[llvm-commits] [llvm] r98218 - /llvm/trunk/lib/Target/ARM/AsmPrinter/ARMAsmPrinter.cpp

Bill Wendling isanbard at gmail.com
Wed Mar 10 17:18:13 PST 2010

Author: void
Date: Wed Mar 10 19:18:13 2010
New Revision: 98218

URL: http://llvm.org/viewvc/llvm-project?rev=98218&view=rev
When outputing a non-lazy pointer for a stub, we may need to fill in the value
for the NLP because the object it's pointing to may be internal to the file.

This seems counter-intuitive, but bear with me. When we place the LSDA into the
TEXT section, the type info pointers need to be indirect and pc-rel. We
accomplish this by using NLPs. However, sometimes the types are local to the
file. GCC gets around this by not using a NLP in this case, but a "regular"
indirection like this:

  .long Lfoo-.

__ZTIA:  @ This is local

  .long __ZTIA

LLVM prefers NLPs on Darwin. In fact, it's more optimal for load performance to
use them.


Modified: llvm/trunk/lib/Target/ARM/AsmPrinter/ARMAsmPrinter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/AsmPrinter/ARMAsmPrinter.cpp?rev=98218&r1=98217&r2=98218&view=diff
--- llvm/trunk/lib/Target/ARM/AsmPrinter/ARMAsmPrinter.cpp (original)
+++ llvm/trunk/lib/Target/ARM/AsmPrinter/ARMAsmPrinter.cpp Wed Mar 10 19:18:13 2010
@@ -1137,15 +1137,16 @@
         // L_foo$stub:
         //   .indirect_symbol _foo
-        MCSymbol *MCSym = Stubs[i].second.getPointer();
-        OutStreamer.EmitSymbolAttribute(MCSym, MCSA_IndirectSymbol);
+        MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
+        OutStreamer.EmitSymbolAttribute(MCSym.getPointer(),MCSA_IndirectSymbol);
-        if (MCSym->isUndefined())
+        if (MCSym.getInt())
           // External to current translation unit.
           OutStreamer.EmitIntValue(0, 4/*size*/, 0/*addrspace*/);
           // Internal to current translation unit.
-          OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym, OutContext),
+          OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym.getPointer(),
+                                                        OutContext),
                                 4/*size*/, 0/*addrspace*/);

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