139 lines
2.9 KiB
NASM
139 lines
2.9 KiB
NASM
# 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 add
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add:
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# Entering a new scope.
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# Symbols in symbol table:
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# println
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# x
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# i
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# y
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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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# Get x's offset from $sp from the symbol table and initialize x'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 x.
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lw $t0 0($t1)
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# Get y's offset from $sp from the symbol table and initialize y'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 y.
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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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jr $ra
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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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# Calling function add
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# Save $ra to a register
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move $t0 $ra
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# Save $t0-9 registers
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sw $t0 -12($sp)
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# Evaluate parameters and save to stack
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li $t1 3
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sw $t1 -16($sp)
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li $t1 4
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sw $t1 -20($sp)
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# Update the stack pointer
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add $sp $sp -12
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# Call the function
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jal add
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# Restore the stack pointer
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add $sp $sp 12
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# Restore $t0-9 registers
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lw $t0 -12($sp)
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# Restore $ra
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move $ra $t0
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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 5
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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 2
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# complete assignment statement with store
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sw $t1 0($t0)
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# Calling function add
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# Save $ra to a register
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move $t0 $ra
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# Save $t0-9 registers
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sw $t0 -12($sp)
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# Evaluate parameters and save to stack
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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 $t2 -4
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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 a.
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lw $t1 0($t2)
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sw $t1 -16($sp)
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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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sw $t1 -20($sp)
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# Update the stack pointer
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add $sp $sp -12
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# Call the function
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jal add
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# Restore the stack pointer
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add $sp $sp 12
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# Restore $t0-9 registers
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lw $t0 -12($sp)
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# Restore $ra
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move $ra $t0
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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 7 7"
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