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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "js/OffThreadScriptCompilation.h"
#include "mozilla/Assertions.h" // MOZ_ASSERT
#include "mozilla/Range.h" // mozilla::Range
#include "mozilla/Utf8.h" // mozilla::Utf8Unit
#include "mozilla/Vector.h" // mozilla::Vector
#include <stddef.h> // size_t
#include "jspubtd.h" // js::CurrentThreadCanAccessRuntime
#include "jstypes.h" // JS_PUBLIC_API
#include "js/CompileOptions.h" // JS::ReadOnlyCompileOptions
#include "js/SourceText.h" // JS::SourceText
#include "vm/HelperThreadState.h" // js::OffThreadParsingMustWaitForGC, js::StartOffThreadParseScript
#include "vm/JSContext.h" // JSContext
#include "vm/Runtime.h" // js::CanUseExtraThreads
using namespace js;
using mozilla::Utf8Unit;
using JS::ReadOnlyCompileOptions;
enum class OffThread { Compile, Decode };
static bool CanDoOffThread(JSContext* cx, const ReadOnlyCompileOptions& options,
size_t length, OffThread what) {
static const size_t TINY_LENGTH = 5 * 1000;
static const size_t HUGE_SRC_LENGTH = 100 * 1000;
static const size_t HUGE_BC_LENGTH = 367 * 1000;
// These are heuristics which the caller may choose to ignore (e.g., for
// testing purposes).
if (!options.forceAsync) {
// Compiling off the main thread inolves creating a new Zone and other
// significant overheads. Don't bother if the script is tiny.
if (length < TINY_LENGTH) {
return false;
}
// If the parsing task would have to wait for GC to complete, it'll probably
// be faster to just start it synchronously on the main thread unless the
// script is huge.
//
// NOTE: JS::DecodeMultiOffThreadScript does not use this API so we don't
// have to worry about it still using off-thread parse global.
bool mustWait = options.useOffThreadParseGlobal &&
OffThreadParsingMustWaitForGC(cx->runtime());
if (mustWait) {
if (what == OffThread::Compile && length < HUGE_SRC_LENGTH) {
return false;
}
if (what == OffThread::Decode && length < HUGE_BC_LENGTH) {
return false;
}
}
}
return cx->runtime()->canUseParallelParsing() && CanUseExtraThreads();
}
JS_PUBLIC_API bool JS::CanCompileOffThread(
JSContext* cx, const ReadOnlyCompileOptions& options, size_t length) {
return CanDoOffThread(cx, options, length, OffThread::Compile);
}
JS_PUBLIC_API JS::OffThreadToken* JS::CompileOffThread(
JSContext* cx, const ReadOnlyCompileOptions& options,
JS::SourceText<char16_t>& srcBuf, OffThreadCompileCallback callback,
void* callbackData) {
MOZ_ASSERT(CanCompileOffThread(cx, options, srcBuf.length()));
return StartOffThreadParseScript(cx, options, srcBuf, callback, callbackData);
}
JS_PUBLIC_API JS::OffThreadToken* JS::CompileOffThread(
JSContext* cx, const ReadOnlyCompileOptions& options,
JS::SourceText<Utf8Unit>& srcBuf, OffThreadCompileCallback callback,
void* callbackData) {
MOZ_ASSERT(CanCompileOffThread(cx, options, srcBuf.length()));
return StartOffThreadParseScript(cx, options, srcBuf, callback, callbackData);
}
JS_PUBLIC_API JSScript* JS::FinishOffThreadScript(JSContext* cx,
JS::OffThreadToken* token) {
MOZ_ASSERT(cx);
MOZ_ASSERT(CurrentThreadCanAccessRuntime(cx->runtime()));
return HelperThreadState().finishScriptParseTask(cx, token);
}
JS_PUBLIC_API JSScript* JS::FinishOffThreadScriptAndStartIncrementalEncoding(
JSContext* cx, JS::OffThreadToken* token) {
MOZ_ASSERT(cx);
MOZ_ASSERT(CurrentThreadCanAccessRuntime(cx->runtime()));
return HelperThreadState().finishScriptParseTask(cx, token,
StartEncoding::Yes);
}
JS_PUBLIC_API void JS::CancelOffThreadScript(JSContext* cx,
JS::OffThreadToken* token) {
MOZ_ASSERT(cx);
MOZ_ASSERT(CurrentThreadCanAccessRuntime(cx->runtime()));
HelperThreadState().cancelParseTask(cx->runtime(), ParseTaskKind::Script,
token);
}
JS_PUBLIC_API JS::OffThreadToken* JS::CompileOffThreadModule(
JSContext* cx, const ReadOnlyCompileOptions& options,
