lang: add match-expression parser/generator

lang/ast/match.c

@@ -132,12 +132,15 @@ static struct token_parse_result parse_arrow(
 	state->s_prev_token = IVY_SYM_EQUAL_RIGHT_ANGLE;
 
 	/* the next component is the branch body */
+#if 0
 	struct expr_parser_state *expr
 		= (struct expr_parser_state *)parser_push_state(
 			ctx, IVY_AST_EXPR, 0);
 
 	expr_add_terminator(expr, IVY_KW_END);
+	expr_add_terminator(expr, IVY_SYM_COMMA);
 	expr->s_subexpr_depth = 1;
+#endif
 	return PARSE_RESULT(IVY_OK, 0);
 }
 
@@ -199,6 +202,46 @@ static struct token_parse_result parse_end(
 	return PARSE_RESULT(IVY_OK, 0);
 }
 
+static struct token_parse_result parse_block(
+	struct ivy_parser *ctx, struct ivy_token *tok)
+{
+	struct match_parser_state *state
+		= parser_get_state(ctx, struct match_parser_state);
+
+	if (state->s_prev_token != IVY_SYM_EQUAL_RIGHT_ANGLE) {
+		return PARSE_RESULT(IVY_ERR_BAD_SYNTAX, 0);
+	}
+
+	struct block_parser_state *block
+		= (struct block_parser_state *)parser_push_state(
+			ctx, IVY_AST_BLOCK, 0);
+
+	return PARSE_RESULT(IVY_OK, 0);
+}
+
+static struct token_parse_result parse_expr(
+	struct ivy_parser *ctx, struct ivy_token *tok)
+{
+	struct match_parser_state *state
+		= parser_get_state(ctx, struct match_parser_state);
+
+	if (state->s_prev_token != IVY_SYM_EQUAL_RIGHT_ANGLE) {
+		return PARSE_RESULT(IVY_ERR_BAD_SYNTAX, 0);
+	}
+
+	struct expr_parser_state *expr
+		= (struct expr_parser_state *)parser_push_state(
+			ctx, IVY_AST_EXPR, 0);
+
+	if (tok->t_type != IVY_TOK_KEYWORD) {
+		expr_add_terminator(expr, IVY_KW_END);
+	}
+
+	expr_add_terminator(expr, IVY_SYM_COMMA);
+	expr->s_subexpr_depth = 1;
+	return PARSE_RESULT(IVY_OK, PARSE_REPEAT_TOKEN);
+}
+
 static enum ivy_status add_child(
 	struct parser_state *parent, struct ivy_ast_node *child)
 {
@@ -233,10 +276,12 @@ struct ast_node_type match_node_ops = {
 	.n_collect_children = match_collect_children,
 	.n_state_size = sizeof(struct match_parser_state),
 	.n_node_size = sizeof(struct ivy_ast_match_node),
+	.n_expr_parser = parse_expr,
 	.n_keyword_parsers = {
 		KW_PARSER(MATCH, parse_match),
 		KW_PARSER(IN, parse_in),
 		KW_PARSER(END, parse_end),
+		KW_PARSER(DO, parse_block),
 	},
 	.n_symbol_parsers = {
 		SYM_PARSER(EQUAL_RIGHT_ANGLE, parse_arrow),

lang/codegen/codegen.h

@@ -50,6 +50,7 @@ enum code_generator_type {
 	CODE_GENERATOR_FOR_LOOP,
 	CODE_GENERATOR_WHILE_LOOP,
 	CODE_GENERATOR_CASCADE,
+	CODE_GENERATOR_MATCH,
 };
 
 enum code_generator_scope_type {

lang/codegen/expr.c

@@ -277,6 +277,14 @@ static struct code_generator_result gen_for_loop(
 	return CODEGEN_RESULT_OK(CODEGEN_R_REPEAT_NODE);
 }
 
+static struct code_generator_result gen_match(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct ivy_ast_node *node, size_t depth)
+{
+	codegen_push_generator(gen, CODE_GENERATOR_MATCH, 0, NULL);
+	return CODEGEN_RESULT_OK(CODEGEN_R_REPEAT_NODE);
+}
+
 #if 0
 static struct code_generator_result gen_var_ref(
 		struct ivy_codegen *gen, struct code_generator_state *state,
@@ -725,5 +733,6 @@ struct code_generator expr_generator = {
 		NODE_CODEGEN(IDENT, gen_var_reference),
 		NODE_CODEGEN(COND_GROUP, gen_cond_group),
 		NODE_CODEGEN(FOR_LOOP, gen_for_loop),
+		NODE_CODEGEN(MATCH, gen_match),
 	},
 };

lang/codegen/match.c

@@ -0,0 +1,86 @@
+#include "codegen.h"
+
+#include <mie/ir/block.h>
+#include <mie/ir/func.h>
+#include <mie/ir/module.h>
+
+struct match_codegen_state {
+	struct code_generator_state s_base;
+};
+
+static struct code_generator_result gen_expr(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct ivy_ast_node *node, size_t depth)
+{
+	struct match_codegen_state *match = (struct match_codegen_state *)state;
+
+	codegen_push_generator(gen, CODE_GENERATOR_EXPR, 0, NULL);
+	return CODEGEN_RESULT_OK(CODEGEN_R_REPEAT_NODE);
+}
+
+static struct code_generator_result gen_match(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct ivy_ast_node *node, size_t depth)
+{
+	return CODEGEN_RESULT_OK(0);
+}
+
+static struct code_generator_result gen_block(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct ivy_ast_node *node, size_t depth)
+{
+	struct match_codegen_state *match = (struct match_codegen_state *)state;
+	struct mie_func *func = mie_builder_get_current_func(gen->c_builder);
+
+	codegen_push_generator(gen, CODE_GENERATOR_BLOCK, 0, NULL);
+	return CODEGEN_RESULT_OK(0);
+}
+
+static struct code_generator_result gen_discard(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct ivy_ast_node *node, size_t depth)
+{
+	struct match_codegen_state *match = (struct match_codegen_state *)state;
+	return CODEGEN_RESULT_OK(0);
+}
+
+static enum ivy_status state_init(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	uintptr_t argv, void *argp)
+{
+	struct match_codegen_state *match = (struct match_codegen_state *)state;
+
+	return IVY_OK;
+}
+
+static enum ivy_status state_fini(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct code_generator_value *result)
+{
+	struct match_codegen_state *match = (struct match_codegen_state *)state;
+	return IVY_OK;
+}
+
+static struct code_generator_result value_received(
+	struct ivy_codegen *gen, struct code_generator_state *state,
+	struct code_generator_value *value)
+{
+	struct match_codegen_state *match = (struct match_codegen_state *)state;
+	struct mie_func *func = mie_builder_get_current_func(gen->c_builder);
+
+	return CODEGEN_RESULT_OK(0);
+}
+
+struct code_generator match_generator = {
+	.g_type = CODE_GENERATOR_FOR_LOOP,
+	.g_state_size = sizeof(struct match_codegen_state),
+	.g_state_init = state_init,
+	.g_state_fini = state_fini,
+	.g_value_received = value_received,
+	.g_expr_generator = gen_expr,
+	.g_node_generators = {
+		NODE_CODEGEN(MATCH, gen_match),
+		NODE_CODEGEN(BLOCK, gen_block),
+		NODE_CODEGEN(DISCARD, gen_discard),
+	},
+};