split up assembler

asm/assemble.c

@@ -0,0 +1,686 @@
+#include "asm.h"
+#include "eval.h"
+#include "parse.h"
+#include "report.h"
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+typedef enum {
+    // clang-format off
+    M_err, M_d8, M_d16, M_nop, M_hlt, M_jmp,
+    M_jmpf, M_jnz, M_cmp, M_mov, M_in, M_out,
+    M_call, M_callf, M_ret, M_retf, M_lit, M_int,
+    M_iret, M_or, M_xor, M_and, M_shl, M_rshl,
+    M_shr, M_rshr, M_add, M_sub, M_rsub, M_mul,
+    M_imul, M_div, M_idiv, M_rdiv, M_ridiv, M_mod,
+    M_rmod, M_push, M_pop
+    // clang-format on
+} Mnemonic;
+
+static const char* mnemonic_str[] = {
+    // clang-format off
+    "err", "d8", "d16", "nop", "hlt", "jmp",
+    "jmpf", "jnz", "cmp", "mov", "in", "out",
+    "call", "callf", "ret", "retf", "lit", "int",
+    "iret", "or", "xor", "and", "shl", "rshl",
+    "shr", "rshr", "add", "sub", "rsub", "mul",
+    "imul", "div", "idiv", "rdiv", "ridiv", "mod",
+    "rmod", "push", "pop"
+    // clang-format on
+};
+
+uint16_t pline_assemble(OperandEvaluator* evaluator,
+    uint16_t* object,
+    const PLine* line,
+    Reporter* rep)
+{
+
+#define CHECK_OPERAND(OP)                                                      \
+    do {                                                                       \
+        if ((OP).ty == EoTy_Err) {                                             \
+            return 0;                                                          \
+        }                                                                      \
+    } while (0)
+
+#define ASSEMBLE_ONE(RVAL)                                                     \
+    do {                                                                       \
+        Line l = (RVAL);                                                       \
+        return assemble_line(object, &l);                                      \
+    } while (0)
+
+    size_t mnemonics_amount = sizeof(mnemonic_str) / sizeof(mnemonic_str[0]);
+    Mnemonic m = M_err;
+    for (size_t i = 0; i < mnemonics_amount; ++i) {
+        if (strcmp(mnemonic_str[i], line->op) == 0) {
+            m = (Mnemonic)i;
+            break;
+        }
+    }
+    switch (m) {
+        case M_err: {
+            REPORTF_ERROR("unrecognized mnemonic '%s'", line->op);
+            reporter_print_loc(rep, line->loc);
+            return 0;
+        }
+        case M_d8: {
+            if (line->ops_size > 64) {
+                reporter_error_with_loc(
+                    rep, "too many operands (max is 64)", line->loc);
+                return 0;
+            }
+            size_t buffer_capacity = 128;
+            uint8_t* buffer = malloc(sizeof(uint8_t) * buffer_capacity);
+            size_t buffer_size = 0;
+            for (size_t i = 0; i < line->ops_size; ++i) {
+                EvaledOperand val = eval_operand(evaluator, line->ops[i]);
+                CHECK_OPERAND(val);
+                switch (val.ty) {
+                    case EoTy_Imm:
+                        buffer[buffer_size++] = (uint8_t)val.imm;
+                        break;
+                    case EoTy_Str: {
+                        for (size_t si = 0; si < line->ops[i]->str_len; ++si) {
+                            buffer[buffer_size++]
+                                = (uint8_t)line->ops[i]->str[si];
+                        }
+                        break;
+                    }
+                    default:
+                        reporter_error_with_loc(
+                            rep, "invalid operand", line->ops[i]->loc);
+                        return 0;
+                }
+            }
+            uint16_t ip_diff = 0;
+            for (size_t i = 0; i < buffer_size; i += 2) {
+                uint16_t data = 0;
+                // XXX: little endian
+                data |= buffer[i];
+                if (i + 1 < buffer_size) {
+                    data |= (uint16_t)((uint16_t)buffer[i] << 8);
+                }
+                Line l = s_data_i(data);
+                ip_diff += assemble_line(object, &l);
+            }
+            return ip_diff;
+        }
+        case M_d16: {
+            if (line->ops_size > 32) {
+                reporter_error_with_loc(
+                    rep, "too many operands (max is 32)", line->loc);
+                return 0;
+            }
+            uint16_t ip_diff = 0;
+            for (size_t i = 0; i < line->ops_size; ++i) {
+                EvaledOperand val = eval_operand(evaluator, line->ops[i]);
+                CHECK_OPERAND(val);
+                switch (val.ty) {
+                    case EoTy_Imm: {
+                        Line l = s_data_i(val.imm);
+                        ip_diff += assemble_line(object, &l);
+                        break;
+                    }
+                    default:
+                        reporter_error_with_loc(
+                            rep, "invalid operand", line->ops[i]->loc);
+                        return 0;
+                }
+            }
+            return ip_diff;
+        }
+        case M_nop:
+            if (line->ops_size == 0)
+                ASSEMBLE_ONE(s_nop());
+            break;
+        case M_hlt:
+            if (line->ops_size == 0)
+                ASSEMBLE_ONE(s_hlt());
+            break;
+        case M_jmp:
+            if (line->ops_size == 1) {
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(op1);
+                if (op1.ty == EoTy_Reg)
+                    ASSEMBLE_ONE(s_jmp_r(op1.reg));
+                if (op1.ty == EoTy_Imm)
+                    ASSEMBLE_ONE(s_jmp_i(op1.imm));
+            }
+            break;
+        case M_jmpf:
+            if (line->ops_size == 2) {
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op2);
+                if (op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_jmpf_r_r(op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_jmpf_r_i(op1.reg, op2.imm));
+                }
+                if (op1.ty == EoTy_Imm) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_jmpf_i_r(op1.imm, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_jmpf_i_i(op1.imm, op2.imm));
+                }
+            }
+            break;
+        case M_jnz:
+            if (line->ops_size == 2) {
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op2);
+                if (op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_jnz_r(op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_jnz_i(op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_cmp:
+            if (line->ops_size == 2) {
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op2);
+                if (op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_cmp_r(op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_cmp_i(op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_mov:
+            if (line->ops_size == 2) {
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op2);
+                if (op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_mov16_r_r(op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_mov16_r_i(op1.reg, op2.imm));
+                    if (op2.ty == EoTy_Mem8Reg)
+                        ASSEMBLE_ONE(s_mov8_r_mr(op1.reg, op2.reg, op2.offset));
+                    if (op2.ty == EoTy_Mem8Imm)
+                        ASSEMBLE_ONE(s_mov8_r_mi(op1.reg, op2.imm));
+                    if (op2.ty == EoTy_MemU16Reg)
+                        ASSEMBLE_ONE(
+                            s_mov16_r_mr(op1.reg, op2.reg, op2.offset));
+                    if (op2.ty == EoTy_MemU16Imm) {
+                        ASSEMBLE_ONE(s_mov16_r_mi(op1.reg, op2.imm));
+                    }
+                }
+                if (op1.ty == EoTy_Mem8Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_mov8_mr_r(op1.reg, op1.offset, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_mov8_mr_i(op1.reg, op1.offset, op2.imm));
+                }
+                if (op1.ty == EoTy_Mem8Imm) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_mov8_mi_r(op1.imm, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_mov8_mi_i(op1.imm, op2.imm));
+                }
+                if (op1.ty == EoTy_MemU16Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(
+                            s_mov16_mr_r(op1.reg, op1.offset, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(
+                            s_mov16_mr_i(op1.reg, op1.offset, op2.imm));
+                }
+                if (op1.ty == EoTy_MemU16Imm) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_mov16_mi_r(op1.imm, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_mov16_mi_i(op1.imm, op2.imm));
+                }
+            }
+            break;
+        case M_in:
+            if (line->ops_size == 2) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                if (dst.ty == EoTy_Reg) {
+                    if (op1.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_in_r(dst.reg, op1.reg));
+                    if (op1.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_in_i(dst.reg, op1.imm));
+                }
+            }
+            break;
+        case M_out:
+            if (line->ops_size == 2) {
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op2);
+                if (op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_out_r_r(op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_out_r_i(op1.reg, op2.imm));
+                }
+                if (op1.ty == EoTy_Imm) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_out_i_r(op1.imm, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_out_i_i(op1.imm, op2.imm));
+                }
+            }
+            break;
+        case M_call:
+            if (line->ops_size == 1) {
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(op1);
+                if (op1.ty == EoTy_Reg)
+                    ASSEMBLE_ONE(s_call_r(op1.reg));
+                if (op1.ty == EoTy_Imm)
+                    ASSEMBLE_ONE(s_call_i(op1.imm));
+            }
+            break;
+        case M_callf:
+            if (line->ops_size == 2) {
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op2);
+                if (op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_callf_r_r(op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_callf_r_i(op1.reg, op2.imm));
+                }
+                if (op1.ty == EoTy_Imm) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_callf_i_r(op1.imm, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_callf_i_i(op1.imm, op2.imm));
+                }
+            }
+            break;
+        case M_ret:
+            if (line->ops_size == 0) {
+                ASSEMBLE_ONE(s_ret());
+            }
+            break;
+        case M_retf:
+            if (line->ops_size == 0) {
+                ASSEMBLE_ONE(s_retf());
+            }
+            break;
+        case M_lit:
+            if (line->ops_size == 1) {
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(op1);
+                if (op1.ty == EoTy_Reg)
+                    ASSEMBLE_ONE(s_lit_r(op1.reg));
+                if (op1.ty == EoTy_Imm)
+                    ASSEMBLE_ONE(s_lit_i(op1.imm));
+            }
+            break;
+        case M_int:
+            if (line->ops_size == 1) {
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(op1);
+                if (op1.ty == EoTy_Imm) {
+                    if (op1.imm > 0xff) {
+                        reporter_error_with_loc(
+                            rep, "interrupt id exceeds 1 byte", line->loc);
+                        return 0;
+                    }
+                    ASSEMBLE_ONE(s_int((uint8_t)op1.imm));
+                }
+            }
+            break;
+        case M_iret:
+            if (line->ops_size == 0) {
+                ASSEMBLE_ONE(s_iret());
+            }
+            break;
+        case M_or:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_or_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm) {
+                        ASSEMBLE_ONE(s_or_i(dst.reg, op1.reg, op2.imm));
+                    }
+                }
+            }
+            break;
+        case M_xor:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_xor_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_xor_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_and:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_and_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_and_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_shl:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_shl_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_shl_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_rshl:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_rshl_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_rshl_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_shr:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_shr_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_shr_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_rshr:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_rshr_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_rshr_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_add:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_add_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_add_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_sub:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_sub_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_sub_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_rsub:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_rsub_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_rsub_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_mul:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_mul_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_mul_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_imul:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_imul_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_imul_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_div:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_div_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_div_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_idiv:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_idiv_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_idiv_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_rdiv:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_rdiv_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_rdiv_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_ridiv:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_ridiv_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_ridiv_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_mod:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_mod_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_mod_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_rmod:
+            if (line->ops_size == 3) {
+                EvaledOperand dst = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(dst);
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[1]);
+                CHECK_OPERAND(op1);
+                EvaledOperand op2 = eval_operand(evaluator, line->ops[2]);
+                CHECK_OPERAND(op2);
+                if (dst.ty == EoTy_Reg && op1.ty == EoTy_Reg) {
+                    if (op2.ty == EoTy_Reg)
+                        ASSEMBLE_ONE(s_rmod_r(dst.reg, op1.reg, op2.reg));
+                    if (op2.ty == EoTy_Imm)
+                        ASSEMBLE_ONE(s_rmod_i(dst.reg, op1.reg, op2.imm));
+                }
+            }
+            break;
+        case M_push:
+            if (line->ops_size == 1) {
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(op1);
+                if (op1.ty == EoTy_Reg) {
+                    uint16_t size = 0;
+                    Line l;
+                    l = s_add_i(Rsp, Rsp, 2);
+                    size += assemble_line(object, &l);
+                    l = s_mov16_mr_r(Rsp, 0, op1.reg);
+                    size += assemble_line(object, &l);
+                    return size;
+                }
+                if (op1.ty == EoTy_Imm) {
+                    uint16_t size = 0;
+                    Line l;
+                    l = s_add_i(Rsp, Rsp, 2);
+                    size += assemble_line(object, &l);
+                    l = s_mov16_mr_i(Rsp, 0, op1.imm);
+                    size += assemble_line(object, &l);
+                    return size;
+                }
+            }
+            break;
+        case M_pop:
+            if (line->ops_size == 1) {
+                EvaledOperand op1 = eval_operand(evaluator, line->ops[0]);
+                CHECK_OPERAND(op1);
+                if (op1.ty == EoTy_Reg) {
+                    uint16_t size = 0;
+                    Line l;
+                    l = s_mov16_r_mr(op1.reg, Rsp, 0);
+                    size += assemble_line(object, &l);
+                    l = s_sub_i(Rsp, Rsp, 2);
+                    size += assemble_line(object, &l);
+                    return size;
+                }
+            }
+            break;
+    }
+    reporter_error_with_loc(rep, "malformed instruction", line->loc);
+    return 0;
+
+#undef CHECK_OPERAND
+#undef ASSEMBLE_ONE
+}

