fixed a bug with returning

11 files changed, 195 insertions, 22 deletions

diff --git a/arr.c b/arr.c
index 92f0d62..16584f1 100644
--- a/arr.c
+++ b/arr.c
@@ -186,7 +186,7 @@ You shouldn't rely on this, though, e.g. by doing
 #define arr_last(arr) arr_last_((void *)(arr), sizeof *(arr))
 /* one past last, or NULL if empty */
 #define arr_end(arr) arr_end_((void *)(arr), sizeof *(arr))
-#define arr_foreach(arr, type, var) for (type *var = arr, *join(var,_foreach_end) = arr_end(arr); var < join(var,_foreach_end); ++var) /* NOTE: < is useful here because currently it's possible for var_foreach_end to be NULL but var could start out not null */
+#define arr_foreach(arr, type, var) for (type *var = arr, *JOIN(var,_foreach_end) = arr_end(arr); var < JOIN(var,_foreach_end); ++var) /* NOTE: < is useful here because currently it's possible for var_foreach_end to be NULL but var could start out not null */
 #define arr_remove_last(arr) arr_remove_last_((void **)(arr)), (void)sizeof **(arr)
 #define arr_remove_lasta(arr, a) arr_remove_lasta_((void **)(arr), sizeof **(arr), (a))
 #define arr_copya(out, in, a) do { assert(sizeof *(in) == sizeof **(out)); arr_copya_((void **)(out), (in), sizeof **(out), (a)); } while(0)
diff --git a/binfile.c b/binfile.c
index 7f58736..2df96e2 100644
--- a/binfile.c
+++ b/binfile.c
@@ -15,6 +15,7 @@ static inline void write_u8(FILE *fp, U8 u8) {
 		col = 0;
 		printf("\n");
 	}
+	fflush(stdout);
 #endif
 }
 
diff --git a/cgen.c b/cgen.c
index fd5b1a5..b5282e1 100644
--- a/cgen.c
+++ b/cgen.c
@@ -1819,10 +1819,13 @@ static bool cgen_decl(CGenerator *g, Declaration *d) {
 	return true;
 }
 
-/* does NOT call cgen_expr_pre for ret. */
 static bool cgen_ret(CGenerator *g, Expression *ret) {
 	assert((g->fn->ret_type.kind == TYPE_VOID) == (ret == NULL));
-	if (ret) assert(type_eq(&g->fn->ret_type, &ret->type));
+	if (ret) {
+		assert(type_eq(&g->fn->ret_type, &ret->type));
+		if (!cgen_expr_pre(g, ret))
+			return false;
+	}
 	if (!ret) {
 		cgen_write(g, "return");
 	} else if (cgen_uses_ptr(&g->fn->ret_type)) {
@@ -1835,7 +1838,6 @@ static bool cgen_ret(CGenerator *g, Expression *ret) {
 		cgen_write(g, " return");
 	} else {
 		cgen_write(g, "return ");
-			
 		if (!cgen_expr(g, ret)) return false;
 	}
 	cgen_write(g, ";");
@@ -1862,10 +1864,6 @@ static bool cgen_stmt(CGenerator *g, Statement *s) {
 		break;
 	case STMT_RET: {
 		unsigned has_expr = s->ret.flags & RET_HAS_EXPR;
-		if (has_expr) {
-			if (!cgen_expr_pre(g, &s->ret.expr))
-				return false;
-		}
 		if (!cgen_ret(g, has_expr ? &s->ret.expr : NULL))
 			return false;
 	} break;
diff --git a/err.c b/err.c
index 6d57cdc..1ca103e 100644
--- a/err.c
+++ b/err.c
@@ -55,6 +55,8 @@ static void err_vfprint(const char *fmt, va_list args) {
 }
 
 static void err_print_header_(Location where) {
+	if (!where.ctx)
+		err_fprint("Error (no location available):\n");
 #if ERR_EMACS
 	err_fprint("%s:%lu: " TEXT_ERROR("error") ":\n", where.ctx->filename, (unsigned long)where.line);
 #else
@@ -63,6 +65,8 @@ static void err_print_header_(Location where) {
 }
 
 static void info_print_header_(Location where) {
+	if (!where.ctx)
+		err_fprint("Info (no location available):\n");
 #if ERR_EMACS
 	err_fprint("%s:%lu: " TEXT_INFO("info") ":\n", where.ctx->filename, (unsigned long)where.line);
 #else
@@ -71,6 +75,8 @@ static void info_print_header_(Location where) {
 }
 
 static void warn_print_header_(Location where) {
+	if (!where.ctx)
+		err_fprint("Warning (no location available):\n");
 #if ERR_EMACS
 	err_fprint("%s:%lu: " TEXT_WARN("warning") ":\n", where.ctx->filename, (unsigned long)where.line);
 #else
diff --git a/location.c b/location.c
index c5db626..481c033 100644
--- a/location.c
+++ b/location.c
@@ -8,8 +8,14 @@ static bool location_after(Location a, Location b) { /* a is after b? */
 	return a.pos > b.pos;
 }
 
