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author | Pasha <pasha@member.fsf.org> | 2024-02-20 18:49:50 +0000 |
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committer | Pasha <pasha@member.fsf.org> | 2024-02-20 18:49:50 +0000 |
commit | 5e0b8d508ed51004bd836384293be00950ee62c9 (patch) | |
tree | e3f16b1aa8b7177032ce3ec429fbad2b1d92a876 /linux/dev/include/asm-i386/string.h | |
download | gnumach-riscv-5e0b8d508ed51004bd836384293be00950ee62c9.tar.gz gnumach-riscv-5e0b8d508ed51004bd836384293be00950ee62c9.tar.bz2 |
init gnumach copy
Diffstat (limited to 'linux/dev/include/asm-i386/string.h')
-rw-r--r-- | linux/dev/include/asm-i386/string.h | 487 |
1 files changed, 487 insertions, 0 deletions
diff --git a/linux/dev/include/asm-i386/string.h b/linux/dev/include/asm-i386/string.h new file mode 100644 index 0000000..f41ca5c --- /dev/null +++ b/linux/dev/include/asm-i386/string.h @@ -0,0 +1,487 @@ +#ifndef _I386_STRING_H_ +#define _I386_STRING_H_ + +/* + * On a 486 or Pentium, we are better off not using the + * byte string operations. But on a 386 or a PPro the + * byte string ops are faster than doing it by hand + * (MUCH faster on a Pentium). + * + * Also, the byte strings actually work correctly. Forget + * the i486 routines for now as they may be broken.. + */ +#if FIXED_486_STRING && (CPU == 486 || CPU == 586) +#include <asm/string-486.h> +#else + +/* + * This string-include defines all string functions as inline + * functions. Use gcc. It also assumes ds=es=data space, this should be + * normal. Most of the string-functions are rather heavily hand-optimized, + * see especially strtok,strstr,str[c]spn. They should work, but are not + * very easy to understand. Everything is done entirely within the register + * set, making the functions fast and clean. String instructions have been + * used through-out, making for "slightly" unclear code :-) + * + * NO Copyright (C) 1991, 1992 Linus Torvalds, + * consider these trivial functions to be PD. + */ + +#define __HAVE_ARCH_STRCPY +static inline char * strcpy(char * dest,const char *src) +{ +int d0, d1, d2; +__asm__ __volatile__( + "cld\n" + "1:\tlodsb\n\t" + "stosb\n\t" + "testb %%al,%%al\n\t" + "jne 1b" + : "=&S" (d0), "=&D" (d1), "=&a" (d2) + :"0" (src),"1" (dest) : "memory"); +return dest; +} + +#define __HAVE_ARCH_STRNCPY +static inline char * strncpy(char * dest,const char *src,size_t count) +{ +int d0, d1, d2, d3; +__asm__ __volatile__( + "cld\n" + "1:\tdecl %2\n\t" + "js 2f\n\t" + "lodsb\n\t" + "stosb\n\t" + "testb %%al,%%al\n\t" + "jne 1b\n\t" + "rep\n\t" + "stosb\n" + "2:" + : "=&S" (d0), "=&D" (d1), "=&c" (d2), "=&a" (d3) + :"0" (src),"1" (dest),"2" (count) : "memory"); +return dest; +} + +#define __HAVE_ARCH_STRCAT +static inline char * strcat(char * dest,const char * src) +{ +int d0, d1, d2, d3; +__asm__ __volatile__( + "cld\n\t" + "repne\n\t" + "scasb\n\t" + "decl %1\n" + "1:\tlodsb\n\t" + "stosb\n\t" + "testb %%al,%%al\n\t" + "jne 1b" + : "=&S" (d0), "=&D" (d1), "=&a" (d2), "=&c" (d3) + : "0" (src), "1" (dest), "2" (0), "3" (0xffffffff):"memory"); +return dest; +} + +#define __HAVE_ARCH_STRNCAT +static inline char * strncat(char * dest,const char * src,size_t count) +{ +int d0, d1, d2, d3; +__asm__ __volatile__( + "cld\n\t" + "repne\n\t" + "scasb\n\t" + "decl %1\n\t" + "movl %8,%3\n" + "1:\tdecl %3\n\t" + "js 2f\n\t" + "lodsb\n\t" + "stosb\n\t" + "testb %%al,%%al\n\t" + "jne 1b\n" + "2:\txorl %2,%2\n\t" + "stosb" + : "=&S" (d0), "=&D" (d1), "=&a" (d2), "=&c" (d3) + : "0" (src),"1" (dest),"2" (0),"3" (0xffffffff), "g" (count) + : "memory"); +return dest; +} + +#define __HAVE_ARCH_STRCMP +static inline int strcmp(const char * cs,const char * ct) +{ +int d0, d1; +register int __res; +__asm__ __volatile__( + "cld\n" + "1:\tlodsb\n\t" + "scasb\n\t" + "jne 2f\n\t" + "testb %%al,%%al\n\t" + "jne 1b\n\t" + "xorl %%eax,%%eax\n\t" + "jmp 3f\n" + "2:\tsbbl %%eax,%%eax\n\t" + "orb $1,%%al\n" + "3:" + :"=a" (__res), "=&S" (d0), "=&D" (d1) + :"1" (cs),"2" (ct)); +return __res; +} + +#define __HAVE_ARCH_STRNCMP +static inline int strncmp(const char * cs,const char * ct,size_t count) +{ +register int __res; +int d0, d1, d2; +__asm__ __volatile__( + "cld\n" + "1:\tdecl %3\n\t" + "js 2f\n\t" + "lodsb\n\t" + "scasb\n\t" + "jne 3f\n\t" + "testb %%al,%%al\n\t" + "jne 1b\n" + "2:\txorl %%eax,%%eax\n\t" + "jmp 4f\n" + "3:\tsbbl %%eax,%%eax\n\t" + "orb $1,%%al\n" + "4:" + :"=a" (__res), "=&S" (d0), "=&D" (d1), "=&c" (d2) + :"1" (cs),"2" (ct),"3" (count)); +return __res; +} + +#define __HAVE_ARCH_STRCHR +static inline char * strchr(const char * s, int c) +{ +int d0; +register char * __res; +__asm__ __volatile__( + "cld\n\t" + "movb %%al,%%ah\n" + "1:\tlodsb\n\t" + "cmpb %%ah,%%al\n\t" + "je 2f\n\t" + "testb %%al,%%al\n\t" + "jne 1b\n\t" + "movl $1,%1\n" + "2:\tmovl %1,%0\n\t" + "decl %0" + :"=a" (__res), "=&S" (d0) : "1" (s),"0" (c)); +return __res; +} + +#define __HAVE_ARCH_STRRCHR +static inline char * strrchr(const char * s, int c) +{ +int d0, d1; +register char * __res; +__asm__ __volatile__( + "cld\n\t" + "movb %%al,%%ah\n" + "1:\tlodsb\n\t" + "cmpb %%ah,%%al\n\t" + "jne 2f\n\t" + "leal -1(%%esi),%0\n" + "2:\ttestb %%al,%%al\n\t" + "jne 1b" + :"=g" (__res), "=&S" (d0), "=&a" (d1) :"0" (0),"1" (s),"2" (c)); +return __res; +} + +#define __HAVE_ARCH_STRLEN +static inline size_t strlen(const char * s) +{ +int d0; +register int __res; +__asm__ __volatile__( + "cld\n\t" + "repne\n\t" + "scasb\n\t" + "notl %0\n\t" + "decl %0" + :"=c" (__res), "=&D" (d0) :"1" (s),"a" (0), "0" (0xffffffff)); +return __res; +} + +static inline void * __memcpy(void * to, const void * from, size_t n) +{ +int d0, d1, d2; +__asm__ __volatile__( + "cld\n\t" + "rep ; movsl\n\t" + "testb $2,%b4\n\t" + "je 1f\n\t" + "movsw\n" + "1:\ttestb $1,%b4\n\t" + "je 2f\n\t" + "movsb\n" + "2:" + : "=&c" (d0), "=&D" (d1), "=&S" (d2) + :"0" (n/4), "q" (n),"1" ((long) to),"2" ((long) from) + : "memory"); +return (to); +} + +/* + * This looks horribly ugly, but the compiler can optimize it totally, + * as the count is constant. + */ +static inline void * __constant_memcpy(void * to, const void * from, size_t n) +{ + switch (n) { + case 0: + return to; + case 1: + *(unsigned