Enables per-function far-branches for ARM and MIPS.

runtime/vm/assembler_mips.h

 // Copyright (c) 2013, 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.
 
 #ifndef VM_ASSEMBLER_MIPS_H_
 #define VM_ASSEMBLER_MIPS_H_
 
 #ifndef VM_ASSEMBLER_H_
 #error Do not include assembler_mips.h directly; use assembler.h instead.
 #endif
@@ skipping 127 matching lines @@
  public:
   static void InitOnce() { }
   static bool double_truncate_round_supported() {
     return false;
   }
 };
 
 
 class Assembler : public ValueObject {
  public:
-  Assembler()
+  explicit Assembler(bool use_far_branches = false)
       : buffer_(),
         object_pool_(GrowableObjectArray::Handle()),
         prologue_offset_(-1),
+        use_far_branches_(use_far_branches),
         delay_slot_available_(false),
         in_delay_slot_(false),
         comments_() { }
   ~Assembler() { }
 
   void PopRegister(Register r) { Pop(r); }
 
   void Bind(Label* label);
 
   // Misc. functionality
   int CodeSize() const { return buffer_.Size(); }
   int prologue_offset() const { return prologue_offset_; }
   const ZoneGrowableArray<int>& GetPointerOffsets() const {
     return buffer_.pointer_offsets();
   }
   const GrowableObjectArray& object_pool() const { return object_pool_; }
   void FinalizeInstructions(const MemoryRegion& region) {
     buffer_.FinalizeInstructions(region);
   }
 
+  bool use_far_branches() const {
+    return FLAG_use_far_branches || use_far_branches_;
+  }
+
   // Set up a stub frame so that the stack traversal code can easily identify
   // a stub frame.
   void EnterStubFrame(bool uses_pp = false);
   void LeaveStubFrame(bool uses_pp = false);
   // A separate macro for when a Ret immediately follows, so that we can use
   // the branch delay slot.
   void LeaveStubFrameAndReturn(Register ra = RA, bool uses_pp = false);
 
   // Instruction pattern from entrypoint is used in dart frame prologs
   // to set up the frame and save a PC which can be used to figure out the
@@ skipping 905 matching lines @@
   // Set up a Dart frame for a function compiled for on-stack replacement.
   // The frame layout is a normal Dart frame, but the frame is partially set
   // up on entry (it is the frame of the unoptimized code).
   void EnterOsrFrame(intptr_t extra_size);
 
  private:
   AssemblerBuffer buffer_;
   GrowableObjectArray& object_pool_;  // Objects and patchable jump targets.
   int prologue_offset_;
 
+  const bool use_far_branches_;
   bool delay_slot_available_;
   bool in_delay_slot_;
 
   int32_t AddObject(const Object& obj);
   int32_t AddExternalLabel(const ExternalLabel* label);
 
   class CodeComment : public ZoneAllocated {
    public:
     CodeComment(intptr_t pc_offset, const String& comment)
         : pc_offset_(pc_offset), comment_(comment) { }
@@ skipping 80 matching lines @@
                     FRegister fd,
                     Cop1Function func) {
     Emit(opcode << kOpcodeShift |
          fmt << kFmtShift |
          ft << kFtShift |
          fs << kFsShift |
          fd << kFdShift |
          func << kCop1FnShift);
   }
 
+  int32_t EncodeBranchOffset(int32_t offset, int32_t instr);
 
   void EmitFarJump(int32_t offset, bool link);
   void EmitFarBranch(Opcode b, Register rs, Register rt, int32_t offset);
   void EmitFarRegImmBranch(RtRegImm b, Register rs, int32_t offset);
   void EmitFarFpuBranch(bool kind, int32_t offset);
   void EmitBranch(Opcode b, Register rs, Register rt, Label* label);
   void EmitRegImmBranch(RtRegImm b, Register rs, Label* label);
   void EmitFpuBranch(bool kind, Label *label);
 
   void EmitBranchDelayNop() {
     Emit(Instr::kNopInstruction);  // Branch delay NOP.
     delay_slot_available_ = true;
   }
 
   void StoreIntoObjectFilter(Register object, Register value, Label* no_update);
 
   // Shorter filtering sequence that assumes that value is not a smi.
   void StoreIntoObjectFilterNoSmi(Register object,
                                   Register value,
                                   Label* no_update);
 
   DISALLOW_ALLOCATION();
   DISALLOW_COPY_AND_ASSIGN(Assembler);
 };
 
 }  // namespace dart
 
 #endif  // VM_ASSEMBLER_MIPS_H_