[FFmpeg-cvslog] H.264: optimize CABAC x86 asm for Atom
Jason Garrett-Glaser
git at videolan.org
Fri Jul 29 02:08:41 CEST 2011
ffmpeg | branch: master | Jason Garrett-Glaser <jason at x264.com> | Tue Jul 26 19:08:05 2011 -0700| [6c3257654801d525aa61e6fb46022a2a3b12c074] | committer: Jason Garrett-Glaser
H.264: optimize CABAC x86 asm for Atom
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=6c3257654801d525aa61e6fb46022a2a3b12c074
---
libavcodec/h264_cabac.c | 2 +-
libavcodec/x86/cabac.h | 15 +++++++--------
libavcodec/x86/h264_i386.h | 11 ++++-------
3 files changed, 12 insertions(+), 16 deletions(-)
diff --git a/libavcodec/h264_cabac.c b/libavcodec/h264_cabac.c
index f7cec5d..065b6e8 100644
--- a/libavcodec/h264_cabac.c
+++ b/libavcodec/h264_cabac.c
@@ -1649,7 +1649,7 @@ static av_always_inline void decode_cabac_residual_internal( H264Context *h, DCT
const uint8_t *sig_off = significant_coeff_flag_offset_8x8[MB_FIELD];
#if ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS)
coeff_count= decode_significance_8x8_x86(CC, significant_coeff_ctx_base, index,
- last_coeff_ctx_base-significant_coeff_ctx_base, sig_off);
+ last_coeff_ctx_base, sig_off);
} else {
coeff_count= decode_significance_x86(CC, max_coeff, significant_coeff_ctx_base, index,
last_coeff_ctx_base-significant_coeff_ctx_base);
diff --git a/libavcodec/x86/cabac.h b/libavcodec/x86/cabac.h
index 52bea9c..1ad74ff 100644
--- a/libavcodec/x86/cabac.h
+++ b/libavcodec/x86/cabac.h
@@ -34,8 +34,8 @@
"cmova %%ecx , "range" \n\t"\
"sbb %%ecx , %%ecx \n\t"\
"and %%ecx , "tmp" \n\t"\
- "sub "tmp" , "low" \n\t"\
- "xor %%ecx , "ret" \n\t"
+ "xor %%ecx , "ret" \n\t"\
+ "sub "tmp" , "low" \n\t"
#else /* HAVE_FAST_CMOV */
#define BRANCHLESS_GET_CABAC_UPDATE(ret, cabac, statep, low, lowword, range, tmp)\
"mov "tmp" , %%ecx \n\t"\
@@ -62,21 +62,20 @@
"movzbl " MANGLE(ff_h264_norm_shift) "("range"), %%ecx \n\t"\
"shl %%cl , "range" \n\t"\
"movzbl "MANGLE(ff_h264_mlps_state)"+128("ret"), "tmp" \n\t"\
- "mov "tmpbyte" , "statep" \n\t"\
"shl %%cl , "low" \n\t"\
+ "mov "tmpbyte" , "statep" \n\t"\
"test "lowword" , "lowword" \n\t"\
" jnz 1f \n\t"\
"mov "byte"("cabac"), %%"REG_c" \n\t"\
+ "add $2 , "byte "("cabac") \n\t"\
"movzwl (%%"REG_c") , "tmp" \n\t"\
- "bswap "tmp" \n\t"\
- "shr $15 , "tmp" \n\t"\
- "sub $0xFFFF , "tmp" \n\t"\
- "add $2 , %%"REG_c" \n\t"\
- "mov %%"REG_c" , "byte "("cabac") \n\t"\
"lea -1("low") , %%ecx \n\t"\
"xor "low" , %%ecx \n\t"\
"shr $15 , %%ecx \n\t"\
+ "bswap "tmp" \n\t"\
+ "shr $15 , "tmp" \n\t"\
"movzbl " MANGLE(ff_h264_norm_shift) "(%%ecx), %%ecx \n\t"\
+ "sub $0xFFFF , "tmp" \n\t"\
"neg %%ecx \n\t"\
"add $7 , %%ecx \n\t"\
"shl %%cl , "tmp" \n\t"\
diff --git a/libavcodec/x86/h264_i386.h b/libavcodec/x86/h264_i386.h
index 9c86210..0151cd5 100644
--- a/libavcodec/x86/h264_i386.h
+++ b/libavcodec/x86/h264_i386.h
@@ -72,8 +72,7 @@ static int decode_significance_x86(CABACContext *c, int max_coeff,
"test $1, %4 \n\t"
" jnz 4f \n\t"
- "add $4, %0 \n\t"
- "mov %0, %2 \n\t"
+ "add $4, %2 \n\t"
"3: \n\t"
"add $1, %1 \n\t"
@@ -101,7 +100,7 @@ static int decode_significance_x86(CABACContext *c, int max_coeff,
static int decode_significance_8x8_x86(CABACContext *c,
uint8_t *significant_coeff_ctx_base,
- int *index, x86_reg last_off, const uint8_t *sig_off){
+ int *index, uint8_t *last_coeff_ctx_base, const uint8_t *sig_off){
int minusindex= 4-(intptr_t)index;
int bit;
x86_reg coeff_count;
@@ -128,7 +127,6 @@ static int decode_significance_8x8_x86(CABACContext *c,
" jz 3f \n\t"
"movzbl "MANGLE(last_coeff_flag_offset_8x8)"(%k6), %k6\n\t"
- "add %9, %6 \n\t"
"add %11, %6 \n\t"
BRANCHLESS_GET_CABAC("%4", "%7", "(%6)", "%3",
@@ -141,8 +139,7 @@ static int decode_significance_8x8_x86(CABACContext *c,
"test $1, %4 \n\t"
" jnz 4f \n\t"
- "add $4, %0 \n\t"
- "mov %0, %2 \n\t"
+ "add $4, %2 \n\t"
"3: \n\t"
"addl $1, %k6 \n\t"
@@ -159,7 +156,7 @@ static int decode_significance_8x8_x86(CABACContext *c,
"movl %3, %a13(%7) \n\t"
:"=&q"(coeff_count),"+m"(last), "+m"(index), "=&r"(low), "=&r"(bit),
"=&r"(range), "=&r"(state)
- :"r"(c), "m"(minusindex), "m"(significant_coeff_ctx_base), "m"(sig_off), "m"(last_off),
+ :"r"(c), "m"(minusindex), "m"(significant_coeff_ctx_base), "m"(sig_off), "m"(last_coeff_ctx_base),
"i"(offsetof(CABACContext, range)), "i"(offsetof(CABACContext, low)),
"i"(offsetof(CABACContext, bytestream))
: "%"REG_c, "memory"
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