2012-10-31 Steve Ellcey <sellcey@mips.com>

	* sysdeps/mips/memcpy.S: Add prefetching and more unrolling, make
	it work in 32 or 64 bit modes.
	* sysdeps/mips/mips64/memcpy.S: Remove.

2 files changed, 603 insertions, 243 deletions

diff --git a/ports/sysdeps/mips/memcpy.S b/ports/sysdeps/mips/memcpy.S
index 753f67ca17..198b2c509d 100644
--- a/ports/sysdeps/mips/memcpy.S
+++ b/ports/sysdeps/mips/memcpy.S
@@ -1,7 +1,8 @@
-/* Copyright (C) 2002-2012 Free Software Foundation, Inc.
+/* Copyright (C) 2012 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
-   Contributed by Hartvig Ekner <hartvige@mips.com>, 2002.
-
+  
+   Contributed by MIPS Technologies, Inc.
+  
    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
@@ -16,119 +17,616 @@
    License along with the GNU C Library.  If not, see
    <http://www.gnu.org/licenses/>.  */
 
+#ifdef ANDROID_CHANGES
+#include "machine/asm.h"
+#include "machine/regdef.h"
+#define USE_MEMMOVE_FOR_OVERLAP
+#define PREFETCH_LOAD_HINT PREFETCH_HINT_LOAD_STREAMED
+#define PREFETCH_STORE_HINT PREFETCH_HINT_PREPAREFORSTORE
+#elif _LIBC
 #include <sysdep.h>
+#include <regdef.h>
+#include <sys/asm.h>
+#define PREFETCH_LOAD_HINT PREFETCH_HINT_LOAD_STREAMED
+#define PREFETCH_STORE_HINT PREFETCH_HINT_STORE_STREAMED
+#elif _COMPILING_NEWLIB
+#include "machine/asm.h"
+#include "machine/regdef.h"
+#define PREFETCH_LOAD_HINT PREFETCH_HINT_LOAD_STREAMED
+#define PREFETCH_STORE_HINT PREFETCH_HINT_STORE_STREAMED
+#else
+#include <regdef.h>
+#include <sys/asm.h>
+#endif
+
+#if (_MIPS_ISA == _MIPS_ISA_MIPS4) || (_MIPS_ISA == _MIPS_ISA_MIPS5) || \
+    (_MIPS_ISA == _MIPS_ISA_MIPS32) || (_MIPS_ISA == _MIPS_ISA_MIPS64)
+#ifndef DISABLE_PREFETCH
+#define USE_PREFETCH
+#endif
+#endif
+
+#if (_MIPS_SIM == _ABI64) || (_MIPS_SIM == _ABIN32)
+#ifndef DISABLE_DOUBLE
+#define USE_DOUBLE
+#endif
+#endif
+
+
+
+/* Some asm.h files do not have the L macro definition.  */
+#ifndef L
+#if _MIPS_SIM == _ABIO32
+# define L(label) $L ## label
+#else
+# define L(label) .L ## label
+#endif
+#endif
+
+/* Some asm.h files do not have the PTR_ADDIU macro definition.  */
+#ifndef PTR_ADDIU
+#ifdef USE_DOUBLE
+#define PTR_ADDIU	daddiu
+#else
+#define PTR_ADDIU	addiu
+#endif
+#endif
+
+/* Some asm.h files do not have the PTR_SRA macro definition.  */
+#ifndef PTR_SRA
+#ifdef USE_DOUBLE
+#define PTR_SRA		dsra
+#else
+#define PTR_SRA		sra
+#endif
+#endif
+
 
+/*
+ * Using PREFETCH_HINT_LOAD_STREAMED instead of PREFETCH_LOAD on load
+ * prefetches appears to offer a slight preformance advantage.
+ *
+ * Using PREFETCH_HINT_PREPAREFORSTORE instead of PREFETCH_STORE
+ * or PREFETCH_STORE_STREAMED offers a large performance advantage
+ * but PREPAREFORSTORE has some special restrictions to consider.
