Bug 223096

Summary:

[GPU Process] Encoding buffer for DisplayList items should be aligned to 8 bytes

Product:

WebKit

Reporter:

Said Abou-Hallawa <sabouhallawa>

Component:

Canvas

Assignee:

Said Abou-Hallawa <sabouhallawa>

Status:

RESOLVED FIXED

Severity:

Normal

CC:

dino, ggaren, simon.fraser, thorton, webkit-bug-importer, wenson_hsieh

Priority:

Keywords:

InRadar

Version:

WebKit Nightly Build

Hardware:

Unspecified

OS:

Unspecified

Bug Depends on:

Bug Blocks:

222835

Attachments:

Description	Flags
Patch	none
Patch	simon.fraser: review+, ews-feeder: commit-queue-
Patch	ews-feeder: commit-queue-
Patch	none
Patch	ews-feeder: commit-queue-
Patch	none

Said Abou-Hallawa

Reported 2021-03-11 15:43:33 PST

ItemBuffer::append() allocates a static buffer whose size = sizeof(DisplayList::Item) + uint64_t for the DisplayList::ItemType. But this static buffer is of type uint8_t. So this array should be aligned to the alignment of a single uint8_t which is 1. The expectation is to have this buffer aligned to 8 bytes so all each member in the encoded DisplayList::Item can be aligned to its alignment requirement. This was caught on Apple Silicon when trying to enable GPU rendering for 2D canvas for layout tests. See https://build.webkit.org/#/builders/103/builds/88. But the same assertion fires if the same page is just opened in mini browser while GPU rendering for 2D canvas is enabled.

Attachments
Patch (1.99 KB, patch) 2021-03-11 15:49 PST, Said Abou-Hallawa	no flags	Details Formatted Diff Diff
Patch (1.88 KB, patch) 2021-03-11 16:14 PST, Said Abou-Hallawa	simon.fraser: review+ ews-feeder: commit-queue-	Details Formatted Diff Diff
Patch (2.06 KB, patch) 2021-03-11 17:14 PST, Said Abou-Hallawa	ews-feeder: commit-queue-	Details Formatted Diff Diff
Patch (2.06 KB, patch) 2021-03-11 17:55 PST, Said Abou-Hallawa	no flags	Details Formatted Diff Diff
Patch (2.06 KB, patch) 2021-03-11 18:57 PST, Said Abou-Hallawa	ews-feeder: commit-queue-	Details Formatted Diff Diff
Patch (2.01 KB, patch) 2021-03-11 20:59 PST, Said Abou-Hallawa	no flags	Details Formatted Diff Diff
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