77 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
			
		
		
	
	
			77 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
| /*
 | |
| Copyright (c) 2013 Andes Technology Corporation.
 | |
| All rights reserved.
 | |
| 
 | |
| Redistribution and use in source and binary forms, with or without
 | |
| modification, are permitted provided that the following conditions are met:
 | |
| 
 | |
|     Redistributions of source code must retain the above copyright
 | |
|     notice, this list of conditions and the following disclaimer.
 | |
| 
 | |
|     Redistributions in binary form must reproduce the above copyright
 | |
|     notice, this list of conditions and the following disclaimer in the
 | |
|     documentation and/or other materials provided with the distribution.
 | |
| 
 | |
|     The name of the company may not be used to endorse or promote
 | |
|     products derived from this software without specific prior written
 | |
|     permission.
 | |
| 
 | |
| THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 | |
| AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 | |
| IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 | |
| DISCLAIMED.  IN NO EVENT SHALL RED HAT INCORPORATED BE LIABLE FOR ANY
 | |
| DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 | |
| (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 | |
| LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 | |
| ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 | |
| (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 | |
| SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 | |
| 
 | |
| 
 | |
|     Function:
 | |
|        strcpy - copy a string.
 | |
|     Syntax:
 | |
|        char *strcpy(char *dest, const char *src);
 | |
|     Description:
 | |
|        This function copies the string pointed to by src into the array
 | |
|        point to by dest (include the teminating null character).
 | |
|     Return value:
 | |
|        strcpy returns the dest as given.
 | |
| */
 | |
| 	.text
 | |
| 	.align	2
 | |
| 	.globl	strcpy
 | |
| 	.type	strcpy, @function
 | |
| strcpy:
 | |
| 	move	$r3, $r0	/* Keep r0 as reture value.  */
 | |
| 	/* If SRC or DEST is unaligned, then copy bytes.  */
 | |
| 	or	$r2, $r1, $r0
 | |
| 	andi	$r2, $r2, #3
 | |
| 	bnez	$r2, .Lbyte_mode
 | |
| 
 | |
| .Lword_mode:
 | |
| 	/* SRC and DEST are both "long int" aligned, try to do "long int"
 | |
| 	   sized copies.  */
 | |
| 	/* #define DETECTNULL(X) (((X) - 0x01010101) & ~(X) & 0x80808080)
 | |
| 	   DETECTNULL returns nonzero if (long)X contains a NULL byte.  */
 | |
| 	lwi	$r2, [$r1+(0)]		/* r2 is X */
 | |
| 	sethi	$r4, hi20(0xFEFEFEFF)
 | |
| 	ori	$r4, $r4, lo12(0xFEFEFEFF)
 | |
| 	add	$r4, $r2, $r4		/* r4 = ((X) - 0x01010101) */
 | |
| 	nor	$r5, $r2, $r2		/* r5 = ~(X) */
 | |
| 	and	$r4, $r5, $r4		/* r4 = ~(X) & ((X) - 0x01010101) */
 | |
| 	sethi	$r5, hi20(0x80808080)
 | |
| 	ori	$r5, $r5, lo12(0x80808080)
 | |
| 	and	$r4, $r4, $r5		/* r4 = r4 & 0x80808080 */
 | |
| 	bnez	$r4, .Lbyte_mode	/* Contains a NULL byte.  */
 | |
| 	swi.bi	$r2, [$r3], #4
 | |
| 	addi	$r1, $r1, #4
 | |
| 	b	.Lword_mode
 | |
| 
 | |
| .Lbyte_mode:
 | |
| 	lbi.bi	$r4, [$r1], #1		/* r4  <- *src++ */
 | |
| 	sbi.bi	$r4, [$r3], #1		/* r4  -> *dest++ */
 | |
| 	bnez	$r4, .Lbyte_mode
 | |
| 	ret
 | |
| 	.size	strcpy, .-strcpy
 |