This replaces GetAstMatcher with AddMatcher because cxxForRangeStmt is a StatementMatcher. addMatcher has multiple definitions (https://clang.llvm.org/doxygen/classclang_1_1ast__matchers_1_1MatchFinder.html) and so this approach allows using the right addMatcher without writing per-call overloads.
To handle the `var`, I'm considering something like moving VarDecl logic into a VarMatcherBase so that I can just use CXXForRangeStmt's getLoopVariable. The problem is a for-range statement has multiple VarDecls, and getLoopVariable may be the easiest way to identify the real one.
Range-based for loops remain messed up -- I'm just disabling the test here and turning a blind eye.
Co-authored-by: Chandler Carruth <chandlerc@gmail.com>
TODOs in the test for known issues.
I may switch the approach to getting the variable type (on examination, this isn't working quite as well as I'd thought) but for now I think it's okay. I had an earlier approach though that may work better overall -- I'd been thinking this would work better, but as you can see in the null check for type information, I think I missed a key point.
Anyways, what'd really been vexing me was `int i, j` which I think I handle passably well now. There's obviously room for improvement, but given I've been going at this for a couple days now, I thought it best to checkpoint where I was.
This also includes some related framework changes to fix bumps I was running into. Overall the tool should operate a bit more smoothly with these changes. There are still issues with overlapping replacements, but I think it's primarily with range-based for loops which I just need to take some time to fix.
This might need some customization, e.g. `woff2_decompress.impl.carbon` (as a file with a `main`) might be better as `woff2_decompress.carbon`, but I thought at least putting on `.carbon` extensions would help perspectives on files.
This restructures the script to make it easier to access standard info (e.g. cpp_files) without passing everywhere.
This picks up a newer version of LLVM and the LLVM Bazel integration.
The big change here is that we can configure the LLVM targets that are
built, which allows us to dramatically reduce the build costs by
focusing on a couple of CPUs for the time being.
There are a few API updates needed as well.
This also rotates the cache version so we start with a clean Bazel cache
from here. Otherwise we'd potentially pay the cost of carrying around
stale bits of LLVM endlessly.
What this does:
- Sets up a `migrate_cpp` tool which currently only runs `clang-tidy`.
- This is intended to have more transformations in the future.
- Sets up a `migrate_cpp.sh` script.
- This copies the original woff2 code into a `carbon` directory and runs the `migrate_cpp` tool on it there.
- Adds the initial `carbon` directory of woff2
- To be clear, this is currently only updated via `clang-tidy`.
- More transformations should be expected in the future.
- Minor related edits. For example:
- Adjust pre-commit to skip the `carbon` directory, because it's third-party code and shouldn't be edited in the same way.
- Adds `@brotli_carbon` as a local repository so that we can "build" outputs.
- Makes clang-tidy from the bootstrap toolchain accessible for BUILD dependencies, as it's then used for `migrate_cpp`.
What this does not do:
- Any actual transformation of C++ code to Carbon
Co-authored-by: Matthew Riley <mdriley@gmail.com>
This is to support converting the code to Carbon. My theory with the setup is:
- Have the code available to build in C++ under `third_party/<project>/original`.
- Created a `third_party/<project>/carbon` for the converted version.
Having the existing code building should, I think, make it easier to run analysis on said code. Using a submodule means we should be aiming to keep it pristine, for easy comparison / updates.
The Bazel bits are collected into a directory and given less confusing
names (I hope). Other than names, everything is a direct copy from the
toolchain repository without any edits.
A few files needed to be merged in:
- `.gitignore`
- `.pre-commit-config.yaml`
Subsequent commits will add relevant C++ infrastructure and then the
source code itself.
Jon Meow