+static Location const LOCATION_NONE = {0};
+
 /* for debugging */
 static void fprint_location(FILE *out, Location location) {
+	if (!location.ctx) {
+		fprintf(out, "No location available.");
+		return;
+	}
 	char *str = location.ctx->str + location.pos;
 	char *newline = strchr(str, '\n');
 	if (newline) *newline = 0;
diff --git a/main.c b/main.c
index 215bbeb..7b91cea 100644
--- a/main.c
+++ b/main.c
@@ -122,10 +122,12 @@ int main(int argc, char **argv) {
 	evalr_create(&ev, &tr, &main_allocr);
 	typer_create(&tr, &ev, &main_allocr);
 	tr.exptr = &exptr;
-
+	
 #ifdef TOC_DEBUG
 	FILE *out_pkg = fopen("out.top", "wb");
 	exptr_create(&exptr, out_pkg);
+	exptr.export_locations = false;
+	
 #endif
 	if (!block_enter(NULL, f.stmts, SCOPE_CHECK_REDECL)) /* enter global scope */
 		return false;
@@ -136,6 +138,15 @@ int main(int argc, char **argv) {
 		return EXIT_FAILURE;
 	}
 #ifdef TOC_DEBUG
+	if (!exptr_finish(&exptr)) {
+		fclose(out_pkg);
+		err_fprint(TEXT_IMPORTANT("Errors occured while exporting things.\n"));
+		return EXIT_FAILURE;
+	}
+	fclose(out_pkg);
+#endif
+#ifdef TOC_DEBUG
+	printf("\n\n");	
 	fprint_parsed_file(stdout, &f);
 #endif
 	FILE *out = fopen(out_filename, "w");
@@ -158,9 +169,6 @@ int main(int argc, char **argv) {
 	evalr_free(&ev);
 	
 	fclose(out);
-#ifdef TOC_DEBUG
-	fclose(out_pkg);
-#endif
 	idents_free(&file_idents);
 	return 0;
 }
diff --git a/package.c b/package.c
index 0090ab5..3dfaab6 100644
--- a/package.c
+++ b/package.c
@@ -3,11 +3,17 @@
   This file is part of toc. toc is distributed under version 3 of the GNU General Public License, without any warranty whatsoever.
   You should have received a copy of the GNU General Public License along with toc. If not, see <https://www.gnu.org/licenses/>.
 */
+static bool export_decl(Exporter *ex, Declaration *d);
+static bool export_block(Exporter *ex, Block *b);
+
+
 static void exptr_create(Exporter *exptr, FILE *out) {
 	exptr->out = out;
 	exptr->export_locations = true;
+	exptr->exported_fns = NULL;
 }
 
+
 static void export_u8(Exporter *ex, U8 u8) {
 	write_u8(ex->out, u8);
 }
@@ -63,16 +69,33 @@ static void export_ident(Exporter *ex, Identifier i) {
 	}
 }
 
+static bool export_len8(Exporter *ex, size_t len, const char *for_, Location where) {
+	if (len > U8_MAX) {
+		err_print(where, "Too many %s (the maximum is " STRINGIFY(U8_MAX) ").", for_);
+		return false;
+	}
+	export_u8(ex, (U8)len);
+	return true;
+}
 
 static bool export_len16(Exporter *ex, size_t len, const char *for_, Location where) {
-	if (len > 65535) {
-		err_print(where, "Too many %s (the maximum is 65535).", for_);
+	if (len > U16_MAX) {
+		err_print(where, "Too many %s (the maximum is " STRINGIFY(U16_MAX) ").", for_);
 		return false;
 	}
 	export_u16(ex, (U16)len);
 	return true;
 }
 
+static bool export_len32(Exporter *ex, size_t len, const char *for_, Location where) {
+	if (len > U32_MAX) {
+		err_print(where, "Too many %s (the maximum is " STRINGIFY(U32_MAX) ").", for_);
+		return false;
+	}
+	export_u32(ex, (U32)len);
+	return true;
+}
+
 static bool export_type(Exporter *ex, Type *type, Location where) {
 	assert(type->flags & TYPE_IS_RESOLVED);
 	export_u8(ex, (U8)type->kind);
@@ -98,6 +121,18 @@ static bool export_type(Exporter *ex, Type *type, Location where) {
 		if (!export_type(ex, type->arr.of, where))
 			return false;
 		break;
+	case TYPE_FN:
+		if (!export_len16(ex, arr_len(type->fn.types), "types in a function type", where))
+			return false;
+		arr_foreach(type->fn.types, Type, sub)
+			if (!export_type(ex, sub, where))
+				return false;
+		export_u8(ex, type->fn.constness != NULL);
+		/* [implied] if (type->fn.constness) */
+		assert(sizeof(Constness) == 1); /* future-proofing */
+		arr_foreach(type->fn.constness, Constness, c)
+			export_u8(ex, *c);
+		break;
 	case TYPE_EXPR:
 		assert(0);
 		return false;
@@ -105,6 +140,20 @@ static bool export_type(Exporter *ex, Type *type, Location where) {
 	return true;
 }
 
