finding all dependencies in a verilog compile - verilog

I'm trying to cheaply and accurately predict all the SystemVerilog dependencies for a build flow. It is ok to over-predict the dependencies and find a few Verilog files that aren't sv dependencies, but I don't want to miss any dependencies.
Do I actually have to parse the Verilog in order to determine all its dependencies? There are tick-include preprocessor macros, but those tick-include don't seem to load all the code currently getting compiled. There is a SYSTEM\_VERILOG\_PATH environment variable. Do I need to parse every SystemVerilog file in that SYSTEM\_VERILOG\_PATH variable in order to determine which modules are defined in which files?

One good way (if this is synthesizable code) is to use your synthesis tool file list (e.g. .qsf for Altera). That tends to be complete, but if it isn't, you can look at the build log for missing files that it found.

From a readily compiled environment it is possible to dump the source files
(e.g. Cadence
-- To list source files used by the snapshot 'worklib.top:snap'
% ncls -source -snapshot worklib.top:snap
)
but if you are starting from scratch I am afraid there is no easy solution. I would go for the pragmatic one: have a config file with all the directories that contain .sv files and then compile everything in it. If your project has a proper file structure, you could also modularize this by supplying config files for every major block.
Hope that helps.

I know Questa has a command line option where it will generate a makefile for you with all the dependencies in it after you have compiled your design. I'm not sure if the other simulators have that.
Another option is to browse and dump your compiled library in your simulator. You probably won't get the actual filenames the modules are compiled from, but it'll be a lot easier to parse all your verilog files for the module names that show up in the compiled library.

Related

Makefile explanation. Understanding someone else's Makefile

I am relatively new to programming on Linux.
I understand that Makefiles are used to ease the compiling process when compiling several files.
Rather than writing "g++ main.cpp x.cpp y.cpp -o executable" everytime you need to compile and run your program, you can throw it into a Makefile and run make in that directory.
I am trying to get a RPi and Arduino to communicate with each other using the nRF24L01 radios using tmrh20's library here. I have been successful using tmrh20's Makefile to build the the executable needed (on the RPi). I would like to, however, use tmrh20's library to build my own executables.
I have watched several tutorial videos on Makefiles but still cannot seem to piece together what is happening in tmrh20's.
The Makefile (1) in question is here. I believe it is somehow referencing a second Makefile (2) (for filenames?) here. (Why is this necessary?)
If it helps anyone understand (it took me a while) I had to build using SPIDEV (the instructions here) the Makefile (3) in the RF24 directory which produced several object files which I think are relevant to Makefile (1)&(2).
How do I find out what files I need to make my own Makefile, from tmrh20's Makefile (if that makes sense?) He seems to use variables in his Makefile that are not defined? Or are perhaps defined elsewhere?
Apologies for my poor explanation.
The canonical sequence is not just make and make install. There is an initial ./configure step (such a file is here) that sets up everything and generates several files used in the make steps.
You only need to run this configure script successfully only once, unless you want to change build parameters. I say "successfully" because the first execution will usually complain that you are missing libraries or header files. But ince ./configure runs without errors, make and make install should run without errors.
PS: I didn't try to compile it, but since the project has a rather comprehensive configure it is likely complete and you shouldn't need to tweak makefiles if your follow the usual procedure.
The reason for splitting the Makefiles in the way you've mentioned and linked to here is to separate the definition of the variables from the implementation. This way you could have multiple base Makefiles that define their PROGRAM variable differently, but all do the same thing based on the value of that variable.
In my own personal opinion, I see some value here - but there very many ways to skin this proverbial cat.
Having learned GNU Make the hard way, I can only recommend you do the same. There's a slight steep curve at the beginning, but once you get the main concepts down following other peoples Makefiles gets pretty easy.
Good luck: https://www.gnu.org/software/make/manual/html_node/index.html

How to use the binary output of a Cargo project as the input of another one?

