[clang] [llvm] [AMDGPU] Introduce a new generic target `gfx9-4-generic` (PR #115190)

[Matt Arsenault via cfe-commits]

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@@ -156,6 +157,8 @@ StringRef llvm::AMDGPU::getArchFamilyNameAMDGCN(GPUKind AK) {
   switch (AK) {
   case AMDGPU::GK_GFX9_GENERIC:
     return "gfx9";
+  case AMDGPU::GK_GFX9_4_GENERIC:
+    return "gfx9";
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arsenm wrote:

I guess it would still be gfx9 (not that I think these type of macros are useful) 

https://github.com/llvm/llvm-project/pull/115190