Translate LLVM-IR zero-length arrays to 1-length arrays in SPIR-V #2743
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Why would this be non-conformant SPIR-V? |
My apologies, I completely misread your initial description. Lowering to a SPIR-V array of length 1 is of course valid SPIR-V. |
…rray of length 1 (#15663) Cherry-pick of KhronosGroup/SPIRV-LLVM-Translator#2743. The LLVM-IR type of zero-length array does not seem to have a mapping into SPIR-V type, rather it outputs an error since the obvious choice of zero-length array is not valid in SPIR-V. This, for example, prohibits us from using unbounded arrays in SYCL device kernels because they are typically represented in LLVM-IR through zero-length arrays. This PR introduces a workaround to this by lowering a zero-length array in LLVM-IR to a 1-length array in SPIR-V.
The LLVM-IR type of zero-length array does not seem to have a mapping into SPIR-V type, rather it outputs an error since the obvious choice of zero-length array is not valid in SPIR-V. This, for example, prohibits us from using unbounded arrays in SYCL device kernels because they are typically represented in LLVM-IR through zero-length arrays. This PR attempts to introduce a workaround to this by lowering a zero-length array in LLVM-IR to a 1-length array in SPIR-V.