Remove funky 2-stage initialization of ParserInfo and an adventurous memset.

src/hydrogen.cc

 // 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.
 
 #include "src/hydrogen.h"
 
 #include <sstream>
 
 #include "src/v8.h"
 
@@ skipping 7830 matching lines @@
   // Always inline small methods (<= 10 nodes).
   if (inlined_count_ > Min(FLAG_max_inlined_nodes_cumulative,
                            kUnlimitedMaxInlinedNodesCumulative)) {
     TraceInline(target, caller, "cumulative AST node limit reached");
     return false;
   }
 
   // Parse and allocate variables.
   // Use the same AstValueFactory for creating strings in the sub-compilation
   // step, but don't transfer ownership to target_info.
-  ParseInfo parse_info(zone());
-  parse_info.InitializeFromJSFunction(target);
+  ParseInfo parse_info(zone(), target);
   parse_info.set_ast_value_factory(
       top_info()->parse_info()->ast_value_factory());
   parse_info.set_ast_value_factory_owned(false);
 
   CompilationInfo target_info(&parse_info);
   Handle<SharedFunctionInfo> target_shared(target->shared());
   if (!Compiler::ParseAndAnalyze(target_info.parse_info())) {
     if (target_info.isolate()->has_pending_exception()) {
       // Parse or scope error, never optimize this function.
       SetStackOverflow();
@@ skipping 5517 matching lines @@
   if (ShouldProduceTraceOutput()) {
     isolate()->GetHTracer()->TraceHydrogen(name(), graph_);
   }
 
 #ifdef DEBUG
   graph_->Verify(false);  // No full verify.
 #endif
 }
 
 } }  // namespace v8::internal