diff options
Diffstat (limited to 'arch/sparc/lib/strlen.S')
| -rw-r--r-- | arch/sparc/lib/strlen.S | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/arch/sparc/lib/strlen.S b/arch/sparc/lib/strlen.S new file mode 100644 index 000000000000..ed9a763368cd --- /dev/null +++ b/arch/sparc/lib/strlen.S @@ -0,0 +1,81 @@ +/* strlen.S: Sparc optimized strlen code + * Hand optimized from GNU libc's strlen + * Copyright (C) 1991,1996 Free Software Foundation + * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu) + * Copyright (C) 1996 Jakub Jelinek (jj@sunsite.mff.cuni.cz) + */ + +#define LO_MAGIC 0x01010101 +#define HI_MAGIC 0x80808080 + +0: + ldub [%o0], %o5 + cmp %o5, 0 + be 1f + add %o0, 1, %o0 + andcc %o0, 3, %g0 + be 4f + or %o4, %lo(HI_MAGIC), %o3 + ldub [%o0], %o5 + cmp %o5, 0 + be 2f + add %o0, 1, %o0 + andcc %o0, 3, %g0 + be 5f + sethi %hi(LO_MAGIC), %o4 + ldub [%o0], %o5 + cmp %o5, 0 + be 3f + add %o0, 1, %o0 + b 8f + or %o4, %lo(LO_MAGIC), %o2 +1: + retl + mov 0, %o0 +2: + retl + mov 1, %o0 +3: + retl + mov 2, %o0 + + .align 4 + .global strlen +strlen: + mov %o0, %o1 + andcc %o0, 3, %g0 + bne 0b + sethi %hi(HI_MAGIC), %o4 + 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 + be 8b + add %o0, 4, %o0 + + /* Check every byte. */ + srl %o5, 24, %g5 + andcc %g5, 0xff, %g0 + be 1f + add %o0, -4, %o4 + srl %o5, 16, %g5 + andcc %g5, 0xff, %g0 + be 1f + add %o4, 1, %o4 + srl %o5, 8, %g5 + andcc %g5, 0xff, %g0 + be 1f + add %o4, 1, %o4 + andcc %o5, 0xff, %g0 + bne,a 2b + ld [%o0], %o5 + add %o4, 1, %o4 +1: + retl + sub %o4, %o1, %o0 |