74 lines
1.6 KiB
NASM
74 lines
1.6 KiB
NASM
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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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# Declare main as a global function
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.globl main
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j main
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# code for main
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main:
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# Entering a new scope.
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# Symbols in symbol table:
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# a
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# println
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# b
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# return
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# Update the stack pointer.
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addi $sp $sp -0
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# println
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la $a0 datalabel0
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li $v0 4
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syscall
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la $a0 newline
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li $v0 4
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syscall
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# Get a's offset from $sp from the symbol table and initialize a's address with it. We'll add $sp later.
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li $t0 -4
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# Add the stack pointer address to the offset.
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add $t0 $t0 $sp
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# Compute rhs for assignment =
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li $t1 3
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# complete assignment statement with store
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sw $t1 0($t0)
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# Get b's offset from $sp from the symbol table and initialize b's address with it. We'll add $sp later.
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li $t0 -8
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# Add the stack pointer address to the offset.
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add $t0 $t0 $sp
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# Compute rhs for assignment =
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li $t1 4
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# complete assignment statement with store
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sw $t1 0($t0)
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# println
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# Get a's offset from $sp from the symbol table and initialize a's address with it. We'll add $sp later.
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li $t1 -4
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# Add the stack pointer address to the offset.
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add $t1 $t1 $sp
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# Load the value of a.
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lw $t0 0($t1)
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# Get b's offset from $sp from the symbol table and initialize b's address with it. We'll add $sp later.
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li $t2 -8
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# Add the stack pointer address to the offset.
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add $t2 $t2 $sp
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# Load the value of b.
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lw $t1 0($t2)
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add $t0 $t0 $t1
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move $a0 $t0
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li $v0 1
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syscall
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la $a0 newline
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li $v0 4
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syscall
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# Exiting scope.
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addi $sp $sp 0
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li $v0 10
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syscall
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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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newline: .asciiz "\n"
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datalabel0: .asciiz "This program prints the number 7"
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