[wasm] Add timer to measure asm->wasm translation

src/asmjs/asm-wasm-builder.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/v8.h"
 
 // Required to get M_E etc. in MSVC.
 #if defined(_WIN32)
 #define _USE_MATH_DEFINES
 #endif
@@ skipping 1976 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(AsmWasmBuilderImpl);
 };
 
 AsmWasmBuilder::AsmWasmBuilder(CompilationInfo* info)
     : info_(info),
       typer_(info->isolate(), info->zone(), info->script(), info->literal()) {}
 
 // TODO(aseemgarg): probably should take zone (to write wasm to) as input so
 // that zone in constructor may be thrown away once wasm module is written.
 AsmWasmBuilder::Result AsmWasmBuilder::Run(Handle<FixedArray>* foreign_args) {
+  HistogramTimerScope asm_wasm_time_scope(
+      info_->isolate()->counters()->asm_wasm_translation_time());
+
   Zone* zone = info_->zone();
   AsmWasmBuilderImpl impl(info_->isolate(), zone, info_,
                           info_->parse_info()->ast_value_factory(),
                           info_->script(), info_->literal(), &typer_);
   bool success = impl.Build();
   *foreign_args = impl.GetForeignArgs();
   ZoneBuffer* module_buffer = new (zone) ZoneBuffer(zone);
   impl.builder_->WriteTo(*module_buffer);
   ZoneBuffer* asm_offsets_buffer = new (zone) ZoneBuffer(zone);
   impl.builder_->WriteAsmJsOffsetTable(*asm_offsets_buffer);
   return {module_buffer, asm_offsets_buffer, success};
 }
 
 const char* AsmWasmBuilder::foreign_init_name = "__foreign_init__";
 const char* AsmWasmBuilder::single_function_name = "__single_function__";
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8