b6cbf7203b
This patch imports the unmodified current version of NetBSD libc. The NetBSD includes are in /nbsd_include, while the libc code itself is split between lib/nbsd_libc and common/lib/libc.
294 lines
6.6 KiB
ArmAsm
294 lines
6.6 KiB
ArmAsm
/* $NetBSD: bcopy.S,v 1.3 2009/12/14 00:39:00 matt Exp $ */
|
|
|
|
/*
|
|
* Mach Operating System
|
|
* Copyright (c) 1993 Carnegie Mellon University
|
|
* All Rights Reserved.
|
|
*
|
|
* Permission to use, copy, modify and distribute this software and its
|
|
* documentation is hereby granted, provided that both the copyright
|
|
* notice and this permission notice appear in all copies of the
|
|
* software, derivative works or modified versions, and any portions
|
|
* thereof, and that both notices appear in supporting documentation.
|
|
*
|
|
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
|
|
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
|
|
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
|
|
*
|
|
* Carnegie Mellon requests users of this software to return to
|
|
*
|
|
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
|
|
* School of Computer Science
|
|
* Carnegie Mellon University
|
|
* Pittsburgh PA 15213-3890
|
|
*
|
|
* any improvements or extensions that they make and grant Carnegie Mellon
|
|
* the rights to redistribute these changes.
|
|
*/
|
|
|
|
/*
|
|
* File: mips_bcopy.s
|
|
* Author: Chris Maeda
|
|
* Date: June 1993
|
|
*
|
|
* Fast copy routine. Derived from aligned_block_copy.
|
|
*/
|
|
|
|
|
|
#include <mips/asm.h>
|
|
#ifndef _LOCORE
|
|
#define _LOCORE /* XXX not really, just assembly-code source */
|
|
#endif
|
|
#include <machine/endian.h>
|
|
|
|
|
|
#if defined(LIBC_SCCS) && !defined(lint)
|
|
#if 0
|
|
RCSID("from: @(#)mips_bcopy.s 2.2 CMU 18/06/93")
|
|
#else
|
|
RCSID("$NetBSD: bcopy.S,v 1.3 2009/12/14 00:39:00 matt Exp $")
|
|
#endif
|
|
#endif /* LIBC_SCCS and not lint */
|
|
|
|
/*
|
|
* bcopy(caddr_t src, caddr_t dst, unsigned int len)
|
|
*
|
|
* a0 src address
|
|
* a1 dst address
|
|
* a2 length
|
|
*/
|
|
|
|
#if defined(MEMCOPY) || defined(MEMMOVE)
|
|
#ifdef MEMCOPY
|
|
#define FUNCTION memcpy
|
|
#else
|
|
#define FUNCTION memmove
|
|
#endif
|
|
#define SRCREG a1
|
|
#define DSTREG a0
|
|
#else
|
|
#define FUNCTION bcopy
|
|
#define SRCREG a0
|
|
#define DSTREG a1
|
|
#endif
|
|
|
|
#define SIZEREG a2
|
|
|
|
LEAF(FUNCTION)
|
|
.set noat
|
|
.set noreorder
|
|
|
|
#if defined(MEMCOPY) || defined(MEMMOVE)
|
|
/* set up return value, while we still can */
|
|
move v0,DSTREG
|
|
#endif
|
|
/*
|
|
* Make sure we can copy forwards.
|
|
*/
|
|
sltu t0,SRCREG,DSTREG # t0 == SRCREG < DSTREG
|
|
bne t0,zero,6f # copy backwards
|
|
|
|
/*
|
|
* There are four alignment cases (with frequency)
|
|
* (Based on measurements taken with a DECstation 5000/200
|
|
* inside a Mach kernel.)
|
|
*
|
|
* aligned -> aligned (mostly)
|
|
* unaligned -> aligned (sometimes)
|
|
* aligned,unaligned -> unaligned (almost never)
|
|
*
|
|
* Note that we could add another case that checks if
|
|
* the destination and source are unaligned but the
|
|
* copy is alignable. eg if src and dest are both
|
|
* on a halfword boundary.
|
|
*/
|
|
andi t1,DSTREG,(SZREG-1) # get last bits of dest
|
|
bne t1,zero,3f # dest unaligned
|
|
andi t0,SRCREG,(SZREG-1) # get last bits of src
|
|
bne t0,zero,5f
|
|
|
|
/*
|
|
* Forward aligned->aligned copy, 8 words at a time.
