Add support for metadata representing .ident directives.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192764 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 60f1bff..0fe341a 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -953,6 +953,9 @@
     if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
       MP->finishAssembly(*this);
 
+  // Emit llvm.ident metadata in an '.ident' directive.
+  EmitModuleIdents(M);
+
   // If we don't have any trampolines, then we don't require stack memory
   // to be executable. Some targets have a directive to declare this.
   Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
@@ -1332,6 +1335,21 @@
   }
 }
 
+void AsmPrinter::EmitModuleIdents(Module &M) {
+  if (!MAI->hasIdentDirective())
+    return;
+
+  if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
+    for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
+      const MDNode *N = NMD->getOperand(i);
+      assert(N->getNumOperands() == 1 && 
+             "llvm.ident metadata entry can have only one operand");
+      const MDString *S = cast<MDString>(N->getOperand(0));
+      OutStreamer.EmitIdent(S->getString());
+    }
+  }
+}
+
 //===--------------------------------------------------------------------===//
 // Emission and print routines
 //
diff --git a/lib/IR/Verifier.cpp b/lib/IR/Verifier.cpp
index c7559c1..7d657de 100644
--- a/lib/IR/Verifier.cpp
+++ b/lib/IR/Verifier.cpp
@@ -216,6 +216,7 @@
         visitNamedMDNode(*I);
 
       visitModuleFlags(M);
+      visitModuleIdents(M);
 
       // Verify Debug Info.
       verifyDebugInfo(M);
@@ -260,6 +261,7 @@
     void visitGlobalAlias(GlobalAlias &GA);
     void visitNamedMDNode(NamedMDNode &NMD);
     void visitMDNode(MDNode &MD, Function *F);
+    void visitModuleIdents(Module &M);
     void visitModuleFlags(Module &M);
     void visitModuleFlag(MDNode *Op, DenseMap<MDString*, MDNode*> &SeenIDs,
                          SmallVectorImpl<MDNode*> &Requirements);
@@ -613,6 +615,24 @@
   }
 }
 
+void Verifier::visitModuleIdents(Module &M) {
+  const NamedMDNode *Idents = M.getNamedMetadata("llvm.ident");
+  if (!Idents) 
+    return;
+  
+  // llvm.ident takes a list of metadata entry. Each entry has only one string.
+  // Scan each llvm.ident entry and make sure that this requirement is met.
+  for (unsigned i = 0, e = Idents->getNumOperands(); i != e; ++i) {
+    const MDNode *N = Idents->getOperand(i);
+    Assert1(N->getNumOperands() == 1,
+            "incorrect number of operands in llvm.ident metadata", N);
+    Assert1(isa<MDString>(N->getOperand(0)),
+            ("invalid value for llvm.ident metadata entry operand"
+             "(the operand should be a string)"),
+            N->getOperand(0));
+  } 
+}
+
 void Verifier::visitModuleFlags(Module &M) {
   const NamedMDNode *Flags = M.getModuleFlagsMetadata();
   if (!Flags) return;