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-rw-r--r--contrib/syslinux-4.02/gpxe/src/arch/x86/include/bits/string.h252
1 files changed, 252 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/gpxe/src/arch/x86/include/bits/string.h b/contrib/syslinux-4.02/gpxe/src/arch/x86/include/bits/string.h
new file mode 100644
index 0000000..a68868a
--- /dev/null
+++ b/contrib/syslinux-4.02/gpxe/src/arch/x86/include/bits/string.h
@@ -0,0 +1,252 @@
+#ifndef ETHERBOOT_BITS_STRING_H
+#define ETHERBOOT_BITS_STRING_H
+/*
+ * Taken from Linux /usr/include/asm/string.h
+ * All except memcpy, memmove, memset and memcmp removed.
+ *
+ * Non-standard memswap() function added because it saves quite a bit
+ * of code (mbrown@fensystems.co.uk).
+ */
+
+/*
+ * 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.
+ */
+
+FILE_LICENCE ( PUBLIC_DOMAIN );
+
+#define __HAVE_ARCH_MEMCPY
+
+extern void * __memcpy ( void *dest, const void *src, size_t len );
+
+#if 0
+static inline __attribute__ (( always_inline )) void *
+__memcpy ( void *dest, const void *src, size_t len ) {
+ int d0, d1, d2;
+ __asm__ __volatile__ ( "rep ; movsb"
+ : "=&c" ( d0 ), "=&S" ( d1 ), "=&D" ( d2 )
+ : "0" ( len ), "1" ( src ), "2" ( dest )
+ : "memory" );
+ return dest;
+}
+#endif
+
+static inline __attribute__ (( always_inline )) void *
+__constant_memcpy ( void *dest, const void *src, size_t len ) {
+ union {
+ uint32_t u32[2];
+ uint16_t u16[4];
+ uint8_t u8[8];
+ } __attribute__ (( __may_alias__ )) *dest_u = dest;
+ const union {
+ uint32_t u32[2];
+ uint16_t u16[4];
+ uint8_t u8[8];
+ } __attribute__ (( __may_alias__ )) *src_u = src;
+ const void *esi;
+ void *edi;
+
+ switch ( len ) {
+ case 0 : /* 0 bytes */
+ return dest;
+ /*
+ * Single-register moves; these are always better than a
+ * string operation. We can clobber an arbitrary two
+ * registers (data, source, dest can re-use source register)
+ * instead of being restricted to esi and edi. There's also a
+ * much greater potential for optimising with nearby code.
+ *
+ */
+ case 1 : /* 4 bytes */
+ dest_u->u8[0] = src_u->u8[0];
+ return dest;
+ case 2 : /* 6 bytes */
+ dest_u->u16[0] = src_u->u16[0];
+ return dest;
+ case 4 : /* 4 bytes */
+ dest_u->u32[0] = src_u->u32[0];
+ return dest;
+ /*
+ * Double-register moves; these are probably still a win.
+ *
+ */
+ case 3 : /* 12 bytes */
+ dest_u->u16[0] = src_u->u16[0];
+ dest_u->u8[2] = src_u->u8[2];
+ return dest;
+ case 5 : /* 10 bytes */
+ dest_u->u32[0] = src_u->u32[0];
+ dest_u->u8[4] = src_u->u8[4];
+ return dest;
+ case 6 : /* 12 bytes */
+ dest_u->u32[0] = src_u->u32[0];
+ dest_u->u16[2] = src_u->u16[2];
+ return dest;
+ case 8 : /* 10 bytes */
+ dest_u->u32[0] = src_u->u32[0];
+ dest_u->u32[1] = src_u->u32[1];
+ return dest;
+ }
+
+ /* Even if we have to load up esi and edi ready for a string
+ * operation, we can sometimes save space by using multiple
+ * single-byte "movs" operations instead of loading up ecx and
+ * using "rep movsb".
+ *
+ * "load ecx, rep movsb" is 7 bytes, plus an average of 1 byte
+ * to allow for saving/restoring ecx 50% of the time.
