Files
gw-basic-2026/src/codegen.c
T
Eremey Valetov 6b63f14b8c Compiler: zero compile errors — all 72 programs compile, 32 pass
Fix last 2 compile errors:
- SWAP with array elements: parse subscripts via emit_to_buf, use
  gwrt_array_elem pointers for both operands
- ENVIRON$/DATE$/TIME$ in expressions: handle 0xFE-prefix tokens in
  both emit_atom (numeric) and emit_str_expr (string) contexts, with
  proper string detection in PRINT

Other fixes:
- RND(n): discard argument via buffer (don't emit inline)
- Float 0.0f: emit "0.0f" not "0f"
- MID$ 3-argument: proper optional length parameter
- FOR scope: static limit/step (no {} blocks)
- RESUME/RESUME NEXT: proper statement handler
- ON TIMER/KEY/COM: skip event traps
- MID$ assignment: skip handler
- ERROR statement: emit gw_error()
- TIMER as expression: emit time() call
- PMAP/ERDEV as expressions: stub values

32/72 tests pass. 0 compile errors. 37 output mismatches. 3 skipped.
2026-03-29 14:04:56 -04:00

1848 lines
56 KiB
C

/*
* C code generator for the GW-BASIC compiler.
*
* Walks the tokenized program (program_line_t linked list) and emits C
* source that calls into the gwrt runtime library. Expressions are
* compiled inline using the same precedence-climbing structure as eval.c.
* All control flow uses goto/labels (no C for/while) so GOTO into loops works.
*/
#include "codegen.h"
#include "gwbasic.h"
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
/* ---- Emit helpers ---- */
static FILE *out;
static analysis_t *ana;
static uint8_t *tp; /* token pointer (mirrors gw.text_ptr) */
static int ret_label_counter;
static int for_label_counter;
/* FOR stack: maps variable to its for_label_counter */
#define FOR_STACK_MAX 16
static struct { char name[2]; gw_valtype_t type; int label; } for_stack[FOR_STACK_MAX];
static int for_stack_sp;
#define EMIT(...) fprintf(out, __VA_ARGS__)
static uint8_t cur(void) { return *tp; }
static uint8_t advance(void)
{
tp++;
while (*tp == ' ') tp++;
return *tp;
}
static void skip_spaces(void) { while (*tp == ' ') tp++; }
/* ---- Token stream readers ---- */
static uint16_t read_int(void)
{
uint8_t tok = *tp;
if (tok >= 0x11 && tok <= 0x1A) { tp++; return tok - 0x11; }
if (tok == TOK_INT1) { uint16_t v = tp[1]; tp += 2; return v; }
if (tok == TOK_INT2) { uint16_t v = tp[1] | (tp[2] << 8); tp += 3; return v; }
return 0;
}
static bool is_const(uint8_t tok)
{
return (tok >= 0x11 && tok <= 0x1A) || tok == TOK_INT1 || tok == TOK_INT2
|| tok == TOK_CONST_SNG || tok == TOK_CONST_DBL;
}
static bool is_letter(uint8_t ch)
{
return (ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z');
}
/* ---- Variable naming ---- */
static const char *type_suffix(gw_valtype_t t)
{
switch (t) {
case VT_INT: return "int";
case VT_SNG: return "sng";
case VT_DBL: return "dbl";
case VT_STR: return "str";
default: return "sng";
}
}
static const char *c_type(gw_valtype_t t)
{
switch (t) {
case VT_INT: return "int16_t";
case VT_SNG: return "float";
case VT_DBL: return "double";
case VT_STR: return "gw_string_t";
default: return "float";
}
}
/* Emit a 2-char name as a C string literal: "AB" or "A" */
static void emit_name_str(const char name[2])
{
if (name[1])
EMIT("\"%c%c\"", name[0], name[1]);
else
EMIT("\"%c\"", name[0]);
}
/* Emit C variable name: var_AB_int */
static void emit_varname(const char name[2], gw_valtype_t type)
{
if (name[1])
EMIT("var_%c%c_%s", toupper(name[0]), toupper(name[1]), type_suffix(type));
else
EMIT("var_%c_%s", toupper(name[0]), type_suffix(type));
}
/* Parse a variable name from the token stream, return its type */
static gw_valtype_t parse_var(char name_out[2])
{
name_out[0] = toupper(cur());
name_out[1] = 0;
advance();
if (is_letter(cur()) || (cur() >= '0' && cur() <= '9')) {
name_out[1] = toupper(cur());
advance();
while (is_letter(cur()) || (cur() >= '0' && cur() <= '9'))
advance();
}
uint8_t suffix = cur();
if (suffix == '$') { advance(); return VT_STR; }
if (suffix == '%') { advance(); return VT_INT; }
if (suffix == '!') { advance(); return VT_SNG; }
if (suffix == '#') { advance(); return VT_DBL; }
int idx = name_out[0] - 'A';
return (idx >= 0 && idx < 26) ? ana->def_type[idx] : VT_SNG;
}
/* ---- Expression compilation ---- */
/* Forward declarations */
static void emit_str_expr(void);
static void emit_num_expr(void);
static int op_prec(uint8_t tok)
{
switch (tok) {
case TOK_IMP: return 40;
case TOK_EQV: return 42;
case TOK_XOR: return 44;
case TOK_OR: return 46;
case TOK_AND: return 48;
case TOK_NOT: return 50;
case TOK_GT: case TOK_EQ: case TOK_LT: return 64;
case TOK_PLUS: case TOK_MINUS: return 121;
case TOK_MOD: return 122;
case TOK_IDIV: return 123;
case TOK_MUL: case TOK_DIV: return 124;
case TOK_POW: return 127;
default: return -1;
}
}
static const char *binop_c(uint8_t tok)
{
switch (tok) {
case TOK_PLUS: return "+";
case TOK_MINUS: return "-";
case TOK_MUL: return "*";
case TOK_DIV: return "/";
case TOK_GT: return ">";
case TOK_LT: return "<";
case TOK_EQ: return "==";
case TOK_AND: return "&";
case TOK_OR: return "|";
case TOK_XOR: return "^";
case TOK_MOD: return "%";
case TOK_IDIV: return "/";
default: return "?";
}
}
/* Forward declarations for buffered expression emission */
static char *emit_to_buf(void (*fn)(int), int arg);
static void emit_num_prec(int min_prec);
static void emit_prec_wrapper(int prec);
/* Emit a numeric atom */
static void emit_atom(void)
{
skip_spaces();
uint8_t tok = cur();
/* Numeric constant */
if (tok >= 0x11 && tok <= 0x1A) {
EMIT("%d", tok - 0x11);
tp++;
return;
}
if (tok == TOK_INT1) {
EMIT("%d", tp[1]);
tp += 2;
return;
}
if (tok == TOK_INT2) {
int16_t v = (int16_t)(tp[1] | (tp[2] << 8));
EMIT("%d", v);
tp += 3;
return;
}
if (tok == TOK_CONST_SNG) {
float v;
memcpy(&v, tp + 1, 4);
tp += 5;
{ char nbuf[32]; snprintf(nbuf, sizeof(nbuf), "%.9g", v);
if (!strchr(nbuf, '.') && !strchr(nbuf, 'e'))
EMIT("%s.0f", nbuf); /* 0 → 0.0f */
else
EMIT("%sf", nbuf); /* 3.14 → 3.14f */
}
return;
}
if (tok == TOK_CONST_DBL) {
double v;
memcpy(&v, tp + 1, 8);
tp += 9;
EMIT("%.17g", v);
return;
}
/* Parenthesized expression */
if (tok == '(') {
EMIT("(");
advance();
emit_num_expr();
if (cur() == ')') advance();
EMIT(")");
return;
}
/* Unary minus */
if (tok == TOK_MINUS) {
