PPC: [turbofan] Add basic support for calling to (a subset of) C functions.

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"
 
@@ skipping 12 matching lines @@
     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 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; }
+  static int CStackBackingStoreLength() { return 0; }
 };
 
 
 typedef LinkageHelper<PPCLinkageHelperTraits> LH;
 
 CallDescriptor* Linkage::GetJSCallDescriptor(Zone* zone, bool is_osr,
                                              int parameter_count,
                                              CallDescriptor::Flags flags) {
   return LH::GetJSCallDescriptor(zone, is_osr, parameter_count, flags);
 }
@@ skipping 18 matching lines @@
 
 
 CallDescriptor* Linkage::GetSimplifiedCDescriptor(Zone* zone,
                                                   const MachineSignature* sig) {
   return LH::GetSimplifiedCDescriptor(zone, sig);
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8