Use MaybeHandle for values that could be empty

This fixes some of the old legacy API that used empty Handle<>

Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I861e31a4a6f65bc497bfc512174adba39c17abca
Reviewed-on: https://chromium-review.googlesource.com/701634Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48311}

src/api.cc

@@ -2305,9 +2305,9 @@ MaybeLocal<UnboundScript> ScriptCompiler::CompileUnboundInternal(
   {
     i::HistogramTimerScope total(isolate->counters()->compile_script(), true);
     TRACE_EVENT0(TRACE_DISABLED_BY_DEFAULT("v8.compile"), "V8.CompileScript");
-    i::Handle<i::Object> name_obj;
-    i::Handle<i::Object> source_map_url;
-    i::Handle<i::FixedArray> host_defined_options =
+    i::MaybeHandle<i::Object> name_obj;
+    i::MaybeHandle<i::Object> source_map_url;
+    i::MaybeHandle<i::FixedArray> host_defined_options =
         isolate->factory()->empty_fixed_array();
     int line_offset = 0;
     int column_offset = 0;
@@ -2327,11 +2327,12 @@ MaybeLocal<UnboundScript> ScriptCompiler::CompileUnboundInternal(
     if (!source->source_map_url.IsEmpty()) {
       source_map_url = Utils::OpenHandle(*(source->source_map_url));
     }
-    result = i::Compiler::GetSharedFunctionInfoForScript(
-        str, name_obj, line_offset, column_offset, source->resource_options,
-        source_map_url, isolate->native_context(), NULL, &script_data, options,
-        i::NOT_NATIVES_CODE, host_defined_options);
-    has_pending_exception = result.is_null();
+    i::MaybeHandle<i::SharedFunctionInfo> maybe_function_info =
+        i::Compiler::GetSharedFunctionInfoForScript(
+            str, name_obj, line_offset, column_offset, source->resource_options,
+            source_map_url, isolate->native_context(), NULL, &script_data,
+            options, i::NOT_NATIVES_CODE, host_defined_options);
+    has_pending_exception = !maybe_function_info.ToHandle(&result);
     if (has_pending_exception && script_data != NULL) {
       // This case won't happen during normal operation; we have compiled
       // successfully and produced cached data, and but the second compilation
@@ -9963,14 +9964,15 @@ MaybeLocal<UnboundScript> debug::CompileInspectorScript(Isolate* v8_isolate,
   i::Handle<i::SharedFunctionInfo> result;
   {
     ScriptOriginOptions origin_options;
-    result = i::Compiler::GetSharedFunctionInfoForScript(
-        str, i::Handle<i::Object>(), 0, 0, origin_options,
-        i::Handle<i::Object>(), isolate->native_context(), NULL, &script_data,
-        ScriptCompiler::kNoCompileOptions,
-        i::FLAG_expose_inspector_scripts ? i::NOT_NATIVES_CODE
-                                         : i::INSPECTOR_CODE,
-        i::Handle<i::FixedArray>());
-    has_pending_exception = result.is_null();
+    i::MaybeHandle<i::SharedFunctionInfo> maybe_function_info =
+        i::Compiler::GetSharedFunctionInfoForScript(
+            str, i::MaybeHandle<i::Object>(), 0, 0, origin_options,
+            i::MaybeHandle<i::Object>(), isolate->native_context(), NULL,
+            &script_data, ScriptCompiler::kNoCompileOptions,
+            i::FLAG_expose_inspector_scripts ? i::NOT_NATIVES_CODE
+                                             : i::INSPECTOR_CODE,
+            i::MaybeHandle<i::FixedArray>());
+    has_pending_exception = !maybe_function_info.ToHandle(&result);
     RETURN_ON_FAILED_EXECUTION(UnboundScript);
   }
   RETURN_ESCAPED(ToApiHandle<UnboundScript>(result));

src/bootstrapper.cc

@@ -3627,12 +3627,14 @@ bool Bootstrapper::CompileNative(Isolate* isolate, Vector<const char> name,
 
