[mlir-tensorrt] NFC: add contribution guidelines

Signed-off-by: Christopher Bate <[email protected]>

mlir-tensorrt/CONTRIBUTING.md

@@ -0,0 +1,133 @@
+# Contributing to MLIR-TensorRT
+
+Contributions are welcome!
+
+## Coding Standard
+
+We will strive to follow the same coding standard as upstream MLIR, which is
+described here: https://llvm.org/docs/CodingStandards.html
+
+Python files are formatted using the [`black` formatter](https://black.readthedocs.io/en/stable/).
+
+## How to Submit a PR
+
+- Fork the repo on GitHub
+- Use GitHub CLI to submit PRs.
+
+Make sure you push your branches to your fork instead of the main repo.
+
+```bash
+git remote add fork [url to your fork]
+```
+
+1. Checkout a branch ```git switch -c my-feature```
+2. Do work
+3. `git clang-format HEAD~1`
+4. `git stage` your files and `git commit -s` with a message following guidelines
+   below. Commits must contain a "sign off" message to indicate that the code you are
+   contributing is your own work and contributed under our existing license.
+5. `git push fork`
+6. `gh pr create`
+
+
+### Testing
+
+Until we have some sort of automated externally-facing continuous testing setup, we will test PRs
+using our internal infrastructure. In the meantime, developers should post their own test
+results to the PR as a comment for the most basic sanity check. Just post the output of
+
+```
+ninja -C build check-mlir-tensorrt check-mlir-executor check-mlir-tensorrt-dialect
+```
+
+### Merging PRs
+
+After review, when it is time to merge the change, simply do:
+
+1. `gh pr merge --squash --delete-branch`
+
+## Guidelines for PRs
+
+Each PR is one commit. Multiple commits will be automatically squashed. We are
+operating in git fast-forward-only mode, so you will need to rebase periodically
+if you are on a long-lived branch.
+
+Each commit should generally  follow a multi-line style as follows:
+
+```
+[SomeTag] A short headline
+
+Explanation of what the commit entails. It can be as long as you like, the more
+detail the better. No functional change should be made without an explanation.
+```
+
+The exception to this policy is for "Non-Functional-Changes" (NFC)
+commits which are things like correcting typos and updating documentation
+in that case it's fine to have something like:
+
+```NFC: fix typo in documentation```
+
+Functional changes and bug fixes should have an accompanying test.
+Usually this will be in the form of a LIT test.
+
+Each commit should be focused and atomic. Break your work up into small commits
+as much as possible.
+
+#### Signing Your Work
+
+* We require that all contributors "sign-off" on their commits. This certifies
+  that the contribution is your original work, or you have rights to submit it
+  under the same license, or a compatible license.
+
+  * Any contribution which contains commits that are not Signed-Off will not be
+    accepted.
+
+* To sign off on a commit you simply use the `--signoff` (or `-s`) option when
+  committing your changes:
+
+  ```bash
+  $ git commit -s -m "Add cool feature."
+  ```
+  This will append the following to your commit message:
+  ```
+  Signed-off-by: Your Name <[email protected]>
+  ```
+
+* Full text of the DCO:
+
+```
+Developer Certificate of Origin
+Version 1.1
+
+Copyright (C) 2004, 2006 The Linux Foundation and its contributors.
+
+Everyone is permitted to copy and distribute verbatim copies of this
+license document, but changing it is not allowed.
+
+
+Developer's Certificate of Origin 1.1
+
+By making a contribution to this project, I certify that:
+
+(a) The contribution was created in whole or in part by me and I
+    have the right to submit it under the open source license
+    indicated in the file; or
+
+(b) The contribution is based upon previous work that, to the best
+    of my knowledge, is covered under an appropriate open source
+    license and I have the right under that license to submit that
+    work with modifications, whether created in whole or in part
+    by me, under the same open source license (unless I am
+    permitted to submit under a different license), as indicated
+    in the file; or
+
+(c) The contribution was provided directly to me by some other
+    person who certified (a), (b) or (c) and I have not modified
+    it.
+
+(d) I understand and agree that this project and the contribution
+    are public and that a record of the contribution (including all
+    personal information I submit with it, including my sign-off) is
+    maintained indefinitely and may be redistributed consistent with
+    this project or the open source license(s) involved.
+  ```