[wasm] [asm.js] Avoid expensive GetLineNumber up front in asm-typer.

src/asmjs/asm-typer.cc

 // Copyright 2016 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/asmjs/asm-typer.h"
 
 #include <algorithm>
 #include <limits>
 #include <memory>
 #include <string>
@@ skipping 171 matching lines @@
       forward_definitions_(zone),
       ffi_use_signatures_(zone),
       stdlib_types_(zone),
       stdlib_math_types_(zone),
       module_info_(VariableInfo::ForSpecialSymbol(zone_, kModule)),
       global_scope_(ZoneHashMap::kDefaultHashMapCapacity,
                     ZoneAllocationPolicy(zone)),
       local_scope_(ZoneHashMap::kDefaultHashMapCapacity,
                    ZoneAllocationPolicy(zone)),
       stack_limit_(isolate->stack_guard()->real_climit()),
-      module_node_types_(zone_),
-      function_node_types_(zone_),
       fround_type_(AsmType::FroundType(zone_)),
       ffi_type_(AsmType::FFIType(zone_)),
       function_pointer_tables_(zone_) {
   InitializeStdlib();
 }
 
 namespace {
 bool ValidAsmIdentifier(Handle<String> name) {
   static const char* kInvalidAsmNames[] = {"eval", "arguments"};
 
@@ skipping 188 matching lines @@
 
   if (entry == nullptr && !module_name_.is_null() &&
       module_name_->Equals(*variable->name())) {
     return module_info_;
   }
 
   return entry ? reinterpret_cast<VariableInfo*>(entry->value) : nullptr;
 }
 
 void AsmTyper::AddForwardReference(VariableProxy* proxy, VariableInfo* info) {
-  info->SetFirstForwardUse(proxy->position() == kNoSourcePosition
-                               ? -1
-                               : script_->GetLineNumber(proxy->position()));
+  info->SetFirstForwardUse(proxy->position());
   forward_definitions_.push_back(info);
 }
 
 bool AsmTyper::AddGlobal(Variable* variable, VariableInfo* info) {
   // We can't DCHECK(!in_function_) because function may actually install global
   // names (forward defined functions and function tables.)
   DCHECK(info->mutability() != VariableInfo::kInvalidMutability);
   DCHECK(info->IsGlobal());
   DCHECK(ValidAsmIdentifier(variable->name()));
 
@@ skipping 287 matching lines @@
     }
   }
 
   // 6.2 ValidateExport
   if (module_return_ == nullptr) {
     FAIL(fun, "Missing asm.js module export.");
   }
 
   for (auto* forward_def : forward_definitions_) {
     if (forward_def->missing_definition()) {
-      FAIL_LINE(forward_def->source_location(),
-                "Missing definition for forward declared identifier.");
+      int position = forward_def->source_location();
+      int line =
+          position == kNoSourcePosition ? -1 : script_->GetLineNumber(position);
+
+      FAIL_LINE(line, "Missing definition for forward declared identifier.");
     }
   }
 
   RECURSE(ValidateExport(module_return_));
 
   if (!source_layout_.IsValid()) {
     FAIL(fun, "Invalid asm.js source code layout.");
   }
 
   return AsmType::Int();  // Any type that is not AsmType::None();
@@ skipping 2154 matching lines @@
     return true;
   }
 
   *error_message = typer.error_message();
   return false;
 }
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8