Make start node a value input to parameter nodes.

src/compiler/common-operator.h

 // Copyright 2013 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_COMMON_OPERATOR_H_
 #define V8_COMPILER_COMMON_OPERATOR_H_
 
 #include "src/v8.h"
 
 #include "src/assembler.h"
@@ skipping 47 matching lines @@
 // including JavaScript, mid-level, and low-level.
 // TODO(titzer): Move the mnemonics into SimpleOperator and Operator1 classes.
 class CommonOperatorBuilder {
  public:
   explicit CommonOperatorBuilder(Zone* zone) : zone_(zone) {}
 
 #define CONTROL_OP(name, inputs, controls)                                   \
   return new (zone_) ControlOperator(IrOpcode::k##name, Operator::kFoldable, \
                                      inputs, 0, controls, #name);
 
-  Operator* Start() { CONTROL_OP(Start, 0, 0); }
+  Operator* Start(int num_formal_parameters) {
+    // Outputs are formal parameters, plus context, receiver, and JSFunction.
+    int outputs = num_formal_parameters + 3;
+    return new (zone_) ControlOperator(IrOpcode::kStart, Operator::kFoldable, 0,
+                                       outputs, 0, "Start");
+  }
   Operator* Dead() { CONTROL_OP(Dead, 0, 0); }
   Operator* End() { CONTROL_OP(End, 0, 1); }
   Operator* Branch() { CONTROL_OP(Branch, 1, 1); }
   Operator* IfTrue() { CONTROL_OP(IfTrue, 0, 1); }
   Operator* IfFalse() { CONTROL_OP(IfFalse, 0, 1); }
   Operator* Throw() { CONTROL_OP(Throw, 1, 1); }
   Operator* LazyDeoptimization() { CONTROL_OP(LazyDeoptimization, 0, 1); }
   Operator* Continuation() { CONTROL_OP(Continuation, 0, 1); }
 
   Operator* Deoptimize() {
     return new (zone_)
         ControlOperator(IrOpcode::kDeoptimize, 0, 1, 0, 1, "Deoptimize");
   }
 
   Operator* Return() {
     return new (zone_) ControlOperator(IrOpcode::kReturn, 0, 1, 0, 1, "Return");
   }
 
   Operator* Merge(int controls) {
     return new (zone_) ControlOperator(IrOpcode::kMerge, Operator::kFoldable, 0,
                                        0, controls, "Merge");
   }
 
   Operator* Loop(int controls) {
     return new (zone_) ControlOperator(IrOpcode::kLoop, Operator::kFoldable, 0,
                                        0, controls, "Loop");
   }
 
   Operator* Parameter(int index) {
-    return new (zone_) Operator1<int>(IrOpcode::kParameter, Operator::kPure, 0,
+    return new (zone_) Operator1<int>(IrOpcode::kParameter, Operator::kPure, 1,
                                       1, "Parameter", index);
   }
   Operator* Int32Constant(int32_t value) {
     return new (zone_) Operator1<int>(IrOpcode::kInt32Constant, Operator::kPure,
                                       0, 1, "Int32Constant", value);
   }
   Operator* Int64Constant(int64_t value) {
     return new (zone_)
         Operator1<int64_t>(IrOpcode::kInt64Constant, Operator::kPure, 0, 1,
                            "Int64Constant", value);
@@ skipping 168 matching lines @@
 
 template <typename T>
 inline T ValueOf(Operator* op) {
   return CommonOperatorTraits<T>::ValueOf(op);
 }
 }
 }
 }  // namespace v8::internal::compiler
 
 #endif  // V8_COMPILER_COMMON_OPERATOR_H_