   Handle<String> script_name =
       isolate->factory()->NewStringFromUtf8(name).ToHandleChecked();
-  Handle<SharedFunctionInfo> function_info =
+  MaybeHandle<SharedFunctionInfo> maybe_function_info =
       Compiler::GetSharedFunctionInfoForScript(
-          source, script_name, 0, 0, ScriptOriginOptions(), Handle<Object>(),
-          context, NULL, NULL, ScriptCompiler::kNoCompileOptions, natives_flag,
-          Handle<FixedArray>());
-  if (function_info.is_null()) return false;
+          source, script_name, 0, 0, ScriptOriginOptions(),
+          MaybeHandle<Object>(), context, NULL, NULL,
+          ScriptCompiler::kNoCompileOptions, natives_flag,
+          MaybeHandle<FixedArray>());
+  Handle<SharedFunctionInfo> function_info;
+  if (!maybe_function_info.ToHandle(&function_info)) return false;
 
   DCHECK(context->IsNativeContext());
 
@@ -3691,11 +3693,13 @@ bool Genesis::CompileExtension(Isolate* isolate, v8::Extension* extension) {
   if (!cache->Lookup(name, &function_info)) {
     Handle<String> script_name =
         factory->NewStringFromUtf8(name).ToHandleChecked();
-    function_info = Compiler::GetSharedFunctionInfoForScript(
-        source, script_name, 0, 0, ScriptOriginOptions(), Handle<Object>(),
-        context, extension, NULL, ScriptCompiler::kNoCompileOptions,
-        EXTENSION_CODE, Handle<FixedArray>());
-    if (function_info.is_null()) return false;
+    MaybeHandle<SharedFunctionInfo> maybe_function_info =
+        Compiler::GetSharedFunctionInfoForScript(
+            source, script_name, 0, 0, ScriptOriginOptions(),
+            MaybeHandle<Object>(), context, extension, NULL,
+            ScriptCompiler::kNoCompileOptions, EXTENSION_CODE,
+            MaybeHandle<FixedArray>());
+    if (!maybe_function_info.ToHandle(&function_info)) return false;
     cache->Add(name, function_info);
   }
 

src/compilation-cache.cc

@@ -95,14 +95,15 @@ CompilationCacheScript::CompilationCacheScript(Isolate* isolate)
 // script originates from the same place. This is to avoid issues
 // when reporting errors, etc.
 bool CompilationCacheScript::HasOrigin(Handle<SharedFunctionInfo> function_info,
-                                       Handle<Object> name, int line_offset,
-                                       int column_offset,
+                                       MaybeHandle<Object> maybe_name,
+                                       int line_offset, int column_offset,
                                        ScriptOriginOptions resource_options) {
   Handle<Script> script =
       Handle<Script>(Script::cast(function_info->script()), isolate());
   // If the script name isn't set, the boilerplate script should have
   // an undefined name to have the same origin.
-  if (name.is_null()) {
+  Handle<Object> name;
+  if (!maybe_name.ToHandle(&name)) {
     return script->name()->IsUndefined(isolate());
   }
   // Do the fast bailout checks first.
@@ -123,7 +124,7 @@ bool CompilationCacheScript::HasOrigin(Handle<SharedFunctionInfo> function_info,
 // will be cached, but subsequent code from different source / line
 // won't.
 InfoVectorPair CompilationCacheScript::Lookup(
-    Handle<String> source, Handle<Object> name, int line_offset,
+    Handle<String> source, MaybeHandle<Object> name, int line_offset,
     int column_offset, ScriptOriginOptions resource_options,
     Handle<Context> context, LanguageMode language_mode) {
   InfoVectorPair result;
@@ -263,7 +264,7 @@ void CompilationCache::Remove(Handle<SharedFunctionInfo> function_info) {
 }
 
 InfoVectorPair CompilationCache::LookupScript(
-    Handle<String> source, Handle<Object> name, int line_offset,
+    Handle<String> source, MaybeHandle<Object> name, int line_offset,
     int column_offset, ScriptOriginOptions resource_options,
     Handle<Context> context, LanguageMode language_mode) {
   InfoVectorPair empty_result;

src/compilation-cache.h

@@ -79,7 +79,7 @@ class CompilationCacheScript : public CompilationSubCache {
  public:
   explicit CompilationCacheScript(Isolate* isolate);
 
