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+/* Copyright (C) 2002 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Hartvig Ekner <hartvige@mips.com>, 2002.
+
+ 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 <sysdep.h>
+#include <endian.h>
+
+
+/* void *memset(void *s, int c, size_t n).
+
+ This routine could be optimized further for MIPS64, but this is left
+ as an exercise for the future. When it is done, the file should be kept
+ as a sisterfile to this one, and placed in the sysdeps/mips/mips64
+ directory. */
+
+#if __BYTE_ORDER == __BIG_ENDIAN
+# define SWHI swl /* high part is left in big-endian */
+#else
+# define SWHI swr /* high part is right in little-endian */
+#endif
+
+ENTRY (memset)
+ .set noreorder
+
+ slti t1, a2, 8 # Less than 8?
+ bne t1, zero, $last8
+ move v0, a0 # Setup exit value before too late
+
+ beq a1, zero, $ueven # If zero pattern, no need to extend
+ andi a1, 0xff # Avoid problems with bogus arguments
+ sll t0, a1, 8
+ or a1, t0
+ sll t0, a1, 16
+ or a1, t0 # a1 is now pattern in full word
+
+$ueven: subu t0, zero, a0 # Unaligned address?
+ andi t0, 0x3
+ beq t0, zero, $chkw
+ subu a2, t0
+ SWHI a1, 0(a0) # Yes, handle first unaligned part
+ addu a0, t0 # Now both a0 and a2 are updated
+
+$chkw: andi t0, a2, 0x7 # Enough left for one loop iteration?
+ beq t0, a2, $chkl
+ subu a3, a2, t0
+ addu a3, a0 # a3 is last loop address +1
+ move a2, t0 # a2 is now # of bytes left after loop
+$loopw: addiu a0, 8 # Handle 2 words pr. iteration
+ sw a1, -8(a0)
+ bne a0, a3, $loopw
+ sw a1, -4(a0)
+
+$chkl: andi t0, a2, 0x4 # Check if there is at least a full
+ beq t0, zero, $last8 # word remaining after the loop
+ subu a2, t0
+ sw a1, 0(a0) # Yes...
+ addiu a0, 4
+
+$last8: blez a2, $exit # Handle last 8 bytes (if cnt>0)
+ addu a3, a2, a0 # a3 is last address +1
+$lst8l: addiu a0, 1
+ bne a0, a3, $lst8l
+ sb a1, -1(a0)
+$exit: j ra # Bye, bye
+ nop
+
+ .set reorder
+END (memset)