improved FnExpr structure

5 files changed, 43 insertions, 49 deletions

diff --git a/cgen.c b/cgen.c
index 2bb53bf..4351466 100644
--- a/cgen.c
+++ b/cgen.c
@@ -122,9 +122,9 @@ static void cgen_defs_decl(CGenerator *g, Declaration *d);
 	case EXPR_FN: {														\
 		FnExpr *fn = e->fn;												\
 		if (fn_has_instances(fn)) {										\
-			Instance **data = fn->instances.data;						\
-			for (U64 i = 0; i < fn->instances.cap; ++i) {				\
-				if (fn->instances.occupied[i]) {						\
+			Instance **data = fn->instances->data;						\
+			for (U64 i = 0; i < fn->instances->cap; ++i) {				\
+				if (fn->instances->occupied[i]) {						\
 					cgen_recurse_subexprs_fn_simple(((*data)->fn), decl_f, block_f); \
 				}														\
 				++data;													\
@@ -432,15 +432,14 @@ static bool cgen_should_gen_fn(FnExpr *f) {
 	}
 }
 
-static void cgen_full_fn_name(CGenerator *g, FnExpr *f, U64 instance) {
+static void cgen_full_fn_name(CGenerator *g, FnExpr *f) {
 	cgen_fn_name(g, f);
-	if (instance) {
-		cgen_fn_instance_number(g, instance);
+	if (f->instance_id) {
+		cgen_fn_instance_number(g, f->instance_id);
 	}
 }
 
-static void cgen_fn_params(CGenerator *g, FnExpr *f, U64 instance, U64 which_are_const) {
-	(void)instance; /* not needed atm */
+static void cgen_fn_params(CGenerator *g, FnExpr *f, U64 which_are_const) {
 	bool out_param = cgen_uses_ptr(&f->ret_type);
 	cgen_write(g, "(");
 	int semi_const_idx = 0;
@@ -527,8 +526,8 @@ static inline void cgen_arg(CGenerator *g, Expression *arg) {
 	}
 }
 
-/* unless f has const/semi-const args, instance and which_are_const can be set to 0 */
-static void cgen_fn_header(CGenerator *g, FnExpr *f, U64 instance, U64 which_are_const) {
+/* unless f has const/semi-const args, which_are_const can be set to 0 */
+static void cgen_fn_header(CGenerator *g, FnExpr *f, U64 which_are_const) {
 	assert(!(f->flags & FN_EXPR_FOREIGN));
 	
 	bool out_param = cgen_uses_ptr(&f->ret_type);
@@ -541,8 +540,8 @@ static void cgen_fn_header(CGenerator *g, FnExpr *f, U64 instance, U64 which_are
 		cgen_type_pre(g, &f->ret_type);
 		cgen_write(g, " ");
 	}
-	cgen_full_fn_name(g, f, instance);	
-    cgen_fn_params(g, f, instance, which_are_const);
+	cgen_full_fn_name(g, f);	
+    cgen_fn_params(g, f, which_are_const);
 	if (!out_param) {
 		cgen_type_post(g, &f->ret_type);
 	}
@@ -690,7 +689,7 @@ static void cgen_set_tuple(CGenerator *g, Expression *exprs, Identifier *idents,
 		cgen_expr(g, to->call.fn);
 		
 		if (to->call.instance)
-			cgen_fn_instance_number(g, to->call.instance->c.id);
+			cgen_fn_instance_number(g, to->call.instance->fn->instance_id);
 		cgen_write(g, "(");
 		bool any_args = false;
 		i = 0;
@@ -1039,7 +1038,7 @@ static void cgen_expr_pre(CGenerator *g, Expression *e) {
 			}
 		    cgen_expr(g, e->call.fn);
 			if (e->call.instance) {
-				cgen_fn_instance_number(g, e->call.instance->c.id);
+				cgen_fn_instance_number(g, e->call.instance->fn->instance_id);
 			}
 			cgen_write(g, "(");
 			bool any_args = false;
@@ -1068,7 +1067,7 @@ static void cgen_expr_pre(CGenerator *g, Expression *e) {
 			cgen_write(g, ";"); cgen_nl(g);
 			cgen_expr(g, e->call.fn);
 			if (e->call.instance) {
-				cgen_fn_instance_number(g, e->call.instance->c.id);
+				cgen_fn_instance_number(g, e->call.instance->fn->instance_id);
 			}
 			cgen_write(g, "(");
 			bool any_args = false;
@@ -1452,7 +1451,7 @@ static void cgen_expr(CGenerator *g, Expression *e) {
 			cgen_write(g, "(");
 			cgen_expr(g, e->call.fn);
 			if (e->call.instance) {
-				cgen_fn_instance_number(g, e->call.instance->c.id);
+				cgen_fn_instance_number(g, e->call.instance->fn->instance_id);
 			}
 			cgen_write(g, "(");
 			bool first_arg = true;
@@ -1608,8 +1607,11 @@ static void cgen_zero_value(CGenerator *g, Type *t) {
 	}
 }
 