+ *
+ * Prefetch with the 'prepare for store' hint does not copy a memory
+ * location into the cache, it just allocates a cache line and zeros
+ * it out.  This means that if you do not write to the entire cache
+ * line before writing it out to memory some data will get zero'ed out
+ * when the cache line is written back to memory and data will be lost.
+ *
+ * Also if you are using this memcpy to copy overlapping buffers it may
+ * not behave correctly when using the 'prepare for store' hint.  If you
+ * use the 'prepare for store' prefetch on a memory area that is in the
+ * memcpy source (as well as the memcpy destination), then you will get
+ * some data zero'ed out before you have a chance to read it and data will
+ * be lost.
+ *
+ * If you are going to use this memcpy routine with the 'prepare for store'
+ * prefetch you may want to set USE_MEMMOVE_FOR_OVERLAP in order to avoid
+ * the problem of running memcpy on overlapping buffers.
+ *
+ * There are ifdef'ed sections of this memcpy to make sure that it does not
+ * do prefetches on cache lines that are not going to be completely written.
+ * This code is only needed and only used when PREFETCH_STORE_HINT is set to 
+ * PREFETCH_HINT_PREPAREFORSTORE.  This code assumes that cache lines are
+ * 32 bytes and if the cache line is larger it will not work correctly.
+ */
 
-/* void *memcpy(void *s1, const void *s2, size_t n);  */
+#ifdef USE_PREFETCH
+# define PREFETCH_HINT_LOAD		0
+# define PREFETCH_HINT_STORE		1
+# define PREFETCH_HINT_LOAD_STREAMED	4
+# define PREFETCH_HINT_STORE_STREAMED	5
+# define PREFETCH_HINT_LOAD_RETAINED	6
+# define PREFETCH_HINT_STORE_RETAINED	7
+# define PREFETCH_HINT_WRITEBACK_INVAL	25
+# define PREFETCH_HINT_PREPAREFORSTORE	30
+
+/*
+ * If we have not picked out what hints to use at this point use the
+ * standard load and store prefetch hints.
+ */
+#ifndef PREFETCH_STORE_HINT
+# define PREFETCH_STORE_HINT PREFETCH_HINT_STORE
+#endif
+#ifndef PREFETCH_LOAD_HINT
+# define PREFETCH_LOAD_HINT PREFETCH_HINT_LOAD
+#endif
 
+/*
+ * We double everything when USE_DOUBLE is true so we do 2 prefetches to
+ * get 64 bytes in that case.  The assumption is that each individual 
+ * prefetch brings in 32 bytes.
+ */
+#ifdef USE_DOUBLE
+# define PREFETCH_CHUNK 64
+# define PREFETCH_FOR_LOAD(chunk, reg) \
+ pref PREFETCH_LOAD_HINT, (chunk)*32(reg); \
+ pref PREFETCH_LOAD_HINT, ((chunk)+1)*32(reg)
+# define PREFETCH_FOR_STORE(chunk, reg) \
+ pref PREFETCH_STORE_HINT, (chunk)*32(reg); \
+ pref PREFETCH_STORE_HINT, ((chunk)+1)*32(reg)
+#else
+# define PREFETCH_CHUNK 32
+# define PREFETCH_FOR_LOAD(chunk, reg) \
+ pref PREFETCH_LOAD_HINT, (chunk)*32(reg)
+# define PREFETCH_FOR_STORE(chunk, reg) \
+ pref PREFETCH_STORE_HINT, (chunk)*32(reg)
+#endif
+# define PREFETCH_LIMIT (5 * PREFETCH_CHUNK)
+#else /* USE_PREFETCH not defined */
+# define PREFETCH_FOR_LOAD(offset, reg)
+# define PREFETCH_FOR_STORE(offset, reg)
+#endif
+
+/* Allow the routine to be named something else if desired.  */
+#ifndef MEMCPY_NAME
+#define MEMCPY_NAME memcpy
+#endif
+
+/* We use these 32/64 bit registers as temporaries to do the copying.  */
+#define REG0 t0
+#define REG1 t1
+#define REG2 t2
+#define REG3 t3
+#if _MIPS_SIM == _ABIO32
+#  define REG4 t4
+#  define REG5 t5
+#  define REG6 t6
+#  define REG7 t7
+#else
+#  define REG4 ta0
+#  define REG5 ta1
+#  define REG6 ta2
+#  define REG7 ta3
+#endif
+
+/* We load/store 64 bits at a time when USE_DOUBLE is true.
