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//! @file snake.S
//!
//! Type definitions, sizes, and the interface for the snake.
#include "helpers/function.S"
#define OFFSET_snake_t_x 0
#define SIZE_snake_t_x 4
#define OFFSET_snake_t_y OFFSET_snake_t_x + SIZE_snake_t_x
#define SIZE_snake_t_y 4
#define OFFSET_snake_t_length OFFSET_snake_t_y + SIZE_snake_t_y
#define SIZE_snake_t_length 4
#define OFFSET_snake_t_direction OFFSET_snake_t_length + SIZE_snake_t_length
#define SIZE_snake_t_direction 1
#define OFFSET_snake_t_padding OFFSET_snake_t_direction + SIZE_snake_t_direction
#define SIZE_snake_t_padding 3
#define SIZE_snake_t OFFSET_snake_t_padding + SIZE_snake_t_padding
#ifndef __STDC_VERSION__
.section .text
//! @fn void snake_init(snake_t * self, int x, int y, int length)
//! @param (%rdi) self the object to initialize
//! @param (%esi) x the x position of the head of the snake
//! @param (%edx) y the y position of the head of the snake
//! @param (%ecx) length the length of the snake
function_begin snake_init
test %rdi, %rdi
jz .Lexit_snake_init
mov %esi, OFFSET_snake_t_x(%rdi)
mov %edx, OFFSET_snake_t_y(%rdi)
mov %ecx, OFFSET_snake_t_length(%rdi)
xor %al, %al
mov %al, OFFSET_snake_t_direction(%rdi)
function_end
#else
#include <stddef.h>
typedef struct {
int x;
int y;
int length;
char direction;
char padding[3];
} snake_t;
static_assert(sizeof(snake_t) == SIZE_snake_t);
static_assert(offsetof(snake_t, x) == OFFSET_snake_t_x);
static_assert(sizeof(((snake_t*)0)->x) == SIZE_snake_t_x);
static_assert(offsetof(snake_t, y) == OFFSET_snake_t_y);
static_assert(sizeof(((snake_t*)0)->y) == SIZE_snake_t_y);
static_assert(offsetof(snake_t, length) == OFFSET_snake_t_length);
static_assert(sizeof(((snake_t*)0)->length) == SIZE_snake_t_length);
static_assert(offsetof(snake_t, direction) == OFFSET_snake_t_direction);
static_assert(sizeof(((snake_t*)0)->direction) == SIZE_snake_t_direction);
static_assert(offsetof(snake_t, padding) == OFFSET_snake_t_padding);
static_assert(sizeof(((snake_t*)0)->padding) == SIZE_snake_t_padding);
void snake_init(snake_t * self, int x, int y, int length);
#endif
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