Class: MipsDisassembler

Inherits:
Object
  • Object
show all
Defined in:
mips_disassembler.rb

Overview

This class disassembles instructions from hex or binary to human readable Mips Initialization:

MipsDisassember.new(array_of_instructions, starting_address, is_hex)

Definition of parameters:

array_of_instructions: an array of instructions in hex or binary.
                       Will generally be strings.
starting_address: whatever address you want the instructions to start at
is_hex: true or false, depending on whether or not the instructions are hex or not
        true if hex, false if binary

Example:

> array_of_hex = ["0x022DA822",
                  "0x8EF30018",
                  "0x12A70004",
                  "0x02689820",
                  "0xAD930018",
                  "0x02697824",
                  "0xAD8FFFF4",
                  "0x018C6020",
                  "0x02A4A825",
                  "0x158FFFF6",
                  "0x8E59FFF0"]

> mips = MipsDisassembler.new(array_of_hex, "7A060", true)
> results = mips.disassemble
> results.each { |instruction| puts instruction }

Output:

7A060 sub $21 $17 $13
7a064 lw $19, 24 ($23)
7a068 beq $7, $21, address 0x7a07c
7a06c add $19 $19 $8
7a070 sw $19, 24 ($12)
7a074 and $15 $19 $9
7a078 sw $15, -12 ($12)
7a07c add $12 $12 $12
7a080 or $21 $21 $4
7a084 bne $15, $12, address 0xba060
7a088 lw $25, -16 ($18)

Author:

  • Jennifer Konikowski <jmkoni@icloud.com>

Instance Method Summary collapse

Constructor Details

#initialize(array_of_instructions, starting_address, is_hex) ⇒ MipsDisassembler

Note:

Each object in array_of_instructions should be a string representation of either binary or hexadecimal number

Creates a new instance of MipsDisassembler

Examples:

Create an object

mips = MipsDisassembler.new(["0x022DA822", "0x8EF30018", "0x12A70004"], "7A060", true)

Parameters:

  • array_of_instructions (Array) —

    the array of string instructions

  • starting_address (String) —

    starting address for instructions, should be a string hexadecimal value

  • is_hex (Boolean) —

    true if array of instructions is in hex, false if in binary



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# File 'mips_disassembler.rb', line 51

def initialize(array_of_instructions, starting_address, is_hex)
  @instructions = array_of_instructions
  @starting_address = starting_address
  @is_hex = is_hex
end

Instance Method Details

#disassemble ⇒ Array

Note:

Determines if r-format or i-format and parses accordingly.

Takes binary/hex instructions and starting address and return an array of MIPs instructions.

Examples:

Disassemble instructions

mips.disassemble => ["7A060 sub $21 $17 $13", "7a064 lw $19, 24 ($23)", "7a068 beq $7, $21, address 0x7a07c"]

Returns:

  • (Array) —

    an array of MIPs instructions, human-readable



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# File 'mips_disassembler.rb', line 62

def disassemble
  disassemble_instructions(@instructions, @starting_address, @is_hex)
end

#output_to_file ⇒ void

Note:

File “mips_results.txt” will be created in same directory as code

This method returns an undefined value.

write MIPs instructions to file



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# File 'mips_disassembler.rb', line 69

def output_to_file
  File.open("mips_results.txt", "w") do |f|
    in_file = ""
    disassemble.each { |instruction| in_file << instruction + "\n" }
    f.write(in_file)
  end
end