[clang] [clang][HIP] Make some math not not work with AMDGCN SPIR-V (PR #128360)

[Alex Voicu via cfe-commits]

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@@ -14,6 +14,12 @@
 #include "hip/hip_version.h"
 #endif // __has_include("hip/hip_version.h")
 
+#ifdef __SPIRV__
+#define __PRIVATE_AS __attribute__((address_space(0)))
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AlexVlx wrote:

Acknowledged, but the header was already using numbered address spaces (ROCDL is also using numbered rather than generic), and I really don't want to take on fixing the general badness living here/there. We shouldn't be using explicit ASes at all in what is supposed to be a generic interface, but that's a different kettle of fish. I'd like to keep this simple and land it, if possible, within the backport window as it's a hard break for us at the moment.

https://github.com/llvm/llvm-project/pull/128360