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-rw-r--r--sysdeps/mips/memcpy.S677
1 files changed, 677 insertions, 0 deletions
diff --git a/sysdeps/mips/memcpy.S b/sysdeps/mips/memcpy.S
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+/* Copyright (C) 2012-2014 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   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/>.  */
+
+#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_PREPAREFORSTORE
+#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_PREPAREFORSTORE
+#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 defined(_MIPS_SIM) && ((_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.
+ */
+
+#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)*64(reg); \
+ pref PREFETCH_LOAD_HINT, ((chunk)*64)+32(reg)
+# define PREFETCH_FOR_STORE(chunk, reg) \
+ pref PREFETCH_STORE_HINT, (chunk)*64(reg); \
+ pref PREFETCH_STORE_HINT, ((chunk)*64)+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
+/* MAX_PREFETCH_SIZE is the maximum size of a prefetch, it must not be less
+ * than PREFETCH_CHUNK, the assumed size of each prefetch.  If the real size
+ * of a prefetch is greater than MAX_PREFETCH_SIZE and the PREPAREFORSTORE
+ * hint is used, the code will not work correctly.  If PREPAREFORSTORE is not
+ * used then MAX_PREFETCH_SIZE does not matter.  */
+#define MAX_PREFETCH_SIZE 128
+/* PREFETCH_LIMIT is set based on the fact that we never use an offset greater
+ * than 5 on a STORE prefetch and that a single prefetch can never be larger
+ * than MAX_PREFETCH_SIZE.  We add the extra 32 when USE_DOUBLE is set because
+ * we actually do two prefetches in that case, one 32 bytes after the other.  */
+#ifdef USE_DOUBLE
+# define PREFETCH_LIMIT (5 * PREFETCH_CHUNK) + 32 + MAX_PREFETCH_SIZE
+#else
+# define PREFETCH_LIMIT (5 * PREFETCH_CHUNK) + MAX_PREFETCH_SIZE
+#endif
+#if (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE) \
+    && ((PREFETCH_CHUNK * 4) < MAX_PREFETCH_SIZE)
+/* We cannot handle this because the initial prefetches may fetch bytes that
+ * are before the buffer being copied.  We start copies with an offset
+ * of 4 so avoid this situation when using PREPAREFORSTORE.  */
+#error "PREFETCH_CHUNK is too large and/or MAX_PREFETCH_SIZE is too small."
+#endif
+#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 defined(_MIPS_SIM) && ((_MIPS_SIM == _ABIO32) || (_MIPS_SIM == _ABIO64))
+#  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 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 NSIZE 4
+#  define NSIZEMASK 0x1f
+#  define NSIZEDMASK 0x3f
+#endif
+#define UNIT(unit) ((unit)*NSIZE)
+#define UNITM1(unit) (((unit)*NSIZE)-1)
+
+#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 than 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)
+#if defined(RETURN_FIRST_PREFETCH) || defined(RETURN_LAST_PREFETCH)
+	move	v0,zero
+#else
+	move	v0,a0
+#endif
+/*
+ * 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_LOAD  (3, a1)
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT != PREFETCH_HINT_PREPAREFORSTORE)
+	PREFETCH_FOR_STORE (1, a0)
+	PREFETCH_FOR_STORE (2, a0)
+	PREFETCH_FOR_STORE (3, a0)
+#endif
+#if defined(RETURN_FIRST_PREFETCH) && defined(USE_PREFETCH)
+#if PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE
+	sltu    v1,t9,a0
+	bgtz    v1,L(skip_set)
+	nop
+	PTR_ADDIU v0,a0,(PREFETCH_CHUNK*4)
+L(skip_set):
+#else
+	PTR_ADDIU v0,a0,(PREFETCH_CHUNK*1)
+#endif
+#endif
+#if defined(RETURN_LAST_PREFETCH) && defined(USE_PREFETCH) \
