| /* |
| * Copyright (C) 2013-2019 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| #include "DFGLazyJSValue.h" |
| |
| #if ENABLE(DFG_JIT) |
| |
| #include "CCallHelpers.h" |
| #include "DFGGraph.h" |
| #include "JSCJSValueInlines.h" |
| #include "LinkBuffer.h" |
| |
| namespace JSC { namespace DFG { |
| |
| LazyJSValue LazyJSValue::newString(Graph& graph, const String& string) |
| { |
| LazyJSValue result; |
| result.m_kind = NewStringImpl; |
| result.u.stringImpl = graph.m_localStrings.add(string).iterator->impl(); |
| return result; |
| } |
| |
| JSValue LazyJSValue::getValue(VM& vm) const |
| { |
| switch (m_kind) { |
| case KnownValue: |
| return value()->value(); |
| case SingleCharacterString: |
| return jsSingleCharacterString(vm, u.character); |
| case KnownStringImpl: |
| return jsString(vm, u.stringImpl); |
| case NewStringImpl: |
| return jsString(vm, AtomStringImpl::add(u.stringImpl)); |
| } |
| RELEASE_ASSERT_NOT_REACHED(); |
| return JSValue(); |
| } |
| |
| static TriState equalToSingleCharacter(JSValue value, UChar character) |
| { |
| if (!value.isString()) |
| return TriState::False; |
| |
| JSString* jsString = asString(value); |
| if (jsString->length() != 1) |
| return TriState::False; |
| |
| const StringImpl* string = jsString->tryGetValueImpl(); |
| if (!string) |
| return TriState::Indeterminate; |
| |
| return triState(string->at(0) == character); |
| } |
| |
| static TriState equalToStringImpl(JSValue value, StringImpl* stringImpl) |
| { |
| if (!value.isString()) |
| return TriState::False; |
| |
| JSString* jsString = asString(value); |
| const StringImpl* string = jsString->tryGetValueImpl(); |
| if (!string) |
| return TriState::Indeterminate; |
| |
| return triState(WTF::equal(stringImpl, string)); |
| } |
| |
| const StringImpl* LazyJSValue::tryGetStringImpl(VM& vm) const |
| { |
| switch (m_kind) { |
| case KnownStringImpl: |
| case NewStringImpl: |
| return u.stringImpl; |
| |
| case KnownValue: |
| if (JSString* string = value()->dynamicCast<JSString*>(vm)) |
| return string->tryGetValueImpl(); |
| return nullptr; |
| |
| case SingleCharacterString: |
| return nullptr; |
| } |
| RELEASE_ASSERT_NOT_REACHED(); |
| return nullptr; |
| } |
| |
| String LazyJSValue::tryGetString(Graph& graph) const |
| { |
| switch (m_kind) { |
| case NewStringImpl: |
| return u.stringImpl; |
| |
| case SingleCharacterString: |
| return String(&u.character, 1); |
| |
| case KnownValue: |
| case KnownStringImpl: |
| if (const StringImpl* string = tryGetStringImpl(graph.m_vm)) { |
| unsigned ginormousStringLength = 10000; |
| if (string->length() > ginormousStringLength) |
| return String(); |
| |
| auto result = graph.m_copiedStrings.add(string, String()); |
| if (result.isNewEntry) |
| result.iterator->value = string->isolatedCopy(); |
| return result.iterator->value; |
| } |
| |
| return String(); |
| } |
| RELEASE_ASSERT_NOT_REACHED(); |
| return String(); |
| } |
| |
| TriState LazyJSValue::strictEqual(const LazyJSValue& other) const |
| { |
| switch (m_kind) { |
| case KnownValue: |
| switch (other.m_kind) { |
| case KnownValue: { |
| if (!value()->value() || !other.value()->value()) |
| return value()->value() == other.value()->value() ? TriState::True : TriState::False; |
| return JSValue::pureStrictEqual(value()->value(), other.value()->value()); |
| } |
| case SingleCharacterString: { |
| if (!value()->value()) |
| return TriState::False; |
| return equalToSingleCharacter(value()->value(), other.character()); |
| } |
| case KnownStringImpl: |
| case NewStringImpl: { |
| if (!value()->value()) |
| return TriState::False; |
| return equalToStringImpl(value()->value(), other.stringImpl()); |
| } |
| } |
| break; |
| case SingleCharacterString: |
| switch (other.m_kind) { |
| case SingleCharacterString: |