In order to reduce the executable size of a Rust program (called runtime in my code), I am trying to compress it and then include it in a second program (called szl) that decompresses it and executes it.
I have done that by using a Cargo build script in szl that opens the output binary from runtime, compresses it, and then generates a file that is ready for use by include_bytes!.
The issue with this approach is the dependencies are not handled properly. For example, Cargo may try to build szl before runtime (and fail), and when the source code of runtime is modified, szl is not rebuilt.
Is there a way to tell Cargo that szl depends on the binary from runtime (and transitively on the source code of runtime), or should I use another approach such as an external Makefile?
While not exactly your use case, you might get it to work with the links manifest key. It would allow you to express a dependency between the two programs and you can pass more information with DEP_FOO_KEY variables.
Before you go to such drastic measures, it might be worth it to try other known strategies for reducing rust binary size (such as calling strip, remove debug symbols, LTO, panic=abort) etc.

Using UglifyJs on the whole Node project?

I need to obfuscate my source code as best as possible so I decided to use uglifyjs2.. Now I have the project structure that has nested directories, how can I run it through uglifyjs2 to do the whole project instead of giving it all the input files?
I wouldn't mind if it minified the whole project into a single file or something
I've done something very similar to this in a project I worked on. You have two options:
Leave the files in their directory structure.
This is by far the easier option, but provides a much lower level of obfuscation since someone interested enough in your code basically has a copy of the logical organization of files.
An attacker can simply pretty-print all the files and rename the obfuscated variable names in each file until they have an understanding of what is going on.
To do this, use fs.readdir and fs.stat to recursively go through folders, read in every .js file and output the mangled code.
Compile everything into a single JS file.
This is much more difficult for you to implement, but does make life harder on an attacker since they no longer have the benefit of your project's organization.
Your main problem is reconciling your require calls with files that no longer exist (since everything is now in the same file).
I did this by using Uglify to perform static analysis of my source code by analyzing the AST for calls to require. I then loaded the source code of the required file and repeated.
Once all code was loaded, I replaced the require calls with calls to a custom function, wrapped each file's source code in a function that emulates how node's module system works, and then mangled everything and compiled it into a single file.
My custom require function does most of what node's require does except that rather than searching the disk for a module, it searches the wrapper functions.
Unfortunately, I can't really share any code for #2 since it was part of a proprietary project, but the gist is:
Parse the source text into an AST using UglifyJS.parse.
Use the TreeWalker to visit every node of the AST and check if
node instanceof UglifyJS.AST_Call && node.start.value == 'require'
As I have just completed a huge pure Nodejs project in 80+ files I had the same problem as OP. I needed at least a minimal protection for my hard work, but it seems this very basic need had not been covered by the NPMjs OS community. Add salt to injury the JXCore package encryption system was cracked last week in a few hours so back to obfuscation...
So I created the complete solution, that handles file merging, uglifying. You have the option of leaving out specified files/folders as well from merging. These files are then copied to the new output location of the merged file and references to them are rewritten auto.
NPMjs link of node-uglifier
Github repo of of node-uglifier
PS: I would be glad if people would contribute to make it even better. This is a war between thieves and hard working coders like yourself. Lets join our forces, increase the pain of reverse engineering!
This isn't supported natively by uglifyjs2.
Consider using webpack to package up your entire app into a single minified .js file, excluding node_modules:
http://jlongster.com/Backend-Apps-with-Webpack--Part-I
I had the same need - for which I created node-optimize and grunt-node-optimize.
https://www.npmjs.com/package/grunt-node-optimize

Build-time determination of SCons targets

I have some targets that need to be built in order to determine what some of my other targets are. How do I tell SCons?
An example:
A script, generate is run on some configuration files. This script generates include path and build flags based on information in the configuration files. In order to build a SCons Object, I need to read the generated files.
I was just running Execute() on generate but it's now got lots of files to generate and it takes a good amount of time, so I only want to run it when it or a configuration file changes. How do I tell SCons to ask me at build time for some more targets once this Command has done anything it needs to do?
ok, some SCons clarifications first. Scons have two phases in doing a build. First, in the analysis phase all Scons scripts are executed and the result is a static dependency tree describing source and target files for all the builders defined in the scripts. Next, based on that tree, the build database from last build and the signatures of the files on disc, all builders with out of date targets are rebuild.
Now to your question. If you want to only run generate when necessary (when generate or configuration files changes), then running generate as a part of the analysis phase is out of the question. So don't use Execute(). Instead generate must be a builder of its own. So far so good.
Now you have two builders, the first builder generate and the second builder, I call it buildObject. buildObject depend in the targets of generate, but as you state, the generate targets are unknown at analysis time (because generate is not run, it is only set up as a builder). Having unknown targets at analysis time is a classic challenge with SCons, and there are no easy way to solve it.
I normally solve it by using what I call a SCons.pleaser file.
In your case it would be a known target that generate generates containing a high res timestamp. The buildObject builder then take this file as a source.
Now, if your configuration files has not changed, generate will not run, the SCons.pleaser will not change, and the buildObject will not run. If you change you configuration files, generate will run, the SCons.pleaser will change, and the buildObject will run as well.
Regards
The solution I went with was to make a new SConstruct that knows how to do the generate phase, and Execute() it early in my SConscripts before I get to the bits where its output is needed. It works well, since it just builds things as necessary with the small fixed overhead of invoking SCons from within SCons.

