RIOT/cpu/lpc23xx/asmfunc.s

/*
 * Copyright (C) 2014 Freie Universität Berlin
 *
 * This file is subject to the terms and conditions of the GNU Lesser
 * General Public License v2.1. See the file LICENSE in the top level
 * directory for more details.
 */

/*
@-----------------------------------------------------------@
@ Fast Block Copy (declared in diskio.h)
@-----------------------------------------------------------@
*/

.global copy_un2al
.arm
copy_un2al:
    STMFD   SP!, {R4-R8}
    ANDS    IP, R1, #3
    BEQ lb_align

    BIC R1, #3
    MOV IP, IP, LSL #3
    RSB R8, IP, #32
    LDMIA   R1!, {R7}
lb_l1:  MOV R3, R7
    LDMIA   R1!, {R4-R7}
    MOV R3, R3, LSR IP
    ORR R3, R3, R4, LSL R8
    MOV R4, R4, LSR IP
    ORR R4, R4, R5, LSL R8
    MOV R5, R5, LSR IP
    ORR R5, R5, R6, LSL R8
    MOV R6, R6, LSR IP
    ORR R6, R6, R7, LSL R8
    SUBS    R2, R2, #16
    STMIA   R0!, {R3-R6}
    BNE lb_l1
    LDMFD   SP!, {R4-R8}
    BX  LR

lb_align:
    LDMIA   R1!, {R3-R6}
    SUBS    R2, R2, #16
    STMIA   R0!, {R3-R6}
    BNE lb_align
    LDMFD   SP!, {R4-R8}
    BX  LR


.global copy_al2un
.arm
copy_al2un:
    STMFD   SP!, {R4-R8}
    ANDS    IP, R0, #3
    BEQ sb_align

    MOV IP, IP, LSL #3
    RSB R8, IP, #32

    LDMIA   R1!, {R4-R7}
sb_p1:  STRB    R4, [R0], #1
    MOV R4, R4, LSR #8
    TST R0, #3
    BNE sb_p1
    ORR R4, R4, R5, LSL IP
    MOV R5, R5, LSR R8
    ORR R5, R5, R6, LSL IP
    MOV R6, R6, LSR R8
    ORR R6, R6, R7, LSL IP
    SUBS    R2, R2, #16
    STMIA   R0!, {R4-R6}

sb_l1:  MOV R3, R7
    LDMIA   R1!, {R4-R7}
    MOV R3, R3, LSR R8
    ORR R3, R3, R4, LSL IP
    MOV R4, R4, LSR R8
    ORR R4, R4, R5, LSL IP
    MOV R5, R5, LSR R8
    ORR R5, R5, R6, LSL IP
    MOV R6, R6, LSR R8
    ORR R6, R6, R7, LSL IP
    SUBS    R2, R2, #16
    STMIA   R0!, {R3-R6}
    BNE sb_l1

    MOV R7, R7, LSR R8
sb_p2:  SUBS    IP, IP, #8
    STRB    R7, [R0], #1
    MOV R7, R7, LSR #8
    BNE sb_p2

    LDMFD   SP!, {R4-R8}
    BX  LR

sb_align:
    LDMIA   R1!, {R3-R6}
    SUBS    R2, #16
    STMIA   R0!, {R3-R6}
    BNE sb_align
    LDMFD   SP!, {R4-R8}
    BX  LR

.end