Completely refactor code generation

1 files changed, 151 insertions, 0 deletions

diff --git a/src/output_source_slr.cpp b/src/output_source_slr.cpp
new file mode 100644
index 0000000..4c82922
--- /dev/null
+++ b/src/output_source_slr.cpp
@@ -0,0 +1,151 @@
+/*
+  Copyright (c) 2015, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#include "output_source_slr.hpp"
+
+
+namespace solar {
+
+void output_source_slr_t::emit_state_shift(unsigned state) {
+	std::map<unsigned, std::set<symbol_t>> shifts;
+
+	for (const symbol_t &token : get_generator()->get_terminals()) {
+		auto it = get_generator()->get_shifts().find(std::make_pair(state, token));
+		if (it == get_generator()->get_shifts().end())
+			continue;
+
+		std::set<symbol_t> &symbols = shifts.insert(std::make_pair(it->second, std::set<symbol_t>())).first->second;
+		symbols.insert(token);
+	}
+
+	for (const auto &entry : shifts) {
+		for (const symbol_t &sym : entry.second)
+			write_case(symbol_case(sym));
+
+		write_line_("parser->stack[++parser->top].state = ", entry.first);
+		write_line_("return 1");
+		write_line();
+	}
+}
+
+void output_source_slr_t::emit_state_reduce_code(const item_t &item, unsigned rule_id) {
+	const auto &rhs = item.get_rhs();
+	const std::string &type = get_generator()->get_grammar().get_nonterm_type(item.get_lhs());
+	const auto &vars = get_generator()->get_grammar().rules[rule_id].variables;
+
+	function_t reduce_func("", prefixed(combine("reduce_", rule_id)));
+
+	for (unsigned i = 0; i < vars.size(); i++) {
+		if (vars[i].first.empty())
+			continue;
+
+		reduce_func.add_arg("", combine("parser->stack[parser->top + ", i, "].value.", symbol_value(rhs[i])));
+	}
+
+	for (const auto &arg : get_generator()->get_grammar().extra_args)
+		reduce_func.add_arg(arg);
+
+	if (type.empty())
+		write_line_(call(reduce_func));
+	else
+		write_line_("result.symbol_", item.get_lhs(), " = ", call(reduce_func));
+
+	for (unsigned i = 0; i < vars.size(); i++) {
+		if (!vars[i].second)
+			continue;
+
+		auto it = get_generator()->get_grammar().destructors.find(rhs[i]);
+		if (it == get_generator()->get_grammar().destructors.end())
+			continue;
+
+		write_line_(it->second, "(parser->stack[parser->top + ", i, "].value.", symbol_value(rhs[i]), ")");
+	}
+
+	if (!type.empty())
+		write_line_("parser->stack[parser->top].value.symbol_", item.get_lhs(), " = result.symbol_", item.get_lhs());
+}
+
+bool output_source_slr_t::emit_state_reduce(unsigned state) {
+	std::map<unsigned, std::set<symbol_t>> reductions;
+
+	for (const symbol_t &token : get_generator()->get_terminals()) {
+		auto it = get_generator()->get_reductions().find(std::make_pair(state, token));
+		if (it == get_generator()->get_reductions().end())
+			continue;
+
+		std::set<symbol_t> &symbols = reductions.insert(std::make_pair(it->second, std::set<symbol_t>())).first->second;
+		symbols.insert(token);
+	}
+
+	for (const auto &entry : reductions) {
+		if (reductions.size() == 1) {
+			write_default();
+		}
+		else {
+			for (const symbol_t &sym : entry.second)
+				write_case(symbol_case(sym));
+		}
+
+		const rule_t &rule = get_generator()->get_grammar().rules[entry.first];
+
+		if (rule.item.get_rhs().size())
+			write_line_("parser->top -= ", rule.item.get_rhs().size());
+
+		if (!rule.action.empty())
+			emit_state_reduce_code(rule.item, entry.first);
+
+		emit_gotos(rule.item.get_lhs());
+
+		if (reductions.size() != 1) {
+			write_line_("break");
+			write_line();
+		}
+
+	}
+
+	return (reductions.size() == 1);
+}
+
+void output_source_slr_t::emit_state(unsigned state) {
+	block_t switch_token(this, "switch (token)");
+
+	if (get_generator()->get_shifts().find(std::make_pair(state, symbol_t::make_nonterm(""))) != get_generator()->get_shifts().end()) {
+		write_case(0);
+		write_line_("return 0");
+		write_line();
+	}
+
+	emit_state_shift(state);
+
+	bool def = emit_state_reduce(state);
+
+	if (!def) {
+		write_default();
+		write_line_("return -1");
+	}
+}
+
+}