rt.s

# BEGIN RT
.syntax unified

.section  .note.GNU-stack, "", %progbits

.data
.L_RT_print_int:
    .asciz "%d"
.L_RT_print_char:
    .asciz "%c"
.L_RT_print_true:
    .asciz "true"
.L_RT_print_false:
    .asciz "false"
.L_RT_print_ptr:
    .asciz "%p"
.L_RT_print_string:
    .asciz "%.*s"
.L_RT_rt_error:
    .asciz "#runtime_error#"

.text
rt_print_int:
    ldr r0, =.L_RT_print_int
    b printf
rt_print_char:
    ldr r0, =.L_RT_print_char
    b printf
rt_print_ptr:
    ldr r0, =.L_RT_print_ptr
    b printf
rt_print_bool:
    # Bool in in r1
    ldr r2, =.L_RT_print_true
    ldr r0, =.L_RT_print_false
    cmp r1, #0
    movne r0, r2
    b printf
rt_println:
    mov r0, #10
    b putchar
rt_print_string:
    mov r2, r1
    ldr r1, [r2, #-4]
    ldr r0, =.L_RT_print_string
    b printf

# https://godbolt.org/z/3q9cfox17
rt_error:
        ldr     r0, .LCPI0_0
.LPC0_0:
        add     r0, pc, r0
        bl      printf
        mov     r0, #255
        bl      exit
.LCPI0_0:
        .long   .L.str-(.LPC0_0+8)
rt_error_div0:
        ldr     r0, .LCPI1_0
.LPC1_0:
        add     r0, pc, r0
        bl      puts
        mov     r0, #255
        bl      exit
.LCPI1_0:
        .long   .Lstr-(.LPC1_0+8)
rt_error_sigsegv:
        ldr     r0, .LCPI2_0
.LPC2_0:
        add     r0, pc, r0
        bl      puts
        mov     r0, #255
        bl      exit
.LCPI2_0:
        .long   .Lstr.5-(.LPC2_0+8)
rt_array_new_word:
        push    {r4, r5, r11, lr}
        mov     r4, r0
        mov     r0, #4
        mov     r5, r1
        add     r0, r0, r4, lsl #2
        bl      malloc
        mov     r1, r0
        sub     r2, r5, #4
        str     r4, [r1], #4
.LBB3_1:                                @ =>This Inner Loop Header: Depth=1
        cmp     r4, #0
        beq     .LBB3_3
        ldr     r3, [r2, r4, lsl #2]
        sub     r4, r4, #1
        str     r3, [r1], #4
        b       .LBB3_1
.LBB3_3:
        add     r0, r0, #4
        pop     {r4, r5, r11, lr}
        mov     pc, lr
rt_array_new_byte:
        push    {r4, r5, r11, lr}
        mov     r4, r0
        add     r0, r0, #4
        mov     r5, r1
        bl      malloc
        str     r4, [r0], #4
        sub     r1, r5, #4
        mov     r2, r0
.LBB4_1:                                @ =>This Inner Loop Header: Depth=1
        cmp     r4, #0
        popeq   {r4, r5, r11, lr}
        moveq   pc, lr
        ldr     r3, [r1, r4, lsl #2]
        sub     r4, r4, #1
        strb    r3, [r2], #1
        b       .LBB4_1
rt_read_char:
        push    {r2, r3, r4, lr}
        cmp     r0, #4
        bls     .LBB5_2
        mov     r4, r0
        ldr     r0, .LCPI5_0
        add     r1, sp, #7
.LPC5_0:
        add     r0, pc, r0
        bl      __isoc99_scanf
        cmp     r0, #1
        ldrbeq  r0, [sp, #7]
        strbeq  r0, [r4]
        pop     {r2, r3, r4, lr}
        mov     pc, lr
.LBB5_2:
        bl      rt_error
.LCPI5_0:
        .long   .L.str.3-(.LPC5_0+8)
rt_read_int:
        push    {r2, r3, r4, lr}
        cmp     r0, #4
        bls     .LBB6_2
        mov     r4, r0
        ldr     r0, .LCPI6_0
        add     r1, sp, #4
.LPC6_0:
        add     r0, pc, r0
        bl      __isoc99_scanf
        cmp     r0, #1
        ldreq   r0, [sp, #4]
        streq   r0, [r4]
        pop     {r2, r3, r4, lr}
        mov     pc, lr
.LBB6_2:
        bl      rt_error
.LCPI6_0:
        .long   .L.str.4-(.LPC6_0+8)
rt_pair_new:
        push    {r4, r5, r11, lr}
        mov     r5, r0
        mov     r0, #8
        mov     r4, r1
        bl      malloc
        stm     r0, {r4, r5}
        pop     {r4, r5, r11, lr}
        mov     pc, lr
rt_init:
        ldr     r1, .LCPI8_0
        mov     r0, #11
.LPC8_0:
        add     r1, pc, r1
        b       signal
.LCPI8_0:
        .long   rt_error_sigsegv-(.LPC8_0+8)
rt_get_array_word:
        cmp     r0, #0
        bmi     .LBB9_2
        ldr     r2, [r1, #-4]
        cmp     r2, r0
        ldrgt   r0, [r1, r0, lsl #2]
        movgt   pc, lr
.LBB9_2:
        bl      rt_error
rt_get_array_byte:
        cmp     r0, #0
        bmi     .LBB10_2
        ldr     r2, [r1, #-4]
        cmp     r2, r0
        ldrbgt  r0, [r1, r0]
        movgt   pc, lr
.LBB10_2:
        bl      rt_error
.data
.L.str:
        .asciz  "#runtime_error#"

.L.str.3:
        .asciz  " %c"

.L.str.4:
        .asciz  "%d"

.Lstr:
        .asciz  "fatal error: division by zero"

.Lstr.5:
        .asciz  "fatal error: null pointer dereference"
.global main
.text
# END RT