0x61nas

RFlags is like a veritable junk drawer of disjointed little bits of information. RFlags as a whole is a single 64-bit register buried inside he CPU. It's the 64-bit extension of the 32-bit EFlags register, which in turn is the 32-bit extension of the 16-bit Flags register. There's only 18 bits of the RFlags register are actually flags. The reset is reserved for later use in future generations of Intel CPUs. A flag is a single bit of information, whose meaning is independent from any other bits. A bit can be set to 1 or clered to 0 by the CPU as its needs require.

I	Shorthand	Name	Description
0	CF	Carry Flag	Used in assigned arithmetic operations. If the result of arithmetic or shift operation carries out a bit from the operand.
1	-	Undefind	-
2	PF	Parity Flag	Indecates whether the number of set (1) bits in the low-order byte of a result is even(set), or odd(cleard).

Instruction	Operands	Description
MOV	dist, source	Copy the data from the source to the distnation register or memory
INC	dist	Increment the distnation register or memory by one
DEC	dist	Decrement the distnation register or memory by one
JNZ	dist(label)	Tests the value of Zero Flag and jump to the distnation if its not set(a.k.a. set o 0)
JMP	dist	Always jump to its operand
ADD	dist, source	Add the source value to the distnation
NOP	n/a	No operation, it takes some time to execute

	{
	"timeStamp": 1700742074307,
	"version": "1.53.0",
	"userSettings": {
	"advancedUserEnabled": true,
	"cloudStorageEnabled": true,
	"externalLists": "https://raw.githubusercontent.com/LanikSJ/ubo-filters/main/filters/cdn-filter-list.txt\nhttps://raw.githubusercontent.com/LanikSJ/ubo-filters/main/filters/malware-domains.txt\nhttps://raw.githubusercontent.com/LanikSJ/ubo-filters/main/filters/popads-domains.txt\nhttps://raw.githubusercontent.com/LanikSJ/ubo-filters/main/filters/youtube-antiadblock.txt",
	"firewallPaneMinimized": false,
	"importedLists": [
	"https://raw.githubusercontent.com/LanikSJ/ubo-filters/main/filters/cdn-filter-list.txt",

	@startuml
	!theme sketchy-outline
	skinparam participantFontSize 19
	skinparam componentFontSize 19
	skinparam activityArrowFontSize 19
	skinparam actorFontSize 19
	skinparam databaseFontSize 19
	skinparam queueFontSize 19
	title Sequence digram

	; Data stored inside CPU register called _register data_.
	; and accessing register data directly is addressing mode called _register addressing_

	section .data
	section .text

	global .start
	start:
	mov rbp, rsi ; 64-bit
	mov ecx, edx ; 32-bit

	section .data
	section .text

	global .start
	start:
	; When you want to put the value 0 into a register, the fastest way is to use XOR.
	; XORing a value againsnt it self yields 0.
	xor rbx, rbx
	; Yes, you could use `mov rbx, 0` instnad, but that has to go out to memory to load the immediate value 0
	; XORing register against it self doesn't go out of the CPU for either the source or the destination, so its a little bit faster.

	; Print a message out
	; Aassmbl with:
	; nasm -f elf64 -g -F stabs eatsyscall.asm
	; ld -o eatsyscall eatsyscall.o

	section .data
	EatMsg: db "Eat at Joe's!", 10
	EatLen: equ $-EatMsg

	section .bss ; section containing the unintialized data

	; MOV instruction
	; Used to move a byte, word(16bit), double word(32bit), or quad word(64bit) from the source(second operand) to the dist(first operand).
	; Note that the MOV instruction cannot move data directly from one address in memory to different address in memory
	; to do that you need to _two separate MOV instructions: frst move the datat from the memory to some registry and then move it from that registry to the dist memory.
	; Assemble with:
	; nasm -f elf64 -g -F dwarf mov101.asm
	; ld -o mov101 mov101.o

	section .data
	section .text

	exit
	break start
	exit
	n
	i reg
	i reg cl
	i reg dh
	exit
	n
	i reg eax