| return triState(character() == other.character()); |
| case KnownStringImpl: |
| case NewStringImpl: |
| if (other.stringImpl()->length() != 1) |
| return TriState::False; |
| return triState(other.stringImpl()->at(0) == character()); |
| case KnownValue: |
| return other.strictEqual(*this); |
| } |
| break; |
| case KnownStringImpl: |
| case NewStringImpl: |
| switch (other.m_kind) { |
| case KnownStringImpl: |
| case NewStringImpl: |
| return triState(WTF::equal(stringImpl(), other.stringImpl())); |
| case SingleCharacterString: |
| case KnownValue: |
| return other.strictEqual(*this); |
| } |
| break; |
| } |
| RELEASE_ASSERT_NOT_REACHED(); |
| return TriState::False; |
| } |
| |
| uintptr_t LazyJSValue::switchLookupValue(SwitchKind kind) const |
| { |
| // NB. Not every kind of JSValue will be able to give you a switch lookup |
| // value, and this method will assert, or do bad things, if you use it |
| // for a kind of value that can't. |
| switch (m_kind) { |
| case KnownValue: |
| switch (kind) { |
| case SwitchImm: |
| if (value()->value()) |
| return value()->value().asInt32(); |
| return 0; |
| case SwitchCell: |
| if (value()->value()) |
| return bitwise_cast<uintptr_t>(value()->value().asCell()); |
| return 0; |
| default: |
| RELEASE_ASSERT_NOT_REACHED(); |
| return 0; |
| } |
| case SingleCharacterString: |
| switch (kind) { |
| case SwitchChar: |
| return character(); |
| default: |
| RELEASE_ASSERT_NOT_REACHED(); |
| return 0; |
| } |
| case KnownStringImpl: |
| case NewStringImpl: |
| RELEASE_ASSERT_NOT_REACHED(); |
| return 0; |
| } |
| RELEASE_ASSERT_NOT_REACHED(); |
| return 0; |
| } |
| |
| void LazyJSValue::emit(CCallHelpers& jit, JSValueRegs result) const |
| { |
| if (m_kind == KnownValue) { |
| jit.moveValue(value()->value(), result); |
| return; |
| } |
| |
| // It must be some kind of cell. |
| #if USE(JSVALUE32_64) |
| jit.move(CCallHelpers::TrustedImm32(JSValue::CellTag), result.tagGPR()); |
| #endif |
| CCallHelpers::DataLabelPtr label = jit.moveWithPatch( |
| CCallHelpers::TrustedImmPtr(static_cast<size_t>(0xd1e7beeflu)), |
| result.payloadGPR()); |
| |
| LazyJSValue thisValue = *this; |
| |
| // Once we do this, we're committed. Otherwise we leak memory. Note that we call ref/deref |
| // manually to ensure that there is no concurrency shadiness. We are doing something here |
| // that might be rather brutal: transfering ownership of this string. |
| if (m_kind == NewStringImpl) |
| thisValue.u.stringImpl->ref(); |
| |
| CodeBlock* codeBlock = jit.codeBlock(); |
| |
| jit.addLinkTask( |
| [codeBlock, label, thisValue] (LinkBuffer& linkBuffer) { |
| JSValue realValue = thisValue.getValue(codeBlock->vm()); |
| RELEASE_ASSERT(realValue.isCell()); |
| |
| codeBlock->addConstant(ConcurrentJSLocker(codeBlock->m_lock), realValue); |
| |
| if (thisValue.m_kind == NewStringImpl) |
| thisValue.u.stringImpl->deref(); |
| |
| linkBuffer.patch(label, realValue.asCell()); |
| }); |
| } |
| |
| void LazyJSValue::dumpInContext(PrintStream& out, DumpContext* context) const |
| { |
| switch (m_kind) { |
| case KnownValue: |
| value()->dumpInContext(out, context); |
| return; |
| case SingleCharacterString: |
| out.print("Lazy:SingleCharacterString("); |
| out.printf("%04X", static_cast<unsigned>(character())); |
| out.print(" / ", StringImpl::utf8ForCharacters(&u.character, 1).value(), ")"); |
| return; |
| case KnownStringImpl: |
| out.print("Lazy:KnownString(", stringImpl(), ")"); |
| return; |
| case NewStringImpl: |
| out.print("Lazy:NewString(", stringImpl(), ")"); |
| return; |
| } |
| RELEASE_ASSERT_NOT_REACHED(); |
| } |
| |
| void LazyJSValue::dump(PrintStream& out) const |
| { |
| dumpInContext(out, nullptr); |
| } |
| |
| } } // namespace JSC::DFG |
| |
| #endif // ENABLE(DFG_JIT) |
| |
