[FFmpeg-cvslog] cabac: remove BRANCHLESS_CABAC_DECODER switch
Mans Rullgard
git at videolan.org
Tue Jun 21 03:45:21 CEST 2011
ffmpeg | branch: master | Mans Rullgard <mans at mansr.com> | Mon Jun 20 01:49:38 2011 +0100| [8fcc0e7978e03cbf7e6d872d34ca1ea4a7d97b87] | committer: Mans Rullgard
cabac: remove BRANCHLESS_CABAC_DECODER switch
The code does not compile without this set.
Signed-off-by: Mans Rullgard <mans at mansr.com>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=8fcc0e7978e03cbf7e6d872d34ca1ea4a7d97b87
---
libavcodec/cabac.c | 8 ----
libavcodec/cabac.h | 106 +---------------------------------------------------
2 files changed, 1 insertions(+), 113 deletions(-)
diff --git a/libavcodec/cabac.c b/libavcodec/cabac.c
index 098cd6f..691beb0 100644
--- a/libavcodec/cabac.c
+++ b/libavcodec/cabac.c
@@ -161,19 +161,11 @@ void ff_init_cabac_states(CABACContext *c){
ff_h264_mps_state[2*i+1]= 2*mps_state[i]+1;
if( i ){
-#ifdef BRANCHLESS_CABAC_DECODER
ff_h264_mlps_state[128-2*i-1]= 2*lps_state[i]+0;
ff_h264_mlps_state[128-2*i-2]= 2*lps_state[i]+1;
}else{
ff_h264_mlps_state[128-2*i-1]= 1;
ff_h264_mlps_state[128-2*i-2]= 0;
-#else
- ff_h264_lps_state[2*i+0]= 2*lps_state[i]+0;
- ff_h264_lps_state[2*i+1]= 2*lps_state[i]+1;
- }else{
- ff_h264_lps_state[2*i+0]= 1;
- ff_h264_lps_state[2*i+1]= 0;
-#endif
}
}
}
diff --git a/libavcodec/cabac.h b/libavcodec/cabac.h
index 53e327d..6b7ef45 100644
--- a/libavcodec/cabac.h
+++ b/libavcodec/cabac.h
@@ -35,7 +35,6 @@
#define CABAC_BITS 16
#define CABAC_MASK ((1<<CABAC_BITS)-1)
-#define BRANCHLESS_CABAC_DECODER 1
typedef struct CABACContext{
int low;
@@ -322,89 +321,6 @@ static av_always_inline int get_cabac_inline(CABACContext *c, uint8_t * const st
#if ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS)
int bit;
-#ifndef BRANCHLESS_CABAC_DECODER
- __asm__ volatile(
- "movzbl (%1), %0 \n\t"
- "movl "RANGE "(%2), %%ebx \n\t"
- "movl "RANGE "(%2), %%edx \n\t"
- "andl $0xC0, %%ebx \n\t"
- "movzbl "MANGLE(ff_h264_lps_range)"(%0, %%ebx, 2), %%esi\n\t"
- "movl "LOW "(%2), %%ebx \n\t"
-//eax:state ebx:low, edx:range, esi:RangeLPS
- "subl %%esi, %%edx \n\t"
- "movl %%edx, %%ecx \n\t"
- "shll $17, %%ecx \n\t"
- "cmpl %%ecx, %%ebx \n\t"
- " ja 1f \n\t"
-
-#if 1
- //athlon:4067 P3:4110
- "lea -0x100(%%edx), %%ecx \n\t"
- "shr $31, %%ecx \n\t"
- "shl %%cl, %%edx \n\t"
- "shl %%cl, %%ebx \n\t"
-#else
- //athlon:4057 P3:4130
- "cmp $0x100, %%edx \n\t" //FIXME avoidable
- "setb %%cl \n\t"
- "shl %%cl, %%edx \n\t"
- "shl %%cl, %%ebx \n\t"
-#endif
- "movzbl "MANGLE(ff_h264_mps_state)"(%0), %%ecx \n\t"
- "movb %%cl, (%1) \n\t"
-//eax:state ebx:low, edx:range, esi:RangeLPS
- "test %%bx, %%bx \n\t"
- " jnz 2f \n\t"
- "mov "BYTE "(%2), %%"REG_S" \n\t"
- "subl $0xFFFF, %%ebx \n\t"
- "movzwl (%%"REG_S"), %%ecx \n\t"
