From 84326fc49bfd02fc7ac0b4ed14391dc2fa9c4dee Mon Sep 17 00:00:00 2001
From: "Ben L. Titzer" <titzer@chromium.org>
Date: Wed, 17 Jan 2018 15:46:27 +0100
Subject: [PATCH] [wasm] Hide SyncValidate() behind WasmEngine interface.

This is the first in a series of CLs that will separate the JS API
from the implementation of WebAssembly by bottlenecking interactions
through the WasmEngine. In the long run, the JS API and much of V8
should rely only on the WasmEngine interface, which will represent
the "public interface" for embedding WebAssembly.

Next: hide compilation-related methods behind WasmEngine.
Bug: v8:7316
Change-Id: I93404f0dc8a201ae99d30b4c1ca34606e3dddbca
Reviewed-on: https://chromium-review.googlesource.com/868590
Commit-Queue: Ben Titzer <titzer@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50660}
---
 BUILD.gn                          |  1 +
 src/v8.gyp                        |  1 +
 src/wasm/module-compiler.cc       |  7 -------
 src/wasm/module-compiler.h        |  3 ---
 src/wasm/wasm-engine.cc           | 23 +++++++++++++++++++++++
 src/wasm/wasm-engine.h            |  4 +++-
 src/wasm/wasm-js.cc               |  8 +++-----
 test/fuzzer/wasm-fuzzer-common.cc |  4 +++-
 8 files changed, 34 insertions(+), 17 deletions(-)
 create mode 100644 src/wasm/wasm-engine.cc

diff --git a/BUILD.gn b/BUILD.gn
index 3e6575ff3f..5b414f7609 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -2136,6 +2136,7 @@ v8_source_set("v8_base") {
     "src/wasm/wasm-code-wrapper.h",
     "src/wasm/wasm-constants.h",
     "src/wasm/wasm-debug.cc",
+    "src/wasm/wasm-engine.cc",
     "src/wasm/wasm-engine.h",
     "src/wasm/wasm-external-refs.cc",
     "src/wasm/wasm-external-refs.h",
diff --git a/src/v8.gyp b/src/v8.gyp
index 802baeb687..218b173af2 100644
--- a/src/v8.gyp
+++ b/src/v8.gyp
@@ -1486,6 +1486,7 @@
         'wasm/wasm-code-wrapper.h',
         'wasm/wasm-constants.h',
         'wasm/wasm-debug.cc',
+        'wasm/wasm-engine.cc',
         'wasm/wasm-engine.h',
         'wasm/wasm-external-refs.cc',
         'wasm/wasm-external-refs.h',
diff --git a/src/wasm/module-compiler.cc b/src/wasm/module-compiler.cc
index db9ea1a8eb..9b50d7cc9b 100644
--- a/src/wasm/module-compiler.cc
+++ b/src/wasm/module-compiler.cc
@@ -533,13 +533,6 @@ class SetOfNativeModuleModificationScopes final {
 
 }  // namespace
 
-bool SyncValidate(Isolate* isolate, const ModuleWireBytes& bytes) {
-  if (bytes.start() == nullptr || bytes.length() == 0) return false;
-  ModuleResult result = SyncDecodeWasmModule(isolate, bytes.start(),
-                                             bytes.end(), true, kWasmOrigin);
-  return result.ok();
-}
-
 MaybeHandle<WasmModuleObject> SyncCompileTranslatedAsmJs(
     Isolate* isolate, ErrorThrower* thrower, const ModuleWireBytes& bytes,
     Handle<Script> asm_js_script,
diff --git a/src/wasm/module-compiler.h b/src/wasm/module-compiler.h
index 59504328b9..3a8b1972d6 100644
--- a/src/wasm/module-compiler.h
+++ b/src/wasm/module-compiler.h
@@ -23,9 +23,6 @@ namespace wasm {
 class ModuleCompiler;
 class WasmCode;
 
