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authorJosé Fonseca <[email protected]>2010-02-03 18:54:13 +0000
committerJosé Fonseca <[email protected]>2010-02-03 18:54:13 +0000
commit45dac0d82a5a69166e86dce77c2550f7512c541e (patch)
tree41a10f422174ef9543db2396057f052c056eb396 /src/gallium/auxiliary/util/u_atomic.h
parentf8d824e09a54871df899f368ebaadc9a4e5b62ff (diff)
parent976afaf98f4b1ce32003dd014cbb3c09063bcb68 (diff)
Merge branch 'gallium-embedded'
Diffstat (limited to 'src/gallium/auxiliary/util/u_atomic.h')
-rw-r--r--src/gallium/auxiliary/util/u_atomic.h247
1 files changed, 247 insertions, 0 deletions
diff --git a/src/gallium/auxiliary/util/u_atomic.h b/src/gallium/auxiliary/util/u_atomic.h
new file mode 100644
index 00000000000..1c042c3ede9
--- /dev/null
+++ b/src/gallium/auxiliary/util/u_atomic.h
@@ -0,0 +1,247 @@
+/**
+ * Many similar implementations exist. See for example libwsbm
+ * or the linux kernel include/atomic.h
+ *
+ * No copyright claimed on this file.
+ *
+ */
+
+#ifndef U_ATOMIC_H
+#define U_ATOMIC_H
+
+#include "pipe/p_compiler.h"
+#include "pipe/p_defines.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/* 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(PIPE_SUBSYSTEM_WINDOWS_DISPLAY) || \
+ defined(PIPE_SUBSYSTEM_WINDOWS_MINIPORT))
+#define PIPE_ATOMIC_OS_UNLOCKED
+#elif defined(PIPE_CC_MSVC)
+#define PIPE_ATOMIC_MSVC_INTRINSIC
+#elif (defined(PIPE_CC_MSVC) && defined(PIPE_ARCH_X86))
+#define PIPE_ATOMIC_ASM_MSVC_X86
+#elif (defined(PIPE_CC_GCC) && defined(PIPE_ARCH_X86))
+#define PIPE_ATOMIC_ASM_GCC_X86
+#elif defined(PIPE_CC_GCC)
+#define PIPE_ATOMIC_GCC_INTRINSIC
+#else
+#error "Unsupported platform"
+#endif
+
+
+
+#if defined(PIPE_ATOMIC_ASM_GCC_X86)
+
+#define PIPE_ATOMIC "GCC x86 assembly"
+
+#define p_atomic_set(_v, _i) (*(_v) = (_i))
+#define p_atomic_read(_v) (*(_v))
+
+
+static INLINE boolean
+p_atomic_dec_zero(int32_t *v)
+{
+ unsigned char c;
+
+ __asm__ __volatile__("lock; decl %0; sete %1":"+m"(*v), "=qm"(c)
+ ::"memory");
+
+ return c != 0;
+}
+
+static INLINE void
+p_atomic_inc(int32_t *v)
+{
+ __asm__ __volatile__("lock; incl %0":"+m"(*v));
+}
+
+static INLINE void
+p_atomic_dec(int32_t *v)
+{
+ __asm__ __volatile__("lock; decl %0":"+m"(*v));
+}
+
+static INLINE int32_t
+p_atomic_cmpxchg(int32_t *v, int32_t old, int32_t _new)
+{
+ return __sync_val_compare_and_swap(v, old, _new);
+}
+#endif
+
+
+
+/* Implementation using GCC-provided synchronization intrinsics
+ */
+#if defined(PIPE_ATOMIC_GCC_INTRINSIC)
+
+#define PIPE_ATOMIC "GCC Sync Intrinsics"
+
+#define p_atomic_set(_v, _i) (*(_v) = (_i))
+#define p_atomic_read(_v) (*(_v))
+
+
+static INLINE boolean
+p_atomic_dec_zero(int32_t *v)
+{
+ return (__sync_sub_and_fetch(v, 1) == 0);
+}
+
+static INLINE void
+p_atomic_inc(int32_t *v)
+{
+ (void) __sync_add_and_fetch(v, 1);
+}
+
+static INLINE void
+p_atomic_dec(int32_t *v)
+{
+ (void) __sync_sub_and_fetch(v, 1);
+}
+
+static INLINE int32_t
+p_atomic_cmpxchg(int32_t *v, int32_t old, int32_t _new)
+{
+ return __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_dec_zero(_v) ((boolean) --(*(_v)))
+#define p_atomic_inc(_v) ((void) (*(_v))++)
+#define p_atomic_dec(_v) ((void) (*(_v))--)
+#define p_atomic_cmpxchg(_v, old, _new) (*(_v) == old ? *(_v) = (_new) : *(_v))
+
+#endif
+
+
+/* Locally coded assembly for MSVC on x86:
+ */
+#if defined(PIPE_ATOMIC_ASM_MSVC_X86)
+
+#define PIPE_ATOMIC "MSVC x86 assembly"
+
+#define p_atomic_set(_v, _i) (*(_v) = (_i))
+#define p_atomic_read(_v) (*(_v))
+
+static INLINE boolean
+p_atomic_dec_zero(int32_t *v)
+{
+ unsigned char c;
+
+ __asm {
+ mov eax, [v]
+ lock dec dword ptr [eax]
+ sete byte ptr [c]
+ }
+
+ return c != 0;
+}
+
+static INLINE void
+p_atomic_inc(int32_t *v)
+{
+ __asm {
+ mov eax, [v]
+ lock inc dword ptr [eax]
+ }
+}
+
+static INLINE void
+p_atomic_dec(int32_t *v)
+{
+ __asm {
+ mov eax, [v]
+ lock dec dword ptr [eax]
+ }
+}
+
+static INLINE int32_t
+p_atomic_cmpxchg(int32_t *v, int32_t old, int32_t _new)
+{
+ int32_t orig;
+
+ __asm {
+ mov ecx, [v]
+ mov eax, [old]
+ mov edx, [_new]
+ lock cmpxchg [ecx], edx
+ mov [orig], eax
+ }
+
+ return orig;
+}
+#endif
+
+
+#if defined(PIPE_ATOMIC_MSVC_INTRINSIC)
+
+#define PIPE_ATOMIC "MSVC Intrinsics"
+
+#include <intrin.h>
+
+#pragma intrinsic(_InterlockedIncrement)
+#pragma intrinsic(_InterlockedDecrement)
+#pragma intrinsic(_InterlockedCompareExchange)
+
+#define p_atomic_set(_v, _i) (*(_v) = (_i))
+#define p_atomic_read(_v) (*(_v))
+
+static INLINE boolean
+p_atomic_dec_zero(int32_t *v)
+{
+ return _InterlockedDecrement(v) == 0;
+}
+
+static INLINE void
+p_atomic_inc(int32_t *v)
+{
+ _InterlockedIncrement(v);
+}
+
+static INLINE void
+p_atomic_dec(int32_t *v)
+{
+ _InterlockedDecrement(v);
+}
+
+static INLINE int32_t
+p_atomic_cmpxchg(int32_t *v, int32_t old, int32_t _new)
+{
+ return _InterlockedCompareExchange(v, _new, old);
+}
+
+#endif
+
+
+
+#ifndef PIPE_ATOMIC
+#error "No pipe_atomic implementation selected"
+#endif
+
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* U_ATOMIC_H */