Introducing LLVMMetadataRef

Summary:
This seems like an uncontroversial first step toward providing access to the metadata hierarchy that now exists in LLVM. This should allow for good debug info support from C.

Future plans are to deprecate API that take mixed bags of values and metadata (mainly the LLVMMDNode family of functions) and migrate the rest toward the use of LLVMMetadataRef.

Once this is in place, mapping of DIBuilder will be able to start.

Reviewers: mehdi_amini, echristo, whitequark, jketema, Wallbraker

Reviewed By: Wallbraker

Subscribers: Eugene.Zelenko, axw, mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D19448

llvm-svn: 300447

diff --git a/llvm/bindings/go/llvm/IRBindings.h b/llvm/bindings/go/llvm/IRBindings.h
index f4f4903..25a00b1 100644 (file)
--- a/llvm/bindings/go/llvm/IRBindings.h
+++ b/llvm/bindings/go/llvm/IRBindings.h
@@ -26,7 +26,6 @@
 extern "C" {
 #endif
 
-typedef struct LLVMOpaqueMetadata *LLVMMetadataRef;
 struct LLVMDebugLocMetadata{
     unsigned Line;
     unsigned Col;
@@ -59,16 +58,6 @@ void LLVMSetSubprogram(LLVMValueRef Fn, LLVMMetadataRef SP);
 #ifdef __cplusplus
 }
 
-namespace llvm {
-
-DEFINE_ISA_CONVERSION_FUNCTIONS(Metadata, LLVMMetadataRef)
-
-inline Metadata **unwrap(LLVMMetadataRef *Vals) {
-  return reinterpret_cast<Metadata**>(Vals);
-}
-
-}
-
 #endif
 
 #endif

diff --git a/llvm/include/llvm-c/Core.h b/llvm/include/llvm-c/Core.h
index 7f5c05d..0a1d8fa 100644 (file)
--- a/llvm/include/llvm-c/Core.h
+++ b/llvm/include/llvm-c/Core.h
@@ -2131,6 +2131,16 @@ LLVMValueRef LLVMMDNodeInContext(LLVMContextRef C, LLVMValueRef *Vals,
 LLVMValueRef LLVMMDNode(LLVMValueRef *Vals, unsigned Count);
 
 /**
+ * Obtain a Metadata as a Value.
+ */
+LLVMValueRef LLVMMetadataAsValue(LLVMContextRef C, LLVMMetadataRef MD);
+
+/**
+ * Obtain a Value as a Metadata.
+ */
+LLVMMetadataRef LLVMValueAsMetadata(LLVMValueRef Val);
+
+/**
  * Obtain the underlying string from a MDString value.
  *
  * @param V Instance to obtain string from.

diff --git a/llvm/include/llvm-c/Types.h b/llvm/include/llvm-c/Types.h
index 3d472a6..13fb36e 100644 (file)
--- a/llvm/include/llvm-c/Types.h
+++ b/llvm/include/llvm-c/Types.h
@@ -83,6 +83,13 @@ typedef struct LLVMOpaqueValue *LLVMValueRef;
 typedef struct LLVMOpaqueBasicBlock *LLVMBasicBlockRef;
 
 /**
+ * Represents an LLVM Metadata.
+ *
+ * This models llvm::Metadata.
+ */
+typedef struct LLVMOpaqueMetadata *LLVMMetadataRef;
+
+/**
  * Represents an LLVM basic block builder.
  *
  * This models llvm::IRBuilder.

diff --git a/llvm/include/llvm/IR/Metadata.h b/llvm/include/llvm/IR/Metadata.h
index fd79355..8f24a6a 100644 (file)
--- a/llvm/include/llvm/IR/Metadata.h
+++ b/llvm/include/llvm/IR/Metadata.h
@@ -30,6 +30,7 @@
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Value.h"
 #include "llvm/Support/Casting.h"
+#include "llvm/Support/CBindingWrapping.h"
 #include "llvm/Support/ErrorHandling.h"
 #include <cassert>
 #include <cstddef>
@@ -133,6 +134,14 @@ public:
   /// @}
 };
 
+// Create wrappers for C Binding types (see CBindingWrapping.h).
+DEFINE_ISA_CONVERSION_FUNCTIONS(Metadata, LLVMMetadataRef)
+
+// Specialized opaque metadata conversions.
+inline Metadata **unwrap(LLVMMetadataRef *MDs) {
+  return reinterpret_cast<Metadata**>(MDs);
+}
+
 #define HANDLE_METADATA(CLASS) class CLASS;
 #include "llvm/IR/Metadata.def"
 

diff --git a/llvm/lib/IR/Core.cpp b/llvm/lib/IR/Core.cpp
index b5ed30b..bc7cf0b 100644 (file)
--- a/llvm/lib/IR/Core.cpp
+++ b/llvm/lib/IR/Core.cpp
@@ -863,6 +863,19 @@ LLVMValueRef LLVMMDNode(LLVMValueRef *Vals, unsigned Count) {
   return LLVMMDNodeInContext(LLVMGetGlobalContext(), Vals, Count);
 }
 
+LLVMValueRef LLVMMetadataAsValue(LLVMContextRef C, LLVMMetadataRef MD) {
+  return wrap(MetadataAsValue::get(*unwrap(C), unwrap(MD)));
+}
+
+LLVMMetadataRef LLVMValueAsMetadata(LLVMValueRef Val) {
+  auto *V = unwrap(Val);
+  if (auto *C = dyn_cast<Constant>(V))
+    return wrap(ConstantAsMetadata::get(C));
+  if (auto *MAV = dyn_cast<MetadataAsValue>(V))
+    return wrap(MAV->getMetadata());
+  return wrap(ValueAsMetadata::get(V));
+}
+
 const char *LLVMGetMDString(LLVMValueRef V, unsigned *Length) {
   if (const auto *MD = dyn_cast<MetadataAsValue>(unwrap(V)))
     if (const MDString *S = dyn_cast<MDString>(MD->getMetadata())) {