| commit | f083c97232d78b04b828d5ccf7f505b152871a10 | [log] [tgz] |
|---|---|---|
| author | Renaud Kauffmann <rkauffmann@nvidia.com> | Thu Dec 05 18:36:48 2024 -0800 |
| committer | Copybara-Service <copybara-worker@google.com> | Thu Dec 05 18:40:45 2024 -0800 |
| tree | db3a442d5b3cc3b0214772da97bf05caf431390a | |
| parent | 2885de6fa2dc09d161d3cad39aaf32998882b84f [diff] |
[flang][cuda] Distinguish constant fir.global from globals with a #cuf.cuda<constant> attribute (#118912)
1. In `CufOpConversion` `isDeviceGlobal` was renamed
`isRegisteredGlobal` and moved to the common file. `isRegisteredGlobal`
excludes constant `fir.global` operation from registration. This is to
avoid calls to `_FortranACUFGetDeviceAddress` on globals which do not
have any symbols in the runtime. This was done for
`_FortranACUFRegisterVariable` in #118582, but also needs to be done
here after #118591
2. `CufDeviceGlobal` no longer adds the `#cuf.cuda<constant>` attribute
to the constant global. As discussed in #118582 a module variable with
the #cuf.cuda<constant> attribute is not a compile time constant. Yet,
the compile time constant also needs to be copied into the GPU module.
The candidates for copy to the GPU modules are
- the globals needing regsitrations regardless of their uses in device
code (they can be referred to in host code as well)
- the compile time constant when used in device code
3. The registration of "constant" module device variables (
#cuf.cuda<constant>) can be restored in `CufAddConstructor`
GitOrigin-RevId: 27e458c8cbec27d48ee73623c4b5bbf6bba407cb
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