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

lib/MC/MCAsmStreamer.cpp

 //===- lib/MC/MCAsmStreamer.cpp - Text Assembly Output --------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include "llvm/MC/MCStreamer.h"
@@ skipping 36 matching lines @@
 
   SmallString<128> CommentToEmit;
   raw_svector_ostream CommentStream;
 
   unsigned IsVerboseAsm : 1;
   unsigned ShowInst : 1;
   unsigned UseDwarfDirectory : 1;
   // @LOCALMOD: we don't have an MCAssembler object here, so we can't ask it
   // if bundle alignment is enabled. Instead, just track the alignment here.
   unsigned BundleAlignmentEnabled : 1;
+  unsigned BundleLocked : 1;
 
   void EmitRegisterName(int64_t Register);
   void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) override;
   void EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) override;
 
 public:
   MCAsmStreamer(MCContext &Context, std::unique_ptr<formatted_raw_ostream> os,
                 bool isVerboseAsm, bool useDwarfDirectory,
                 MCInstPrinter *printer, MCCodeEmitter *emitter,
                 MCAsmBackend *asmbackend, bool showInst)
@@ skipping 1182 matching lines @@
     OS << "  fixup " << char('A' + i) << " - " << "offset: " << F.getOffset()
        << ", value: " << *F.getValue() << ", kind: " << Info.Name << "\n";
   }
 }
 
 void MCAsmStreamer::EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) {
   assert(getCurrentSection().first &&
          "Cannot emit contents before setting section!");
 
   // @LOCALMOD-START
-  if (NaClExpander && NaClExpander->expandInst(Inst, *this, STI))
+  if (NaClExpander && !BundleLocked &&
+      NaClExpander->expandInst(Inst, *this, STI))
     return;
 
   if (BundleAlignmentEnabled && AsmBackend &&
       AsmBackend->CustomExpandInst(Inst, *this)) {
     return;
   }
   // @LOCALMOD-END
   // Show the encoding in a comment if we have a code emitter.
   if (Emitter)
     AddEncodingComment(Inst, STI);
@@ skipping 15 matching lines @@
 void MCAsmStreamer::EmitBundleAlignMode(unsigned AlignPow2) {
   OS << "\t.bundle_align_mode " << AlignPow2;
   BundleAlignmentEnabled = AlignPow2 > 0; // @LOCALMOD
   EmitEOL();
 }
 
 void MCAsmStreamer::EmitBundleLock(bool AlignToEnd) {
   OS << "\t.bundle_lock";
   if (AlignToEnd)
     OS << " align_to_end";
+  BundleLocked = true; // @LOCALMOD
   EmitEOL();
 }
 
 void MCAsmStreamer::EmitBundleUnlock() {
   OS << "\t.bundle_unlock";
+  BundleLocked = false; // @LOCALMOD
   EmitEOL();
 }
 
 /// EmitRawText - If this file is backed by an assembly streamer, this dumps
 /// the specified string in the output .s file.  This capability is
 /// indicated by the hasRawTextSupport() predicate.
 void MCAsmStreamer::EmitRawTextImpl(StringRef String) {
   if (!String.empty() && String.back() == '\n')
     String = String.substr(0, String.size()-1);
   OS << String;
@@ skipping 19 matching lines @@
 }
 
 MCStreamer *llvm::createAsmStreamer(MCContext &Context,
                                     std::unique_ptr<formatted_raw_ostream> OS,
                                     bool isVerboseAsm, bool useDwarfDirectory,
                                     MCInstPrinter *IP, MCCodeEmitter *CE,
                                     MCAsmBackend *MAB, bool ShowInst) {
   return new MCAsmStreamer(Context, std::move(OS), isVerboseAsm,
                            useDwarfDirectory, IP, CE, MAB, ShowInst);
 }