-  InfoVectorPair Lookup(Handle<String> source, Handle<Object> name,
+  InfoVectorPair Lookup(Handle<String> source, MaybeHandle<Object> name,
                         int line_offset, int column_offset,
                         ScriptOriginOptions resource_options,
                         Handle<Context> context, LanguageMode language_mode);
@@ -89,8 +89,8 @@ class CompilationCacheScript : public CompilationSubCache {
            Handle<Cell> literals);
 
  private:
-  bool HasOrigin(Handle<SharedFunctionInfo> function_info, Handle<Object> name,
-                 int line_offset, int column_offset,
+  bool HasOrigin(Handle<SharedFunctionInfo> function_info,
+                 MaybeHandle<Object> name, int line_offset, int column_offset,
                  ScriptOriginOptions resource_options);
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(CompilationCacheScript);
@@ -152,7 +152,7 @@ class CompilationCache {
   // Finds the script shared function info for a source
   // string. Returns an empty handle if the cache doesn't contain a
   // script for the given source string with the right origin.
-  InfoVectorPair LookupScript(Handle<String> source, Handle<Object> name,
+  InfoVectorPair LookupScript(Handle<String> source, MaybeHandle<Object> name,
                               int line_offset, int column_offset,
                               ScriptOriginOptions resource_options,
                               Handle<Context> context,

src/compiler.cc

@@ -1208,13 +1208,13 @@ MaybeHandle<JSFunction> Compiler::GetFunctionFromString(
                                        eval_scope_position, eval_position);
 }
 
-Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
-    Handle<String> source, Handle<Object> script_name, int line_offset,
-    int column_offset, ScriptOriginOptions resource_options,
-    Handle<Object> source_map_url, Handle<Context> context,
+MaybeHandle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
+    Handle<String> source, MaybeHandle<Object> maybe_script_name,
+    int line_offset, int column_offset, ScriptOriginOptions resource_options,
+    MaybeHandle<Object> maybe_source_map_url, Handle<Context> context,
     v8::Extension* extension, ScriptData** cached_data,
     ScriptCompiler::CompileOptions compile_options, NativesFlag natives,
-    Handle<FixedArray> host_defined_options) {
+    MaybeHandle<FixedArray> maybe_host_defined_options) {
   Isolate* isolate = source->GetIsolate();
   if (compile_options == ScriptCompiler::kNoCompileOptions) {
     cached_data = NULL;
@@ -1237,12 +1237,12 @@ Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
   CompilationCache* compilation_cache = isolate->compilation_cache();
 
   // Do a lookup in the compilation cache but not for extensions.
-  Handle<SharedFunctionInfo> result;
+  MaybeHandle<SharedFunctionInfo> maybe_result;
   Handle<Cell> vector;
   if (extension == NULL) {
     // First check per-isolate compilation cache.
     InfoVectorPair pair = compilation_cache->LookupScript(
-        source, script_name, line_offset, column_offset, resource_options,
+        source, maybe_script_name, line_offset, column_offset, resource_options,
         context, language_mode);
     if (!pair.has_shared() &&
         compile_options == ScriptCompiler::kConsumeCodeCache &&
@@ -1270,7 +1270,7 @@ Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
       // Deserializer failed. Fall through to compile.
     } else {
       if (pair.has_shared()) {
-        result = Handle<SharedFunctionInfo>(pair.shared(), isolate);
+        maybe_result = MaybeHandle<SharedFunctionInfo>(pair.shared(), isolate);
       }
       if (pair.has_vector()) {
         vector = Handle<Cell>(pair.vector(), isolate);
@@ -1283,7 +1283,7 @@ Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
     timer.Start();
   }
 
-  if (result.is_null() || ShouldProduceCodeCache(compile_options)) {
+  if (maybe_result.is_null() || ShouldProduceCodeCache(compile_options)) {
     // No cache entry found, or embedder wants a code cache. Compile the script.
 
