[LLVM-C] Deprecate the LLVMValueRef-returning metadata creation functions

Summary: There is still some value in using these functions while the remaining LLVMValueRef-based accessors are still around, but LLVMMDNodeInContext in particular has some wonky semantics that make it worth replacing outright.

Reviewers: whitequark, deadalnix

Reviewed By: whitequark

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60524

llvm-svn: 359114

Author: CodaFi

llvm/include/llvm-c/Core.h

@@ -2735,34 +2735,23 @@ void LLVMRemoveGlobalIFunc(LLVMValueRef IFunc);
  */
 
 /**
- * Obtain a MDString value from a context.
+ * Create an MDString value from a given string value.
  *
- * The returned instance corresponds to the llvm::MDString class.
+ * The MDString value does not take ownership of the given string, it remains
+ * the responsibility of the caller to free it.
  *
- * The instance is specified by string data of a specified length. The
- * string content is copied, so the backing memory can be freed after
- * this function returns.
+ * @see llvm::MDString::get()
  */
-LLVMValueRef LLVMMDStringInContext(LLVMContextRef C, const char *Str,
-                                   unsigned SLen);
-
-/**
- * Obtain a MDString value from the global context.
- */
-LLVMValueRef LLVMMDString(const char *Str, unsigned SLen);
+LLVMMetadataRef LLVMMDStringInContext2(LLVMContextRef C, const char *Str,
+                                       size_t SLen);
 
 /**
- * Obtain a MDNode value from a context.
+ * Create an MDNode value with the given array of operands.
  *
- * The returned value corresponds to the llvm::MDNode class.
+ * @see llvm::MDNode::get()
  */
-LLVMValueRef LLVMMDNodeInContext(LLVMContextRef C, LLVMValueRef *Vals,
-                                 unsigned Count);
-
-/**
- * Obtain a MDNode value from the global context.
- */
-LLVMValueRef LLVMMDNode(LLVMValueRef *Vals, unsigned Count);
+LLVMMetadataRef LLVMMDNodeInContext2(LLVMContextRef C, LLVMMetadataRef *MDs,
+                                     size_t Count);
 
 /**
  * Obtain a Metadata as a Value.
@@ -2804,6 +2793,17 @@ unsigned LLVMGetMDNodeNumOperands(LLVMValueRef V);
  */
 void LLVMGetMDNodeOperands(LLVMValueRef V, LLVMValueRef *Dest);
 
+/** Deprecated: Use LLVMMDStringInContext2 instead. */
+LLVMValueRef LLVMMDStringInContext(LLVMContextRef C, const char *Str,
+                                   unsigned SLen);
+/** Deprecated: Use LLVMMDStringInContext2 instead. */
+LLVMValueRef LLVMMDString(const char *Str, unsigned SLen);
+/** Deprecated: Use LLVMMDNodeInContext2 instead. */
+LLVMValueRef LLVMMDNodeInContext(LLVMContextRef C, LLVMValueRef *Vals,
+                                 unsigned Count);
+/** Deprecated: Use LLVMMDNodeInContext2 instead. */
+LLVMValueRef LLVMMDNode(LLVMValueRef *Vals, unsigned Count);
+
 /**
  * @}
  */

llvm/lib/IR/Core.cpp

@@ -1036,6 +1036,16 @@ LLVMValueRef LLVMConstPointerNull(LLVMTypeRef Ty) {
 
 /*--.. Operations on metadata nodes ........................................--*/
 
+LLVMMetadataRef LLVMMDStringInContext2(LLVMContextRef C, const char *Str,
+                                       size_t SLen) {
+  return wrap(MDString::get(*unwrap(C), StringRef(Str, SLen)));
+}
+
+LLVMMetadataRef LLVMMDNodeInContext2(LLVMContextRef C, LLVMMetadataRef *MDs,
+                                     size_t Count) {
+  return wrap(MDNode::get(*unwrap(C), ArrayRef<Metadata*>(unwrap(MDs), Count)));
+}
+
 LLVMValueRef LLVMMDStringInContext(LLVMContextRef C, const char *Str,
                                    unsigned SLen) {
   LLVMContext &Context = *unwrap(C);