Implements far-branches on ARM.

runtime/vm/assembler.cc

 // 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.
 
 #include "vm/assembler.h"
 
 #include "platform/utils.h"
 #include "vm/cpu.h"
 #include "vm/heap.h"
 #include "vm/memory_region.h"
 #include "vm/os.h"
 #include "vm/zone.h"
 
 namespace dart {
 
 DEFINE_FLAG(bool, code_comments, false,
             "Include comments into code and disassembly");
+// TODO(zra): Remove once far branches are enabled automatically on a
+// per-function basis.
+#if defined(TARGET_ARCH_ARM) || defined(TARGET_ARCH_MIPS)
+DEFINE_FLAG(bool, use_far_branches, false, "Enable far branches");
+#endif
 
 
 static uword NewContents(intptr_t capacity) {
   Zone* zone = Isolate::Current()->current_zone();
   uword result = zone->AllocUnsafe(capacity);
 #if defined(DEBUG)
   // Initialize the buffer with kBreakPointInstruction to force a break
   // point if we ever execute an uninitialized part of the code buffer.
   Assembler::InitializeMemoryWithBreakpoints(result, capacity);
 #endif
@@ skipping 182 matching lines @@
 
   for (intptr_t i = 0; i < comments_.length(); i++) {
     comments.SetPCOffsetAt(i, comments_[i]->pc_offset());
     comments.SetCommentAt(i, comments_[i]->comment());
   }
 
   return comments;
 }
 
 }  // namespace dart