Add check for invalid use of modifiers. (#3402)

* Add check for invalid use of modifiers.

* Fixes.

* Add test.

---------

Co-authored-by: Yong He <yhe@nvidia.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/source/slang/slang-ast-modifier.cpp b/source/slang/slang-ast-modifier.cpp
index 84046a601..ba30a547d 100644
--- a/source/slang/slang-ast-modifier.cpp
+++ b/source/slang/slang-ast-modifier.cpp
@@ -10,4 +10,16 @@ const OrderedDictionary<DeclRefBase*, SubtypeWitness*>& DifferentiableAttribute:
         m_mapToIDifferentiableWitness.add(m_typeToIDifferentiableWitnessMappings[i].key, m_typeToIDifferentiableWitnessMappings[i].value);
     return m_mapToIDifferentiableWitness;
 }
+
+void printDiagnosticArg(StringBuilder& sb, Modifier* modifier)
+{
+    if (!modifier)
+        return;
+    if (modifier->keywordName && modifier->keywordName->text.getLength())
+        sb << modifier->keywordName->text;
+    if (auto hlslSemantic = as<HLSLSemantic>(modifier))
+        sb << hlslSemantic->name.getContent();
+    return;
+}
+
 } // namespace Slang