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prefetching does not help length of match

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l_lx_elf64amd.S amd_d_nrv2b.S amd_d_nrv2e.S

committer: jreiser <jreiser> 1132290120 +0000
This commit is contained in:
John Reiser
2005-11-18 05:02:00 +00:00
parent aacfb8820e
commit bff2a63ea2
3 changed files with 21 additions and 9 deletions
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src/stub/l_lx_elf64amd.S
+14 -2
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@@ -102,6 +102,17 @@ ra_setup:
*/
/* jump on next bit {0,1} with prediction {y==>likely, n==>unlikely} */
/* Prediction omitted for now. */
/* On refill: prefetch next byte, for latency reduction on literals and offsets. */
#define jnextb0np jnextb0yp
#define jnextb0yp GETBITp; jnc
#define jnextb1np jnextb1yp
#define jnextb1yp GETBITp; jc
#define GETBITp \
addl bits,bits; jnz 0f; \
movl (%rsi),bits; subq $-4,%rsi; \
adcl bits,bits; movb (%rsi),%dl; \
0:
/* Same, but without prefetch (not useful for length of match.) */
#define jnextb0n jnextb0y
#define jnextb0y GETBIT; jnc
#define jnextb1n jnextb1y
@@ -109,11 +120,12 @@ ra_setup:
#define GETBIT \
addl bits,bits; jnz 0f; \
movl (%rsi),bits; subq $-4,%rsi; \
adcl bits,bits; movb (%rsi),%dl; \
adcl bits,bits; \
0:
/* rotate next bit into bottom bit of reg */
#define getnextb(reg) call *%r11; adcl reg,reg
#define getnextbp(reg) call *%r11; adcl reg,reg
#define getnextb(reg) getnextbp(reg)
ALIGN(1<<3)
getbit: