lang: codegen: implement return generation

lang/codegen/block.c

@@ -40,6 +40,24 @@ static struct code_generator_result gen_var_declaration(
 	return CODEGEN_RESULT_OK(CODEGEN_R_REPEAT_NODE);
 }
 
+static struct code_generator_result gen_return(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct ivy_ast_node *node, size_t depth)
+{
+	struct block_codegen_state *block = (struct block_codegen_state *)state;
+	struct mie_builder *builder = gen->c_builder;
+	struct mie_func *current = mie_builder_get_current_func(builder);
+
+	enum ivy_status status = IVY_OK;
+
+	if (status != IVY_OK) {
+		return CODEGEN_RESULT_ERR(status);
+	}
+
+	codegen_push_generator(gen, CODE_GENERATOR_RETURN, 0, NULL);
+	return CODEGEN_RESULT_OK(CODEGEN_R_REPEAT_NODE);
+}
+
 static enum ivy_status state_init(
 	struct ivy_codegen *gen, struct code_generator_state *state,
 	uintptr_t argv, void *argp)
@@ -62,6 +80,7 @@ struct code_generator block_generator = {
 	.g_state_fini = state_fini,
 	.g_node_generators = {
 		NODE_CODEGEN(VAR, gen_var_declaration),
+		NODE_CODEGEN(RETURN, gen_return),
 	},
 	.g_expr_generator = gen_expr,
 };

lang/codegen/codegen.h

@@ -44,6 +44,7 @@ enum code_generator_type {
 	CODE_GENERATOR_MSG,
 	CODE_GENERATOR_FSTRING,
 	CODE_GENERATOR_LAMBDA,
+	CODE_GENERATOR_RETURN,
 };
 
 enum code_generator_scope_type {

lang/codegen/generator.c

@@ -9,6 +9,7 @@ extern const struct code_generator var_generator;
 extern const struct code_generator msg_generator;
 extern const struct code_generator fstring_generator;
 extern const struct code_generator lambda_generator;
+extern const struct code_generator return_generator;
 
 static const struct code_generator *code_generators[] = {
 	[CODE_GENERATOR_UNIT] = &unit_generator,
@@ -18,6 +19,7 @@ static const struct code_generator *code_generators[] = {
 	[CODE_GENERATOR_MSG] = &msg_generator,
 	[CODE_GENERATOR_FSTRING] = &fstring_generator,
 	[CODE_GENERATOR_LAMBDA] = &lambda_generator,
+	[CODE_GENERATOR_RETURN] = &return_generator,
 };
 static const size_t nr_code_generators
 	= sizeof code_generators / sizeof code_generators[0];

lang/codegen/return.c

@@ -0,0 +1,88 @@
+#include "../debug.h"
+#include "codegen.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct return_codegen_state {
+	struct code_generator_state s_base;
+	unsigned int s_prev_node;
+	struct mie_value *s_value;
+};
+
+static struct code_generator_result gen_return(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct ivy_ast_node *node, size_t depth)
+{
+	struct return_codegen_state *ret = (struct return_codegen_state *)state;
+	if (ret->s_prev_node != 0) {
+		return CODEGEN_RESULT_ERR(IVY_ERR_BAD_SYNTAX);
+	}
+
+	ret->s_prev_node = IVY_AST_RETURN;
+	return CODEGEN_RESULT_OK(0);
+}
+
+static struct code_generator_result gen_value_expr(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct ivy_ast_node *node, size_t depth)
+{
+	struct return_codegen_state *ret = (struct return_codegen_state *)state;
+	if (ret->s_prev_node != IVY_AST_RETURN) {
+		return CODEGEN_RESULT_ERR(IVY_ERR_BAD_SYNTAX);
+	}
+
+	codegen_push_generator(gen, CODE_GENERATOR_EXPR, 0, NULL);
+
+	return CODEGEN_RESULT_OK(CODEGEN_R_REPEAT_NODE);
+}
+
+static enum ivy_status state_init(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	uintptr_t argv, void *argp)
+{
+	debug_printf("codegen: start of return\n");
+	return IVY_OK;
+}
+
+static enum ivy_status state_fini(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct mie_value **result)
+{
+	debug_printf("codegen: end of return\n");
+	struct return_codegen_state *ret = (struct return_codegen_state *)state;
+
+	mie_builder_ret(gen->c_builder, ret->s_value);
+
+	return IVY_OK;
+}
+
+static struct code_generator_result value_received(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct mie_value *value)
+{
+	debug_printf("codegen: return value received\n");
+
+	struct return_codegen_state *ret = (struct return_codegen_state *)state;
+	if (ret->s_value || ret->s_prev_node != IVY_AST_RETURN) {
+		return CODEGEN_RESULT_ERR(IVY_ERR_BAD_SYNTAX);
+	}
+
+	ret->s_value = value;
+	ret->s_prev_node = IVY_AST_EXPR;
+
+	return CODEGEN_RESULT_OK(CODEGEN_R_POP_GENERATOR);
+}
+
+struct code_generator return_generator = {
+	.g_type = CODE_GENERATOR_VAR,
+	.g_state_size = sizeof(struct return_codegen_state),
+	.g_state_init = state_init,
+	.g_state_fini = state_fini,
+	.g_value_received = value_received,
+	.g_expr_generator = gen_value_expr,
+	.g_node_generators = {
+		[IVY_AST_RETURN] = gen_return,
+	},
+};

lang/codegen/unit.c

@@ -183,6 +183,27 @@ static struct code_generator_result gen_var_declaration(
 	return CODEGEN_RESULT_OK(CODEGEN_R_REPEAT_NODE);
 }
 
+static struct code_generator_result gen_return(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct ivy_ast_node *node, size_t depth)
+{
+	struct unit_codegen_state *unit = (struct unit_codegen_state *)state;
+	struct mie_builder *builder = gen->c_builder;
+	struct mie_func *current = mie_builder_get_current_func(builder);
+
+	enum ivy_status status = IVY_OK;
+	if (!current || current != unit->s_immediate) {
+		status = switch_to_immediate_func(gen, unit);
+	}
+
+	if (status != IVY_OK) {
+		return CODEGEN_RESULT_ERR(status);
+	}
+
+	codegen_push_generator(gen, CODE_GENERATOR_RETURN, 0, NULL);
+	return CODEGEN_RESULT_OK(CODEGEN_R_REPEAT_NODE);
+}
+
 #if 0
 static struct code_generator_result gen_var_declaration(
 	struct ivy_codegen *gen, struct code_generator_state *state,
@@ -272,6 +293,7 @@ struct code_generator unit_generator = {
 	.g_state_fini = state_fini,
 	.g_node_generators = {
 		NODE_CODEGEN(VAR, gen_var_declaration),
+		NODE_CODEGEN(RETURN, gen_return),
 		NODE_CODEGEN(UNIT_PACKAGE, gen_unit_package),
 		NODE_CODEGEN(UNIT_IMPORT, gen_unit_import),
 	},