char *)to = *(const unsigned char *)from; + return to; + case 2: + *(unsigned short *)to = *(const unsigned short *)from; + return to; + case 3: + *(unsigned short *)to = *(const unsigned short *)from; + *(2+(unsigned char *)to) = *(2+(const unsigned char *)from); + return to; + case 4: + *(unsigned long *)to = *(const unsigned long *)from; + return to; + case 6: /* for Ethernet addresses */ + *(unsigned long *)to = *(const unsigned long *)from; + *(2+(unsigned short *)to) = *(2+(const unsigned short *)from); + return to; + case 8: + *(unsigned long *)to = *(const unsigned long *)from; + *(1+(unsigned long *)to) = *(1+(const unsigned long *)from); + return to; + case 12: + *(unsigned long *)to = *(const unsigned long *)from; + *(1+(unsigned long *)to) = *(1+(const unsigned long *)from); + *(2+(unsigned long *)to) = *(2+(const unsigned long *)from); + return to; + case 16: + *(unsigned long *)to = *(const unsigned long *)from; + *(1+(unsigned long *)to) = *(1+(const unsigned long *)from); + *(2+(unsigned long *)to) = *(2+(const unsigned long *)from); + *(3+(unsigned long *)to) = *(3+(const unsigned long *)from); + return to; + case 20: + *(unsigned long *)to = *(const unsigned long *)from; + *(1+(unsigned long *)to) = *(1+(const unsigned long *)from); + *(2+(unsigned long *)to) = *(2+(const unsigned long *)from); + *(3+(unsigned long *)to) = *(3+(const unsigned long *)from); + *(4+(unsigned long *)to) = *(4+(const unsigned long *)from); + return to; + } +#define COMMON(x) \ +__asm__ __volatile__( \ + "cld\n\t" \ + "rep ; movsl" \ + x \ + : "=&c" (d0), "=&D" (d1), "=&S" (d2) \ + : "0" (n/4),"1" ((long) to),"2" ((long) from) \ + : "memory"); +{ + int d0, d1, d2; + switch (n % 4) { + case 0: COMMON(""); return to; + case 1: COMMON("\n\tmovsb"); return to; + case 2: COMMON("\n\tmovsw"); return to; + default: COMMON("\n\tmovsw\n\tmovsb"); return to; + } +} + +#undef COMMON +} + +#define __HAVE_ARCH_MEMCPY +#define memcpy(t, f, n) \ +(__builtin_constant_p(n) ? \ + __constant_memcpy((t),(f),(n)) : \ + __memcpy((t),(f),(n))) + +#define __HAVE_ARCH_MEMMOVE +static inline void * memmove(void * dest,const void * src, size_t n) +{ +int d0, d1, d2; +if (dest<src) +__asm__ __volatile__( + "cld\n\t" + "rep\n\t" + "movsb" + : "=&c" (d0), "=&S" (d1), "=&D" (d2) + :"0" (n),"1" (src),"2" (dest) + : "memory"); +else +__asm__ __volatile__( + "std\n\t" + "rep\n\t" + "movsb\n\t" + "cld" + : "=&c" (d0), "=&S" (d1), "=&D" (d2) + :"0" (n), + "1" (n-1+(const char *)src), + "2" (n-1+(char *)dest) + :"memory"); +return dest; +} + +#define memcmp __builtin_memcmp + +#define __HAVE_ARCH_MEMCHR +static inline void * memchr(const void * cs,int c,size_t count) +{ +int d0; +register void * __res; +if (!count) + return NULL; +__asm__ __volatile__( + "cld\n\t" + "repne\n\t" + "scasb\n\t" + "je 1f\n\t" + "movl $1,%0\n" + "1:\tdecl %0" + :"=D" (__res), "=&c" (d0) : "a" (c),"0" (cs),"1" (count)); +return __res; +} + +static inline void * __memset_generic(void * s, char c,size_t count) +{ +int d0, d1; +__asm__ __volatile__( + "cld\n\t" + "rep\n\t" + "stosb" + : "=&c" (d0), "=&D" (d1) + :"a" (c),"1" (s),"0" (count) + :"memory"); +return