Add Hello World program in assembly (MacOS and Linux)

helloworld.asm

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+; How to run assembler code on Linux
+; nasm -f elf64 helloworld.asm -o helloworld.o
+; ld helloworld.o -o helloworld
+; ./helloworld
+
+section .data
+	msg db "Hello, World!", 10
+
+section .text
+	global _start
+
+_start:
+	mov rax, 1
+	mov rdi, 1
+	mov rsi, msg
+	mov rdx, 14
+	syscall
+
+	mov rax, 60
+	xor rdi, rdi
+	syscall

helloworld.s

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+// How to run assembler code on MacOS:
+// as helloworld.s -o helloworld.o
+// ld helloworld.o -o helloworld -lSystem -syslibroot $(xcrun -sdk macosx --show-sdk-path) -e _start -arch arm64
+// ./helloworld
+
+.global _start
+.align 2
+
+_start:
+    mov x0, #1
+    adr x1, msg
+    mov x2, #14
+    mov x16, #4
+    svc #0x80
+
+    mov x0, #0
+    mov x16, #1
+    svc #0x80
+
+msg:
+    .ascii "Hello, World!\n"
+