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Diffstat (limited to 'arch/blackfin/lib/memmove.S')
| -rw-r--r-- | arch/blackfin/lib/memmove.S | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/arch/blackfin/lib/memmove.S b/arch/blackfin/lib/memmove.S new file mode 100644 index 0000000000..e385c4f6f5 --- /dev/null +++ b/arch/blackfin/lib/memmove.S @@ -0,0 +1,96 @@ +/* + * File: memmove.S + * + * Copyright 2004-2007 Analog Devices Inc. + * Enter bugs at http://blackfin.uclinux.org/ + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see the file COPYING, or write + * to the Free Software Foundation, Inc., + * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +.align 2 + +/* + * C Library function MEMMOVE + * R0 = To Address (leave unchanged to form result) + * R1 = From Address + * R2 = count + * Data may overlap + */ + +.globl _memmove; +.type _memmove, STT_FUNC; +_memmove: + I1 = P3; + P0 = R0; /* P0 = To address */ + P3 = R1; /* P3 = From Address */ + P2 = R2 ; /* P2 = count */ + CC = P2 == 0; /* Check zero count*/ + IF CC JUMP .Lfinished; /* very unlikely */ + + CC = R1 < R0 (IU); /* From < To */ + IF !CC JUMP .Lno_overlap; + R3 = R1 + R2; + CC = R0 <= R3 (IU); /* (From+len) >= To */ + IF CC JUMP .Loverlap; +.Lno_overlap: + R3 = 11; + CC = R2 <= R3; + IF CC JUMP .Lbytes; + R3 = R1 | R0; /* OR addresses together */ + R3 <<= 30; /* check bottom two bits */ + CC = AZ; /* AZ set if zero.*/ + IF !CC JUMP .Lbytes ; /* Jump if addrs not aligned.*/ + + I0 = P3; + P1 = P2 >> 2; /* count = n/4 */ + P1 += -1; + R3 = 3; + R2 = R2 & R3; /* remainder */ + P2 = R2; /* set remainder */ + R1 = [I0++]; + + LSETUP (.Lquad_loop , .Lquad_loop) LC0=P1; +.Lquad_loop: MNOP || [P0++] = R1 || R1 = [I0++]; + [P0++] = R1; + + CC = P2 == 0; /* any remaining bytes? */ + P3 = I0; /* Ammend P3 to updated ptr. */ + IF !CC JUMP .Lbytes; + P3 = I1; + RTS; + +.Lbytes: LSETUP (.Lbyte2_s , .Lbyte2_e) LC0=P2; +.Lbyte2_s: R1 = B[P3++](Z); +.Lbyte2_e: B[P0++] = R1; + +.Lfinished: P3 = I1; + RTS; + +.Loverlap: + P2 += -1; + P0 = P0 + P2; + P3 = P3 + P2; + R1 = B[P3--] (Z); + CC = P2 == 0; + IF CC JUMP .Lno_loop; + LSETUP (.Lol_s, .Lol_e) LC0 = P2; +.Lol_s: B[P0--] = R1; +.Lol_e: R1 = B[P3--] (Z); +.Lno_loop: B[P0] = R1; + P3 = I1; + RTS; + +.size _memmove, .-_memmove |