[clang] [Clang][HLSL] Add environment parameter to availability attribute (PR #89809)

[Helena Kotas via cfe-commits]

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@@ -18,14 +18,21 @@ namespace hlsl {
 
 #define _HLSL_BUILTIN_ALIAS(builtin)                                           \
   __attribute__((clang_builtin_alias(builtin)))
-#define _HLSL_AVAILABILITY(environment, version)                               \
-  __attribute__((availability(environment, introduced = version)))
+#define _HLSL_AVAILABILITY(platform, version)                                  \
+  __attribute__((availability(platform, introduced = version)))
+#define _HLSL_AVAILABILITY_STAGE(platform, version, stage)                     \
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hekota wrote:

I believe all of the intrinsics implemented so far are available for all shader stages, so no update is needed.

https://github.com/llvm/llvm-project/pull/89809