asm/assemble.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include "eval.h"
+#include "parse.h"
+#include "report.h"
+#include <stdint.h>
+
+uint16_t pline_assemble(OperandEvaluator* evaluator,
+    uint16_t* object,
+    const PLine* line,
+    Reporter* rep);

asm/eval.c

@@ -0,0 +1,304 @@
+#include "eval.h"
+#include "parse.h"
+#include "report.h"
+#include "resolve.h"
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+static inline uint16_t eval_poperandty_unary(POperandTy ty, uint16_t operand)
+{
+    switch (ty) {
+        case PoTy_Not:
+            return ~operand;
+        case PoTy_Negate:
+            return (uint16_t)-(int16_t)operand;
+        default:
+            return 0;
+    }
+}
+
+static inline uint16_t eval_poperandty_binary(
+    POperandTy ty, uint16_t left, uint16_t right)
+{
+    switch (ty) {
+        case PoTy_Or:
+            return left | right;
+        case PoTy_Xor:
+            return left ^ right;
+        case PoTy_And:
+            return left & right;
+        case PoTy_Shl:
+            return (uint16_t)(left << right);
+        case PoTy_Shr:
+            return (uint16_t)(left >> right);
+        case PoTy_Add:
+            return (uint16_t)((int16_t)left + (int16_t)right);
+        case PoTy_Sub:
+            return (uint16_t)((int16_t)left - (int16_t)right);
+        case PoTy_Mul:
+            return (uint16_t)((int16_t)left * (int16_t)right);
+        case PoTy_Div:
+            return (uint16_t)((int16_t)left / (int16_t)right);
+        case PoTy_Mod:
+            return (uint16_t)((int16_t)left % (int16_t)right);
+        default:
+            return 0;
+    }
+}
+
+EvaledOperand eval_operand_to_imm(
+    OperandEvaluator* evaluator, POperand* operand)
+{
+    switch (operand->ty) {
+        case PoTy_Str:
+            REPORTF_ERROR("%s", "strings cannot be part of expressions");
+            reporter_print_loc(evaluator->rep, operand->loc);
+            return (EvaledOperand) { .ty = EoTy_Err };
+        case PoTy_Mem8:
+        case PoTy_Mem16:
+            REPORTF_ERROR("%s", "indirections cannot be part of expressions");
+            reporter_print_loc(evaluator->rep, operand->loc);
+            return (EvaledOperand) { .ty = EoTy_Err };
+        case PoTy_Reg:
+            REPORTF_ERROR("%s", "registers cannot be part of expressions");
+            reporter_print_loc(evaluator->rep, operand->loc);
+            return (EvaledOperand) { .ty = EoTy_Err };
+        case PoTy_Imm:
+            return (EvaledOperand) { .ty = EoTy_Imm, .imm = operand->imm };
+        case PoTy_Ident:
+        case PoTy_SubLabel: {
+            const IdentResol* re
+                = ident_resolver_resolve(evaluator->re, operand->str);
+            if (re == NULL) {
+                if (!evaluator->second_pass) {
+                    return (EvaledOperand) { .ty = EoTy_Imm, .imm = 0 };
+                }
+                REPORTF_ERROR("undefined identifier '%s'", operand->str);
+                reporter_print_loc(evaluator->rep, operand->loc);
+                return (EvaledOperand) { .ty = EoTy_Err };
+            }
+            switch (re->ty) {
+                case IdentResolTy_None:
+                    break;
+                case IdentResolTy_Label:
+                case IdentResolTy_SubLabel:
+                    return (EvaledOperand) { .ty = EoTy_Imm, .imm = re->ip };
+            }
+            fprintf(stderr, "unreachable\n");
+            exit(1);
+        }
+        case PoTy_Not:
+        case PoTy_Negate: {
+            EvaledOperand inner
+                = eval_operand_to_imm(evaluator, operand->operand);
+            if (inner.ty == EoTy_Err) {
+                return inner;
+            } else if (inner.ty != EoTy_Imm) {
+                REPORTF_ERROR("%s", "operand cannot be used in expressions");
+                reporter_print_loc(evaluator->rep, operand->operand->loc);
+                return (EvaledOperand) { .ty = EoTy_Err };
+            }
+            return (EvaledOperand) {
+                .ty = EoTy_Imm,
+                .imm = eval_poperandty_unary(operand->ty, inner.imm),
+            };
+        }
+        case PoTy_Or:
+        case PoTy_Xor:
+        case PoTy_And:
+        case PoTy_Shl:
+        case PoTy_Shr:
+        case PoTy_Add:
+        case PoTy_Sub:
+        case PoTy_Mul:
+        case PoTy_Div:
+        case PoTy_Mod: {
+            EvaledOperand left = eval_operand_to_imm(evaluator, operand->left);
+            if (left.ty == EoTy_Err) {
+                return left;
+            } else if (left.ty != EoTy_Imm) {
+                REPORTF_ERROR("%s", "operand cannot be used in expressions");
+                reporter_print_loc(evaluator->rep, operand->left->loc);
+                return (EvaledOperand) { .ty = EoTy_Err };
+            }
+            EvaledOperand right
+                = eval_operand_to_imm(evaluator, operand->right);
+            if (right.ty == EoTy_Err) {
+                return right;
+            } else if (right.ty != EoTy_Imm) {
+                REPORTF_ERROR("%s", "operand cannot be used in expressions");
+                reporter_print_loc(evaluator->rep, operand->right->loc);
+                return (EvaledOperand) { .ty = EoTy_Err };
+            }
+            return (EvaledOperand) {
+                .ty = EoTy_Imm,
+                .imm = eval_poperandty_binary(operand->ty, left.imm, right.imm),
+            };
+        }
+    }
+    fprintf(stderr, "unreachable\n");
+    exit(1);
+}
+
+EvaledOperand eval_operand_indirection_expr(
+    OperandEvaluator* evaluator, POperand* operand)
+{
+    switch (operand->ty) {
+        case PoTy_Reg:
+            return (EvaledOperand) {
+                .ty = EoTy_Mem8Reg,
+                .reg = operand->reg,
+                .offset = 0,
+            };
+        case PoTy_Str:
+            REPORTF_ERROR("%s", "strings cannot be part of indirections");
+            reporter_print_loc(evaluator->rep, operand->loc);
+            return (EvaledOperand) { .ty = EoTy_Err };
+        case PoTy_Mem8:
+        case PoTy_Mem16:
+            REPORTF_ERROR("%s", "indirections cannot be part of indirections");
+            reporter_print_loc(evaluator->rep, operand->loc);
+            return (EvaledOperand) { .ty = EoTy_Err };
+        case PoTy_Imm:
+        case PoTy_Ident:
+        case PoTy_SubLabel:
+        case PoTy_Not:
+        case PoTy_Negate:
+        case PoTy_Or:
+        case PoTy_Xor:
+        case PoTy_And:
+        case PoTy_Shl:
+        case PoTy_Shr:
+        case PoTy_Mul:
+        case PoTy_Div:
+        case PoTy_Mod: {
+            EvaledOperand evaled = eval_operand_to_imm(evaluator, operand);
+            if (evaled.ty == EoTy_Err) {
+                return evaled;
+            }
+            return (EvaledOperand) {
+                .ty = EoTy_Mem8Imm,
+                .imm = evaled.imm,
+            };
+        }
+        case PoTy_Add: {
+            if (operand->left->ty == PoTy_Reg) {
+                EvaledOperand right
+                    = eval_operand_to_imm(evaluator, operand->right);
+                if (right.ty == EoTy_Err) {
+                    return right;
+                }
+                return (EvaledOperand) {
+                    .ty = EoTy_Mem8Imm,
+                    .reg = operand->left->reg,
+                    .offset = right.imm,
+                };
+            } else if (operand->right->ty == PoTy_Reg) {
+                EvaledOperand left
+                    = eval_operand_to_imm(evaluator, operand->left);
+                if (left.ty == EoTy_Err) {
+                    return left;
+                }
+                return (EvaledOperand) {
+                    .ty = EoTy_Mem8Imm,
+                    .reg = operand->right->reg,
+                    .offset = left.imm,
+                };
+            } else {
+                EvaledOperand evaled = eval_operand_to_imm(evaluator, operand);
+                if (evaled.ty == EoTy_Err) {
+                    return evaled;
+                }
+                return (EvaledOperand) {
+                    .ty = EoTy_Mem8Imm,
+                    .imm = evaled.imm,
+                };
+            }
+            break;
+        }
+        case PoTy_Sub: {
+            if (operand->left->ty == PoTy_Reg) {
+                EvaledOperand right
+                    = eval_operand_to_imm(evaluator, operand->right);
+                if (right.ty == EoTy_Err) {
+                    return right;
+                }
+                return (EvaledOperand) {
+                    .ty = EoTy_Mem8Imm,
+                    .reg = operand->left->reg,
+                    .offset = (uint16_t)-(int16_t)right.imm,
+                };
+            } else if (operand->right->ty == PoTy_Reg) {
+                EvaledOperand left
+                    = eval_operand_to_imm(evaluator, operand->left);
+                if (left.ty == EoTy_Err) {
+                    return left;
+                }
+                return (EvaledOperand) {
+                    .ty = EoTy_Mem8Imm,
+                    .reg = operand->right->reg,
+                    .offset = (uint16_t)-(int16_t)left.imm,
+                };
+            } else {
+                EvaledOperand evaled = eval_operand_to_imm(evaluator, operand);
+                if (evaled.ty == EoTy_Err) {
+                    return evaled;
+                }
+                return (EvaledOperand) {
+                    .ty = EoTy_Mem8Imm,
+                    .imm = evaled.imm,
+                };
+            }
+            break;
+        }
+    }
+    fprintf(stderr, "unreachable\n");
+    exit(1);
+}
+
+EvaledOperand eval_operand(OperandEvaluator* evaluator, POperand* operand)
+{
+    switch (operand->ty) {
+        case PoTy_Str:
+            return (EvaledOperand) { .ty = EoTy_Str };
+        case PoTy_Mem8:
+            return eval_operand_indirection_expr(evaluator, operand->operand);
+        case PoTy_Mem16: {
+            EvaledOperand evaled
+                = eval_operand_indirection_expr(evaluator, operand->operand);
+            switch (evaled.ty) {
+                case EoTy_Mem8Reg:
+                    evaled.ty = EoTy_MemU16Reg;
+                    break;
+                case EoTy_Mem8Imm:
+                    evaled.ty = EoTy_MemU16Imm;
+                    break;
+                default:
+                    break;
+            }
+            return evaled;
+        }
+        case PoTy_Reg:
+            return (EvaledOperand) { .ty = EoTy_Reg, .reg = operand->reg };
+        case PoTy_Imm:
+        case PoTy_Ident:
+        case PoTy_SubLabel:
+        case PoTy_Not:
+        case PoTy_Negate:
+        case PoTy_Or:
+        case PoTy_Xor:
+        case PoTy_And:
+        case PoTy_Shl:
+        case PoTy_Shr:
+        case PoTy_Add:
+        case PoTy_Sub:
+        case PoTy_Mul:
+        case PoTy_Div:
+        case PoTy_Mod:
+            return eval_operand_to_imm(evaluator, operand);
+    }
+    fprintf(stderr, "unreachable\n");
+    exit(1);
+}

