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authorAnton Samokhvalov <pg83@yandex.ru>2022-02-10 16:45:15 +0300
committerDaniil Cherednik <dcherednik@yandex-team.ru>2022-02-10 16:45:15 +0300
commit72cb13b4aff9bc9cf22e49251bc8fd143f82538f (patch)
treeda2c34829458c7d4e74bdfbdf85dff449e9e7fb8 /contrib/libs/cxxsupp/builtins/atomic.c
parent778e51ba091dc39e7b7fcab2b9cf4dbedfb6f2b5 (diff)
downloadydb-72cb13b4aff9bc9cf22e49251bc8fd143f82538f.tar.gz
Restoring authorship annotation for Anton Samokhvalov <pg83@yandex.ru>. Commit 1 of 2.
Diffstat (limited to 'contrib/libs/cxxsupp/builtins/atomic.c')
-rw-r--r--contrib/libs/cxxsupp/builtins/atomic.c658
1 files changed, 329 insertions, 329 deletions
diff --git a/contrib/libs/cxxsupp/builtins/atomic.c b/contrib/libs/cxxsupp/builtins/atomic.c
index f1ddc3e0c5..42753ee809 100644
--- a/contrib/libs/cxxsupp/builtins/atomic.c
+++ b/contrib/libs/cxxsupp/builtins/atomic.c
@@ -1,331 +1,331 @@
-/*===-- atomic.c - Implement support functions for atomic operations.------===
- *
- * The LLVM Compiler Infrastructure
- *
- * This file is dual licensed under the MIT and the University of Illinois Open
- * Source Licenses. See LICENSE.TXT for details.
- *
- *===----------------------------------------------------------------------===
- *
- * atomic.c defines a set of functions for performing atomic accesses on
- * arbitrary-sized memory locations. This design uses locks that should
- * be fast in the uncontended case, for two reasons:
+/*===-- atomic.c - Implement support functions for atomic operations.------===
*
- * 1) This code must work with C programs that do not link to anything
- * (including pthreads) and so it should not depend on any pthread
- * functions.
- * 2) Atomic operations, rather than explicit mutexes, are most commonly used
- * on code where contended operations are rate.
+ * The LLVM Compiler Infrastructure
*
- * To avoid needing a per-object lock, this code allocates an array of
- * locks and hashes the object pointers to find the one that it should use.
- * For operations that must be atomic on two locations, the lower lock is
- * always acquired first, to avoid deadlock.
- *
- *===----------------------------------------------------------------------===
- */
-
-#include <stdint.h>
-#include <string.h>
-
-#include "assembly.h"
-
-// Clang objects if you redefine a builtin. This little hack allows us to
-// define a function with the same name as an intrinsic.
-#pragma redefine_extname __atomic_load_c SYMBOL_NAME(__atomic_load)
-#pragma redefine_extname __atomic_store_c SYMBOL_NAME(__atomic_store)
-#pragma redefine_extname __atomic_exchange_c SYMBOL_NAME(__atomic_exchange)
-#pragma redefine_extname __atomic_compare_exchange_c SYMBOL_NAME(__atomic_compare_exchange)
-
-/// Number of locks. This allocates one page on 32-bit platforms, two on
-/// 64-bit. This can be specified externally if a different trade between
-/// memory usage and contention probability is required for a given platform.
-#ifndef SPINLOCK_COUNT
-#define SPINLOCK_COUNT (1<<10)
-#endif
-static const long SPINLOCK_MASK = SPINLOCK_COUNT - 1;
-
-////////////////////////////////////////////////////////////////////////////////
-// Platform-specific lock implementation. Falls back to spinlocks if none is
-// defined. Each platform should define the Lock type, and corresponding
-// lock() and unlock() functions.
