Abstract out fetching of break_address in debug mode

src/x87/assembler-x87-inl.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // All Rights Reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 // - Redistributions of source code must retain the above copyright notice,
 // this list of conditions and the following disclaimer.
 //
@@ skipping 465 matching lines @@
     CpuFeatures::FlushICache(p, sizeof(int32_t));
   }
 }
 
 
 Address Assembler::target_address_from_return_address(Address pc) {
   return pc - kCallTargetAddressOffset;
 }
 
 
+Address Assembler::break_address_from_return_address(Address pc) {
+  return pc - Assembler::kPatchDebugBreakSlotReturnOffset;
+}
+
+
 Displacement Assembler::disp_at(Label* L) {
   return Displacement(long_at(L->pos()));
 }
 
 
 void Assembler::disp_at_put(Label* L, Displacement disp) {
   long_at_put(L->pos(), disp.data());
 }
 
 
@@ skipping 55 matching lines @@
 
 Operand::Operand(int32_t disp, RelocInfo::Mode rmode) {
   // [disp/r]
   set_modrm(0, ebp);
   set_dispr(disp, rmode);
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_X87_ASSEMBLER_X87_INL_H_