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Ignore whitespace Rev 3043 → Rev 3044

/trunk/kernel/arch/amd64/include/memstr.h
35,110 → 35,13
#ifndef KERN_amd64_MEMSTR_H_
#define KERN_amd64_MEMSTR_H_
 
/** Copy memory
*
* Copy a given number of bytes (3rd argument)
* from the memory location defined by 2nd argument
* to the memory location defined by 1st argument.
* The memory areas cannot overlap.
*
* @param dst Destination
* @param src Source
* @param cnt Number of bytes
* @return Destination
*/
static inline void * memcpy(void * dst, const void * src, size_t cnt)
{
unative_t d0, d1, d2;
#define memcpy(dst, src, cnt) __builtin_memcpy((dst), (src), (cnt))
 
asm volatile(
"rep movsq\n\t"
"movq %4, %%rcx\n\t"
"andq $7, %%rcx\n\t"
"jz 1f\n\t"
"rep movsb\n\t"
"1:\n"
: "=&c" (d0), "=&D" (d1), "=&S" (d2)
: "0" ((unative_t)(cnt / 8)), "g" ((unative_t)cnt), "1" ((unative_t) dst), "2" ((unative_t) src)
: "memory");
extern void memsetw(uintptr_t dst, size_t cnt, uint16_t x);
extern void memsetb(uintptr_t dst, size_t cnt, uint8_t x);
 
return dst;
}
extern int memcmp(uintptr_t src, uintptr_t dst, int cnt);
 
 
/** Compare memory regions for equality
*
* Compare a given number of bytes (3rd argument)
* at memory locations defined by 1st and 2nd argument
* for equality. If bytes are equal function returns 0.
*
* @param src Region 1
* @param dst Region 2
* @param cnt Number of bytes
* @return Zero if bytes are equal, non-zero otherwise
*/
static inline int memcmp(const void * src, const void * dst, size_t cnt)
{
unative_t d0, d1, d2;
unative_t ret;
asm (
"repe cmpsb\n\t"
"je 1f\n\t"
"movq %3, %0\n\t"
"addq $1, %0\n\t"
"1:\n"
: "=a" (ret), "=&S" (d0), "=&D" (d1), "=&c" (d2)
: "0" (0), "1" (src), "2" (dst), "3" ((unative_t)cnt)
);
return ret;
}
 
/** Fill memory with words
* Fill a given number of words (2nd argument)
* at memory defined by 1st argument with the
* word value defined by 3rd argument.
*
* @param dst Destination
* @param cnt Number of words
* @param x Value to fill
*/
static inline void memsetw(uintptr_t dst, size_t cnt, uint16_t x)
{
unative_t d0, d1;
asm volatile (
"rep stosw\n\t"
: "=&D" (d0), "=&c" (d1), "=&a" (x)
: "0" (dst), "1" ((unative_t)cnt), "2" (x)
: "memory"
);
 
}
 
/** Fill memory with bytes
* Fill a given number of bytes (2nd argument)
* at memory defined by 1st argument with the
* word value defined by 3rd argument.
*
* @param dst Destination
* @param cnt Number of bytes
* @param x Value to fill
*/
static inline void memsetb(uintptr_t dst, size_t cnt, uint8_t x)
{
unative_t d0, d1;
asm volatile (
"rep stosb\n\t"
: "=&D" (d0), "=&c" (d1), "=&a" (x)
: "0" (dst), "1" ((unative_t)cnt), "2" (x)
: "memory"
);
 
}
 
#endif
 
/** @}
/trunk/kernel/arch/amd64/src/asm_utils.S
65,6 → 65,8
.global get_cycle
.global read_efer_flag
.global set_efer_flag
.global memsetb
.global memsetw
.global memcpy
.global memcpy_from_uspace
.global memcpy_to_uspace
71,6 → 73,14
.global memcpy_from_uspace_failover_address
.global memcpy_to_uspace_failover_address
 
# Wrapper for generic memsetb
memsetb:
jmp _memsetb
 
# Wrapper for generic memsetw
memsetw:
jmp _memsetw
 
#define MEMCPY_DST %rdi
#define MEMCPY_SRC %rsi
#define MEMCPY_SIZE %rdx