[FFmpeg-devel] [PATCH] Small speedups in ff_emulated_edge_mc x86 SIMD.
Ronald S. Bultje
rsbultje at gmail.com
Sat Oct 26 14:24:09 CEST 2013
Don't use word-size multiplications if size == 2, and if we're using
SIMD instructions (size >= 8), complete leftover 4byte sets using movd,
not mov. Both of these changes lead to minor speedups. Lastly, fix a
bug in a %if statement where we used '%%' instead of '&&'.
---
libavcodec/x86/videodsp.asm | 36 ++++++++++++++++++------------------
1 file changed, 18 insertions(+), 18 deletions(-)
diff --git a/libavcodec/x86/videodsp.asm b/libavcodec/x86/videodsp.asm
index 6d5b57e..1ac0257 100644
--- a/libavcodec/x86/videodsp.asm
+++ b/libavcodec/x86/videodsp.asm
@@ -344,10 +344,6 @@ VERTICAL_EXTEND 16, 22
; obviously not the same on both sides.
%macro READ_V_PIXEL 2
-%if %1 == 2
- movzx valw, byte %2
- imul valw, 0x0101
-%else
movzx vald, byte %2
imul vald, 0x01010101
%if %1 >= 8
@@ -356,13 +352,15 @@ VERTICAL_EXTEND 16, 22
pshufd m0, m0, q0000
%else
punpckldq m0, m0
-%endif
-%endif ; %1 >= 8
-%endif
+%endif ; mmsize == 16
+%endif ; %1 > 16
%endmacro ; READ_V_PIXEL
%macro WRITE_V_PIXEL 2
%assign %%off 0
+
+%if %1 >= 8
+
%rep %1/mmsize
movu [%2+%%off], m0
%assign %%off %%off+mmsize
@@ -378,27 +376,29 @@ VERTICAL_EXTEND 16, 22
%assign %%off %%off+8
%endif
%endif ; %1-%%off >= 8
-%endif
+%endif ; mmsize == 16
%if %1-%%off >= 4
-%if %1 > 8 %% %1-%%off > 4
+%if %1 > 8 && %1-%%off > 4
movq [%2+%1-8], m0
%assign %%off %1
-%elif %1 >= 8 && %1-%%off >= 4
- movd [%2+%%off], m0
-%assign %%off %%off+4
%else
- mov [%2+%%off], vald
+ movd [%2+%%off], m0
%assign %%off %%off+4
%endif
%endif ; %1-%%off >= 4
-%if %1-%%off >= 2
-%if %1 >= 8
- movd [%2+%1-4], m0
-%else
+%else ; %1 < 8
+
+%rep %1/4
+ mov [%2+%%off], vald
+%assign %%off %%off+4
+%endrep ; %1/4
+
+%endif ; %1 >=/< 8
+
+%if %1-%%off == 2
mov [%2+%%off], valw
-%endif
%endif ; (%1-%%off)/2
%endmacro ; WRITE_V_PIXEL
--
1.8.4
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