[Mesa-dev] [PATCH 1/2] mesa: Add a streaming load memcpy implementation.
Matt Turner
mattst88 at gmail.com
Tue Nov 5 13:35:29 PST 2013
Uses SSE 4.1's MOVNTDQA instruction (streaming load) to read from
uncached memory without polluting the cache.
---
We should add runtime detection support later.
src/mesa/Makefile.am | 10 +++++
src/mesa/main/streaming-load-memcpy.c | 85 +++++++++++++++++++++++++++++++++++
src/mesa/main/streaming-load-memcpy.h | 33 ++++++++++++++
3 files changed, 128 insertions(+)
create mode 100644 src/mesa/main/streaming-load-memcpy.c
create mode 100644 src/mesa/main/streaming-load-memcpy.h
diff --git a/src/mesa/Makefile.am b/src/mesa/Makefile.am
index b4ad9fc..f34ca82 100644
--- a/src/mesa/Makefile.am
+++ b/src/mesa/Makefile.am
@@ -100,16 +100,20 @@ MESA_ASM_FILES_FOR_ARCH =
if HAVE_X86_ASM
MESA_ASM_FILES_FOR_ARCH += $(X86_FILES)
AM_CPPFLAGS += -I$(builddir)/x86 -I$(srcdir)/x86
+ARCH_LIBS = libmesa_sse41.la
endif
if HAVE_X86_64_ASM
MESA_ASM_FILES_FOR_ARCH += $(X86_64_FILES)
AM_CPPFLAGS += -I$(builddir)/x86-64 -I$(srcdir)/x86-64
+ARCH_LIBS = libmesa_sse41.la
endif
if HAVE_SPARC_ASM
MESA_ASM_FILES_FOR_ARCH += $(SPARC_FILES)
AM_CPPFLAGS += -I$(builddir)/sparc -I$(srcdir)/sparc
endif
+noinst_LTLIBRARIES += $(ARCH_LIBS)
+
libmesa_la_SOURCES = \
$(MESA_FILES) \
$(PROGRAM_FILES) \
@@ -117,6 +121,7 @@ libmesa_la_SOURCES = \
libmesa_la_LIBADD = \
$(top_builddir)/src/glsl/libglsl.la \
+ $(ARCH_LIBS) \
$()
libmesagallium_la_SOURCES = \
@@ -126,8 +131,13 @@ libmesagallium_la_SOURCES = \
libmesagallium_la_LIBADD = \
$(top_builddir)/src/glsl/libglsl.la \
+ $(ARCH_LIBS) \
$()
+libmesa_sse41_la_SOURCES = \
+ main/streaming-load-memcpy.c
+libmesa_sse41_la_CFLAGS = $(AM_CFLAGS) -msse4.1
+
pkgconfigdir = $(libdir)/pkgconfig
pkgconfig_DATA = gl.pc
diff --git a/src/mesa/main/streaming-load-memcpy.c b/src/mesa/main/streaming-load-memcpy.c
new file mode 100644
index 0000000..d7147af
--- /dev/null
+++ b/src/mesa/main/streaming-load-memcpy.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright © 2013 Intel Corporation
+ *
+ * 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, sublicense,
+ * 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 NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ *
+ * Authors:
+ * Eric Anholt <eric at anholt.net>
+ * Matt Turner <mattst88 at gmail.com>
+ *
+ */
+
+#include "main/macros.h"
+#include "main/streaming-load-memcpy.h"
+#include <smmintrin.h>
+
+/* Copies memory from src to dst, using SSE 4.1's MOVNTDQA to get streaming
+ * read performance from uncached memory.
+ */
+void
+_mesa_streaming_load_memcpy(void *restrict dst, void *restrict src, size_t len)
+{
+ char *restrict d = dst;
+ char *restrict s = src;
+
+ /* If dst and src are not co-aligned, fallback to memcpy(). */
+ if (((uintptr_t)d & 15) != ((uintptr_t)s & 15)) {
+ memcpy(d, s, len);
+ return;
+ }
+
+ /* memcpy() the misaligned header. At the end of this if block, <d> and <s>
+ * are aligned to a 16-byte boundary or <len> == 0.
+ */
+ if ((uintptr_t)d & 15) {
+ uintptr_t bytes_before_alignment_boundary = 16 - ((uintptr_t)d & 15);
+ assert(bytes_before_alignment_boundary < 16);
+
+ memcpy(d, s, MIN2(bytes_before_alignment_boundary, len));
+
+ d = (char *)ALIGN((uintptr_t)d, 16);
+ s = (char *)ALIGN((uintptr_t)s, 16);
+ len -= MIN2(bytes_before_alignment_boundary, len);
+ }
+
+ while (len >= 64) {
+ __m128i *dst_cacheline = (__m128i *)d;
+ __m128i *src_cacheline = (__m128i *)s;
+
+ __m128i temp1 = _mm_stream_load_si128(src_cacheline + 0);
+ __m128i temp2 = _mm_stream_load_si128(src_cacheline + 1);
+ __m128i temp3 = _mm_stream_load_si128(src_cacheline + 2);
+ __m128i temp4 = _mm_stream_load_si128(src_cacheline + 3);
+
+ _mm_store_si128(dst_cacheline + 0, temp1);
+ _mm_store_si128(dst_cacheline + 1, temp2);
+ _mm_store_si128(dst_cacheline + 2, temp3);
+ _mm_store_si128(dst_cacheline + 3, temp4);
+
+ d += 64;
+ s += 64;
+ len -= 64;
+ }
+
+ /* memcpy() the tail. */
+ if (len) {
+ memcpy(d, s, len);
+ }
+}
diff --git a/src/mesa/main/streaming-load-memcpy.h b/src/mesa/main/streaming-load-memcpy.h
new file mode 100644
index 0000000..41eeeec
--- /dev/null
+++ b/src/mesa/main/streaming-load-memcpy.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright © 2013 Intel Corporation
+ *
+ * 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, sublicense,
+ * 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 NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ *
+ * Authors:
+ * Eric Anholt <eric at anholt.net>
+ * Matt Turner <mattst88 at gmail.com>
+ *
+ */
+
+/* Copies memory from src to dst, using SSE 4.1's MOVNTDQA to get streaming
+ * read performance from uncached memory.
+ */
+void
+_mesa_streaming_load_memcpy(void *restrict dst, void *restrict src, size_t len);
--
1.8.3.2
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