- "bswap %%ecx \n\t"
- "shrl $15, %%ecx \n\t"
- "add $2, %%"REG_S" \n\t"
- "addl %%ecx, %%ebx \n\t"
- "mov %%"REG_S", "BYTE "(%2) \n\t"
- "jmp 2f \n\t"
- "1: \n\t"
-//eax:state ebx:low, edx:range, esi:RangeLPS
- "subl %%ecx, %%ebx \n\t"
- "movl %%esi, %%edx \n\t"
- "movzbl " MANGLE(ff_h264_norm_shift) "(%%esi), %%ecx \n\t"
- "shll %%cl, %%ebx \n\t"
- "shll %%cl, %%edx \n\t"
- "movzbl "MANGLE(ff_h264_lps_state)"(%0), %%ecx \n\t"
- "movb %%cl, (%1) \n\t"
- "add $1, %0 \n\t"
- "test %%bx, %%bx \n\t"
- " jnz 2f \n\t"
-
- "mov "BYTE "(%2), %%"REG_c" \n\t"
- "movzwl (%%"REG_c"), %%esi \n\t"
- "bswap %%esi \n\t"
- "shrl $15, %%esi \n\t"
- "subl $0xFFFF, %%esi \n\t"
- "add $2, %%"REG_c" \n\t"
- "mov %%"REG_c", "BYTE "(%2) \n\t"
-
- "leal -1(%%ebx), %%ecx \n\t"
- "xorl %%ebx, %%ecx \n\t"
- "shrl $15, %%ecx \n\t"
- "movzbl " MANGLE(ff_h264_norm_shift) "(%%ecx), %%ecx \n\t"
- "neg %%ecx \n\t"
- "add $7, %%ecx \n\t"
-
- "shll %%cl , %%esi \n\t"
- "addl %%esi, %%ebx \n\t"
- "2: \n\t"
- "movl %%edx, "RANGE "(%2) \n\t"
- "movl %%ebx, "LOW "(%2) \n\t"
- :"=&a"(bit) //FIXME this is fragile gcc either runs out of registers or miscompiles it (for example if "+a"(bit) or "+m"(*state) is used
- :"r"(state), "r"(c)
- : "%"REG_c, "%ebx", "%edx", "%"REG_S, "memory"
- );
- bit&=1;
-#else /* BRANCHLESS_CABAC_DECODER */
-
-
#if HAVE_FAST_CMOV
#define BRANCHLESS_GET_CABAC_UPDATE(ret, cabac, statep, low, lowword, range, tmp, tmpbyte)\
"mov "tmp" , %%ecx \n\t"\
@@ -474,31 +390,12 @@ static av_always_inline int get_cabac_inline(CABACContext *c, uint8_t * const st
: "%"REG_c, "%ebx", "%edx", "%esi", "memory"
);
bit&=1;
-#endif /* BRANCHLESS_CABAC_DECODER */
#else /* ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS) */
int s = *state;
int RangeLPS= ff_h264_lps_range[2*(c->range&0xC0) + s];
- int bit, lps_mask av_unused;
+ int bit, lps_mask;
c->range -= RangeLPS;
-#ifndef BRANCHLESS_CABAC_DECODER
- if(c->low < (c->range<<(CABAC_BITS+1))){
- bit= s&1;
- *state= ff_h264_mps_state[s];
- renorm_cabac_decoder_once(c);
- }else{
- bit= ff_h264_norm_shift[RangeLPS];
- c->low -= (c->range<<(CABAC_BITS+1));
- *state= ff_h264_lps_state[s];
- c->range = RangeLPS<<bit;
- c->low <<= bit;
- bit= (s&1)^1;
-
- if(!(c->low & CABAC_MASK)){
- refill2(c);
- }
- }
-#else /* BRANCHLESS_CABAC_DECODER */
lps_mask= ((c->range<<(CABAC_BITS+1)) - c->low)>>31;
c->low -= (c->range<<(CABAC_BITS+1)) & lps_mask;
@@ -513,7 +410,6 @@ static av_always_inline int get_cabac_inline(CABACContext *c, uint8_t * const st
c->low <<= lps_mask;
if(!(c->low & CABAC_MASK))
refill2(c);
-#endif /* BRANCHLESS_CABAC_DECODER */
#endif /* ARCH_X86 && HAVE_7REGS && HAVE_EBX_AVAILABLE && !defined(BROKEN_RELOCATIONS) */
return bit;
}
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