Minifying Renderscript code: huge performance drop when upgrading AGP from 7.3.1 to 7.4.0 [267990059]

Verified

Bug

Status Update

No update yet.

Description

bv...@gmail.com

created issue #1

Feb 6, 2023 09:26AM

We're using Renderscript in one of our projects and noticed that our build times for a minified release build went up by a factor of 3 after upgrading the Android Gradle Plugin from 7.3.1 to 7.4.0: from 17 minutes to 53 minutes.

For each Renderscript file, two files are generated: a ScriptC_$name file which contains bridging functions, and a $nameBitCode file which contains a few huge byte arrays that are compiled into GPU code on the user's phone. R8 takes a very long time to process this last file.

I made a sample project here: https://github.com/bvschaik/r8-renderscript-minify-issue
This project contains a copy of the BitCode class that's generated by Renderscript here.

Using AGP 7.4.0 (uses R8 4.0.48), running assembleRelease on this project takes almost 4 minutes, with 3m40s taken up by the minifyReleaseWithR8 task.

Downgrading AGP to 7.3.1 (uses R8 3.3.83), the minifyReleaseWithR8 "only" takes 1m10s, which is still quite long for processing some static byte arrays.

For now we're forcing R8 to the last available 3.3 version to get back to acceptable build times.

What could cause this increase in build times?
Why is R8 spending so much time on relatively simple code?
What can we do to tell R8 "don't change anything in this file"? I tried various -keep rules but it didn't make a difference.

Comments

ch...@google.com <ch...@google.com> Feb 6, 2023 09:35AM

Reassigned to ch...@google.com.

ch...@google.com <ch...@google.com> #2Feb 7, 2023 07:57AM

Thank you for the report and the supplied dump with the reproduction. I can confirm that the NPE is also present on HEAD, and I will look into it.

Quite a few of the class files in the dump has malformed inner-class attribute, where R8 reports e.g.:

Info in /tmp/tmpo67ucguh/program.jar:ofifmwrrhhmodsc/ψξψξψξξ.class:
Malformed inner-class attribute:
	outerTypeInternal: ofifmwrrhhmodsc/ψξψξψξξ
	innerTypeInternal: ofifmwrrhhmodsc/ψξψξψξξ$ψξξψξξξ
	innerName: ψξψξψξξ$ψξξψξξξ

These are ignored, so they should not be the reason for the NPE, but something to also look into.

ap...@google.com <ap...@google.com> #3Feb 8, 2023 11:31AM

Project: r8
Branch: main

commit e59500ca4445f5fb5d2ccc1114acbf66df11d196
Author: Søren Gjesse <sgjesse@google.com>
Date: Tue Mar 21 09:48:55 2023

Insert patched frame instructions in the right place

Fixes:

Issue 267990059

Description

Issue summary

Comments

ch...@google.com <ch...@google.com> Feb 6, 2023 09:35AM

ch...@google.com <ch...@google.com> #2Feb 7, 2023 07:57AM

ap...@google.com <ap...@google.com> #3Feb 8, 2023 11:31AM

ap...@google.com <ap...@google.com> #4Feb 8, 2023 02:53PM

ap...@google.com <ap...@google.com> #5Feb 8, 2023 03:16PM

ap...@google.com <ap...@google.com> #6Feb 9, 2023 10:06AM

ap...@google.com <ap...@google.com> #7Feb 9, 2023 10:27AM

ap...@google.com <ap...@google.com> #8Feb 9, 2023 10:27AM

ap...@google.com <ap...@google.com> #9Feb 9, 2023 10:27AM

ap...@google.com <ap...@google.com> #10Feb 9, 2023 10:27AM

ap...@google.com <ap...@google.com> #11Feb 9, 2023 10:27AM

ap...@google.com <ap...@google.com> #12Feb 9, 2023 10:30AM

ap...@google.com <ap...@google.com> #13Feb 9, 2023 10:30AM

ap...@google.com <ap...@google.com> #14Feb 9, 2023 10:30AM

ap...@google.com <ap...@google.com> #15Feb 9, 2023 10:30AM

ap...@google.com <ap...@google.com> #16Feb 9, 2023 10:30AM

ch...@google.com <ch...@google.com> #17Feb 9, 2023 10:34AM

bv...@gmail.com <bv...@gmail.com> #18Feb 9, 2023 12:15PM

ch...@google.com <ch...@google.com> #19Feb 9, 2023 02:24PM

Add comment

Issue metadata