asm/eval.h

@@ -0,0 +1,39 @@
+#pragma once
+
+#include "common/arch.h"
+#include "parse.h"
+#include "resolve.h"
+#include <stdbool.h>
+#include <stdint.h>
+
+typedef enum {
+    EoTy_Err,
+    EoTy_Reg,
+    EoTy_Imm,
+    EoTy_Str,
+    EoTy_Mem8Reg,
+    EoTy_Mem8Imm,
+    EoTy_MemU16Reg,
+    EoTy_MemU16Imm,
+} EvaledOperandTy;
+
+typedef struct {
+    EvaledOperandTy ty;
+    union {
+        Reg reg;
+        uint16_t imm;
+    };
+    uint16_t offset;
+} EvaledOperand;
+
+typedef struct {
+    IdentResolver* re;
+    Reporter* rep;
+    bool second_pass;
+} OperandEvaluator;
+
+EvaledOperand eval_operand_to_imm(
+    OperandEvaluator* evaluator, POperand* operand);
+EvaledOperand eval_operand_indirection_expr(
+    OperandEvaluator* evaluator, POperand* operand);
+EvaledOperand eval_operand(OperandEvaluator* evaluator, POperand* operand);

asm/lex.c

@@ -0,0 +1,178 @@
+#include "lex.h"
+#include "report.h"
+#include "str.h"
+#include <string.h>
+
+void lexer_construct(Lexer* lexer, const char* filename, const char* text)
+{
+    *lexer = (Lexer) {
+        .filename = filename,
+        .text = text,
+        .text_len = strlen(text),
+        .idx = 0,
+        .line = 1,
+        .col = 1,
+        .ch = text[0],
+        .error_occured = false,
+    };
+}
+
+static inline bool lexer_done(const Lexer* lexer)
+{
+    return lexer->idx >= lexer->text_len;
+}
+
+static inline void lexer_step(Lexer* lexer)
+{
+    if (lexer_done(lexer)) {
+        return;
+    }
+    if (lexer->ch == '\n') {
+        lexer->line += 1;
+        lexer->col = 1;
+    } else {
+        lexer->col += 1;
+    }
+    lexer->idx += 1;
+    lexer->ch = lexer->text[lexer->idx];
+}
+
+static inline Loc lexer_loc(const Lexer* lexer)
+{
+    return (Loc) { .idx = lexer->idx, .line = lexer->line, .col = lexer->col };
+}
+
+static inline Tok lexer_tok(const Lexer* lexer, TokTy ty, Loc loc)
+{
+    return (Tok) { .ty = ty, .loc = loc, .len = lexer->idx - loc.idx };
+}
+
+static inline int lexer_skip_literal_char(Lexer* lexer)
+{
+    char ch = lexer->ch;
+    lexer_step(lexer);
+    if (ch == '\\') {
+        if (lexer_done(lexer))
+            return -1;
+        lexer_step(lexer);
+    }
+    return 0;
+}
+
+static inline void lexer_report(Lexer* lexer, const char* msg, Loc loc)
+{
+    lexer->error_occured = true;
+    REPORTF_ERROR("%s", msg);
+    print_report_loc(lexer->filename, lexer->text, lexer->text_len, loc);
+}
+
+Tok lexer_next(Lexer* lexer)
+{
+    const char* ident_chars = "abcdefghijklmnopqrstuvwxyz"
+                              "ABCDEFGHIJKLMNOPQRSTUVWXYZ_$";
+    const char* int_chars = "1234567890";
+    const char* hex_chars = "01234567889abcdefABCDEF";
+
+    Loc loc = lexer_loc(lexer);
+    if (lexer_done(lexer)) {
+        return lexer_tok(lexer, TT_Eof, loc);
+    }
+    if (lexer->ch == '\n') {
+        lexer_step(lexer);
+        return lexer_tok(lexer, '\n', loc);
+    } else if (str_includes(" \t", lexer->ch)) {
+        while (!lexer_done(lexer) && str_includes(" \t", lexer->ch)) {
+            lexer_step(lexer);
+        }
+        return lexer_next(lexer);
+    } else if (str_includes(ident_chars, lexer->ch)) {
+        while (!lexer_done(lexer)
+            && (str_includes(ident_chars, lexer->ch)
+                || str_includes(int_chars, lexer->ch))) {
+            lexer_step(lexer);
+        }
+        return lexer_tok(lexer, TT_Ident, loc);
+    } else if (str_includes(int_chars, lexer->ch) && lexer->ch != '0') {
+        while (!lexer_done(lexer) && (str_includes(int_chars, lexer->ch))) {
+            lexer_step(lexer);
+        }
+        return lexer_tok(lexer, TT_Int, loc);
+    } else if (lexer->ch == ';') {
+        while (!lexer_done(lexer) && lexer->ch != '\n') {
+            lexer_step(lexer);
+        }
+        return lexer_next(lexer);
+    } else if (lexer->ch == '0') {
+        lexer_step(lexer);
+        if (lexer->ch == 'b') {
+            lexer_step(lexer);
+            if (lexer_done(lexer) || !str_includes("01", lexer->ch)) {
+                lexer_report(lexer, "malformed binary literal", loc);
+                return lexer_tok(lexer, TT_Err, loc);
+            }
+            while (!lexer_done(lexer) && str_includes("01", lexer->ch)) {
+                lexer_step(lexer);
+            }
+            return lexer_tok(lexer, TT_Binary, loc);
+        } else if (lexer->ch == 'x') {
+            lexer_step(lexer);
+            if (lexer_done(lexer) || !str_includes(hex_chars, lexer->ch)) {
+                lexer_report(lexer, "malformed hex literal", loc);
+                return lexer_tok(lexer, TT_Err, loc);
+            }
+            while (!lexer_done(lexer) && str_includes(hex_chars, lexer->ch)) {
+                lexer_step(lexer);
+            }
+            return lexer_tok(lexer, TT_Hex, loc);
+
+        } else {
+            return lexer_tok(lexer, TT_Int, loc);
+        }
+    } else if (lexer->ch == '\'') {
+        lexer_step(lexer);
+        lexer_skip_literal_char(lexer);
+        if (lexer_done(lexer) || lexer->ch != '\'') {
+            lexer_report(lexer, "malformed character literal", loc);
+            return lexer_tok(lexer, TT_Err, loc);
+        }
+        lexer_step(lexer);
+        return lexer_tok(lexer, TT_Char, loc);
+    } else if (lexer->ch == '"') {
+        lexer_step(lexer);
+        while (!lexer_done(lexer) && lexer->ch != '"') {
+            lexer_skip_literal_char(lexer);
+        }
+        if (lexer_done(lexer) || lexer->ch != '"') {
+            lexer_report(lexer, "malformed string literal", loc);
+            return lexer_tok(lexer, TT_Err, loc);
+        }
+        lexer_step(lexer);
+        return lexer_tok(lexer, TT_Str, loc);
+    } else if (lexer->ch == '<') {
+        lexer_step(lexer);
+        if (!lexer_done(lexer) && lexer->ch == '<') {
+            lexer_step(lexer);
+            return lexer_tok(lexer, TT_DoubleLt, loc);
+        } else {
+            lexer_report(lexer, "expected '<'", loc);
+            return lexer_tok(lexer, TT_Err, loc);
+        }
+    } else if (lexer->ch == '>') {
+        lexer_step(lexer);
+        if (!lexer_done(lexer) && lexer->ch == '>') {
+            lexer_step(lexer);
+            return lexer_tok(lexer, TT_DoubleGt, loc);
+        } else {
+            lexer_report(lexer, "expected '>'", loc);
+            return lexer_tok(lexer, TT_Err, loc);
+        }
+    } else if (str_includes("|^&+-*/%()[].,:!", lexer->ch)) {
+        char ch = lexer->ch;
+        lexer_step(lexer);
+        return lexer_tok(lexer, (TokTy)ch, loc);
+    } else {
+        lexer_report(lexer, "illegal character", loc);
+        lexer_step(lexer);
+        return lexer_tok(lexer, TT_Err, loc);
+    }
+}

