I need to translate some MIPS assembly instructions to C code. I think I got it, but it seems counter-intuitive. Any help? We have variables f, g, h, i, j stored in registers $s0, $s1, $s2, $s3 and $s4 respectively. The base of arrays A and B are stored in $s6 and $s7 respectively. 4 byte words. Comments in the code are my own.
addi $t0, $s6, 4 # $t0 = A[1]
add $t1, $s6, $0 # $t1 = A[0]
sw $t1, 0($t0) # $t0 = A[0]
lw $t0, 0($t0) # $t0 = A[0]
add $s0, $t1, $t0 # f = A[0] + A[0]
I just feel like I'm wrong. Why make $t0 A[1] first if we never use it?
I think you have got in completely wrong.
addi $t0, $s6, 4 # $t0 = A[1]
After the addi, register $t0
became the memory address of A[1], which would be &A[1]
, not A[1]
. To get value of A[1], you need to use lw
after you done the addi
lw $t0, 0($t0) # $t0 =A[1]
sw $t1, 0($t0) # $t0 = A[0]
You've got this back-to-front. It is a store, so it is used:
sw $t1, 0($t0) # A[1] = $t1
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With