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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185203 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index 6bd4f08..339a5d2 100644
--- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -27,6 +27,7 @@
#include "llvm/Target/Mangler.h"
#include "llvm/Target/TargetFrameLowering.h"
#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetLoweringObjectFile.h"
#include "llvm/Target/TargetRegisterInfo.h"
using namespace llvm;
@@ -1351,7 +1352,23 @@
if (isGlobalVariable) {
addToAccelTable = true;
DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
- addOpAddress(Block, Asm->Mang->getSymbol(GV.getGlobal()));
+ const MCSymbol *Sym = Asm->Mang->getSymbol(GV.getGlobal());
+ if (GV.getGlobal()->isThreadLocal()) {
+ // FIXME: Make this work with -gsplit-dwarf.
+ unsigned PointerSize = Asm->getDataLayout().getPointerSize();
+ assert((PointerSize == 4 || PointerSize == 8) &&
+ "Add support for other sizes if necessary");
+ // Based on GCC's support for TLS:
+ // 1) Start with a constNu of the appropriate pointer size
+ addUInt(Block, 0, dwarf::DW_FORM_data1,
+ PointerSize == 4 ? dwarf::DW_OP_const4u : dwarf::DW_OP_const8u);
+ // 2) containing the (relocated) address of the TLS variable
+ addLabel(Block, 0, dwarf::DW_FORM_udata,
+ Asm->getObjFileLowering().getDebugThreadLocalSymbol(Sym));
+ // 3) followed by a custom OP to tell the debugger about TLS (presumably)
+ addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_lo_user);
+ } else
+ addOpAddress(Block, Sym);
// Do not create specification DIE if context is either compile unit
// or a subprogram.
if (GVContext && GV.isDefinition() && !GVContext.isCompileUnit() &&
@@ -1413,8 +1430,6 @@
if (GV.getLinkageName() != "" && GV.getName() != GV.getLinkageName())
addAccelName(GV.getLinkageName(), AddrDIE);
}
-
- return;
}
/// constructSubrangeDIE - Construct subrange DIE from DISubrange.