text: // 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/code-stubs.h"
  #include "src/compiler.h"
  #include "src/compiler/linkage.h"
  #include "src/compiler/node.h"
  #include "src/compiler/pipeline.h"
  #include "src/scopes.h"
  
  namespace v8 {
  namespace internal {
  namespace compiler {
  
  
  std::ostream& operator<<(std::ostream& os, const CallDescriptor::Kind& k) {
    switch (k) {
      case CallDescriptor::kCallCodeObject:
        os << "Code";
        break;
      case CallDescriptor::kCallJSFunction:
        os << "JS";
        break;
      case CallDescriptor::kCallAddress:
        os << "Addr";
        break;
    }
    return os;
  }
  
  
  std::ostream& operator<<(std::ostream& os, const CallDescriptor& d) {
    // TODO(svenpanne) Output properties etc. and be less cryptic.
    return os << d.kind() << ":" << d.debug_name() << ":r" << d.ReturnCount()
              << "j" << d.JSParameterCount() << "i" << d.InputCount() << "f"
              << d.FrameStateCount() << "t" << d.SupportsTailCalls();
  }
  
  
  bool CallDescriptor::HasSameReturnLocationsAs(
      const CallDescriptor* other) const {
    if (ReturnCount() != other->ReturnCount()) return false;
    for (size_t i = 0; i < ReturnCount(); ++i) {
      if (GetReturnLocation(i) != other->GetReturnLocation(i)) return false;
    }
    return true;
  }
  
  
  CallDescriptor* Linkage::ComputeIncoming(Zone* zone, CompilationInfo* info) {
    if (info->code_stub() != NULL) {
      // Use the code stub interface descriptor.
      CodeStub* stub = info->code_stub();
      CallInterfaceDescriptor descriptor = stub->GetCallInterfaceDescriptor();
      return GetStubCallDescriptor(
          info->isolate(), zone, descriptor, stub->GetStackParameterCount(),
          CallDescriptor::kNoFlags, Operator::kNoProperties);
    }
    if (info->function() != NULL) {
      // If we already have the function literal, use the number of parameters
      // plus the receiver.
      return GetJSCallDescriptor(zone, info->is_osr(),
                                 1 + info->function()->parameter_count(),
                                 CallDescriptor::kNoFlags);
    }
    if (!info->closure().is_null()) {
      // If we are compiling a JS function, use a JS call descriptor,
      // plus the receiver.
      SharedFunctionInfo* shared = info->closure()->shared();
      return GetJSCallDescriptor(zone, info->is_osr(),
                                 1 + shared->internal_formal_parameter_count(),
                                 CallDescriptor::kNoFlags);
    }
    return NULL;  // TODO(titzer): ?
  }
  
  
  FrameOffset Linkage::GetFrameOffset(int spill_slot, Frame* frame,
                                      int extra) const {
    if (frame->GetSpillSlotCount() > 0 || incoming_->IsJSFunctionCall() ||
        incoming_->kind() == CallDescriptor::kCallAddress) {
      int offset;
      int register_save_area_size = frame->GetRegisterSaveAreaSize();
      if (spill_slot >= 0) {
        // Local or spill slot. Skip the frame pointer, function, and
        // context in the fixed part of the frame.
        offset =
            -(spill_slot + 1) * kPointerSize - register_save_area_size + extra;
      } else {
        // Incoming parameter. Skip the return address.
        offset = -(spill_slot + 1) * kPointerSize + kFPOnStackSize +
                 kPCOnStackSize + extra;
      }
      return FrameOffset::FromFramePointer(offset);
    } else {
      // No frame. Retrieve all parameters relative to stack pointer.
      DCHECK(spill_slot < 0);  // Must be a parameter.
      int register_save_area_size = frame->GetRegisterSaveAreaSize();
      int offset = register_save_area_size - (spill_slot + 1) * kPointerSize +
                   kPCOnStackSize + extra;
      return FrameOffset::FromStackPointer(offset);
    }
  }
  
