summaryrefslogtreecommitdiff
path: root/ports/sysdeps/arm/memset.S
diff options
context:
space:
mode:
Diffstat (limited to 'ports/sysdeps/arm/memset.S')
-rw-r--r--ports/sysdeps/arm/memset.S64
1 files changed, 64 insertions, 0 deletions
diff --git a/ports/sysdeps/arm/memset.S b/ports/sysdeps/arm/memset.S
new file mode 100644
index 0000000000..a29031c266
--- /dev/null
+++ b/ports/sysdeps/arm/memset.S
@@ -0,0 +1,64 @@
+/* Copyright (C) 1998, 2003 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, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+
+/* void *memset (dstpp, c, len) */
+
+ENTRY(memset)
+ mov r3, r0
+ cmp r2, #8
+ bcc 2f @ less than 8 bytes to move
+
+1:
+ tst r3, #3 @ aligned yet?
+ strneb r1, [r3], #1
+ subne r2, r2, #1
+ bne 1b
+
+ and r1, r1, #255 @ clear any sign bits
+ orr r1, r1, r1, lsl $8
+ orr r1, r1, r1, lsl $16
+ mov ip, r1
+
+1:
+ subs r2, r2, #8
+ stmcsia r3!, {r1, ip} @ store up to 32 bytes per loop iteration
+ subcss r2, r2, #8
+ stmcsia r3!, {r1, ip}
+ subcss r2, r2, #8
+ stmcsia r3!, {r1, ip}
+ subcss r2, r2, #8
+ stmcsia r3!, {r1, ip}
+ bcs 1b
+
+ and r2, r2, #7
+2:
+ subs r2, r2, #1 @ store up to 4 bytes per loop iteration
+ strcsb r1, [r3], #1
+ subcss r2, r2, #1
+ strcsb r1, [r3], #1
+ subcss r2, r2, #1
+ strcsb r1, [r3], #1
+ subcss r2, r2, #1
+ strcsb r1, [r3], #1
+ bcs 2b
+
+ DO_RET(lr)
+END(memset)
+libc_hidden_builtin_def (memset)