+ * The C_ prefix stands for CHUNK and is used to avoid macro name
+ * conflicts with system header files.  */
+
+#ifdef USE_DOUBLE
+#  define C_ST	sd
+#  define C_LD	ld
 #if __MIPSEB
-#  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	*/
+#  define C_LDHI	ldl	/* high part is left in big-endian	*/
+#  define C_STHI	sdl	/* high part is left in big-endian	*/
+#  define C_LDLO	ldr	/* low part is right in big-endian	*/
+#  define C_STLO	sdr	/* low part is right in big-endian	*/
+#else
+#  define C_LDHI	ldr	/* high part is right in little-endian	*/
+#  define C_STHI	sdr	/* high part is right in little-endian	*/
+#  define C_LDLO	ldl	/* low part is left in little-endian	*/
+#  define C_STLO	sdl	/* low part is left in little-endian	*/
+#endif
+#else
+#  define C_ST	sw
+#  define C_LD	lw
+#if __MIPSEB
+#  define C_LDHI	lwl	/* high part is left in big-endian	*/
+#  define C_STHI	swl	/* high part is left in big-endian	*/
+#  define C_LDLO	lwr	/* low part is right in big-endian	*/
+#  define C_STLO	swr	/* low part is right in big-endian	*/
+#else
+#  define C_LDHI	lwr	/* high part is right in little-endian	*/
+#  define C_STHI	swr	/* high part is right in little-endian	*/
+#  define C_LDLO	lwl	/* low part is left in little-endian	*/
+#  define C_STLO	swl	/* low part is left in little-endian	*/
+#endif
+#endif
+
+/* Bookkeeping values for 32 vs. 64 bit mode.  */
+#ifdef USE_DOUBLE
+#  define NSIZE 8
+#  define NSIZEMASK 0x3f
+#  define NSIZEDMASK 0x7f
 #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	*/
+#  define NSIZE 4
+#  define NSIZEMASK 0x1f
+#  define NSIZEDMASK 0x3f
 #endif
+#define UNIT(unit) ((unit)*NSIZE)
+#define UNITM1(unit) (((unit)*NSIZE)-1)
 
-ENTRY (memcpy)
+#ifdef ANDROID_CHANGES
+LEAF(MEMCPY_NAME, 0)
+#else
+LEAF(MEMCPY_NAME)
+#endif
+	.set	nomips16
 	.set	noreorder
+/*
+ * Below we handle the case where memcpy is called with overlapping src and dst.
+ * Although memcpy is not required to handle this case, some parts of Android
+ * like Skia rely on such usage. We call memmove to handle such cases.
+ */
+#ifdef USE_MEMMOVE_FOR_OVERLAP
+	PTR_SUBU t0,a0,a1
+	PTR_SRA	t2,t0,31
+	xor	t1,t0,t2
+	PTR_SUBU t0,t1,t2
+	sltu	t2,t0,a2
+	beq	t2,zero,L(memcpy)
+	la	t9,memmove
+	jr	t9
+	 nop
+L(memcpy):
+#endif
+/*
+ * If the size is less then 2*NSIZE (8 or 16), go to L(lastb).  Regardless of
+ * size, copy dst pointer to v0 for the return value.