  
  // static
  int Linkage::FrameStateInputCount(Runtime::FunctionId function) {
    // Most runtime functions need a FrameState. A few chosen ones that we know
    // not to call into arbitrary JavaScript, not to throw, and not to deoptimize
    // are blacklisted here and can be called without a FrameState.
    switch (function) {
      case Runtime::kAllocateInTargetSpace:
      case Runtime::kDateField:
      case Runtime::kDefineClassMethod:              // TODO(jarin): Is it safe?
      case Runtime::kDefineGetterPropertyUnchecked:  // TODO(jarin): Is it safe?
      case Runtime::kDefineSetterPropertyUnchecked:  // TODO(jarin): Is it safe?
      case Runtime::kForInDone:
      case Runtime::kForInStep:
      case Runtime::kNewArguments:
      case Runtime::kNewClosure:
      case Runtime::kNewFunctionContext:
      case Runtime::kNewRestParamSlow:
      case Runtime::kPushBlockContext:
      case Runtime::kPushCatchContext:
      case Runtime::kReThrow:
      case Runtime::kStringCompareRT:
      case Runtime::kStringEquals:
      case Runtime::kToFastProperties:  // TODO(jarin): Is it safe?
      case Runtime::kTraceEnter:
      case Runtime::kTraceExit:
        return 0;
      case Runtime::kInlineArguments:
      case Runtime::kInlineCallFunction:
      case Runtime::kInlineGetCallerJSFunction:
      case Runtime::kInlineGetPrototype:
      case Runtime::kInlineRegExpExec:
        return 1;
      case Runtime::kInlineDeoptimizeNow:
      case Runtime::kInlineThrowNotDateError:
        return 2;
      default:
        break;
    }
  
    // Most inlined runtime functions (except the ones listed above) can be called
    // without a FrameState or will be lowered by JSIntrinsicLowering internally.
    const Runtime::Function* const f = Runtime::FunctionForId(function);
    if (f->intrinsic_type == Runtime::IntrinsicType::INLINE) return 0;
  
    return 1;
  }
  
  
  bool CallDescriptor::UsesOnlyRegisters() const {
    for (size_t i = 0; i < InputCount(); ++i) {
      if (!GetInputLocation(i).is_register()) return false;
    }
    for (size_t i = 0; i < ReturnCount(); ++i) {
      if (!GetReturnLocation(i).is_register()) return false;
    }
    return true;
  }
  
  
  //==============================================================================
  // Provide unimplemented methods on unsupported architectures, to at least link.
  //==============================================================================
  #if !V8_TURBOFAN_BACKEND
  CallDescriptor* Linkage::GetJSCallDescriptor(Zone* zone, bool is_osr,
                                               int parameter_count,
                                               CallDescriptor::Flags flags) {
    UNIMPLEMENTED();
    return NULL;
  }
  
  
  LinkageLocation Linkage::GetOsrValueLocation(int index) const {
    UNIMPLEMENTED();
    return LinkageLocation(-1);  // Dummy value
  }
  
  
  CallDescriptor* Linkage::GetRuntimeCallDescriptor(
      Zone* zone, Runtime::FunctionId function, int parameter_count,
      Operator::Properties properties) {
    UNIMPLEMENTED();
    return NULL;
  }
  
  
  CallDescriptor* Linkage::GetStubCallDescriptor(
      Isolate* isolate, Zone* zone, const CallInterfaceDescriptor& descriptor,
      int stack_parameter_count, CallDescriptor::Flags flags,
      Operator::Properties properties, MachineType return_type) {
    UNIMPLEMENTED();
    return NULL;
  }
  
  
  CallDescriptor* Linkage::GetSimplifiedCDescriptor(Zone* zone,
                                                    const MachineSignature* sig) {
    UNIMPLEMENTED();
    return NULL;
  }
  #endif  // !V8_TURBOFAN_BACKEND
  }  // namespace compiler
  }  // namespace internal
  }  // namespace v8
  