global main extern sin extern printf section .data radian: dq 0.0 sine: dq 0.0 section .text pi: dq 3.141592653589793 delta: dq 18.0 ; One line moves pi/delta radians. two: dq 2.0 ; For 2π. middle: dq 5.0 ; For print column line: dq 10 dot: dq "•", 0 dash: dq "-", 0 bar: dq "|", 0 space: dq " ", 0 two_pi: dq "2π", 0 template: dq "%s", 0 new_line: dq "", 10, 0 main: push rbx ; convention mov rcx, [line] ; start rcx as counter push rcx ; save for later L0: movsd xmm0, [radian] ; mov current radian amount call sin ; Result in xmm0. movsd [sine], xmm0 ; Save to memory. movsd xmm0, [radian] ; reload radian amount movsd xmm1, [sine] ; load sine amount set_up_print: movsd xmm3, xmm1 ; save sine amount mulsd xmm1, [middle] ; compute coordinate point on printout addsd xmm1, [middle] cvtsd2si rdx, xmm1 pop rcx push rcx cmp rdx, rcx ; if current line has value at current radian je print_dot ; print point xorpd xmm4, xmm4 comisd xmm0, xmm4 ; if at left end je print_y_axis ; print y-axis cvtsd2si rdx, [middle] pop rcx cmp rcx, rdx ; if at middle push rcx je print_x_axis ; print x-axis jmp print_space ; else print space print_dot: mov rsi, dot jmp continue print_y_axis: mov rsi, bar jmp continue print_x_axis: mov rsi, dash jmp continue print_space: mov rsi, space continue: mov rdi, template ; prepare to print xor rax, rax sub rsp, 8 call printf add rsp, 8 movsd xmm1, xmm3 movsd xmm0, [radian] movsd xmm1, [pi] divsd xmm1, [delta] addsd xmm0, xmm1 ; radian += pi/delta movsd [radian], xmm0 movsd xmm2, [pi] mulsd xmm2, [two] addsd xmm1, xmm2 ; 2*pi + pi/delta comisd xmm0, xmm1 jc L0 ; loop back on current line to continute plotting cvtsd2si rdx, [middle] ; if at end of middle+1 line dec rdx pop rcx cmp rcx, rdx push rcx jne not_axis mov rsi, two_pi mov rdi, template xor rax, rax sub rsp, 8 call printf ; print "2π" add rsp, 8 not_axis: mov rsi, new_line ; if at end of line mov rdi, template xor rax, rax sub rsp, 8 call printf ; print new line add rsp, 8 xorpd xmm0, xmm0 movsd [radian], xmm0 movsd [sine], xmm0 pop rcx ; decrement line count dec rcx xor r12, r12 ; if at end of plotting cmp rcx, r12 push rcx jge L0 ; loop back to continue plotting next line pop rcx pop rbx ; convention ret
Write, Run & Share Assembly code online using OneCompiler's Assembly online compiler for free. It's one of the robust, feature-rich online compilers for Assembly language. Getting started with the OneCompiler's Assembly compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as Assembly and start coding.
Assembly language(asm) is a low-level programming language, where the language instructions will be more similar to machine code instructions.
Every assembler may have it's own assembly language designed for a specific computers or an operating system.
Assembly language requires less execution time and memory. It is more helful for direct hardware manipulation, real-time critical applications. It is used in device drivers, low-level embedded systems etc.
Assembly language usually consists of three sections,
Data section
To initialize variables and constants, buffer size these values doesn't change at runtime.
bss section
To declare variables
text section
_start specifies the starting of this section where the actually code is written.
There are various define directives to allocate space for variables for both initialized and uninitialized data.
variable-name define-directive initial-value
| Define Directive | Description | Allocated Space |
|---|---|---|
| DB | Define Byte | 1 byte |
| DW | Define Word | 2 bytes |
| DD | Define Doubleword | 4 bytes |
| DQ | Define Quadword | 8 bytes |
| DT | Define Ten Bytes | 10 bytes |
| Define Directive | Description |
|---|---|
| RESB | Reserve a Byte |
| RESW | Reserve a Word |
| RESD | Reserve a Doubleword |
| RESQ | Reserve a Quadword |
| REST | Reserve a Ten Bytes |
Constants can be defined using
CONSTANT_NAME EQU regular-exp or value
%assign constant_name value
%define constant_name value
Loops are used to iterate a set of statements for a specific number of times.
mov ECX,n
L1:
;<loop body>
loop L1
where n specifies the no of times loops should iterate.
Procedure is a sub-routine which contains set of statements. Usually procedures are written when multiple calls are required to same set of statements which increases re-usuability and modularity.
procedure_name:
;procedure body
ret