Add a DIModule metadata node to the IR.

It is meant to be used to record modules @imported by the current
compile unit, so a debugger an import the same modules to replicate this
environment before dropping into the expression evaluator.

DIModule is a sibling to DINamespace and behaves quite similarly.
In addition to the name of the module it also records the module
configuration details that are necessary to uniquely identify the module.
This includes the configuration macros (e.g., -DNDEBUG), the include path
where the module.map file is to be found, and the isysroot.

The idea is that the backend will turn this into a DW_TAG_module.

http://reviews.llvm.org/D9614
rdar://problem/20965932

llvm-svn: 241017

9 files changed, 126 insertions, 0 deletions

diff --git a/llvm/lib/AsmParser/LLParser.cpp b/llvm/lib/AsmParser/LLParser.cpp
index 0b3f76aa68c..b3c7fa087d4 100644
--- a/llvm/lib/AsmParser/LLParser.cpp
+++ b/llvm/lib/AsmParser/LLParser.cpp
@@ -3676,6 +3676,24 @@ bool LLParser::ParseDINamespace(MDNode *&Result, bool IsDistinct) {
   return false;
 }
 
+/// ParseDIModule:
+///   ::= !DIModule(scope: !0, name: "SomeModule", configMacros: "-DNDEBUG",
+///                 includePath: "/usr/include", isysroot: "/")
+bool LLParser::ParseDIModule(MDNode *&Result, bool IsDistinct) {
+#define VISIT_MD_FIELDS(OPTIONAL, REQUIRED)                                    \
+  REQUIRED(scope, MDField, );                                                  \
+  REQUIRED(name, MDStringField, );                                             \
+  OPTIONAL(configMacros, MDStringField, );                                     \
+  OPTIONAL(includePath, MDStringField, );                                      \
+  OPTIONAL(isysroot, MDStringField, );
+  PARSE_MD_FIELDS();
+#undef VISIT_MD_FIELDS
+
+  Result = GET_OR_DISTINCT(DIModule, (Context, scope.Val, name.Val,
+                           configMacros.Val, includePath.Val, isysroot.Val));
+  return false;
+}
+
 /// ParseDITemplateTypeParameter:
 ///   ::= !DITemplateTypeParameter(name: "Ty", type: !1)
 bool LLParser::ParseDITemplateTypeParameter(MDNode *&Result, bool IsDistinct) {
diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index c47d19356c5..e22420784af 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -1827,6 +1827,20 @@ std::error_code BitcodeReader::parseMetadata() {
           NextMDValueNo++);
       break;
     }
+
+    case bitc::METADATA_MODULE: {
+      if (Record.size() != 6)
+        return error("Invalid record");
+
+      MDValueList.assignValue(
+          GET_OR_DISTINCT(DIModule, Record[0],
+                          (Context, getMDOrNull(Record[1]),
+                          getMDString(Record[2]), getMDString(Record[3]),
+                          getMDString(Record[4]), getMDString(Record[5]))),
+          NextMDValueNo++);
+      break;
+    }
+
     case bitc::METADATA_FILE: {
       if (Record.size() != 3)
         return error("Invalid record");
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index 673d6f1460d..622f7eaf078 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -1032,6 +1032,17 @@ static void WriteDINamespace(const DINamespace *N, const ValueEnumerator &VE,
   Record.clear();
 }
 
+static void WriteDIModule(const DIModule *N, const ValueEnumerator &VE,
+                          BitstreamWriter &Stream,
+                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  for (auto &I : N->operands())
+    Record.push_back(VE.getMetadataOrNullID(I));
+
+  Stream.EmitRecord(bitc::METADATA_MODULE, Record, Abbrev);
+  Record.clear();
+}
+
 static void WriteDITemplateTypeParameter(const DITemplateTypeParameter *N,
                                          const ValueEnumerator &VE,
                                          BitstreamWriter &Stream,
diff --git a/llvm/lib/IR/AsmWriter.cpp b/llvm/lib/IR/AsmWriter.cpp
index 38aa00c9dc7..adc620db897 100644
--- a/llvm/lib/IR/AsmWriter.cpp
+++ b/llvm/lib/IR/AsmWriter.cpp
@@ -1723,6 +1723,20 @@ static void writeDINamespace(raw_ostream &Out, const DINamespace *N,
   Out << ")";
 }
 
