forked from len0rd/rockbox
Move optimized memcpy and friends and strlen to firmware/asm,
using the new automatic-asm-picking infrastructure.
This commit is contained in:
parent
8e8e978de6
commit
a035261089
22 changed files with 7 additions and 34 deletions
110
firmware/asm/memset.c
Normal file
110
firmware/asm/memset.c
Normal file
|
|
@ -0,0 +1,110 @@
|
|||
/*
|
||||
FUNCTION
|
||||
<<memset>>---set an area of memory
|
||||
|
||||
INDEX
|
||||
memset
|
||||
|
||||
ANSI_SYNOPSIS
|
||||
#include <string.h>
|
||||
void *memset(const void *<[dst]>, int <[c]>, size_t <[length]>);
|
||||
|
||||
TRAD_SYNOPSIS
|
||||
#include <string.h>
|
||||
void *memset(<[dst]>, <[c]>, <[length]>)
|
||||
void *<[dst]>;
|
||||
int <[c]>;
|
||||
size_t <[length]>;
|
||||
|
||||
DESCRIPTION
|
||||
This function converts the argument <[c]> into an unsigned
|
||||
char and fills the first <[length]> characters of the array
|
||||
pointed to by <[dst]> to the value.
|
||||
|
||||
RETURNS
|
||||
<<memset>> returns the value of <[m]>.
|
||||
|
||||
PORTABILITY
|
||||
<<memset>> is ANSI C.
|
||||
|
||||
<<memset>> requires no supporting OS subroutines.
|
||||
|
||||
QUICKREF
|
||||
memset ansi pure
|
||||
*/
|
||||
|
||||
#include <string.h>
|
||||
#include "_ansi.h"
|
||||
|
||||
#define LBLOCKSIZE (sizeof(long))
|
||||
#define UNALIGNED(X) ((long)X & (LBLOCKSIZE - 1))
|
||||
#define TOO_SMALL(LEN) ((LEN) < LBLOCKSIZE)
|
||||
|
||||
_PTR
|
||||
_DEFUN (memset, (m, c, n),
|
||||
_PTR m _AND
|
||||
int c _AND
|
||||
size_t n)
|
||||
{
|
||||
#if defined(PREFER_SIZE_OVER_SPEED) || defined(__OPTIMIZE_SIZE__)
|
||||
char *s = (char *) m;
|
||||
|
||||
while (n-- != 0)
|
||||
{
|
||||
*s++ = (char) c;
|
||||
}
|
||||
|
||||
return m;
|
||||
#else
|
||||
char *s = (char *) m;
|
||||
unsigned int i;
|
||||
unsigned long buffer;
|
||||
unsigned long *aligned_addr;
|
||||
|
||||
if (!TOO_SMALL (n) && !UNALIGNED (m))
|
||||
{
|
||||
/* If we get this far, we know that n is large and m is word-aligned. */
|
||||
|
||||
aligned_addr = (unsigned long*)m;
|
||||
|
||||
/* Store C into each char sized location in BUFFER so that
|
||||
we can set large blocks quickly. */
|
||||
c &= 0xff;
|
||||
if (LBLOCKSIZE == 4)
|
||||
{
|
||||
buffer = (c << 8) | c;
|
||||
buffer |= (buffer << 16);
|
||||
}
|
||||
else
|
||||
{
|
||||
buffer = 0;
|
||||
for (i = 0; i < LBLOCKSIZE; i++)
|
||||
buffer = (buffer << 8) | c;
|
||||
}
|
||||
|
||||
while (n >= LBLOCKSIZE*4)
|
||||
{
|
||||
*aligned_addr++ = buffer;
|
||||
*aligned_addr++ = buffer;
|
||||
*aligned_addr++ = buffer;
|
||||
*aligned_addr++ = buffer;
|
||||
n -= 4*LBLOCKSIZE;
|
||||
}
|
||||
|
||||
while (n >= LBLOCKSIZE)
|
||||
{
|
||||
*aligned_addr++ = buffer;
|
||||
n -= LBLOCKSIZE;
|
||||
}
|
||||
/* Pick up the remainder with a bytewise loop. */
|
||||
s = (char*)aligned_addr;
|
||||
}
|
||||
|
||||
while (n--)
|
||||
{
|
||||
*s++ = (char)c;
|
||||
}
|
||||
|
||||
return m;
|
||||
#endif /* not PREFER_SIZE_OVER_SPEED */
|
||||
}
|
||||
Loading…
Add table
Add a link
Reference in a new issue