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Compiler: string comparison, ON ERROR GOTO, graphics delegation — 48/72

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String comparison: detect VT_STR left operand in relationals (>, <, =,
<=, >=, <>), re-emit as string atom, and use strcmp-based comparison
via GCC statement expression. Unlocks bubble_sort.

ON ERROR GOTO: add setjmp guard in generated main() that dispatches
to all GOTO target labels on error. Partial error_handler support.

Graphics/sound/file I/O extended statements: delegate to runtime via
token embedding with variable sync (same technique as PRINT USING and
DEF FN). Includes CIRCLE, DRAW, PAINT, PLAY, VIEW, WINDOW, PALETTE,
FIELD, LSET, RSET, PUT, GET. Fixed FE-prefix position tracking.

FRE("") GC: sync string variables to interpreter table before GC so
the collector can find live strings in compiled programs.

Division semantics: / always float (cast to double).

48/72 tests pass. New: bubble_sort, invoice. play_music/play_scale
restored after FE-prefix fix.
This commit is contained in:
Eremey Valetov
2026-03-29 16:11:21 -04:00
parent 5546ba42fe
commit 9d0eb579bc
1 changed files with 119 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/codegen.c
+119 -17
View File
@@ -166,10 +166,12 @@ static const char *binop_c(uint8_t tok)
}
}
/* Forward declarations for buffered expression emission */
/* Forward declarations */
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);
static void emit_str_atom(void);
static gw_valtype_t peek_expr_type(void);
/* Emit a numeric atom */
static void emit_atom(void)
@@ -357,7 +359,24 @@ static void emit_atom(void)
if (cur() == '(') { advance(); emit_num_expr(); if (cur() == ')') advance(); }
return;
case FUNC_FRE:
EMIT("(strpool_gc(), (float)strpool_free())");
/* In compiled code, GC can't find C-static variables.
* Sync vars to interpreter table before GC for FRE(""). */
if (cur() == '(' && tp[1] == '"') {
EMIT("({");
for (int vi = 0; vi < ana->var_count; vi++) {
var_info_t *v = &ana->vars[vi];
if (v->type != VT_STR) continue;
if (v->name[1])
EMIT("gw_var_find_or_create(\"%c%c\",%d)->val.sval=", v->name[0], v->name[1], v->type);
else
EMIT("gw_var_find_or_create(\"%c\",%d)->val.sval=", v->name[0], v->type);
emit_varname(v->name, v->type);
EMIT(";");
}
EMIT(" strpool_gc(); (float)strpool_free();})");
} else {
EMIT("((float)strpool_free())");
}
if (cur() == '(') {
advance();
while (cur() && cur() != ')') tp++;
@@ -604,6 +623,9 @@ 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 */
/* Peek at atom type (for string comparison detection) */
gw_valtype_t left_type = peek_expr_type();
uint8_t *left_start = tp; /* save position for string re-emit */
char *left = emit_to_buf(emit_atom_wrapper, 0);
for (;;) {
@@ -622,6 +644,40 @@ static void emit_num_prec(int min_prec)
else if (op == TOK_EQ && cur() == TOK_LT) { advance(); cop = "<="; }
else if (op == TOK_EQ && cur() == TOK_GT) { advance(); cop = ">="; }
/* For string comparisons, emit strcmp-based code */
bool is_relational = cop || op == TOK_GT || op == TOK_LT || op == TOK_EQ;
if (is_relational && left_type == VT_STR) {
/* Re-emit left as string (it was emitted as numeric atom) */
uint8_t *save_tp = tp;
tp = left_start;
char *left_str;
{ FILE *orig = out; char *buf = NULL; size_t sz = 0;
out = open_memstream(&buf, &sz);
emit_str_atom();