+ */
+	slti	t2,a2,(2 * NSIZE)
+	bne	t2,zero,L(lastb)
+	move	v0,a0
+/*
+ * If src and dst have different alignments, go to L(unaligned), if they
+ * have the same alignment (but are not actually aligned) do a partial
+ * load/store to make them aligned.  If they are both already aligned
+ * we can start copying at L(aligned).
+ */
+	xor	t8,a1,a0
+	andi	t8,t8,(NSIZE-1)		/* t8 is a0/a1 word-displacement */
+	bne	t8,zero,L(unaligned)
+	PTR_SUBU a3, zero, a0
+
+	andi	a3,a3,(NSIZE-1)		/* copy a3 bytes to align a0/a1	  */
+	beq	a3,zero,L(aligned)	/* if a3=0, it is already aligned */
+	PTR_SUBU a2,a2,a3		/* a2 is the remining bytes count */
+
+	C_LDHI	t8,0(a1)
+	PTR_ADDU a1,a1,a3
+	C_STHI	t8,0(a0)
+	PTR_ADDU a0,a0,a3
+
+/*
+ * Now dst/src are both aligned to (word or double word) aligned addresses
+ * Set a2 to count how many bytes we have to copy after all the 64/128 byte
+ * chunks are copied and a3 to the dst pointer after all the 64/128 byte 
+ * chunks have been copied.  We will loop, incrementing a0 and a1 until a0
+ * equals a3.
+ */
+
+L(aligned):
+	andi	t8,a2,NSIZEDMASK /* any whole 64-byte/128-byte chunks? */
+	beq	a2,t8,L(chkw)	 /* if a2==t8, no 64-byte/128-byte chunks */
+	PTR_SUBU a3,a2,t8	 /* subtract from a2 the reminder */
+	PTR_ADDU a3,a0,a3	 /* Now a3 is the final dst after loop */
+
+/* When in the loop we may prefetch with the 'prepare to store' hint,
+ * in this case the a0+x should not be past the "t0-32" address.  This
+ * means: for x=128 the last "safe" a0 address is "t0-160".  Alternatively,
+ * for x=64 the last "safe" a0 address is "t0-96" In the current version we
+ * will use "prefetch hint,128(a0)", so "t0-160" is the limit.
+ */
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
+	PTR_ADDU t0,a0,a2		/* t0 is the "past the end" address */
+	PTR_SUBU t9,t0,PREFETCH_LIMIT	/* t9 is the "last safe pref" address */
+#endif
+	PREFETCH_FOR_LOAD  (0, a1)
+	PREFETCH_FOR_LOAD  (1, a1)
+	PREFETCH_FOR_LOAD  (2, a1)
+	PREFETCH_FOR_STORE (1, a0)
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
+	sltu	v1,t9,a0		/* If a0 > t9 don't use next prefetch */
+	bgtz	v1,L(loop16w)
+	nop
+#endif
+	PREFETCH_FOR_STORE (2, a0)
+L(loop16w):
+	PREFETCH_FOR_LOAD  (3, a1)
+	C_LD	t0,UNIT(0)(a1)
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
+	bgtz	v1,L(skip_pref30_96)
+#endif
+	C_LD	t1,UNIT(1)(a1)
+	PREFETCH_FOR_STORE (3, a0)
+L(skip_pref30_96):
