output: also collapse goto case branches

1 files changed, 30 insertions, 0 deletions

diff --git a/src/output.cpp b/src/output.cpp
index cd08a9e..cfefbbb 100644
--- a/src/output.cpp
+++ b/src/output.cpp
@@ -213,6 +213,36 @@ void output_t::emit_reductions() {
 	}
 }
 
+void output_t::emit_gotos(const std::string &lhs) {
+	std::map<unsigned, std::set<unsigned>> gotos;
+
+	for (size_t state = 0; state < get_generator()->get_state_count(); state++) {
+		auto it = get_generator()->get_gotos().find(std::make_pair(state, lhs));
+		if (it == get_generator()->get_gotos().end())
+			continue;
+
+		std::set<unsigned> &states = gotos.insert(std::make_pair(it->second, std::set<unsigned>())).first->second;
+		states.insert(state);
+	}
+
+	if (gotos.size() == 1) {
+		auto it = gotos.begin();
+		std::fprintf(source_file, "\t\t\t\tparser->stack[++parser->top].state = %u;\n", it->first);
+	}
+	else {
+		std::fprintf(source_file, "\t\t\t\tswitch (parser->stack[parser->top].state) {\n");
+
+		for (const auto &entry : gotos) {
+			for (unsigned state : entry.second)
+				std::fprintf(source_file, "\t\t\t\tcase %u:\n", state);
+			std::fprintf(source_file, "\t\t\t\t\tparser->stack[++parser->top].state = %u;\n", entry.first);
+			std::fprintf(source_file, "\t\t\t\t\tbreak;\n\n");
+		}
+
+		std::fprintf(source_file, "\t\t\t\t}\n");
+	}
+}
+
 void output_t::emit_states() {
 	for (size_t state = 0; state < get_generator()->get_state_count(); state++)
 		emit_state(state);