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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 | /* memcpy.S: optimised assembly memcpy * * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ .text .p2align 4 ############################################################################### # # void *memcpy(void *to, const char *from, size_t count) # # - NOTE: must not use any stack. exception detection performs function return # to caller's fixup routine, aborting the remainder of the copy # ############################################################################### .globl memcpy,__memcpy_end .type memcpy,@function memcpy: or.p gr8,gr9,gr4 orcc gr10,gr0,gr0,icc3 or.p gr10,gr4,gr4 beqlr icc3,#0 # optimise based on best common alignment for to, from & count andicc.p gr4,#0x0f,gr0,icc0 setlos #8,gr11 andicc.p gr4,#0x07,gr0,icc1 beq icc0,#0,memcpy_16 andicc.p gr4,#0x03,gr0,icc0 beq icc1,#0,memcpy_8 andicc.p gr4,#0x01,gr0,icc1 beq icc0,#0,memcpy_4 setlos.p #1,gr11 beq icc1,#0,memcpy_2 # do byte by byte copy sub.p gr8,gr11,gr3 sub gr9,gr11,gr9 0: ldubu.p @(gr9,gr11),gr4 subicc gr10,#1,gr10,icc0 stbu.p gr4,@(gr3,gr11) bne icc0,#2,0b bralr # do halfword by halfword copy memcpy_2: setlos #2,gr11 sub.p gr8,gr11,gr3 sub gr9,gr11,gr9 0: lduhu.p @(gr9,gr11),gr4 subicc gr10,#2,gr10,icc0 sthu.p gr4,@(gr3,gr11) bne icc0,#2,0b bralr # do word by word copy memcpy_4: setlos #4,gr11 sub.p gr8,gr11,gr3 sub gr9,gr11,gr9 0: ldu.p @(gr9,gr11),gr4 subicc gr10,#4,gr10,icc0 stu.p gr4,@(gr3,gr11) bne icc0,#2,0b bralr # do double-word by double-word copy memcpy_8: sub.p gr8,gr11,gr3 sub gr9,gr11,gr9 0: lddu.p @(gr9,gr11),gr4 subicc gr10,#8,gr10,icc0 stdu.p gr4,@(gr3,gr11) bne icc0,#2,0b bralr # do quad-word by quad-word copy memcpy_16: sub.p gr8,gr11,gr3 sub gr9,gr11,gr9 0: lddu @(gr9,gr11),gr4 lddu.p @(gr9,gr11),gr6 subicc gr10,#16,gr10,icc0 stdu gr4,@(gr3,gr11) stdu.p gr6,@(gr3,gr11) bne icc0,#2,0b bralr __memcpy_end: .size memcpy, __memcpy_end-memcpy ############################################################################### # # copy to/from userspace # - return the number of bytes that could not be copied (0 on complete success) # # long __memcpy_user(void *dst, const void *src, size_t count) # ############################################################################### .globl __memcpy_user, __memcpy_user_error_lr, __memcpy_user_error_handler .type __memcpy_user,@function __memcpy_user: movsg lr,gr7 subi.p sp,#8,sp add gr8,gr10,gr6 ; calculate expected end address stdi gr6,@(sp,#0) # abuse memcpy to do the dirty work call memcpy __memcpy_user_error_lr: ldi.p @(sp,#4),gr7 setlos #0,gr8 jmpl.p @(gr7,gr0) addi sp,#8,sp # deal any exception generated by memcpy # GR8 - memcpy's current dest address # GR11 - memset's step value (index register for store insns) __memcpy_user_error_handler: lddi.p @(sp,#0),gr4 ; load GR4 with dst+count, GR5 with ret addr add gr11,gr3,gr7 sub.p gr4,gr7,gr8 addi sp,#8,sp jmpl @(gr5,gr0) .size __memcpy_user, .-__memcpy_user |