[llvm] [SPIRV] Filter disallowed extensions for env (PR #150051)

[Steven Perron via llvm-commits]

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@@ -104,6 +167,26 @@ static const std::map<std::string, SPIRV::Extension::Extension, std::less<>>
         {"SPV_KHR_float_controls2",
          SPIRV::Extension::Extension::SPV_KHR_float_controls2}};
 
+/*
+
+TODO: std::set_union is not constexpr in c++17. I would still like a way to make
+sure the environment lists are added.
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s-perron wrote:

@michalpaszkowski Good idea, and if we don't do it now, we may not get to it later. I added a required environment field. And then we check that. This is more time consuming then the previous implementation, but it is not time critical. It is called once for every invocation of the backend.

What do you think?

https://github.com/llvm/llvm-project/pull/150051