linux/arch/ia64/lib/strnlen_user.S
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

46 lines
903 B
ArmAsm

/*
* Returns 0 if exception before NUL or reaching the supplied limit (N),
* a value greater than N if the string is longer than the limit, else
* strlen.
*
* Inputs:
* in0: address of buffer
* in1: string length limit N
* Outputs:
* r8: 0 in case of fault, strlen(buffer)+1 otherwise
*
* Copyright (C) 1999, 2001 David Mosberger-Tang <davidm@hpl.hp.com>
*/
#include <asm/asmmacro.h>
GLOBAL_ENTRY(__strnlen_user)
.prologue
alloc r2=ar.pfs,2,0,0,0
.save ar.lc, r16
mov r16=ar.lc // preserve ar.lc
.body
add r3=-1,in1
;;
mov ar.lc=r3
mov r9=0
;;
// XXX braindead strlen loop---this needs to be optimized
.Loop1:
EXCLR(.Lexit, ld1 r8=[in0],1)
add r9=1,r9
;;
cmp.eq p6,p0=r8,r0
(p6) br.cond.dpnt .Lexit
br.cloop.dptk.few .Loop1
add r9=1,in1 // NUL not found---return N+1
;;
.Lexit:
mov r8=r9
mov ar.lc=r16 // restore ar.lc
br.ret.sptk.many rp
END(__strnlen_user)