asm/lex.h

@@ -0,0 +1,55 @@
+#pragma once
+
+#include "report.h"
+#include <stdbool.h>
+#include <stddef.h>
+
+typedef enum {
+    TT_Err,
+    TT_Eof,
+    TT_Ident,
+    TT_Int,
+    TT_Binary,
+    TT_Hex,
+    TT_Char,
+    TT_Str,
+    TT_Newline = '\n',
+    TT_DoubleLt,
+    TT_DoubleGt,
+    TT_Pipe = '|',
+    TT_Hat = '^',
+    TT_Ampersand = '&',
+    TT_Plus = '+',
+    TT_Minus = '-',
+    TT_Asterisk = '*',
+    TT_Slash = '/',
+    TT_Percent = '%',
+    TT_LParen = '(',
+    TT_RParen = ')',
+    TT_LBracket = '[',
+    TT_RBracket = ']',
+    TT_Dot = '.',
+    TT_Comma = ',',
+    TT_Colon = ':',
+    TT_Exclamation = '!',
+} TokTy;
+
+typedef struct {
+    TokTy ty;
+    Loc loc;
+    size_t len;
+} Tok;
+
+typedef struct {
+    const char* filename;
+    const char* text;
+    size_t text_len;
+    size_t idx;
+    int line;
+    int col;
+    char ch;
+    bool error_occured;
+} Lexer;
+
+void lexer_construct(Lexer* lexer, const char* filename, const char* text);
+Tok lexer_next(Lexer* lexer);