|
|
*/
|
|
98:
|
|
li AT,-(SZREG*8)
|
|
and t0,SIZEREG,AT # count truncated to multiples
|
|
PTR_ADDU a3,SRCREG,t0 # run fast loop up to this addr
|
|
sltu AT,SRCREG,a3 # any work to do?
|
|
beq AT,zero,2f
|
|
PTR_SUBU SIZEREG,t0
|
|
|
|
/*
|
|
* loop body
|
|
*/
|
|
1: # cp
|
|
REG_L t3,(0*SZREG)(SRCREG)
|
|
REG_L v1,(1*SZREG)(SRCREG)
|
|
REG_L t0,(2*SZREG)(SRCREG)
|
|
REG_L t1,(3*SZREG)(SRCREG)
|
|
PTR_ADDU SRCREG,SZREG*8
|
|
REG_S t3,(0*SZREG)(DSTREG)
|
|
REG_S v1,(1*SZREG)(DSTREG)
|
|
REG_S t0,(2*SZREG)(DSTREG)
|
|
REG_S t1,(3*SZREG)(DSTREG)
|
|
REG_L t1,(-1*SZREG)(SRCREG)
|
|
REG_L t0,(-2*SZREG)(SRCREG)
|
|
REG_L v1,(-3*SZREG)(SRCREG)
|
|
REG_L t3,(-4*SZREG)(SRCREG)
|
|
PTR_ADDU DSTREG,SZREG*8
|
|
REG_S t1,(-1*SZREG)(DSTREG)
|
|
REG_S t0,(-2*SZREG)(DSTREG)
|
|
REG_S v1,(-3*SZREG)(DSTREG)
|
|
bne SRCREG,a3,1b
|
|
REG_S t3,(-4*SZREG)(DSTREG)
|
|
|
|
/*
|
|
* Copy a word at a time, no loop unrolling.
|
|
*/
|
|
2: # wordcopy
|
|
andi t2,SIZEREG,(SZREG-1) # get byte count / SZREG
|
|
PTR_SUBU t2,SIZEREG,t2 # t2 = words to copy * SZREG
|
|
beq t2,zero,3f
|
|
PTR_ADDU t0,SRCREG,t2 # stop at t0
|
|
PTR_SUBU SIZEREG,SIZEREG,t2
|
|
1:
|
|
REG_L t3,0(SRCREG)
|
|
PTR_ADDU SRCREG,SZREG
|
|
REG_S t3,0(DSTREG)
|
|
bne SRCREG,t0,1b
|
|
PTR_ADDU DSTREG,SZREG
|
|
|
|
3: # bytecopy
|
|
beq SIZEREG,zero,4f # nothing left to do?
|
|
nop
|
|
1:
|
|
lb t3,0(SRCREG)
|
|
PTR_ADDU SRCREG,1
|
|
sb t3,0(DSTREG)
|
|
PTR_SUBU SIZEREG,1
|
|
bgtz SIZEREG,1b
|
|
PTR_ADDU DSTREG,1
|
|
|
|
4: # copydone
|
|
j ra
|
|
nop
|
|
|
|
/*
|
|
* Copy from unaligned source to aligned dest.
|
|
*/
|
|
5: # destaligned
|
|
andi t0,SIZEREG,(SZREG-1) # t0 = bytecount mod SZREG
|
|
PTR_SUBU a3,SIZEREG,t0 # number of words to transfer
|
|
beq a3,zero,3b
|
|
nop
|
|
move SIZEREG,t0 # this many to do after we are done
|
|
PTR_ADDU a3,SRCREG,a3 # stop point
|
|
|
|
1:
|
|
REG_LHI t3,0(SRCREG)
|
|
REG_LLO t3,SZREG-1(SRCREG)
|
|
PTR_ADDI SRCREG,SZREG
|
|
REG_S t3,0(DSTREG)
|
|
bne SRCREG,a3,1b
|
|
PTR_ADDI DSTREG,SZREG
|
|
|
|
b 3b
|
|
nop
|
|
|
|
6: # backcopy -- based on above
|
|
PTR_ADDU SRCREG,SIZEREG
|
|
PTR_ADDU DSTREG,SIZEREG
|
|
andi t1,DSTREG,SZREG-1 # get last 3 bits of dest
|
|
bne t1,zero,3f
|
|
andi t0,SRCREG,SZREG-1 # get last 3 bits of src
|
|
bne t0,zero,5f
|
|
|
|
/*
|
|
* Forward aligned->aligned copy, 8*4 bytes at a time.