+	C_LD	REG2,UNIT(2)(a1)
+	C_LD	REG3,UNIT(3)(a1)
+	C_LD	REG4,UNIT(4)(a1)
+	C_LD	REG5,UNIT(5)(a1)
+	C_LD	REG6,UNIT(6)(a1)
+	C_LD	REG7,UNIT(7)(a1)
+        PREFETCH_FOR_LOAD (4, a1)
+
+	C_ST	t0,UNIT(0)(a0)
+	C_ST	t1,UNIT(1)(a0)
+	C_ST	REG2,UNIT(2)(a0)
+	C_ST	REG3,UNIT(3)(a0)
+	C_ST	REG4,UNIT(4)(a0)
+	C_ST	REG5,UNIT(5)(a0)
+	C_ST	REG6,UNIT(6)(a0)
+	C_ST	REG7,UNIT(7)(a0)
+
+	C_LD	t0,UNIT(8)(a1)
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
+	bgtz	v1,L(skip_pref30_128)
+#endif
+	C_LD	t1,UNIT(9)(a1)
+	PREFETCH_FOR_STORE (4, a0)
+L(skip_pref30_128):
+	C_LD	REG2,UNIT(10)(a1)
+	C_LD	REG3,UNIT(11)(a1)
+	C_LD	REG4,UNIT(12)(a1)
+	C_LD	REG5,UNIT(13)(a1)
+	C_LD	REG6,UNIT(14)(a1)
+	C_LD	REG7,UNIT(15)(a1)
+        PREFETCH_FOR_LOAD (5, a1)
+	C_ST	t0,UNIT(8)(a0)
+	C_ST	t1,UNIT(9)(a0)
+	C_ST	REG2,UNIT(10)(a0)
+	C_ST	REG3,UNIT(11)(a0)
+	C_ST	REG4,UNIT(12)(a0)
+	C_ST	REG5,UNIT(13)(a0)
+	C_ST	REG6,UNIT(14)(a0)
+	C_ST	REG7,UNIT(15)(a0)
+	PTR_ADDIU a0,a0,UNIT(16)	/* adding 64/128 to dest */
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
+	sltu	v1,t9,a0
+#endif
+	bne	a0,a3,L(loop16w)
+	PTR_ADDIU a1,a1,UNIT(16)	/* adding 64/128 to src */
+	move	a2,t8
+
+/* Here we have src and dest word-aligned but less than 64-bytes or
+ * 128 bytes to go.  Check for a 32(64) byte chunk and copy if if there
+ * is one.  Otherwise jump down to L(chk1w) to handle the tail end of
+ * the copy.
+ */
+
+L(chkw):
+	PREFETCH_FOR_LOAD (0, a1)
+	andi	t8,a2,NSIZEMASK	/* Is there a 32-byte/64-byte chunk.  */
+				/* The t8 is the reminder count past 32-bytes */
+	beq	a2,t8,L(chk1w)	/* When a2=t8, no 32-byte chunk  */
+	nop
+	C_LD	t0,UNIT(0)(a1)
+	C_LD	t1,UNIT(1)(a1)
+	C_LD	REG2,UNIT(2)(a1)
+	C_LD	REG3,UNIT(3)(a1)
+	C_LD	REG4,UNIT(4)(a1)
+	C_LD	REG5,UNIT(5)(a1)
+	C_LD	REG6,UNIT(6)(a1)
+	C_LD	REG7,UNIT(7)(a1)
+	PTR_ADDIU a1,a1,UNIT(8)
+	C_ST	t0,UNIT(0)(a0)
+	C_ST	t1,UNIT(1)(a0)
+	C_ST	REG2,UNIT(2)(a0)
+	C_ST	REG3,UNIT(3)(a0)
+	C_ST	REG4,UNIT(4)(a0)
+	C_ST	REG5,UNIT(5)(a0)
+	C_ST	REG6,UNIT(6)(a0)
+	C_ST	REG7,UNIT(7)(a0)
+	PTR_ADDIU a0,a0,UNIT(8)
+
+/*
+ * Here we have less then 32(64) bytes to copy.  Set up for a loop to
+ * copy one word (or double word) at a time.  Set a2 to count how many
+ * bytes we have to copy after all the word (or double word) chunks are
+ * copied and a3 to the dst pointer after all the (d)word chunks have
+ * been copied.  We will loop, incrementing a0 and a1 until a0 equals a3.