asm/parse.c

@@ -0,0 +1,534 @@
+#include "parse.h"
+#include "lex.h"
+#include "report.h"
+#include "str.h"
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+PLabel* plabel_new(PLabel* next, char* ident, bool sub_label, Loc loc)
+{
+    PLabel* label = malloc(sizeof(PLabel));
+    *label = (PLabel) { next, ident, loc, sub_label };
+    return label;
+}
+
+void plabel_free(PLabel* label)
+{
+    if (!label) {
+        return;
+    }
+    plabel_free(label->next);
+    free(label->ident);
+    free(label);
+}
+
+POperand* poperand_new_reg(Reg reg, Loc loc)
+{
+    POperand* operand = malloc(sizeof(POperand));
+    *operand = (POperand) { .ty = PoTy_Reg, .loc = loc, .reg = reg };
+    return operand;
+}
+
+POperand* poperand_new_imm(uint16_t imm, Loc loc)
+{
+    POperand* operand = malloc(sizeof(POperand));
+    *operand = (POperand) { .ty = PoTy_Imm, .loc = loc, .imm = imm };
+    return operand;
+}
+
+POperand* poperand_new_str(POperandTy ty, char* str, size_t str_len, Loc loc)
+{
+    POperand* operand = malloc(sizeof(POperand));
+    *operand = (POperand) {
+        .ty = ty,
+        .loc = loc,
+        .str = str,
+        .str_len = str_len,
+    };
+    return operand;
+}
+
+POperand* poperand_new_unary(POperandTy ty, POperand* inner, Loc loc)
+{
+    POperand* operand = malloc(sizeof(POperand));
+    *operand = (POperand) { .ty = ty, .loc = loc, .operand = inner };
+    return operand;
+}
+
+POperand* poperand_new_binary(
+    POperandTy ty, POperand* left, POperand* right, Loc loc)
+{
+    POperand* operand = malloc(sizeof(POperand));
+    *operand
+        = (POperand) { .ty = ty, .loc = loc, .left = left, .right = right };
+    return operand;
+}
+
+void poperand_free(POperand* operand)
+{
+    switch (operand->ty) {
+        case PoTy_Reg:
+        case PoTy_Imm:
+            break;
+        case PoTy_Ident:
+        case PoTy_SubLabel:
+        case PoTy_Str:
+            free(operand->str);
+            break;
+        case PoTy_Mem8:
+        case PoTy_Mem16:
+        case PoTy_Not:
+        case PoTy_Negate:
+            poperand_free(operand->operand);
+            break;
+        case PoTy_Or:
+        case PoTy_Xor:
+        case PoTy_And:
+        case PoTy_Shl:
+        case PoTy_Shr:
+        case PoTy_Add:
+        case PoTy_Sub:
+        case PoTy_Mul:
+        case PoTy_Div:
+        case PoTy_Mod:
+            poperand_free(operand->left);
+            poperand_free(operand->right);
+            break;
+    }
+    free(operand);
+}
+
+PLine* pline_new(
+    char* op, PLabel* labels, Loc loc, size_t ops_size, POperand** ops)
+{
+    PLine* line = malloc(sizeof(PLine) + sizeof(POperand*) * ops_size);
+    *line = (PLine) {
+        .labels = labels,
+        .op = op,
+        .loc = loc,
+        .ops_size = ops_size,
+    };
+    for (size_t i = 0; i < ops_size; ++i) {
+        line->ops[i] = ops[i];
+    }
+    return line;
+}
+
+void pline_free(PLine* pline)
+{
+    plabel_free(pline->labels);
+    free(pline->op);
+    for (size_t i = 0; i < pline->ops_size; ++i) {
+        poperand_free(pline->ops[i]);
+    }
+    free(pline);
+}
+
+void pstmt_free(PStmt* stmt)
+{
+    switch (stmt->ty) {
+        case PStmtTy_Line:
+            pline_free(stmt->line);
+            break;
+        case PStmtTy_Global:
+        case PStmtTy_Extern:
+        case PStmtTy_Define:
+            free(stmt->ident);
+            break;
+    }
+    free(stmt);
+}
+
+void parser_construct(Parser* parser, const char* filename, const char* text)
+{
+    Lexer lexer;
+    lexer_construct(&lexer, filename, text);
+
+    *parser = (Parser) {
+        .lexer = lexer,
+        .tok = lexer_next(&lexer),
+        .eaten = (Tok) { 0 },
+        .error_occured = false,
+    };
+}
+
+bool parser_done(const Parser* parser)
+{
+    return parser->tok.ty == TT_Eof;
+}
+
+bool parser_error_occured(const Parser* parser)
+{
+    return parser->error_occured || parser->lexer.error_occured;
+}
+
+static inline void parser_step(Parser* parser)
+{
+    parser->tok = lexer_next(&parser->lexer);
+}
+
+static inline bool parser_test(const Parser* parser, TokTy ty)
+{
+    return parser->tok.ty == ty;
+}
+
+static inline bool parser_eat(Parser* parser, TokTy ty)
+{
+    if (parser_test(parser, ty)) {
+        parser->eaten = parser->tok;
+        parser_step(parser);
+        return true;
+    }
+    return false;
+}
+
+static inline char* parser_ident_val(const Parser* parser, Tok tok)
+{
+    return asm_strndup(&parser->lexer.text[tok.loc.idx], tok.len);
+}
+
+static inline void parser_report(Parser* parser, const char* msg, Loc loc)
+{
+    parser->error_occured = true;
+    REPORTF_ERROR("%s", msg);
+    print_report_loc(parser->lexer.filename,
+        parser->lexer.text,
+        parser->lexer.text_len,
+        loc);
+}
+
+static inline void parser_skip_newlines(Parser* parser)
+{
+    while (parser_eat(parser, '\n')) { }
+}
+
+static inline PLabel* parser_parse_labels(
+    Parser* parser, char** ident, Loc* ident_loc)
+{
+    *ident = NULL;
+    PLabel* labels = NULL;
+    while (parser->tok.ty != TT_Eof && *ident == NULL) {
+        parser_skip_newlines(parser);
+        Loc loc = parser->tok.loc;
+        if (parser_eat(parser, '.')) {
+            if (!parser_eat(parser, TT_Ident)) {
+                parser_report(parser, "expected identifier", parser->tok.loc);
+                plabel_free(labels);
+                return NULL;
+            }
+            char* label_ident = parser_ident_val(parser, parser->eaten);
+            if (!parser_eat(parser, ':')) {
+                parser_report(parser, "expected ':'", parser->tok.loc);
+                plabel_free(labels);
+                free(label_ident);
+                return NULL;
+            }
+            labels = plabel_new(labels, label_ident, true, loc);
+        } else if (parser_eat(parser, TT_Ident)) {
+            *ident = parser_ident_val(parser, parser->eaten);
+            *ident_loc = loc;
+            if (!parser_eat(parser, ':')) {
+                break;
+            }
+            labels = plabel_new(labels, *ident, false, loc);
+            *ident = NULL;
+        } else {
+            parser_report(
+                parser, "expected identifier or ':'", parser->tok.loc);
+            plabel_free(labels);
+            return NULL;
+        }
+    }
+    return labels;
+}
+
+static inline char literal_char_val(const char* str)
+{
+    if (str[0] == '\\') {
+        switch (str[1]) {
+            case '0':
+                return 0;
+            case 't':
+                return '\t';
+            case 'n':
+                return '\n';
+            default:
+                return str[1];
+        }
+    } else {
+        return str[0];
+    }
+}
+
+static const int parser_binary_prec = 6;
+static inline POperand* parser_parse_operand_2(Parser* parser, int prec);
+
+static inline POperand* parser_parse_operand_0(Parser* parser)
+{
+    Loc loc = parser->tok.loc;
+    if (parser_eat(parser, TT_Ident)) {
+        char* ident = parser_ident_val(parser, parser->eaten);
+        const char* reg_key[10] = {
+            "r0", "r1", "r2", "r3", "r4", "rbp", "rsp", "rfl", "rcs", "rip"
+        };
+        Reg reg_val[10] = { R0, R1, R2, R3, R4, Rbp, Rsp, Rfl, Rcs, Rip };
+        for (size_t i = 0; i < 10; ++i) {
+            if (strcmp(reg_key[i], ident) == 0) {
+                free(ident);
+                return poperand_new_reg(reg_val[i], loc);
+            }
+        }
+        return poperand_new_str(PoTy_Ident, ident, parser->eaten.len, loc);
+    } else if (parser_eat(parser, TT_Int)) {
+        char* str = parser_ident_val(parser, parser->eaten);
+        uint64_t val = strtoull(str, NULL, 10);
+        free(str);
+        if (val > 0xffff) {
+            parser_report(parser,
+                "integers larger than 65536 not supported",
+                parser->tok.loc);
+            return NULL;
+        }
+        uint16_t imm = (uint16_t)val;
+        return poperand_new_imm(imm, loc);
+    } else if (parser_eat(parser, TT_Binary)) {
+        char* str = parser_ident_val(parser, parser->eaten);
