/* $OpenBSD: copy_subr.S,v 1.8 2025/07/19 05:23:37 miod Exp $ */ /* * Mach Operating System * Copyright (c) 1993-1992 Carnegie Mellon University * Copyright (c) 1991 OMRON Corporation * Copyright (c) 1996 Nivas Madhur * Copyright (c) 1998 Steve Murphree, Jr. * 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 AND OMRON ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON AND OMRON DISCLAIM 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 the * rights to redistribute these changes. */ #include <machine/asm.h> /* * copy count bytes of data from source to destination * Don Harper (don@omron.co.jp), Omron Corporation. */ #if defined(MEMCPY) || defined(MEMMOVE) #define SRC %r3 #define DEST %r2 #define SAVE %r5 #else #define SRC %r2 #define DEST %r3 #endif #define LEN %r4 #ifdef MEMCPY ENTRY(memcpy) #endif #ifdef MEMMOVE ENTRY(memmove) #endif #ifdef BCOPY #define OVBCOPY ENTRY(bcopy) #endif #if defined(MEMCPY) || defined(MEMMOVE) or SAVE, DEST, %r0 #endif bcnd eq0,LEN,bcopy_out /* nothing to do if == 0 */ /* * check position of source and destination data */ cmp %r9,SRC,DEST /* compare source address to destination */ bb1 eq,%r9,bcopy_out /* nothing to do if equal */ #if defined(MEMMOVE) || defined(OVBCOPY) bb1 lo,%r9,bcopy_reverse /* reverse copy if src < dest */ #endif /* * source address is greater than destination address, or we do * not have to care about overlapping areas: copy forward */ cmp %r9,LEN,16 /* see if we have at least 16 bytes */ bb1 lt,%r9,f_byte_copy /* copy bytes for small data length */ /* * determine copy strategy based on alignment of source and destination */ mask %r6,SRC,3 /* get 2 low order bits of source address */ mask %r7,DEST,3 /* get 2 low order bits of destination addr */ mak %r6,%r6,0<4> /* convert source bits to table offset */ mak %r7,%r7,0<2> /* convert destination bits to table offset */ or.u %r12,%r0,%hi16(f_strat) or %r12,%r12,%lo16(f_strat) addu %r6,%r6,%r7 /* compute final table offset for strategy */ ld %r12,%r12,%r6 /* load the strategy routine */ jmp %r12 /* branch to strategy routine */ /* * Copy three bytes from src to destination then copy words */ ASLOCAL(f_3byte_word_copy) ld.bu %r6,SRC,0 /* load byte from source */ ld.bu %r7,SRC,1 /* load byte from source */ ld.bu %r8,SRC,2 /* load byte from source */ st.b %r6,DEST,0 /* store byte to destination */ st.b %r7,DEST,1 /* store byte to destination */ st.b %r8,DEST,2 /* store byte to destination */ addu SRC,SRC,3 /* increment source pointer */ addu DEST,DEST,3 /* increment destination pointer */ br.n f_word_copy /* copy full words */ subu LEN,LEN,3 /* decrement length */ /* * Copy 1 halfword from src to destination then copy words */ ASLOCAL(f_1half_word_copy) ld.hu %r6,SRC,0 /* load half-word from source */ st.h %r6,DEST,0 /* store half-word to destination */ addu SRC,SRC,2 /* increment source pointer */ addu DEST,DEST,2 /* increment destination pointer */ br.n f_word_copy /* copy full words */ subu LEN,LEN,2 /* decrement remaining length */ /* * Copy 1 byte from src to destination then copy words */ ASLOCAL(f_1byte_word_copy) ld.bu %r6,SRC,0 /* load 1 byte from source */ st.b %r6,DEST,0 /* store 1 byte to destination */ addu SRC,SRC,1 /* increment source pointer */ addu DEST,DEST,1 /* increment destination pointer */ subu LEN,LEN,1 /* decrement remaining length */ /* FALLTHROUGH */ /* * Copy as many full words as possible, 4 words per loop */ ASLOCAL(f_word_copy) cmp %r10,LEN,16 /* see if we have 16 bytes remaining */ bb1 lo,%r10,f_byte_copy /* not enough left, copy bytes */ ld %r6,SRC,0 /* load first word */ ld %r7,SRC,4 /* load second word */ ld %r8,SRC,8 /* load third word */ ld %r9,SRC,12 /* load fourth word */ st %r6,DEST,0 /* store first word */ st %r7,DEST,4 /* store second word */ st %r8,DEST,8 /* store