```py

# Celsius to fahrenheit


.data

msg: .asciiz "Enter celsius : "

const9: .float 9.0

const5: .float 5.0

const32: .float 32.0

zeroF: .float 0.0



.text

.globl main

main: # Expand stack and save $ra

addi $sp, $sp, -4

sw $ra, ($sp)

li $v0, 4 # print_str syscall number

la $a0, msg # arg0 : msg

syscall

li $v0, 6 # read_float syscall number

syscall # $f0 - user input float number

jal c2f

li $v0, 2 # print_float syscall number

lwc1 $f4, zeroF # $f4 = 0.0

add.s $f12, $f0, $f4 # move $f0 to $f12. $f12 is arg.

syscall

# Shrink stack and load $ra

lw $ra, ($sp)

addi $sp, $sp, 4

jr $ra

c2f: lwc1 $f16, const5 # $f16 = 5.0 (ldc1, load double coprocess1)

lwc1 $f18, const9 # $f18 = 9.0

div.s $f18, $f18, $f16 # $f18 = 9.0 / 5.0

mul.s $f0, $f0, $f18 # $f0 = $f0 * 9/5

lwc1 $f16, const32

add.s $f0, $f0, $f16 # $f0 = $f0 + 32

jr $ra

```


실수를 계산하는 coprocessor 레지스터(`` $f0, $f1, ...``)와 정수 레지스터간 데이터 교환

```py

mtc1 $t0, $f0    #move to coprocess1

mfc1 $t0, $f0    #move from coprocess1

```


실수↔정수 형변환

```py

cvt.s.w $f0, $f0    # Convert to Single from Integer

cvt.w.s $f0, $f0    # Convert to Integer from Single

```



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