[wasm] Use a Managed<WasmModule> to hold metadata about modules.

src/compiler/wasm-compiler.cc

 // Copyright 2015 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/wasm-compiler.h"
 
 #include <memory>
 
 #include "src/isolate-inl.h"
 
@@ skipping 2139 matching lines @@
   {
     Node* load_sig = graph()->NewNode(
         machine->Load(MachineType::AnyTagged()), table,
         graph()->NewNode(machine->Int32Add(),
                          graph()->NewNode(machine->Word32Shl(), key,
                                           Int32Constant(kPointerSizeLog2)),
                          Int32Constant(fixed_offset)),
         *effect_, *control_);
     int32_t key = module_->module->function_tables[0].map.Find(sig);
     DCHECK_GE(key, 0);
-    Node* sig_match =
-        graph()->NewNode(machine->Word32Equal(),
-                         BuildChangeSmiToInt32(load_sig), Int32Constant(key));
+    Node* sig_match = graph()->NewNode(machine->WordEqual(), load_sig,

[Mircea Trofin, 2016/10/15 17:38:39]

Is this related, or can it be a separate CL?

+                                       jsgraph()->SmiConstant(key));
     trap_->AddTrapIfFalse(wasm::kTrapFuncSigMismatch, sig_match, position);
   }
 
   // Load code object from the table.
   uint32_t offset = fixed_offset + kPointerSize * table_size;
   Node* load_code = graph()->NewNode(
       machine->Load(MachineType::AnyTagged()), table,
       graph()->NewNode(machine->Int32Add(),
                        graph()->NewNode(machine->Word32Shl(), key,
                                         Int32Constant(kPointerSizeLog2)),
@@ skipping 1243 matching lines @@
                             function_->code_start_offset),
            compile_ms);
   }
 
   return code;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8