Add ANTLR4 grammar and C++ parser

Signed-off-by: Dusty DeWeese <dustin.deweese@gmail.com>

Makefile

@@ -6,10 +6,50 @@
 #
 # SPDX-License-Identifier: ISC
 
+CXXFLAGS += -Wno-attributes -O3
+LDFLAGS += -lantlr4-runtime
+
+.PHONY: all
+all: parse_fasm fasm/parse_fasm.so
+
 PYTHON_FORMAT ?= yapf
 format:
 	$(IN_ENV) find . -name \*.py $(FORMAT_EXCLUDE) -print0 | xargs -0 -P $$(nproc) yapf -p -i
 
 check-license:
 	@./.github/check_license.sh
 	@./.github/check_python_scripts.sh
+
+
+parse_fasm: cpp/ParseFasm.o cpp/FasmParser.o cpp/FasmLexer.o
+	$(CXX) $(CXXFLAGS) $(LDFLAGS) $^ -o $@
+
+fasm/parse_fasm.so: cpp/ParseFasm.o cpp/FasmParser.o cpp/FasmLexer.o
+	$(CXX) $(CXXFLAGS) $(LDFLAGS) $^ -fPIC -shared -o $@
+
+cpp/ParseFasm.o: cpp/FasmLexer.h cpp/FasmParser.h
+
+cpp/FasmParser.cpp \
+cpp/FasmParser.h \
+cpp/FasmParser.interp \
+cpp/FasmParser.tokens \
+cpp/FasmParserBaseListener.cpp \
+cpp/FasmParserBaseListener.h \
+cpp/FasmParserBaseVisitor.cpp \
+cpp/FasmParserBaseVisitor.h \
+cpp/FasmParserListener.cpp \
+cpp/FasmParserListener.h \
+cpp/FasmParserVisitor.cpp \
+cpp/FasmParserVisitor.h : fasm/FasmParser.g4 cpp/FasmLexer.tokens
+	antlr -Dlanguage=Cpp -visitor -Xexact-output-dir -o cpp $<
+
+cpp/FasmLexer.cpp \
+cpp/FasmLexer.h \
+cpp/FasmLexer.interp \
+cpp/FasmLexer.tokens : fasm/FasmLexer.g4
+	antlr -Dlanguage=Cpp -Xexact-output-dir -o cpp $<
+
+.PHONY: clean
+clean:
+	rm -f cpp/FasmLexer* cpp/FasmParser* cpp/*.o parse_fasm fasm/parse_fasm.so
+