bits 8

@define case_result %numb
@define test_cases %int
@define test_end %text
@define test_end_data '\n'
@define total_tests %uint
imm r1 1

out total_tests 4

// sp is rw
    mov r2 sp
    mov sp 69
    mov r1 sp
    mov sp r2
    sub r1 r1 69
    out case_result r1
out test_cases 1
out test_end test_end_data
imm r1 1

// sp affects stack pushes and pops
    psh 75
    psh 4
    psh 20
    inc sp sp
    psh 69

    pop r1
    sub r1 r1 69
    out case_result r1

    pop r1
    sub r1 r1 4
    out case_result r1

    pop r1
    sub r1 r1 75
    out case_result r1

    imm r1 1
    dec sp sp

    pop r1
    sub r1 r1 75
    out case_result r1
out test_cases 4
out test_end test_end_data
imm r1 1

// pc reg is readable
    .pc_read_first
    mov r1 pc
    bne .pc_read_fail r1 .pc_read_first

    out case_result 0
    jmp .pc_read_end

    .pc_read_fail
    out case_result 1
.pc_read_end
out test_cases 1
out test_end test_end_data
imm r1 1

// pc reg can be used to jump
    mov pc .pc_write_ok
    out case_result 1
    jmp .pc_write_end

    .pc_write_ok
    out case_result 0
.pc_write_end
out test_cases 1
out test_end test_end_data
imm r1 1