Fix problems with sandboxing and the ARM integrated assembler.

src/IceAssembler.cpp

 //===- subzero/src/IceAssembler.cpp - Assembler base class ----------------===//
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
 // Modified by the Subzero authors.
 //
 // This is forked from Dart revision 39313.
 // Please update the revision if we merge back changes from Dart.
 // https://code.google.com/p/dart/wiki/GettingTheSource
@@ skipping 17 matching lines @@
 #include "IceGlobalContext.h"
 #include "IceOperand.h"
 
 namespace Ice {
 
 static uintptr_t NewContents(Assembler &Assemblr, intptr_t Capacity) {
   uintptr_t Result = Assemblr.allocateBytes(Capacity);
   return Result;
 }
 
+void Label::linkTo(const Assembler &Asm, intptr_t Pos) {
+  // We must not set the link until the position is absolutely known. This means
+  // not during the preliminary (sandboxing) pass, and not when the instruction
+  // needs a text fixup (hybrid iasm mode).
+  if (Asm.getPreliminary() || Asm.needsTextFixup())
+    return;
+  assert(!isBound());
+  Position = Pos + kWordSize;
+  assert(isLinked());
+}
+
 void AssemblerBuffer::installFixup(AssemblerFixup *F) {
   if (!Assemblr.getPreliminary())
     Fixups.push_back(F);
 }
 
 AssemblerFixup *AssemblerBuffer::createFixup(FixupKind Kind,
                                              const Constant *Value) {
   AssemblerFixup *F =
       new (Assemblr.allocate<AssemblerFixup>()) AssemblerFixup();
   F->set_kind(Kind);
@@ skipping 100 matching lines @@
   }
   // Handle any bytes that are not prefixed by a fixup.
   for (intptr_t i = CurPosition; i < EndPosition; ++i) {
     Str << "\t.byte 0x";
     Str.write_hex(Buffer.load<uint8_t>(i));
     Str << "\n";
   }
 }
 
 } // end of namespace Ice