+static bool export_fn_ptr(Exporter *ex, FnExpr *f, Location where) {
+	if (f->export.id == 0) {
+		FnWithLocation *floc = arr_add(&ex->exported_fns);
+		floc->fn = f;
+		floc->where = where;
+		if (arr_len(ex->exported_fns) > U32_MAX) {
+			err_print(where, "Too many exported functions (the maximum is " STRINGIFY(U32_MAX) ").");
+		}
+		f->export.id = (U32)arr_len(ex->exported_fns);
+	}
+	export_u32(ex, f->export.id);
+	return true;
+}
+
 static bool export_val(Exporter *ex, Value val, Type *type, Location where);
 static bool export_val_ptr(Exporter *ex, void *val, Type *type, Location where) {
 	switch (type->kind) {
@@ -168,6 +217,10 @@ static bool export_val_ptr(Exporter *ex, void *val, Type *type, Location where)
 			ptr += item_size;
 		}
 	} break;
+	case TYPE_FN:
+		if (!export_fn_ptr(ex, *(FnExpr **)val, where))
+			return false;
+		break;
 	case TYPE_UNKNOWN:
 	case TYPE_EXPR:
 		assert(0);
@@ -237,6 +290,22 @@ static bool export_expr(Exporter *ex, Expression *e) {
 		if (!export_type(ex, &e->typeval, e->where))
 			return false;
 		break;
+	case EXPR_FN:
+		if (!export_fn_ptr(ex, e->fn, e->where))
+			return false;
+		break;
+	case EXPR_BLOCK:
+		if (!export_block(ex, &e->block))
+			return false;
+		break;
+	case EXPR_NEW:
+		if (!export_type(ex, &e->new.type, e->where))
+			return false;
+		export_u8(ex, e->new.n != NULL);
+		if (e->new.n)
+			if (!export_expr(ex, e->new.n))
+				return false;
+		break;
 	case EXPR_DSIZEOF:
 	case EXPR_DALIGNOF:
 		assert(0);
@@ -287,3 +356,69 @@ static bool export_decl(Exporter *ex, Declaration *d) {
 	}
 	return true;
 }
+
+static bool export_stmt(Exporter *ex, Statement *s) {
+	export_u8(ex, (U8)s->kind);
+	switch (s->kind) {
+	case STMT_EXPR:
+		if (!export_expr(ex, &s->expr))
+			return false;
+		break;
+	case STMT_DECL:
+		if (!export_decl(ex, &s->decl))
+			return false;
+		break;
+	case STMT_RET:
+		assert(sizeof s->ret.flags == 1);
+		export_u8(ex, (U8)s->ret.flags);
+		if (s->ret.flags & RET_HAS_EXPR)
+			if (!export_expr(ex, &s->ret.expr))
+				return false;
+		break;
+	}
+	return true;
+}
+
+static bool export_block(Exporter *ex, Block *b) {
+	export_location(ex, b->start);
+	export_location(ex, b->end);
+	if (!export_len32(ex, arr_len(b->stmts), "statements in a block", b->start))
+		return false;
+	arr_foreach(b->stmts, Statement, s) {
+		if (!export_stmt(ex, s))
+			return false;
+	}
+	export_u8(ex, b->ret_expr != NULL);
+	if (b->ret_expr)
+		if (!export_expr(ex, b->ret_expr))
+			return false;
+	return true;
+}
+
+static bool export_fn(Exporter *ex, FnExpr *f, Location where) {
+	if (!export_len16(ex, arr_len(f->params), "parameters in a function", where))
+		return false;
+	arr_foreach(f->params, Declaration, param)
+		if (!export_decl(ex, param))
+			return false;
+	if (!export_len8(ex, arr_len(f->ret_decls), "return declarations", where))
+		return false;
+	arr_foreach(f->ret_decls, Declaration, ret_decl)
+		if (!export_decl(ex, ret_decl))
+			return false;
+	/* no need to export the return type */
+	if (!export_block(ex, &f->body))
+		return false;
+	return true;
+}
+
+/* does NOT close the file */
+static bool exptr_finish(Exporter *ex) {
+	if (!export_len32(ex, arr_len(ex->exported_fns), "exported functions", LOCATION_NONE))
+		return false;
+	arr_foreach(ex->exported_fns, FnWithLocation, f) {
+		if (!export_fn(ex, f->fn, f->where))
+			return false;
+	}
+	return true;
+}
diff --git a/parse.c b/parse.c
index 78341fb..d8765de 100644
--- a/parse.c
+++ b/parse.c
@@ -1021,7 +1021,7 @@ static bool parse_expr(Parser *p, Expression *e, Token *end) {
 			e->kind = EXPR_FN;
 			if (!parse_fn_expr(p, e->fn = parser_malloc(p, sizeof *e->fn)))
 				return false;
-			
+			e->fn->export.id = 0;
 			if (t->token != end) {
 				if (token_is_kw(t->token, KW_LPAREN))
 					tokr_err(t, "Direct function calling in an expression is not supported.\nYou can wrap the function in parentheses.");
diff --git a/test.toc b/test.toc
index fba8ffb..24b6bcf 100644
--- a/test.toc
+++ b/test.toc
@@ -1,2 +1,4 @@
-#export asdf ::= int;
-#export ghjk := #sizeof(asdf);
\ No newline at end of file
+#export main ::= fn() int {
+		{3}
+};
+// #export ghjk := #sizeof(asdf);
\ No newline at end of file
diff --git a/toc.c b/toc.c
index cd19afb..18c79bb 100644
--- a/toc.c
+++ b/toc.c
@@ -31,6 +31,12 @@
 /* forward declarations for debugging */
 static void print_val(Value v, Type *t);
 
