aboutsummaryrefslogtreecommitdiff
path: root/src/mesa/util/u_atomic.h
diff options
context:
space:
mode:
Diffstat (limited to 'src/mesa/util/u_atomic.h')
-rw-r--r--src/mesa/util/u_atomic.h272
1 files changed, 272 insertions, 0 deletions
diff --git a/src/mesa/util/u_atomic.h b/src/mesa/util/u_atomic.h
new file mode 100644
index 00000000..0bd6a4aa
--- /dev/null
+++ b/src/mesa/util/u_atomic.h
@@ -0,0 +1,272 @@
+/**
+ * Many similar implementations exist. See for example libwsbm
+ * or the linux kernel include/atomic.h
+ *
+ * No copyright claimed on this file.
+ *
+ */
+
+#include "no_extern_c.h"
+
+#ifndef U_ATOMIC_H
+#define U_ATOMIC_H
+
+#include <stdbool.h>
+#include <stdint.h>
+
+/* Favor OS-provided implementations.
+ *
+ * Where no OS-provided implementation is available, fall back to
+ * locally coded assembly, compiler intrinsic or ultimately a
+ * mutex-based implementation.
+ */
+#if defined(__sun)
+#define PIPE_ATOMIC_OS_SOLARIS
+#elif defined(_MSC_VER)
+#define PIPE_ATOMIC_MSVC_INTRINSIC
+#elif defined(__GNUC__)
+#define PIPE_ATOMIC_GCC_INTRINSIC
+#else
+#error "Unsupported platform"
+#endif
+
+
+/* Implementation using GCC-provided synchronization intrinsics
+ */
+#if defined(PIPE_ATOMIC_GCC_INTRINSIC)
+
+#define PIPE_ATOMIC "GCC Sync Intrinsics"
+
+#if defined(USE_GCC_ATOMIC_BUILTINS)
+
+/* The builtins with explicit memory model are available since GCC 4.7. */
+#define p_atomic_set(_v, _i) __atomic_store_n((_v), (_i), __ATOMIC_RELEASE)
+#define p_atomic_read(_v) __atomic_load_n((_v), __ATOMIC_ACQUIRE)
+#define p_atomic_read_relaxed(_v) __atomic_load_n((_v), __ATOMIC_RELAXED)
+#define p_atomic_dec_zero(v) (__atomic_sub_fetch((v), 1, __ATOMIC_ACQ_REL) == 0)
+#define p_atomic_inc(v) (void) __atomic_add_fetch((v), 1, __ATOMIC_ACQ_REL)
+#define p_atomic_dec(v) (void) __atomic_sub_fetch((v), 1, __ATOMIC_ACQ_REL)
+#define p_atomic_add(v, i) (void) __atomic_add_fetch((v), (i), __ATOMIC_ACQ_REL)
+#define p_atomic_inc_return(v) __atomic_add_fetch((v), 1, __ATOMIC_ACQ_REL)
+#define p_atomic_dec_return(v) __atomic_sub_fetch((v), 1, __ATOMIC_ACQ_REL)
+#define p_atomic_add_return(v, i) __atomic_add_fetch((v), (i), __ATOMIC_ACQ_REL)
+#define p_atomic_xchg(v, i) __atomic_exchange_n((v), (i), __ATOMIC_ACQ_REL)
+#define PIPE_NATIVE_ATOMIC_XCHG
+
+#else
+
+#define p_atomic_set(_v, _i) (*(_v) = (_i))
+#define p_atomic_read(_v) (*(_v))
+#define p_atomic_read_relaxed(_v) (*(_v))
+#define p_atomic_dec_zero(v) (__sync_sub_and_fetch((v), 1) == 0)
+#define p_atomic_inc(v) (void) __sync_add_and_fetch((v), 1)
+#define p_atomic_dec(v) (void) __sync_sub_and_fetch((v), 1)
+#define p_atomic_add(v, i) (void) __sync_add_and_fetch((v), (i))
+#define p_atomic_inc_return(v) __sync_add_and_fetch((v), 1)
+#define p_atomic_dec_return(v) __sync_sub_and_fetch((v), 1)
+#define p_atomic_add_return(v, i) __sync_add_and_fetch((v), (i))
+
+#endif
+
+/* There is no __atomic_* compare and exchange that returns the current value.
