Lazily initialize fast_sqrt() and pass an Isolate parameter to it

src/v8.cc

 // Copyright 2012 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"
 
 #include "src/assembler.h"
 #include "src/base/once.h"
 #include "src/base/platform/platform.h"
 #include "src/bootstrapper.h"
@@ skipping 62 matching lines @@
     FlagList::SetFlagsFromString(filter_flag, StrLength(filter_flag));
   }
 
   base::OS::Initialize(FLAG_random_seed, FLAG_hard_abort, FLAG_gc_fake_mmap);
 
   Isolate::InitializeOncePerProcess();
 
   Sampler::SetUp();
   CpuFeatures::Probe(false);
   init_memcopy_functions();
-  // The custom exp implementation needs 16KB of lookup data; initialize it
-  // on demand.
-  init_fast_sqrt_function();
 #ifdef _WIN64
   init_modulo_function();
 #endif
   ElementsAccessor::InitializeOncePerProcess();
   LOperand::SetUpCaches();
   SetUpJSCallerSavedCodeData();
   ExternalReference::SetUp();
   Bootstrapper::InitializeOncePerProcess();
 }
 
@@ skipping 36 matching lines @@
 
 void V8::SetSnapshotBlob(StartupData* snapshot_blob) {
 #ifdef V8_USE_EXTERNAL_STARTUP_DATA
   base::CallOnce(&init_snapshot_once, &SetSnapshotFromFile, snapshot_blob);
 #else
   CHECK(false);
 #endif
 }
 }  // namespace internal
 }  // namespace v8