-////////////////////////////////////////////////////////////////////////////////
-#ifdef __FreeBSD__
-#include <errno.h>
-#include <sys/types.h>
-#include <machine/atomic.h>
-#include <sys/umtx.h>
-typedef struct _usem Lock;
-__inline static void unlock(Lock *l) {
- __c11_atomic_store((_Atomic(uint32_t)*)&l->_count, 1, __ATOMIC_RELEASE);
- __c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
- if (l->_has_waiters)
- _umtx_op(l, UMTX_OP_SEM_WAKE, 1, 0, 0);
-}
-__inline static void lock(Lock *l) {
- uint32_t old = 1;
- while (!__c11_atomic_compare_exchange_weak((_Atomic(uint32_t)*)&l->_count, &old,
- 0, __ATOMIC_ACQUIRE, __ATOMIC_RELAXED)) {
- _umtx_op(l, UMTX_OP_SEM_WAIT, 0, 0, 0);
- old = 1;
- }
-}
-/// locks for atomic operations
-static Lock locks[SPINLOCK_COUNT] = { [0 ... SPINLOCK_COUNT-1] = {0,1,0} };
-
-#elif defined(__APPLE__)
-#include <libkern/OSAtomic.h>
-typedef OSSpinLock Lock;
-__inline static void unlock(Lock *l) {
- OSSpinLockUnlock(l);
-}
-/// Locks a lock. In the current implementation, this is potentially
-/// unbounded in the contended case.
-__inline static void lock(Lock *l) {
- OSSpinLockLock(l);
-}
-static Lock locks[SPINLOCK_COUNT]; // initialized to OS_SPINLOCK_INIT which is 0
-
-#else
-typedef _Atomic(uintptr_t) Lock;
-/// Unlock a lock. This is a release operation.
-__inline static void unlock(Lock *l) {
- __c11_atomic_store(l, 0, __ATOMIC_RELEASE);
-}
-/// Locks a lock. In the current implementation, this is potentially
-/// unbounded in the contended case.
-__inline static void lock(Lock *l) {
- uintptr_t old = 0;
- while (!__c11_atomic_compare_exchange_weak(l, &old, 1, __ATOMIC_ACQUIRE,
- __ATOMIC_RELAXED))
- old = 0;
-}
-/// locks for atomic operations
-static Lock locks[SPINLOCK_COUNT];
-#endif
-
-
-/// Returns a lock to use for a given pointer.
-static __inline Lock *lock_for_pointer(void *ptr) {
- intptr_t hash = (intptr_t)ptr;
- // Disregard the lowest 4 bits. We want all values that may be part of the
- // same memory operation to hash to the same value and therefore use the same
- // lock.
- hash >>= 4;
- // Use the next bits as the basis for the hash
- intptr_t low = hash & SPINLOCK_MASK;
- // Now use the high(er) set of bits to perturb the hash, so that we don't
- // get collisions from atomic fields in a single object
- hash >>= 16;
- hash ^= low;
- // Return a pointer to the word to use
- return locks + (hash & SPINLOCK_MASK);
-}
-
-/// Macros for determining whether a size is lock free. Clang can not yet
-/// codegen __atomic_is_lock_free(16), so for now we assume 16-byte values are
-/// not lock free.
-#define IS_LOCK_FREE_1 __c11_atomic_is_lock_free(1)
-#define IS_LOCK_FREE_2 __c11_atomic_is_lock_free(2)
-#define IS_LOCK_FREE_4 __c11_atomic_is_lock_free(4)
-#define IS_LOCK_FREE_8 __c11_atomic_is_lock_free(8)
-#define IS_LOCK_FREE_16 0
-
-/// Macro that calls the compiler-generated lock-free versions of functions
-/// when they exist.
-#define LOCK_FREE_CASES() \
- do {\
- switch (size) {\
- case 2:\
- if (IS_LOCK_FREE_2) {\
- LOCK_FREE_ACTION(uint16_t);\
- }\
- case 4:\
- if (IS_LOCK_FREE_4) {\
- LOCK_FREE_ACTION(uint32_t);\
- }\
- case 8:\
- if (IS_LOCK_FREE_8) {\
- LOCK_FREE_ACTION(uint64_t);\
- }\
- case 16:\
- if (IS_LOCK_FREE_16) {\
- /* FIXME: __uint128_t isn't available on 32 bit platforms.
- LOCK_FREE_ACTION(__uint128_t);*/\
- }\
- }\
- } while (0)
-
-
-/// An atomic load operation. This is atomic with respect to the source
-/// pointer only.
