#ifndef _ASM_H
#define _ASM_H

#include <stddef.h>
#include <stdint.h>

typedef size_t ip;
extern ip here;

// A general-purpose x86 register.
// The specific register size (e.g. al/ax/eax/rax) depends on the instruction.
// All registers are valid for all instructions; we will perform exchanges if necessary.
typedef enum reg {
    RA = 0, // rax, eax, ax, al
    RC = 1, // rcx, ecx, cx, cl
    RD = 2, // rdx, edx, dx, dl
    RB = 3, // rbx, ebx, bx, bl
    SP = 4, // rsp, esp, sp, spl (we do not use ah)
    BP = 5, // rbp, ebp, bp, bpl (we do not use ch)
    SI = 6, // rsi, esi, si, sil (we do not use dh)
    DI = 7, // rdi, edi, di, dil (we do not use bh)
    R8 = 8, // r8, r8d, r8w, r8l
    R9 = 9, // r9, r9d, r9w, r9l
    R10 = 10, // r10, r10d, r10w, r10l
    R11 = 11, // r11, r11d, r11w, r11l
    R12 = 12, // r12, r12d, r12w, r12l
    R13 = 13, // r13, r13d, r13w, r13l
    R14 = 14, // r14, r14d, r14w, r14l
    R15 = 15, // r15, r15d, r15w, r15l
} reg;

/// Jump to a known address.
void inst_jump(ip there);

/// Jump to an unresolved address.
ip inst_jump_unresolved(void);
void inst_jump_resolve(ip disp, ip there);

void inst_mov_imm(reg reg, uint64_t imm);
void inst_mov_imm_i64(reg reg, int64_t imm);
void inst_syscall(void);

void inst_push(reg reg);
void inst_pop(reg reg);

void inst_mov(reg dest, reg src);
void inst_mov_from(reg dest, reg base);
void inst_mov_from_disp(reg dest, reg base, int32_t disp);
void inst_mov_to(reg base, reg src);
void inst_mov_to_disp(reg base, reg src, int32_t disp);
#endif