1 files changed, 353 insertions, 0 deletions
diff --git a/src/gallium/include/pipe/p_atomic.h b/src/gallium/include/pipe/p_atomic.h
new file mode 100644
index 0000000000..0c3fbae428
--- /dev/null
+++ b/src/gallium/include/pipe/p_atomic.h
@@ -0,0 +1,353 @@
+/**
+ * Many similar implementations exist. See for example libwsbm
+ * or the linux kernel include/atomic.h
+ *
+ * No copyright claimed on this file.
+ *
+ */
+
+#ifndef P_ATOMIC_H
+#define P_ATOMIC_H
+
+#include "p_compiler.h"
+#include "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) && defined(PIPE_SUBSYSTEM_WINDOWS_USER))
+#define PIPE_ATOMIC_OS_MS_INTERLOCK
+#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
+#define PIPE_ATOMIC_MUTEX                       
+#endif
+
+
+
+#if defined(PIPE_ATOMIC_ASM_GCC_X86)
+
+#define PIPE_ATOMIC "GCC x86 assembly"
+
+struct pipe_atomic {
+   int32_t count;
+};
+
+#define p_atomic_set(_v, _i) ((_v)->count = (_i))
+#define p_atomic_read(_v) ((_v)->count)
+
+
+static INLINE boolean
+p_atomic_dec_zero(struct pipe_atomic *v)
+{
+   unsigned char c;
+
+   __asm__ __volatile__("lock; decl %0; sete %1":"+m"(v->count), "=qm"(c)
+			::"memory");
+
+   return c != 0;
+}
+
+static INLINE void
+p_atomic_inc(struct pipe_atomic *v)
+{
+   __asm__ __volatile__("lock; incl %0":"+m"(v->count));
+}
+
+static INLINE void
+p_atomic_dec(struct pipe_atomic *v)
+{
+   __asm__ __volatile__("lock; decl %0":"+m"(v->count));
+}
+
+static INLINE int32_t
+p_atomic_cmpxchg(struct pipe_atomic *v, int32_t old, int32_t _new)
+{
+   return __sync_val_compare_and_swap(&v->count, old, _new);
+}
+#endif
+
+
+
+/* Implementation using GCC-provided synchronization intrinsics
+ */
+#if defined(PIPE_ATOMIC_GCC_INTRINSIC)
+
+#define PIPE_ATOMIC "GCC Sync Intrinsics"
+
+struct pipe_atomic {
+   int32_t count;
+};
+
+#define p_atomic_set(_v, _i) ((_v)->count = (_i))
+#define p_atomic_read(_v) ((_v)->count)
+
+
+static INLINE boolean
+p_atomic_dec_zero(struct pipe_atomic *v)
+{
+   return (__sync_sub_and_fetch(&v->count, 1) == 0);
+}
+
+static INLINE void
+p_atomic_inc(struct pipe_atomic *v)
+{
+   (void) __sync_add_and_fetch(&v->count, 1);
+}
+
+static INLINE void
+p_atomic_dec(struct pipe_atomic *v)
+{
+   (void) __sync_sub_and_fetch(&v->count, 1);
+}
+
+static INLINE int32_t
+p_atomic_cmpxchg(struct pipe_atomic *v, int32_t old, int32_t _new)
+{
+   return __sync_val_compare_and_swap(&v->count, 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"
+
+struct pipe_atomic
+{
+   int32_t count;
+};
+
+#define p_atomic_set(_v, _i) ((_v)->count = (_i))
+#define p_atomic_read(_v) ((_v)->count)
+#define p_atomic_dec_zero(_v) ((boolean) --(_v)->count)
+#define p_atomic_inc(_v) ((void) (_v)->count++)
+#define p_atomic_dec(_v) ((void) (_v)->count--)
+#define p_atomic_cmpxchg(_v, old, _new) ((_v)->count == old ? (_v)->count = (_new) : (_v)->count)
+
+#endif
+
+
+/* Locally coded assembly for MSVC on x86:
+ */
+#if defined(PIPE_ATOMIC_ASM_MSVC_X86)
+
+#define PIPE_ATOMIC "MSVC x86 assembly"
+
+struct pipe_atomic
+{
+   int32_t count;
+};
+
+#define p_atomic_set(_v, _i) ((_v)->count = (_i))
+#define p_atomic_read(_v) ((_v)->count)
+
+static INLINE boolean
+p_atomic_dec_zero(struct pipe_atomic *v)
+{
+   int32_t *pcount = &v->count;