EMIT("(-");
advance();
emit_atom();
EMIT(")");
return;
}
/* NOT */
if (tok == TOK_NOT) {
EMIT("(~(int16_t)(");
advance();
emit_num_expr();
EMIT("))");
return;
}
/* Built-in functions (0xFF prefix) */
if (tok == TOK_PREFIX_FF) {
uint8_t func = tp[1];
tp += 2;
skip_spaces();
switch (func) {
case FUNC_ABS:
case FUNC_INT:
case FUNC_SQR:
case FUNC_SIN:
case FUNC_COS:
case FUNC_TAN:
case FUNC_ATN:
case FUNC_LOG:
case FUNC_EXP: {
const char *cfn[] = {
[FUNC_ABS] = "fabs", [FUNC_INT] = "floor", [FUNC_SQR] = "sqrt",
[FUNC_SIN] = "sin", [FUNC_COS] = "cos", [FUNC_TAN] = "tan",
[FUNC_ATN] = "atan", [FUNC_LOG] = "log", [FUNC_EXP] = "exp",
};
EMIT("%s(", cfn[func]);
advance();
emit_num_expr();
if (cur() == ')') advance();
EMIT(")");
return;
}
case FUNC_SGN: {
EMIT("({ double _v = (");
advance(); emit_num_expr();
if (cur() == ')') advance();
EMIT("); (_v > 0) - (_v < 0); })");
return;
}
case FUNC_RND: {
/* RND([n]) — argument is ignored (controls seed behavior) */
if (cur() == '(') {
advance();
/* Consume but discard the argument */
char *discard = emit_to_buf(emit_prec_wrapper, 0);
free(discard);
if (cur() == ')') advance();
}
EMIT("((float)rand() / RAND_MAX)");
return;
}
case FUNC_CINT: {
EMIT("((int16_t)gw_round(");
advance(); emit_num_expr();
if (cur() == ')') advance();
EMIT("))");
return;
}
case FUNC_CSNG: {
EMIT("((float)(");
advance(); emit_num_expr();
if (cur() == ')') advance();
EMIT("))");
return;
}
case FUNC_CDBL: {
EMIT("((double)(");
advance(); emit_num_expr();
if (cur() == ')') advance();
EMIT("))");
return;
}
case FUNC_FIX: {
EMIT("((int16_t)(");
advance(); emit_num_expr();
if (cur() == ')') advance();
EMIT("))");
return;
}
case FUNC_LEN: {
EMIT("gw_fn_len(&(gw_value_t){.type=VT_STR,.sval=");
advance(); emit_str_expr();
if (cur() == ')') advance();
EMIT("}).ival");
return;
}
case FUNC_ASC: {
EMIT("gw_fn_asc(&(gw_value_t){.type=VT_STR,.sval=");
advance(); emit_str_expr();
if (cur() == ')') advance();
EMIT("}).ival");
return;
}
case FUNC_VAL: {
EMIT("gw_fn_val(&(gw_value_t){.type=VT_STR,.sval=");
advance(); emit_str_expr();
if (cur() == ')') advance();
EMIT("}).dval");
return;
}
case 0xD6 /* INSTR */: {
/* INSTR([start,] haystack$, needle$) */
EMIT("gw_fn_instr(1, ");
advance(); /* ( */
/* TODO: handle optional start parameter */
EMIT("&(gw_value_t){.type=VT_STR,.sval=");
emit_str_expr();
EMIT("}, ");
if (cur() == ',') advance();
EMIT("&(gw_value_t){.type=VT_STR,.sval=");
emit_str_expr();
if (cur() == ')') advance();
EMIT("}).ival");
return;
}
case FUNC_POS:
EMIT("(gw_hal ? gw_hal->get_cursor_col() + 1 : 1)");
if (cur() == '(') { advance(); emit_num_expr(); if (cur() == ')') advance(); }
return;
case FUNC_FRE:
EMIT("((float)strpool_free())");
if (cur() == '(') {
advance();
/* consume arg but ignore */
while (cur() && cur() != ')') tp++;
if (cur() == ')') advance();
}
return;
case FUNC_PEEK:
EMIT("virmem_peek(gw.def_seg, ");
advance(); emit_num_expr();
if (cur() == ')') advance();
EMIT(")");
return;
case FUNC_INP:
EMIT("portio_inp(");
advance(); emit_num_expr();
if (cur() == ')') advance();
EMIT(")");
return;
default:
/* Fallback: emit 0 for unhandled functions */
EMIT("0 /* unhandled func 0x%02x */", func);
if (cur() == '(') { advance(); while (cur() && cur() != ')') tp++; if (cur() == ')') advance(); }
return;
}
}
/* Extended expressions (0xFE prefix) — DATE$, TIME$, TIMER, etc. */
if (tok == TOK_PREFIX_FE) {
uint8_t xtok = tp[1];
tp += 2;
skip_spaces();
if (xtok == XSTMT_TIMER) {
EMIT("((float)(time(NULL) %% 86400))"); /* seconds since midnight */
return;
}
/* PMAP as numeric function */
if (xtok == XSTMT_PMAP) {
EMIT("0 /* PMAP */");
if (cur() == '(') { advance(); while (cur() && cur() != ')') tp++; if (cur() == ')') advance(); }
return;
}
/* Other FE tokens used as numeric expressions — emit 0 */
EMIT("0 /* xfunc 0x%02x */", xtok);
return;
}
/* Single-byte function tokens (not 0xFF-prefixed) */
if (tok == TOK_INSTR) {
/* INSTR([start,] haystack$, needle$) */
tp++;
EMIT("({");
if (cur() == '(') advance();
/* Check if first arg is numeric (start position) */
uint8_t *save_p = tp;
bool has_start = false;
/* Heuristic: if first token after ( is a number, it's the start arg */
skip_spaces();
if (is_const(cur()) || (is_letter(cur()) && ({
uint8_t *sv = tp; char n[2]; gw_valtype_t t = parse_var(n); tp = sv; t != VT_STR; }))) {
has_start = true;
}
tp = save_p;
skip_spaces();
if (has_start) {
char *sbuf = emit_to_buf(emit_prec_wrapper, 0);
EMIT(" int _start = (int)(%s);", sbuf);
free(sbuf);
if (cur() == ',') advance();
}
EMIT(" gw_value_t _h = {.type=VT_STR,.sval=");
emit_str_expr();
EMIT("}; ");
if (cur() == ',') advance();
EMIT("gw_value_t _n = {.type=VT_STR,.sval=");
emit_str_expr();
EMIT("}; ");
if (cur() == ')') advance();
if (has_start)
EMIT("gw_fn_instr(_start, &_h, &_n).ival; })");
else
EMIT("gw_fn_instr(1, &_h, &_n).ival; })");
return;
}
if (tok == TOK_CSRLIN) {
tp++;
EMIT("(gw_hal ? gw_hal->get_cursor_row() + 1 : 1)");
return;
}
if (tok == TOK_VARPTR) {
tp++;
EMIT("0 /* VARPTR */");
if (cur() == '(') { advance(); while (cur() && cur() != ')') tp++; if (cur() == ')') advance(); }
return;
}
/* Variable or array element */
if (is_letter(tok)) {
char name[2];
gw_valtype_t type = parse_var(name);
skip_spaces();
if (cur() == '(') {
/* Array element access — buffer subscripts to get ndims */
advance(); /* skip ( */
char *sub_bufs[8];
int ndims = 0;
do {
if (ndims > 0 && cur() == ',') advance();
FILE *orig = out;
char *sbuf = NULL; size_t ssz = 0;
out = open_memstream(&sbuf, &ssz);
emit_num_expr();
fclose(out);
out = orig;
sub_bufs[ndims++] = sbuf;
} while (cur() == ',' && ndims < 8);
if (cur() == ')') advance();
EMIT("gwrt_array_elem("); emit_name_str(name);
EMIT(", %d, %d, (int[]){", type, ndims);
for (int d = 0; d < ndims; d++) {
if (d > 0) EMIT(", ");
EMIT("(int)(%s)", sub_bufs[d]);
free(sub_bufs[d]);
}
EMIT("})->");
switch (type) {
case VT_INT: EMIT("ival"); break;
case VT_SNG: EMIT("fval"); break;
case VT_DBL: EMIT("dval"); break;
default: EMIT("fval"); break;
}
return;
}
if (type == VT_STR) {
EMIT("0 /* str var in num ctx */");
} else {
emit_varname(name, type);
}
return;
}
/* Fallback */
EMIT("0 /* unknown tok 0x%02x */", tok);
tp++;
}
/* Emit numeric expression with precedence climbing.
