text: /*
   * Copyright (C) 2016-2017 Apple 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:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
   * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
   */
  
  #include "config.h"
  #include "AirCCallingConvention.h"
  
  #if ENABLE(B3_JIT)
  
  #include "AirCCallSpecial.h"
  #include "AirCode.h"
  #include "B3CCallValue.h"
  
  namespace JSC { namespace B3 { namespace Air {
  
  namespace {
  
  template<typename BankInfo>
  Arg marshallCCallArgumentImpl(unsigned& argumentCount, unsigned& stackOffset, Value* child)
  {
      unsigned argumentIndex = argumentCount++;
      if (argumentIndex < BankInfo::numberOfArgumentRegisters)
          return Tmp(BankInfo::toArgumentRegister(argumentIndex));
  
      unsigned slotSize;
      if (isARM64() && isDarwin()) {
          // Arguments are packed.
          slotSize = sizeofType(child->type());
      } else {
          // Arguments are aligned.
          slotSize = 8;
      }
  
      stackOffset = WTF::roundUpToMultipleOf(slotSize, stackOffset);
      Arg result = Arg::callArg(stackOffset);
      stackOffset += slotSize;
      return result;
  }
  
  Arg marshallCCallArgument(
      unsigned& gpArgumentCount, unsigned& fpArgumentCount, unsigned& stackOffset, Value* child)
  {
      switch (bankForType(child->type())) {
      case GP:
          return marshallCCallArgumentImpl<GPRInfo>(gpArgumentCount, stackOffset, child);
      case FP:
          return marshallCCallArgumentImpl<FPRInfo>(fpArgumentCount, stackOffset, child);
      }
      RELEASE_ASSERT_NOT_REACHED();
      return Arg();
  }
  
  } // anonymous namespace
  
  Vector<Arg> computeCCallingConvention(Code& code, CCallValue* value)
  {
      Vector<Arg> result;
      result.append(Tmp(CCallSpecial::scratchRegister));
      unsigned gpArgumentCount = 0;
      unsigned fpArgumentCount = 0;
      unsigned stackOffset = 0;
      for (unsigned i = 1; i < value->numChildren(); ++i) {
          result.append(
              marshallCCallArgument(gpArgumentCount, fpArgumentCount, stackOffset, value->child(i)));
      }
      code.requestCallArgAreaSizeInBytes(WTF::roundUpToMultipleOf(stackAlignmentBytes(), stackOffset));
      return result;
  }
  
  Tmp cCallResult(Type type)
  {
      switch (type.kind()) {
      case Void:
          return Tmp();
      case Int32:
      case Int64:
          return Tmp(GPRInfo::returnValueGPR);
      case Float:
      case Double:
          return Tmp(FPRInfo::returnValueFPR);
      case Tuple:
          break;
      }
  
      RELEASE_ASSERT_NOT_REACHED();
      return Tmp();
  }
  
  Inst buildCCall(Code& code, Value* origin, const Vector<Arg>& arguments)
  {
      Inst inst(Patch, origin, Arg::special(code.cCallSpecial()));
      inst.args.append(arguments[0]);
      inst.args.append(Tmp(GPRInfo::returnValueGPR));
      inst.args.append(Tmp(GPRInfo::returnValueGPR2));
      inst.args.append(Tmp(FPRInfo::returnValueFPR));
      for (unsigned i = 1; i < arguments.size(); ++i) {
          Arg arg = arguments[i];
          if (arg.isTmp())
              inst.args.append(arg);
      }
      return inst;
  }
  
  } } } // namespace JSC::B3::Air
  
  #endif // ENABLE(B3_JIT)
  
  