Chiebot-Mirror
/
FFmpeg
mirror of https://github.com/FFmpeg/FFmpeg.git
8
0
Fork 0
Code Issues Projects Releases Wiki Activity

H.264: optimize CABAC x86 asm for Atom

Browse Source
pull/2/head
Jason Garrett-Glaser 14 years ago
parent 8dcf518430
commit 6c32576548
3 changed files with 12 additions and 16 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 2
      libavcodec/h264_cabac.c
  2. 15
      libavcodec/x86/cabac.h
  3. 11
      libavcodec/x86/h264_i386.h

2
libavcodec/h264_cabac.c
Unescape View File

@ -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);

15
libavcodec/x86/cabac.h
Unescape View File

@ -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"\

11
libavcodec/x86/h264_i386.h
Unescape View File

@ -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"

Write Preview
Loading…
Cancel
Save