     // Create a script object describing the script to be compiled.
@@ -1298,16 +1298,19 @@ Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
     } else if (natives == INSPECTOR_CODE) {
       script->set_type(Script::TYPE_INSPECTOR);
     }
-    if (!script_name.is_null()) {
+    Handle<Object> script_name;
+    if (maybe_script_name.ToHandle(&script_name)) {
       script->set_name(*script_name);
       script->set_line_offset(line_offset);
       script->set_column_offset(column_offset);
     }
     script->set_origin_options(resource_options);
-    if (!source_map_url.is_null()) {
+    Handle<Object> source_map_url;
+    if (maybe_source_map_url.ToHandle(&source_map_url)) {
       script->set_source_mapping_url(*source_map_url);
     }
-    if (!host_defined_options.is_null()) {
+    Handle<FixedArray> host_defined_options;
+    if (maybe_host_defined_options.ToHandle(&host_defined_options)) {
       script->set_host_defined_options(*host_defined_options);
     }
 
@@ -1331,8 +1334,9 @@ Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
 
     parse_info.set_language_mode(
         static_cast<LanguageMode>(parse_info.language_mode() | language_mode));
-    CompileToplevel(&parse_info, isolate).ToHandle(&result);
-    if (extension == NULL && !result.is_null()) {
+    maybe_result = CompileToplevel(&parse_info, isolate);
+    Handle<SharedFunctionInfo> result;
+    if (extension == NULL && maybe_result.ToHandle(&result)) {
       // We need a feedback vector.
       DCHECK(result->is_compiled());
       Handle<FeedbackVector> feedback_vector =
@@ -1356,7 +1360,7 @@ Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
       }
     }
 
-    if (result.is_null()) {
+    if (maybe_result.is_null()) {
       if (natives != EXTENSION_CODE && natives != NATIVES_CODE) {
         isolate->ReportPendingMessages();
       }
@@ -1364,7 +1368,7 @@ Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
       isolate->debug()->OnAfterCompile(script);
     }
   }
-  return result;
+  return maybe_result;
 }
 
 Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForStreamedScript(

src/compiler.h

@@ -107,13 +107,14 @@ class V8_EXPORT_PRIVATE Compiler : public AllStatic {
       ParseRestriction restriction, int parameters_end_pos);
 
   // Create a shared function info object for a String source within a context.
-  static Handle<SharedFunctionInfo> GetSharedFunctionInfoForScript(
-      Handle<String> source, Handle<Object> script_name, int line_offset,
-      int column_offset, ScriptOriginOptions resource_options,
-      Handle<Object> source_map_url, Handle<Context> context,
+  static MaybeHandle<SharedFunctionInfo> GetSharedFunctionInfoForScript(
+      Handle<String> source, MaybeHandle<Object> maybe_script_name,
+      int line_offset, int column_offset, ScriptOriginOptions resource_options,
+      MaybeHandle<Object> maybe_source_map_url, Handle<Context> context,
       v8::Extension* extension, ScriptData** cached_data,
       ScriptCompiler::CompileOptions compile_options,
-      NativesFlag is_natives_code, Handle<FixedArray> host_defined_options);
+      NativesFlag is_natives_code,
+      MaybeHandle<FixedArray> maybe_host_defined_options);
 
   // Create a shared function info object for a Script that has already been
   // parsed while the script was being loaded from a streamed source.

test/cctest/compiler/test-linkage.cc

@@ -33,11 +33,13 @@ static Handle<JSFunction> Compile(const char* source) {
   Handle<String> source_code = isolate->factory()
                                    ->NewStringFromUtf8(CStrVector(source))
                                    .ToHandleChecked();
-  Handle<SharedFunctionInfo> shared = Compiler::GetSharedFunctionInfoForScript(
-      source_code, Handle<String>(), 0, 0, v8::ScriptOriginOptions(),
-      Handle<Object>(), Handle<Context>(isolate->native_context()), NULL, NULL,
-      v8::ScriptCompiler::kNoCompileOptions, NOT_NATIVES_CODE,
-      Handle<FixedArray>());
+  Handle<SharedFunctionInfo> shared =
+      Compiler::GetSharedFunctionInfoForScript(
+          source_code, MaybeHandle<String>(), 0, 0, v8::ScriptOriginOptions(),
+          MaybeHandle<Object>(), Handle<Context>(isolate->native_context()),
+          NULL, NULL, v8::ScriptCompiler::kNoCompileOptions, NOT_NATIVES_CODE,
+          MaybeHandle<FixedArray>())
+          .ToHandleChecked();
   return isolate->factory()->NewFunctionFromSharedFunctionInfo(
       shared, isolate->native_context());
 }

