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[5.9][Runtime] Redeclare _dyld_lookup_section_info as weak, don't use enum _dyld_section_location_kind. #68040

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Merged
merged 2 commits into from
Aug 23, 2023
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[5.9][Runtime] Redeclare _dyld_lookup_section_info as weak, don't use enum _dyld_section_location_kind. #68040

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c9ccb67
[Runtime] Avoid referring to enum _dyld_section_location_kind.
mikeash Mar 2, 2023
4deb127
[Runtime] Redeclare _dyld_lookup_section_info as weak.
mikeash Mar 29, 2023
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63 changes: 41 additions & 22 deletions stdlib/public/runtime/ImageInspectionMachO.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -49,7 +49,26 @@ enum _dyld_section_location_kind {

#endif

#if !OBJC_ADDLOADIMAGEFUNC2_DEFINED
// Bring our own definition of _dyld_section_location constants in case we're
// using an older SDK that doesn't have them.
#define _dyld_section_location_text_swift5_protos 0
#define _dyld_section_location_text_swift5_proto 1
#define _dyld_section_location_text_swift5_types 2
#define _dyld_section_location_text_swift5_replace 3
#define _dyld_section_location_text_swift5_replace2 4
#define _dyld_section_location_text_swift5_ac_funcs 5

#if OBJC_ADDLOADIMAGEFUNC2_DEFINED
// Redefine _dyld_lookup_section_info as weak so we can build against it but
// still run when it's not present at runtime. Note that we don't have to check
// for its presence at runtime, as it's guaranteed to be available if we get
// the callbacks from objc_addLoadImageFunc2.
LLVM_ATTRIBUTE_WEAK
struct _dyld_section_info_result
_dyld_lookup_section_info(const struct mach_header *mh,
_dyld_section_location_info_t locationHandle,
enum _dyld_section_location_kind kind);
#else
// If we don't have objc_addLoadImageFunc2, fall back to objc_addLoadImageFunc.
// Use a #define so we don't have to conditionalize the calling code below.
#define objc_addLoadImageFunc2 objc_addLoadImageFunc
Expand Down Expand Up @@ -79,8 +98,7 @@ using mach_header_platform = mach_header;
#endif

// Callback for objc_addLoadImageFunc that just takes a mach_header.
template <const char *SEGMENT_NAME, const char *SECTION_NAME,
enum _dyld_section_location_kind SECTION_KIND,
template <const char *SEGMENT_NAME, const char *SECTION_NAME, int SECTION_KIND,
void CONSUME_BLOCK(const void *baseAddress, const void *start,
uintptr_t size)>
void addImageCallback(const mach_header *mh) {
Expand All @@ -102,8 +120,7 @@ void addImageCallback(const mach_header *mh) {

// Callback for objc_addLoadImageFunc2 that takes a mach_header and dyld info.
#if OBJC_ADDLOADIMAGEFUNC2_DEFINED
template <const char *SEGMENT_NAME, const char *SECTION_NAME,
enum _dyld_section_location_kind SECTION_KIND,
template <const char *SEGMENT_NAME, const char *SECTION_NAME, int SECTION_KIND,
void CONSUME_BLOCK(const void *baseAddress, const void *start,
uintptr_t size)>
void addImageCallback(const mach_header *mh,
Expand All @@ -112,16 +129,17 @@ void addImageCallback(const mach_header *mh,
assert(mh->magic == MH_MAGIC_64 && "loaded non-64-bit image?!");
#endif

auto result = _dyld_lookup_section_info(mh, dyldInfo, SECTION_KIND);
auto result = _dyld_lookup_section_info(
mh, dyldInfo,
static_cast<enum _dyld_section_location_kind>(SECTION_KIND));
if (result.buffer)
CONSUME_BLOCK(mh, result.buffer, result.bufferSize);
}
#endif

// Callback for _dyld_register_func_for_add_image that takes a mach_header and a
// slide.
template <const char *SEGMENT_NAME, const char *SECTION_NAME,
enum _dyld_section_location_kind SECTION_KIND,
template <const char *SEGMENT_NAME, const char *SECTION_NAME, int SECTION_KIND,
void CONSUME_BLOCK(const void *baseAddress, const void *start,
uintptr_t size)>
void addImageCallback(const mach_header *mh, intptr_t vmaddr_slide) {
Expand All @@ -132,11 +150,10 @@ void addImageCallback(const mach_header *mh, intptr_t vmaddr_slide) {

template <const char *SEGMENT_NAME, const char *SECTION_NAME,
const char *SEGMENT_NAME2, const char *SECTION_NAME2,
enum _dyld_section_location_kind SECTION_KIND,
enum _dyld_section_location_kind SECTION_KIND2,
void CONSUME_BLOCK(const void *baseAddress,
const void *start, uintptr_t size,
const void *start2, uintptr_t size2)>
int SECTION_KIND, int SECTION_KIND2,
void CONSUME_BLOCK(const void *baseAddress, const void *start,
uintptr_t size, const void *start2,
uintptr_t size2)>
void addImageCallback2Sections(const mach_header *mh) {
#if __POINTER_WIDTH__ == 64
assert(mh->magic == MH_MAGIC_64 && "loaded non-64-bit image?!");
Expand Down Expand Up @@ -168,23 +185,26 @@ void addImageCallback2Sections(const mach_header *mh) {
#if OBJC_ADDLOADIMAGEFUNC2_DEFINED
template <const char *SEGMENT_NAME, const char *SECTION_NAME,
const char *SEGMENT_NAME2, const char *SECTION_NAME2,
enum _dyld_section_location_kind SECTION_KIND,
enum _dyld_section_location_kind SECTION_KIND2,
void CONSUME_BLOCK(const void *baseAddress,
const void *start, uintptr_t size,
const void *start2, uintptr_t size2)>
int SECTION_KIND, int SECTION_KIND2,
void CONSUME_BLOCK(const void *baseAddress, const void *start,
uintptr_t size, const void *start2,
uintptr_t size2)>
void addImageCallback2Sections(const mach_header *mh,
struct _dyld_section_location_info_s *dyldInfo) {
#if __POINTER_WIDTH__ == 64
assert(mh->magic == MH_MAGIC_64 && "loaded non-64-bit image?!");
#endif

// Look for a section.
auto result = _dyld_lookup_section_info(mh, dyldInfo, SECTION_KIND);
auto result = _dyld_lookup_section_info(
mh, dyldInfo,
static_cast<enum _dyld_section_location_kind>(SECTION_KIND));
if (!result.buffer)
return;

auto result2 = _dyld_lookup_section_info(mh, dyldInfo, SECTION_KIND2);
auto result2 = _dyld_lookup_section_info(
mh, dyldInfo,
static_cast<enum _dyld_section_location_kind>(SECTION_KIND2));
// No NULL check here, we allow this one not to be present. dyld gives us
// a NULL pointer and 0 size when the section isn't in the dylib so we don't
// need to zero anything out.
Expand All @@ -198,8 +218,7 @@ void addImageCallback2Sections(const mach_header *mh,
// slide.
template <const char *SEGMENT_NAME, const char *SECTION_NAME,
const char *SEGMENT_NAME2, const char *SECTION_NAME2,
enum _dyld_section_location_kind SECTION_KIND,
enum _dyld_section_location_kind SECTION_KIND2,
int SECTION_KIND, int SECTION_KIND2,
void CONSUME_BLOCK(const void *baseAddress, const void *start,
uintptr_t size, const void *start2,
uintptr_t size2)>
Expand Down