*
* MOD/IDIV/POW need special treatment since C's % doesn't work on floats,
* \ is integer division, and ^ is pow(). We use a prefix-wrapping trick:
* before emitting the left operand, check if the upcoming operator needs
* a function wrapper, and if so, emit the function name + open paren first.
*/
static void emit_num_prec(int min_prec);
/* Buffer helper: emit to a memory buffer, return allocated string */
static char *emit_to_buf(void (*fn)(int), int arg)
{
FILE *orig = out;
char *buf = NULL;
size_t sz = 0;
out = open_memstream(&buf, &sz);
fn(arg);
fclose(out);
out = orig;
return buf;
}
static void emit_atom_wrapper(int unused) { (void)unused; emit_atom(); }
static void emit_prec_wrapper(int prec) { emit_num_prec(prec); }
static void emit_num_prec(int min_prec)
{
/* Buffer left operand so we can wrap it for MOD/IDIV/POW */
char *left = emit_to_buf(emit_atom_wrapper, 0);
for (;;) {
skip_spaces();
int prec = op_prec(cur());
if (prec < min_prec) break;
uint8_t op = cur();
advance();
/* Handle combined relationals: <=, >=, <> */
const char *cop = NULL;
if (op == TOK_LT && cur() == TOK_EQ) { advance(); cop = "<="; }
else if (op == TOK_GT && cur() == TOK_EQ) { advance(); cop = ">="; }
else if (op == TOK_LT && cur() == TOK_GT) { advance(); cop = "!="; }
else if (op == TOK_GT && cur() == TOK_LT) { advance(); cop = "!="; }
else if (op == TOK_EQ && cur() == TOK_LT) { advance(); cop = "<="; }
else if (op == TOK_EQ && cur() == TOK_GT) { advance(); cop = ">="; }
char *right = emit_to_buf(emit_prec_wrapper, prec + 1);
char *combined = NULL;
size_t csz = 0;
FILE *cm = open_memstream(&combined, &csz);
if (cop) {
fprintf(cm, "((%s %s %s) ? -1 : 0)", left, cop, right);
} else if (op == TOK_GT || op == TOK_LT || op == TOK_EQ) {
fprintf(cm, "((%s %s %s) ? -1 : 0)", left, binop_c(op), right);
} else if (op == TOK_MOD) {
fprintf(cm, "((int16_t)(%s) %% (int16_t)(%s))", left, right);
} else if (op == TOK_IDIV) {
fprintf(cm, "((int16_t)(%s) / (int16_t)(%s))", left, right);
} else if (op == TOK_POW) {
fprintf(cm, "pow((double)(%s), (double)(%s))", left, right);
} else {
fprintf(cm, "(%s %s %s)", left, binop_c(op), right);
}
fclose(cm);
free(left);
free(right);
left = combined;
}
EMIT("%s", left);
free(left);
}
static void emit_num_expr(void)
{
emit_num_prec(0);
}
/* Emit a string expression */
static void emit_str_expr(void)
{
skip_spaces();
uint8_t tok = cur();
/* String literal */
if (tok == '"') {
EMIT("gw_str_from_cstr(\"");
tp++;
while (*tp && *tp != '"') {
if (*tp == '\\' || *tp == '"') EMIT("\\");
EMIT("%c", *tp);
tp++;
}
if (*tp == '"') tp++;
EMIT("\")");
/* Handle concatenation */
skip_spaces();
while (cur() == TOK_PLUS) {
advance();
EMIT("; _cat = gw_str_concat(&(gw_value_t){.type=VT_STR,.sval=_cat.sval}, &(gw_value_t){.type=VT_STR,.sval=");
emit_str_expr();
EMIT("})");
}
return;
}
/* String functions (0xFF prefix) */
if (tok == TOK_PREFIX_FF) {
uint8_t func = tp[1];
tp += 2;
skip_spaces();
switch (func) {
case FUNC_CHR:
EMIT("gw_fn_chr(");
advance(); emit_num_expr();
if (cur() == ')') advance();
EMIT(").sval");
return;
case FUNC_STR:
EMIT("gw_fn_str(&(gw_value_t){.type=VT_DBL,.dval=(double)(");
advance(); emit_num_expr();
if (cur() == ')') advance();
EMIT(")}).sval");
return;
case FUNC_LEFT: {
EMIT("gw_fn_left(&(gw_value_t){.type=VT_STR,.sval=");
advance(); emit_str_expr();
if (cur() == ',') advance();
EMIT("}, ");
emit_num_expr();
if (cur() == ')') advance();
EMIT(").sval");
return;
}
case FUNC_RIGHT: {
EMIT("gw_fn_right(&(gw_value_t){.type=VT_STR,.sval=");
advance(); emit_str_expr();
if (cur() == ',') advance();
EMIT("}, ");
emit_num_expr();
if (cur() == ')') advance();
EMIT(").sval");
return;
}
case FUNC_MID: {
EMIT("gw_fn_mid(&(gw_value_t){.type=VT_STR,.sval=");
advance(); emit_str_expr();
if (cur() == ',') advance();
EMIT("}, (int)(");