+ * Also, GCC 5.4 seems unable to optimize a compound statement expression that
+ * uses an additional stack variable with __atomic_compare_exchange[_n].
+ */
+#define p_atomic_cmpxchg(v, old, _new) \
+ __sync_val_compare_and_swap((v), (old), (_new))
+
+#endif
+
+
+
+/* Unlocked version for single threaded environments, such as some
+ * windows kernel modules.
+ */
+#if defined(PIPE_ATOMIC_OS_UNLOCKED)
+
+#define PIPE_ATOMIC "Unlocked"
+
+#define p_atomic_set(_v, _i) (*(_v) = (_i))
+#define p_atomic_read(_v) (*(_v))
+#define p_atomic_read_relaxed(_v) (*(_v))
+#define p_atomic_dec_zero(_v) (p_atomic_dec_return(_v) == 0)
+#define p_atomic_inc(_v) ((void) p_atomic_inc_return(_v))
+#define p_atomic_dec(_v) ((void) p_atomic_dec_return(_v))
+#define p_atomic_add(_v, _i) ((void) p_atomic_add_return((_v), (_i)))
+#define p_atomic_inc_return(_v) (++(*(_v)))
+#define p_atomic_dec_return(_v) (--(*(_v)))
+#define p_atomic_add_return(_v, _i) (*(_v) = *(_v) + (_i))
+#define p_atomic_cmpxchg(_v, _old, _new) (*(_v) == (_old) ? (*(_v) = (_new), (_old)) : *(_v))
+
+#endif
+
+
+#if defined(PIPE_ATOMIC_MSVC_INTRINSIC)
+
+#define PIPE_ATOMIC "MSVC Intrinsics"
+
+/* We use the Windows header's Interlocked*64 functions instead of the
+ * _Interlocked*64 intrinsics wherever we can, as support for the latter varies
+ * with target CPU, whereas Windows headers take care of all portability
+ * issues: using intrinsics where available, falling back to library
+ * implementations where not.
+ */
+#ifndef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN 1
+#endif
+#include <windows.h>
+#include <intrin.h>
+#include <assert.h>
+
+/* MSVC supports decltype keyword, but it's only supported on C++ and doesn't
+ * quite work here; and if a C++-only solution is worthwhile, then it would be
+ * better to use templates / function overloading, instead of decltype magic.
+ * Therefore, we rely on implicit casting to LONGLONG for the functions that return
+ */
+
+#define p_atomic_set(_v, _i) (*(_v) = (_i))
+#define p_atomic_read(_v) (*(_v))
+#define p_atomic_read_relaxed(_v) (*(_v))
+
+#define p_atomic_dec_zero(_v) \
+ (p_atomic_dec_return(_v) == 0)
+
+#define p_atomic_inc(_v) \
+ ((void) p_atomic_inc_return(_v))
+
+#define p_atomic_inc_return(_v) (\
+ sizeof *(_v) == sizeof(short) ? _InterlockedIncrement16((short *) (_v)) : \
+ sizeof *(_v) == sizeof(long) ? _InterlockedIncrement ((long *) (_v)) : \
+ sizeof *(_v) == sizeof(__int64) ? InterlockedIncrement64 ((__int64 *)(_v)) : \
+ (assert(!"should not get here"), 0))
+
+#define p_atomic_dec(_v) \
+ ((void) p_atomic_dec_return(_v))
+
+#define p_atomic_dec_return(_v) (\
+ sizeof *(_v) == sizeof(short) ? _InterlockedDecrement16((short *) (_v)) : \
+ sizeof *(_v) == sizeof(long) ? _InterlockedDecrement ((long *) (_v)) : \
