[clang] Implement resource binding type prefix mismatch errors (PR #87578)

[Chris B via cfe-commits]

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@@ -7367,6 +7367,75 @@ static void handleHLSLResourceBindingAttr(Sema &S, Decl *D,
     return;
   }
 
+  VarDecl *VD = dyn_cast<VarDecl>(D);
+  HLSLBufferDecl *BD = dyn_cast<HLSLBufferDecl>(D);
+
+  if (VD || BD) {
+    llvm::hlsl::ResourceClass RC;
+    std::string varTy = "";
+    if (VD) {
+
+      const Type *Ty = VD->getType()->getPointeeOrArrayElementType();
+      if (!Ty)
+        return;
+      QualType t = ((ElaboratedType *)Ty)->getNamedType();
+      const CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
+      if (!RD)
+        return;
+
+      if (auto TDecl = dyn_cast<ClassTemplateSpecializationDecl>(RD))
+        RD = TDecl->getSpecializedTemplate()->getTemplatedDecl();
+      RD = RD->getCanonicalDecl();
+      const auto *Attr = RD->getAttr<HLSLResourceAttr>();
+      if (!Attr)
+        return;
+
+      RC = Attr->getResourceClass();
+      varTy = RD->getNameAsString();
+    } else {
+      if (BD->isCBuffer()) {
+        RC = llvm::hlsl::ResourceClass::CBuffer;
+        varTy = "cbuffer";
+      } else {
+        RC = llvm::hlsl::ResourceClass::CBuffer;
+        varTy = "tbuffer";
+      }
+    }
+    switch (RC) {
+    case llvm::hlsl::ResourceClass::SRV: {
+      if (Slot.substr(0, 1) != "t")
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llvm-beanz wrote:

Or we could replace all the `Slot.substr(0,1)` calls just with `Slot[0]` and compare characters instead of strings.

https://github.com/llvm/llvm-project/pull/87578