gallium/llvmpipe: add an optimised 32-bit memset

This might have other users beyond filling/clearing buffers,

increase a fullscreen 4k gears from 68->74 fps on my Ryzen
since gears is really just a clear benchmark, and this helps
clearing.

Reviewed-by: Marek Olšák <[email protected]>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4394>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4394>

3 files changed, 49 insertions, 0 deletions

diff --git a/src/util/Makefile.sources b/src/util/Makefile.sources
index 644839bd09a..0e8fbb7ee85 100644
--- a/src/util/Makefile.sources
+++ b/src/util/Makefile.sources
@@ -119,6 +119,7 @@ MESA_UTIL_FILES := \
 	os_memory_stdc.h \
 	os_memory.h \
 	u_memory.h \
+	u_memset.h \
 	u_mm.h \
 	u_mm.c \
 	vma.c \
diff --git a/src/util/meson.build b/src/util/meson.build
index 0a2b2e4284e..ff25a9ea851 100644
--- a/src/util/meson.build
+++ b/src/util/meson.build
@@ -112,6 +112,7 @@ files_mesa_util = files(
   'u_vector.h',
   'u_math.c',
   'u_math.h',
+  'u_memset.h',
   'u_mm.c',
   'u_mm.h',
   'u_debug.c',
diff --git a/src/util/u_memset.h b/src/util/u_memset.h
new file mode 100644
index 00000000000..df8cf80b64a
--- /dev/null
+++ b/src/util/u_memset.h
@@ -0,0 +1,47 @@
+/**************************************************************************
+ *
+ * Copyright 2020 Red Hat
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+
+#include "pipe/p_config.h"
+
+static inline void *
+util_memset32(void *s, uint32_t ui, size_t n)
+{
+#if defined(PIPE_CC_GCC) && defined(PIPE_ARCH_X86_64)
+   long d0, d1;
+   __asm__ volatile("rep\n\t"
+                    "stosl"
+                    : "=&c" (d0), "=&D" (d1)
+                    : "a" (ui), "1" (s), "0" (n)
+                    : "memory");
+   return s;
+#else
+   uint32_t *xs = (uint32_t *)s;
+   while (n--)
+      *xs++ = ui;
+   return s;
+#endif
+}