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

[Matt Arsenault via cfe-commits]

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@@ -0,0 +1,39 @@
+// REQUIRES: amdgpu-registered-target
+
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -target-cpu gfx9-4-generic -verify -emit-llvm -o - %s
+
+typedef unsigned int uint;
+
+typedef float  v2f   __attribute__((ext_vector_type(2)));
+typedef float  v4f   __attribute__((ext_vector_type(4)));
+typedef float  v16f  __attribute__((ext_vector_type(16)));
+typedef int    v2i   __attribute__((ext_vector_type(2)));
+typedef int    v4i   __attribute__((ext_vector_type(4)));
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arsenm wrote:

Use normal float2/int2 style names? 

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