.data
$LowerBoundErr$$:
.asciiz "Runtime error: array index less than zero\n"

.data
$ChrErr$$:
.asciiz "Runtime error: Illegal ASCII code for chr\n"

.data
$SubStrErr$$:
.asciiz "Runtime error: Access to illegal location in substring\n"

$UpperBoundErr$$:
.asciiz "Runtime error: array index greater than array size\n"

.data
$NullErr$$:
.asciiz "Runtime error: attempt to access fields of a null record\n"

.data
$SizeErr$$:
.asciiz "Runtime error: only positive size array objects can be created\n"

.data
$NewLine$$:
.asciiz "\n"

.data
$Dummy$$:
.asciiz "Dummy string\n"

.text
.globl main
main:
jal $Main$$
li $v0, 10
syscall

.text
$NullExit$$:
la $a0, $NullErr$$
li $v0, 4
syscall
li $v0, 10
syscall

.text
$LowerBoundExit$$:
la $a0, $LowerBoundErr$$
li $v0, 4
syscall
li $v0, 10
syscall

.text
$UpperBoundExit$$:
la $a0, $UpperBoundErr$$
li $v0, 4
syscall
li $v0, 10
syscall

.text
$SizeError$$:
la $a0, $SizeErr$$
li $v0, 4
syscall
li $v0, 10
syscall

.text
$Malloc$$:
sw $fp,-4($sp)
la $fp,-4($sp)
la $sp,-4($fp)
sw $ra,-4($fp)
li $v0,9
syscall
la $sp,4($fp)
lw $ra,-4($fp)
lw $fp,($fp)
jr $ra

.text
$StringLength$$:
move $t4,$zero
move $t2,$a0
NEXTSL:
lbu $t3,($t2)
beq $t3,$zero,ENDLENGTH
addi $t2,$t2,1
addi $t4,$t4,1
j NEXTSL
ENDLENGTH:
move $v0,$t4
jr $ra

# 0 - equal
# 1 - left is greater
# 2 - right is greater

.text
$StringComp$$:
sw $fp,-12($sp)
la $fp,-4($sp)
la $sp,-16($fp)
sw $ra,-12($fp)
sw $a0,-4($fp)
sw $a1,($fp)
jal $StringLength$$
sw $v0,-16($fp)
lw $a0,($fp)
jal $StringLength$$
lw $t7,-16($fp)
lw $t8,-4($fp)
lw $t9,($fp)
blt $t7,$v0,COMPLOOP
move $t7,$v0
COMPLOOP:
beq $t7,$zero,EX1
lbu $t5,($t8)
lbu $t6,($t9)
bne $t5,$t6,EX2
sub $t7,$t7,1
addi $t8,$t8,1
addi $t9,$t9,1
j COMPLOOP
EX1:
lbu $t5,($t8)
bne $t5,$zero,LGT
lbu $t6,($t9)
beq $t6,$zero,EQ
li $v0,2
j EX
EQ:
li $v0,0
j EX
EX2:
blt $t5,$t6,LLT
LGT:
li $v0,1
j EX
LLT:
li $v0,2
EX:
la $sp,4($fp)
lw $ra,-12($fp)
lw $fp,-8($fp)
jr $ra

.text
$StringEqual$$:
sw $fp,-4($sp)
la $fp,-4($sp)
la $sp,-4($fp)
sw $ra,-4($fp)
jal $StringComp$$
beq $v0,$zero,EQ1
li $v0,0
j EQEX
EQ1:
li $v0,1
EQEX:
la $sp,4($fp)
lw $ra,-4($fp)
lw $fp,($fp)
jr $ra

.text
$StringLT$$:
sw $fp,-4($sp)
la $fp,-4($sp)
la $sp,-4($fp)
sw $ra,-4($fp)
jal $StringComp$$
li $t3,2
beq $v0,$t3,LT1
li $v0,0
j LTEX
LT1:
li $v0,1
LTEX:
la $sp,4($fp)
lw $ra,-4($fp)
lw $fp,($fp)
jr $ra

.text
$StringLEQ$$:
sw $fp,-4($sp)
la $fp,-4($sp)
la $sp,-4($fp)
sw $ra,-4($fp)
jal $StringComp$$
li $t3,2
beq $v0,$t3,LEQ1
beq $v0,$zero,LEQ1
li $v0,0
j LEQEX
LEQ1:
li $v0,1
LEQEX:
la $sp,4($fp)
lw $ra,-4($fp)
lw $fp,($fp)
jr $ra

.text
$InitArray$$:
sw $fp,-12($sp)
la $fp,-4($sp)
la $sp,-12($fp)
sw $a1,($fp)
sw $a0,-4($fp)
sw $ra,-12($fp)
add $a0,$a0,1
mul $a0,$a0,4
li $v0,9
syscall
lw $t0,-4($fp)
sw $t0,($v0)
move $t1,$v0
lw $t2,($fp)
$CALoop$$:
beqz $t0, $CAEnd$$
add $t1,$t1,4
sw $t2,($t1)
sub $t0,$t0,1
j $CALoop$$
$CAEnd$$:
la $sp,4($fp)
lw $ra,-12($fp)
lw $fp,-8($fp)
jr $ra

.text
$Print$$:
sw $fp,-4($sp)
la $fp,-4($sp)
la $sp,-4($fp)
sw $ra,-4($fp)
move $a0,$a1
li $v0,4
syscall
lw $ra,-4($fp)
la $sp,4($fp)
lw $fp,($fp)
jr $ra

