From 3f150ffba31e404ca48624dc6af27b85c1704862 Mon Sep 17 00:00:00 2001
From: "Ronald S. Bultje" <rsbultje@gmail.com>
Date: Mon, 9 Jul 2012 02:21:26 +0200
Subject: [PATCH] x86/cpu: implement support for xgetbv through intrinsics
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Signed-off-by: Martin Storsjö <martin@martin.st>
---
configure | 2 ++
libavutil/x86/cpu.c | 11 +++++++++++
2 files changed, 13 insertions(+)
diff --git a/configure b/configure
index a1506c9262a..76ad4c7b701 100755
--- a/configure
+++ b/configure
@@ -1169,6 +1169,7 @@ HAVE_LIST="
windows_h
winsock2_h
xform_asm
+ xgetbv
xmm_clobbers
yasm
"
@@ -2742,6 +2743,7 @@ elif enabled sparc; then
elif enabled x86; then
+ check_code ld immintrin.h "__xgetbv(0)" && enable xgetbv
check_code ld intrin.h "__rdtsc()" && enable rdtsc
check_code ld mmintrin.h "_mm_empty()" && enable mm_empty
diff --git a/libavutil/x86/cpu.c b/libavutil/x86/cpu.c
index 5d77b0c2dfa..dfdc12394c3 100644
--- a/libavutil/x86/cpu.c
+++ b/libavutil/x86/cpu.c
@@ -34,8 +34,19 @@
: "=a" (eax), "=S" (ebx), "=c" (ecx), "=d" (edx) \
: "0" (index))
+#if HAVE_INLINE_ASM
#define xgetbv(index, eax, edx) \
__asm__ (".byte 0x0f, 0x01, 0xd0" : "=a"(eax), "=d"(edx) : "c" (index))
+#elif HAVE_XGETBV
+#include <immintrin.h>
+
+#define xgetbv(index, eax, edx) \
+ do { \
+ uint64_t res = __xgetbv(index); \
+ eax = res; \
+ edx = res >> 32; \
+ } while (0)
+#endif /* HAVE_XGETBV */
#define get_eflags(x) \
__asm__ volatile ("pushfl \n" \
--
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