 
 typedef struct {
   int x;
@@ -15,12 +13,35 @@ void f0(id a) {
   int i;
   MyPoint pt = { 1, 2};
 
+  // CHECK-MAC: call {{.*}} @objc_msgSend(
+  // CHECK-MAC-NF: call {{.*}} @objc_msgSend(
+  // CHECK-GNU: call {{.*}} @objc_msg_lookup(
+  // CHECK-GNU-NF: call {{.*}} @objc_msg_lookup_sender(
   [a print0];
+
+  // CHECK-MAC: call {{.*}} @objc_msgSend to
+  // CHECK-MAC-NF: call {{.*}} @objc_msgSend to
+  // CHECK-GNU: call {{.*}} @objc_msg_lookup to
+  // CHECK-GNU-NF: call {{.*}} @objc_msg_lookup_sender to
   [a print1: 10];
+
+  // CHECK-MAC: call {{.*}} @objc_msgSend to
+  // CHECK-MAC-NF: call {{.*}} @objc_msgSend to
+  // CHECK-GNU: call {{.*}} @objc_msg_lookup to
+  // CHECK-GNU-NF: call {{.*}} @objc_msg_lookup_sender to
   [a print2: 10 and: "hello" and: 2.2];
+
+  // CHECK-MAC: call {{.*}} @objc_msgSend to
+  // CHECK-MAC-NF: call {{.*}} @objc_msgSend to
+  // CHECK-GNU: call {{.*}} @objc_msg_lookup to
+  // CHECK-GNU-NF: call {{.*}} @objc_msg_lookup_sender to
   [a takeStruct: pt ];
   
   void *s = @selector(print0);
   for (i=0; i<2; ++i)
+    // CHECK-MAC: call {{.*}} @objc_msgSend to
+    // CHECK-MAC-NF: call {{.*}} @objc_msgSend to
+    // CHECK-GNU: call {{.*}} @objc_msg_lookup to
+    // CHECK-GNU-NF: call {{.*}} @objc_msg_lookup_sender to
     [a performSelector:s];
 }