JS::SourceText<char16_t>& srcBuf, OffThreadCompileCallback callback,
void* callbackData) {
MOZ_ASSERT(CanCompileOffThread(cx, options, srcBuf.length()));
return StartOffThreadParseModule(cx, options, srcBuf, callback, callbackData);
}
JS_PUBLIC_API JS::OffThreadToken* JS::CompileOffThreadModule(
JSContext* cx, const ReadOnlyCompileOptions& options,
JS::SourceText<Utf8Unit>& srcBuf, OffThreadCompileCallback callback,
void* callbackData) {
MOZ_ASSERT(CanCompileOffThread(cx, options, srcBuf.length()));
return StartOffThreadParseModule(cx, options, srcBuf, callback, callbackData);
}
JS_PUBLIC_API JSObject* JS::FinishOffThreadModule(JSContext* cx,
JS::OffThreadToken* token) {
MOZ_ASSERT(cx);
MOZ_ASSERT(CurrentThreadCanAccessRuntime(cx->runtime()));
return HelperThreadState().finishModuleParseTask(cx, token);
}
JS_PUBLIC_API void JS::CancelOffThreadModule(JSContext* cx,
JS::OffThreadToken* token) {
MOZ_ASSERT(cx);
MOZ_ASSERT(CurrentThreadCanAccessRuntime(cx->runtime()));
HelperThreadState().cancelParseTask(cx->runtime(), ParseTaskKind::Module,
token);
}
JS_PUBLIC_API bool JS::CanDecodeOffThread(JSContext* cx,
const ReadOnlyCompileOptions& options,
size_t length) {
return CanDoOffThread(cx, options, length, OffThread::Decode);
}
JS_PUBLIC_API JS::OffThreadToken* JS::DecodeOffThreadScript(
JSContext* cx, const ReadOnlyCompileOptions& options,
mozilla::Vector<uint8_t>& buffer /* TranscodeBuffer& */, size_t cursor,
OffThreadCompileCallback callback, void* callbackData) {
JS::TranscodeRange range(buffer.begin() + cursor, buffer.length() - cursor);
MOZ_ASSERT(CanDecodeOffThread(cx, options, range.length()));
return StartOffThreadDecodeScript(cx, options, range, callback, callbackData);
}
JS_PUBLIC_API JS::OffThreadToken* JS::DecodeOffThreadScript(
JSContext* cx, const ReadOnlyCompileOptions& options,
const mozilla::Range<uint8_t>& range /* TranscodeRange& */,
OffThreadCompileCallback callback, void* callbackData) {
MOZ_ASSERT(CanDecodeOffThread(cx, options, range.length()));
return StartOffThreadDecodeScript(cx, options, range, callback, callbackData);
}
JS_PUBLIC_API JSScript* JS::FinishOffThreadScriptDecoder(
JSContext* cx, JS::OffThreadToken* token) {
MOZ_ASSERT(cx);
MOZ_ASSERT(CurrentThreadCanAccessRuntime(cx->runtime()));
return HelperThreadState().finishScriptDecodeTask(cx, token);
}
JS_PUBLIC_API void JS::CancelOffThreadScriptDecoder(JSContext* cx,
JS::OffThreadToken* token) {
MOZ_ASSERT(cx);
MOZ_ASSERT(CurrentThreadCanAccessRuntime(cx->runtime()));
HelperThreadState().cancelParseTask(cx->runtime(),
ParseTaskKind::ScriptDecode, token);
}
JS_PUBLIC_API JS::OffThreadToken* JS::DecodeMultiOffThreadScripts(
JSContext* cx, const ReadOnlyCompileOptions& options,
TranscodeSources& sources, OffThreadCompileCallback callback,
void* callbackData) {
#ifdef DEBUG
size_t length = 0;
for (auto& source : sources) {
length += source.range.length();
}
MOZ_ASSERT(CanCompileOffThread(cx, options, length));
#endif
return StartOffThreadDecodeMultiScripts(cx, options, sources, callback,
callbackData);
}
JS_PUBLIC_API bool JS::FinishMultiOffThreadScriptsDecoder(
JSContext* cx, JS::OffThreadToken* token,
MutableHandle<ScriptVector> scripts) {
MOZ_ASSERT(cx);
MOZ_ASSERT(CurrentThreadCanAccessRuntime(cx->runtime()));
return HelperThreadState().finishMultiScriptsDecodeTask(cx, token, scripts);
}
JS_PUBLIC_API void JS::CancelMultiOffThreadScriptsDecoder(
JSContext* cx, JS::OffThreadToken* token) {
MOZ_ASSERT(cx);
MOZ_ASSERT(CurrentThreadCanAccessRuntime(cx->runtime()));
HelperThreadState().cancelParseTask(cx->runtime(),
ParseTaskKind::MultiScriptsDecode, token);
}
namespace js {
bool gUseOffThreadParseGlobal = false;
} // namespace js
JS_PUBLIC_API void JS::SetUseOffThreadParseGlobal(bool value) {
gUseOffThreadParseGlobal = value;
}
bool js::UseOffThreadParseGlobal() { return gUseOffThreadParseGlobal; }