DebugInfo: PR14728: TLS support

Based on GCC's output for TLS variables (OP_constNu, x@dtpoff,
OP_lo_user), this implements debug info support for TLS in ELF. Verified
that this output is correct/sufficient on Linux (using gold - if you're
using binutils-ld, you'll need something with the fix for
http://sourceware.org/bugzilla/show_bug.cgi?id=15685 in it).

Support on non-ELF is sort of "arbitrary" at the moment - if Apple folks
want to discuss (or just go ahead & implement) how this should work in
MachO, etc, I'm open.

llvm-svn: 185203

1 files changed, 6 insertions, 0 deletions

diff --git a/llvm/lib/Target/TargetLoweringObjectFile.cpp b/llvm/lib/Target/TargetLoweringObjectFile.cpp
index f5121e34f77..fc50aa5192a 100644
--- a/llvm/lib/Target/TargetLoweringObjectFile.cpp
+++ b/llvm/lib/Target/TargetLoweringObjectFile.cpp
@@ -317,3 +317,9 @@ getTTypeReference(const MCSymbolRefExpr *Sym, unsigned Encoding,
   }
   }
 }
+
+const MCSymbolRefExpr *TargetLoweringObjectFile::getDebugThreadLocalSymbol(const MCSymbol *Sym) const {
+  // FIXME: It's not clear what, if any, default this should have - perhaps a
+  // null return could mean 'no location' & we should just do that here.
+  return MCSymbolRefExpr::Create(Sym, *Ctx);
+}