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Low-Level

This page is still under construction!

Abstractions are made to make the programmer's life easier, symplifying repedititve or system-dependent tasks.

Sometimes however, it is mandatory to communicate directly with the system. Embedded and bare-metal development, system programming and better memory managing are just some examples of why this access is needed.

Acessing CPU Registers​

This feature is still not implemented!

When compiled to some CPUs, the program binary has access to a set of CPU Registers that are used to do operations or controll the CPU behavior.

// TODO

Inline Assembly​

This feature is still not implemented!

When read and write to the registers themselves are not enough, Abstract has a rich system that allow the user to write an entire assembly subroutine.

As a example of use, being targeted to x86_64 assemby:

from Std.Console import
from Std.System.Assembly.x86_64Assembly import { assemblyContext }

func foo() {

	let string message = "Hello, World!"

	# Calling writeln(message) though assembly

	# This will create the context object.
	# The context object is used to store the
	# entire assembly code in a tiny scope,
	# allowing that the code will be emited as
	# is and do not receive any optimizations.
	assemblyContext()

	# The context return an instance that contains
	# diverse methods to write the assembly code.
	# See the example:

	# The first argument must go in the RAX register
	# the mov instruction follows the order 'to <- from'
	.MOV(.rax, message)
	# Then we can make a call to the function pointer
	.CALL(&writeln)

	#This is equivalent to
	###
		MOV $rax, message
		CALL Std.Console.writeln
	###

}
from Std.Console import
from Std.System.Assembly.x86_64Assembly import { assemblyContext }

func say_message(string message) {

	assemblyContext()

	# This code makes a system call in a linux environment.
	# This code is also targeted to x86 machines.

	.MOV(.eax, 4) # sys_write
	.MOV(.ebx, 1) # stdout
	.MOV(.ecx, message.buffer)
	.MOV(.edx, message.length)
	.INT(0x80)

}