I want to parse a LLVM IR file and perform certain operation accordingly, Wondering if there is an ANTLR Grammar available for LLVM IR, this will make my job much simpler?
The largest repository of grammars I know of is here. I don't see your grammar in the list, sorry. Terence Parr makes mention of it in this article, but that's all I can find, but it's quite old and seems to be based on ANTLR3.
I got this file from one of the github repositories:
https://github.com/rwl/JLLVM/blob/master/src/cn/edu/sjtu/jllvm/VMCore/Parser/LLVM.g
It is a part of JLLVM source code(JLLVM is a Java version of LLVM Core. To get more info about JLLVM you should follow the link: http://tcloud.sjtu.edu.cn/wiki/index.php/User:Liuhaots:JLLVM)
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I want to make a plugin for a language for the Intellij Idea IDE. The language has been developped using Eclipse Xtext and is open source. A plugin already exists for Eclipse.
My goal is to port this language to Intellij Idea. I want to be able to use Intellij to create source files, to have the specific syntax highlighting and to be able to compile and run programs written with this language.
Is there a simple way to generate the Intellij Idea plugin using the Xtext project?
If not is there an efficient solution to be able to have the specific syntax highlighting in Intellij? (an automatic way if possible, I would prefer not rewriting everything everytime the Xtext project is updated)
Short answer
Yes, with a bit of work.
Long Answer
Sadly, Xtext uses antlr in the background and IntelliJ use their own grammar kit based on Parsing Expression Grammars. As such, the parsing and editor code generated by XText, as you might have guessed, will not work.
In order to get your language working in IntelliJ you will need to:
Create grammar *.bnf file
Generate lexer *.flex file, possibly tweak it and then run JFlex generator
Implement helper classes to provide, among others, file recognition via file extension, syntax highlighting, color settings page, folding, etc.
The *.flex file is generated from the bnf. Luckily, most of the classes in step 3 follow a very similar structure so they can be easily generated (more on that later). So basically, if you manage to generate the *.bnf file, you are 80% there.
Although from different technologies, the syntax of bnf files is very similar to XText files. I recently migrated some antlr grammars to IntelliJ's bnf and I had to do very small changes. Thus, it should be possible to autogenerate the bnf files from your XText ones.
That brings me back to point 3. Using XTend, Epsilon's EGL, or similar, it would be easy to generate all the boiler plate classes. As part of the migration I mentioned before I also did this. I am in the process of making the code public, so I will post it here when done and add some details.
I am wondering if I can generate ANTLR grammar from java source code. I want to do some kind of research project, but I am just exploring different open sources to see which one is best.
For ANTLR, do I always have to write a grammar and pass it to the ANTLR?
Is there a way to generate grammar from an existing Java source code?
Not easily. ANTLR generate a recursive descent parser from your grammar, encoding the tests into procedural code, as well as lots of other bookkeeping stuff.
Knowing how the code is generated, you might be able to take it apart but you'll have to reach into the middle of generated statements and that isn't easy without a full parser for the generated language. (Hint: regex won't work).
I don't see a lot of point of this exercise. Why don't you just use the original grammar?
Is there a method to propagate a comment in ANTLR to the code generated?
e.g. if I have the Subversion revision number keyword ($Rev$) in a comment within the *.g4 file, is there a way for this to be within the generated code, so that I know that the parser was generated with that revisions version of the language?
Cheers,
Adam
At this time, we are not copying the comments from the grammar into the generated code, although we should. Added https://github.com/antlr/antlr4/issues/375
I need a parser (mainly for the "select" type of queries) and avoid the hassle of doing it from scratch. Does anybody know how to use the scan.l/gram.y of pgsql for this purpose? I've looked up pgpool too, but it seems similar. Currently, it might be very helpful if someone could give instructions to compile the parser (using the makefile provided maybe) without errors so that it can be supplied (valid?) queries and outputs the parse tree (in whatever form)!
You probably cannot take any file from postgres source tarball and compile it separately. Parser use internal OOP structures (implemented in C). But there is some possibility (not simple) - ecpg preprocessor try to transform PostgreSQL gram file to secondary gram file - and you can use same mechanism. It use a small utility parse.pl (it is part of PostgreSQL source code (src/postgresql/src/interfaces/ecpg/preproc))
PostgreSQL compiles the language parser using yacc. Presumably you could take the yacc files and create a compatible parser with very little effort. Note you must have flex and yacc installed to do this.
Note this is not taking a .c file from source and transplanting it into your system. All you are getting is the parser, not the planner or anything else.
Given the level of detail in the question no more detail can be possible. Perhaps you could start there and post another question when you get stuck.
As an project assignment, I need to parse a plain-C grammar from Java to generate AST output. As a startup, I am using the file c.jj that I have found among grammar files at
http://java.net/projects/javacc/sources/svn/
but I found that it only has syntactic and lexical actions and no real semantics for parsing C source. Is there some other source that incorporate typedef, variables, construct functions, include files?
You could go looking for a complete grammar. Will you learn much this way?
You could ask your lecturer which would impress them more: implementing some small subset of C grammar by writing your own rules, or by searching google for alternative complete rules?
I trust writing your own rules - and even your own hand-crafted parser - will be more a more useful exercise. Even if its only parsing expressions.