ARMed

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A basic ARM emulator written in Golang

Build instructions

Build from source

Requires Go to be installed and configured

go get github.com/coderick14/ARMed

Download the compiled binary

Just download the binary for your required OS and architecture from releases

Usage

ARMed --help will show all the usage details

ARMed version 1.0
Author : https://github.com/coderick14

ARMed is a very basic emulator of the ARM instruction set written in Golang
USAGE : ARMed [OPTIONS]... SOURCE_FILE

--all 		show all register values after an instruction, with updated ones in color
--end 		show updated registers only once, at the end of the program. Overrides --all
--no-log 	suppress logs of statements being executed
--help 		display help

Found a bug? Feel free to raise an issue on https://github.com/coderick14/ARMed
Contributions welcome :)

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Contributions

Found a bug? Or maybe add support for some more instructions? Feel free to open up a pull request or raise an issue!!

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NOTE : On Windows, if your cmd does not support unicode characters, pipe your output to a file.

ARMed.exe myfile > output.txt

Then view the file in your favourite editor (Notepad++, Wordpad, Sublime Text etc)

Instructions supported in v1.0

INSTRUCTION : ADDITION
Example : ADD X1, X2, X3
Meaning : X1 = X2 + X3

INSTRUCTION : SUBTRACTION
Example : SUB X1, X2, X3
Meaning : X1 = X2 - X3

INSTRUCTION : MULTIPLICATION 
Example : MUL X1, X2, X3
Meaning : X1 = X2 * X3

INSTRUCTION : ADD IMMEDIATE
Example : ADDI X1, X2, #40
Meaning : X1 = X2 + 40

INSTRUCTION : SUB IMMEDIATE
Example : SUBI X1, X2, #40
Meaning : X1 = X2 - 40

INSTRUCTION : ADD AND SET FLAGS
Example : ADDS X1, X2, X3
Meaning : X1 = X2 + X3
Comments : Adds and sets condition codes

INSTRUCTION : SUB AND SET FLAGS
Example : SUBS X1, X2, X3
Meaning : X1 = X2 - X3
Comments : Subtracts and sets condition codes

INSTRUCTION : ADD IMMEDIATE AND SET FLAGS
Example : ADDIS X1, X2, #40
Meaning : X1 = X2 + 40
Comments : Adds constant and sets condition codes

INSTRUCTION : SUB IMMEDIATE AND SET FLAGS
Example : SUBIS X1, X2, #40
Meaning : X1 = X2 - 40
Comments : Subtracts constant and sets condition codes

INSTRUCTION : LOAD
Example : LDUR X1, [X2, #40]
Meaning : X1 = Memory[X2 + 40]
Comments : Word from memory to register

INSTRUCTION : STORE
Example : STUR X1, [X2, #40]
Meaning : Memory[X2 + 40] = X1
Comments : Word from register to memory

INSTRUCTION : LOAD HALFWORD
Example : LDURH X1, [X2, #40]
Meaning : X1 = Memory[X2 + 40]
Comments : Halfword from memory to register

INSTRUCTION : STORE HALFWORD
Example : STURH X1, [X2, #40]
Meaning : Memory[X2 + 40] = X1
Comments : Halfword from register to memory

INSTRUCTION : LOAD BYTE
Example : LDURB X1, [X2, #40]
Meaning : X1 = Memory[X2 + 40]
Comments : Byte from memory to register

INSTRUCTION : STORE BYTE
Example : STURB X1, [X2, #40]
Meaning : Memory[X2 + 40] = X1
Comments : Byte from register to memory

INSTRUCTION : MOVE WITH ZERO
Example : MOVZ X1, 20, LSL 0
Meaning : X1 = 20 or 20*(2^16) or 20*(2^32) or 20*(2^48)
Comments : Loads 16-bit constant, rest zeroes

INSTRUCTION : MOVE WITH KEEP
Example : MOVK X1, 20, LSL 0
Meaning : X1 = 20 or 20*(2^16) or 20*(2^32) or 20*(2^48)
Comments : Loads 16-bit constant, rest unchanged

INSTRUCTION : LOGICAL AND
Example : AND X1, X2, X3
Meaning : X1 = X2 & X3
Comments : Bitwise-And of X2 and X3, stores result in X1

INSTRUCTION : LOGICAL OR
Example : ORR X1, X2, X3
Meaning : X1 = X2 | X3
Comments : Bitwise-Or of X2 and X3, stores result in X1

INSTRUCTION : LOGICAL EXCLUSIVE-OR
Example : EOR X1, X2, X3
Meaning : X1 = X2 ^ X3
Comments : Bitwise-Xor of X2 and X3, stores result in X1

INSTRUCTION : LOGICAL AND IMMEDIATE
Example : ANDI X1, X2, #20
Meaning : X1 = X2 & 20
Comments : Bitwise-And of X2 with a constant, stores result in X1

INSTRUCTION : LOGICAL OR IMMEDIATE
Example : ORRI X1, X2, #20
Meaning : X1 = X2 | 20
Comments : Bitwise-Or of X2 with a constant, stores result in X1

INSTRUCTION : LOGICAL EXCLUSIVE-OR IMMEDIATE
Example : EORI X1, X2, #20
Meaning : X1 = X2 ^ 20
Comments : Bitwise-Xor of X2 with a constant, stores result in X1

INSTRUCTION : LOGICAL LEFT SHIFT
Example : LSL X1, X2, #10
Meaning : X1 = X2 << 10
Comments : Left shifts X2 by a constant, stores result in X1

INSTRUCTION : LOGICAL RIGHT SHIFT
Example : LSR X1, X2, #10
Meaning : X1 = X2 >> 10
Comments : Right shifts X2 by a constant, stores result in X1

INSTRUCTION : COMPARE AND BRANCH ON EQUAL 0
Example : CBZ X1, label
Meaning : if (X1 == 0) go to label
Comments : Equal 0 test; PC-relative branch

INSTRUCTION : COMPARE AND BRANCH ON NOT EQUAL 0
Example : CBNZ X1, label
Meaning : if (X1 != 0) go to label
Comments : NotEqual 0 test; PC-relative branch

INSTRUCTION : CONDITIONAL BRANCH
Example : B.cond label
Meaning : if (condition true) go to label
Comments : Test condition codes; if true, then branch

INSTRUCTION : UNCONDITIONAL BRANCH
Example : B label
Meaning : go to label
Comments : Branch to PC-relative target address

INSTRUCTION : UNCONDITIONAL BRANCH TO REGISTER
Example : BR LR
Meaning : go to address stored in LR
Comments : Branch to address stored in register. Used for switch, procedure return

INSTRUCTION : UNCONDITIONAL BRANCH WITH LINK
Example : BL label
Meaning : X30 = PC + 4; go to label
Comments : For procedure call (PC-relative)