-void __atomic_load_c(int size, void *src, void *dest, int model) {
-#define LOCK_FREE_ACTION(type) \
- *((type*)dest) = __c11_atomic_load((_Atomic(type)*)src, model);\
- return;
- LOCK_FREE_CASES();
-#undef LOCK_FREE_ACTION
- Lock *l = lock_for_pointer(src);
- lock(l);
- memcpy(dest, src, size);
- unlock(l);
-}
-
-/// An atomic store operation. This is atomic with respect to the destination
-/// pointer only.
-void __atomic_store_c(int size, void *dest, void *src, int model) {
-#define LOCK_FREE_ACTION(type) \
- __c11_atomic_store((_Atomic(type)*)dest, *(type*)dest, model);\
- return;
- LOCK_FREE_CASES();
-#undef LOCK_FREE_ACTION
- Lock *l = lock_for_pointer(dest);
- lock(l);
- memcpy(dest, src, size);
- unlock(l);
-}
-
-/// Atomic compare and exchange operation. If the value at *ptr is identical
-/// to the value at *expected, then this copies value at *desired to *ptr. If
-/// they are not, then this stores the current value from *ptr in *expected.
-///
-/// This function returns 1 if the exchange takes place or 0 if it fails.
-int __atomic_compare_exchange_c(int size, void *ptr, void *expected,
- void *desired, int success, int failure) {
-#define LOCK_FREE_ACTION(type) \
- return __c11_atomic_compare_exchange_strong((_Atomic(type)*)ptr, (type*)expected,\
- *(type*)desired, success, failure)
- LOCK_FREE_CASES();
-#undef LOCK_FREE_ACTION
- Lock *l = lock_for_pointer(ptr);
- lock(l);
- if (memcmp(ptr, expected, size) == 0) {
- memcpy(ptr, desired, size);
- unlock(l);
- return 1;
- }
- memcpy(expected, ptr, size);
- unlock(l);
- return 0;
-}
-
-/// Performs an atomic exchange operation between two pointers. This is atomic
-/// with respect to the target address.
-void __atomic_exchange_c(int size, void *ptr, void *val, void *old, int model) {
-#define LOCK_FREE_ACTION(type) \
- *(type*)old = __c11_atomic_exchange((_Atomic(type)*)ptr, *(type*)val,\
- model);\
- return;
- LOCK_FREE_CASES();
-#undef LOCK_FREE_ACTION
- Lock *l = lock_for_pointer(ptr);
- lock(l);
- memcpy(old, ptr, size);
- memcpy(ptr, val, size);
- unlock(l);
-}
-
-////////////////////////////////////////////////////////////////////////////////
-// Where the size is known at compile time, the compiler may emit calls to
-// specialised versions of the above functions.
-////////////////////////////////////////////////////////////////////////////////
-#define OPTIMISED_CASES\
- OPTIMISED_CASE(1, IS_LOCK_FREE_1, uint8_t)\
- OPTIMISED_CASE(2, IS_LOCK_FREE_2, uint16_t)\
- OPTIMISED_CASE(4, IS_LOCK_FREE_4, uint32_t)\
- OPTIMISED_CASE(8, IS_LOCK_FREE_8, uint64_t)\
- /* FIXME: __uint128_t isn't available on 32 bit platforms.
