Check for metadata in PNaCl ABI checker.

lib/Analysis/NaCl/PNaClABIVerifyModule.cpp

Index: lib/Analysis/NaCl/PNaClABIVerifyModule.cpp
diff --git a/lib/Analysis/NaCl/PNaClABIVerifyModule.cpp b/lib/Analysis/NaCl/PNaClABIVerifyModule.cpp
index 88914c85a8a336b85630a35d754c213ac2ba9c05..5055a58223a8ae8e9350dca4e19f8b9c28a78ff7 100644
--- a/lib/Analysis/NaCl/PNaClABIVerifyModule.cpp
+++ b/lib/Analysis/NaCl/PNaClABIVerifyModule.cpp
@@ -31,13 +31,16 @@ class PNaClABIVerifyModule : public ModulePass {
   PNaClABIVerifyModule() :
       ModulePass(ID),
       Reporter(new PNaClABIErrorReporter),
-      ReporterIsOwned(true) {
+      ReporterIsOwned(true),
+      AllowDebugMetadata(false) {
     initializePNaClABIVerifyModulePass(*PassRegistry::getPassRegistry());
   }
-  explicit PNaClABIVerifyModule(PNaClABIErrorReporter *Reporter_) :
+  PNaClABIVerifyModule(PNaClABIErrorReporter *Reporter_,
+                       bool AllowDebugMetadata_) :
       ModulePass(ID),
       Reporter(Reporter_),
-      ReporterIsOwned(false) {
+      ReporterIsOwned(false),
+      AllowDebugMetadata(AllowDebugMetadata_) {
     initializePNaClABIVerifyModulePass(*PassRegistry::getPassRegistry());
   }
   ~PNaClABIVerifyModule() {
@@ -48,9 +51,11 @@ class PNaClABIVerifyModule : public ModulePass {
   virtual void print(raw_ostream &O, const Module *M) const;
  private:
   void CheckGlobalValueCommon(const GlobalValue *GV);
+  bool WhiteListedMetadata(const NamedMDNode *MD);
   PNaClABITypeChecker TC;
   PNaClABIErrorReporter *Reporter;
   bool ReporterIsOwned;
+  bool AllowDebugMetadata;
 };
 
 static const char *linkageName(GlobalValue::LinkageTypes LT) {
@@ -105,6 +110,10 @@ void PNaClABIVerifyModule::CheckGlobalValueCommon(const GlobalValue *GV) {
   }
 }
 
+bool PNaClABIVerifyModule::WhiteListedMetadata(const NamedMDNode* MD) {
+  return MD->getName().startswith("llvm.dbg") && AllowDebugMetadata;
+}
+
 bool PNaClABIVerifyModule::runOnModule(Module &M) {
   for (Module::const_global_iterator MI = M.global_begin(), ME = M.global_end();
        MI != ME; ++MI) {
@@ -174,11 +183,17 @@ bool PNaClABIVerifyModule::runOnModule(Module &M) {
   // Check named metadata nodes
   for (Module::const_named_metadata_iterator I = M.named_metadata_begin(),
            E = M.named_metadata_end(); I != E; ++I) {
-    for (unsigned i = 0, e = I->getNumOperands(); i != e; i++) {
-      if (Type *T = TC.checkTypesInMDNode(I->getOperand(i))) {
-        Reporter->addError() << "Named metadata node " << I->getName() <<
-            " refers to disallowed type: " <<
-            PNaClABITypeChecker::getTypeName(T) << "\n";
+    if (!WhiteListedMetadata(I)) {
+      Reporter->addError() << "Named metadata node " << I->getName()
+                           << " is disallowed\n";
+    } else {
+      // Check the types in the metadata.
+      for (unsigned i = 0, e = I->getNumOperands(); i != e; i++) {
+        if (Type *T = TC.checkTypesInMDNode(I->getOperand(i))) {
+          Reporter->addError() << "Named metadata node " << I->getName()
+                               << " refers to disallowed type: "
+                               << PNaClABITypeChecker::getTypeName(T) << "\n";
+        }
       }
     }
   }
@@ -201,6 +216,7 @@ INITIALIZE_PASS(PNaClABIVerifyModule, "verify-pnaclabi-module",
                 "Verify module for PNaCl", false, true)
 
 ModulePass *llvm::createPNaClABIVerifyModulePass(
-    PNaClABIErrorReporter *Reporter) {
-  return new PNaClABIVerifyModule(Reporter);
+    PNaClABIErrorReporter *Reporter,
+    bool AllowDebugMetadata) {
+  return new PNaClABIVerifyModule(Reporter, AllowDebugMetadata);
 }