Support binding larger buffer ranges >2GB to shaders #6338

Hi,

I'd like to request support for binding buffer sizes in the 64bit range.

That currently seems to be constrained to 2GB.
A Dawn team member has advised me that this is a spec issue; see this Chromium issue. I haven't been able to pinpoint the constraint in the spec myself, but I am also not very familiar with it.

Related work that has already landed:

• Buffer indices are unsigned
• Max binding sizes use u64

Related issues:

• Allow storage buffer limits beyond i32 max as a native extension gfx-rs/wgpu#8105