+ sizeof *(_v) == sizeof(__int64) ? InterlockedDecrement64 ((__int64 *)(_v)) : \
+ (assert(!"should not get here"), 0))
+
+#define p_atomic_add(_v, _i) \
+ ((void) p_atomic_add_return((_v), (_i)))
+
+#define p_atomic_add_return(_v, _i) (\
+ sizeof *(_v) == sizeof(char) ? _InterlockedExchangeAdd8 ((char *) (_v), (_i)) : \
+ sizeof *(_v) == sizeof(short) ? _InterlockedExchangeAdd16((short *) (_v), (_i)) : \
+ sizeof *(_v) == sizeof(long) ? _InterlockedExchangeAdd ((long *) (_v), (_i)) : \
+ sizeof *(_v) == sizeof(__int64) ? InterlockedExchangeAdd64((__int64 *)(_v), (_i)) : \
+ (assert(!"should not get here"), 0))
+
+#define p_atomic_cmpxchg(_v, _old, _new) (\
+ sizeof *(_v) == sizeof(char) ? _InterlockedCompareExchange8 ((char *) (_v), (char) (_new), (char) (_old)) : \
+ sizeof *(_v) == sizeof(short) ? _InterlockedCompareExchange16((short *) (_v), (short) (_new), (short) (_old)) : \
+ sizeof *(_v) == sizeof(long) ? _InterlockedCompareExchange ((long *) (_v), (long) (_new), (long) (_old)) : \
+ sizeof *(_v) == sizeof(__int64) ? InterlockedCompareExchange64 ((__int64 *)(_v), (__int64)(_new), (__int64)(_old)) : \
+ (assert(!"should not get here"), 0))
+
+#endif
+
+#if defined(PIPE_ATOMIC_OS_SOLARIS)
+
+#define PIPE_ATOMIC "Solaris OS atomic functions"
+
+#include <atomic.h>
+#include <assert.h>
+
+#define p_atomic_set(_v, _i) (*(_v) = (_i))
+#define p_atomic_read(_v) (*(_v))
+
+#define p_atomic_dec_zero(v) (\
+ sizeof(*v) == sizeof(uint8_t) ? atomic_dec_8_nv ((uint8_t *)(v)) == 0 : \
+ sizeof(*v) == sizeof(uint16_t) ? atomic_dec_16_nv((uint16_t *)(v)) == 0 : \
+ sizeof(*v) == sizeof(uint32_t) ? atomic_dec_32_nv((uint32_t *)(v)) == 0 : \
+ sizeof(*v) == sizeof(uint64_t) ? atomic_dec_64_nv((uint64_t *)(v)) == 0 : \
+ (assert(!"should not get here"), 0))
+
+#define p_atomic_inc(v) (void) (\
+ sizeof(*v) == sizeof(uint8_t) ? atomic_inc_8 ((uint8_t *)(v)) : \
+ sizeof(*v) == sizeof(uint16_t) ? atomic_inc_16((uint16_t *)(v)) : \
+ sizeof(*v) == sizeof(uint32_t) ? atomic_inc_32((uint32_t *)(v)) : \
+ sizeof(*v) == sizeof(uint64_t) ? atomic_inc_64((uint64_t *)(v)) : \
+ (assert(!"should not get here"), 0))
+
+#define p_atomic_inc_return(v) (__typeof(*v))( \
+ sizeof(*v) == sizeof(uint8_t) ? atomic_inc_8_nv ((uint8_t *)(v)) : \
+ sizeof(*v) == sizeof(uint16_t) ? atomic_inc_16_nv((uint16_t *)(v)) : \
+ sizeof(*v) == sizeof(uint32_t) ? atomic_inc_32_nv((uint32_t *)(v)) : \
+ sizeof(*v) == sizeof(uint64_t) ? atomic_inc_64_nv((uint64_t *)(v)) : \
+ (assert(!"should not get here"), 0))
+
+#define p_atomic_dec(v) (void) ( \
+ sizeof(*v) == sizeof(uint8_t) ? atomic_dec_8 ((uint8_t *)(v)) : \
+ sizeof(*v) == sizeof(uint16_t) ? atomic_dec_16((uint16_t *)(v)) : \
+ sizeof(*v) == sizeof(uint32_t) ? atomic_dec_32((uint32_t *)(v)) : \