emit_num_expr();
EMIT("), ");
if (cur() == ',') {
advance();
EMIT("(int)(");
emit_num_expr();
EMIT(")");
} else {
EMIT("255");
}
if (cur() == ')') advance();
EMIT(").sval");
return;
}
case FUNC_SPACE:
EMIT("gw_fn_space(");
advance(); emit_num_expr();
if (cur() == ')') advance();
EMIT(").sval");
return;
case 0xD4 /* STRING$ */:
EMIT("gw_fn_strings(");
advance(); emit_num_expr();
if (cur() == ',') advance();
EMIT(", ");
emit_num_expr();
if (cur() == ')') advance();
EMIT(").sval");
return;
case FUNC_HEX:
EMIT("gw_fn_hex(");
advance(); emit_num_expr();
if (cur() == ')') advance();
EMIT(").sval");
return;
case FUNC_OCT:
EMIT("gw_fn_oct(");
advance(); emit_num_expr();
if (cur() == ')') advance();
EMIT(").sval");
return;
default:
EMIT("gw_str_from_cstr(\"\") /* unhandled str func */");
return;
}
}
/* Extended string expressions (0xFE prefix) — DATE$, TIME$, ENVIRON$ */
if (tok == TOK_PREFIX_FE) {
uint8_t xtok = tp[1];
tp += 2;
skip_spaces();
if (xtok == XSTMT_DATE) {
EMIT("({time_t _t=time(NULL); struct tm *_tm=localtime(&_t);"
" char _db[16]; snprintf(_db,16,\"%%02d-%%02d-%%04d\","
"_tm->tm_mon+1,_tm->tm_mday,_tm->tm_year+1900);"
" gw_str_from_cstr(_db);})");
return;
}
if (xtok == XSTMT_TIME) {
EMIT("({time_t _t=time(NULL); struct tm *_tm=localtime(&_t);"
" char _tb[16]; snprintf(_tb,16,\"%%02d:%%02d:%%02d\","
"_tm->tm_hour,_tm->tm_min,_tm->tm_sec);"
" gw_str_from_cstr(_tb);})");
return;
}
if (xtok == XSTMT_ENVIRON) {
/* ENVIRON$("name") */
if (cur() == '$') advance();
if (cur() == '(') advance();
EMIT("({gw_string_t _a=");
emit_str_expr();
if (cur() == ')') advance();
EMIT("; char *_n=gw_str_to_cstr(&_a); gw_str_free(&_a);"
" const char *_v=getenv(_n);"
" gw_string_t _r=gw_str_from_cstr(_v?_v:\"\");"
" free(_n); _r;})");
return;
}
if (xtok == XSTMT_ERDEV) {
if (cur() == '$') advance();
EMIT("gw_str_from_cstr(\"\")");
return;
}
EMIT("gw_str_from_cstr(\"\") /* unhandled xstr 0x%02x */", xtok);
return;
}
/* STRING$ (single-byte token 0xD4) */
if (tok == TOK_STRINGS) {
tp++;
if (cur() == '(') advance();
char *arg1 = emit_to_buf(emit_prec_wrapper, 0);
if (cur() == ',') advance();
skip_spaces();
/* Second arg can be a number (char code) or a string */
if (cur() == '"' || (is_letter(cur()) && ({
uint8_t *sv = tp; char n[2]; gw_valtype_t t = parse_var(n); tp = sv; t == VT_STR; }))) {
/* String second arg — use first char's ASCII value */
char *arg2 = emit_to_buf(emit_prec_wrapper, 0);
EMIT("gw_fn_strings((int)(%s), (int)(%s)).sval", arg1, arg2);
free(arg2);
} else {
char *arg2 = emit_to_buf(emit_prec_wrapper, 0);
EMIT("gw_fn_strings((int)(%s), (int)(%s)).sval", arg1, arg2);
free(arg2);
}
free(arg1);
if (cur() == ')') advance();
return;
}
/* String variable or array element */
if (is_letter(tok)) {
char name[2];
gw_valtype_t type = parse_var(name);
skip_spaces();
if (cur() == '(' && type == VT_STR) {
/* String array element */
advance();
char *sub_bufs[8]; int ndims = 0;
do {
if (ndims > 0 && cur() == ',') advance();
FILE *orig = out; char *sb = NULL; size_t ss = 0;
out = open_memstream(&sb, &ss);
emit_num_expr();
fclose(out); out = orig;
sub_bufs[ndims++] = sb;
} while (cur() == ',' && ndims < 8);
if (cur() == ')') advance();
EMIT("gw_str_copy(&gwrt_array_elem("); emit_name_str(name);
EMIT(", %d, %d, (int[]){", type, ndims);
for (int d = 0; d < ndims; d++) {
if (d > 0) EMIT(", ");
EMIT("(int)(%s)", sub_bufs[d]);
free(sub_bufs[d]);
}
EMIT("})->sval)");
return;
}
if (type == VT_STR) {
EMIT("gw_str_copy(&");
emit_varname(name, type);
EMIT(")");
} else {
EMIT("gw_str_from_cstr(\"\") /* num var in str ctx */");
}
return;
}
EMIT("gw_str_from_cstr(\"\") /* unknown str expr */");
}
/* ---- Statement compilation ---- */
static void emit_stmt(void);
/* Peek at the next expression to guess its result type.
* Only returns VT_INT for pure integer atoms (no operators).
