1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * linux/arch/alpha/lib/memset.S 4 * 5 * This is an efficient (and small) implementation of the C library "memset()" 6 * function for the alpha. 7 * 8 * (C) Copyright 1996 Linus Torvalds 9 * 10 * This routine is "moral-ware": you are free to use it any way you wish, and 11 * the only obligation I put on you is a moral one: if you make any improvements 12 * to the routine, please send me your improvements for me to use similarly. 13 * 14 * The scheduling comments are according to the EV5 documentation (and done by 15 * hand, so they might well be incorrect, please do tell me about it..) 16 */ 17 #include <linux/export.h> 18 .set noat 19 .set noreorder 20 .text 21 .globl memset 22 .globl __memset 23 .globl ___memset 24 .globl __memset16 25 .globl __constant_c_memset 26 27 .ent ___memset 28 .align 5 29 ___memset: 30 .frame $30,0,$26,0 31 .prologue 0 32 33 and $17,255,$1 /* E1 */ 34 insbl $17,1,$17 /* .. E0 */ 35 bis $17,$1,$17 /* E0 (p-c latency, next cycle) */ 36 sll $17,16,$1 /* E1 (p-c latency, next cycle) */ 37 38 bis $17,$1,$17 /* E0 (p-c latency, next cycle) */ 39 sll $17,32,$1 /* E1 (p-c latency, next cycle) */ 40 bis $17,$1,$17 /* E0 (p-c latency, next cycle) */ 41 ldq_u $31,0($30) /* .. E1 */ 42 43 .align 5 44 __constant_c_memset: 45 addq $18,$16,$6 /* E0 */ 46 bis $16,$16,$0 /* .. E1 */ 47 xor $16,$6,$1 /* E0 */ 48 ble $18,end /* .. E1 */ 49 50 bic $1,7,$1 /* E0 */ 51 beq $1,within_one_quad /* .. E1 (note EV5 zero-latency forwarding) */ 52 and $16,7,$3 /* E0 */ 53 beq $3,aligned /* .. E1 (note EV5 zero-latency forwarding) */ 54 55 ldq_u $4,0($16) /* E0 */ 56 bis $16,$16,$5 /* .. E1 */ 57 insql $17,$16,$2 /* E0 */ 58 subq $3,8,$3 /* .. E1 */ 59 60 addq $18,$3,$18 /* E0 $18 is new count ($3 is negative) */ 61 mskql $4,$16,$4 /* .. E1 (and possible load stall) */ 62 subq $16,$3,$16 /* E0 $16 is new aligned destination */ 63 bis $2,$4,$1 /* .. E1 */ 64 65 bis $31,$31,$31 /* E0 */ 66 ldq_u $31,0($30) /* .. E1 */ 67 stq_u $1,0($5) /* E0 */ 68 bis $31,$31,$31 /* .. E1 */ 69 70 .align 4 71 aligned: 72 sra $18,3,$3 /* E0 */ 73 and $18,7,$18 /* .. E1 */ 74 bis $16,$16,$5 /* E0 */ 75 beq $3,no_quad /* .. E1 */ 76 77 .align 3 78 loop: 79 stq $17,0($5) /* E0 */ 80 subq $3,1,$3 /* .. E1 */ 81 addq $5,8,$5 /* E0 */ 82 bne $3,loop /* .. E1 */ 83 84 no_quad: 85 bis $31,$31,$31 /* E0 */ 86 beq $18,end /* .. E1 */ 87 ldq $7,0($5) /* E0 */ 88 mskqh $7,$6,$2 /* .. E1 (and load stall) */ 89 90 insqh $17,$6,$4 /* E0 */ 91 bis $2,$4,$1 /* .. E1 */ 92 stq $1,0($5) /* E0 */ 93 ret $31,($26),1 /* .. E1 */ 94 95 .align 3 96 within_one_quad: 97 ldq_u $1,0($16) /* E0 */ 98 insql $17,$16,$2 /* E1 */ 99 mskql $1,$16,$4 /* E0 (after load stall) */ 100 bis $2,$4,$2 /* E0 */ 101 102 mskql $2,$6,$4 /* E0 */ 103 mskqh $1,$6,$2 /* .. E1 */ 104 bis $2,$4,$1 /* E0 */ 105 stq_u $1,0($16) /* E0 */ 106 107 end: 108 ret $31,($26),1 /* E1 */ 109 .end ___memset 110 EXPORT_SYMBOL(___memset) 111 EXPORT_SYMBOL(__constant_c_memset) 112 113 .align 5 114 .ent __memset16 115 __memset16: 116 .prologue 0 117 118 inswl $17,0,$1 /* E0 */ 119 inswl $17,2,$2 /* E0 */ 120 inswl $17,4,$3 /* E0 */ 121 or $1,$2,$1 /* .. E1 */ 122 inswl $17,6,$4 /* E0 */ 123 or $1,$3,$1 /* .. E1 */ 124 or $1,$4,$17 /* E0 */ 125 br __constant_c_memset /* .. E1 */ 126 127 .end __memset16 128 EXPORT_SYMBOL(__memset16) 129 130 memset = ___memset 131 __memset = ___memset 132 EXPORT_SYMBOL(memset) 133 EXPORT_SYMBOL(__memset) 134