[clang] [llvm] [HLSL][RootSignature] Implement Parsing of Descriptor Tables (PR #122982)

[Finn Plummer via cfe-commits]

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@@ -306,4 +307,254 @@ TEST_F(ParseHLSLRootSignatureTest, InvalidLexRegNumberTest) {
   ASSERT_FALSE(Consumer->IsSatisfied());
 }
 
+// Valid Parser Tests
+
+TEST_F(ParseHLSLRootSignatureTest, ValidParseEmptyTest) {
+  const llvm::StringLiteral Source = R"cc()cc";
+
+  TrivialModuleLoader ModLoader;
+  auto PP = CreatePP(Source, ModLoader);
+  auto TokLoc = SourceLocation();
+
+  hlsl::RootSignatureLexer Lexer(Source, TokLoc, *PP);
+  SmallVector<RootElement> Elements;
+  hlsl::RootSignatureParser Parser(Elements, Lexer, Diags);
+
+  // Test no diagnostics produced
+  Consumer->SetNoDiag();
+
+  ASSERT_FALSE(Parser.Parse());
+  ASSERT_EQ((int)Elements.size(), 0);
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inbelic wrote:

Updated this and other casting to use the `u` notation on the literals

https://github.com/llvm/llvm-project/pull/122982