Reland "Retire GCC FORTIFY."
This reverts commit 4dbe8fc22f96868d3e5164653a6387b86b163673.
The angler/bullhead builds are now dead, so this can go in.
Bug: https://issuetracker.google.com/74404306
Change-Id: I130cdcd6375b6125cb8a1e63a4a540b0dbe41ceb
diff --git a/libc/include/stdatomic.h b/libc/include/stdatomic.h
index 013407e..3c61334 100644
--- a/libc/include/stdatomic.h
+++ b/libc/include/stdatomic.h
@@ -33,11 +33,7 @@
#include <sys/cdefs.h>
#if defined(__cplusplus) && __cplusplus >= 201103L && defined(_USING_LIBCXX)
-# ifdef __clang__
-# if __has_feature(cxx_atomic)
-# define _STDATOMIC_HAVE_ATOMIC
-# endif
-# else /* gcc */
+# if __has_feature(cxx_atomic)
# define _STDATOMIC_HAVE_ATOMIC
# endif
#endif
@@ -150,20 +146,6 @@
# include <uchar.h> /* For char16_t and char32_t. */
#endif
-
-#ifdef __clang__
-# if __has_extension(c_atomic) || __has_extension(cxx_atomic)
-# define __CLANG_ATOMICS
-# else
-# error "stdatomic.h does not support your compiler"
-# endif
-# if __has_builtin(__sync_swap)
-# define __HAS_BUILTIN_SYNC_SWAP
-# endif
-#else
-# define __GNUC_ATOMICS
-#endif
-
/*
* 7.17.1 Atomic lock-free macros.
*/
@@ -203,13 +185,8 @@
* 7.17.2 Initialization.
*/
-#if defined(__CLANG_ATOMICS)
#define ATOMIC_VAR_INIT(value) (value)
#define atomic_init(obj, value) __c11_atomic_init(obj, value)
-#else
-#define ATOMIC_VAR_INIT(value) { .__val = (value) }
-#define atomic_init(obj, value) ((void)((obj)->__val = (value)))
-#endif
/*
* Clang and recent GCC both provide predefined macros for the memory
@@ -258,63 +235,24 @@
* 7.17.4 Fences.
*/
-static __inline void
-atomic_thread_fence(memory_order __order __attribute__((unused)))
-{
-
-#ifdef __CLANG_ATOMICS
+static __inline void atomic_thread_fence(memory_order __order __attribute__((unused))) {
__c11_atomic_thread_fence(__order);
-#elif defined(__GNUC_ATOMICS)
- __atomic_thread_fence(__order);
-#else
- __sync_synchronize();
-#endif
}
-static __inline void
-atomic_signal_fence(memory_order __order __attribute__((unused)))
-{
-
-#ifdef __CLANG_ATOMICS
+static __inline void atomic_signal_fence(memory_order __order __attribute__((unused))) {
__c11_atomic_signal_fence(__order);
-#elif defined(__GNUC_ATOMICS)
- __atomic_signal_fence(__order);
-#else
- __asm volatile ("" ::: "memory");
-#endif
}
/*
* 7.17.5 Lock-free property.
*/
-#if defined(_KERNEL)
-/* Atomics in kernelspace are always lock-free. */
-#define atomic_is_lock_free(obj) \
- ((void)(obj), (_Bool)1)
-#elif defined(__CLANG_ATOMICS)
-#define atomic_is_lock_free(obj) \
- __c11_atomic_is_lock_free(sizeof(*(obj)))
-#elif defined(__GNUC_ATOMICS)
-#define atomic_is_lock_free(obj) \
- __atomic_is_lock_free(sizeof((obj)->__val), &(obj)->__val)
-#else
-#define atomic_is_lock_free(obj) \
- ((void)(obj), sizeof((obj)->__val) <= sizeof(void *))
-#endif
+#define atomic_is_lock_free(obj) __c11_atomic_is_lock_free(sizeof(*(obj)))
/*
* 7.17.6 Atomic integer types.
*/
-#ifndef __CLANG_ATOMICS
-/*
- * No native support for _Atomic(). Place object in structure to prevent
- * most forms of direct non-atomic access.
- */
-#define _Atomic(T) struct { T volatile __val; }
-#endif
-
typedef _Atomic(bool) atomic_bool;
typedef _Atomic(char) atomic_char;
typedef _Atomic(signed char) atomic_schar;
@@ -363,7 +301,6 @@
* Compiler-specific operations.