s; +} + +/* we might want to write optimized versions of these later */ +#define __constant_count_memset(s,c,count) __memset_generic((s),(c),(count)) + +/* + * memset(x,0,y) is a reasonably common thing to do, so we want to fill + * things 32 bits at a time even when we don't know the size of the + * area at compile-time.. + */ +static inline void * __constant_c_memset(void * s, unsigned long c, size_t count) +{ +int d0, d1; +__asm__ __volatile__( + "cld\n\t" + "rep ; stosl\n\t" + "testb $2,%b3\n\t" + "je 1f\n\t" + "stosw\n" + "1:\ttestb $1,%b3\n\t" + "je 2f\n\t" + "stosb\n" + "2:" + : "=&c" (d0), "=&D" (d1) + :"a" (c), "q" (count), "0" (count/4), "1" ((long) s) + :"memory"); +return (s); +} + +/* Added by Gertjan van Wingerde to make minix and sysv module work */ +#define __HAVE_ARCH_STRNLEN +static inline size_t strnlen(const char * s, size_t count) +{ +int d0; +register int __res; +__asm__ __volatile__( + "movl %2,%0\n\t" + "jmp 2f\n" + "1:\tcmpb $0,(%0)\n\t" + "je 3f\n\t" + "incl %0\n" + "2:\tdecl %1\n\t" + "cmpl $-1,%1\n\t" + "jne 1b\n" + "3:\tsubl %2,%0" + :"=a" (__res), "=&d" (d0) + :"c" (s),"1" (count)); +return __res; +} +/* end of additional stuff */ + +/* + * This looks horribly ugly, but the compiler can optimize it totally, + * as we by now know that both pattern and count is constant.. + */ +static inline void * __constant_c_and_count_memset(void * s, unsigned long pattern, size_t count) +{ + switch (count) { + case 0: + return s; + case 1: + *(unsigned char *)s = pattern; + return s; + case 2: + *(unsigned short *)s = pattern; + return s; + case 3: + *(unsigned short *)s = pattern; + *(2+(unsigned char *)s) = pattern; + return s; + case 4: + *(unsigned long *)s = pattern; + return s; + } +#define COMMON(x) \ +__asm__ __volatile__("cld\n\t" \ + "rep ; stosl" \ + x \ + : "=&c" (d0), "=&D" (d1) \ + : "a" (pattern),"0" (count/4),"1" ((long) s) \ + : "memory") +{ + int d0, d1; + switch (count % 4) { + case 0: COMMON(""); return s; + case 1: COMMON("\n\tstosb"); return s; + case 2: COMMON("\n\tstosw"); return s; + default: COMMON("\n\tstosw\n\tstosb"); return s; + } +} + +#undef COMMON +} + +#define __constant_c_x_memset(s, c, count) \ +(__builtin_constant_p(count) ? \ + __constant_c_and_count_memset((s),(c),(count)) : \ + __constant_c_memset((s),(c),(count))) + +#define __memset(s, c, count) \ +(__builtin_constant_p(count) ? \ + __constant_count_memset((s),(c),(count)) : \ + __memset_generic((s),(c),(count))) + +#define __HAVE_ARCH_MEMSET +#define memset(s, c, count) \ +(__builtin_constant_p(c) ? \ + __constant_c_x_memset((s),(0x01010101UL*(unsigned char)(c)),(count)) : \ + __memset((s),(c),(count))) + +/* + * find the first occurrence of byte 'c', or 1 past the area if none + */ +#define __HAVE_ARCH_MEMSCAN +static inline void * memscan(void * addr, int c, size_t size) +{ + if (!size) + return addr; + __asm__("cld\n" + "repnz; scasb\n" + "jnz 1f\n" + "dec %%edi\n" + "1:\n" + : "=D" (addr), "=c" (size) + : "0" (addr), "1" (size), "a" (c)); + return addr; +} + +#endif +#endif |