+ */
+L(chk1w):
+	andi	a2,t8,(NSIZE-1)	/* a2 is the reminder past one (d)word chunks */
+	beq	a2,t8,L(lastb)
+	PTR_SUBU a3,t8,a2	/* a3 is count of bytes in one (d)word chunks */
+	PTR_ADDU a3,a0,a3	/* a3 is the dst address after loop */
+
+/* copying in words (4-byte or 8-byte chunks) */
+L(wordCopy_loop):
+	C_LD	REG3,UNIT(0)(a1)
+	PTR_ADDIU a1,a1,UNIT(1)
+	PTR_ADDIU a0,a0,UNIT(1)
+	bne	a0,a3,L(wordCopy_loop)
+	C_ST	REG3,UNIT(-1)(a0)
 
-	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
+/* Copy the last 8 (or 16) bytes */
+L(lastb):
+	blez	a2,L(leave)
+	PTR_ADDU a3,a0,a2	/* a3 is the last dst address */
+L(lastbloop):
+	lb	v1,0(a1)
+	PTR_ADDIU a1,a1,1
+	PTR_ADDIU a0,a0,1
+	bne	a0,a3,L(lastbloop)
+	sb	v1,-1(a0)
+L(leave):
+	j	ra
 	nop
+/*
+ * UNALIGNED case, got here with a3 = "negu a0"
+ * This code is nearly identical to the aligned code above
+ * but only the destination (not the source) gets aligned
+ * so we need to do partial loads of the source followed
+ * by normal stores to the destination (once we have aligned
+ * the destination).
+ */
+
+L(unaligned):
+	andi	a3,a3,(NSIZE-1)	/* copy a3 bytes to align a0/a1 */
+	beqz	a3,L(ua_chk16w) /* if a3=0, it is already aligned */
+	PTR_SUBU a2,a2,a3	/* a2 is the remining bytes count */
+
+	C_LDHI	v1,UNIT(0)(a1)
+	C_LDLO	v1,UNITM1(1)(a1)
+	PTR_ADDU a1,a1,a3
+	C_STHI	v1,UNIT(0)(a0)
+	PTR_ADDU a0,a0,a3
+
+/*
+ *  Now the destination (but not the source) is aligned
+ * Set a2 to count how many bytes we have to copy after all the 64/128 byte
+ * chunks are copied and a3 to the dst pointer after all the 64/128 byte
+ * chunks have been copied.  We will loop, incrementing a0 and a1 until a0
+ * equals a3.
+ */
 
-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
+L(ua_chk16w):
+	andi	t8,a2,NSIZEDMASK /* any whole 64-byte/128-byte chunks? */
+	beq	a2,t8,L(ua_chkw) /* if a2==t8, no 64-byte/128-byte chunks */
+	PTR_SUBU a3,a2,t8	 /* subtract from a2 the reminder */
+	PTR_ADDU a3,a0,a3	 /* Now a3 is the final dst after loop */
 
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
+	PTR_ADDU t0,a0,a2	  /* t0 is the "past the end" address */
+	PTR_SUBU t9,t0,PREFETCH_LIMIT /* t9 is the "last safe pref" address */
+#endif
+	PREFETCH_FOR_LOAD  (0, a1)
+	PREFETCH_FOR_LOAD  (1, a1)
