diff options
Diffstat (limited to 'src/strlen.S')
-rw-r--r-- | src/strlen.S | 61 |
1 files changed, 0 insertions, 61 deletions
diff --git a/src/strlen.S b/src/strlen.S deleted file mode 100644 index 1faf7e2..0000000 --- a/src/strlen.S +++ /dev/null @@ -1,61 +0,0 @@ -/* Copyright (C) 1998 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Code contributed by Matthew Wilcox <willy@odie.barnet.ac.uk> - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, write to the Free - Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA - 02111-1307 USA. */ - -/* size_t strlen(const char *S) - * entry: r0 -> string - * exit: r0 = len - */ - - .text - .global strlen; - .type strlen,%function - .align 4; - -strlen: - bic r1, r0, $3 @ addr of word containing first byte - ldr r2, [r1], $4 @ get the first word - ands r3, r0, $3 @ how many bytes are duff? - rsb r0, r3, $0 @ get - that number into counter. - beq Laligned @ skip into main check routine if no - @ more - orr r2, r2, $0x000000ff @ set this byte to non-zero - subs r3, r3, $1 @ any more to do? - orrgt r2, r2, $0x0000ff00 @ if so, set this byte - subs r3, r3, $1 @ more? - orrgt r2, r2, $0x00ff0000 @ then set. -Laligned: @ here, we have a word in r2. Does it - tst r2, $0x000000ff @ contain any zeroes? - tstne r2, $0x0000ff00 @ - tstne r2, $0x00ff0000 @ - tstne r2, $0xff000000 @ - addne r0, r0, $4 @ if not, the string is 4 bytes longer - ldrne r2, [r1], $4 @ and we continue to the next word - bne Laligned @ -Llastword: @ drop through to here once we find a - tst r2, $0x000000ff @ - addne r0, r0, $1 @ - tstne r2, $0x0000ff00 @ and add up to 3 bytes on to it - addne r0, r0, $1 @ - tstne r2, $0x00ff0000 @ (if first three all non-zero, 4th - addne r0, r0, $1 @ must be zero) - //mov pc,lr - bx lr - -.size strlen,.-strlen; - |