+        uint64_t val = strtoull(&str[2], NULL, 2);
+        free(str);
+        if (val > 0xffff) {
+            parser_report(parser,
+                "integers larger than 65536 not supported",
+                parser->tok.loc);
+            return NULL;
+        }
+        uint16_t imm = (uint16_t)val;
+        return poperand_new_imm(imm, loc);
+    } else if (parser_eat(parser, TT_Hex)) {
+        char* str = parser_ident_val(parser, parser->eaten);
+        uint64_t val = strtoull(&str[2], NULL, 16);
+        free(str);
+        if (val > 0xffff) {
+            parser_report(parser,
+                "integers larger than 65536 not supported",
+                parser->tok.loc);
+            return NULL;
+        }
+        uint16_t imm = (uint16_t)val;
+        return poperand_new_imm(imm, loc);
+    } else if (parser_eat(parser, TT_Char)) {
+        char* str = parser_ident_val(parser, parser->eaten);
+        uint16_t imm = (uint16_t)literal_char_val(&str[1]);
+        free(str);
+        return poperand_new_imm(imm, loc);
+    } else if (parser_eat(parser, TT_Str)) {
+        char* lit = parser_ident_val(parser, parser->eaten);
+        size_t lit_len = strlen(lit);
+        char* str = calloc(lit_len - 1, sizeof(char));
+        size_t str_len = 0;
+        for (size_t i = 1; i < lit_len - 2; ++i) {
+            str[i] = literal_char_val(&lit[i]);
+        }
+        free(lit);
+        return poperand_new_str(PoTy_Str, str, str_len, loc);
+    } else if (parser_eat(parser, '.')) {
+        if (!parser_eat(parser, TT_Ident)) {
+            parser_report(parser, "expected identifier", parser->tok.loc);
+            return NULL;
+        }
+        char* ident = parser_ident_val(parser, parser->eaten);
+        return poperand_new_str(PoTy_SubLabel, ident, parser->eaten.len, loc);
+    } else if (parser_eat(parser, '(')) {
+        POperand* operand = parser_parse_operand_2(parser, parser_binary_prec);
+        if (!parser_eat(parser, ')')) {
+            parser_report(parser, "expected ')'", parser->tok.loc);
+            poperand_free(operand);
+            return NULL;
+        }
+        return operand;
+    } else {
+        parser_report(parser, "expected operand", parser->tok.loc);
+        return NULL;
+    }
+}
+
+static inline POperand* parser_parse_operand_1(Parser* parser)
+{
+
+    Loc loc = parser->tok.loc;
+    if (parser_eat(parser, '-')) {
+        POperand* operand = parser_parse_operand_1(parser);
+        return poperand_new_unary(PoTy_Negate, operand, loc);
+    } else if (parser_eat(parser, '!')) {
+        POperand* operand = parser_parse_operand_1(parser);
+        return poperand_new_unary(PoTy_Not, operand, loc);
+    } else {
+        return parser_parse_operand_0(parser);
+    }
+}
+
+static inline POperand* parser_parse_operand_2(Parser* parser, int prec)
+{
+    const POperandTy op_tys[] = {
+        PoTy_Or,
+        PoTy_Xor,
+        PoTy_And,
+        PoTy_Shr,
+        PoTy_Shl,
+        PoTy_Add,
+        PoTy_Sub,
+        PoTy_Mul,
+        PoTy_Div,
+        PoTy_Mod,
+    };
+    const TokTy op_tts[] = {
+        '|',
+        '^',
+        '&',
+        TT_DoubleGt,
+        TT_DoubleLt,
+        '+',
+        '-',
+        '*',
+        '/',
+        '%',
+    };
+    const int op_precs[] = { 6, 5, 4, 3, 3, 2, 2, 1, 1, 1 };
+    static_assert(sizeof(op_tys) / sizeof(op_tys[0])
+            == sizeof(op_tts) / sizeof(op_tts[0]),
+        "misaligned");
+    static_assert(sizeof(op_tys) / sizeof(op_tys[0])
+            == sizeof(op_precs) / sizeof(op_precs[0]),
+        "misaligned");
+
+    if (prec == 0) {
+        return parser_parse_operand_1(parser);
+    }
+    POperand* left = parser_parse_operand_2(parser, prec - 1);
+    bool should_continue = true;
+    while (should_continue) {
+        should_continue = false;
+        for (size_t i = 0; i < sizeof(op_tys) / sizeof(op_tys[0]); ++i) {
+            if (prec >= op_precs[i] && parser_eat(parser, op_tts[i])) {
+                POperand* right = parser_parse_operand_2(parser, prec - 1);
+                left = poperand_new_binary(op_tys[i], left, right, left->loc);
+                should_continue = true;
+                break;
+            }
+        }
+    }
+    return left;
+}
+
+static inline POperand* parser_parse_operand_3(Parser* parser)
+{
+    Loc loc = parser->tok.loc;
+    if (parser_eat(parser, TT_LBracket)) {
+        parser_report(parser, "expected 'u8' or 'u16' before '['", loc);
+        return NULL;
+    }
+    if (!parser_test(parser, TT_Ident)) {
+        return parser_parse_operand_2(parser, parser_binary_prec);
+    }
+    char* ident = parser_ident_val(parser, parser->tok);
+    if (strcmp(ident, "u8") == 0) {
+        free(ident);
+        parser_step(parser);
+        if (!parser_eat(parser, '[')) {
+            parser_report(parser, "expected '['", parser->tok.loc);
+            return NULL;
+        }
+        POperand* operand = parser_parse_operand_2(parser, parser_binary_prec);
+        if (!parser_eat(parser, ']')) {
+            parser_report(parser, "expected ']'", parser->tok.loc);
+            poperand_free(operand);
+            return NULL;
+        }
+        return poperand_new_unary(PoTy_Mem8, operand, loc);
+    } else if (strcmp(ident, "u16") == 0) {
+        free(ident);
+        parser_step(parser);
+        if (!parser_eat(parser, '[')) {
+            parser_report(parser, "expected '['", parser->tok.loc);
+            return NULL;
+        }
+        POperand* operand = parser_parse_operand_2(parser, parser_binary_prec);
+        if (!parser_eat(parser, ']')) {
+            parser_report(parser, "expected ']'", parser->tok.loc);
+            poperand_free(operand);
+            return NULL;
+        }
+        return poperand_new_unary(PoTy_Mem16, operand, loc);
+    } else {
+        free(ident);
+        return parser_parse_operand_2(parser, parser_binary_prec);
+    }
+}
+
+static inline void parser_skip_to_next_line(Parser* parser)
+{
+    while (!parser_done(parser) && !parser_eat(parser, TT_Newline)) {
+        parser_step(parser);
+    }
+}
+
+PLine* parser_next(Parser* parser)
+{
+    char* ident;
+    Loc loc;
+    PLabel* labels = parser_parse_labels(parser, &ident, &loc);
+
+    const size_t max_ops_size = 64;
+    // TODO: Move allocation out-of-band.
+    POperand** ops = malloc(sizeof(POperand) * max_ops_size);
+    size_t ops_size = 0;
+
+    if (!parser_test(parser, TT_Eof) && !parser_test(parser, '\n')) {
+        POperand* operand = parser_parse_operand_3(parser);
+        if (!operand) {
+            parser_skip_to_next_line(parser);
+            goto error_free_ops;
+        }
+        ops[ops_size++] = operand;
+        while (!parser_test(parser, TT_Eof) && !parser_test(parser, '\n')
+            && ops_size < 3) {
+            if (ops_size >= max_ops_size) {
+                parser_report(parser,
+                    "exceeded maximum number of operands (64)",
+                    parser->tok.loc);
+                parser_skip_to_next_line(parser);
+                goto error_free_ops;
+            }
+            if (!parser_eat(parser, ',')) {
+                parser_report(parser, "expected ','", parser->tok.loc);
+                parser_skip_to_next_line(parser);
+                goto error_free_ops;
+            }
+            POperand* operand = parser_parse_operand_3(parser);
+            if (!operand) {
+                parser_skip_to_next_line(parser);
+                goto error_free_ops;
+            }
+            ops[ops_size++] = operand;
+        }
+    }
+    if (!parser_eat(parser, '\n') && !parser_test(parser, TT_Eof)) {
+        parser_report(parser, "expected newline", parser->tok.loc);
+        goto error_free_ops;
+    }
+    parser_skip_newlines(parser);
+
+    PLine* line = pline_new(ident, labels, loc, ops_size, ops);
+    free(ops);
+    return line;
+
+error_free_ops:
+    for (size_t i = 0; i < ops_size; ++i)
+        if (ops[i])
+            poperand_free(ops[i]);
+    free(ops);
+    plabel_free(labels);
+    free(ident);
+    return NULL;
+}