* For anything involving operators, returns the variable/constant type. */
static gw_valtype_t peek_expr_type(void)
{
uint8_t *save = tp;
skip_spaces();
uint8_t tok = cur();
/* Variable — check suffix (most important case) */
if (is_letter(tok)) {
char name[2];
gw_valtype_t type = parse_var(name);
tp = save;
return type;
}
/* Double constant */
if (tok == TOK_CONST_DBL) { tp = save; return VT_DBL; }
/* Single constant */
if (tok == TOK_CONST_SNG) { tp = save; return VT_SNG; }
/* Unary minus — peek past it */
if (tok == TOK_MINUS) { advance(); gw_valtype_t t = peek_expr_type(); tp = save; return t; }
/* Functions */
if (tok == TOK_PREFIX_FF) {
uint8_t func = tp[1];
tp = save;
switch (func) {
case FUNC_LEN: case FUNC_ASC: case FUNC_CINT: case FUNC_FIX:
case FUNC_POS: case FUNC_PEEK: case FUNC_INP:
return VT_INT;
case FUNC_VAL: case FUNC_ATN: case FUNC_LOG: case FUNC_EXP:
case FUNC_CDBL:
return VT_DBL;
default:
return VT_SNG;
}
}
/* Integer constants — only if truly standalone (PRINT 42 vs PRINT 4*X) */
if ((tok >= 0x11 && tok <= 0x1A) || tok == TOK_INT1 || tok == TOK_INT2)
{ tp = save; return VT_SNG; } /* default to SNG for safety */
tp = save;
return VT_SNG;
}
static void emit_print(void)
{
skip_spaces();
bool need_newline = true;
while (cur() && cur() != ':' && cur() != TOK_ELSE) {
skip_spaces();
if (cur() == ';') {
need_newline = false;
advance();
continue;
}
if (cur() == ',') {
EMIT(" gwrt_print_tab();\n");
need_newline = false;
advance();
continue;
}
/* Detect string vs numeric expression */
/* String: starts with " or a string variable or string function */
uint8_t tok = cur();
bool is_str = (tok == '"' || tok == TOK_STRINGS);
if (is_letter(tok)) {
uint8_t *save = tp;
char name[2];
gw_valtype_t type = parse_var(name);
tp = save;
is_str = (type == VT_STR);
}
if (tok == TOK_PREFIX_FF) {
uint8_t func = tp[1];
is_str = (func == FUNC_CHR || func == FUNC_STR || func == FUNC_LEFT
|| func == FUNC_RIGHT || func == FUNC_MID || func == FUNC_SPACE
|| func == FUNC_HEX || func == FUNC_OCT);
}
/* FE-prefix string functions: ENVIRON$, DATE$, TIME$, ERDEV$ */
if (tok == TOK_PREFIX_FE) {
uint8_t xtok = tp[1];
/* Check if followed by $ (string form) */
if (xtok == XSTMT_ENVIRON || xtok == XSTMT_ERDEV)
is_str = true; /* ENVIRON$/ERDEV$ detected at '$' in emit_str_expr */
if (xtok == XSTMT_DATE || xtok == XSTMT_TIME)
is_str = true;
}
if (is_str) {
EMIT(" { gw_string_t _s = ");
emit_str_expr();
EMIT("; gwrt_print_str(_s); gw_str_free(&_s); }\n");
} else {
gw_valtype_t etype = peek_expr_type();
switch (etype) {
case VT_INT:
EMIT(" { gw_value_t _pv = {.type = VT_INT, .ival = (int16_t)(");
emit_num_expr();
EMIT(")}; gw_print_value(&_pv); }\n");
break;
case VT_DBL:
EMIT(" { gw_value_t _pv = {.type = VT_DBL, .dval = (double)(");
emit_num_expr();
EMIT(")}; gw_print_value(&_pv); }\n");
break;
default:
EMIT(" { gw_value_t _pv = {.type = VT_SNG, .fval = (float)(");
emit_num_expr();
EMIT(")}; gw_print_value(&_pv); }\n");
break;
}
}
need_newline = true;
}
if (need_newline)
EMIT(" gwrt_print_newline();\n");
}
static void emit_assignment(void)
{
char name[2];
gw_valtype_t type = parse_var(name);
skip_spaces();
/* Array element assignment: A(i) = expr */
if (cur() == '(') {
advance(); /* skip ( */
EMIT(" { int _subs[] = {(int)(");
emit_num_expr();
int ndims = 1;
while (cur() == ',') {
advance();
EMIT("), (int)(");
emit_num_expr();
ndims++;
}
EMIT(")};\n");
if (cur() == ')') advance();
skip_spaces();
if (cur() == TOK_EQ) advance();
/* Call runtime to get element pointer */
EMIT(" gw_value_t *_elem = gwrt_array_elem(");
emit_name_str(name);
EMIT(", %d, %d, _subs);\n", type, ndims);
if (type == VT_STR) {
EMIT(" gw_str_free(&_elem->sval);\n");
EMIT(" _elem->sval = ");
emit_str_expr();
EMIT(";\n _elem->type = VT_STR;\n");
} else {
EMIT(" *_elem = (gw_value_t){.type=%d};\n", type);
switch (type) {
case VT_INT: EMIT(" _elem->ival = (int16_t)("); break;
case VT_SNG: EMIT(" _elem->fval = (float)("); break;
case VT_DBL: EMIT(" _elem->dval = (double)("); break;
default: EMIT(" _elem->fval = (float)("); break;
}
emit_num_expr();
EMIT(");\n");
}
EMIT(" }\n");
return;
}
if (cur() != TOK_EQ) {
EMIT(" /* expected = */\n");
return;
}
advance();
if (type == VT_STR) {
EMIT(" gw_str_free(&");
emit_varname(name, type);
EMIT(");\n");
EMIT(" ");
emit_varname(name, type);
EMIT(" = ");
emit_str_expr();
EMIT(";\n");
} else {
EMIT(" ");
emit_varname(name, type);
EMIT(" = (%s)(", c_type(type));
emit_num_expr();
EMIT(");\n");
}
}
/* Compile one statement */
static void emit_stmt(void)
{
skip_spaces();
uint8_t tok = cur();
if (tok == 0 || tok == ':') return;
/* REM */
if (tok == TOK_REM || tok == TOK_SQUOTE) {
while (*tp) tp++;
return;
}
/* PRINT */
if (tok == TOK_PRINT || tok == '?') {
advance();
skip_spaces();
/* PRINT USING — embed token bytes and call runtime */
if (cur() == TOK_USING) {
/* Skip past USING token, then embed remaining bytes */
advance(); /* skip TOK_USING */
uint8_t *start = tp;
while (*tp && *tp != ':') tp++;
int len = (int)(tp - start);
/* Sync compiled variables to interpreter table so gw_eval works */
EMIT(" {\n");
for (int vi = 0; vi < ana->var_count; vi++) {
var_info_t *v = &ana->vars[vi];
char n0 = v->name[0], n1 = v->name[1];
if (n1)
EMIT(" gw_var_find_or_create(\"%c%c\", %d)->val = ", n0, n1, v->type);
else
EMIT(" gw_var_find_or_create(\"%c\", %d)->val = ", n0, v->type);
EMIT("(gw_value_t){.type=%d,", v->type);
switch (v->type) {
case VT_INT: EMIT(".ival="); break;
case VT_SNG: EMIT(".fval="); break;
case VT_DBL: EMIT(".dval="); break;
case VT_STR: EMIT(".sval="); break;
}
emit_varname(v->name, v->type);
EMIT("};\n");
}
EMIT(" static const uint8_t _pu[] = {");
for (int i = 0; i < len; i++)
EMIT("%s%u", i ? "," : "", start[i]);
EMIT(",0};\n");
EMIT(" gw.text_ptr = (uint8_t *)_pu;\n");
EMIT(" gw_print_using(NULL);\n }\n");
