Config double register number as 1 for X87 Turbofan.

src/x64/assembler-x64.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 190 matching lines @@
   static const int kMaxNumAllocatableRegisters = 15;
   static int NumAllocatableRegisters() {
     return kMaxNumAllocatableRegisters;
   }
 
   // TODO(turbofan): Proper support for float32.
   static int NumAllocatableAliasedRegisters() {
     return NumAllocatableRegisters();
   }
 
+  static int NumAllocatableRegistersForTurbo() {
+    return kMaxNumAllocatableRegisters;
+  }
+
+  static int NumAllocatableAliasedRegistersForTurbo() {
+    return NumAllocatableAliasedRegisters();
+  }
+
   static int ToAllocationIndex(XMMRegister reg) {
     DCHECK(reg.code() != 0);
     return reg.code() - 1;
   }
 
   static XMMRegister FromAllocationIndex(int index) {
     DCHECK(0 <= index && index < kMaxNumAllocatableRegisters);
     XMMRegister result = { index + 1 };
     return result;
   }
@@ skipping 1935 matching lines @@
  private:
   Assembler* assembler_;
 #ifdef DEBUG
   int space_before_;
 #endif
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_ASSEMBLER_X64_H_