Add support for metadata attachments for global variables.

This patch adds an IR, assembly and bitcode representation for metadata
attachments for globals. Future patches will port existing features to use
these new attachments.

Differential Revision: http://reviews.llvm.org/D20074

llvm-svn: 271348

1 files changed, 13 insertions, 2 deletions

diff --git a/llvm/lib/IR/AsmWriter.cpp b/llvm/lib/IR/AsmWriter.cpp
index ec975c77c96..c5002dc8c2f 100644
--- a/llvm/lib/IR/AsmWriter.cpp
+++ b/llvm/lib/IR/AsmWriter.cpp
@@ -681,6 +681,9 @@ private:
   /// Add all of the functions arguments, basic blocks, and instructions.
   void processFunction();
 
+  /// Add the metadata directly attached to a GlobalObject.
+  void processGlobalObjectMetadata(const GlobalObject &GO);
+
   /// Add all of the metadata from a function.
   void processFunctionMetadata(const Function &F);
 
@@ -799,6 +802,7 @@ void SlotTracker::processModule() {
   for (const GlobalVariable &Var : TheModule->globals()) {
     if (!Var.hasName())
       CreateModuleSlot(&Var);
+    processGlobalObjectMetadata(Var);
   }
 
   for (const GlobalAlias &A : TheModule->aliases()) {
@@ -882,12 +886,15 @@ void SlotTracker::processFunction() {
   ST_DEBUG("end processFunction!\n");
 }
 
-void SlotTracker::processFunctionMetadata(const Function &F) {
+void SlotTracker::processGlobalObjectMetadata(const GlobalObject &GO) {
   SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
-  F.getAllMetadata(MDs);
+  GO.getAllMetadata(MDs);
   for (auto &MD : MDs)
     CreateMetadataSlot(MD.second);
+}
 
+void SlotTracker::processFunctionMetadata(const Function &F) {
+  processGlobalObjectMetadata(F);
   for (auto &BB : F) {
     for (auto &I : BB)
       processInstructionMetadata(I);
@@ -2473,6 +2480,10 @@ void AssemblyWriter::printGlobal(const GlobalVariable *GV) {
   if (GV->getAlignment())
     Out << ", align " << GV->getAlignment();
 
+  SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
+  GV->getAllMetadata(MDs);
+  printMetadataAttachments(MDs, ", ");
+
   printInfoComment(*GV);
 }