|
|
*/
|
|
li AT,(-8*SZREG)
|
|
and t0,SIZEREG,AT # count truncated to multiple of 32
|
|
beq t0,zero,2f # any work to do?
|
|
PTR_SUBU SIZEREG,t0
|
|
PTR_SUBU a3,SRCREG,t0
|
|
|
|
/*
|
|
* loop body
|
|
*/
|
|
1: # cp
|
|
REG_L t3,(-4*SZREG)(SRCREG)
|
|
REG_L v1,(-3*SZREG)(SRCREG)
|
|
REG_L t0,(-2*SZREG)(SRCREG)
|
|
REG_L t1,(-1*SZREG)(SRCREG)
|
|
PTR_SUBU SRCREG,8*SZREG
|
|
REG_S t3,(-4*SZREG)(DSTREG)
|
|
REG_S v1,(-3*SZREG)(DSTREG)
|
|
REG_S t0,(-2*SZREG)(DSTREG)
|
|
REG_S t1,(-1*SZREG)(DSTREG)
|
|
REG_L t1,(3*SZREG)(SRCREG)
|
|
REG_L t0,(2*SZREG)(SRCREG)
|
|
REG_L v1,(1*SZREG)(SRCREG)
|
|
REG_L t3,(0*SZREG)(SRCREG)
|
|
PTR_SUBU DSTREG,8*SZREG
|
|
REG_S t1,(3*SZREG)(DSTREG)
|
|
REG_S t0,(2*SZREG)(DSTREG)
|
|
REG_S v1,(1*SZREG)(DSTREG)
|
|
bne SRCREG,a3,1b
|
|
REG_S t3,(0*SZREG)(DSTREG)
|
|
|
|
/*
|
|
* Copy a word at a time, no loop unrolling.
|
|
*/
|
|
2: # wordcopy
|
|
andi t2,SIZEREG,SZREG-1 # get byte count / 4
|
|
PTR_SUBU t2,SIZEREG,t2 # t2 = number of words to copy
|
|
beq t2,zero,3f
|
|
PTR_SUBU t0,SRCREG,t2 # stop at t0
|
|
PTR_SUBU SIZEREG,SIZEREG,t2
|
|
1:
|
|
REG_L t3,-SZREG(SRCREG)
|
|
PTR_SUBU SRCREG,SZREG
|
|
REG_S t3,-SZREG(DSTREG)
|
|
bne SRCREG,t0,1b
|
|
PTR_SUBU DSTREG,SZREG
|
|
|
|
3: # bytecopy
|
|
beq SIZEREG,zero,4f # nothing left to do?
|
|
nop
|
|
1:
|
|
lb t3,-1(SRCREG)
|
|
PTR_SUBU SRCREG,1
|
|
sb t3,-1(DSTREG)
|
|
PTR_SUBU SIZEREG,1
|
|
bgtz SIZEREG,1b
|
|
PTR_SUBU DSTREG,1
|
|
|
|
4: # copydone
|
|
j ra
|
|
nop
|
|
|
|
/*
|
|
* Copy from unaligned source to aligned dest.
|
|
*/
|
|
5: # destaligned
|
|
andi t0,SIZEREG,SZREG-1 # t0 = bytecount mod 4
|
|
PTR_SUBU a3,SIZEREG,t0 # number of words to transfer
|
|
beq a3,zero,3b
|
|
nop
|
|
move SIZEREG,t0 # this many to do after we are done
|
|
PTR_SUBU a3,SRCREG,a3 # stop point
|
|
|
|
1:
|
|
REG_LHI t3,-SZREG(SRCREG)
|
|
REG_LLO t3,-1(SRCREG)
|
|
PTR_SUBU SRCREG,SZREG
|
|
REG_S t3,-SZREG(DSTREG)
|
|
bne SRCREG,a3,1b
|
|
PTR_SUBU DSTREG,SZREG
|
|
|
|
b 3b
|
|
nop
|
|
|
|
.set reorder
|
|
.set at
|
|
END(FUNCTION)
|