[LLVM-C] Add an accessor for the kind of a Metadata Node

Summary: Allows for retrieving the type of a metadata node.  Has the added benefit of ensuring that the C and C++ kind APIs stay in sync as a failure to add a corresponding LLVMMetadataKind will result in the switch in the accessor being semantically malformed.

Reviewers: whitequark, deadalnix

Reviewed By: whitequark

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D52693

llvm-svn: 343469

llvm/include/llvm-c/DebugInfo.h

@@ -126,6 +126,44 @@ typedef enum {
     LLVMDWARFEmissionLineTablesOnly
 } LLVMDWARFEmissionKind;
 
+/**
+ * The kind of metadata nodes.
+ */
+enum {
+  LLVMMDStringMetadataKind,
+  LLVMConstantAsMetadataMetadataKind,
+  LLVMLocalAsMetadataMetadataKind,
+  LLVMDistinctMDOperandPlaceholderMetadataKind,
+  LLVMMDTupleMetadataKind,
+  LLVMDILocationMetadataKind,
+  LLVMDIExpressionMetadataKind,
+  LLVMDIGlobalVariableExpressionMetadataKind,
+  LLVMGenericDINodeMetadataKind,
+  LLVMDISubrangeMetadataKind,
+  LLVMDIEnumeratorMetadataKind,
+  LLVMDIBasicTypeMetadataKind,
+  LLVMDIDerivedTypeMetadataKind,
+  LLVMDICompositeTypeMetadataKind,
+  LLVMDISubroutineTypeMetadataKind,
+  LLVMDIFileMetadataKind,
+  LLVMDICompileUnitMetadataKind,
+  LLVMDISubprogramMetadataKind,
+  LLVMDILexicalBlockMetadataKind,
+  LLVMDILexicalBlockFileMetadataKind,
+  LLVMDINamespaceMetadataKind,
+  LLVMDIModuleMetadataKind,
+  LLVMDITemplateTypeParameterMetadataKind,
+  LLVMDITemplateValueParameterMetadataKind,
+  LLVMDIGlobalVariableMetadataKind,
+  LLVMDILocalVariableMetadataKind,
+  LLVMDILabelMetadataKind,
+  LLVMDIObjCPropertyMetadataKind,
+  LLVMDIImportedEntityMetadataKind,
+  LLVMDIMacroMetadataKind,
+  LLVMDIMacroFileMetadataKind
+};
+typedef unsigned LLVMMetadataKind;
+
 /**
  * An LLVM DWARF type encoding.
  */
@@ -1153,6 +1191,13 @@ LLVMMetadataRef LLVMGetSubprogram(LLVMValueRef Func);
  */
 void LLVMSetSubprogram(LLVMValueRef Func, LLVMMetadataRef SP);
 
+/**
+ * Obtain the enumerated type of a Metadata instance.
+ *
+ * @see llvm::Metadata::getMetadataID()
+ */
+LLVMMetadataKind LLVMGetMetadataKind(LLVMMetadataRef Metadata);
+
 #ifdef __cplusplus
 } /* end extern "C" */
 #endif

llvm/lib/IR/DebugInfo.cpp

@@ -1354,3 +1354,14 @@ LLVMMetadataRef LLVMGetSubprogram(LLVMValueRef Func) {
 void LLVMSetSubprogram(LLVMValueRef Func, LLVMMetadataRef SP) {
   unwrap<Function>(Func)->setSubprogram(unwrap<DISubprogram>(SP));
 }
+
+LLVMMetadataKind LLVMGetMetadataKind(LLVMMetadataRef Metadata) {
+  switch(unwrap(Metadata)->getMetadataID()) {
+#define HANDLE_METADATA_LEAF(CLASS) \
+  case Metadata::CLASS##Kind: \
+    return (LLVMMetadataKind)LLVM##CLASS##MetadataKind;
+#include "llvm/IR/Metadata.def"
+  default:
+    return (LLVMMetadataKind)LLVMGenericDINodeMetadataKind;
+  }
+}