Commit aa2626f966b37cbfb82ca8e9ec343c1933d671ba
2021-05-21T15:24:55
Vulkan: SPIR-V Gen: Handle load/store access chain This change implements a key instruction of SPIR-V, OpAccessChain. Inspired by glslang's implementation, a class is added (AccessChain) that tracks "indices" into a base value. These indices could select a field of a block, an element of an array, a column of a matrix, or a component of a vector. Nuances (such as multi-component swizzle as an lvalue not representable in SPIR-V) and optimizations (such as all-literal indices to an rvalue) that are implemented in glslang have also been implemented in this change. As a result, this change implements all manners of loads and stores (with the exception of this gotcha: https://github.com/KhronosGroup/glslang/issues/2637). The change uses this feature to translate the basic shader which does `gl_Position = positionAttr;` (by implementing EOpAssign), and enables a test that uses this shader. Bug: angleproject:4889 Change-Id: I22dbe5b169ce499eaac657902164aca3b0ebc193 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2911880 Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Tim Van Patten <timvp@google.com>