25 lines
896 B
ArmAsm
25 lines
896 B
ArmAsm
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/*
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Lines enclosed here are comments
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A small program: prints "Hello World!"
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*/
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// From // to the end of this line is a comment: next are directives to the assembler
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.equ SYS_EXIT, 93
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.equ SYS_WRITE, 64
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.data // tells assembler to assemble the following in the data section
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msg: .asciz "Hello World!\n" //msg retains the address of the string
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.text // tells assembler to assemble the following
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// in the text (code) section
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.globl _start // _start is there where the program starts,
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// .globl makes it visible to the linker
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_start:
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mov x0,#1 // value 1 is placed in register x0
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adr x1,msg // the address retained by label msg is placed in register x1
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mov x2,#13
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mov w8, #SYS_WRITE // svc must find the syscall number in w8
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// and the syscall arguments in x0,x1,x2
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svc #0 // invoke syscall: displays on the screen
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mov x0, #0 // in x0 put the value you want to exit with
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mov w8,#SYS_EXIT
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svc #0
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.end
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