+static void writeDIModule(raw_ostream &Out, const DIModule *N,
+                          TypePrinting *TypePrinter, SlotTracker *Machine,
+                          const Module *Context) {
+  Out << "!DIModule(";
+  MDFieldPrinter Printer(Out, TypePrinter, Machine, Context);
+  Printer.printMetadata("scope", N->getRawScope(), /* ShouldSkipNull */ false);
+  Printer.printString("name", N->getName());
+  Printer.printString("configMacros", N->getConfigurationMacros());
+  Printer.printString("includePath", N->getIncludePath());
+  Printer.printString("isysroot", N->getISysRoot());
+  Out << ")";
+}
+
+
 static void writeDITemplateTypeParameter(raw_ostream &Out,
                                          const DITemplateTypeParameter *N,
                                          TypePrinting *TypePrinter,
diff --git a/llvm/lib/IR/DIBuilder.cpp b/llvm/lib/IR/DIBuilder.cpp
index f23f280c978..6a5383d76ef 100644
--- a/llvm/lib/IR/DIBuilder.cpp
+++ b/llvm/lib/IR/DIBuilder.cpp
@@ -186,6 +186,12 @@ DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context,
                                 Context, NS, Line, StringRef(), AllImportedModules);
 }
 
+DIImportedEntity *DIBuilder::createImportedModule(DIScope *Context, DIModule *M,
+                                                  unsigned Line) {
+  return ::createImportedModule(VMContext, dwarf::DW_TAG_imported_module,
+                                Context, M, Line, StringRef(), AllImportedModules);
+}
+
 DIImportedEntity *DIBuilder::createImportedDeclaration(DIScope *Context,
                                                        DINode *Decl,
                                                        unsigned Line,
@@ -703,6 +709,14 @@ DINamespace *DIBuilder::createNameSpace(DIScope *Scope, StringRef Name,
                           LineNo);
 }
 
+DIModule *DIBuilder::createModule(DIScope *Scope, StringRef Name,
+                                  StringRef ConfigurationMacros,
+                                  StringRef IncludePath,
+                                  StringRef ISysRoot) {
+ return DIModule::get(VMContext, getNonCompileUnitScope(Scope), Name,
+                      ConfigurationMacros, IncludePath, ISysRoot);
+}
+
 DILexicalBlockFile *DIBuilder::createLexicalBlockFile(DIScope *Scope,
                                                       DIFile *File,
                                                       unsigned Discriminator) {
diff --git a/llvm/lib/IR/DebugInfo.cpp b/llvm/lib/IR/DebugInfo.cpp
index 2e161c2ba6c..9646d1aa4d7 100644
--- a/llvm/lib/IR/DebugInfo.cpp
+++ b/llvm/lib/IR/DebugInfo.cpp
@@ -145,6 +145,8 @@ void DebugInfoFinder::processModule(const Module &M) {
           processSubprogram(SP);
         else if (auto *NS = dyn_cast<DINamespace>(Entity))
           processScope(NS->getScope());
+        else if (auto *M = dyn_cast<DIModule>(Entity))
+          processScope(M->getScope());
       }
     }
   }
@@ -201,6 +203,8 @@ void DebugInfoFinder::processScope(DIScope *Scope) {
     processScope(LB->getScope());
   } else if (auto *NS = dyn_cast<DINamespace>(Scope)) {
     processScope(NS->getScope());
+  } else if (auto *M = dyn_cast<DIModule>(Scope)) {
+    processScope(M->getScope());
   }
 }
 
diff --git a/llvm/lib/IR/DebugInfoMetadata.cpp b/llvm/lib/IR/DebugInfoMetadata.cpp
index 8b9857d373b..5e017488c1f 100644
--- a/llvm/lib/IR/DebugInfoMetadata.cpp
+++ b/llvm/lib/IR/DebugInfoMetadata.cpp
@@ -138,6 +138,9 @@ DIScopeRef DIScope::getScope() const {
   if (auto *NS = dyn_cast<DINamespace>(this))
     return DIScopeRef(NS->getScope());
 
