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@arian
Created February 27, 2013 16:35
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Selection Sort in MIPS assembly, for, I don't know, your PSP?
.text
j main # Jump to main-routine
.data
str1: .asciiz "Insert the array size \n"
str2: .asciiz "Insert the array elements,one per line \n"
str3: .asciiz "The sorted array is : \n"
str5: .asciiz "\n"
.text
.globl main
main:
la $a0, str1 # Print of str1
li $v0, 4 #
syscall #
li $v0, 5 # Get the array size(n) and
syscall # and put it in $v0
move $s2, $v0 # $s2=n
sll $s0, $v0, 2 # $s0=n*4
sub $sp, $sp, $s0 # This instruction creates a stack
# frame large enough to contain
# the array
la $a0, str2 #
li $v0, 4 # Print of str2
syscall #
move $s1, $zero # i=0
for_get: bge $s1, $s2, exit_get # if i>=n go to exit_for_get
sll $t0, $s1, 2 # $t0=i*4
add $t1, $t0, $sp # $t1=$sp+i*4
li $v0, 5 # Get one element of the array
syscall #
sw $v0, 0($t1) # The element is stored
# at the address $t1
la $a0, str5
li $v0, 4
syscall
addi $s1, $s1, 1 # i=i+1
j for_get
exit_get: move $a0, $sp # $a0=base address af the array
move $a1, $s2 # $a1=size of the array
jal isort # isort(a,n)
# In this moment the array has been
# sorted and is in the stack frame
la $a0, str3 # Print of str3
li $v0, 4
syscall
move $s1, $zero # i=0
for_print: bge $s1, $s2, exit_print # if i>=n go to exit_print
sll $t0, $s1, 2 # $t0=i*4
add $t1, $sp, $t0 # $t1=address of a[i]
lw $a0, 0($t1) #
li $v0, 1 # print of the element a[i]
syscall #
la $a0, str5
li $v0, 4
syscall
addi $s1, $s1, 1 # i=i+1
j for_print
exit_print: add $sp, $sp, $s0 # elimination of the stack frame
li $v0, 10 # EXIT
syscall #
# selection_sort
isort: addi $sp, $sp, -20 # save values on stack
sw $ra, 0($sp)
sw $s0, 4($sp)
sw $s1, 8($sp)
sw $s2, 12($sp)
sw $s3, 16($sp)
move $s0, $a0 # base address of the array
move $s1, $zero # i=0
subi $s2, $a1, 1 # lenght -1
isort_for: bge $s1, $s2, isort_exit # if i >= length-1 -> exit loop
move $a0, $s0 # base address
move $a1, $s1 # i
move $a2, $s2 # length - 1
jal mini
move $s3, $v0 # return value of mini
move $a0, $s0 # array
move $a1, $s1 # i
move $a2, $s3 # mini
jal swap
addi $s1, $s1, 1 # i += 1
j isort_for # go back to the beginning of the loop
isort_exit: lw $ra, 0($sp) # restore values from stack
lw $s0, 4($sp)
lw $s1, 8($sp)
lw $s2, 12($sp)
lw $s3, 16($sp)
addi $sp, $sp, 20 # restore stack pointer
jr $ra # return
# index_minimum routine
mini: move $t0, $a0 # base of the array
move $t1, $a1 # mini = first = i
move $t2, $a2 # last
sll $t3, $t1, 2 # first * 4
add $t3, $t3, $t0 # index = base array + first * 4
lw $t4, 0($t3) # min = v[first]
addi $t5, $t1, 1 # i = 0
mini_for: bgt $t5, $t2, mini_end # go to min_end
sll $t6, $t5, 2 # i * 4
add $t6, $t6, $t0 # index = base array + i * 4
lw $t7, 0($t6) # v[index]
bge $t7, $t4, mini_if_exit # skip the if when v[i] >= min
move $t1, $t5 # mini = i
move $t4, $t7 # min = v[i]
mini_if_exit: addi $t5, $t5, 1 # i += 1
j mini_for
mini_end: move $v0, $t1 # return mini
jr $ra
# swap routine
swap: sll $t1, $a1, 2 # i * 4
add $t1, $a0, $t1 # v + i * 4
sll $t2, $a2, 2 # j * 4
add $t2, $a0, $t2 # v + j * 4
lw $t0, 0($t1) # v[i]
lw $t3, 0($t2) # v[j]
sw $t3, 0($t1) # v[i] = v[j]
sw $t0, 0($t2) # v[j] = $t0
jr $ra
@NewUser2222
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how can I sort with floating point ???

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