[turbofan] First step towards sanitizing for-in and making it optimizable.

src/compiler/verifier.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/compiler/verifier.h"
 
 #include <algorithm>
 #include <deque>
 #include <queue>
 #include <sstream>
@@ skipping 546 matching lines @@
       // Type is Receiver.
       CheckUpperIs(node, Type::Receiver());
       break;
     case IrOpcode::kJSCallFunction:
     case IrOpcode::kJSCallRuntime:
     case IrOpcode::kJSYield:
       // Type can be anything.
       CheckUpperIs(node, Type::Any());
       break;
 
+    case IrOpcode::kJSForInPrepare: {
+      // TODO(bmeurer): What are the constraints on thse?
+      CheckUpperIs(node, Type::Any());
+      break;
+    }
+    case IrOpcode::kJSForInDone: {
+      CheckValueInputIs(node, 0, Type::UnsignedSmall());
+      break;
+    }
+    case IrOpcode::kJSForInNext: {
+      CheckUpperIs(node, Type::Union(Type::Name(), Type::Undefined()));
+      break;
+    }
+    case IrOpcode::kJSForInStep: {
+      CheckValueInputIs(node, 0, Type::UnsignedSmall());
+      CheckUpperIs(node, Type::UnsignedSmall());
+      break;
+    }
+
     case IrOpcode::kJSStackCheck:
       // Type is empty.
       CheckNotTyped(node);
       break;
 
     // Simplified operators
     // -------------------------------
     case IrOpcode::kBooleanNot:
       // Boolean -> Boolean
       CheckValueInputIs(node, 0, Type::Boolean());
@@ skipping 525 matching lines @@
     // Check inputs for all nodes in the block.
     for (size_t i = 0; i < block->NodeCount(); i++) {
       Node* node = block->NodeAt(i);
       CheckInputsDominate(schedule, block, node, static_cast<int>(i) - 1);
     }
   }
 }
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8