Merge pull request #9 from shigoel/release_prep

Update LICENSE, external contributing guidelines, and the README

.github/pull_request_template.md

@@ -0,0 +1,31 @@
+# Before your submission:
+
+* Ensure your PR follows the [contribution
+  guidelines](https://github.com/leanprover/LNSym/blob/main/CONTRIBUTING.md).
+
+* Remember to document and comment your code.
+
+* Remove this section, up to and including the `---` before submitting.
+
+---
+
+### Issues:
+
+Resolves #<issue_number>.
+
+Remove this section if this PR doesn't address any open issues.
+
+### Description:
+
+A detailed description of your contribution. Why is this change
+necessary?
+
+### Testing:
+
+What tests have been run? Did `make all` succeed for your changes? Was
+conformance testing successful on an Aarch64 machine?
+
+### License:
+
+By submitting this pull request, I confirm that my contribution is
+made under the terms of the Apache 2.0 license.

CONTRIBUTING.md

@@ -1,65 +1,47 @@
-# Contribution Guidelines
+# External Contribution Guidelines
 
-## Project status
+Thank you for your interest in contributing to LNSym! We greatly value
+feedback and contributions from the community. Please read this
+document before submitting any pull requests or issues.
 
-Amazon Confidential
+### Submitting a Pull Request
 
-LNSym is an Amazon-internal project. Please do not make any external
-contributions at this time.
+**Focused Changes**: Create small, focused PRs that address a single
+issue or implement a specific feature.
 
-### Test Your Contribution
+**Documentation**: Add relevant documentation and comments to your
+code.
 
-1. Start from a clean slate; remove previous build artifacts using
-   `make clean_all`.
+**Continuous Integration**: Please ensure that all CI checks pass on
+your PR. During development, you can test your contribution on your
+local machine by following the build instructions in the
+[README.md](https://github.com/leanprover/LNSym?tab=readme-ov-file#build-instructions).
 
-2. Follow the LNSym build instructions in the README.md (including
-   conformance testing on an Aarch64 machine) before submitting your
-   pull request.
+### Filing an Issue
 
-## FAQs
+When filing an issue, first check whether the same issue has already
+been reported previously by someone else. In your issue, include
+details like:
 
-### How do I add a new Arm instruction?
+- Illustrative, minimal, and reproducible test cases
+- Commit hash of LNSym that you used
+- Suggested modifications, if any
 
-1. **Decode:** Add support, if needed, for decoding the instruction's
-   class to LNSym's Arm decoder (function `decode_raw_inst` in
-   `Arm/Decode.lean`).  See Section C4.1 in Part A of the [Arm
-   manual's
-   PDF](https://developer.arm.com/documentation/ddi0487/latest) to
-   learn about Arm's instruction classes.
+### Licensing
 
-   An `ArmInst` type describes a fully-decoded Arm instruction. It
-   contains constructors that correspond to the currently supported
-   instruction classes. For example, the `DPI` constructor represents
-   the data processing (immediate) instructions, which have several
-   sub-classes which are formalized in `Arm/Decode/DPI/DPI.lean`.
+See the
+[LICENSE](https://github.com/leanprover/LNSym/blob/main/LICENSE) file
+for LNSym's licensing. All files in this project will be copyright
+only by "Amazon.com, Inc. or its affiliates". The PR template will
+prompt you to confirm the licensing of your contribution.
 
-2. **Instruction Semantics:** Formalize the instruction's behavior in
-   a file under an appropriate directory pertaining to the instruction
-   class (under `Arm/Insts`). You may either need to extend a
-   pre-existing function (perhaps it supported only a subset of the
-   instructions in that class, and you can add your new instruction
-   right there), or add a new directory/file/function altogether.
+### What to Expect
 
-   For example, `Arm/Insts/DPI/Add_sub_imm.lean` contains the
-   semantics of all instructions (e.g., `ADD`) under the `Add_sub_imm`
-   sub-class of data processsing (immediate) instructions.
+**Be Patient**: Reviewing your contribution may take some time!
 
-   Also add a function to generate random instructions of that class;
-   this will be used to validate the instruction semantics via
-   conformance testing. For an example, see the function
-   `Add_sub_imm_cls.rand` defined in the same file as the instruction
-   semantics. These functions should be eventually added to
-   `Insts.rand` in `Arm/Insts.lean`, which is used to run
-   co-simulations when `build/bin/lnsym` is executed.
+**Not All PRs Get Merged**: We value every contribution. However, to
+enable code maintainability and quality, we will merge only those PRs
+that align with our priorities and goals.
 
