kc3-lang/angle

2019-12-16T16:07:04

Use TSpan for TType's array sizes Until C++20, std::vector doesn't have a constexpr constructor, which means TType cannot use a `TVector` for `mArraySizes` if an arrayed type needs to be created constexpr. This is needed for the upcoming textureGatherOffsets implementation. A new TSpan class is introduced, based on std::span (from C++20) that holds the pointer/size allocated from a TVector without owning it. Since TVector's allocation are made from a pool, the allocated memory will live beyond the vector's destruction. `TType::mArraySizes` is changed to this type. This change will allow a new constexpr constructor to be added to TType that takes a TSpan as array directly, a value which is constexpr initialized from a static array (instead of TVector). Bug: angleproject:3569 Change-Id: I78793b0f4c64519e0ebe30cf6e0de995ba70035d Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1968260 Reviewed-by: Jiajia Qin <jiajia.qin@intel.com> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>