| /* strlen.S: Sparc optimized strlen code |
| * Hand optimized from GNU libc's strlen |
| * Copyright (C) 1991,1996 Free Software Foundation |
| * Copyright (C) 1996,2008 David S. Miller (davem@davemloft.net) |
| * Copyright (C) 1996, 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz) |
| */ |
| |
| #include <linux/linkage.h> |
| #include <asm/asm.h> |
| |
| #define LO_MAGIC 0x01010101 |
| #define HI_MAGIC 0x80808080 |
| |
| .text |
| ENTRY(strlen) |
| mov %o0, %o1 |
| andcc %o0, 3, %g0 |
| BRANCH32(be, pt, 9f) |
| sethi %hi(HI_MAGIC), %o4 |
| ldub [%o0], %o5 |
| BRANCH_REG_ZERO(pn, %o5, 11f) |
| add %o0, 1, %o0 |
| andcc %o0, 3, %g0 |
| BRANCH32(be, pn, 4f) |
| or %o4, %lo(HI_MAGIC), %o3 |
| ldub [%o0], %o5 |
| BRANCH_REG_ZERO(pn, %o5, 12f) |
| add %o0, 1, %o0 |
| andcc %o0, 3, %g0 |
| BRANCH32(be, pt, 5f) |
| sethi %hi(LO_MAGIC), %o4 |
| ldub [%o0], %o5 |
| BRANCH_REG_ZERO(pn, %o5, 13f) |
| add %o0, 1, %o0 |
| BRANCH32(ba, pt, 8f) |
| or %o4, %lo(LO_MAGIC), %o2 |
| 9: |
| or %o4, %lo(HI_MAGIC), %o3 |
| 4: |
| sethi %hi(LO_MAGIC), %o4 |
| 5: |
| or %o4, %lo(LO_MAGIC), %o2 |
| 8: |
| ld [%o0], %o5 |
| 2: |
| sub %o5, %o2, %o4 |
| andcc %o4, %o3, %g0 |
| BRANCH32(be, pt, 8b) |
| add %o0, 4, %o0 |
| |
| /* Check every byte. */ |
| srl %o5, 24, %g7 |
| andcc %g7, 0xff, %g0 |
| BRANCH32(be, pn, 1f) |
| add %o0, -4, %o4 |
| srl %o5, 16, %g7 |
| andcc %g7, 0xff, %g0 |
| BRANCH32(be, pn, 1f) |
| add %o4, 1, %o4 |
| srl %o5, 8, %g7 |
| andcc %g7, 0xff, %g0 |
| BRANCH32(be, pn, 1f) |
| add %o4, 1, %o4 |
| andcc %o5, 0xff, %g0 |
| BRANCH32_ANNUL(bne, pt, 2b) |
| ld [%o0], %o5 |
| add %o4, 1, %o4 |
| 1: |
| retl |
| sub %o4, %o1, %o0 |
| 11: |
| retl |
| mov 0, %o0 |
| 12: |
| retl |
| mov 1, %o0 |
| 13: |
| retl |
| mov 2, %o0 |
| ENDPROC(strlen) |