+   unsigned char c;
+
+   __asm {
+      mov       eax, [pcount]
+      lock dec  dword ptr [eax]
+      sete      byte ptr [c]
+   }
+
+   return c != 0;
+}
+
+static INLINE void
+p_atomic_inc(struct pipe_atomic *v)
+{
+   int32_t *pcount = &v->count;
+
+   __asm {
+      mov       eax, [pcount]
+      lock inc  dword ptr [eax]
+   }
+}
+
+static INLINE void
+p_atomic_dec(struct pipe_atomic *v)
+{
+   int32_t *pcount = &v->count;
+
+   __asm {
+      mov       eax, [pcount]
+      lock dec  dword ptr [eax]
+   }
+}
+
+static INLINE int32_t
+p_atomic_cmpxchg(struct pipe_atomic *v, int32_t old, int32_t _new)
+{
+   int32_t *pcount = &v->count;
+   int32_t orig;
+
+   __asm {
+      mov ecx, [pcount]
+      mov eax, [old]
+      mov edx, [_new]
+      lock cmpxchg [ecx], edx
+      mov [orig], eax
+   }
+
+   return orig;
+}
+#endif
+
+
+#if defined(PIPE_ATOMIC_OS_MS_INTERLOCK)
+
+#define PIPE_ATOMIC "MS userspace interlocks"
+
+#include <windows.h>
+
+struct pipe_atomic
+{
+   volatile long count;
+};
+
+#define p_atomic_set(_v, _i) ((_v)->count = (_i))
+#define p_atomic_read(_v) ((_v)->count)
+
+static INLINE boolean
+p_atomic_dec_zero(struct pipe_atomic *v)
+{
+   return InterlockedDecrement(&v->count) == 0;
+}
+
+static INLINE void
+p_atomic_inc(struct pipe_atomic *v)
+{
+   InterlockedIncrement(&v->count);
+}
+
+static INLINE void
+p_atomic_dec(struct pipe_atomic *v)
+{
+   InterlockedDecrement(&v->count);
+}
+
+static INLINE int32_t
+p_atomic_cmpxchg(struct pipe_atomic *v, int32_t old, int32_t _new)
+{
+   return InterlockedCompareExchange(&v->count, _new, old);
+}
+
+#endif
+
+
+
+#if defined(PIPE_ATOMIC_MUTEX)
+
+#define PIPE_ATOMIC "mutex-based fallback"
+
+#include "pipe/p_thread.h"
+
+/**
+ * This implementation should really not be used.
+ * Add an assembly port instead. It may abort and
+ * doesn't destroy used mutexes.
+ */
+
+struct pipe_atomic {
+   pipe_mutex mutex;
+   int32_t count;
+};
+
+static INLINE void
+p_atomic_set(struct pipe_atomic *v, int32_t i)
+{
+   pipe_mutex_init(v->mutex);
+   pipe_mutex_lock(v->mutex);
+   v->count = i;
+   pipe_mutex_unlock(v->mutex);
+}
+
+static INLINE int32_t
+p_atomic_read(struct pipe_atomic *v)
+{
+   int32_t ret;
+
+   pipe_mutex_lock(v->mutex);
+   ret = v->count;
+   pipe_mutex_unlock(v->mutex);
+   return ret;
+}
+
+static INLINE void
+p_atomic_inc(struct pipe_atomic *v)
+{
+   pipe_mutex_lock(v->mutex);
+   ++v->count;
+   pipe_mutex_unlock(v->mutex);
+}
+
+static INLINE void
+p_atomic_dec(struct pipe_atomic *v)
+{
+   pipe_mutex_lock(v->mutex);
+   --v->count;
+   pipe_mutex_unlock(v->mutex);
+}
+
+static INLINE boolean
+p_atomic_dec_zero(struct pipe_atomic *v)
+{
+   boolean ret;
+
+   pipe_mutex_lock(v->mutex);
+   ret = (--v->count == 0);
+   pipe_mutex_unlock(v->mutex);
+   return ret;
+}
+
+static INLINE int32_t
+p_atomic_cmpxchg(struct pipe_atomic *v, int32_t old, int32_t _new)
+{
+   int32_t ret;
+
+   pipe_mutex_lock(v->mutex);
+   ret = v->count;
+   if (ret == old)
+      v->count = _new;
+   pipe_mutex_unlock(v->mutex);
+
+   return ret;
+}
+
+#endif 
+
+
+#ifndef PIPE_ATOMIC
+#error "No pipe_atomic implementation selected"
+#endif
+
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* P_ATOMIC_H */