third word */ st %r9,DEST,12 /* store fourth word */ addu SRC,SRC,16 /* increment source pointer */ addu DEST,DEST,16 /* increment destination pointer */ br.n f_word_copy /* branch to copy another block */ subu LEN,LEN,16 /* decrement remaining length */ ASLOCAL(f_1byte_half_copy) ld.bu %r6,SRC,0 /* load 1 byte from source */ st.b %r6,DEST,0 /* store 1 byte to destination */ addu SRC,SRC,1 /* increment source pointer */ addu DEST,DEST,1 /* increment destination pointer */ subu LEN,LEN,1 /* decrement remaining length */ /* FALLTHROUGH */ ASLOCAL(f_half_copy) cmp %r10,LEN,16 /* see if we have 16 bytes remaining */ bb1 lo,%r10,f_byte_copy /* not enough left, copy bytes */ ld.hu %r6,SRC,0 /* load first half-word */ ld.hu %r7,SRC,2 /* load second half-word */ ld.hu %r8,SRC,4 /* load third half-word */ ld.hu %r9,SRC,6 /* load fourth half-word */ ld.hu %r10,SRC,8 /* load fifth half-word */ ld.hu %r11,SRC,10 /* load sixth half-word */ ld.hu %r12,SRC,12 /* load seventh half-word */ ld.hu %r13,SRC,14 /* load eighth half-word */ st.h %r6,DEST,0 /* store first half-word */ st.h %r7,DEST,2 /* store second half-word */ st.h %r8,DEST,4 /* store third half-word */ st.h %r9,DEST,6 /* store fourth half-word */ st.h %r10,DEST,8 /* store fifth half-word */ st.h %r11,DEST,10 /* store sixth half-word */ st.h %r12,DEST,12 /* store seventh half-word */ st.h %r13,DEST,14 /* store eighth half-word */ addu SRC,SRC,16 /* increment source pointer */ addu DEST,DEST,16 /* increment destination pointer */ br.n f_half_copy /* branch to copy another block */ subu LEN,LEN,16 /* decrement remaining length */ ASLOCAL(f_byte_copy) bcnd eq0,LEN,bcopy_out /* branch if nothing left to copy */ ld.bu %r6,SRC,0 /* load byte from source */ st.b %r6,DEST,0 /* store byte in destination */ addu SRC,SRC,1 /* increment source pointer */ addu DEST,DEST,1 /* increment destination pointer */ br.n f_byte_copy /* branch for next byte */ subu LEN,LEN,1 /* decrement remaining length */ #if defined(MEMMOVE) || defined(OVBCOPY) /* * source address is less than destination address, copy in reverse */ ASLOCAL(bcopy_reverse) /* * start copy pointers at end of data */ addu SRC,SRC,LEN /* start source at end of data */ addu DEST,DEST,LEN /* start destination at end of data */ /* * check for short data */ cmp %r9,LEN,16 /* see if we have at least 16 bytes */ bb1 lt,%r9,r_byte_copy /* copy bytes for small data length */ /* * determine copy strategy based on alignment of source and destination */ mask %r6,SRC,3 /* get 2 low order bits of source address */ mask %r7,DEST,3 /* get 2 low order bits of destination addr */ mak %r6,%r6,0<4> /* convert source bits to table offset */ mak %r7,%r7,0<2> /* convert destination bits to table offset */ or.u %r12,%r0,%hi16(r_strat) or %r12,%r12,%lo16(r_strat) addu %r6,%r6,%r7 /* compute final table offset for strategy */ ld %r12,%r12,%r6 /* load the strategy routine */ jmp %r12 /* branch to strategy routine */ /* * Copy three bytes from src to destination then copy words */ ASLOCAL(r_3byte_word_copy) subu SRC,SRC,3 /* decrement source pointer */ subu DEST,DEST,3 /* decrement destination pointer */ ld.bu %r6,SRC,0 /* load byte from source */ ld.bu %r7,SRC,1 /* load byte from source */ ld.bu %r8,SRC,2 /* load byte from source */ st.b %r6,DEST,0 /* store byte to destination */ st.b %r7,DEST,1 /* store byte to destination */ st.b %r8,DEST,2 /* store byte to destination */ br.n r_word_copy /* copy full words */ subu LEN,LEN,3 /* decrement length */ /* * Copy 1 halfword from src to destination then copy words */ ASLOCAL(r_1half_word_copy) subu SRC,SRC,2 /* decrement source pointer */ subu DEST,DEST,2 /* decrement destination pointer */ ld.hu %r6,SRC,0 /* load half-word from source */ st.h %r6,DEST,0 /* store half-word to destination */ br.n