asm/parse.h

@@ -0,0 +1,110 @@
+#pragma once
+
+#include "common/arch.h"
+#include "lex.h"
+#include "report.h"
+#include <stdbool.h>
+#include <stdint.h>
+
+typedef struct PLabel PLabel;
+
+struct PLabel {
+    PLabel* next;
+    char* ident;
+    Loc loc;
+    bool sub_label;
+};
+
+PLabel* plabel_new(PLabel* next, char* ident, bool sub_label, Loc loc);
+void plabel_free(PLabel* label);
+
+typedef enum {
+    PoTy_Reg,
+    PoTy_Imm,
+    PoTy_Ident,
+    PoTy_SubLabel,
+    PoTy_Str,
+    PoTy_Mem8,
+    PoTy_Mem16,
+    PoTy_Not,
+    PoTy_Negate,
+    PoTy_Or,
+    PoTy_Xor,
+    PoTy_And,
+    PoTy_Shl,
+    PoTy_Shr,
+    PoTy_Add,
+    PoTy_Sub,
+    PoTy_Mul,
+    PoTy_Div,
+    PoTy_Mod,
+} POperandTy;
+
+typedef struct POperand POperand;
+
+struct POperand {
+    POperandTy ty;
+    Loc loc;
+    union {
+        Reg reg;
+        uint16_t imm;
+        struct {
+            char* str;
+            size_t str_len;
+        };
+        POperand* operand;
+        struct {
+            POperand* left;
+            POperand* right;
+        };
+    };
+};
+
+POperand* poperand_new_reg(Reg reg, Loc loc);
+POperand* poperand_new_imm(uint16_t imm, Loc loc);
+POperand* poperand_new_str(POperandTy ty, char* str, size_t str_len, Loc loc);
+POperand* poperand_new_unary(POperandTy ty, POperand* inner, Loc loc);
+POperand* poperand_new_binary(
+    POperandTy ty, POperand* left, POperand* right, Loc loc);
+void poperand_free(POperand* operand);
+
+typedef struct {
+    PLabel* labels;
+    char* op;
+    Loc loc;
+    size_t ops_size;
+    POperand* ops[];
+} PLine;
+
+PLine* pline_new(
+    char* op, PLabel* labels, Loc loc, size_t ops_size, POperand** ops);
+void pline_free(PLine* pline);
+
+typedef enum {
+    PStmtTy_Line,
+    PStmtTy_Global,
+    PStmtTy_Extern,
+    PStmtTy_Define,
+} PStmtTy;
+
+typedef struct {
+    PStmtTy ty;
+    union {
+        PLine* line;
+        char* ident;
+    };
+} PStmt;
+
+void pstmt_free(PStmt* stmt);
+
+typedef struct {
+    Lexer lexer;
+    Tok tok;
+    Tok eaten;
+    bool error_occured;
+} Parser;
+
+void parser_construct(Parser* parser, const char* filename, const char* text);
+bool parser_done(const Parser* parser);
+bool parser_error_occured(const Parser* parser);
+PLine* parser_next(Parser* parser);

