diff options
| -rw-r--r-- | ChangeLog | 9 | ||||
| -rw-r--r-- | sysdeps/i386/i486/bits/string.h | 189 |
2 files changed, 170 insertions, 28 deletions
diff --git a/ChangeLog b/ChangeLog index 629c97134a..42ce9de41d 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,12 @@ +1999-04-30 Ulrich Drepper <drepper@cygnus.com> + + * string/bits/string2.h: Fix bugs I introduced in last change. + + * sysdeps/i386/i486/bits/string.h (memcmp): Don't introduce partial + register stall. + Extend memset optimization. + Correct i686 version of memchr. + 1999-04-30 Roland McGrath <roland@baalperazim.frob.com> * sysdeps/i386/bzero.c: Add #undef __bzero. diff --git a/sysdeps/i386/i486/bits/string.h b/sysdeps/i386/i486/bits/string.h index cb0229b5cd..2aa0b509b8 100644 --- a/sysdeps/i386/i486/bits/string.h +++ b/sysdeps/i386/i486/bits/string.h @@ -176,7 +176,7 @@ memcmp (__const void *__s1, __const void *__s2, size_t __n) "repe; cmpsb\n\t" "je 1f\n\t" "sbbl %0,%0\n\t" - "orb $1,%b0\n" + "orl $1,%0\n" "1:" : "=a" (__res), "=&S" (__d0), "=&D" (__d1), "=&c" (__d2) : "0" (0), "1" (__s1), "2" (__s2), "3" (__n) @@ -189,24 +189,157 @@ memcmp (__const void *__s1, __const void *__s2, size_t __n) /* Set N bytes of S to C. */ #define _HAVE_STRING_ARCH_memset 1 #define memset(s, c, n) \ - (__extension__ (__builtin_constant_p (c) \ - ? memset (s, c, n) \ - : (__builtin_constant_p (n) \ - ? __memset_gc (s, c, n) \ - : __memset_gg (s, c, n)))) + (__extension__ (__builtin_constant_p (n) && (n) <= 16 \ + ? (__builtin_constant_p (c) \ + ? __memset_gc (s, ((unsigned char) (c)) * 0x01010101, n) \ + : ((n) == 1 \ + ? __memset_c1 (s, c) \ + : __memset_gc (s, c, n))) \ + : (__builtin_constant_p (c) \ + ? (__builtin_constant_p (n) \ + ? __memset_ccn (s, c, n) \ + : __memset_gg (s, c, n)) \ + : (__builtin_constant_p (n) \ + ? __memset_gcn (s, c, n) \ + : __memset_gg (s, c, n))))) + +#define __memset_c1(s, c) ({ void *__s = (s); \ + *((__uint8_t *) __s) = (__uint8_t) (c); __s; }) + #define __memset_gc(s, c, n) \ - ((n) == 0 \ - ? (s) \ - : (((n) % 4== 0) \ - ? __memset_gc_by4 (s, c, n) \ - : (((n) % 2 == 0) \ - ? __memset_gc_by2 (s, c, n) \ - : __memset_gg (s, c, n)))) + ({ void *__s = (s); \ + __uint32_t *__ts = (__uint32_t *) __s; \ + __uint8_t __c = (__uint8_t) (c); \ + \ + /* We apply a trick here. `gcc' would implement the following \ + assignments using absolute operands. But this uses to much \ + memory (7, instead of 4 bytes). */ \ + if (n >= 5) \ + __asm__ __volatile__ ("" : "=r" (__c) : "0" (__c)); \ + \ + /* This `switch' statement will be removed at compile-time. */ \ + switch (n) \ + { \ + case 15: \ + *__ts++ = __c * 0x01010101; \ + case 11: \ + *__ts++ = __c * 0x01010101; \ + case 7: \ + *__ts++ = __c * 0x01010101; \ + case 3: \ + *((__uint16_t *) __ts)++ = __c * 0x0101; \ + *((__uint8_t *) __ts) = __c; \ + break; \ + \ + case 14: \ + *__ts++ = __c * 0x01010101; \ + case 10: \ + *__ts++ = __c * 0x01010101; \ + case 6: \ + *__ts++ = __c * 0x01010101; \ + case 2: \ + *((__uint16_t *) __ts) = __c * 0x0101; \ + break; \ + \ + case 13: \ + *__ts++ = __c * 0x01010101; \ + case 9: \ + *__ts++ = __c * 0x01010101; \ + case 5: \ + *__ts++ = __c * 0x01010101; \ + case 1: \ + *((__uint8_t *) __ts) = __c; \ + break; \ + \ + case 16: \ + *__ts++ = __c * 0x01010101; \ + case 12: \ + *__ts++ = __c * 0x01010101; \ + case 8: \ + *__ts++ = __c * 0x01010101; \ + case 4: \ + *__ts = __c * 0x01010101; \ + case 0: \ + break; \ + } \ + \ + __s; }) + +#define __memset_ccn(s, c, n) \ + (((n) % 4 == 0) \ + ? __memset_ccn_by4 (s, ((__uint8_t) (c)) * 0x01010101, n) \ + : (((n) % 2 == 0) \ + ? __memset_ccn_by2 (s, ((__uint8_t) (c)) * 0x01010101, n) \ + : __memset_gg (s, c, n))) + +__STRING_INLINE void *__memset_ccn_by4 (void *__s, int __c, size_t __n); -__STRING_INLINE void *__memset_gc_by4 (void *__s, int __c, size_t __n); +__STRING_INLINE void * +__memset_ccn_by4 (void *__s, int __c, size_t __n) +{ + register void *__tmp = __s; + register unsigned long int __d0; +#ifdef __i686__ + __asm__ __volatile__ + ("cld\n\t" + "rep; stosl" + : "=&a" (__c), "=&D" (__tmp), "=&c" (__d0) + : "0" ((unsigned int) __c), "1" (__tmp), "2" (__n / 4) + : "memory", "cc"); +#else + __asm__ __volatile__ + ("1:\n\t" + "movl %0,(%1)\n\t" + "addl $4,%1\n\t" + "decl %2\n\t" + "jnz 1b\n" + : "=&q" (__c), "=&r" (__tmp), "=&r" (__d0) + : "0" ((unsigned int) __c), "1" (__tmp), "2" (__n / 4) + : "memory", "cc"); +#endif + return __s; +} + +__STRING_INLINE void *__memset_ccn_by2 (void *__s, int __c, size_t __n); __STRING_INLINE void * -__memset_gc_by4 (void *__s, int __c, size_t __n) +__memset_ccn_by2 (void *__s, int __c, size_t __n) +{ + register unsigned long int __d0, __d1; + register void *__tmp = __s; +#ifdef __i686__ + __asm__ __volatile__ + ("cld\n\t" + "rep; stosl\n" + "stosw" + : "=&a" (__d0), "=&D" (__tmp), "=&c" (__d1) + : "0" ((unsigned int) __c), "1" (__tmp), "2" (__n / 4) + : "memory", "cc"); +#else + __asm__ __volatile__ + ("1:\tmovl %0,(%1)\n\t" + "leal 4(%1),%1\n\t" + "decl %2\n\t" + "jnz 1b\n" + "movw %w0,(%1)" + : "=&q" (__d0), "=&r" (__tmp), "=&r" (__d1) + : "0" ((unsigned int) __c), "1" (__tmp), "2" (__n / 4) + : "memory", "cc"); +#endif + return __s; +} + +#define __memset_gcn(s, c, n) \ + (((n) % 4 == 0) \ + ? __memset_gcn_by4 (s, c, n) \ + : (((n) % 2 == 0) \ + ? __memset_gcn_by2 (s, c, n) \ + : __memset_gg (s, c, n))) + +__STRING_INLINE void *__memset_gcn_by4 (void *__s, int __c, size_t __n); + +__STRING_INLINE void * +__memset_gcn_by4 (void *__s, int __c, size_t __n) { register void *__tmp = __s; register unsigned long int __d0; @@ -226,17 +359,15 @@ __memset_gc_by4 (void *__s, int __c, size_t __n) return __s; } -__STRING_INLINE void *__memset_gc_by2 (void *__s, int __c, size_t __n); +__STRING_INLINE void *__memset_gcn_by2 (void *__s, int __c, size_t __n); __STRING_INLINE void * -__memset_gc_by2 (void *__s, int __c, size_t __n) +__memset_gcn_by2 (void *__s, int __c, size_t __n) { register unsigned long int __d0, __d1; register void *__tmp = __s; __asm__ __volatile__ ("movb %b0,%h0\n\t" - "shrl $1,%2\n\t" /* may be divisible also by 4 */ - "jz 2f\n\t" "pushw %w0\n\t" "shll $16,%0\n\t" "popw %w0\n" @@ -245,10 +376,9 @@ __memset_gc_by2 (void *__s, int __c, size_t __n) "leal 4(%1),%1\n\t" "decl %2\n\t" "jnz 1b\n" - "2:\n\t" "movw %w0,(%1)" : "=&q" (__d0), "=&r" (__tmp), "=&r" (__d1) - : "0" ((unsigned int) __c), "1" (__tmp), "2" (__n / 2) + : "0" ((unsigned int) __c), "1" (__tmp), "2" (__n / 4) : "memory", "cc"); return __s; } @@ -261,7 +391,8 @@ __memset_gg (void *__s, int __c, size_t __n) register unsigned long int __d0, __d1; register void *__tmp = __s; __asm__ __volatile__ - ("movb %%al,%%ah\n\t" + ("cld\n\t" + "movb %%al,%%ah\n\t" "shrl $1,%%ecx\n\t" "rep; stosw\n\t" "jnc 1f\n\t" @@ -280,18 +411,20 @@ __STRING_INLINE void * memchr (__const void *__s, int __c, size_t __n) { register unsigned long int __d0; +#ifdef __i686__ + register unsigned long int __d1; +#endif register unsigned char *__res; if (__n == 0) return NULL; #ifdef __i686__ __asm__ __volatile__ - ("movl $1, %%edx\n\t" - "cld\n\t" + ("cld\n\t" "repne; scasb\n\t" - "cmovne %%edx,%0" - : "=D" (__res), "=&c" (__d0) - : "a" (__c), "0" (__s), "1" (__n) - : "dx", "cc"); + "cmovne %2,%0" + : "=D" (__res), "=&c" (__d0), "=&r" (__d1) + : "a" (__c), "0" (__s), "1" (__n), "2" (1) + : "cc"); #else __asm__ __volatile__ ("cld\n\t" |