| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | /* memmove.S |
| 2 | * Copyright (C) 2003-2007 Analog Devices Inc., All Rights Reserved. |
| 3 | * |
| 4 | * This file is subject to the terms and conditions of the GNU Library General |
| 5 | * Public License. See the file "COPYING.LIB" in the main directory of this |
| 6 | * archive for more details. |
| 7 | * |
| 8 | * Non-LGPL License also available as part of VisualDSP++ |
| 9 | * http://www.analog.com/processors/resources/crosscore/visualDspDevSoftware.html |
| 10 | */ |
| 11 | |
| 12 | #include <sysdep.h> |
| 13 | |
| 14 | /* void *memmove(void *dest, const void *src, size_t n); |
| 15 | * R0 = To Address (dest) (leave unchanged to form result) |
| 16 | * R1 = From Address (src) |
| 17 | * R2 = count (n) |
| 18 | * |
| 19 | * Note: Data may overlap |
| 20 | */ |
| 21 | |
| 22 | .text |
| 23 | |
| 24 | .align 2 |
| 25 | |
| 26 | .weak _memmove |
| 27 | ENTRY(_memmove) |
| 28 | I1 = P3; |
| 29 | P0 = R0; /* P0 = To address */ |
| 30 | P3 = R1; /* P3 = From Address */ |
| 31 | P2 = R2; /* P2 = count */ |
| 32 | CC = P2 == 0; /* Check zero count*/ |
| 33 | IF CC JUMP .Lfinished; /* very unlikely */ |
| 34 | |
| 35 | CC = R1 < R0 (IU); /* From < To */ |
| 36 | IF !CC JUMP .Lno_overlap; |
| 37 | R3 = R1 + R2; |
| 38 | CC = R0 <= R3 (IU); /* (From+len) >= To */ |
| 39 | IF CC JUMP .Loverlap; |
| 40 | .Lno_overlap: |
| 41 | R3 = 11; |
| 42 | CC = R2 <= R3; |
| 43 | IF CC JUMP .Lbytes; |
| 44 | R3 = R1 | R0; /* OR addresses together */ |
| 45 | R3 <<= 30; /* check bottom two bits */ |
| 46 | CC = AZ; /* AZ set if zero.*/ |
| 47 | IF !CC JUMP .Lbytes; /* Jump if addrs not aligned.*/ |
| 48 | |
| 49 | I0 = P3; |
| 50 | P1 = P2 >> 2; /* count = n/4 */ |
| 51 | P1 += -1; |
| 52 | R3 = 3; |
| 53 | R2 = R2 & R3; /* remainder */ |
| 54 | P2 = R2; /* set remainder */ |
| 55 | R1 = [I0++]; |
| 56 | |
| 57 | #if !defined(__WORKAROUND_AVOID_DAG1) |
| 58 | LSETUP (.Lquad_loop, .Lquad_loop) LC0=P1; |
| 59 | .Lquad_loop: MNOP || [P0++] = R1 || R1 = [I0++]; |
| 60 | #else |
| 61 | LSETUP (.Lquad_loop_s, .Lquad_loop_e) LC0=P1; |
| 62 | .Lquad_loop_s: [P0++] = R1; |
| 63 | .Lquad_loop_e: R1 = [I0++]; |
| 64 | #endif |
| 65 | [P0++] = R1; |
| 66 | |
| 67 | CC = P2 == 0; /* any remaining bytes? */ |
| 68 | P3 = I0; /* Ammend P3 to updated ptr. */ |
| 69 | IF !CC JUMP .Lbytes; |
| 70 | P3 = I1; |
| 71 | RTS; |
| 72 | |
| 73 | .Lbytes: LSETUP (.Lbyte2_s, .Lbyte2_e) LC0=P2; |
| 74 | .Lbyte2_s: R1 = B[P3++](Z); |
| 75 | .Lbyte2_e: B[P0++] = R1; |
| 76 | |
| 77 | .Lfinished: P3 = I1; |
| 78 | RTS; |
| 79 | |
| 80 | .Loverlap: |
| 81 | P2 += -1; |
| 82 | P0 = P0 + P2; |
| 83 | P3 = P3 + P2; |
| 84 | R1 = B[P3--] (Z); |
| 85 | CC = P2 == 0; |
| 86 | IF CC JUMP .Lno_loop; |
| 87 | #if defined(__WORKAROUND_SPECULATIVE_LOADS) |
| 88 | NOP; |
| 89 | NOP; |
| 90 | #endif |
| 91 | LSETUP (.Lol_s, .Lol_e) LC0 = P2; |
| 92 | .Lol_s: B[P0--] = R1; |
| 93 | .Lol_e: R1 = B[P3--] (Z); |
| 94 | .Lno_loop: B[P0] = R1; |
| 95 | P3 = I1; |
| 96 | RTS; |
| 97 | |
| 98 | .size _memmove,.-_memmove |
| 99 | |
| 100 | libc_hidden_def (memmove) |