-   You do not need to know how these co-simulations are run, but an
-   interested reader can see `Arm/Cosim.lean` and `Arm/Main.lean` for
-   details.
-
-3. **Execute:** Add support, if needed, to execute this instruction by
-   extending the function `exec_inst` in `Arm/Exec.lean` .
-
-4. **Build and Test:** Run `make` to make sure nothing breaks as a
-   consequence of your addition. Also run `make cosim` on an Aarch64
-   machine to run conformance tests for validating your new
-   instruction.
+**Work in Progress**: LNSym is under development and things can change
+rapidly.

LICENSE

@@ -1,4 +1,70 @@
-Amazon Confidential
+Apache License 2.0 (Apache)
+Apache License
+Version 2.0, January 2004
+http://www.apache.org/licenses/
 
-LNSym is an Amazon-internal project. Please do not make any external
-contributions at this time.
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+1. Definitions.
+
+"License" shall mean the terms and conditions for use, reproduction, and distribution as defined by Sections 1 through 9 of this document.
+
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+
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+
+"You" (or "Your") shall mean an individual or Legal Entity exercising permissions granted by this License.
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+
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README.md

@@ -1,12 +1,7 @@
 # LNSym: Native Code Symbolic Simulator in Lean
 [![Makefile CI](https://github.com/leanprover/LNSym/actions/workflows/makefile.yml/badge.svg)](https://github.com/leanprover/LNSym/actions/workflows/makefile.yml)
 
-## Project status
-
-Amazon Confidential
-
-LNSym is an Amazon-internal project. Please do not make any external
-contributions at this time.
+LNSym is a symbolic simulator for Armv8 machine-code programs.
 
 ## Prerequisites
 

doc/add_new_inst.md

@@ -0,0 +1,50 @@
+# Adding a new Arm instruction
+
+Adding the semantics of a new Arm instruction is a good beginner task
+that can familiarize one with LNSym's ISA modeling design
+decisions. The following steps can help in getting started.
+
+1. **Decode:** Add support, if needed, for decoding the instruction's
+   class to LNSym's Arm decoder (function `decode_raw_inst` in
+   `Arm/Decode.lean`).  See Section C4.1 in Part A of the [Arm
+   manual's
+   PDF](https://developer.arm.com/documentation/ddi0487/latest) to
+   learn about Arm's instruction classes.
+
+   An `ArmInst` type describes a fully-decoded Arm instruction. It
+   contains constructors that correspond to the currently supported
+   instruction classes. For example, the `DPI` constructor represents
+   the data processing (immediate) instructions, which have several
+   sub-classes which are formalized in `Arm/Decode/DPI/DPI.lean`.
+
+2. **Instruction Semantics:** Formalize the instruction's behavior in
+   a file under an appropriate directory pertaining to the instruction
+   class (under `Arm/Insts`). You may either need to extend a
+   pre-existing function (perhaps it supported only a subset of the
+   instructions in that class, and you can add your new instruction
+   right there), or add a new directory/file/function altogether.
+
+   For example, `Arm/Insts/DPI/Add_sub_imm.lean` contains the
+   semantics of all instructions (e.g., `ADD`) under the `Add_sub_imm`
+   sub-class of data processsing (immediate) instructions.
+
+   Also add a function to generate random instructions of that class;
+   this will be used to validate the instruction semantics via
+   conformance testing. For an example, see the function
+   `Add_sub_imm_cls.rand` defined in the same file as the instruction
+   semantics. These functions should be eventually added to
+   `Insts.rand` in `Arm/Insts.lean`, which is used to run
+   co-simulations when `build/bin/lnsym` is executed.
+
+   You do not need to know how these co-simulations are run, but an
+   interested reader can see `Arm/Cosim.lean` and `Arm/Main.lean` for
+   details.
+
+3. **Execute:** Add support, if needed, to execute this instruction by
+   extending the function `exec_inst` in `Arm/Exec.lean` .
+
+4. **Build and Test:** Start from a clean slate to remove previous
+   build artifacts (`make clean_all`) and then run `make all` to make
+   sure nothing breaks as a consequence of your addition. Also run
+   `make cosim` on an Aarch64 machine to run conformance tests for
+   validating your new instruction.