+ sizeof(*v) == sizeof(uint64_t) ? atomic_dec_64((uint64_t *)(v)) : \
+ (assert(!"should not get here"), 0))
+
+#define p_atomic_dec_return(v) (__typeof(*v))( \
+ sizeof(*v) == sizeof(uint8_t) ? atomic_dec_8_nv ((uint8_t *)(v)) : \
+ sizeof(*v) == sizeof(uint16_t) ? atomic_dec_16_nv((uint16_t *)(v)) : \
+ sizeof(*v) == sizeof(uint32_t) ? atomic_dec_32_nv((uint32_t *)(v)) : \
+ sizeof(*v) == sizeof(uint64_t) ? atomic_dec_64_nv((uint64_t *)(v)) : \
+ (assert(!"should not get here"), 0))
+
+#define p_atomic_add(v, i) (void) ( \
+ sizeof(*v) == sizeof(uint8_t) ? atomic_add_8 ((uint8_t *)(v), (i)) : \
+ sizeof(*v) == sizeof(uint16_t) ? atomic_add_16((uint16_t *)(v), (i)) : \
+ sizeof(*v) == sizeof(uint32_t) ? atomic_add_32((uint32_t *)(v), (i)) : \
+ sizeof(*v) == sizeof(uint64_t) ? atomic_add_64((uint64_t *)(v), (i)) : \
+ (assert(!"should not get here"), 0))
+
+#define p_atomic_add_return(v, i) (__typeof(*v)) ( \
+ sizeof(*v) == sizeof(uint8_t) ? atomic_add_8_nv ((uint8_t *)(v), (i)) : \
+ sizeof(*v) == sizeof(uint16_t) ? atomic_add_16_nv((uint16_t *)(v), (i)) : \
+ sizeof(*v) == sizeof(uint32_t) ? atomic_add_32_nv((uint32_t *)(v), (i)) : \
+ sizeof(*v) == sizeof(uint64_t) ? atomic_add_64_nv((uint64_t *)(v), (i)) : \
+ (assert(!"should not get here"), 0))
+
+#define p_atomic_cmpxchg(v, old, _new) (__typeof(*v))( \
+ sizeof(*v) == sizeof(uint8_t) ? atomic_cas_8 ((uint8_t *)(v), (uint8_t )(old), (uint8_t )(_new)) : \
+ sizeof(*v) == sizeof(uint16_t) ? atomic_cas_16((uint16_t *)(v), (uint16_t)(old), (uint16_t)(_new)) : \
+ sizeof(*v) == sizeof(uint32_t) ? atomic_cas_32((uint32_t *)(v), (uint32_t)(old), (uint32_t)(_new)) : \
+ sizeof(*v) == sizeof(uint64_t) ? atomic_cas_64((uint64_t *)(v), (uint64_t)(old), (uint64_t)(_new)) : \
+ (assert(!"should not get here"), 0))
+
+#endif
+
+#ifndef PIPE_ATOMIC
+#error "No pipe_atomic implementation selected"
+#endif
+
+#ifndef PIPE_NATIVE_ATOMIC_XCHG
+static inline uint32_t p_atomic_xchg_32(uint32_t *v, uint32_t i)
+{
+ uint32_t actual = p_atomic_read(v);
+ uint32_t expected;
+ do {
+ expected = actual;
+ actual = p_atomic_cmpxchg(v, expected, i);
+ } while (expected != actual);
+ return actual;
+}
+
+static inline uint64_t p_atomic_xchg_64(uint64_t *v, uint64_t i)
+{
+ uint64_t actual = p_atomic_read(v);
+ uint64_t expected;
+ do {
+ expected = actual;
+ actual = p_atomic_cmpxchg(v, expected, i);
+ } while (expected != actual);
+ return actual;
+}
+
+#define p_atomic_xchg(v, i) (__typeof(*(v)))( \
+ sizeof(*(v)) == sizeof(uint32_t) ? p_atomic_xchg_32((uint32_t *)(v), (uint32_t)(i)) : \
+ sizeof(*(v)) == sizeof(uint64_t) ? p_atomic_xchg_64((uint64_t *)(v), (uint64_t)(i)) : \
+ (assert(!"should not get here"), 0))
+#endif
+
+#endif /* U_ATOMIC_H */
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-10 19:51:43 +0000