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-rw-r--r--ports/sysdeps/mips/mips64/memcpy.S138
1 files changed, 138 insertions, 0 deletions
diff --git a/ports/sysdeps/mips/mips64/memcpy.S b/ports/sysdeps/mips/mips64/memcpy.S
new file mode 100644
index 0000000000..49ef34d0c6
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+++ b/ports/sysdeps/mips/mips64/memcpy.S
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+/* Copyright (C) 2002-2012 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Hartvig Ekner <hartvige@mips.com>, 2002.
+ Ported to mips3 n32/n64 by Alexandre Oliva <aoliva@redhat.com>
+
+ 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>
+#include <sys/asm.h>
+
+
+/* void *memcpy(void *s1, const void *s2, size_t n);
+
+ This could probably be optimized further. */
+
+#if __MIPSEB
+# define LDHI ldl /* high part is left in big-endian */
+# define SDHI sdl /* high part is left in big-endian */
+# define LDLO ldr /* low part is right in big-endian */
+# define SDLO sdr /* low part is right in big-endian */
+#else
+# define LDHI ldr /* high part is right in little-endian */
+# define SDHI sdr /* high part is right in little-endian */
+# define LDLO ldl /* low part is left in little-endian */
+# define SDLO sdl /* low part is left in little-endian */
+#endif
+
+ENTRY (memcpy)
+ .set noreorder
+
+ slti t0, a2, 16 # Less than 16?
+ bne t0, zero, L(last16)
+ move v0, a0 # Setup exit value before too late
+
+ xor t0, a1, a0 # Find a0/a1 displacement
+ andi t0, 0x7
+ bne t0, zero, L(shift) # Go handle the unaligned case
+ PTR_SUBU t1, zero, a1
+ andi t1, 0x7 # a0/a1 are aligned, but are we
+ beq t1, zero, L(chk8w) # starting in the middle of a word?
+ PTR_SUBU a2, t1
+ LDHI t0, 0(a1) # Yes we are... take care of that
+ PTR_ADDU a1, t1
+ SDHI t0, 0(a0)
+ PTR_ADDU a0, t1
+
+L(chk8w):
+ andi t0, a2, 0x3f # 64 or more bytes left?
+ beq t0, a2, L(chk1w)
+ PTR_SUBU a3, a2, t0 # Yes
+ PTR_ADDU a3, a1 # a3 = end address of loop
+ move a2, t0 # a2 = what will be left after loop
+L(lop8w):
+ ld t0, 0(a1) # Loop taking 8 words at a time
+ ld t1, 8(a1)
+ ld t2, 16(a1)
+ ld t3, 24(a1)
+ ld ta0, 32(a1)
+ ld ta1, 40(a1)
+ ld ta2, 48(a1)
+ ld ta3, 56(a1)
+ PTR_ADDIU a0, 64
+ PTR_ADDIU a1, 64
+ sd t0, -64(a0)
+ sd t1, -56(a0)
+ sd t2, -48(a0)
+ sd t3, -40(a0)
+ sd ta0, -32(a0)
+ sd ta1, -24(a0)
+ sd ta2, -16(a0)
+ bne a1, a3, L(lop8w)
+ sd ta3, -8(a0)
+
+L(chk1w):
+ andi t0, a2, 0x7 # 8 or more bytes left?
+ beq t0, a2, L(last16)
+ PTR_SUBU a3, a2, t0 # Yes, handle them one dword at a time
+ PTR_ADDU a3, a1 # a3 again end address
+ move a2, t0
+L(lop1w):
+ ld t0, 0(a1)
+ PTR_ADDIU a0, 8
+ PTR_ADDIU a1, 8
+ bne a1, a3, L(lop1w)
+ sd t0, -8(a0)
+
+L(last16):
+ blez a2, L(lst16e) # Handle last 16 bytes, one at a time
+ PTR_ADDU a3, a2, a1
+L(lst16l):
+ lb t0, 0(a1)
+ PTR_ADDIU a0, 1
+ PTR_ADDIU a1, 1
+ bne a1, a3, L(lst16l)
+ sb t0, -1(a0)
+L(lst16e):
+ jr ra # Bye, bye
+ nop
+
+L(shift):
+ PTR_SUBU a3, zero, a0 # Src and Dest unaligned
+ andi a3, 0x7 # (unoptimized case...)
+ beq a3, zero, L(shft1)
+ PTR_SUBU a2, a3 # a2 = bytes left
+ LDHI t0, 0(a1) # Take care of first odd part
+ LDLO t0, 7(a1)
+ PTR_ADDU a1, a3
+ SDHI t0, 0(a0)
+ PTR_ADDU a0, a3
+L(shft1):
+ andi t0, a2, 0x7
+ PTR_SUBU a3, a2, t0
+ PTR_ADDU a3, a1
+L(shfth):
+ LDHI t1, 0(a1) # Limp through, dword by dword
+ LDLO t1, 7(a1)
+ PTR_ADDIU a0, 8
+ PTR_ADDIU a1, 8
+ bne a1, a3, L(shfth)
+ sd t1, -8(a0)
+ b L(last16) # Handle anything which may be left
+ move a2, t0
+
+ .set reorder
+END (memcpy)
+libc_hidden_builtin_def (memcpy)