- OPTIMISED_CASE(16, IS_LOCK_FREE_16, __uint128_t)*/\
-
-#define OPTIMISED_CASE(n, lockfree, type)\
-type __atomic_load_##n(type *src, int model) {\
- if (lockfree)\
- return __c11_atomic_load((_Atomic(type)*)src, model);\
- Lock *l = lock_for_pointer(src);\
- lock(l);\
- type val = *src;\
- unlock(l);\
- return val;\
-}
-OPTIMISED_CASES
-#undef OPTIMISED_CASE
-
-#define OPTIMISED_CASE(n, lockfree, type)\
-void __atomic_store_##n(type *dest, type val, int model) {\
- if (lockfree) {\
- __c11_atomic_store((_Atomic(type)*)dest, val, model);\
- return;\
- }\
- Lock *l = lock_for_pointer(dest);\
- lock(l);\
- *dest = val;\
- unlock(l);\
- return;\
-}
-OPTIMISED_CASES
-#undef OPTIMISED_CASE
-
-#define OPTIMISED_CASE(n, lockfree, type)\
-type __atomic_exchange_##n(type *dest, type val, int model) {\
- if (lockfree)\
- return __c11_atomic_exchange((_Atomic(type)*)dest, val, model);\
- Lock *l = lock_for_pointer(dest);\
- lock(l);\
- type tmp = *dest;\
- *dest = val;\
- unlock(l);\
- return tmp;\
-}
-OPTIMISED_CASES
-#undef OPTIMISED_CASE
-
-#define OPTIMISED_CASE(n, lockfree, type)\
-int __atomic_compare_exchange_##n(type *ptr, type *expected, type desired,\
- int success, int failure) {\
- if (lockfree)\
- return __c11_atomic_compare_exchange_strong((_Atomic(type)*)ptr, expected, desired,\
- success, failure);\
- Lock *l = lock_for_pointer(ptr);\
- lock(l);\
- if (*ptr == *expected) {\
- *ptr = desired;\
- unlock(l);\
- return 1;\
- }\
- *expected = *ptr;\
- unlock(l);\
- return 0;\
-}
-OPTIMISED_CASES
-#undef OPTIMISED_CASE
-
-////////////////////////////////////////////////////////////////////////////////
-// Atomic read-modify-write operations for integers of various sizes.
-////////////////////////////////////////////////////////////////////////////////
-#define ATOMIC_RMW(n, lockfree, type, opname, op) \
-type __atomic_fetch_##opname##_##n(type *ptr, type val, int model) {\
- if (lockfree) \
- return __c11_atomic_fetch_##opname((_Atomic(type)*)ptr, val, model);\
- Lock *l = lock_for_pointer(ptr);\
- lock(l);\
- type tmp = *ptr;\
- *ptr = tmp op val;\
- unlock(l);\
- return tmp;\
-}
-
-#define OPTIMISED_CASE(n, lockfree, type) ATOMIC_RMW(n, lockfree, type, add, +)
-OPTIMISED_CASES
-#undef OPTIMISED_CASE
-#define OPTIMISED_CASE(n, lockfree, type) ATOMIC_RMW(n, lockfree, type, sub, -)
-OPTIMISED_CASES
-#undef OPTIMISED_CASE
-#define OPTIMISED_CASE(n, lockfree, type) ATOMIC_RMW(n, lockfree, type, and, &)
-OPTIMISED_CASES
-#undef OPTIMISED_CASE
-#define OPTIMISED_CASE(n, lockfree, type) ATOMIC_RMW(n, lockfree, type, or, |)
-OPTIMISED_CASES
-#undef OPTIMISED_CASE
-#define OPTIMISED_CASE(n, lockfree, type) ATOMIC_RMW(n, lockfree, type, xor, ^)
-OPTIMISED_CASES
-#undef OPTIMISED_CASE
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ *===----------------------------------------------------------------------===
+ *
+ * atomic.c defines a set of functions for performing atomic accesses on
+ * arbitrary-sized memory locations. This design uses locks that should
+ * be fast in the uncontended case, for two reasons:
+ *
+ * 1) This code must work with C programs that do not link to anything
+ * (including pthreads) and so it should not depend on any pthread
+ * functions.
+ * 2) Atomic operations, rather than explicit mutexes, are most commonly used
+ * on code where contended operations are rate.
+ *
+ * To avoid needing a per-object lock, this code allocates an array of
+ * locks and hashes the object pointers to find the one that it should use.
+ * For operations that must be atomic on two locations, the lower lock is
+ * always acquired first, to avoid deadlock.
+ *
+ *===----------------------------------------------------------------------===
+ */
+
+#include <stdint.h>
+#include <string.h>
+
+#include "assembly.h"
+
+// Clang objects if you redefine a builtin. This little hack allows us to
+// define a function with the same name as an intrinsic.
+#pragma redefine_extname __atomic_load_c SYMBOL_NAME(__atomic_load)
+#pragma redefine_extname __atomic_store_c SYMBOL_NAME(__atomic_store)
+#pragma redefine_extname __atomic_exchange_c SYMBOL_NAME(__atomic_exchange)
+#pragma redefine_extname __atomic_compare_exchange_c SYMBOL_NAME(__atomic_compare_exchange)
+
+/// Number of locks. This allocates one page on 32-bit platforms, two on
+/// 64-bit. This can be specified externally if a different trade between
+/// memory usage and contention probability is required for a given platform.