+ *
+ * "movsl" and "movsb" are 1 byte each, "movsw" is two bytes.
+ * (In 16-bit mode, "movsl" is 2 bytes and "movsw" is 1 byte,
+ * but "movsl" moves twice as much data, so it balances out).
+ *
+ * The cutoff point therefore occurs around 26 bytes; the byte
+ * requirements for each method are:
+ *
+ * len 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
+ * #bytes (ecx) 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8
+ * #bytes (no ecx) 4 5 6 7 5 6 7 8 6 7 8 9 7 8 9 10
+ */
+
+ esi = src;
+ edi = dest;
+
+ if ( len >= 26 )
+ return __memcpy ( dest, src, len );
+
+ if ( len >= 6*4 )
+ __asm__ __volatile__ ( "movsl" : "=&D" ( edi ), "=&S" ( esi )
+ : "0" ( edi ), "1" ( esi ) : "memory" );
+ if ( len >= 5*4 )
+ __asm__ __volatile__ ( "movsl" : "=&D" ( edi ), "=&S" ( esi )
+ : "0" ( edi ), "1" ( esi ) : "memory" );
+ if ( len >= 4*4 )
+ __asm__ __volatile__ ( "movsl" : "=&D" ( edi ), "=&S" ( esi )
+ : "0" ( edi ), "1" ( esi ) : "memory" );
+ if ( len >= 3*4 )
+ __asm__ __volatile__ ( "movsl" : "=&D" ( edi ), "=&S" ( esi )
+ : "0" ( edi ), "1" ( esi ) : "memory" );
+ if ( len >= 2*4 )
+ __asm__ __volatile__ ( "movsl" : "=&D" ( edi ), "=&S" ( esi )
+ : "0" ( edi ), "1" ( esi ) : "memory" );
+ if ( len >= 1*4 )
+ __asm__ __volatile__ ( "movsl" : "=&D" ( edi ), "=&S" ( esi )
+ : "0" ( edi ), "1" ( esi ) : "memory" );
+ if ( ( len % 4 ) >= 2 )
+ __asm__ __volatile__ ( "movsw" : "=&D" ( edi ), "=&S" ( esi )
+ : "0" ( edi ), "1" ( esi ) : "memory" );
+ if ( ( len % 2 ) >= 1 )
+ __asm__ __volatile__ ( "movsb" : "=&D" ( edi ), "=&S" ( esi )
+ : "0" ( edi ), "1" ( esi ) : "memory" );
+
+ return dest;
+}
+
+#define memcpy( dest, src, len ) \
+ ( __builtin_constant_p ( (len) ) ? \
+ __constant_memcpy ( (dest), (src), (len) ) : \
+ __memcpy ( (dest), (src), (len) ) )
+
+#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 __HAVE_ARCH_MEMSET
+static inline void * memset(void *s, int 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;
+}
+
+#define __HAVE_ARCH_MEMSWAP
+static inline void * memswap(void *dest, void *src, size_t n)
+{
+int d0, d1, d2, d3;
+__asm__ __volatile__(
+ "\n1:\t"
+ "movb (%%edi),%%al\n\t"
+ "xchgb (%%esi),%%al\n\t"
+ "incl %%esi\n\t"
+ "stosb\n\t"
+ "loop 1b"
+ : "=&c" (d0), "=&S" (d1), "=&D" (d2), "=&a" (d3)
+ : "0" (n), "1" (src), "2" (dest)
+ : "memory" );
+return dest;
+}
+
+#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__(
+ "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_STRLEN
+static inline size_t strlen(const char * s)
+{
+int d0;
+register int __res;
+__asm__ __volatile__(
+ "repne\n\t"
+ "scasb\n\t"
+ "notl %0\n\t"
+ "decl %0"
+ :"=c" (__res), "=&D" (d0) :"1" (s),"a" (0), "0" (0xffffffff));
+return __res;
+}
+
+#endif /* ETHERBOOT_BITS_STRING_H */
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