-/* pass 0 for instance and NULL for compile_time_args if there are no compile time arguments. */
-static void cgen_fn(CGenerator *g, FnExpr *f, U64 instance, Value *compile_time_args) {
+/* pass NULL for compile_time_args if there are no compile time arguments.
+compile_time_args is needed because we can't determine which_are_const
+from just f.
+ */
+static void cgen_fn(CGenerator *g, FnExpr *f, Value *compile_time_args) {
 	if (f->flags & FN_EXPR_FOREIGN)
 		return; /* handled by decls_cgen */
 	/* see also cgen_defs_expr */
@@ -1617,7 +1619,7 @@ static void cgen_fn(CGenerator *g, FnExpr *f, U64 instance, Value *compile_time_
 	U64 which_are_const = compile_time_args ? compile_time_args->u64 : 0;
 	if (!cgen_should_gen_fn(f))
 		return;
-	cgen_fn_header(g, f, instance, which_are_const);
+	cgen_fn_header(g, f, which_are_const);
 	g->fn = f;
 	cgen_write(g, " {");
 	cgen_nl(g);
@@ -1982,17 +1984,17 @@ static void cgen_stmt(CGenerator *g, Statement *s) {
 
 static void cgen_defs_fn(CGenerator *g, FnExpr *f) {
 	if (fn_has_instances(f)) {
-		HashTable *instances = &f->instances;
+		HashTable *instances = f->instances;
 		/* generate each instance */
 		Instance **is = instances->data;
 		for (U64 i = 0; i < instances->cap; ++i) {
 			if (instances->occupied[i]) {
 				/* generate this instance */
-				cgen_fn(g, is[i]->fn, is[i]->c.id, is[i]->val.tuple);
+				cgen_fn(g, is[i]->fn, is[i]->val.tuple);
 			}
 		}
 	} else {
-		cgen_fn(g, f, 0, NULL);
+		cgen_fn(g, f, NULL);
 	}
 }
 
diff --git a/decls_cgen.c b/decls_cgen.c
index 86c4cf9..8ebf051 100644
--- a/decls_cgen.c
+++ b/decls_cgen.c
@@ -37,9 +37,9 @@ static void cgen_decls_type(CGenerator *g, Type *type) {
 	cgen_recurse_subtypes(cgen_decls_type, g, type);
 }
 
-static void cgen_single_fn_decl(CGenerator *g, FnExpr *f, U64 instance, U64 which_are_const) {
+static void cgen_single_fn_decl(CGenerator *g, FnExpr *f, U64 which_are_const) {
 	if (cgen_should_gen_fn(f)) {
-		cgen_fn_header(g, f, instance, which_are_const);
+		cgen_fn_header(g, f, which_are_const);
 		cgen_write(g, ";");
 		cgen_nl(g);
 	}
@@ -47,13 +47,13 @@ static void cgen_single_fn_decl(CGenerator *g, FnExpr *f, U64 instance, U64 whic
 
 
 static void cgen_decls_fn_instances(CGenerator *g, FnExpr *f) {
-	Instance **data = f->instances.data;
-	for (U64 i = 0; i < f->instances.cap; ++i) {
-		if (f->instances.occupied[i]) {
+	Instance **data = f->instances->data;
+	for (U64 i = 0; i < f->instances->cap; ++i) {
+		if (f->instances->occupied[i]) {
 			if (cgen_should_gen_fn((*data)->fn)) {
 				(*data)->fn->c.name = f->c.name;
 				(*data)->fn->c.id = f->c.id;
-				cgen_single_fn_decl(g, (*data)->fn, (*data)->c.id, (*data)->val.tuple[0].u64);
+				cgen_single_fn_decl(g, (*data)->fn, (*data)->val.tuple[0].u64);
 				cgen_write(g, ";");
 				cgen_nl(g);
 			}
@@ -170,7 +170,7 @@ static void cgen_fn_decl(CGenerator *g, FnExpr *f, Type *t) {
 	if (fn_has_instances(f)) {
 		cgen_decls_fn_instances(g, f);
 	} else {
-		cgen_single_fn_decl(g, f, 0, 0);
+		cgen_single_fn_decl(g, f, 0);
 	}
 }
 
