CHAPTER 14. LOOPS CHAPTER 14. LOOPS

stp x29, x30, [sp, -32]!
; set up stack frame:
add x29, sp, 0
; save contents of X19 register in the local stack:
str x19, [sp,16]
; we will use W19 register as counter.
; set initial value of 2 to it:
mov w19, 2
.L3:
; prepare first argument of printing_function():
mov w0, w19
; increment counter register.
add w19, w19, 1
; W0 here still holds value of counter value before increment.
bl printing_function
; is it end?
cmp w19, 10
; no, jump to the loop body begin:
bne .L3
; return 0
mov w0, 0
; restore contents of X19 register:
ldr x19, [sp,16]
; restore FP and LR values:
ldp x29, x30, [sp], 32
ret
.LC0:
.string "f(%d)\n"

14.1.5 MIPS.

Listing 14.9: Non-optimizing GCC 4.4.5 (IDA)

main:

; IDA is not aware of variable names in local stack
; We gave them names manually:
i = -0x10
saved_FP = -8
saved_RA = -4

; function prologue:
addiu $sp, -0x28
sw $ra, 0x28+saved_RA($sp)
sw $fp, 0x28+saved_FP($sp)
move $fp, $sp
; initialize counter at 2 and store this value in local stack
li $v0, 2
sw $v0, 0x28+i($fp)
; pseudoinstruction. "BEQ $ZERO, $ZERO, loc_9C" there in fact:
b loc_9C
or $at, $zero ; branch delay slot, NOP

---------------------------------------------------------------------------

loc_80: # CODE XREF: main+48
; load counter value from local stack and call printing_function():
lw $a0, 0x28+i($fp)
jal printing_function
or $at, $zero ; branch delay slot, NOP
; load counter, increment it, store it back:
lw $v0, 0x28+i($fp)
or $at, $zero ; NOP
addiu $v0, 1
sw $v0, 0x28+i($fp)

loc_9C: # CODE XREF: main+18
; check counter, is it 10?
lw $v0, 0x28+i($fp)