diff options
Diffstat (limited to 'arch/ia64/lib/strnlen_user.S')
| -rw-r--r-- | arch/ia64/lib/strnlen_user.S | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/arch/ia64/lib/strnlen_user.S b/arch/ia64/lib/strnlen_user.S new file mode 100644 index 0000000000..a7eb56e840 --- /dev/null +++ b/arch/ia64/lib/strnlen_user.S @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * 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 <linux/export.h> +#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) +EXPORT_SYMBOL(__strnlen_user) |