In HIP, dynamic LDS variables are represented using `0-element` global
arrays in the `__shared__` language address-space.
```cpp
extern __shared__ int LDS[];
```
These are not representable in SPIRV directly.
To represent them, for AMD, we use an array with `UINT32_MAX`-elements.
These are reverse translated to 0-element arrays later in AMD's SPIRV
runtime pipeline (in
[SPIRVReader.cpp](8cb74e264d/lib/SPIRV/SPIRVReader.cpp (L358))).
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