# doesn't seem possible to do anything more with SPIM
.text 
$Flush$$:
jr $ra

.text
$GetChar$$:
sw $fp,-4($sp)
la $fp,-4($sp)
la $sp,-8($fp)
sw $ra,-4($fp)
li $a0,2
li $v0,9
syscall
sw $v0,-8($fp)
move $a0,$v0
li $a1,2
li $v0,8
syscall
lw $v0,-8($fp)
la $sp,4($fp)
lw $ra,-4($fp)
lw $fp,($fp)
jr $ra

.text
$Ord$$:
lbu $v0,($a1)
bne $v0,$zero,NL
li $v0,-1
NL:
jr $ra

.text
$Chr$$:
blt $a1,$zero,ERR
bgt $a1,255,ERR
sw $fp,-8($sp)
la $fp,-4($sp)
la $sp,-8($fp)
sw $ra,-8($fp)
sw $a1,($fp)
li $a0,4
li $v0,9
syscall
lw $t0,($fp)
sb $t0,($v0)
sb $zero,1($v0)
la $sp,4($fp)
lw $ra,-8($fp)
lw $fp,-4($fp)
jr $ra
ERR:
la $a0,$ChrErr$$
li $v0,4
syscall
li $v0,10
syscall

.text
$Exit$$:
li $v0,10
syscall

.text
$Not$$:
beq $a1,$zero,EQZERO
li $v0,0
jr $ra
EQZERO:
li $v0,1
jr $ra

.text
$SubString$$:
sw $fp,-16($sp)
la $fp,-4($sp)
la $sp,-16($fp)
sw $ra,-16($fp)
sw $a1,-8($fp)
sw $a2,-4($fp)
sw $a3,($fp)
blt $a2,$zero,SubErr
move $a0,$a1
jal $StringLength$$
lw $t1,-4($fp)
lw $t2,($fp)
add $t0,$t1,$t2
blt $v0,$t0,SubErr
addi $a0,$t2,1
li $v0,9
syscall
move $t0,$v0
lw $t1,-8($fp)
lw $t2,-4($fp)
lw $t3,($fp)
add $t1,$t1,$t2
SSLoop:
ble $t3,$zero,FinSub
lbu $t2,($t1)
sb $t2,($t0)
addi $t0,$t0,1
addi $t1,$t1,1
sub $t3,$t3,1
j SSLoop
FinSub:
sb $zero,($t0)
lw $ra,-16($fp)
la $sp,4($fp)
lw $fp,-12($fp)
jr $ra
SubErr:
la $a0,$SubStrErr$$
li $v0,4
syscall
li $v0,10
syscall

.text
$Concat$$:
sw $fp,-12($sp)
la $fp,-4($sp)
la $sp,-20($fp)
sw $ra,-12($fp)
sw $a2,($fp)
sw $a1,-4($fp)
move $a0,$a1
jal $StringLength$$
sw $v0,-16($fp)
lw $a0,($fp)
jal $StringLength$$
sw $v0,-20($fp)
lw $t0,-16($fp)
add $a0,$t0,$v0
addi $a0,$a0,1
li $v0,9
syscall
move $t0,$v0
lw $t1,-16($fp)
lw $t2,-4($fp)
lw $t3,-20($fp)
lw $t4,($fp)
CopyOne:
ble $t1,$zero,CopyTwo
lbu $t5,($t2)
sb $t5,($t0)
addi $t2,$t2,1
addi $t0,$t0,1
sub $t1,$t1,1
j CopyOne
CopyTwo:
ble $t3,$zero,FinCat
lbu $t5,($t4)
sb $t5,($t0)
addi $t4,$t4,1
addi $t0,$t0,1
sub $t3,$t3,1
j CopyTwo
FinCat:
sb $zero,($t0)
lw $ra,-12($fp)
la $sp,4($fp)
lw $fp,-8($fp)
jr $ra


.text
$Size$$:
sw $fp,-4($sp)
la $fp,-4($sp)
la $sp,-4($fp)
sw $ra,-4($fp)
move $a0,$a1
jal $StringLength$$
lw $ra,-4($fp)
la $sp,4($fp)
lw $fp($fp)
jr $ra

.data
.align 2
L1:
.asciiz " "

.data
.align 2
L0:
.asciiz " "

.data
.align 2
L13:
.asciiz "10 > 20
"

.data
.align 2
L14:
.asciiz "10 <= 20
"

.data
.align 2
L18:
.asciiz "a < b
"

.data
.align 2
L19:
.asciiz "a >= b
"

.text
$Main$$:
sw $fp,-8($sp)
la $fp,-4($sp)
la $sp,-16($fp)
L23:
sw $a0,0($fp)
sw $ra,-16($fp)
li $t0,12
sw $t0,-12($fp)
li $t0,19
sw $t0,-8($fp)
L16:
la $a1,L14
L17:
addi $t0,$fp,0
lw $a0,($t0)
jal $Print$$
lw $t0,-12($fp)
lw $t1,-8($fp)
blt $t0,$t1,L20
L21:
addi $t0,$fp,0
lw $a0,($t0)
la $a1,L19
jal $Print$$
L22:
lw $ra,-16($fp)
j L12
L15:
la $a1,L13
j L17
L20:
addi $t0,$fp,0
lw $a0,($t0)
la $a1,L18
jal $Print$$
j L22
L12:
la $sp,4($fp)
lw $fp,-8($sp)
jr $ra