[turbofan] Add CalleeSavedFPRegisters to CallDescriptor.

src/compiler/ppc/linkage-ppc.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/assembler.h"
 #include "src/code-stubs.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/linkage-impl.h"
 #include "src/zone.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 struct PPCLinkageHelperTraits {
   static Register ReturnValueReg() { return r3; }
   static Register ReturnValue2Reg() { return r4; }
   static Register JSCallFunctionReg() { return r4; }
   static Register ContextReg() { return cp; }
   static Register RuntimeCallFunctionReg() { return r4; }
   static Register RuntimeCallArgCountReg() { return r3; }
   static RegList CCalleeSaveRegisters() {
     return r14.bit() | r15.bit() | r16.bit() | r17.bit() | r18.bit() |
            r19.bit() | r20.bit() | r21.bit() | r22.bit() | r23.bit() |
            r24.bit() | r25.bit() | r26.bit() | r27.bit() | r28.bit() |
            r29.bit() | r30.bit() | fp.bit();
   }
+  static RegList CCalleeSaveFPRegisters() {
+    // TODO(palfia): finish.

[paul.l..., 2015/06/23 02:15:02]

Remove the comment for now, and let's just return 0 here, per Matt B.

[akos.palfi.imgtec, 2015/06/23 19:48:57]

Done.

+    return 0;
+  }
   static Register CRegisterParameter(int i) {
     static Register register_parameters[] = {r3, r4, r5, r6, r7, r8, r9, r10};
     return register_parameters[i];
   }
   static int CRegisterParametersLength() { return 8; }
 };
 
 
 typedef LinkageHelper<PPCLinkageHelperTraits> LH;
 
@@ skipping 23 matching lines @@
 
 
 CallDescriptor* Linkage::GetSimplifiedCDescriptor(Zone* zone,
                                                   const MachineSignature* sig) {
   return LH::GetSimplifiedCDescriptor(zone, sig);
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8