+  if (auto *M = dyn_cast<DIModule>(this))
+    return DIScopeRef(M->getScope());
+
   assert((isa<DIFile>(this) || isa<DICompileUnit>(this)) &&
          "Unhandled type of scope.");
   return nullptr;
@@ -150,6 +153,8 @@ StringRef DIScope::getName() const {
     return SP->getName();
   if (auto *NS = dyn_cast<DINamespace>(this))
     return NS->getName();
+  if (auto *M = dyn_cast<DIModule>(this))
+    return M->getName();
   assert((isa<DILexicalBlockBase>(this) || isa<DIFile>(this) ||
           isa<DICompileUnit>(this)) &&
          "Unhandled type of scope.");
@@ -410,6 +415,18 @@ DINamespace *DINamespace::getImpl(LLVMContext &Context, Metadata *Scope,
   DEFINE_GETIMPL_STORE(DINamespace, (Line), Ops);
 }
 
+DIModule *DIModule::getImpl(LLVMContext &Context, Metadata *Scope,
+                            MDString *Name, MDString *ConfigurationMacros,
+                            MDString *IncludePath, MDString *ISysRoot,
+                            StorageType Storage, bool ShouldCreate) {
+  assert(isCanonical(Name) && "Expected canonical MDString");
+  DEFINE_GETIMPL_LOOKUP(DIModule,
+    (Scope, getString(Name), getString(ConfigurationMacros),
+     getString(IncludePath), getString(ISysRoot)));
+  Metadata *Ops[] = {Scope, Name, ConfigurationMacros, IncludePath, ISysRoot};
+  DEFINE_GETIMPL_STORE_NO_CONSTRUCTOR_ARGS(DIModule, Ops);
+}
+
 DITemplateTypeParameter *DITemplateTypeParameter::getImpl(LLVMContext &Context,
                                                           MDString *Name,
                                                           Metadata *Type,
diff --git a/llvm/lib/IR/LLVMContextImpl.h b/llvm/lib/IR/LLVMContextImpl.h
index 3a573362b41..cbbf11e334c 100644
--- a/llvm/lib/IR/LLVMContextImpl.h
+++ b/llvm/lib/IR/LLVMContextImpl.h
@@ -651,6 +651,35 @@ template <> struct MDNodeKeyImpl<DINamespace> {
   }
 };
 
+template <> struct MDNodeKeyImpl<DIModule> {
+  Metadata *Scope;
+  StringRef Name;
+  StringRef ConfigurationMacros;
+  StringRef IncludePath;
+  StringRef ISysRoot;
+  MDNodeKeyImpl(Metadata *Scope, StringRef Name,
+                StringRef ConfigurationMacros,
+                StringRef IncludePath,
+                StringRef ISysRoot)
+    : Scope(Scope), Name(Name), ConfigurationMacros(ConfigurationMacros),
+      IncludePath(IncludePath), ISysRoot(ISysRoot) {}
+  MDNodeKeyImpl(const DIModule *N)
+    : Scope(N->getRawScope()), Name(N->getName()),
+      ConfigurationMacros(N->getConfigurationMacros()),
+      IncludePath(N->getIncludePath()), ISysRoot(N->getISysRoot()) {}
+
+  bool isKeyOf(const DIModule *RHS) const {
+    return Scope == RHS->getRawScope() && Name == RHS->getName() &&
+           ConfigurationMacros == RHS->getConfigurationMacros() &&
+           IncludePath == RHS->getIncludePath() &&
+           ISysRoot == RHS->getISysRoot();
+  }
+  unsigned getHashValue() const {
+    return hash_combine(Scope, Name,
+                        ConfigurationMacros, IncludePath, ISysRoot);
+  }
+};
+
 template <> struct MDNodeKeyImpl<DITemplateTypeParameter> {
   StringRef Name;
   Metadata *Type;
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 82cf811910d..3c61165768f 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -1017,6 +1017,11 @@ void Verifier::visitDINamespace(const DINamespace &N) {
     Assert(isa<DIScope>(S), "invalid scope ref", &N, S);
 }
 
+void Verifier::visitDIModule(const DIModule &N) {
+  Assert(N.getTag() == dwarf::DW_TAG_module, "invalid tag", &N);
+  Assert(!N.getName().empty(), "anonymous module", &N);
+}
+
 void Verifier::visitDITemplateParameter(const DITemplateParameter &N) {
   Assert(isTypeRef(N, N.getType()), "invalid type ref", &N, N.getType());
 }