diff --git a/parse.c b/parse.c
index b011ed0..f7cdca2 100644
--- a/parse.c
+++ b/parse.c
@@ -950,12 +950,9 @@ static Status parse_decl_list(Parser *p, Declaration **decls, DeclEndKind decl_e
 
 static Status parse_fn_expr(Parser *p, FnExpr *f) {
 	Tokenizer *t = p->tokr;
+	f->instance_id = 0;
 	f->ret_decls = NULL;
-	{
-		/* help types.c */
-		HashTable z = {0};
-		f->instances = z;
-	}
+	f->instances = NULL;
 	/* only called when token is fn */
 	assert(token_is_kw(t->token, KW_FN));
 	++t->token;
diff --git a/types.c b/types.c
index 7b8207f..506dea0 100644
--- a/types.c
+++ b/types.c
@@ -1466,8 +1466,7 @@ static Status types_expr(Typer *tr, Expression *e) {
 			return false;
 		}
 		if (fn_has_any_const_params(e->fn) || fn_type_has_varargs(&e->type.fn)) {
-			HashTable z = {0};
-			e->fn->instances = z;
+			e->fn->instances = typer_calloc(tr, 1, sizeof *e->fn->instances);
 		} else {
 			if (!types_fn(tr, e->fn, &e->type, NULL)) {
 				return false;
@@ -2444,14 +2443,14 @@ static Status types_expr(Typer *tr, Expression *e) {
 				}
 			}
 			bool instance_already_exists;
-			c->instance = instance_table_adda(tr->allocr, &original_fn->instances, table_index, &table_index_type, &instance_already_exists);
+			c->instance = instance_table_adda(tr->allocr, original_fn->instances, table_index, &table_index_type, &instance_already_exists);
 			if (instance_already_exists) {
 				arr_cleara(&table_index_type.tuple, tr->allocr);
 				arr_cleara(&table_index.tuple, tr->allocr);
 			} else {
 				c->instance->fn = fn_copy;
 				/* fix parameter and return types (they were kind of problematic before, because we didn't know about the instance) */
-				c->instance->c.id = original_fn->instances.n; /* let's help cgen out and assign an ID to this */
+			    fn_copy->instance_id = 1+original_fn->instances->n; /* let's help cgen out and assign a non-zero ID to this */
 				/* type this instance */
 				
 				/* if anything happens, make sure we let the user know that this happened while generating a fn */
diff --git a/types.h b/types.h
index 9d55b84..5540d16 100644
--- a/types.h
+++ b/types.h
@@ -684,6 +684,7 @@ typedef struct FnExpr {
 		struct {
 			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 */
+			U64 instance_id;
 			Type ret_type;	
 			Block body;
 		};
@@ -701,11 +702,11 @@ typedef struct FnExpr {
 			void (*fn_ptr)();
 		} foreign;
 	};
-	HashTable instances; /* for fns with constant parameters. the key is a tuple where
-							the first element is a u64 value whose ith bit (1<<i) is 1
-							if the ith semi-constant parameter is constant.
-							cgen relies on this being here even for foreign fns.
-						 */
+	HashTable *instances; /* for fns with constant parameters. the key is a tuple where
+							 the first element is a u64 value whose ith bit (1<<i) is 1
+							 if the ith semi-constant parameter is constant.
+							 cgen relies on this being here even for foreign fns.
+						  */
 	struct {
 		/* if name = NULL, this is an anonymous function, and id will be the ID of the fn. */
 		Identifier name;
@@ -717,12 +718,7 @@ typedef struct FnExpr {
 typedef struct Instance {
 	Value val; /* key into hash table */
 	union {
-		struct {
-			FnExpr *fn; /* the typed function */
-			struct {
-				U64 id;
-			} c;
-		};
+		FnExpr *fn; /* the typed function */
 		StructDef struc;
 	};
 } Instance;