Add support for implicit TLS model used with MS VC runtime.
Patch by Kai Nacke!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150307 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index fd67d62..3a71f4f 100644
--- a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -588,6 +588,11 @@
       COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA |
       COFF::IMAGE_SCN_MEM_READ |
       COFF::IMAGE_SCN_MEM_WRITE;
+  else if (K.isThreadLocal())
+    Flags |=
+      COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
+      COFF::IMAGE_SCN_MEM_READ |
+      COFF::IMAGE_SCN_MEM_WRITE;
   else if (K.isReadOnly())
     Flags |=
       COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
@@ -614,6 +619,8 @@
     return ".text$";
   if (Kind.isBSS ())
     return ".bss$";
+  if (Kind.isThreadLocal())
+    return ".tls$";
   if (Kind.isWriteable())
     return ".data$";
   return ".rdata$";
@@ -623,7 +630,6 @@
 const MCSection *TargetLoweringObjectFileCOFF::
 SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
                        Mangler *Mang, const TargetMachine &TM) const {
-  assert(!Kind.isThreadLocal() && "Doesn't support TLS");
 
   // If this global is linkonce/weak and the target handles this by emitting it
   // into a 'uniqued' section name, create and return the section now.
@@ -644,6 +650,9 @@
   if (Kind.isText())
     return getTextSection();
 
+  if (Kind.isThreadLocal())
+    return getTLSDataSection();
+
   return getDataSection();
 }