summaryrefslogtreecommitdiff
path: root/libc/string/arm/memset.S
diff options
context:
space:
mode:
Diffstat (limited to 'libc/string/arm/memset.S')
-rw-r--r--libc/string/arm/memset.S72
1 files changed, 72 insertions, 0 deletions
diff --git a/libc/string/arm/memset.S b/libc/string/arm/memset.S
new file mode 100644
index 000000000..07d3913f9
--- /dev/null
+++ b/libc/string/arm/memset.S
@@ -0,0 +1,72 @@
+/* Copyright (C) 1998 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Philip Blundell <philb@gnu.org>
+
+ 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. */
+
+#include <sys/syscall.h>
+
+ .text
+ .global memset;
+ .type memset,%function
+ .align 4; \
+
+memset:
+ mov a4, a1
+ cmp a3, $8 @ at least 8 bytes to do?
+ blt 2f
+ orr a2, a2, a2, lsl $8
+ orr a2, a2, a2, lsl $16
+1:
+ tst a4, $3 @ aligned yet?
+ strneb a2, [a4], $1
+ subne a3, a3, $1
+ bne 1b
+ mov ip, a2
+1:
+ cmp a3, $8 @ 8 bytes still to do?
+ blt 2f
+ stmia a4!, {a2, ip}
+ sub a3, a3, $8
+ cmp a3, $8 @ 8 bytes still to do?
+ blt 2f
+ stmia a4!, {a2, ip}
+ sub a3, a3, $8
+ cmp a3, $8 @ 8 bytes still to do?
+ blt 2f
+ stmia a4!, {a2, ip}
+ sub a3, a3, $8
+ cmp a3, $8 @ 8 bytes still to do?
+ stmgeia a4!, {a2, ip}
+ subge a3, a3, $8
+ bge 1b
+2:
+ movs a3, a3 @ anything left?
+ moveq pc, lr @ nope
+ rsb a3, a3, $7
+ add pc, pc, a3, lsl $2
+ mov r0, r0
+ strb a2, [a4], $1
+ strb a2, [a4], $1
+ strb a2, [a4], $1
+ strb a2, [a4], $1
+ strb a2, [a4], $1
+ strb a2, [a4], $1
+ strb a2, [a4], $1
+ mov pc, lr
+
+.size memset,.-memset;
+