How to get a list of paths in /etc/ld.so.conf on Linux

What is the most portable and robust way to get the list of paths, configured by /etc/ld.so.conf and files included from it? Parsing the file manually seems to be not a good idea — the format is likely to change in the future revisions.
To allow better understanding of the question, I will give you specific details below. Note that, despite these details, this is a general programming question, applicable to other situations.
There is a program, called LuaRocks. It is a package manager for Lua programming language (somewhat like Ruby gems or Python eggs). LuaRocks packages are called "rocks".
As a convenience feature, LuaRocks allows a rock author to specify a list of external dependencies for a rock, formulated as a list of C header files and / or dynamic library files. (.so on Linux.) If the specified file does not exist, the rock can't be installed.
Currently, on Linux, LuaRocks by default checks .so file existance by searching for the file in two hardcoded paths, /usr/lib and /usr/local/lib.
I believe that this is incorrect behaviour, and it is broken by the recent changes in the Ubuntu and other Debian distributions.
Update: the paths are not hardcoded per se, but are user-configurable in the config file. Still, IMO, not a best solution.
Instead (as I understand it), LuaRocks should look up file in the paths, specified by /etc/ld.so.conf and files included from it.
(Now please re-read the question above ;-) )
You shouldn't need to parse /etc/ld.so.conf or any of the config files - if you run 'ldconfig', it will scan the configured directories and generate a cache file.
Then, subsequently when you attempt a dlopen it'll automatically find the files by iterating through the cached library directories. Same thing with compiling and giving -lSomeLib, you shouldn't need to specify -L/my/other/path if you've got it configured in ld.so.conf(.d)
autoconf accomplishes this by attempting to compile a test program that links to the shared library, but that's just a functional wrapper around the dlopen() call.
So, while other methods may not necessarily be 'wrong', at the root of it attempting to link to the library or doing a dlopen() are the 'most right' ways of doing it.
Consider this, if you attempt to link to a library in a directory that ISN'T cached in /etc/ld.so.cache, when you try to run the program it will fail because it won't be able to dlopen() the library!
Hence, any 'good' shared library will be in /etc/ld.so.cache and be linkable/dlopen()able, this means that gcc can use it to link and that the user-generated library or executable will be able to open it when it executes.
You can circumvent this by expressly setting the environment variable LD_LIBRARY_PATH, or LD_PRELOAD_PATH - but each of these has it's own caveats and should be avoided if possible for 'standard' use.
A good write-up on writing shared libraries covers some of these issues, and is a good read for anyone working on programmatic consuming of other-shared libraries. Ulrich Drepper's How to write shared libraries.
According to the FHS, the following are valid locations for dynamic libraries:
/lib*/
/opt/*/lib*/
/usr/lib*/
/usr/local/lib*/
(And most likely ~/lib*/ as well.)
All entries in my /etc/ld.so.conf.d/* conform to this. Some entries reference subdirectories below the FHS dirs, which probably means that you can use the libraries in there without path information.
Now I don't know enough about LuaRocks. If you're limited to Lua-path-style globs (only ?), you cannot match these and have to parse the configs. Otherwise, you could just try to find them anywhere in these directories.
This would break on non-FHS-conforming systems (only option: parse config) and if a directory is not included in the config, the installer might see libraries that the linker cannot find.
These two seem acceptable to me, therefore I'd simply ignore the config and look at these dirs.
(Another possibility could be trying to link the library, this should automagically use the right path. However, this is platform-specific and maybe dangerous.)

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