A High performance, VCD Parser written in Rust

Current Features

FastWave currently offers highly robust error(at least on the sample VCD files in this repository) handling which GTKWave doesn't have. For eample, selecting the UTILIZATON_ENABLED after opening test2x2_regex22_string1.vcd, (one of the sample xilinx vcd test files) in GtkWave, will crash GtkWave since this signal is malformed. FastWave on the otherhand simply informs you the signal is malformed.

Performance

Methods

Below is a table of performance comparisons on a large 3.04GB VCD file that can be found here.

For getting the GtkWave results, I fired up GtkWave, clicke on File->Open New Window, and selected the large VCD file. I started my stopwatch as soon as I pressed enter to beging loading the VCD file, and stopped my stopwatch once the GtkWave titlebar reached 100%.

To get the memory consumption, I opened Activity Monitor on Mac, and recorded the GtkWave memory usage before and after loading the large VCD file, and took the difference.

I noticed that when running FastWave in the VsCode terminal as opposed to the MacOS system terminal or the Lapce terminal, FastWave is notably slower.

Results

Software	Time(s)	Memory(MB)
FastWave	15.09	267.3
GtkWave	~30	89.8

Current Limitations

Unable to handle VCD files that have signals with more than 2^32 - 1 = 4,294,967,295 deltas/changes.

Running

This repository comes with several smaller VCD files emitted from various EDA tools. If you want a larger VCD file, grab one from here.

The first build of the program may take some time.

cargo run --release test-vcd-files/aldec/SPI_Write.vcd

You can run all the tests with cargo test

Testing on Bad Files

You may wish to test the parser on a malformed VCD just to make sure that the parser gives useful/sane errors.

Here's a command to test on a malformed VCD: cargo run --release test-vcd-files/VCD_file_with_errors.vcd

TODO

Features

be explicit with imports, remove exports as possible once FastWave is known to be fairly stable.
do a read through all the code
- make contents of src/types.rs public as necessary.
Print out git commit or release number.
Take a look at GTKWave parser to compare efficiency.
Move part of the performance section to another markdown file.

Repairs

make a custom date parser for possibly up to 18 different versions(that is, for each possible tool).
Consolidate error messages and add cursors throughout.
Fix warnings especially usage and restriction warnings once I'm able to successfully parse all sample VCDs.

Code Consistency

Change error messages to line and filenames. Go through all calls to unwrap.
- search for any unwraps or any direct vectors indexing
Handle TODOs
Remove debug code/comments.

Marketing

Send survey to community

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