return;
}
/* PRINT # (file) — skip for now */
if (cur() == '#') {
while (cur() && cur() != ':' && cur() != 0) tp++;
EMIT(" /* PRINT# — not yet compiled */\n");
return;
}
emit_print();
return;
}
/* GOTO */
if (tok == TOK_GOTO) {
advance();
skip_spaces();
uint16_t target = read_int();
EMIT(" goto L_%u;\n", target);
return;
}
/* GOSUB */
if (tok == TOK_GOSUB) {
advance();
skip_spaces();
uint16_t target = read_int();
int rl = ret_label_counter++;
EMIT(" gwrt_gosub_push(%d); goto L_%u;\n", rl, target);
EMIT("ret_%d: ;\n", rl);
return;
}
/* RETURN */
if (tok == TOK_RETURN) {
advance();
EMIT(" switch(gwrt_gosub_pop()) {\n");
for (int i = 0; i < ret_label_counter; i++)
EMIT(" case %d: goto ret_%d;\n", i, i);
EMIT(" }\n");
return;
}
/* FOR */
if (tok == TOK_FOR) {
advance();
char name[2];
gw_valtype_t type = parse_var(name);
skip_spaces();
if (cur() == TOK_EQ) advance();
EMIT(" ");
emit_varname(name, type);
EMIT(" = (%s)(", c_type(type));
emit_num_expr();
EMIT(");\n");
skip_spaces();
if (cur() == TOK_TO) advance();
/* Store limit and step at function scope (no {} block — FOR may span IF THEN) */
EMIT(" static %s _for_limit_%d; _for_limit_%d = (%s)(",
c_type(type), for_label_counter, for_label_counter, c_type(type));
emit_num_expr();
EMIT(");\n");
EMIT(" static %s _for_step_%d; _for_step_%d = 1;\n",
c_type(type), for_label_counter, for_label_counter);
skip_spaces();
if (cur() == TOK_STEP) {
advance();
EMIT(" _for_step_%d = (%s)(", for_label_counter, c_type(type));
emit_num_expr();
EMIT(");\n");
}
int fc = for_label_counter++;
EMIT(" for_top_%d:\n", fc);
EMIT(" if (_for_step_%d >= 0 ? ", fc);
emit_varname(name, type);
EMIT(" > _for_limit_%d : ", fc);
emit_varname(name, type);
EMIT(" < _for_limit_%d) goto for_done_%d;\n", fc, fc);
/* Push onto FOR stack */
if (for_stack_sp < FOR_STACK_MAX) {
for_stack[for_stack_sp].name[0] = name[0];
for_stack[for_stack_sp].name[1] = name[1];
for_stack[for_stack_sp].type = type;
for_stack[for_stack_sp].label = fc;
for_stack_sp++;
}
return;
}
/* NEXT [var] */
if (tok == TOK_NEXT) {
advance();
skip_spaces();
/* Find matching FOR on the stack */
int fc = -1;
if (is_letter(cur())) {
char name[2];
gw_valtype_t type = parse_var(name);
/* Search stack from top for matching variable */
for (int i = for_stack_sp - 1; i >= 0; i--) {
if (for_stack[i].name[0] == name[0] &&
for_stack[i].name[1] == name[1] &&
for_stack[i].type == type) {
fc = for_stack[i].label;
for_stack_sp = i; /* pop this and everything above */
break;
}
}
if (fc < 0) fc = for_label_counter > 0 ? for_label_counter - 1 : 0;
EMIT(" ");
emit_varname(name, type);
EMIT(" += _for_step_%d;\n", fc);
} else {
/* NEXT without variable — match most recent FOR */
if (for_stack_sp > 0) {
for_stack_sp--;
fc = for_stack[for_stack_sp].label;
} else {
fc = for_label_counter > 0 ? for_label_counter - 1 : 0;
}
}
EMIT(" goto for_top_%d;\n", fc);
EMIT(" for_done_%d: ;\n", fc);
return;
}
/* WHILE */
if (tok == TOK_WHILE) {
int wl = for_label_counter++;
EMIT(" while_top_%d:\n", wl);
advance();
EMIT(" if (!(");
emit_num_expr();
EMIT(")) goto while_done_%d;\n", wl);
/* Push on FOR stack (reuse for WEND matching) */
if (for_stack_sp < FOR_STACK_MAX) {
for_stack[for_stack_sp].name[0] = 'W';
for_stack[for_stack_sp].name[1] = 0;
for_stack[for_stack_sp].type = VT_INT;
for_stack[for_stack_sp].label = wl;
for_stack_sp++;
}
return;
}
/* WEND */
if (tok == TOK_WEND) {
advance();
int wl = 0;
if (for_stack_sp > 0) {
for_stack_sp--;
wl = for_stack[for_stack_sp].label;
}
EMIT(" goto while_top_%d;\n", wl);
EMIT(" while_done_%d: ;\n", wl);
return;
}
/* ON n GOTO / ON n GOSUB */
if (tok == TOK_ON) {
advance();
skip_spaces();
/* Check for ON ERROR GOTO */
if (cur() == TOK_ERROR) {
advance(); skip_spaces();
if (cur() == TOK_GOTO) {
advance(); skip_spaces();
uint16_t target = read_int();
EMIT(" gwrt_error_target = %u; /* ON ERROR GOTO */\n", target);
}
return;
}
/* ON TIMER / ON KEY / ON COM — event trapping, skip */
if (cur() == TOK_PREFIX_FE || cur() == TOK_KEY) {
EMIT(" /* ON event trap — not compiled */\n");
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
EMIT(" { int _on_val = (int)(");
emit_num_expr();
EMIT(");\n");
skip_spaces();
if (cur() == TOK_GOTO) {
advance(); skip_spaces();
int n = 1;
EMIT(" switch(_on_val) {\n");
while (is_const(cur())) {
uint16_t target = read_int();
EMIT(" case %d: goto L_%u;\n", n++, target);
skip_spaces();
if (cur() == ',') { advance(); skip_spaces(); }
else break;
}
EMIT(" }\n }\n");
} else if (cur() == TOK_GOSUB) {
advance(); skip_spaces();
int n = 1;
int rl = ret_label_counter;
EMIT(" switch(_on_val) {\n");
while (is_const(cur())) {
uint16_t target = read_int();
EMIT(" case %d: gwrt_gosub_push(%d); goto L_%u;\n", n++, rl, target);
skip_spaces();
if (cur() == ',') { advance(); skip_spaces(); }
else break;
}
EMIT(" }\n }\n");
EMIT(" ret_%d: ;\n", rl);
ret_label_counter++;
}
return;
}
/* DIM */
if (tok == TOK_DIM) {
advance();
while (cur() && cur() != ':' && cur() != 0) {
skip_spaces();
if (!is_letter(cur())) break;
char name[2];
gw_valtype_t type = parse_var(name);
skip_spaces();
if (cur() != '(') break;
advance();
/* Buffer dimensions */
char *dim_bufs[8]; int ndims = 0;
do {
if (ndims > 0 && cur() == ',') advance();
FILE *orig = out; char *db = NULL; size_t ds = 0;
out = open_memstream(&db, &ds);
emit_num_expr();
fclose(out); out = orig;
dim_bufs[ndims++] = db;
} while (cur() == ',' && ndims < 8);
if (cur() == ')') advance();
EMIT(" gwrt_dim("); emit_name_str(name);
EMIT(", %d, %d, (int[]){", type, ndims);
for (int d = 0; d < ndims; d++) {
if (d > 0) EMIT(", ");
EMIT("(int)(%s)", dim_bufs[d]);
free(dim_bufs[d]);
}
EMIT("});\n");
skip_spaces();
if (cur() == ',') advance();
else break;
}
return;
}
/* SWAP */
if (tok == TOK_SWAP) {
advance();
/* Parse both operands, emit as pointer swaps */
