ANTLR4-Verilog-Python
Generated files from ANTLR4 for Verilog parsing in Python
Tutorial
Install this Python package
python3 -m pip install antlr4_verilog
Use your own listener to walk through the AST:
from antlr4_verilog import InputStream, CommonTokenStream, ParseTreeWalker
from antlr4_verilog.verilog import VerilogLexer, VerilogParser, VerilogParserListener
design = '''
module ha(a, b, sum, c);
input a, b;
output sum, c;
assign sum = a ^ b;
assign c = a & b;
endmodule
'''
class ModuleIdentifierListener(VerilogParserListener):
def exitModule_declaration(self, ctx):
self.identifier = ctx.module_identifier().getText()
lexer = VerilogLexer(InputStream(design))
stream = CommonTokenStream(lexer)
parser = VerilogParser(stream)
tree = parser.source_text()
listener = ModuleIdentifierListener()
walker = ParseTreeWalker()
walker.walk(listener, tree)
print(listener.identifier) # 'ha'Take a look at other listener methods for Verilog and SystemVerilog
How to generate those files
System requirements (Ubuntu):
sudo apt-get install -y default-jre
sudo apt-get install -y default-jdk
sudo apt-get install -y curl
- Get ANTLR4:
curl https://www.antlr.org/download/antlr-4.9-complete.jar -o extra/antlr-4.9-complete.jar- Get ANTLR grammars:
git clone https://github.com/antlr/grammars-v4.git extra/grammars-v4
- Call ANTLR for Verilog grammar:
java -Xmx500M -cp "extra/antlr-4.9-complete.jar:${CLASSPATH}" org.antlr.v4.Tool -Dlanguage=Python3 -visitor `pwd`/extra/grammars-v4/verilog/verilog/VerilogLexer.g4 `pwd`/extra/grammars-v4/verilog/verilog/VerilogParser.g4 `pwd`/extra/grammars-v4/verilog/verilog/VerilogPreParser.g4 -o src/antlr4-verilog/verilog
- Call ANTLR for SystemVerilog grammar:
java -Xmx500M -cp "extra/antlr-4.9-complete.jar:${CLASSPATH}" org.antlr.v4.Tool -Dlanguage=Python3 -visitor `pwd`/extra/grammars-v4/verilog/systemverilog/SystemVerilogLexer.g4 `pwd`/extra/grammars-v4/verilog/systemverilog/SystemVerilogParser.g4 `pwd`/extra/grammars-v4/verilog/systemverilog/SystemVerilogPreParser.g4 -o src/antlr4-verilog/systemverilog
How to test the grammar
- Generate Java files:
java -Xmx500M -cp "extra/antlr-4.9-complete.jar:${CLASSPATH}" org.antlr.v4.Tool -Dlanguage=Java -visitor `pwd`/extra/grammars-v4/verilog/verilog/VerilogLexer.g4 `pwd`/extra/grammars-v4/verilog/verilog/VerilogParser.g4 `pwd`/extra/grammars-v4/verilog/verilog/VerilogPreprocessorParser.g4 -o test/testrig/verilog
java -Xmx500M -cp "extra/antlr-4.9-complete.jar:${CLASSPATH}" org.antlr.v4.Tool -Dlanguage=Java -visitor `pwd`/extra/grammars-v4/verilog/systemverilog/SystemVerilogLexer.g4 `pwd`/extra/grammars-v4/verilog/systemverilog/SystemVerilogParser.g4 `pwd`/extra/grammars-v4/verilog/systemverilog/SystemVerilogPreParser.g4 -o test/testrig/systemverilog
- Compile these recently generated files:
javac -cp "extra/antlr-4.9-complete.jar:${CLASSPATH}" test/testrig/verilog/*.java
javac -cp "extra/antlr-4.9-complete.jar:${CLASSPATH}" test/testrig/systemverilog/*.java
- Create JAR files:
jar cf test/testrig/verilog.jar -C test/testrig/verilog .
jar cf test/testrig/systemverilog.jar -C test/testrig/systemverilog .
- Finally, for
test.vandtest.svfiles:
java -Xmx500M -cp "extra/antlr-4.9-complete.jar:test/testrig/verilog.jar:${CLASSPATH}" org.antlr.v4.gui.TestRig Verilog source_text test/testrig/test.v -tree
java -Xmx500M -cp "extra/antlr-4.9-complete.jar:test/testrig/systemverilog.jar:${CLASSPATH}" org.antlr.v4.gui.TestRig SystemVerilog source_text test/testrig/test.sv -tree
You can use
-guito test it interactively
Acknowledgement
We would like to appreciate the work from the ANTLR team and the Verilog/SystemVerilog grammar written by Mustafa Said Ağca.