*/
-#if defined(__CLANG_ATOMICS)
#define atomic_compare_exchange_strong_explicit(object, expected, \
desired, success, failure) \
__c11_atomic_compare_exchange_strong(object, expected, desired, \
@@ -388,91 +325,11 @@
__c11_atomic_load(object, order)
#define atomic_store_explicit(object, desired, order) \
__c11_atomic_store(object, desired, order)
-#elif defined(__GNUC_ATOMICS)
-#define atomic_compare_exchange_strong_explicit(object, expected, \
- desired, success, failure) \
- __atomic_compare_exchange_n(&(object)->__val, expected, \
- desired, 0, success, failure)
-#define atomic_compare_exchange_weak_explicit(object, expected, \
- desired, success, failure) \
- __atomic_compare_exchange_n(&(object)->__val, expected, \
- desired, 1, success, failure)
-#define atomic_exchange_explicit(object, desired, order) \
- __atomic_exchange_n(&(object)->__val, desired, order)
-#define atomic_fetch_add_explicit(object, operand, order) \
- __atomic_fetch_add(&(object)->__val, operand, order)
-#define atomic_fetch_and_explicit(object, operand, order) \
- __atomic_fetch_and(&(object)->__val, operand, order)
-#define atomic_fetch_or_explicit(object, operand, order) \
- __atomic_fetch_or(&(object)->__val, operand, order)
-#define atomic_fetch_sub_explicit(object, operand, order) \
- __atomic_fetch_sub(&(object)->__val, operand, order)
-#define atomic_fetch_xor_explicit(object, operand, order) \
- __atomic_fetch_xor(&(object)->__val, operand, order)
-#define atomic_load_explicit(object, order) \
- __atomic_load_n(&(object)->__val, order)
-#define atomic_store_explicit(object, desired, order) \
- __atomic_store_n(&(object)->__val, desired, order)
-#else
-#define __atomic_apply_stride(object, operand) \
- (((__typeof__((object)->__val))0) + (operand))
-#define atomic_compare_exchange_strong_explicit(object, expected, \
- desired, success, failure) __extension__ ({ \
- __typeof__(expected) __ep = (expected); \
- __typeof__(*__ep) __e = *__ep; \
- (void)(success); (void)(failure); \
- (bool)((*__ep = __sync_val_compare_and_swap(&(object)->__val, \
- __e, desired)) == __e); \
-})
-#define atomic_compare_exchange_weak_explicit(object, expected, \
- desired, success, failure) \
- atomic_compare_exchange_strong_explicit(object, expected, \
- desired, success, failure)
-#ifdef __HAS_BUILTIN_SYNC_SWAP
-/* Clang provides a full-barrier atomic exchange - use it if available. */
-#define atomic_exchange_explicit(object, desired, order) \
- ((void)(order), __sync_swap(&(object)->__val, desired))
-#else
-/*
- * __sync_lock_test_and_set() is only an acquire barrier in theory (although in
- * practice it is usually a full barrier) so we need an explicit barrier before
- * it.
- */
-#define atomic_exchange_explicit(object, desired, order) \
-__extension__ ({ \
- __typeof__(object) __o = (object); \
- __typeof__(desired) __d = (desired); \
- (void)(order); \
- __sync_synchronize(); \
- __sync_lock_test_and_set(&(__o)->__val, __d); \
-})
-#endif
-#define atomic_fetch_add_explicit(object, operand, order) \
- ((void)(order), __sync_fetch_and_add(&(object)->__val, \
- __atomic_apply_stride(object, operand)))
-#define atomic_fetch_and_explicit(object, operand, order) \
- ((void)(order), __sync_fetch_and_and(&(object)->__val, operand))
-#define atomic_fetch_or_explicit(object, operand, order) \
- ((void)(order), __sync_fetch_and_or(&(object)->__val, operand))
-#define atomic_fetch_sub_explicit(object, operand, order) \
- ((void)(order), __sync_fetch_and_sub(&(object)->__val, \
- __atomic_apply_stride(object, operand)))
-#define atomic_fetch_xor_explicit(object, operand, order) \
- ((void)(order), __sync_fetch_and_xor(&(object)->__val, operand))
-#define atomic_load_explicit(object, order) \
- ((void)(order), __sync_fetch_and_add(&(object)->__val, 0))
-#define atomic_store_explicit(object, desired, order) \
- ((void)atomic_exchange_explicit(object, desired, order))
-#endif
/*
* Convenience functions.
- *
- * Don't provide these in kernel space. In kernel space, we should be
- * disciplined enough to always provide explicit barriers.
*/
-#ifndef _KERNEL
#define atomic_compare_exchange_strong(object, expected, desired) \
atomic_compare_exchange_strong_explicit(object, expected, \
desired, memory_order_seq_cst, memory_order_seq_cst)
@@ -495,7 +352,6 @@
atomic_load_explicit(object, memory_order_seq_cst)
#define atomic_store(object, desired) \
atomic_store_explicit(object, desired, memory_order_seq_cst)
-#endif /* !_KERNEL */
/*
* 7.17.8 Atomic flag type and operations.
@@ -510,36 +366,21 @@
#define ATOMIC_FLAG_INIT { ATOMIC_VAR_INIT(false) }
-static __inline bool
-atomic_flag_test_and_set_explicit(volatile atomic_flag *__object,
- memory_order __order)
-{
+static __inline bool atomic_flag_test_and_set_explicit(volatile atomic_flag *__object, memory_order __order) {
return (atomic_exchange_explicit(&__object->__flag, 1, __order));
}
-static __inline void
-atomic_flag_clear_explicit(volatile atomic_flag *__object, memory_order __order)
-{
-
+static __inline void atomic_flag_clear_explicit(volatile atomic_flag *__object, memory_order __order) {
atomic_store_explicit(&__object->__flag, 0, __order);
}
-#ifndef _KERNEL
-static __inline bool
-atomic_flag_test_and_set(volatile atomic_flag *__object)
-{
-
- return (atomic_flag_test_and_set_explicit(__object,
- memory_order_seq_cst));
+static __inline bool atomic_flag_test_and_set(volatile atomic_flag *__object) {
+ return (atomic_flag_test_and_set_explicit(__object, memory_order_seq_cst));
}
-static __inline void
-atomic_flag_clear(volatile atomic_flag *__object)
-{
-
+static __inline void atomic_flag_clear(volatile atomic_flag *__object) {
atomic_flag_clear_explicit(__object, memory_order_seq_cst);
}
-#endif /* !_KERNEL */
#endif /* <atomic> unavailable */