bootasm/assembler_2.asm at main · fox32-arch/bootasm · GitHub

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; continues from assembler_1.asm
assembler_2:
    call r19
    movz.8 r0, 10
    call r18

    ret

; inputs:
; r3: source or target string arg pointer
write_source_target:
    mov r10, r0
    movz.8 r11, [current_size]
    cmp r3, 0
    ifz ret
    movz.8 r1, 16
    cmp.8 [r3], 'r'
    ifz movz.8 r11, 0
    ifz movz.8 r1, 10
    ifz inc r3
    cmp.8 [r3], '['
    ifnz rjmp.8 write_source_target_cont
    movz.8 r11, 2 ; immediate pointers are always 32 bits long
    inc r3
    cmp.8 [r3], 'r' ; "[r", r3 incremented once above
    ifz movz.8 r11, 0
    ifz movz.8 r1, 10
    ifz inc r3 ; already incremented once above
write_source_target_cont:
    mov r0, r3
    call [ROM_string_to_int]
    cmp.8 r11, 0
    ifz rjmp.16 write_source_target_byte
    cmp.8 r11, 1
    ifz rjmp.16 write_source_target_half
    cmp.8 r11, 2
    ifz rjmp.16 write_source_target_word
write_source_target_end:
    mov r0, r10
    ret
write_source_target_byte:
    mov.8 [r10], r0
    call r16
    call r17
    inc r10
    rjmp.16 write_source_target_end
write_source_target_half:
    mov.16 [r10], r0
    mov r31, 2
write_source_target_half_loop:
    call r16
    call r17
    sra r0, 8
    rloop.8 write_source_target_half_loop
    inc r10, 2
    rjmp.16 write_source_target_end
write_source_target_word:
    mov [r10], r0
    mov r31, 4
write_source_target_word_loop:
    call r16
    call r17
    sra r0, 8
    rloop.8 write_source_target_word_loop
    inc r10, 4
    rjmp.16 write_source_target_end

print_space:
    push r0
    movz.8 r0, ' '
    call r18
    pop r0
    ret