6 files changed, 42 insertions, 11 deletions
diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp
index 1d763d66dd..718cd12389 100644
--- a/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -530,9 +530,9 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
   if (!M->getTargetTriple().empty())
     WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(),
                       0/*TODO*/, Stream);
-  if (!M->getDataLayout().empty())
-    WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, M->getDataLayout(),
-                      0/*TODO*/, Stream);
+  const std::string &DL = M->getDataLayoutStr();
+  if (!DL.empty())
+    WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, DL, 0 /*TODO*/, Stream);
   if (!M->getModuleInlineAsm().empty())
     WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(),
                       0/*TODO*/, Stream);
diff --git a/lib/IR/AsmWriter.cpp b/lib/IR/AsmWriter.cpp
index c48214cc2f..d414f764d3 100644
--- a/lib/IR/AsmWriter.cpp
+++ b/lib/IR/AsmWriter.cpp
@@ -1252,8 +1252,9 @@ void AssemblyWriter::printModule(const Module *M) {
       M->getModuleIdentifier().find('\n') == std::string::npos)
     Out << "; ModuleID = '" << M->getModuleIdentifier() << "'\n";
 
-  if (!M->getDataLayout().empty())
-    Out << "target datalayout = \"" << M->getDataLayout() << "\"\n";
+  const std::string &DL = M->getDataLayoutStr();
+  if (!DL.empty())
+    Out << "target datalayout = \"" << DL << "\"\n";
   if (!M->getTargetTriple().empty())
     Out << "target triple = \"" << M->getTargetTriple() << "\"\n";
 
diff --git a/lib/IR/Core.cpp b/lib/IR/Core.cpp
index 68bc5c5810..b19fbe3fda 100644
--- a/lib/IR/Core.cpp
+++ b/lib/IR/Core.cpp
@@ -107,7 +107,7 @@ void LLVMDisposeModule(LLVMModuleRef M) {
 
 /*--.. Data layout .........................................................--*/
 const char * LLVMGetDataLayout(LLVMModuleRef M) {
-  return unwrap(M)->getDataLayout().c_str();
+  return unwrap(M)->getDataLayoutStr().c_str();
 }
 
 void LLVMSetDataLayout(LLVMModuleRef M, const char *Triple) {
diff --git a/lib/IR/DataLayout.cpp b/lib/IR/DataLayout.cpp
index 44410ceb68..d60c79f52e 100644
--- a/lib/IR/DataLayout.cpp
+++ b/lib/IR/DataLayout.cpp
@@ -344,7 +344,13 @@ void DataLayout::parseSpecifier(StringRef Desc) {
   }
 }
 
-DataLayout::DataLayout(const Module *M) { init(M->getDataLayout()); }
+DataLayout::DataLayout(const Module *M) {
+  const DataLayout *Other = M->getDataLayout();
+  if (Other)
+    *this = *Other;
+  else
+    init("");
+}
 
 void
 DataLayout::setAlignment(AlignTypeEnum align_type, unsigned abi_align,
diff --git a/lib/IR/Module.cpp b/lib/IR/Module.cpp
index d911c7e2b5..739f8888f9 100644
--- a/lib/IR/Module.cpp
+++ b/lib/IR/Module.cpp
@@ -42,8 +42,8 @@ template class llvm::SymbolTableListTraits<GlobalAlias, Module>;
 // Primitive Module methods.
 //
 
-Module::Module(StringRef MID, LLVMContext& C)
-  : Context(C), Materializer(NULL), ModuleID(MID) {
+Module::Module(StringRef MID, LLVMContext &C)
+    : Context(C), Materializer(NULL), ModuleID(MID), DL("") {
   ValSymTab = new ValueSymbolTable();
   NamedMDSymTab = new StringMap<NamedMDNode *>();
   Context.addModule(this);
@@ -338,6 +338,30 @@ void Module::addModuleFlag(MDNode *Node) {
   getOrInsertModuleFlagsMetadata()->addOperand(Node);
 }
 
+void Module::setDataLayout(StringRef Desc) {
+  if (Desc.empty()) {
+    DataLayoutStr = "";
+  } else {
+    DL.init(Desc);
+    DataLayoutStr = DL.getStringRepresentation();
+  }
+}
+
+void Module::setDataLayout(const DataLayout *Other) {
+  if (!Other) {
+    DataLayoutStr = "";
+  } else {
+    DL = *Other;
+    DataLayoutStr = DL.getStringRepresentation();
+  }
+}
+
+const DataLayout *Module::getDataLayout() const {
+  if (DataLayoutStr.empty())
+    return 0;
+  return &DL;
+}
+
 //===----------------------------------------------------------------------===//
 // Methods to control the materialization of GlobalValues in the Module.
 //
diff --git a/lib/Linker/LinkModules.cpp b/lib/Linker/LinkModules.cpp
index 1bfc8284b8..f1b8cb7610 100644
--- a/lib/Linker/LinkModules.cpp
+++ b/lib/Linker/LinkModules.cpp
@@ -1200,14 +1200,14 @@ bool ModuleLinker::run() {
 
   // Inherit the target data from the source module if the destination module
   // doesn't have one already.
-  if (DstM->getDataLayout().empty() && !SrcM->getDataLayout().empty())
+  if (!DstM->getDataLayout() && SrcM->getDataLayout())
     DstM->setDataLayout(SrcM->getDataLayout());
 
   // Copy the target triple from the source to dest if the dest's is empty.
   if (DstM->getTargetTriple().empty() && !SrcM->getTargetTriple().empty())
     DstM->setTargetTriple(SrcM->getTargetTriple());
 
-  if (!SrcM->getDataLayout().empty() && !DstM->getDataLayout().empty() &&
+  if (SrcM->getDataLayout() && DstM->getDataLayout() &&
       SrcM->getDataLayout() != DstM->getDataLayout()) {
     if (!SuppressWarnings) {
       errs() << "WARNING: Linking two modules of different data layouts!\n";