1601060 - Failed to compile shader due to integer overflow

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect, P3)

Description

[Andrew Osmond [:aosmond] (he/him)]

On my Z3C running LineageOS 16 (Android 9), Adreno 330, OpenGL ES 3.0 V@140.0, when I attempt to enable WebRender, I get the following shader compilation error:

Failed to compile shader: brush_solid
Vertex shader compilation failed.
ERROR: 0:792: '0xffff0000' : Integer overflow
ERROR: 0:792: '0xffff0000' : Syntax error
2 compilation errors. No code generated.

Repeated for each of the shaders. It appears it doesn't like the high bit being set for a signed integer. It is easy enough to fix however if we just do >> 16 instead of the mask and adjust the shaders that check instance.flags appropriately.

Comment 1

[Andrew Osmond [:aosmond] (he/him)]

try: https://treeherder.mozilla.org/#/jobs?repo=try&revision=d68514fc41f8934d8e58d183ab6017ae062d59bb

Comment 2

[Andrew Osmond [:aosmond] (he/him)]

Attachment: Bug 1601060 - Fix shader compilation error on some Android devices.

Some OpenGL ES implementations do not like how we overflow a signed
32-bit integer when masking what are otherwise really unsigned 32-bit
integers. This patch avoids the problematic mask and instead just
does an equivalent shift.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/35d6558a2145
Fix shader compilation error on some Android devices. r=nical

Comment 4

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/35d6558a2145

Comment 5

[Ryan VanderMeulen [:RyanVM]]

Does this need a Beta approval request?

Comment 6

[Andrew Osmond [:aosmond] (he/him)]

I don't think so. We are only shipping WR on Android to the Pixel 2 and it seems to be fine.