kc3-lang/angle

2021-07-13T14:10:41

Vulkan: SPIR-V Gen: Assignment between mismatching SPIR-V types In general, GLSL qualifiers translate to SPIR-V decorations on SPIR-V variables. In the case of blocks (struct or interface block), OpMemberDecorate is used, which due to its specification in SPIR-V, can only apply decorations to direct members of a block. This makes it impossible for example to decorate a nested member of a block through its variable id. As such, some decorations such as RowMajor and Invariant apply to members of a block given its _type_ id. Unfortunately SPIR-V requires ArrayStride to also be applied to a type directly, rather than a member of a block. This implies that some types, such as structs used in uniform/buffer interface block, or decorated with invariant or row_major, as well as arrays (of any type) used inside and outside interface blocks to produce different SPIR-V types from the same GLSL type. The SpirvTypeSpec data previously introduced specialize these types. It's necessary to "cast" between these types when needed. The translator handles casts at load/store boundary: - Upon load, the value is cast to the type with the default SpirvTypeSpec. - Upon store, the value is cast from the default to the store target SpirvTypeSpec. - All intermediate results use the default SpirvTypeSpec. Bug: angleproject:4889 Change-Id: I6fa28e518ec6b517ff163f44b6892859eb4b10fd Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3026145 Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Tim Van Patten <timvp@google.com> Reviewed-by: Jamie Madill <jmadill@chromium.org>