fclose(out); out = orig; left_str = buf; }
tp = save_tp;
/* Buffer right as string expression */
char *right_str;
{ FILE *orig = out; char *buf = NULL; size_t sz = 0;
out = open_memstream(&buf, &sz);
emit_str_atom();
fclose(out); out = orig; right_str = buf; }
const char *cmpop = cop ? cop : binop_c(op);
char *combined = NULL; size_t csz = 0;
FILE *cm = open_memstream(&combined, &csz);
fprintf(cm, "({gw_string_t _sl=%s; gw_string_t _sr=%s;"
" char *_cl=gw_str_to_cstr(&_sl); char *_cr=gw_str_to_cstr(&_sr);"
" int _cmp=strcmp(_cl,_cr); free(_cl); free(_cr);"
" gw_str_free(&_sl); gw_str_free(&_sr);"
" (_cmp %s 0) ? -1 : 0;})",
left_str, right_str, cmpop);
fclose(cm);
free(left); free(left_str); free(right_str);
left = combined;
left_type = VT_INT;
continue;
}
char *right = emit_to_buf(emit_prec_wrapper, prec + 1);
char *combined = NULL;
@@ -1765,6 +1821,7 @@ static void emit_stmt(void)
/* Extended statements (0xFE prefix) */
if (tok == TOK_PREFIX_FE) {
uint8_t *fe_start = tp; /* save position of 0xFE prefix */
uint8_t xstmt = tp[1];
tp += 2;
skip_spaces();
@@ -1788,24 +1845,56 @@ static void emit_stmt(void)
while (cur() && cur() != ':' && cur() != 0) tp++;
return;
}
/* Graphics, sound, view/window/palette, file I/O extended stmts:
* embed tokens and delegate to runtime interpreter */
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_PAINT || xstmt == XSTMT_PLAY ||
xstmt == XSTMT_VIEW || xstmt == XSTMT_WINDOW ||
xstmt == XSTMT_PALETTE ||
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++;
uint8_t *stmt_start = fe_start;
/* Find end of statement, skipping strings and constants */
program_line_t *cur_pl = NULL;
for (program_line_t *pl = gw.prog_head; pl; pl = pl->next) {
if (tp >= pl->tokens && tp <= pl->tokens + pl->len) {
cur_pl = pl; break;
}
}
uint8_t *line_end = cur_pl ? cur_pl->tokens + cur_pl->len : tp + 256;
while (tp < line_end) {
if (*tp == '"') { tp++; while (tp < line_end && *tp != '"') tp++; if (tp < line_end) tp++; continue; }
if (*tp == TOK_CONST_SNG) { tp += 5; continue; }
if (*tp == TOK_CONST_DBL) { tp += 9; continue; }
if (*tp == ':' || *tp == 0) break;
tp++;
}
int slen = (int)(tp - stmt_start);
/* Sync variables and call interpreter */
EMIT(" {\n");
for (int vi = 0; vi < ana->var_count; vi++) {
var_info_t *v = &ana->vars[vi];
if (v->name[1])
EMIT(" gw_var_find_or_create(\"%c%c\", %d)->val = ", v->name[0], v->name[1], v->type);
else
EMIT(" gw_var_find_or_create(\"%c\", %d)->val = ", v->name[0], 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 _xs[] = {");
for (int i = 0; i < slen; i++)
EMIT("%s%u", i ? "," : "", stmt_start[i]);
EMIT(",0};\n");
EMIT(" gw.text_ptr = (uint8_t *)_xs;\n");
EMIT(" gw_exec_stmt();\n }\n");
return;
}
if (xstmt == XSTMT_COMMON || xstmt == XSTMT_CHAIN) {
@@ -2001,6 +2090,19 @@ void codegen_emit(FILE *f, analysis_t *a)
EMIT(" gwrt_data_set(_data_pool, NULL, 0);\n");
EMIT("\n");
/* ON ERROR GOTO handler via setjmp */
EMIT(" { int _err = setjmp(gw_error_jmp);\n");
EMIT(" if (_err) {\n");
EMIT(" if (gwrt_error_target) {\n");
EMIT(" int _tgt = gwrt_error_target;\n");
/* Dispatch to all possible ON ERROR GOTO targets */
for (int i = 0; i < a->goto_count; i++)
EMIT(" if (_tgt == %u) goto L_%u;\n",
a->goto_targets[i], a->goto_targets[i]);
EMIT(" }\n");
EMIT(" gwrt_shutdown(); return 1;\n");
EMIT(" }\n }\n\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) */