WebGPU issue with unpack4x8unorm on Safari Technology Preview 185

Hi,

With Safari Technology Preview Release 185 (Safari 17.4, WebKit 19618.1.9.8) the compiler seems to struggle with unpack4x8unorm() instruction (at least). https://www.w3.org/TR/WGSL/#unpack4x8unorm-builtin

Repro code: https://skal65535.github.io/webgpu/bug_unpack.html

This modified version of 'hello triangle' should display a single triangle but doesn't. Uncommenting line 51 makes the triangle appear.

Actually, adding the instruction:

_ = unpack4x8unorm(0xdeadbeef);

anywhere in the code triggers the bug, no matter if the line is used or not.

Tested on a MacBook Pro M1 Sonoma 14.2.1 (23C71)

Works fine with Chrome 120.0.6099.109 (Official Build) (arm64)

Thank you for the report. I filed https://bugs.webkit.org/show_bug.cgi?id=266871 to track this issue.

Safari Technology Preview Release 185 contains an early developer preview of WebGPU and most, but not all, of the standard functions are implemented. The unpack4x8unorm function will be added to a future release of Safari Technology Preview.

WebGPU issue with unpack4x8unorm on Safari Technology Preview 185
 
 
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