diff options
| -rw-r--r-- | libcxxabi/include/cxxabi.h | 6 | ||||
| -rw-r--r-- | libcxxabi/src/cxa_guard.cpp | 68 |
2 files changed, 68 insertions, 6 deletions
diff --git a/libcxxabi/include/cxxabi.h b/libcxxabi/include/cxxabi.h index ec69b55ce0f..b92b2faf072 100644 --- a/libcxxabi/include/cxxabi.h +++ b/libcxxabi/include/cxxabi.h @@ -61,9 +61,15 @@ extern LIBCXXABI_NORETURN void __cxa_pure_virtual(void); extern LIBCXXABI_NORETURN void __cxa_deleted_virtual(void); // 3.3.2 One-time Construction API +#ifdef LIBCXXABI_ARMEABI +extern int __cxa_guard_acquire(uint32_t*); +extern void __cxa_guard_release(uint32_t*); +extern void __cxa_guard_abort(uint32_t*); +#else extern int __cxa_guard_acquire(uint64_t*); extern void __cxa_guard_release(uint64_t*); extern void __cxa_guard_abort(uint64_t*); +#endif // 3.3.3 Array Construction and Destruction API extern void* __cxa_vec_new(size_t element_count, diff --git a/libcxxabi/src/cxa_guard.cpp b/libcxxabi/src/cxa_guard.cpp index 64abda1e1d4..063d250ead5 100644 --- a/libcxxabi/src/cxa_guard.cpp +++ b/libcxxabi/src/cxa_guard.cpp @@ -20,6 +20,38 @@ namespace __cxxabiv1 namespace { +#if LIBCXXABI_ARMEABI + +// A 32-bit, 4-byte-aligned static data value. The least significant 2 bits must +// be statically initialized to 0. +typedef uint32_t guard_type; + +// Test the lowest bit. +inline bool is_initialized(guard_type* guard_object) { + return (*guard_object) & 1; +} + +inline void set_initialized(guard_type* guard_object) { + *guard_object |= 1; +} + +#else + +typedef uint64_t guard_type; + +bool is_initialized(guard_type* guard_object) { + char* initialized = (char*)guard_object; + return *initialized; +} + +void set_initialized(guard_type* guard_object) { + char* initialized = (char*)guard_object; + *initialized = 1; +} + +#endif + + void abort_message(const char* s) { fputs(s, stderr); @@ -96,6 +128,31 @@ set_lock(uint64_t& x, lock_type y) x = f.guard; } +inline +lock_type +get_lock(uint32_t x) +{ + union + { + uint32_t guard; + uint8_t lock[2]; + } f = {x}; + return f.lock[1] != 0; +} + +inline +void +set_lock(uint32_t& x, lock_type y) +{ + union + { + uint32_t guard; + uint8_t lock[2]; + } f = {0}; + f.lock[1] = y; + x = f.guard; +} + #endif // __APPLE__ } // unnamed namespace @@ -103,7 +160,7 @@ set_lock(uint64_t& x, lock_type y) extern "C" { -int __cxa_guard_acquire(uint64_t* guard_object) +int __cxa_guard_acquire(guard_type* guard_object) { char* initialized = (char*)guard_object; if (pthread_mutex_lock(&guard_mut)) @@ -125,7 +182,7 @@ int __cxa_guard_acquire(uint64_t* guard_object) abort_message("__cxa_guard_acquire condition variable wait failed"); lock = get_lock(*guard_object); } while (lock); - result = *initialized == 0; + result = !is_initialized(guard_object); if (result) set_lock(*guard_object, id); } @@ -145,20 +202,19 @@ int __cxa_guard_acquire(uint64_t* guard_object) return result; } -void __cxa_guard_release(uint64_t* guard_object) +void __cxa_guard_release(guard_type* guard_object) { - char* initialized = (char*)guard_object; if (pthread_mutex_lock(&guard_mut)) abort_message("__cxa_guard_release failed to acquire mutex"); *guard_object = 0; - *initialized = 1; + set_initialized(guard_object); if (pthread_mutex_unlock(&guard_mut)) abort_message("__cxa_guard_release failed to release mutex"); if (pthread_cond_broadcast(&guard_cv)) abort_message("__cxa_guard_release failed to broadcast condition variable"); } -void __cxa_guard_abort(uint64_t* guard_object) +void __cxa_guard_abort(guard_type* guard_object) { if (pthread_mutex_lock(&guard_mut)) abort_message("__cxa_guard_abort failed to acquire mutex"); |
