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-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)