r_word_copy /* copy full words */ subu LEN,LEN,2 /* decrement remaining length */ /* * Copy 1 byte from src to destination then copy words */ ASLOCAL(r_1byte_word_copy) subu SRC,SRC,1 /* decrement source pointer */ subu DEST,DEST,1 /* decrement destination pointer */ ld.bu %r6,SRC,0 /* load 1 byte from source */ st.b %r6,DEST,0 /* store 1 byte to destination */ subu LEN,LEN,1 /* decrement remaining length */ /* FALLTHROUGH */ /* * Copy as many full words as possible, 4 words per loop */ ASLOCAL(r_word_copy) cmp %r10,LEN,16 /* see if we have 16 bytes remaining */ bb1 lo,%r10,r_byte_copy /* not enough left, copy bytes */ subu SRC,SRC,16 /* decrement source pointer */ subu DEST,DEST,16 /* decrement destination pointer */ ld %r6,SRC,0 /* load first word */ ld %r7,SRC,4 /* load second word */ ld %r8,SRC,8 /* load third word */ ld %r9,SRC,12 /* load fourth word */ st %r6,DEST,0 /* store first word */ st %r7,DEST,4 /* store second word */ st %r8,DEST,8 /* store third word */ st %r9,DEST,12 /* store fourth word */ br.n r_word_copy /* branch to copy another block */ subu LEN,LEN,16 /* decrement remaining length */ ASLOCAL(r_1byte_half_copy) subu SRC,SRC,1 /* decrement source pointer */ subu DEST,DEST,1 /* decrement destination pointer */ ld.bu %r6,SRC,0 /* load 1 byte from source */ st.b %r6,DEST,0 /* store 1 byte to destination */ subu LEN,LEN,1 /* decrement remaining length */ /* FALLTHROUGH */ ASLOCAL(r_half_copy) cmp %r10,LEN,16 /* see if we have 16 bytes remaining */ bb1 lo,%r10,r_byte_copy /* not enough left, copy bytes */ subu SRC,SRC,16 /* decrement source pointer */ subu DEST,DEST,16 /* decrement destination pointer */ ld.hu %r6,SRC,0 /* load first half-word */ ld.hu %r7,SRC,2 /* load second half-word */ ld.hu %r8,SRC,4 /* load third half-word */ ld.hu %r9,SRC,6 /* load fourth half-word */ ld.hu %r10,SRC,8 /* load fifth half-word */ ld.hu %r11,SRC,10 /* load sixth half-word */ ld.hu %r12,SRC,12 /* load seventh half-word */ ld.hu %r13,SRC,14 /* load eighth half-word */ st.h %r6,DEST,0 /* store first half-word */ st.h %r7,DEST,2 /* store second half-word */ st.h %r8,DEST,4 /* store third half-word */ st.h %r9,DEST,6 /* store fourth half-word */ st.h %r10,DEST,8 /* store fifth half-word */ st.h %r11,DEST,10 /* store sixth half-word */ st.h %r12,DEST,12 /* store seventh half-word */ st.h %r13,DEST,14 /* store eighth half-word */ br.n r_half_copy /* branch to copy another block */ subu LEN,LEN,16 /* decrement remaining length */ ASLOCAL(r_byte_copy) bcnd eq0,LEN,bcopy_out /* branch if nothing left to copy */ subu SRC,SRC,1 /* decrement source pointer */ subu DEST,DEST,1 /* decrement destination pointer */ ld.bu %r6,SRC,0 /* load byte from source */ st.b %r6,DEST,0 /* store byte in destination */ br.n r_byte_copy /* branch for next byte */ subu LEN,LEN,1 /* decrement remaining length */ #endif /* MEMMOVE || OVBCOPY */ ASLOCAL(bcopy_out) #if defined(MEMCPY) || defined(MEMMOVE) jmp.n %r1 /* all done, return to caller */ or %r2, SAVE, %r0 #else jmp %r1 /* all done, return to caller */ #endif .section .rodata .align 2 ASLOCAL(f_strat) .word f_word_copy .word f_byte_copy .word f_half_copy .word f_byte_copy .word f_byte_copy .word f_3byte_word_copy .word f_byte_copy .word f_1byte_half_copy .word f_half_copy .word f_byte_copy .word f_1half_word_copy .word f_byte_copy .word f_byte_copy .word f_1byte_half_copy .word f_byte_copy .word f_1byte_word_copy #if defined(MEMMOVE) || defined(OVBCOPY) ASLOCAL(r_strat) .word r_word_copy .word r_byte_copy .word r_half_copy .word r_byte_copy .word r_byte_copy .word r_1byte_word_copy .word r_byte_copy .word r_1byte_half_copy .word r_half_copy .word r_byte_copy .word r_1half_word_copy .word r_byte_copy .word r_byte_copy .word r_1byte_half_copy .word r_byte_copy .word r_3byte_word_copy #endif
