clang/test/CodeGen/packed-structure.c

   1 // RUN: %clang_cc1 -triple x86_64 -emit-llvm -o - %s | opt -S -passes=strip -o %t
   2 // RUN: FileCheck --check-prefix=CHECK-GLOBAL < %t %s
   3 // RUN: FileCheck --check-prefix=CHECK-FUNCTIONS < %t %s
   4
   5 struct s0 {
   6   int x;
   7   int y __attribute__((packed));
   8 };
   9
  10 // CHECK-GLOBAL: @s0_align_x ={{.*}} global i32 4
  11
  12 // CHECK-GLOBAL: @s0_align_y ={{.*}} global i32 1
  13
  14 // CHECK-GLOBAL: @s0_align ={{.*}} global i32 4
  15 int s0_align_x = __alignof(((struct s0*)0)->x);
  16 int s0_align_y = __alignof(((struct s0*)0)->y);
  17 int s0_align   = __alignof(struct s0);
  18
  19 // CHECK-FUNCTIONS-LABEL: define{{.*}} i32 @s0_load_x
  20 // CHECK-FUNCTIONS: [[s0_load_x:%.*]] = load i32, ptr {{.*}}, align 4
  21 // CHECK-FUNCTIONS: ret i32 [[s0_load_x]]
  22 int s0_load_x(struct s0 *a) { return a->x; }
  23 // FIXME: This seems like it should be align 1. This is actually something which
  24 // has changed in llvm-gcc recently, previously both x and y would be loaded
  25 // with align 1 (in 2363.1 at least).
  26 //
  27 // CHECK-FUNCTIONS-LABEL: define{{.*}} i32 @s0_load_y
  28 // CHECK-FUNCTIONS: [[s0_load_y:%.*]] = load i32, ptr {{.*}}, align 4
  29 // CHECK-FUNCTIONS: ret i32 [[s0_load_y]]
  30 int s0_load_y(struct s0 *a) { return a->y; }
  31 // CHECK-FUNCTIONS-LABEL: define{{.*}} void @s0_copy
  32 // CHECK-FUNCTIONS: call void @llvm.memcpy.p0.p0.i64(ptr align 4 {{.*}}, ptr align 4 {{.*}}, i64 8, i1 false)
  33 void s0_copy(struct s0 *a, struct s0 *b) { *b = *a; }
  34
  35 //
  36
  37 struct s1 {
  38   int x;
  39   int y;
  40 } __attribute__((packed));
  41
  42 // CHECK-GLOBAL: @s1_align_x ={{.*}} global i32 1
  43 // CHECK-GLOBAL: @s1_align_y ={{.*}} global i32 1
  44 // CHECK-GLOBAL: @s1_align ={{.*}} global i32 1
  45 int s1_align_x = __alignof(((struct s1*)0)->x);
  46 int s1_align_y = __alignof(((struct s1*)0)->y);
  47 int s1_align   = __alignof(struct s1);
  48
  49 // CHECK-FUNCTIONS-LABEL: define{{.*}} i32 @s1_load_x
  50 // CHECK-FUNCTIONS: [[s1_load_x:%.*]] = load i32, ptr {{.*}}, align 1
  51 // CHECK-FUNCTIONS: ret i32 [[s1_load_x]]
  52 int s1_load_x(struct s1 *a) { return a->x; }
  53 // CHECK-FUNCTIONS-LABEL: define{{.*}} i32 @s1_load_y
  54 // CHECK-FUNCTIONS: [[s1_load_y:%.*]] = load i32, ptr {{.*}}, align 1
  55 // CHECK-FUNCTIONS: ret i32 [[s1_load_y]]
  56 int s1_load_y(struct s1 *a) { return a->y; }
  57 // CHECK-FUNCTIONS-LABEL: define{{.*}} void @s1_copy
  58 // CHECK-FUNCTIONS: call void @llvm.memcpy.p0.p0.i64(ptr {{.*}}, ptr {{.*}}, i64 8, i1 false)
  59 void s1_copy(struct s1 *a, struct s1 *b) { *b = *a; }
  60
  61 //
  62
  63 #pragma pack(push,2)
  64 struct s2 {
  65   int x;
  66   int y;
  67 };
  68 #pragma pack(pop)
  69
  70 // CHECK-GLOBAL: @s2_align_x ={{.*}} global i32 2
  71 // CHECK-GLOBAL: @s2_align_y ={{.*}} global i32 2
  72 // CHECK-GLOBAL: @s2_align ={{.*}} global i32 2
  73 int s2_align_x = __alignof(((struct s2*)0)->x);
  74 int s2_align_y = __alignof(((struct s2*)0)->y);
  75 int s2_align   = __alignof(struct s2);
  76
  77 // CHECK-FUNCTIONS-LABEL: define{{.*}} i32 @s2_load_x
  78 // CHECK-FUNCTIONS: [[s2_load_y:%.*]] = load i32, ptr {{.*}}, align 2
  79 // CHECK-FUNCTIONS: ret i32 [[s2_load_y]]
  80 int s2_load_x(struct s2 *a) { return a->x; }
  81 // CHECK-FUNCTIONS-LABEL: define{{.*}} i32 @s2_load_y
  82 // CHECK-FUNCTIONS: [[s2_load_y:%.*]] = load i32, ptr {{.*}}, align 2
  83 // CHECK-FUNCTIONS: ret i32 [[s2_load_y]]
  84 int s2_load_y(struct s2 *a) { return a->y; }
  85 // CHECK-FUNCTIONS-LABEL: define{{.*}} void @s2_copy
  86 // CHECK-FUNCTIONS: call void @llvm.memcpy.p0.p0.i64(ptr align 2 {{.*}}, ptr align 2 {{.*}}, i64 8, i1 false)
  87 void s2_copy(struct s2 *a, struct s2 *b) { *b = *a; }
  88
  89 struct __attribute__((packed, aligned)) s3 {
  90   short aShort;
  91   int anInt;
  92 };
  93 // CHECK-GLOBAL: @s3_1 ={{.*}} global i32 1
  94 int s3_1 = __alignof(((struct s3*) 0)->anInt);
  95 // CHECK-FUNCTIONS-LABEL: define{{.*}} i32 @test3(
  96 int test3(struct s3 *ptr) {
  97   // CHECK-FUNCTIONS:      [[PTR:%.*]] = getelementptr inbounds {{%.*}}, ptr {{%.*}}, i32 0, i32 1
  98   // CHECK-FUNCTIONS-NEXT: load i32, ptr [[PTR]], align 2
  99   return ptr->anInt;
 100 }