[turbofan] Make new.target explicit in JSCallDescriptor.

src/compiler/linkage.h

 // 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.
 
 #ifndef V8_COMPILER_LINKAGE_H_
 #define V8_COMPILER_LINKAGE_H_
 
 #include "src/base/flags.h"
 #include "src/compiler/frame.h"
 #include "src/compiler/machine-type.h"
@@ skipping 245 matching lines @@
 std::ostream& operator<<(std::ostream& os, const CallDescriptor& d);
 std::ostream& operator<<(std::ostream& os, const CallDescriptor::Kind& k);
 
 // Defines the linkage for a compilation, including the calling conventions
 // for incoming parameters and return value(s) as well as the outgoing calling
 // convention for any kind of call. Linkage is generally architecture-specific.
 //
 // Can be used to translate {arg_index} (i.e. index of the call node input) as
 // well as {param_index} (i.e. as stored in parameter nodes) into an operator
 // representing the architecture-specific location. The following call node
-// layouts are supported (where {n} is the number value inputs):
+// layouts are supported (where {n} is the number of value inputs):
 //
 //                  #0          #1     #2     #3     [...]             #n
 // Call[CodeStub]   code,       arg 1, arg 2, arg 3, [...],            context
-// Call[JSFunction] function,   rcvr,  arg 1, arg 2, [...],      #arg, context
+// Call[JSFunction] function,   rcvr,  arg 1, arg 2, [...], new, #arg, context
 // Call[Runtime]    CEntryStub, arg 1, arg 2, arg 3, [...], fun, #arg, context
 class Linkage : public ZoneObject {
  public:
   explicit Linkage(CallDescriptor* incoming) : incoming_(incoming) {}
 
   static CallDescriptor* ComputeIncoming(Zone* zone, CompilationInfo* info);
 
   // The call descriptor for this compilation unit describes the locations
   // of incoming parameters and the outgoing return value(s).
   CallDescriptor* GetIncomingDescriptor() const { return incoming_; }
@@ skipping 52 matching lines @@
   // calling convention and the specific frame layout, and may thus be
   // architecture-specific. Negative spill slots indicate arguments on the
   // caller's frame.
   FrameOffset GetFrameOffset(int spill_slot, Frame* frame) const;
 
   static int FrameStateInputCount(Runtime::FunctionId function);
 
   // Get the location where an incoming OSR value is stored.
   LinkageLocation GetOsrValueLocation(int index) const;
 
-  // A special parameter index for JSCalls that represents the closure.
-  static const int kJSFunctionCallClosureParamIndex = -1;
+  // A special {Parameter} index for JSCalls that represents the new target.
+  static int GetJSCallNewTargetParamIndex(int parameter_count) {
+    return parameter_count + 0;  // Parameter (arity + 0) is special.
+  }
+
+  // A special {Parameter} index for JSCalls that represents the argument count.
+  static int GetJSCallArgCountParamIndex(int parameter_count) {
+    return parameter_count + 1;  // Parameter (arity + 1) is special.
+  }
+
+  // A special {Parameter} index for JSCalls that represents the context.
+  static int GetJSCallContextParamIndex(int parameter_count) {
+    return parameter_count + 2;  // Parameter (arity + 2) is special.
+  }
+
+  // A special {Parameter} index for JSCalls that represents the closure.
+  static const int kJSCallClosureParamIndex = -1;
 
   // A special {OsrValue} index to indicate the context spill slot.
   static const int kOsrContextSpillSlotIndex = -1;
 
   // Special parameter indices used to pass fixed register data through
   // interpreter dispatches.
   static const int kInterpreterAccumulatorParameter = 0;
   static const int kInterpreterRegisterFileParameter = 1;
   static const int kInterpreterBytecodeOffsetParameter = 2;
   static const int kInterpreterBytecodeArrayParameter = 3;
   static const int kInterpreterDispatchTableParameter = 4;
   static const int kInterpreterContextParameter = 5;
 
  private:
   CallDescriptor* const incoming_;
 
   DISALLOW_COPY_AND_ASSIGN(Linkage);
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_LINKAGE_H_