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Explicit types in cbuffer layouts #156919
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f6008b3
[DirectX] Add 32- and 64-bit 3-element vectors to DataLayout
bogner b0b2529
[DirectX] Introduce `dx.Padding` type
bogner a832f68
[AST] Give `CharUnits::operator%` a consistent type. NFC
bogner 9d3ee22
[DirectX] Make a test a bit more readable. NFC
bogner 5797e18
[DirectX] Fix crash when naming buffers of arrays
bogner 030d8cb
wip: Update DXILCBufferAccess to padding approach
bogner 29843c0
wip: Explicit structs in clang codegen
bogner c73d2a3
[DirectX] Drop dx.Layout extension type
bogner 92bd225
wip: Index into padded arrays
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Doing an i8 gep does work for SPIR-V. We want to avoid that as much as possible. Can this be turned into a typed GEP with the padded type when needed? I tried writing it myself so I could make a suggestion, but I can't get it right.
See https://discourse.llvm.org/t/type-based-gep-plans/87183/14
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@bogner You are still generating this GEP with an i8. Can we change this to a GEP on the array type.
Start with the test at the end. Compile with
clang-dxc test_minimal_peeling.hlsl -T cs_6_8 -spirv -fcgl
The access to myArray is:
It would be better if it could be
You use the original array size with the padding.
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I've tried this out in 92bd225 (which still needs test updates). This looks mostly reasonable with the caveat that we do need a bit of a fictional type for this to work (the array with padding on all elements including the last one). Since we don't actually read the padding this is probably fine.