-V8_EXPORT_PRIVATE bool SyncValidate(Isolate* isolate,
-                                    const ModuleWireBytes& bytes);
-
 V8_EXPORT_PRIVATE MaybeHandle<WasmModuleObject> SyncCompileTranslatedAsmJs(
     Isolate* isolate, ErrorThrower* thrower, const ModuleWireBytes& bytes,
     Handle<Script> asm_js_script, Vector<const byte> asm_js_offset_table_bytes);
diff --git a/src/wasm/wasm-engine.cc b/src/wasm/wasm-engine.cc
new file mode 100644
index 0000000000..4c84b70dbd
--- /dev/null
+++ b/src/wasm/wasm-engine.cc
@@ -0,0 +1,23 @@
+// Copyright 2018 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/wasm/wasm-engine.h"
+#include "src/objects-inl.h"
+#include "src/wasm/module-compiler.h"
+
+namespace v8 {
+namespace internal {
+namespace wasm {
+
+bool WasmEngine::SyncValidate(Isolate* isolate, const ModuleWireBytes& bytes) {
+  // TODO(titzer): remove dependency on the isolate.
+  if (bytes.start() == nullptr || bytes.length() == 0) return false;
+  ModuleResult result = SyncDecodeWasmModule(isolate, bytes.start(),
+                                             bytes.end(), true, kWasmOrigin);
+  return result.ok();
+}
+
+}  // namespace wasm
+}  // namespace internal
+}  // namespace v8
diff --git a/src/wasm/wasm-engine.h b/src/wasm/wasm-engine.h
index 665663173f..bf06b47ed7 100644
--- a/src/wasm/wasm-engine.h
+++ b/src/wasm/wasm-engine.h
@@ -18,11 +18,13 @@ namespace wasm {
 
 // The central data structure that represents an engine instance capable of
 // loading, instantiating, and executing WASM code.
-class WasmEngine {
+class V8_EXPORT_PRIVATE WasmEngine {
  public:
   explicit WasmEngine(std::unique_ptr<WasmCodeManager> code_manager)
       : code_manager_(std::move(code_manager)) {}
 
+  bool SyncValidate(Isolate* isolate, const ModuleWireBytes& bytes);
+
   CompilationManager* compilation_manager() { return &compilation_manager_; }
 
   WasmCodeManager* code_manager() const { return code_manager_.get(); }
diff --git a/src/wasm/wasm-js.cc b/src/wasm/wasm-js.cc
index d46a32b97c..ce2bf42455 100644
--- a/src/wasm/wasm-js.cc
+++ b/src/wasm/wasm-js.cc
@@ -17,13 +17,11 @@
 #include "src/parsing/parse-info.h"
 #include "src/trap-handler/trap-handler.h"
 #include "src/wasm/module-compiler.h"
-#include "src/wasm/module-decoder.h"
 #include "src/wasm/wasm-api.h"
+#include "src/wasm/wasm-engine.h"
 #include "src/wasm/wasm-limits.h"
 #include "src/wasm/wasm-memory.h"
-#include "src/wasm/wasm-module.h"
 #include "src/wasm/wasm-objects-inl.h"
-#include "src/wasm/wasm-result.h"
 
 using v8::internal::wasm::ErrorThrower;
 
@@ -195,10 +193,10 @@ void WebAssemblyValidate(const v8::FunctionCallbackInfo<v8::Value>& args) {
     memcpy(copy.get(), bytes.start(), bytes.length());
     i::wasm::ModuleWireBytes bytes_copy(copy.get(),
                                         copy.get() + bytes.length());
-    validated = i::wasm::SyncValidate(i_isolate, bytes_copy);
+    validated = i_isolate->wasm_engine()->SyncValidate(i_isolate, bytes_copy);
   } else {
     // The wire bytes are not shared, OK to use them directly.
-    validated = i::wasm::SyncValidate(i_isolate, bytes);
+    validated = i_isolate->wasm_engine()->SyncValidate(i_isolate, bytes);
   }
 
   return_value.Set(Boolean::New(isolate, validated));
diff --git a/test/fuzzer/wasm-fuzzer-common.cc b/test/fuzzer/wasm-fuzzer-common.cc
index cc1c11e469..46f5133486 100644
--- a/test/fuzzer/wasm-fuzzer-common.cc
+++ b/test/fuzzer/wasm-fuzzer-common.cc
@@ -9,6 +9,7 @@
 #include "src/objects-inl.h"
 #include "src/wasm/module-compiler.h"
 #include "src/wasm/wasm-api.h"
+#include "src/wasm/wasm-engine.h"
 #include "src/wasm/wasm-module-builder.h"
 #include "src/wasm/wasm-module.h"
 #include "src/zone/accounting-allocator.h"
@@ -248,7 +249,8 @@ int WasmExecutionFuzzer::FuzzWasmModule(const uint8_t* data, size_t size,
     GenerateTestCase(i_isolate, wire_bytes, compiles);
   }
 
-  bool validates = SyncValidate(i_isolate, wire_bytes);
+  bool validates =
+      i_isolate->wasm_engine()->SyncValidate(i_isolate, wire_bytes);
 
   CHECK_EQ(compiles, validates);
   CHECK_IMPLIES(require_valid, validates);