1/* 2 * File: arch/blackfin/lib/memmove.S 3 * Based on: 4 * Author: 5 * 6 * Created: 7 * Description: 8 * 9 * Modified: 10 * Copyright 2004-2006 Analog Devices Inc. 11 * 12 * Bugs: Enter bugs at http://blackfin.uclinux.org/ 13 * 14 * This program is free software; you can redistribute it and/or modify 15 * it under the terms of the GNU General Public License as published by 16 * the Free Software Foundation; either version 2 of the License, or 17 * (at your option) any later version. 18 * 19 * This program is distributed in the hope that it will be useful, 20 * but WITHOUT ANY WARRANTY; without even the implied warranty of 21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 22 * GNU General Public License for more details. 23 * 24 * You should have received a copy of the GNU General Public License 25 * along with this program; if not, see the file COPYING, or write 26 * to the Free Software Foundation, Inc., 27 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 28 */ 29 30#include <linux/linkage.h> 31 32.align 2 33 34/* 35 * C Library function MEMMOVE 36 * R0 = To Address (leave unchanged to form result) 37 * R1 = From Address 38 * R2 = count 39 * Data may overlap 40 */ 41 42ENTRY(_memmove) 43 I1 = P3; 44 P0 = R0; /* P0 = To address */ 45 P3 = R1; /* P3 = From Address */ 46 P2 = R2; /* P2 = count */ 47 CC = P2 == 0; /* Check zero count*/ 48 IF CC JUMP .Lfinished; /* very unlikely */ 49 50 CC = R1 < R0 (IU); /* From < To */ 51 IF !CC JUMP .Lno_overlap; 52 R3 = R1 + R2; 53 CC = R0 <= R3 (IU); /* (From+len) >= To */ 54 IF CC JUMP .Loverlap; 55.Lno_overlap: 56 R3 = 11; 57 CC = R2 <= R3; 58 IF CC JUMP .Lbytes; 59 R3 = R1 | R0; /* OR addresses together */ 60 R3 <<= 30; /* check bottom two bits */ 61 CC = AZ; /* AZ set if zero.*/ 62 IF !CC JUMP .Lbytes; /* Jump if addrs not aligned.*/ 63 64 I0 = P3; 65 P1 = P2 >> 2; /* count = n/4 */ 66 P1 += -1; 67 R3 = 3; 68 R2 = R2 & R3; /* remainder */ 69 P2 = R2; /* set remainder */ 70 R1 = [I0++]; 71 72 LSETUP (.Lquad_loops, .Lquad_loope) LC0=P1; 73#if ANOMALY_05000202 74.Lquad_loops: 75 [P0++] = R1; 76.Lquad_loope: 77 R1 = [I0++]; 78#else 79.Lquad_loops: 80.Lquad_loope: 81 MNOP || [P0++] = R1 || R1 = [I0++]; 82#endif 83 [P0++] = R1; 84 85 CC = P2 == 0; /* any remaining bytes? */ 86 P3 = I0; /* Ammend P3 to updated ptr. */ 87 IF !CC JUMP .Lbytes; 88 P3 = I1; 89 RTS; 90 91.Lbytes: LSETUP (.Lbyte2_s, .Lbyte2_e) LC0=P2; 92.Lbyte2_s: R1 = B[P3++](Z); 93.Lbyte2_e: B[P0++] = R1; 94 95.Lfinished: P3 = I1; 96 RTS; 97 98.Loverlap: 99 P2 += -1; 100 P0 = P0 + P2; 101 P3 = P3 + P2; 102 R1 = B[P3--] (Z); 103 CC = P2 == 0; 104 IF CC JUMP .Lno_loop; 105#if ANOMALY_05000245 106 NOP; 107 NOP; 108#endif 109 LSETUP (.Lol_s, .Lol_e) LC0 = P2; 110.Lol_s: B[P0--] = R1; 111.Lol_e: R1 = B[P3--] (Z); 112.Lno_loop: B[P0] = R1; 113 P3 = I1; 114 RTS; 115 116ENDPROC(_memmove) 117