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/* Project: OSLib
* Description: The OS Construction Kit
* Date: 1.6.2000
* Idea by: Luca Abeni & Gerardo Lamastra
*
* OSLib is an SO project aimed at developing a common, easy-to-use
* low-level infrastructure for developing OS kernels and Embedded
* Applications; it partially derives from the HARTIK project but it
* currently is independently developed.
*
* OSLib is distributed under GPL License, and some of its code has
* been derived from the Linux kernel source; also some important
* ideas come from studying the DJGPP go32 extender.
*
* We acknowledge the Linux Community, Free Software Foundation,
* D.J. Delorie and all the other developers who believe in the
* freedom of software and ideas.
*
* For legalese, check out the included GPL license.
*/
/* Memory manipulation functions...
Some of them are derived from Linux */
#ifndef __LL_I386_MEM_H__
#define __LL_I386_MEM_H__
#include <ll/i386/defs.h>
BEGIN_DEF
/* Various string manipulation functions */
/* Assembler low level routines */
/* File: Mem.S */
#ifndef NULL
#define NULL 0L
#endif
#include <ll/sys/types.h>
#include <ll/i386/hw-data.h>
/*
#ifndef __HW_DEP_H__
#include "hw_dep.h"
#endif
*/
extern 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.
*/
extern 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)))
extern inline void *lmemcpy(LIN_ADDR t, LIN_ADDR f, size_t n)
{
void *p1;
void *p2;
p1 = (void *)(t);
p2 = (void *)(f);
return memcpy(p1, p2, n);
}
#define __HAVE_ARCH_MEMMOVE
extern 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
extern 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;
}
extern 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..
*/
extern 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);
}
/*
* This looks horribly ugly, but the compiler can optimize it totally,
* as we by now know that both pattern and count is constant..
*/
extern 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
extern inline void * memscan(void * addr, int c, size_t size)
{
if (!size)
return addr;
__asm__("cld
repnz; scasb
jnz 1f
dec %%edi
1: "
: "=D" (addr), "=c" (size)
: "0" (addr), "1" (size), "a" (c));
return addr;
}
void fmemcpy(unsigned short ds,unsigned long dof,unsigned short ss,unsigned long sof,unsigned n);
#if 0
extern inline void fmemcpy(unsigned short ds,unsigned long dof,unsigned short ss,unsigned long sof,unsigned n)
{
/* Build the standard stack frame */
__asm__ __volatile__(
/* Get parms into register */
movl 8(%ebp),%eax
movw %ax,%es
movl 12(%ebp),%edi
movl 16(%ebp),%eax
movw %ax,%ds
movl 20(%ebp),%esi
movl 24(%ebp),%ecx
cld
rep
"movsb"
"2:"
: "=&c" (d0), "=&D" (d1), "=&S" (d2)
:"0" (n), "q" (n),"1" ((long) to),"2" ((long) from)
: "memory");
);
popw %es
popw %ds
popl %edi
popl %esi
leave
ret
#endif
END_DEF
#endif