Extend the IL for selecting TLS models (PR9788)

This allows the user/front-end to specify a model that is better
than what LLVM would choose by default. For example, a variable
might be declared as

  @x = thread_local(initialexec) global i32 42

if it will not be used in a shared library that is dlopen'ed.

If the specified model isn't supported by the target, or if LLVM can
make a better choice, a different model may be used.

llvm-svn: 159077

1 files changed, 24 insertions, 1 deletions

diff --git a/llvm/lib/Target/CppBackend/CPPBackend.cpp b/llvm/lib/Target/CppBackend/CPPBackend.cpp
index cd2ebcb5087..0ea2a299dd8 100644
--- a/llvm/lib/Target/CppBackend/CPPBackend.cpp
+++ b/llvm/lib/Target/CppBackend/CPPBackend.cpp
@@ -130,6 +130,7 @@ namespace {
   private:
     void printLinkageType(GlobalValue::LinkageTypes LT);
     void printVisibilityType(GlobalValue::VisibilityTypes VisTypes);
+    void printThreadLocalMode(GlobalVariable::ThreadLocalMode TLM);
     void printCallingConv(CallingConv::ID cc);
     void printEscapedString(const std::string& str);
     void printCFP(const ConstantFP* CFP);
@@ -325,6 +326,26 @@ void CppWriter::printVisibilityType(GlobalValue::VisibilityTypes VisType) {
   }
 }
 
+void CppWriter::printThreadLocalMode(GlobalVariable::ThreadLocalMode TLM) {
+  switch (TLM) {
+    case GlobalVariable::NotThreadLocal:
+      Out << "GlobalVariable::NotThreadLocal";
+      break;
+    case GlobalVariable::GeneralDynamicTLSModel:
+      Out << "GlobalVariable::GeneralDynamicTLSModel";
+      break;
+    case GlobalVariable::LocalDynamicTLSModel:
+      Out << "GlobalVariable::LocalDynamicTLSModel";
+      break;
+    case GlobalVariable::InitialExecTLSModel:
+      Out << "GlobalVariable::InitialExecTLSModel";
+      break;
+    case GlobalVariable::LocalExecTLSModel:
+      Out << "GlobalVariable::LocalExecTLSModel";
+      break;
+  }
+}
+
 // printEscapedString - Print each character of the specified string, escaping
 // it if it is not printable or if it is an escape char.
 void CppWriter::printEscapedString(const std::string &Str) {
@@ -996,7 +1017,9 @@ void CppWriter::printVariableHead(const GlobalVariable *GV) {
   }
   if (GV->isThreadLocal()) {
     printCppName(GV);
-    Out << "->setThreadLocal(true);";
+    Out << "->setThreadLocalMode(";
+    printThreadLocalMode(GV->getThreadLocalMode());
+    Out << ");";
     nl(Out);
   }
   if (is_inline) {