[clang] [llvm] [HLSL] Add handling of Interpolation Modifiers (PR #225452)

[Finn Plummer via cfe-commits]

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@@ -0,0 +1,6 @@
+// RUN: %clang_cc1 -x c++ -verify %s
+// RUN: %clang_cc1 -x c -verify %s
+// expected-no-diagnostics
+
+// Interpolation modifiers are keywords only in HLSL.
+int nointerpolation, linear, centroid, noperspective, sample, center;
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inbelic wrote:

These just become regular variable names

https://github.com/llvm/llvm-project/pull/225452