A 'fake' WebGPU implementation to test CPU WGSL implementations.

where naga fails:

• declaring variables that shadow predeclared types (is now allowed by wgsl)
  • webgpu:shader,validation,parse,shadow_builtins:*
• declaring variables with reserved names (is not allowed by wgsl)
• shadowing errors
  • var read : i32; var<storage, read> a: i32; => webgpu:shader,validation,parse,shadow_builtins:shadow_hides_access_mode
  • let atomicLoad = 4; _ = atomicLoad(&a); => webgpu:shader,validation,parse,shadow_builtins:shadow_hides_builtin_atomic
• textureBarrier() not implemented?
  • webgpu:shader,validation,parse,shadow_builtins:shadow_hides_builtin_barriers
• textureGather() only accepts vecN<f32> coords
  • webgpu:shader,validation,parse,shadow_builtins:shadow_hides_builtin_texture
  • seems to be a regression in v22 => v23
  • overall, it seems that naga does not perform any implicit conversions for builtin function calls.

cd cts/ clear && node ./tools/run_node --colors --gpu-provider (realpath ../wesl-cpu/) 'webgpu:shader,validation,parse,*'

get wesl-web from the playground wasm-pack build wesl-web --dev --target deno --out-dir path/to/wesl-cts/wesl-cpu/wesl-web --no-default-features --features debug