+	PREFETCH_FOR_LOAD  (2, a1)
+	PREFETCH_FOR_STORE (1, a0)
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
+	sltu	v1,t9,a0
+	bgtz	v1,L(ua_loop16w)  /* skip prefetch for too short arrays */
+	nop
+#endif
+	PREFETCH_FOR_STORE (2, a0)
+L(ua_loop16w):
+	PREFETCH_FOR_LOAD  (3, a1)
+	C_LDHI	t0,UNIT(0)(a1)
+	C_LDLO	t0,UNITM1(1)(a1)
+	C_LDHI	t1,UNIT(1)(a1)
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
+	bgtz	v1,L(ua_skip_pref30_96)
+#endif
+	C_LDLO	t1,UNITM1(2)(a1)
+	PREFETCH_FOR_STORE (3, a0)
+L(ua_skip_pref30_96):
+	C_LDHI	REG2,UNIT(2)(a1)
+	C_LDLO	REG2,UNITM1(3)(a1)
+	C_LDHI	REG3,UNIT(3)(a1)
+	C_LDLO	REG3,UNITM1(4)(a1)
+	C_LDHI	REG4,UNIT(4)(a1)
+	C_LDLO	REG4,UNITM1(5)(a1)
+	C_LDHI	REG5,UNIT(5)(a1)
+	C_LDLO	REG5,UNITM1(6)(a1)
+	C_LDHI	REG6,UNIT(6)(a1)
+	C_LDLO	REG6,UNITM1(7)(a1)
+	C_LDHI	REG7,UNIT(7)(a1)
+	C_LDLO	REG7,UNITM1(8)(a1)
+        PREFETCH_FOR_LOAD (4, a1)
+	C_ST	t0,UNIT(0)(a0)
+	C_ST	t1,UNIT(1)(a0)
+	C_ST	REG2,UNIT(2)(a0)
+	C_ST	REG3,UNIT(3)(a0)
+	C_ST	REG4,UNIT(4)(a0)
+	C_ST	REG5,UNIT(5)(a0)
+	C_ST	REG6,UNIT(6)(a0)
+	C_ST	REG7,UNIT(7)(a0)
+	C_LDHI	t0,UNIT(8)(a1)
+	C_LDLO	t0,UNITM1(9)(a1)
+	C_LDHI	t1,UNIT(9)(a1)
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
+	bgtz	v1,L(ua_skip_pref30_128)
+#endif
+	C_LDLO	t1,UNITM1(10)(a1)
+	PREFETCH_FOR_STORE (4, a0)
+L(ua_skip_pref30_128):
+	C_LDHI	REG2,UNIT(10)(a1)
+	C_LDLO	REG2,UNITM1(11)(a1)
+	C_LDHI	REG3,UNIT(11)(a1)
+	C_LDLO	REG3,UNITM1(12)(a1)
+	C_LDHI	REG4,UNIT(12)(a1)
+	C_LDLO	REG4,UNITM1(13)(a1)
+	C_LDHI	REG5,UNIT(13)(a1)
+	C_LDLO	REG5,UNITM1(14)(a1)
+	C_LDHI	REG6,UNIT(14)(a1)
+	C_LDLO	REG6,UNITM1(15)(a1)
+	C_LDHI	REG7,UNIT(15)(a1)
+	C_LDLO	REG7,UNITM1(16)(a1)
+        PREFETCH_FOR_LOAD (5, a1)
+	C_ST	t0,UNIT(8)(a0)
+	C_ST	t1,UNIT(9)(a0)
+	C_ST	REG2,UNIT(10)(a0)
+	C_ST	REG3,UNIT(11)(a0)
+	C_ST	REG4,UNIT(12)(a0)
+	C_ST	REG5,UNIT(13)(a0)
+	C_ST	REG6,UNIT(14)(a0)
+	C_ST	REG7,UNIT(15)(a0)
+	PTR_ADDIU a0,a0,UNIT(16)	/* adding 64/128 to dest */
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
+	sltu	v1,t9,a0
+#endif
+	bne	a0,a3,L(ua_loop16w)
+	PTR_ADDIU a1,a1,UNIT(16)	/* adding 64/128 to src */
+	move	a2,t8
+
+/* Here we have src and dest word-aligned but less than 64-bytes or
+ * 128 bytes to go.  Check for a 32(64) byte chunk and copy if if there