+    && (PREFETCH_STORE_HINT != PREFETCH_HINT_PREPAREFORSTORE)
+	PTR_ADDIU v0,a0,(PREFETCH_CHUNK*3)
+#ifdef USE_DOUBLE
+	PTR_ADDIU v0,v0,32
+#endif
+#endif
+L(loop16w):
+	C_LD	t0,UNIT(0)(a1)
+#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(skip_pref)
+#endif
+	C_LD	t1,UNIT(1)(a1)
+	PREFETCH_FOR_STORE (4, a0)
+	PREFETCH_FOR_STORE (5, a0)
+#if defined(RETURN_LAST_PREFETCH) && defined(USE_PREFETCH)
+	PTR_ADDIU v0,a0,(PREFETCH_CHUNK*5)
+#ifdef USE_DOUBLE
+	PTR_ADDIU v0,v0,32
+#endif
+#endif
+L(skip_pref):
+	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)
+	C_LD	t1,UNIT(9)(a1)
+	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 */
+	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 than 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 a0,a0,UNIT(1)
+	PTR_ADDIU a1,a1,UNIT(1)
+	bne	a0,a3,L(wordCopy_loop)
+	C_ST	REG3,UNIT(-1)(a0)
+
+/* 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 a0,a0,1
+	PTR_ADDIU a1,a1,1
+	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(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)
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT != PREFETCH_HINT_PREPAREFORSTORE)
+	PREFETCH_FOR_STORE (1, a0)
+	PREFETCH_FOR_STORE (2, a0)
+	PREFETCH_FOR_STORE (3, a0)
+#endif
+#if defined(RETURN_FIRST_PREFETCH) && defined(USE_PREFETCH)
+#if (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
+	sltu    v1,t9,a0
+	bgtz    v1,L(ua_skip_set)
+	nop
+	PTR_ADDIU v0,a0,(PREFETCH_CHUNK*4)
+L(ua_skip_set):
+#else
+	PTR_ADDIU v0,a0,(PREFETCH_CHUNK*1)
+#endif
+#endif
+L(ua_loop16w):
+	PREFETCH_FOR_LOAD  (3, a1)
+	C_LDHI	t0,UNIT(0)(a1)
+	C_LDHI	t1,UNIT(1)(a1)
+	C_LDHI	REG2,UNIT(2)(a1)
+#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
+	sltu	v1,t9,a0
+	bgtz	v1,L(ua_skip_pref)
+#endif
+	C_LDHI	REG3,UNIT(3)(a1)
+	PREFETCH_FOR_STORE (4, a0)
+	PREFETCH_FOR_STORE (5, a0)
+L(ua_skip_pref):
+	C_LDHI	REG4,UNIT(4)(a1)
+	C_LDHI	REG5,UNIT(5)(a1)
+	C_LDHI	REG6,UNIT(6)(a1)
+	C_LDHI	REG7,UNIT(7)(a1)
+	C_LDLO	t0,UNITM1(1)(a1)
+	C_LDLO	t1,UNITM1(2)(a1)
+	C_LDLO	REG2,UNITM1(3)(a1)
+	C_LDLO	REG3,UNITM1(4)(a1)
+	C_LDLO	REG4,UNITM1(5)(a1)
+	C_LDLO	REG5,UNITM1(6)(a1)
+	C_LDLO	REG6,UNITM1(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_LDHI	t1,UNIT(9)(a1)
+	C_LDHI	REG2,UNIT(10)(a1)
+	C_LDHI	REG3,UNIT(11)(a1)
+	C_LDHI	REG4,UNIT(12)(a1)
+	C_LDHI	REG5,UNIT(13)(a1)
+	C_LDHI	REG6,UNIT(14)(a1)
+	C_LDHI	REG7,UNIT(15)(a1)
+	C_LDLO	t0,UNITM1(9)(a1)
+	C_LDLO	t1,UNITM1(10)(a1)
+	C_LDLO	REG2,UNITM1(11)(a1)
+	C_LDLO	REG3,UNITM1(12)(a1)
+	C_LDLO	REG4,UNITM1(13)(a1)
+	C_LDLO	REG5,UNITM1(14)(a1)
+	C_LDLO	REG6,UNITM1(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 */
+	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_LDHI	t1,UNIT(1)(a1)
+	C_LDHI	REG2,UNIT(2)(a1)
+	C_LDHI	REG3,UNIT(3)(a1)
+	C_LDHI	REG4,UNIT(4)(a1)
+	C_LDHI	REG5,UNIT(5)(a1)
+	C_LDHI	REG6,UNIT(6)(a1)
+	C_LDHI	REG7,UNIT(7)(a1)
+	C_LDLO	t0,UNITM1(1)(a1)
+	C_LDLO	t1,UNITM1(2)(a1)
+	C_LDLO	REG2,UNITM1(3)(a1)
+	C_LDLO	REG3,UNITM1(4)(a1)
+	C_LDLO	REG4,UNITM1(5)(a1)
+	C_LDLO	REG5,UNITM1(6)(a1)
+	C_LDLO	REG6,UNITM1(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 than 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 a0,a0,UNIT(1)
+	PTR_ADDIU a1,a1,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 a0,a0,1
+	PTR_ADDIU a1,a1,1
+	bne	a0,a3,L(ua_smallCopy_loop)
+	sb	v1,-1(a0)
+
+	j	ra
+	nop
+
+	.set	at
+	.set	reorder
+END(MEMCPY_NAME)
+#ifndef ANDROID_CHANGES
+#ifdef _LIBC
+libc_hidden_builtin_def (MEMCPY_NAME)
+#endif
+#endif