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// RUN: %clang_cc1 -fblocks -triple x86_64-apple-darwin9 %s -emit-llvm -o - | FileCheck %s -check-prefix=X64
// RUN: %clang_cc1 -fblocks -triple i686-apple-darwin9 %s -emit-llvm -o - | FileCheck %s -check-prefix=X32
// X64: internal constant {{.*}} { i8** @_NSConcreteGlobalBlock, i32 1879048192
// X64: store i32 1610612736, i32* %want
// X32: @_NSConcreteGlobalBlock, i32 1879048192, i32 0,
// X32: store i32 1610612736, i32* %want
// rdar://7677537
int printf(const char *, ...);
void *malloc(__SIZE_TYPE__ size);
typedef struct bigbig {
int array[512];
char more[32];
} BigStruct_t;
BigStruct_t (^global)(void) = ^{ return *(BigStruct_t *)malloc(sizeof(struct bigbig)); };
const char * getBlockSignature(void *);
BigStruct_t foo(int param) {
BigStruct_t x;
BigStruct_t (^f)(int) = ^(int param) {
BigStruct_t *result = malloc(sizeof(BigStruct_t));
result->array[23] = param;
return *result;
};
getBlockSignature(f);
return x;
}
enum {
BLOCK_HAS_COPY_DISPOSE = (1 << 25),
BLOCK_HAS_CXX_OBJ = (1 << 26),
BLOCK_IS_GLOBAL = (1 << 28),
BLOCK_USE_STRET = (1 << 29),
BLOCK_HAS_OBJC_TYPE = (1 << 30)
};
struct block_descriptor_big {
unsigned long int reserved;
unsigned long int size;
void (*copy)(void *dst, void *src); // conditional on BLOCK_HAS_COPY_DISPOSE
void (*dispose)(void *); // conditional on BLOCK_HAS_COPY_DISPOSE
const char *signature; // conditional on BLOCK_HAS_OBJC
const char *layout; // conditional on BLOCK_HAS_OBJC
};
struct block_descriptor_small {
unsigned long int reserved;
unsigned long int size;
const char *signature; // conditional on BLOCK_HAS_OBJC
const char *layout; // conditional on BLOCK_HAS_OBJC
};
struct block_layout_abi { // can't change
void *isa;
int flags;
int reserved;
void (*invoke)(void *, ...);
struct block_descriptor_big *descriptor;
};
const char *getBlockSignature(void *block) {
struct block_layout_abi *layout = (struct block_layout_abi *)block;
if ((layout->flags & BLOCK_HAS_OBJC_TYPE) != BLOCK_HAS_OBJC_TYPE) return 0;
if (layout->flags & BLOCK_HAS_COPY_DISPOSE)
return layout->descriptor->signature;
else
return ((struct block_descriptor_small *)layout->descriptor)->signature;
}
int usesStruct(void *block) {
struct block_layout_abi *layout = (struct block_layout_abi *)block;
int want = BLOCK_HAS_OBJC_TYPE | BLOCK_USE_STRET;
return (layout->flags & want) == want;
}
int main(int argc, char *argv[]) {
printf("desired global flags: %d\n", BLOCK_USE_STRET | BLOCK_IS_GLOBAL | BLOCK_HAS_OBJC_TYPE);
printf("desired stack flags: %d\n", BLOCK_USE_STRET | BLOCK_HAS_OBJC_TYPE);
printf("should be non-zero: %d\n", usesStruct(global));
BigStruct_t x;
BigStruct_t (^local)(int) = ^(int param) {
BigStruct_t *result = (BigStruct_t *)malloc(sizeof(BigStruct_t));
result->array[23] = argc;
return *result;
};
printf("should be non-zero: %d\n", usesStruct(global));
printf("should be non-zero: %d\n", usesStruct(local));
printf("should be zero: %d\n", usesStruct(^void(int x){ }));
return 0;
}
/*
desired global flags: 1879048192
desired stack flags: 1610612736
should be non-zero: 1
should be non-zero: 1
should be non-zero: 1
should be zero: 0
*/
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