+#ifndef SPINLOCK_COUNT
+#define SPINLOCK_COUNT (1<<10)
+#endif
+static const long SPINLOCK_MASK = SPINLOCK_COUNT - 1;
+
+////////////////////////////////////////////////////////////////////////////////
+// Platform-specific lock implementation. Falls back to spinlocks if none is
+// defined. Each platform should define the Lock type, and corresponding
+// lock() and unlock() functions.
+////////////////////////////////////////////////////////////////////////////////
+#ifdef __FreeBSD__
+#include <errno.h>
+#include <sys/types.h>
+#include <machine/atomic.h>
+#include <sys/umtx.h>
+typedef struct _usem Lock;
+__inline static void unlock(Lock *l) {
+ __c11_atomic_store((_Atomic(uint32_t)*)&l->_count, 1, __ATOMIC_RELEASE);
+ __c11_atomic_thread_fence(__ATOMIC_SEQ_CST);
+ if (l->_has_waiters)
+ _umtx_op(l, UMTX_OP_SEM_WAKE, 1, 0, 0);
+}
+__inline static void lock(Lock *l) {
+ uint32_t old = 1;
+ while (!__c11_atomic_compare_exchange_weak((_Atomic(uint32_t)*)&l->_count, &old,
+ 0, __ATOMIC_ACQUIRE, __ATOMIC_RELAXED)) {
+ _umtx_op(l, UMTX_OP_SEM_WAIT, 0, 0, 0);
+ old = 1;
+ }
+}
+/// locks for atomic operations
+static Lock locks[SPINLOCK_COUNT] = { [0 ... SPINLOCK_COUNT-1] = {0,1,0} };
+
+#elif defined(__APPLE__)
+#include <libkern/OSAtomic.h>
+typedef OSSpinLock Lock;
+__inline static void unlock(Lock *l) {
+ OSSpinLockUnlock(l);
+}
+/// Locks a lock. In the current implementation, this is potentially
+/// unbounded in the contended case.
+__inline static void lock(Lock *l) {
+ OSSpinLockLock(l);
+}
+static Lock locks[SPINLOCK_COUNT]; // initialized to OS_SPINLOCK_INIT which is 0
+
+#else
+typedef _Atomic(uintptr_t) Lock;
+/// Unlock a lock. This is a release operation.
+__inline static void unlock(Lock *l) {
+ __c11_atomic_store(l, 0, __ATOMIC_RELEASE);
+}
+/// Locks a lock. In the current implementation, this is potentially
+/// unbounded in the contended case.
+__inline static void lock(Lock *l) {
+ uintptr_t old = 0;
+ while (!__c11_atomic_compare_exchange_weak(l, &old, 1, __ATOMIC_ACQUIRE,
+ __ATOMIC_RELAXED))
+ old = 0;
+}
+/// locks for atomic operations
+static Lock locks[SPINLOCK_COUNT];
+#endif
+
+
+/// Returns a lock to use for a given pointer.
+static __inline Lock *lock_for_pointer(void *ptr) {
+ intptr_t hash = (intptr_t)ptr;
+ // Disregard the lowest 4 bits. We want all values that may be part of the
+ // same memory operation to hash to the same value and therefore use the same
+ // lock.
+ hash >>= 4;
+ // Use the next bits as the basis for the hash
+ intptr_t low = hash & SPINLOCK_MASK;
+ // Now use the high(er) set of bits to perturb the hash, so that we don't
+ // get collisions from atomic fields in a single object
+ hash >>= 16;
+ hash ^= low;
+ // Return a pointer to the word to use
+ return locks + (hash & SPINLOCK_MASK);
+}
+
+/// Macros for determining whether a size is lock free. Clang can not yet
+/// codegen __atomic_is_lock_free(16), so for now we assume 16-byte values are
+/// not lock free.
