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+/* Copyright (C) 2002, 2003 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 *memcpy(void *s1, const void *s2, size_t n); */
+
+#if __BYTE_ORDER == __BIG_ENDIAN
+# define LWHI lwl /* high part is left in big-endian */
+# define SWHI swl /* high part is left in big-endian */
+# define LWLO lwr /* low part is right in big-endian */
+# define SWLO swr /* low part is right in big-endian */
+#else
+# define LWHI lwr /* high part is right in little-endian */
+# define SWHI swr /* high part is right in little-endian */
+# define LWLO lwl /* low part is left in little-endian */
+# define SWLO swl /* low part is left in little-endian */
+#endif
+
+ENTRY (memcpy)
+ .set noreorder
+
+ slti t0, a2, 8 # Less than 8?
+ bne t0, zero, L(last8)
+ move v0, a0 # Setup exit value before too late
+
+ xor t0, a1, a0 # Find a0/a1 displacement
+ andi t0, 0x3
+ bne t0, zero, L(shift) # Go handle the unaligned case
+ subu t1, zero, a1
+ andi t1, 0x3 # a0/a1 are aligned, but are we
+ beq t1, zero, L(chk8w) # starting in the middle of a word?
+ subu a2, t1
+ LWHI t0, 0(a1) # Yes we are... take care of that
+ addu a1, t1
+ SWHI t0, 0(a0)
+ addu a0, t1
+
+L(chk8w):
+ andi t0, a2, 0x1f # 32 or more bytes left?
+ beq t0, a2, L(chk1w)
+ subu a3, a2, t0 # Yes
+ addu a3, a1 # a3 = end address of loop
+ move a2, t0 # a2 = what will be left after loop
+L(lop8w):
+ lw t0, 0(a1) # Loop taking 8 words at a time
+ lw t1, 4(a1)
+ lw t2, 8(a1)
+ lw t3, 12(a1)
+ lw t4, 16(a1)
+ lw t5, 20(a1)
+ lw t6, 24(a1)
+ lw t7, 28(a1)
+ addiu a0, 32
+ addiu a1, 32
+ sw t0, -32(a0)
+ sw t1, -28(a0)
+ sw t2, -24(a0)
+ sw t3, -20(a0)
+ sw t4, -16(a0)
+ sw t5, -12(a0)
+ sw t6, -8(a0)
+ bne a1, a3, L(lop8w)
+ sw t7, -4(a0)
+
+L(chk1w):
+ andi t0, a2, 0x3 # 4 or more bytes left?
+ beq t0, a2, L(last8)
+ subu a3, a2, t0 # Yes, handle them one word at a time
+ addu a3, a1 # a3 again end address
+ move a2, t0
+L(lop1w):
+ lw t0, 0(a1)
+ addiu a0, 4
+ addiu a1, 4
+ bne a1, a3, L(lop1w)
+ sw t0, -4(a0)
+
+L(last8):
+ blez a2, L(lst8e) # Handle last 8 bytes, one at a time
+ addu a3, a2, a1
+L(lst8l):
+ lb t0, 0(a1)
+ addiu a0, 1
+ addiu a1, 1
+ bne a1, a3, L(lst8l)
+ sb t0, -1(a0)
+L(lst8e):
+ jr ra # Bye, bye
+ nop
+
+L(shift):
+ subu a3, zero, a0 # Src and Dest unaligned
+ andi a3, 0x3 # (unoptimized case...)
+ beq a3, zero, L(shft1)
+ subu a2, a3 # a2 = bytes left
+ LWHI t0, 0(a1) # Take care of first odd part
+ LWLO t0, 3(a1)
+ addu a1, a3
+ SWHI t0, 0(a0)
+ addu a0, a3
+L(shft1):
+ andi t0, a2, 0x3
+ subu a3, a2, t0
+ addu a3, a1
+L(shfth):
+ LWHI t1, 0(a1) # Limp through, word by word
+ LWLO t1, 3(a1)
+ addiu a0, 4
+ addiu a1, 4
+ bne a1, a3, L(shfth)
+ sw t1, -4(a0)
+ b L(last8) # Handle anything which may be left
+ move a2, t0
+
+ .set reorder
+END (memcpy)
+libc_hidden_builtin_def (memcpy)