[PowerPC] Support TLS variables in debug info

This adds an implementation of getDebugThreadLocalSymbol for
(64-bit) PowerPC.  This needs to return a generic MCExpr
since on ppc64, we need to add a bias of 0x8000 to the
value returned by the R_PPC64_DTPREL64 relocation.

llvm-svn: 185461

2 files changed, 13 insertions, 0 deletions

diff --git a/llvm/lib/Target/PowerPC/PPCTargetObjectFile.cpp b/llvm/lib/Target/PowerPC/PPCTargetObjectFile.cpp
index 90e4f154525..ec1e606eee5 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetObjectFile.cpp
+++ b/llvm/lib/Target/PowerPC/PPCTargetObjectFile.cpp
@@ -55,3 +55,13 @@ SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
 
   return DefaultSection;
 }
+
+const MCExpr *PPC64LinuxTargetObjectFile::
+getDebugThreadLocalSymbol(const MCSymbol *Sym) const {
+  const MCExpr *Expr =
+    MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_PPC_DTPREL, getContext());
+  return MCBinaryExpr::CreateAdd(Expr,
+                                 MCConstantExpr::Create(0x8000, getContext()),
+                                 getContext());
+}
+
diff --git a/llvm/lib/Target/PowerPC/PPCTargetObjectFile.h b/llvm/lib/Target/PowerPC/PPCTargetObjectFile.h
index 9203e235742..262c52213d2 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetObjectFile.h
+++ b/llvm/lib/Target/PowerPC/PPCTargetObjectFile.h
@@ -25,6 +25,9 @@ namespace llvm {
     virtual const MCSection *
     SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
                            Mangler *Mang, const TargetMachine &TM) const;
+
+    /// \brief Describe a TLS variable address within debug info.
+    virtual const MCExpr *getDebugThreadLocalSymbol(const MCSymbol *Sym) const;
   };
 
 }  // end namespace llvm