RenderScriptPrebuilts.md

Updating RenderScript
=====================

For the latest version of this doc, please make sure to visit:
[Android RenderScript Prebuilts Doc](https://android.googlesource.com/platform/external/clang/+/dev/RenderScriptPrebuilts.md)

Updating LLVM Libraries
-----------------------

Loop over llvm, clang, compiler-rt (in this order):

1. Do a squashed merge of *aosp/dev* to *aosp/master*.

        repo start update .
        git fetch aosp dev
        git merge --squash aosp/dev
        git commit -a
        repo upload .

2. Test everything before submitting the patch from the previous step.

3. Grab the squashed commit and replay it in *aosp/dev*.

        repo sync .
        git remote update
        git branch -D clean_master
        git checkout -b clean_master aosp/master
        git checkout working_dev

    Use `-s ours` to ensure that we skip the squashed set of changes.
    If/when we forget this, we have to do it later.

        git merge -s ours clean_master
        git push aosp refs/heads/working_dev:refs/heads/dev
        git branch -D clean_master

4. Clean up after our working branch.

        git checkout --detach
        git branch -D working_dev

This works better because we can keep full history in *aosp/dev*, while
maintaining easy reverts/commits through *aosp/master*.


Generating New Prebuilts
------------------------

1. Set RS_LLVM_PREBUILTS_VERSION in build/core/clang/config.mk to the latest
   prebuilts generated for this rebase, or to the latest platform version if no
   new prebuilts were generated.
2. Iteratively attempt to build the platform and fix any API differences in
   frameworks/compile/slang, and/or frameworks/compile/libbcc. This may entail
   updating the various snapshots of Bitcode Readers/Writers.
3. Update RenderScript prebuilts.

        cd $ANDROID_BUILD_TOP/frameworks/rs
        ./update_rs_prebuilts.sh

4. The prebuilts get copied to **prebuilts/sdk**, so we must upload the
relevant bits from there.

        cd $ANDROID_BUILD_TOP/prebuilts/sdk
        git commit -a
        repo upload .

5. Submit CLs.


Testing Checklist
-----------------

1. Go to **external/llvm** and run `./android_test.sh` (no known failures
as of 2015-10-08).
2. Ensure successful build for all architectures: 32- and 64- bit ARM, x86 and
Mips.
3. Run 32- and 64- bit RenderScript CTS at least for ARM and AArch64.
4. Test RenderScript apps: RsTest, ImageProcessing, and finally
RSTest\_Compatlib in compatibility mode.
5. Test old APKs with rebased tools: grab the above apps from a different tree
(i.e. without the rebase), push them to a device with the rebased tools, and
test.
This ensures that the rebased BitcodeReader can read the output of old
BitcodeWriters.
6. Test new APKs on an old device: test freshly built APKs for
RSTest\_V{11,14,16}, and ImageProcessing\_2 on an old device (say Manta) and
ensure they pass.
This ensures that the rebase did not break the 2.9 and 3.2 BitcodeWriters.


Checklist for CLs
-----------------

The following projects will almost always have CLs as a part of the rebase.
Depending on the changes in LLVM, there might be updates to other projects as
well.

* External projects

  * **external/clang**
  * **external/compiler-rt**
  * **external/llvm**
  * **frameworks/compile/mclinker**

* RenderScript projects

  * **frameworks/compile/libbcc**
  * **frameworks/compile/slang**
  * **frameworks/rs**

* Prebuilts
  * **prebuilts/sdk**

* CTS tests

  * **cts/tests/tests/renderscript**
  * **cts/tests/tests/renderscriptlegacy**
  * **cts/tests/tests/rscpp**