[clang] [clang][X86] Support __attribute__((model("small"/"large"))) (PR #124834)

[Artem Belevich via cfe-commits]

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@@ -5,7 +5,7 @@
 // RUN: %clang_cc1 -triple riscv64 -verify=expected,riscv64 -fsyntax-only %s
 // RUN: %clang_cc1 -triple x86_64 -verify=expected,x86_64 -fsyntax-only %s
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Artem-B wrote:

nvptx does not *use* the code models, but CUDA compilation will *see* those attribute in the host code in the same TU. The main goal here is to make sure the GPU-side compilation will not be broken.  I guess it may need a separate test under test/SemaCUDA/ where we have things set up to run a CUDA compilation.
You could use RUN lines in ["test/SemaCUDA/function-target.cu"](https://github.com/llvm/llvm-project/blob/d3161defd6b717241a85b6ca528754c747060735/clang/test/SemaCUDA/function-target.cu#L1)  as the base and the same content as you have in clang/test/CodeGen/X86/codemodel.cpp

https://github.com/llvm/llvm-project/pull/124834