[clang] Implement resource binding type prefix mismatch diagnostic infrastructure (PR #97103)

[Joshua Batista via cfe-commits]

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@@ -1,9 +1,10 @@
 // RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -o - -fsyntax-only %s -verify
 
-// expected-error at +1 {{invalid resource class specifier 'c' used; expected 'b', 's', 't', or 'u'}}
-float a : register(c0, space1);
+// valid, The register keyword in this statement isn't binding a resource, rather it is
+// specifying a constant register binding offset within the $Globals cbuffer, which is legacy behavior from DX9.
+float a : register(c0);
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bob80905 wrote:

I've added a test case to this file to test this.

https://github.com/llvm/llvm-project/pull/97103