test/cctest/test-compiler.cc

@@ -63,11 +63,13 @@ static Handle<JSFunction> Compile(const char* source) {
   Isolate* isolate = CcTest::i_isolate();
   Handle<String> source_code = isolate->factory()->NewStringFromUtf8(
       CStrVector(source)).ToHandleChecked();
-  Handle<SharedFunctionInfo> shared = Compiler::GetSharedFunctionInfoForScript(
-      source_code, Handle<String>(), 0, 0, v8::ScriptOriginOptions(),
-      Handle<Object>(), Handle<Context>(isolate->native_context()), NULL, NULL,
-      v8::ScriptCompiler::kNoCompileOptions, NOT_NATIVES_CODE,
-      Handle<FixedArray>());
+  Handle<SharedFunctionInfo> shared =
+      Compiler::GetSharedFunctionInfoForScript(
+          source_code, MaybeHandle<String>(), 0, 0, v8::ScriptOriginOptions(),
+          MaybeHandle<Object>(), Handle<Context>(isolate->native_context()),
+          NULL, NULL, v8::ScriptCompiler::kNoCompileOptions, NOT_NATIVES_CODE,
+          MaybeHandle<FixedArray>())
+          .ToHandleChecked();
   return isolate->factory()->NewFunctionFromSharedFunctionInfo(
       shared, isolate->native_context());
 }

test/cctest/test-serialize.cc

@@ -1200,9 +1200,10 @@ static Handle<SharedFunctionInfo> CompileScript(
     Isolate* isolate, Handle<String> source, Handle<String> name,
     ScriptData** cached_data, v8::ScriptCompiler::CompileOptions options) {
   return Compiler::GetSharedFunctionInfoForScript(
-      source, name, 0, 0, v8::ScriptOriginOptions(), Handle<Object>(),
-      Handle<Context>(isolate->native_context()), NULL, cached_data, options,
-      NOT_NATIVES_CODE, Handle<FixedArray>());
+             source, name, 0, 0, v8::ScriptOriginOptions(), Handle<Object>(),
+             Handle<Context>(isolate->native_context()), NULL, cached_data,
+             options, NOT_NATIVES_CODE, Handle<FixedArray>())
+      .ToHandleChecked();
 }
 
 TEST(CodeSerializerOnePlusOne) {
@@ -2089,11 +2090,13 @@ TEST(Regress503552) {
   Handle<String> source = isolate->factory()->NewStringFromAsciiChecked(
       "function f() {} function g() {}");
   ScriptData* script_data = NULL;
-  Handle<SharedFunctionInfo> shared = Compiler::GetSharedFunctionInfoForScript(
-      source, Handle<String>(), 0, 0, v8::ScriptOriginOptions(),
-      Handle<Object>(), Handle<Context>(isolate->native_context()), NULL,
-      &script_data, v8::ScriptCompiler::kProduceCodeCache, NOT_NATIVES_CODE,
-      Handle<FixedArray>());
+  Handle<SharedFunctionInfo> shared =
+      Compiler::GetSharedFunctionInfoForScript(
+          source, MaybeHandle<String>(), 0, 0, v8::ScriptOriginOptions(),
+          MaybeHandle<Object>(), Handle<Context>(isolate->native_context()),
+          NULL, &script_data, v8::ScriptCompiler::kProduceCodeCache,
+          NOT_NATIVES_CODE, MaybeHandle<FixedArray>())
+          .ToHandleChecked();
   delete script_data;
 
   heap::SimulateIncrementalMarking(isolate->heap());