+
+/* misc */
+#define JOIN(a,b) a##b
+#define STRINGIFY2(x) #x
+#define STRINGIFY(x) STRINGIFY2(x)
+
 static void fprint_char_literal(FILE *f, char c) {
 	if (isprint(c))
 		fprintf(f, "'%c'", c);
@@ -39,6 +45,7 @@ static void fprint_char_literal(FILE *f, char c) {
 }
 
 
+
 /* utilities */
 #include "allocator.c"
 #include "arr.c"
diff --git a/types.h b/types.h
index d2d6757..e15e550 100644
--- a/types.h
+++ b/types.h
@@ -69,13 +69,11 @@ typedef double F64;
 
 typedef U32 IdentID; /* identifier ID for cgen (anonymous variables). not to be confused with IdentTree.id */
 
-#define join(a,b) a##b
-
 /* for keeping track of whence something came */
 #ifdef TOC_DEBUG
 #define SOURCE_LOCATION char *src_file; int src_line;
 #define SOURCE_LOCATION_PARAMS char *src_file, int src_line,
-#define DEBUG_UNDERSCORE(x) join(x,_)
+#define DEBUG_UNDERSCORE(x) JOIN(x,_)
 #else
 #define SOURCE_LOCATION
 #define SOURCE_LOCATION_PARAMS
@@ -547,6 +545,7 @@ typedef struct EachExpr {
 	};
 } EachExpr;
 
+
 typedef struct FnExpr {
     struct Declaration *params; /* declarations of the parameters to this function */
     struct Declaration *ret_decls; /* array of decls, if this has named return values. otherwise, NULL */
@@ -557,6 +556,11 @@ typedef struct FnExpr {
 							if the ith semi-constant parameter is constant.
 						 */
 	struct {
+		U32 id; /* (index of function in ex->exported_fns) + 1, 
+				   or 0 if this function has not been
+				   added to the exporting array yet */
+	} export;
+	struct {
 		/* if name = NULL, this is an anonymous function, and id will be the ID of the fn. */
 		Identifier name;
 	    IdentID id;
@@ -669,7 +673,7 @@ enum {
 	  DECL_EXPORT = 0x0200
 };
 
-typedef U32 DeclFlags;
+typedef U16 DeclFlags;
 
 /* OPTIM: Instead of using dynamic arrays, do two passes. */
 typedef struct Declaration {
@@ -691,7 +695,7 @@ enum {
 	  RET_HAS_EXPR = 0x01,
 };
 typedef struct Return {
-	U16 flags;
+	U8 flags; /* if this changes, go to package.c */
 	Expression expr;
 } Return;
 
@@ -745,9 +749,15 @@ typedef struct Typer {
 	FnExpr *fn; /* the function we're currently parsing. */
 } Typer;
 
+typedef struct {
+	FnExpr *fn;
+	Location where;
+} FnWithLocation;
+
 typedef struct Exporter {
 	FILE *out; /* .top (toc package) to output to */
 	bool export_locations;
+    FnWithLocation *exported_fns;
 } Exporter;
 
 typedef struct CGenerator {