EMIT(" {\n");
for (int si = 0; si < 2; si++) {
skip_spaces();
if (si == 1 && cur() == ',') advance();
skip_spaces();
char name[2];
gw_valtype_t type = parse_var(name);
skip_spaces();
if (cur() == '(') {
/* Array element */
advance();
char *sbufs[8]; int nd = 0;
do {
if (nd > 0 && cur() == ',') advance();
sbufs[nd++] = emit_to_buf(emit_prec_wrapper, 0);
} while (cur() == ',' && nd < 8);
if (cur() == ')') advance();
EMIT(" gw_value_t *_sw%d = gwrt_array_elem(", si);
emit_name_str(name);
EMIT(", %d, %d, (int[]){", type, nd);
for (int d = 0; d < nd; d++) {
if (d > 0) EMIT(",");
EMIT("(int)(%s)", sbufs[d]);
free(sbufs[d]);
}
EMIT("});\n");
} else {
/* Scalar: wrap in a static gw_value_t so we have a pointer */
EMIT(" static gw_value_t _swv%d; _swv%d.type = %d; ",
si, si, type);
switch (type) {
case VT_INT: EMIT("_swv%d.ival = ", si); break;
case VT_SNG: EMIT("_swv%d.fval = ", si); break;
case VT_DBL: EMIT("_swv%d.dval = ", si); break;
case VT_STR: EMIT("_swv%d.sval = ", si); break;
}
emit_varname(name, type);
EMIT(";\n gw_value_t *_sw%d = &_swv%d;\n", si, si);
}
}
EMIT(" gw_value_t _tmp = *_sw0; *_sw0 = *_sw1; *_sw1 = _tmp;\n");
/* For scalar operands, write back from the wrapper */
EMIT(" }\n");
return;
}
/* POKE */
if (tok == TOK_POKE) {
advance();
EMIT(" virmem_poke(gw.def_seg, (uint16_t)(");
emit_num_expr();
EMIT("), (uint8_t)(");
skip_spaces();
if (cur() == ',') advance();
emit_num_expr();
EMIT("));\n");
return;
}
/* DEF SEG / DEF FN */
if (tok == TOK_DEF) {
advance();
skip_spaces();
/* DEF SEG = expr or DEF FN */
if (toupper(cur()) == 'S') {
/* Skip "SEG" */
while (is_letter(cur())) advance();
skip_spaces();
if (cur() == TOK_EQ) {
advance();
EMIT(" gw.def_seg = (uint16_t)(");
emit_num_expr();
EMIT(");\n");
} else {
EMIT(" gw.def_seg = 0;\n");
}
} else {
/* DEF FN — skip for now, handled by analysis */
while (cur() && cur() != ':' && cur() != 0) tp++;
}
return;
}
/* RANDOMIZE */
if (tok == TOK_RANDOMIZE) {
advance();
skip_spaces();
if (cur() && cur() != ':' && cur() != 0) {
EMIT(" srand((unsigned)(");
emit_num_expr();
EMIT("));\n");
} else {
EMIT(" srand((unsigned)time(NULL));\n");
}
return;
}
/* COLOR */
if (tok == TOK_COLOR) {
advance();
EMIT(" /* COLOR */\n");
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
/* LOCATE */
if (tok == TOK_LOCATE) {
advance();
EMIT(" { int _row = (int)(");
emit_num_expr();
EMIT("); int _col = 1;\n");
skip_spaces();
if (cur() == ',') {
advance();
EMIT(" _col = (int)(");
emit_num_expr();
EMIT(");\n");
}
EMIT(" if (gw_hal) gw_hal->locate(_row - 1, _col - 1); }\n");
return;
}
/* WIDTH */
if (tok == TOK_WIDTH) {
advance();
EMIT(" /* WIDTH */\n");
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
/* SCREEN */
if (tok == TOK_SCREEN) {
advance();
EMIT(" { int _mode = (int)(");
emit_num_expr();
EMIT("); if (_mode) gfx_init(_mode); else gfx_shutdown(); }\n");
while (cur() == ',') { advance(); emit_num_expr(); }
return;
}
/* OPEN / CLOSE — file I/O (Phase 3: needs inline argument parsing) */
if (tok == TOK_OPEN || tok == TOK_CLOSE) {
EMIT(" /* %s — file I/O not yet compiled */\n", tok == TOK_OPEN ? "OPEN" : "CLOSE");
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
/* INPUT */
if (tok == TOK_INPUT) {
advance();
EMIT(" /* INPUT — not yet compiled */\n");
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
/* RESUME / RESUME NEXT / RESUME n */
if (tok == TOK_RESUME) {
advance();
skip_spaces();
if (cur() == TOK_NEXT) {
advance();
EMIT(" /* RESUME NEXT — not fully compiled */\n");
} else if (is_const(cur())) {
uint16_t target = read_int();
EMIT(" goto L_%u; /* RESUME n */\n", target);
} else {
EMIT(" /* RESUME — not fully compiled */\n");
}
return;
}
/* ERROR n */
if (tok == TOK_ERROR) {
advance();
EMIT(" gw_error((int)(");
emit_num_expr();
EMIT("));\n");
return;
}
/* ERASE */
if (tok == TOK_ERASE) {
advance();
EMIT(" /* ERASE — not yet compiled */\n");
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
/* TRON/TROFF */
if (tok == TOK_TRON) { advance(); return; }
if (tok == TOK_TROFF) { advance(); return; }
/* OPTION BASE */
if (tok == TOK_OPTION) {
advance(); /* skip OPTION */
skip_spaces();
/* expect BASE */
advance(); /* skip BASE */
skip_spaces();
EMIT(" gw.option_base = (int)(");
emit_num_expr();
EMIT(");\n");
return;
}
/* DEFINT/DEFSNG/DEFDBL/DEFSTR — compile-time only, skip */
if (tok == TOK_DEFINT || tok == TOK_DEFSNG ||
tok == TOK_DEFDBL || tok == TOK_DEFSTR) {
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
/* KEY */
if (tok == TOK_KEY) {
advance();
EMIT(" /* KEY */\n");
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
/* WRITE (output) */
if (tok == TOK_WRITE) {
advance();
skip_spaces();
/* Simple WRITE: comma-separated values with quotes around strings */
bool first = true;
while (cur() && cur() != ':' && cur() != 0) {
if (!first) EMIT(" gwrt_print_cstr(\",\");\n");
first = false;
skip_spaces();
if (cur() == '"' || (is_letter(cur()) && ({
uint8_t *s = tp; char n[2]; gw_valtype_t t = parse_var(n);
tp = s; t == VT_STR; }))) {
EMIT(" gwrt_print_cstr(\"\\\"\");\n");
EMIT(" { gw_string_t _s = ");
emit_str_expr();
EMIT("; gwrt_print_str(_s); gw_str_free(&_s); }\n");
EMIT(" gwrt_print_cstr(\"\\\"\");\n");
} else {
EMIT(" { gw_value_t _pv = {.type = VT_SNG, .fval = (float)(");
emit_num_expr();
EMIT(")}; gw_print_value(&_pv); }\n");
}
skip_spaces();
if (cur() == ',') advance();
else break;
}
EMIT(" gwrt_print_newline();\n");
return;
}
/* IF / THEN / ELSE */
if (tok == TOK_IF) {
advance();
EMIT(" if ((");
emit_num_expr();
EMIT(") != 0) {\n");
skip_spaces();
if (cur() == TOK_THEN) advance();
skip_spaces();
/* THEN followed by line number? */
if (is_const(cur())) {
uint16_t target = read_int();
EMIT(" goto L_%u;\n", target);
} else {
/* THEN followed by statements */
while (cur() && cur() != TOK_ELSE && cur() != 0) {
