Directives

Venus supports most common assembler directives, including some indicated here.

.file

Emits filename.

Usage

.file <filename>

Example

.file "/home/ubuntu/Desktop/lab10.s"

Arguments

• filename: quoted filename

Aliases

• none

.zero

Reserves the specified number of bytes.

Usage

.zero <value>

Example

.zero 10 # reserves 10 bytes

Arguments

• value: (should be > 0)

Aliases

• .space

.string

Stores the string and adds null terminator.

Usage

.string <string>

Example

.string "hello world" 

Arguments

• string: quoted string

Aliases

• .asciiz, .asciz

.ascii

Stores the string and does not add null terminator.

Usage

.ascii <string>

Example

.ascii "Hello world"

Arguments

• string: quoted string

Aliases

• none

.byte

Store the listed value(s) as 8 bit bytes.

Usage

.byte <list>

Example

.byte 10, 50
.byte 2

Arguments

• list: 8-bit comma separated bytes

Aliases

• none

.half

Store the listed value(s) as 16-bit half words.

Usage

.half <list>

Example

.half 1, 2, 3
.half 10

Arguments

• list: 16-bit comma separated half words

Aliases

• .short, .2byte

.word

Store the listed value(s)/symbol(s) as 32 bit words.

Usage

.word <list>

Example

.word 1, 3, 5, 7
.word 0xcafe

Arguments

• list: 32-bit comma separated words or comma separated symbols

Aliases

• .long, .4byte

.float

Store the listed value(s) as 32 bit float values.

Usage

.float <list>

Example

.float 1e-4, 1.2, 0.005
.float 3.1416

Arguments

• list: 32-bit comma separated float words

Aliases

• none

.align

Align next data item to a power of 2 byte boundary.

Usage

.align <alignval>

Example

.align 2 # 2 ^ 2 = 4 (word align)

Arguments

• alignval: integer, should be >= 0

Aliases

• .palign

.balign

Align next data item to a byte boundary.

Usage

.balign <alignval>

Example

.balign 4 # 4 bytes (word align)

Arguments

• alignval: integer, should be > 0

Aliases

• none

.globl

Store the symbol in the global symbol table.

Usage

.globl <symbol>

Example

.globl foo

Arguments

• symbol: symbol to store in global symbol table

Aliases

• .global

.section

Emits the specified section and makes it the current section.

Usage

.section <section>

Example

.section .text
    li a0, 10
.section .data
    msg: .string "hello"
.section .rodata
    num: .word 10 
.section .bss
    array: .zero 40

Arguments

• section: {.text, .data, .rodata, .bss}

Aliases

• none

.data

Emits data section and makes it the current section.

Usage

.data

Example

.data
    msg: .string "hello"

Arguments

• none

Aliases

• none

.text

Emits text section and makes it the current section.

Usage

.text

Example

.text
    li a0, 10
    ecall

Arguments

• none

Aliases

• none

.rodata

Emits read-only data section and makes it the current section.

Usage

.rodata

Example

.rodata
    msg: .string "hello"

Arguments

• none

Aliases

• none

.bss

Emits bss section and makes it the current section.

Usage

.bss

Example

.bss
    array: .zero 40

Arguments

• none

Aliases

• none