+ * is one.  Otherwise jump down to L(ua_chk1w) to handle the tail end of
+ * the copy.  */
+
+L(ua_chkw):
+	PREFETCH_FOR_LOAD (0, a1)
+	andi	t8,a2,NSIZEMASK	  /* Is there a 32-byte/64-byte chunk.  */
+				  /* t8 is the reminder count past 32-bytes */
+	beq	a2,t8,L(ua_chk1w) /* When a2=t8, no 32-byte chunk */
+	nop
+	C_LDHI	t0,UNIT(0)(a1)
+	C_LDLO	t0,UNITM1(1)(a1)
+	C_LDHI	t1,UNIT(1)(a1)
+	C_LDLO	t1,UNITM1(2)(a1)
+	C_LDHI	REG2,UNIT(2)(a1)
+	C_LDLO	REG2,UNITM1(3)(a1)
+	C_LDHI	REG3,UNIT(3)(a1)
+	C_LDLO	REG3,UNITM1(4)(a1)
+	C_LDHI	REG4,UNIT(4)(a1)
+	C_LDLO	REG4,UNITM1(5)(a1)
+	C_LDHI	REG5,UNIT(5)(a1)
+	C_LDLO	REG5,UNITM1(6)(a1)
+	C_LDHI	REG6,UNIT(6)(a1)
+	C_LDLO	REG6,UNITM1(7)(a1)
+	C_LDHI	REG7,UNIT(7)(a1)
+	C_LDLO	REG7,UNITM1(8)(a1)
+	PTR_ADDIU a1,a1,UNIT(8)
+	C_ST	t0,UNIT(0)(a0)
+	C_ST	t1,UNIT(1)(a0)
+	C_ST	REG2,UNIT(2)(a0)
+	C_ST	REG3,UNIT(3)(a0)
+	C_ST	REG4,UNIT(4)(a0)
+	C_ST	REG5,UNIT(5)(a0)
+	C_ST	REG6,UNIT(6)(a0)
+	C_ST	REG7,UNIT(7)(a0)
+	PTR_ADDIU a0,a0,UNIT(8)
+/*
+ * Here we have less then 32(64) bytes to copy.  Set up for a loop to
+ * copy one word (or double word) at a time.
+ */
+L(ua_chk1w):
+	andi	a2,t8,(NSIZE-1)	/* a2 is the reminder past one (d)word chunks */
+	beq	a2,t8,L(ua_smallCopy)
+	PTR_SUBU a3,t8,a2	/* a3 is count of bytes in one (d)word chunks */
+	PTR_ADDU a3,a0,a3	/* a3 is the dst address after loop */
+
+/* copying in words (4-byte or 8-byte chunks) */
+L(ua_wordCopy_loop):
+	C_LDHI	v1,UNIT(0)(a1)
+	C_LDLO	v1,UNITM1(1)(a1)
+	PTR_ADDIU a1,a1,UNIT(1)
+	PTR_ADDIU a0,a0,UNIT(1)
+	bne	a0,a3,L(ua_wordCopy_loop)
+	C_ST	v1,UNIT(-1)(a0)
+
+/* Copy the last 8 (or 16) bytes */
+L(ua_smallCopy):
+	beqz	a2,L(leave)
+	PTR_ADDU a3,a0,a2	/* a3 is the last dst address */
+L(ua_smallCopy_loop):
+	lb	v1,0(a1)
+	PTR_ADDIU a1,a1,1
+	PTR_ADDIU a0,a0,1
+	bne	a0,a3,L(ua_smallCopy_loop)
+	sb	v1,-1(a0)
+
+	j	ra
+	nop
+
+	.set	at
 	.set	reorder
-END (memcpy)
-libc_hidden_builtin_def (memcpy)
+END(MEMCPY_NAME)
+#ifdef _LIBC
+libc_hidden_builtin_def (MEMCPY_NAME)
+#endif
diff --git a/ports/sysdeps/mips/mips64/memcpy.S b/ports/sysdeps/mips/mips64/memcpy.S
deleted file mode 100644
index 49ef34d0c6..0000000000
--- a/ports/sysdeps/mips/mips64/memcpy.S
+++ /dev/null
@@ -1,138 +0,0 @@
-/* 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)