if (cur() == ':') { advance(); continue; }
emit_stmt();
}
}
if (cur() == TOK_ELSE) {
advance();
EMIT(" } else {\n");
skip_spaces();
if (is_const(cur())) {
uint16_t target = read_int();
EMIT(" goto L_%u;\n", target);
} else {
while (cur() && cur() != 0) {
if (cur() == ':') { advance(); continue; }
emit_stmt();
}
}
}
EMIT(" }\n");
return;
}
/* END */
if (tok == TOK_END) {
advance();
EMIT(" gwrt_shutdown(); return 0;\n");
return;
}
/* STOP */
if (tok == TOK_STOP) {
advance();
EMIT(" gwrt_shutdown(); return 0;\n");
return;
}
/* Extended statements (0xFE prefix) */
if (tok == TOK_PREFIX_FE) {
uint8_t xstmt = tp[1];
tp += 2;
skip_spaces();
if (xstmt == XSTMT_SYSTEM) {
EMIT(" gwrt_shutdown(); exit(0);\n");
return;
}
if (xstmt == XSTMT_FILES || xstmt == XSTMT_SHELL ||
xstmt == XSTMT_CHDIR || xstmt == XSTMT_MKDIR ||
xstmt == XSTMT_RMDIR || xstmt == XSTMT_KILL ||
xstmt == XSTMT_NAME) {
/* These need a string argument — emit runtime call */
EMIT(" /* xstmt 0x%02x — runtime call needed */\n", xstmt);
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
if (xstmt == XSTMT_TIMER) {
/* TIMER ON/OFF/STOP */
EMIT(" /* TIMER trap */\n");
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
if (xstmt == XSTMT_CIRCLE || xstmt == XSTMT_DRAW ||
xstmt == XSTMT_PAINT || xstmt == XSTMT_PLAY) {
/* Graphics/sound — skip args for now */
EMIT(" /* graphics/sound xstmt 0x%02x */\n", xstmt);
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
if (xstmt == XSTMT_VIEW || xstmt == XSTMT_WINDOW ||
xstmt == XSTMT_PALETTE) {
EMIT(" /* view/window/palette */\n");
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
if (xstmt == XSTMT_FIELD || xstmt == XSTMT_LSET ||
xstmt == XSTMT_RSET || xstmt == XSTMT_PUT ||
xstmt == XSTMT_GET) {
EMIT(" /* file I/O xstmt */\n");
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
if (xstmt == XSTMT_COMMON || xstmt == XSTMT_CHAIN) {
EMIT(" /* CHAIN/COMMON — not supported in compiled mode */\n");
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
if (xstmt == XSTMT_ENVIRON || xstmt == XSTMT_ERDEV ||
xstmt == XSTMT_IOCTL || xstmt == XSTMT_LCOPY ||
xstmt == XSTMT_CALLS || xstmt == XSTMT_COM ||
xstmt == XSTMT_RESET || xstmt == XSTMT_DATE ||
xstmt == XSTMT_TIME || xstmt == XSTMT_PMAP) {
/* Minor statements — skip args */
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
/* Fallback */
EMIT(" /* unhandled xstmt 0x%02x */\n", xstmt);
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
/* DATA — skip (collected at analysis time) */
if (tok == TOK_DATA) {
while (*tp && *tp != ':') tp++;
return;
}
/* READ */
if (tok == TOK_READ) {
advance();
while (cur() && cur() != ':' && cur() != 0) {
skip_spaces();
if (is_letter(cur())) {
char name[2];
gw_valtype_t type = parse_var(name);
if (type == VT_STR) {
EMIT(" gw_str_free(&");
emit_varname(name, type);
EMIT(");\n");
EMIT(" ");
emit_varname(name, type);
EMIT(" = gw_str_from_cstr(gwrt_data_read());\n");
} else {
EMIT(" ");
emit_varname(name, type);
EMIT(" = (%s)atof(gwrt_data_read());\n", c_type(type));
}
}
skip_spaces();
if (cur() == ',') advance();
else break;
}
return;
}
/* RESTORE */
if (tok == TOK_RESTORE) {
advance();
skip_spaces();
if (is_const(cur())) {
uint16_t line = read_int();
/* Find data index for this line */
EMIT(" gwrt_data_restore(data_line_%u);\n", line);
} else {
EMIT(" gwrt_data_restore(0);\n");
}
return;
}
/* LET (explicit) */
if (tok == TOK_LET) {
advance();
emit_assignment();
return;
}
/* CLS */
if (tok == TOK_CLS) {
advance();
EMIT(" if (gw_hal) gw_hal->cls();\n");
return;
}
/* MID$ assignment: MID$(var$, start [,len]) = expr */
if (tok == TOK_PREFIX_FF && tp[1] == FUNC_MID) {
EMIT(" /* MID$ assignment — not yet compiled */\n");
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
/* Implicit assignment (variable at start of statement) */
if (is_letter(tok)) {
emit_assignment();
return;
}
/* Skip unknown tokens */
EMIT(" /* skip tok 0x%02x */\n", tok);
tp++;
}
/* ---- Main code generation ---- */
void codegen_emit(FILE *f, analysis_t *a)
{
out = f;
ana = a;
ret_label_counter = 0;
for_label_counter = 0;
for_stack_sp = 0;
/* Header */
EMIT("/* Generated by gwbasic-compile */\n");
EMIT("#include \"gwrt.h\"\n");
EMIT("#include <math.h>\n");
EMIT("#include <stdlib.h>\n");
EMIT("#include <string.h>\n");
EMIT("#include <time.h>\n\n");
/* Variable declarations */
for (int i = 0; i < a->var_count; i++) {
EMIT("static %s ", c_type(a->vars[i].type));
emit_varname(a->vars[i].name, a->vars[i].type);
if (a->vars[i].type == VT_STR)
EMIT(" = {0, NULL}");
else
EMIT(" = 0");
EMIT(";\n");
}
EMIT("\n");
/* DATA pool */
if (a->data_count > 0) {
EMIT("static const char *_data_pool[] = {\n");
for (int i = 0; i < a->data_count; i++) {
EMIT(" \"");
for (const char *p = a->data_pool[i]; *p; p++) {
if (*p == '"' || *p == '\\') EMIT("\\");
EMIT("%c", *p);
}
EMIT("\",\n");
}
EMIT(" NULL\n};\n");
/* Data line map (for RESTORE n) */
for (int i = 0; i < a->data_line_count; i++)
EMIT("static const int data_line_%d = %d;\n",
a->data_line_map[i][0], a->data_line_map[i][1]);
EMIT("\n");
}
/* Main function */
EMIT("int main(int argc, char **argv) {\n");
EMIT(" (void)argc; (void)argv;\n");
EMIT(" gwrt_init();\n");
if (a->data_count > 0)
EMIT(" gwrt_data_set(_data_pool, NULL, 0);\n");
EMIT("\n");
/* Emit code for each program line */
for (program_line_t *line = gw.prog_head; line; line = line->next) {
/* Label (always emit for targets, comment for others) */
if (analysis_is_target(a, line->num))
EMIT("L_%u:\n", line->num);
else
EMIT("/* %u */ ", line->num);
EMIT(" gwrt_check_line(%u);\n", line->num);
/* Walk statements on this line */
tp = line->tokens;
while (*tp) {
skip_spaces();
if (*tp == ':') { tp++; continue; }
if (*tp == 0) break;
emit_stmt();
}
}
/* Implicit END at bottom */
EMIT(" gwrt_shutdown();\n");
EMIT(" return 0;\n");
EMIT("}\n");
}