asm/report.c

@@ -0,0 +1,44 @@
+#include "report.h"
+#include <stdio.h>
+
+void print_report_loc(
+    const char* filename, const char* text, size_t text_len, Loc loc)
+{
+    size_t line_start = loc.idx;
+    while (line_start > 0 && text[line_start] != '\n') {
+        line_start -= 1;
+    }
+    if (text[line_start] == '\n') {
+        line_start += 1;
+    }
+    size_t line_end = loc.idx + 1;
+    while (line_end < text_len && text[line_end] != '\n') {
+        line_end += 1;
+    }
+    const char* line = &text[line_start];
+    int line_len = (int)line_end - (int)line_start;
+
+    fprintf(stderr,
+        "    \x1b[96m--> ./%s:%d:%d\n     "
+        "\x1b[37m|\n\x1b[96m%5d\x1b[37m|%.*s\n     "
+        "|%*c\x1b[1;91m^\x1b[0m\n",
+        filename,
+        loc.line,
+        loc.col,
+        loc.line,
+        line_len,
+        line,
+        loc.col - 1,
+        ' ');
+}
+
+void reporter_print_loc(Reporter* rep, Loc loc)
+{
+    print_report_loc(rep->filename, rep->text, rep->text_len, loc);
+}
+
+void reporter_error_with_loc(Reporter* rep, const char* msg, Loc loc)
+{
+    REPORTF_ERROR("%s", msg);
+    reporter_print_loc(rep, loc);
+}

asm/report.h

@@ -0,0 +1,31 @@
+#pragma once
+
+#include <stddef.h>
+#include <stdio.h>
+
+typedef struct {
+    size_t idx;
+    int line;
+    int col;
+} Loc;
+
+#define REPORTF_ERROR(FMT, ...)                                                \
+    (fprintf(                                                                  \
+        stderr, "\x1b[1;91merror\x1b[1;97m: " FMT "\x1b[0m\n", __VA_ARGS__))
+#define REPORTF_INFO(FMT, ...)                                                 \
+    (fprintf(stderr, "\x1b[1;96minfo\x1b[1;97m: " FMT "\x1b[0m\n", __VA_ARGS__))
+#define REPORTF_WARNING(FMT, ...)                                              \
+    (fprintf(                                                                  \
+        stderr, "\x1b[1;93mwarning\x1b[1;97m: " FMT "\x1b[0m\n", __VA_ARGS__))
+
+void print_report_loc(
+    const char* filename, const char* text, size_t text_len, Loc loc);
+
+typedef struct {
+    const char* filename;
+    const char* text;
+    size_t text_len;
+} Reporter;
+
+void reporter_print_loc(Reporter* rep, Loc loc);
+void reporter_error_with_loc(Reporter* rep, const char* msg, Loc loc);

asm/resolve.c

@@ -0,0 +1,92 @@
+#include "resolve.h"
+#include <stdlib.h>
+#include <string.h>
+
+void ident_resol_destroy(IdentResol* resol)
+{
+    switch (resol->ty) {
+        case IdentResolTy_None:
+            break;
+        case IdentResolTy_Label:
+        case IdentResolTy_SubLabel:
+            free(resol->ident);
+            break;
+    }
+}
+
+void ident_resolver_construct(IdentResolver* resolver)
+{
+    size_t capacity = 512;
+    *resolver = (IdentResolver) {
+        .resols = malloc(sizeof(IdentResol) * capacity),
+        .resols_capacity = capacity,
+        .resols_size = 0,
+    };
+}
+
+void ident_resolver_destroy(IdentResolver* resolver)
+{
+    for (size_t i = 0; i < resolver->resols_size; ++i) {
+        ident_resol_destroy(&resolver->resols[i]);
+    }
+    free(resolver->resols);
+}
+
+static inline size_t ident_resolver_first_empty(IdentResolver* resolver)
+{
+    size_t i = 0;
+    for (; i < resolver->resols_size; ++i) {
+        if (resolver->resols[i].ty == IdentResolTy_None) {
+            break;
+        }
+    }
+    if (i >= resolver->resols_size) {
+        if (resolver->resols_size + 1 > resolver->resols_capacity) {
+            resolver->resols_capacity *= 2;
+            resolver->resols = realloc(resolver->resols,
+                sizeof(IdentResol) * resolver->resols_capacity);
+        }
+        resolver->resols_size += 1;
+    }
+    return i;
+}
+
+void ident_resolver_define_label(
+    IdentResolver* resolver, char* ident, Loc loc, uint16_t asm_ip)
+{
+    size_t i = ident_resolver_first_empty(resolver);
+    resolver->resols[i] = (IdentResol) {
+        .ident = ident,
+        .loc = loc,
+        .ty = IdentResolTy_Label,
+        .ip = asm_ip * 2,
+    };
+    resolver->current_parent = &resolver->resols[i];
+}
+
+void ident_resolver_define_sublabel(
+    IdentResolver* resolver, char* ident, Loc loc, uint16_t asm_ip)
+{
+    size_t i = ident_resolver_first_empty(resolver);
+    resolver->resols[i] = (IdentResol) {
+        .ident = ident,
+        .loc = loc,
+        .parent = resolver->current_parent,
+        .ty = IdentResolTy_SubLabel,
+        .ip = asm_ip * 2,
+    };
+}
+
+const IdentResol* ident_resolver_resolve(
+    const IdentResolver* resolver, const char* ident)
+{
+    for (size_t i = resolver->resols_size; i > 0; --i) {
+        IdentResol* re = &resolver->resols[i - 1];
+        if (re->ty != IdentResolTy_None && strcmp(re->ident, ident) == 0
+            && (re->ty != IdentResolTy_SubLabel
+                || re->parent == resolver->current_parent)) {
+            return re;
+        }
+    }
+    return NULL;
+}

asm/resolve.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include "report.h"
+#include <stdint.h>
+
+typedef enum {
+    IdentResolTy_None,
+    IdentResolTy_Label,
+    IdentResolTy_SubLabel,
+} IdentResolTy;
+
+typedef struct IdentResol IdentResol;
+struct IdentResol {
+    char* ident;
+    Loc loc;
+    const IdentResol* parent;
+    IdentResolTy ty;
+    union {
+        uint16_t ip;
+    };
+};
+
+void ident_resol_destroy(IdentResol* resol);
+
+typedef struct IdentResolver IdentResolver;
+
+struct IdentResolver {
+    IdentResol* resols;
+    size_t resols_capacity;
+    size_t resols_size;
+    const IdentResol* current_parent;
+};
+void ident_resolver_construct(IdentResolver* resolver);
+void ident_resolver_destroy(IdentResolver* resolver);
+void ident_resolver_define_label(
+    IdentResolver* resolver, char* ident, Loc loc, uint16_t asm_ip);
+void ident_resolver_define_sublabel(
+    IdentResolver* resolver, char* ident, Loc loc, uint16_t asm_ip);
+const IdentResol* ident_resolver_resolve(
+    const IdentResolver* resolver, const char* ident);

asm/str.c

@@ -0,0 +1,28 @@
+#include "str.h"
+#include <stdlib.h>
+#include <string.h>
+
+bool str_includes(const char* str, char ch)
+{
+    for (size_t i = 0; str[i] != '\0'; ++i) {
+        if (str[i] == ch) {
+            return true;
+        }
+    }
+    return false;
+}
+
+char* asm_strdup(const char* str)
+{
+    size_t len = strlen(str);
+    char* val = calloc(len + 1, sizeof(char));
+    strncpy(val, str, len);
+    return val;
+}
+
+char* asm_strndup(const char* str, size_t len)
+{
+    char* val = calloc(len + 1, sizeof(char));
+    strncpy(val, str, len);
+    return val;
+}

asm/str.h

@@ -0,0 +1,8 @@
+#pragma once
+
+#include <stdbool.h>
+#include <stddef.h>
+
+bool str_includes(const char* str, char ch);
+char* asm_strdup(const char* str);
+char* asm_strndup(const char* str, size_t len);

kern/main.asm

@@ -96,16 +96,10 @@ keyboard_interrupt:
     iret
 
 put_char:
-    ; push rbp
-    add rsp, rsp, 2
-    mov u16 [rsp], rbp
+    push rbp
     mov rbp, rsp
-    ; push r1
-    add rsp, rsp, 2
-    mov u16 [rsp], r1
-    ; push r2
-    add rsp, rsp, 2
-    mov u16 [rsp], r2
+    push r1
+    push r2
 
     mov r2, u16 [screen_y]
     mul r2, r2, 40 ; vcd_width_in_ch