+#define IS_LOCK_FREE_1 __c11_atomic_is_lock_free(1)
+#define IS_LOCK_FREE_2 __c11_atomic_is_lock_free(2)
+#define IS_LOCK_FREE_4 __c11_atomic_is_lock_free(4)
+#define IS_LOCK_FREE_8 __c11_atomic_is_lock_free(8)
+#define IS_LOCK_FREE_16 0
+
+/// Macro that calls the compiler-generated lock-free versions of functions
+/// when they exist.
+#define LOCK_FREE_CASES() \
+ do {\
+ switch (size) {\
+ case 2:\
+ if (IS_LOCK_FREE_2) {\
+ LOCK_FREE_ACTION(uint16_t);\
+ }\
+ case 4:\
+ if (IS_LOCK_FREE_4) {\
+ LOCK_FREE_ACTION(uint32_t);\
+ }\
+ case 8:\
+ if (IS_LOCK_FREE_8) {\
+ LOCK_FREE_ACTION(uint64_t);\
+ }\
+ case 16:\
+ if (IS_LOCK_FREE_16) {\
+ /* FIXME: __uint128_t isn't available on 32 bit platforms.
+ LOCK_FREE_ACTION(__uint128_t);*/\
+ }\
+ }\
+ } while (0)
+
+
+/// An atomic load operation. This is atomic with respect to the source
+/// pointer only.
+void __atomic_load_c(int size, void *src, void *dest, int model) {
+#define LOCK_FREE_ACTION(type) \
+ *((type*)dest) = __c11_atomic_load((_Atomic(type)*)src, model);\
+ return;
+ LOCK_FREE_CASES();
+#undef LOCK_FREE_ACTION
+ Lock *l = lock_for_pointer(src);
+ lock(l);
+ memcpy(dest, src, size);
+ unlock(l);
+}
+
+/// An atomic store operation. This is atomic with respect to the destination
+/// pointer only.
+void __atomic_store_c(int size, void *dest, void *src, int model) {
+#define LOCK_FREE_ACTION(type) \
+ __c11_atomic_store((_Atomic(type)*)dest, *(type*)dest, model);\
+ return;
+ LOCK_FREE_CASES();
+#undef LOCK_FREE_ACTION
+ Lock *l = lock_for_pointer(dest);
+ lock(l);
+ memcpy(dest, src, size);
+ unlock(l);
+}
+
+/// Atomic compare and exchange operation. If the value at *ptr is identical
+/// to the value at *expected, then this copies value at *desired to *ptr. If
+/// they are not, then this stores the current value from *ptr in *expected.
+///
+/// This function returns 1 if the exchange takes place or 0 if it fails.
+int __atomic_compare_exchange_c(int size, void *ptr, void *expected,
+ void *desired, int success, int failure) {
+#define LOCK_FREE_ACTION(type) \
+ return __c11_atomic_compare_exchange_strong((_Atomic(type)*)ptr, (type*)expected,\
+ *(type*)desired, success, failure)
+ LOCK_FREE_CASES();
+#undef LOCK_FREE_ACTION
+ Lock *l = lock_for_pointer(ptr);
+ lock(l);
+ if (memcmp(ptr, expected, size) == 0) {
+ memcpy(ptr, desired, size);
+ unlock(l);
+ return 1;
+ }
+ memcpy(expected, ptr, size);
+ unlock(l);
+ return 0;
+}
+
+/// Performs an atomic exchange operation between two pointers. This is atomic
+/// with respect to the target address.
+void __atomic_exchange_c(int size, void *ptr, void *val, void *old, int model) {
+#define LOCK_FREE_ACTION(type) \
+ *(type*)old = __c11_atomic_exchange((_Atomic(type)*)ptr, *(type*)val,\
+ model);\
+ return;
+ LOCK_FREE_CASES();
+#undef LOCK_FREE_ACTION
+ Lock *l = lock_for_pointer(ptr);
+ lock(l);
+ memcpy(old, ptr, size);
+ memcpy(ptr, val, size);
+ unlock(l);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Where the size is known at compile time, the compiler may emit calls to
+// specialised versions of the above functions.
+////////////////////////////////////////////////////////////////////////////////
+#define OPTIMISED_CASES\
+ OPTIMISED_CASE(1, IS_LOCK_FREE_1, uint8_t)\
+ OPTIMISED_CASE(2, IS_LOCK_FREE_2, uint16_t)\
+ OPTIMISED_CASE(4, IS_LOCK_FREE_4, uint32_t)\
+ OPTIMISED_CASE(8, IS_LOCK_FREE_8, uint64_t)\
+ /* FIXME: __uint128_t isn't available on 32 bit platforms.
