[clang] [Clang][AMDGPU] Add a new builtin type for buffer rsrc (PR #94830)

[Matt Arsenault via cfe-commits]

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@@ -2201,6 +2207,9 @@ TypeInfo ASTContext::getTypeInfoImpl(const Type *T) const {
     Align = 8;                                                                 \
     break;
 #include "clang/Basic/WebAssemblyReferenceTypes.def"
+    case BuiltinType::AMDGPUBufferRsrc:
+      Width = 0;
+      Align = 256;
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arsenm wrote:

If we expose this as a pointer there are a lot of sharp edges we need to fix. If we expose it as an opaque type for builtins, the broken cases are hidden from end users. 

https://github.com/llvm/llvm-project/pull/94830