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#include "helpers/function.S"
#include "SDL/events.S"
#include "SDL/init.S"
#include "SDL/rect.S"
#include "SDL/render.S"
#include "SDL/video.S"
#define SCREEN_WIDTH 800
#define SCREEN_HEIGHT 600
// integer-params: RDI, RSI, RDX, RCX, R8, R9
// caller-saved: RAX, RCX, RDI, RSI, RDX, R8-R11
// callee-saved: RBX, RSP, RBP, R12-R15
.section .rodata
failed_to_create_renderer: .string "Renderer could not be created\nSDL_error: %s\n"
failed_to_create_window: .string "Window could not be created\nSDL_error: %s\n"
failed_to_initialize_sdl: .string "SDL could not be initialized\nSDL_error: %s\n"
succeeded_to_create_renderer: .string "Renderer created successfully!\n"
succeeded_to_create_window: .string "Window created successfully!\n"
succeeded_to_initialize_sdl: .string "SDL2 initialized successfully!\n"
window_title: .string "snake.s"
.section .text
function_begin main
push %r12
push %r13
define_local window_handle, 8
define_local renderer_handle, 8
define_local rect, SIZE_SDL_Rect
define_local event, SIZE_SDL_Event
allocate_locals
// initialize SDL
mov $SDL_INIT_VIDEO, %rdi
call SDL_Init@PLT
// check if initialization was successful
test %rax, %rax
jae 1f
lea failed_to_initialize_sdl(%rip), %rdi
call _print_sdl_error@PLT
mov $1, %rax
function_exit
1:
lea succeeded_to_initialize_sdl(%rip), %rdi
xor %rax, %rax
call printf@PLT
// create a window
lea window_title(%rip), %rdi
mov $SDL_WINDOWPOS_UNDEFINED, %rsi
mov $SDL_WINDOWPOS_UNDEFINED, %rdx
mov $SCREEN_WIDTH, %rcx
mov $SCREEN_HEIGHT, %r8
mov $SDL_WINDOW_SHOWN, %r9
call SDL_CreateWindow@PLT
store_local %rax, window_handle
// check if window creation was successful
test %rax, %rax
jne 1f
lea failed_to_create_window(%rip), %rdi
call _print_sdl_error@PLT
mov $1, %rax
jmp .Lquit_sdl
1:
lea succeeded_to_create_window(%rip), %rdi
xor %rax, %rax
call printf@PLT
// create a renderer
load_local window_handle, %rdi
mov $-1, %rsi
mov $(SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC), %rdx
call SDL_CreateRenderer@PLT
store_local %rax, renderer_handle
// check if renderer creation was successful
test %rax, %rax
jne 1f
lea failed_to_create_renderer(%rip), %rdi
call _print_sdl_error@PLT
jmp .Ldestroy_window
1:
lea succeeded_to_create_renderer(%rip), %rdi
xor %rax, %rax
call printf@PLT
// initialize a simple square, located at the screen's center
mov $(SCREEN_HEIGHT / 2), %r8d
mov $(SCREEN_WIDTH / 2), %r9d
address_of_local rect, %rdi
mov %r8d, OFFSET_SDL_Rect_w(%rdi)
mov %r8d, OFFSET_SDL_Rect_h(%rdi)
mov %r9d, %r10d
shr $1, %r8d
sub %r8d, %r10d
mov %r10d, OFFSET_SDL_Rect_x(%rdi)
mov %r8d, OFFSET_SDL_Rect_y(%rdi)
//! @var bool quit_requested
xor %r12, %r12
// main loop
.Lloop:
address_of_local event, %rdi
mov %rdi, %r13
call SDL_PollEvent@PLT
mov (%r13), %r8d
// user requested to quit
cmp $SDL_EVENT_QUIT, %r8d
je .Lloop_end
// use white color
load_local renderer_handle, %rdi
mov %rdi, %r13
mov $0xff, %rsi
mov %rsi, %rdx
mov %rsi, %rcx
mov %rsi, %r8
call SDL_SetRenderDrawColor@PLT
test %rax, %rax
// clear the screen
mov %r13, %rdi
call SDL_RenderClear@PLT
// use red color
mov %r13, %rdi
mov $0xff, %rsi
mov $0x00, %rdx
mov $0x00, %rcx
mov %rsi, %r8
call SDL_SetRenderDrawColor@PLT
// draw the square
mov %r13, %rdi
address_of_local rect, %rsi
call SDL_RenderFillRect@PLT
// update the screen
mov %r13, %rdi
call SDL_RenderPresent@PLT
jmp .Lloop
.Lloop_end:
.Ldestroy_renderer:
// destroy the renderer
load_local renderer_handle, %rdi
call SDL_DestroyRenderer@PLT
.Ldestroy_window:
// destroy the window
load_local window_handle, %rdi
call SDL_DestroyWindow@PLT
.Lquit_sdl:
call SDL_Quit@PLT
xor %rax, %rax
pop %r13
pop %r12
function_end
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