+ OPTIMISED_CASE(16, IS_LOCK_FREE_16, __uint128_t)*/\
+
+#define OPTIMISED_CASE(n, lockfree, type)\
+type __atomic_load_##n(type *src, int model) {\
+ if (lockfree)\
+ return __c11_atomic_load((_Atomic(type)*)src, model);\
+ Lock *l = lock_for_pointer(src);\
+ lock(l);\
+ type val = *src;\
+ unlock(l);\
+ return val;\
+}
+OPTIMISED_CASES
+#undef OPTIMISED_CASE
+
+#define OPTIMISED_CASE(n, lockfree, type)\
+void __atomic_store_##n(type *dest, type val, int model) {\
+ if (lockfree) {\
+ __c11_atomic_store((_Atomic(type)*)dest, val, model);\
+ return;\
+ }\
+ Lock *l = lock_for_pointer(dest);\
+ lock(l);\
+ *dest = val;\
+ unlock(l);\
+ return;\
+}
+OPTIMISED_CASES
+#undef OPTIMISED_CASE
+
+#define OPTIMISED_CASE(n, lockfree, type)\
+type __atomic_exchange_##n(type *dest, type val, int model) {\
+ if (lockfree)\
+ return __c11_atomic_exchange((_Atomic(type)*)dest, val, model);\
+ Lock *l = lock_for_pointer(dest);\
+ lock(l);\
+ type tmp = *dest;\
+ *dest = val;\
+ unlock(l);\
+ return tmp;\
+}
+OPTIMISED_CASES
+#undef OPTIMISED_CASE
+
+#define OPTIMISED_CASE(n, lockfree, type)\
+int __atomic_compare_exchange_##n(type *ptr, type *expected, type desired,\
+ int success, int failure) {\
+ if (lockfree)\
+ return __c11_atomic_compare_exchange_strong((_Atomic(type)*)ptr, expected, desired,\
+ success, failure);\
+ Lock *l = lock_for_pointer(ptr);\
+ lock(l);\
+ if (*ptr == *expected) {\
+ *ptr = desired;\
+ unlock(l);\
+ return 1;\
+ }\
+ *expected = *ptr;\
+ unlock(l);\
+ return 0;\
+}
+OPTIMISED_CASES
+#undef OPTIMISED_CASE
+
+////////////////////////////////////////////////////////////////////////////////
+// Atomic read-modify-write operations for integers of various sizes.
+////////////////////////////////////////////////////////////////////////////////
+#define ATOMIC_RMW(n, lockfree, type, opname, op) \
+type __atomic_fetch_##opname##_##n(type *ptr, type val, int model) {\
+ if (lockfree) \
+ return __c11_atomic_fetch_##opname((_Atomic(type)*)ptr, val, model);\
+ Lock *l = lock_for_pointer(ptr);\
+ lock(l);\
+ type tmp = *ptr;\
+ *ptr = tmp op val;\
+ unlock(l);\
+ return tmp;\
+}
+
+#define OPTIMISED_CASE(n, lockfree, type) ATOMIC_RMW(n, lockfree, type, add, +)
+OPTIMISED_CASES
+#undef OPTIMISED_CASE
+#define OPTIMISED_CASE(n, lockfree, type) ATOMIC_RMW(n, lockfree, type, sub, -)
+OPTIMISED_CASES
+#undef OPTIMISED_CASE
+#define OPTIMISED_CASE(n, lockfree, type) ATOMIC_RMW(n, lockfree, type, and, &)
+OPTIMISED_CASES
+#undef OPTIMISED_CASE
+#define OPTIMISED_CASE(n, lockfree, type) ATOMIC_RMW(n, lockfree, type, or, |)
+OPTIMISED_CASES
+#undef OPTIMISED_CASE
+#define OPTIMISED_CASE(n, lockfree, type) ATOMIC_RMW(n, lockfree, type, xor, ^)
+OPTIMISED_CASES
+#undef OPTIMISED_CASE