Auto-sandboxing: Don't expand instructions when in a bundle-locked group

lib/MC/MCObjectStreamer.cpp

 //===- lib/MC/MCObjectStreamer.cpp - Object File MCStreamer Interface -----===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include "llvm/MC/MCObjectStreamer.h"
@@ skipping 195 matching lines @@
 
 void MCObjectStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
   getAssembler().getOrCreateSymbolData(*Symbol);
   MCStreamer::EmitAssignment(Symbol, Value);
 }
 
 void MCObjectStreamer::EmitInstruction(const MCInst &Inst,
                                        const MCSubtargetInfo &STI) {
 
   // @LOCALMOD-START
-  if (NaClExpander && NaClExpander->expandInst(Inst, *this, STI))
+  MCSectionData *SD = getCurrentSectionData();
+  if (!SD->isBundleLocked() && NaClExpander && NaClExpander->expandInst(Inst, *this, STI))
     return;
 
   if (getAssembler().isBundlingEnabled() &&
       getAssembler().getBackend().CustomExpandInst(Inst, *this)) {
     return;
   }
   // @LOCALMOD-END
 
   MCStreamer::EmitInstruction(Inst, STI);
 
-  MCSectionData *SD = getCurrentSectionData();
+
   SD->setHasInstructions(true);
 
   // Now that a machine instruction has been assembled into this section, make
   // a line entry for any .loc directive that has been seen.
   MCLineEntry::Make(this, getCurrentSection().first);
 
   // If this instruction doesn't need relaxation, just emit it as data.
   MCAssembler &Assembler = getAssembler();
   if (!Assembler.getBackend().mayNeedRelaxation(Inst)) {
     EmitInstToData(Inst, STI);
@@ skipping 205 matching lines @@
   // If we are generating dwarf for assembly source files dump out the sections.
   if (getContext().getGenDwarfForAssembly())
     MCGenDwarfInfo::Emit(this);
 
   // Dump out the dwarf file & directory tables and line tables.
   MCDwarfLineTable::Emit(this);
 
   flushPendingLabels(nullptr);
   getAssembler().Finish();
 }