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41 lines
1.1 KiB
41 lines
1.1 KiB
5 years ago
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# A demonstration of some simple MIPS instructions
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# used to test QtSPIM
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# Declare main as a global function
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.globl main
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# All program code is placed after the
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# .text assembler directive
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.text
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# The label 'main' represents the starting point
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main:
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li $t2, 25 # Load immediate value (25)
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lw $t3, value # Load the word stored in value (see bottom)
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add $t4, $t2, $t3 # Add
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sll $t1, $s3, 2 # sll
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BEQ $t1, $t2, loop
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add $s0,$a1, $t7
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loop:
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sub $t5, $t2, $t3 # Subtract
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sw $t5, Z #Store the answer in Z (declared at the bottom)
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# Exit the program by means of a syscall.
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# There are many syscalls - pick the desired one
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# by placing its code in $v0. The code for exit is "10"
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li $v0, 10 # Sets $v0 to "10" to select exit syscall
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syscall # Exit
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# All memory structures are placed after the
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# .data assembler directive
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.data
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# The .word assembler directive reserves space
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# in memory for a single 4-byte word (or multiple 4-byte words)
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# and assigns that memory location an initial value
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# (or a comma separated list of initial values)
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value: .word 12
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Z: .word 0
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