/* $OpenBSD: strcat.S,v 1.8 2005/08/07 11:30:38 espie Exp $ */ /* * Written by J.T. Conklin . * Public domain. */ #include #if defined(APIWARN) #APP .section .gnu.warning.strcat .ascii "warning: strcat() is almost always misused, please use strlcat()" #NO_APP #endif /* * NOTE: I've unrolled the loop eight times: large enough to make a * significant difference, and small enough not to totally trash the * cache. */ ENTRY(strcat) pushl %edi /* save edi */ movl 8(%esp),%edi /* dst address */ movl 12(%esp),%edx /* src address */ pushl %edi /* push destination address */ cld /* set search forward */ xorl %eax,%eax /* set search for null terminator */ movl $-1,%ecx /* set search for lots of characters */ repne /* search! */ scasb leal -1(%edi),%ecx /* correct dst address */ .align 2,0x90 L1: movb (%edx),%al /* unroll loop, but not too much */ movb %al,(%ecx) testb %al,%al jz L2 movb 1(%edx),%al movb %al,1(%ecx) testb %al,%al jz L2 movb 2(%edx),%al movb %al,2(%ecx) testb %al,%al jz L2 movb 3(%edx),%al movb %al,3(%ecx) testb %al,%al jz L2 movb 4(%edx),%al movb %al,4(%ecx) testb %al,%al jz L2 movb 5(%edx),%al movb %al,5(%ecx) testb %al,%al jz L2 movb 6(%edx),%al movb %al,6(%ecx) testb %al,%al jz L2 movb 7(%edx),%al movb %al,7(%ecx) addl $8,%edx addl $8,%ecx testb %al,%al jnz L1 L2: popl %eax /* pop destination address */ popl %edi /* restore edi */ ret