[ubsan] Fix HeapObjectMatcher to avoid invalid casts.

src/compiler/node-matchers.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_NODE_MATCHERS_H_
 #define V8_COMPILER_NODE_MATCHERS_H_
 
 #include <cmath>
 
 // TODO(turbofan): Move ExternalReference out of assembler.h
@@ skipping 134 matching lines @@
   bool IsNaN() const { return this->HasValue() && std::isnan(this->Value()); }
   bool IsZero() const { return this->Is(0.0) && !std::signbit(this->Value()); }
 };
 
 typedef FloatMatcher<float, IrOpcode::kFloat32Constant> Float32Matcher;
 typedef FloatMatcher<double, IrOpcode::kFloat64Constant> Float64Matcher;
 typedef FloatMatcher<double, IrOpcode::kNumberConstant> NumberMatcher;
 
 
 // A pattern matcher for heap object constants.
-template <typename T>
 struct HeapObjectMatcher final
-    : public ValueMatcher<Unique<T>, IrOpcode::kHeapConstant> {
+    : public ValueMatcher<Unique<HeapObject>, IrOpcode::kHeapConstant> {
   explicit HeapObjectMatcher(Node* node)
-      : ValueMatcher<Unique<T>, IrOpcode::kHeapConstant>(node) {}
+      : ValueMatcher<Unique<HeapObject>, IrOpcode::kHeapConstant>(node) {}
 };
 
 
 // A pattern matcher for external reference constants.
 struct ExternalReferenceMatcher final
     : public ValueMatcher<ExternalReference, IrOpcode::kExternalConstant> {
   explicit ExternalReferenceMatcher(Node* node)
       : ValueMatcher<ExternalReference, IrOpcode::kExternalConstant>(node) {}
 };
 
@@ skipping 421 matching lines @@
   Node* branch_;
   Node* if_true_;
   Node* if_false_;
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_NODE_MATCHERS_H_