ms_struct layout replaces platform-specific behavior like

useBitFieldTypeAlignment() and appears to ignore the special
bit-packing semantics of __attribute__((packed)).

Further flesh out an already-extensive comment.

llvm-svn: 201282

1 files changed, 43 insertions, 0 deletions

diff --git a/clang/test/CodeGen/ms_struct-bitfield.c b/clang/test/CodeGen/ms_struct-bitfield.c
index 451113c123e..08f2a5b60a5 100644
--- a/clang/test/CodeGen/ms_struct-bitfield.c
+++ b/clang/test/CodeGen/ms_struct-bitfield.c
@@ -1,7 +1,11 @@
 // RUN: %clang_cc1 -emit-llvm -o - -triple x86_64-apple-darwin9 %s | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm -o - -triple thumbv7-apple-ios -target-abi apcs-gnu %s | FileCheck %s -check-prefix=CHECK-ARM
 
 // rdar://8823265
 
+// Note that we're declaring global variables with these types,
+// triggering both Sema and IRGen struct layout.
+
 #define ATTR __attribute__((__ms_struct__))
 
 struct
@@ -12,6 +16,7 @@ struct
 } ATTR t1;
 int s1 = sizeof(t1);
 // CHECK: @s1 = global i32 2
+// CHECK-ARM: @s1 = global i32 2
 
 struct
 {
@@ -23,6 +28,7 @@ struct
 } ATTR t2;
 int s2 = sizeof(t2);
 // CHECK: @s2 = global i32 2
+// CHECK-ARM: @s2 = global i32 2
 
 struct
 {
@@ -36,6 +42,7 @@ struct
 } ATTR t3;
 int s3 = sizeof(t3);
 // CHECK: @s3 = global i32 2
+// CHECK-ARM: @s3 = global i32 2
 
 struct
 {
@@ -44,6 +51,7 @@ struct
 } ATTR t4;
 int s4 = sizeof(t4);
 // CHECK: @s4 = global i32 1
+// CHECK-ARM: @s4 = global i32 1
 
 struct
 {
@@ -54,6 +62,7 @@ struct
 } ATTR t5;
 int s5 = sizeof(t5);
 // CHECK: @s5 = global i32 1
+// CHECK-ARM: @s5 = global i32 1
 
 struct
 {
@@ -64,6 +73,7 @@ struct
 } ATTR t6;
 int s6 = sizeof(t6);
 // CHECK: @s6 = global i32 1
+// CHECK-ARM: @s6 = global i32 1
 
 struct
 {
@@ -84,6 +94,7 @@ struct
 } ATTR t7;
 int s7 = sizeof(t7);
 // CHECK: @s7 = global i32 9
+// CHECK-ARM: @s7 = global i32 9
 
 struct
 {
@@ -93,6 +104,7 @@ struct
 } ATTR t8;
 int s8 = sizeof(t8);
 // CHECK: @s8 = global i32 0
+// CHECK-ARM: @s8 = global i32 0
 
 struct
 {
@@ -125,6 +137,7 @@ struct
 } ATTR t9;
 int s9 = sizeof(t9);
 // CHECK: @s9 = global i32 28
+// CHECK-ARM: @s9 = global i32 28
 
 struct
 {
@@ -134,3 +147,33 @@ struct
 } ATTR t10;
 int s10 = sizeof(t10);
 // CHECK: @s10 = global i32 16
+// CHECK-ARM: @s10 = global i32 8
+
+// rdar://16041826 - ensure that ms_structs work correctly on a
+// !useBitFieldTypeAlignment() target
+struct {
+  unsigned int a : 31;
+  unsigned int b : 2;
+  unsigned int c;
+} ATTR t11;
+int s11 = sizeof(t11);
+// CHECK: @s11 = global i32 12
+// CHECK-ARM: @s11 = global i32 12
+
+struct {
+  unsigned char a : 3;
+  unsigned char b : 4;
+  unsigned short c : 6;
+} ATTR t12;
+int s12 = sizeof(t12);
+// CHECK: @s12 = global i32 4
+// CHECK-ARM: @s12 = global i32 4
+
+struct {
+  unsigned char a : 3;
+  unsigned char b : 4;
+  __attribute__((packed)) unsigned short c : 6;
+} ATTR t13;
+int s13 = sizeof(t13);
+// CHECK: @s13 = global i32 4
+// CHECK-ARM: @s13 = global i32 4