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-rw-r--r--JavaScriptCore/runtime/JSString.h270
1 files changed, 116 insertions, 154 deletions
diff --git a/JavaScriptCore/runtime/JSString.h b/JavaScriptCore/runtime/JSString.h
index cff8e3a..85d3c8e 100644
--- a/JavaScriptCore/runtime/JSString.h
+++ b/JavaScriptCore/runtime/JSString.h
@@ -29,6 +29,7 @@
#include "JSNumberCell.h"
#include "PropertyDescriptor.h"
#include "PropertySlot.h"
+#include "RopeImpl.h"
namespace JSC {
@@ -41,7 +42,6 @@ namespace JSC {
JSString* jsSingleCharacterString(JSGlobalData*, UChar);
JSString* jsSingleCharacterString(ExecState*, UChar);
- JSString* jsSingleCharacterSubstring(JSGlobalData*, const UString&, unsigned offset);
JSString* jsSingleCharacterSubstring(ExecState*, const UString&, unsigned offset);
JSString* jsSubstring(JSGlobalData*, const UString&, unsigned offset, unsigned length);
JSString* jsSubstring(ExecState*, const UString&, unsigned offset, unsigned length);
@@ -66,183 +66,132 @@ namespace JSC {
public:
friend class JIT;
friend class JSGlobalData;
+ friend class SpecializedThunkJIT;
+ friend struct ThunkHelpers;
- // A Rope is a string composed of a set of substrings.
- class Rope : public RefCounted<Rope> {
+ class RopeBuilder {
public:
- // A Rope is composed from a set of smaller strings called Fibers.
- // Each Fiber in a rope is either UString::Rep or another Rope.
- class Fiber {
- public:
- Fiber() : m_value(0) {}
- Fiber(UString::Rep* string) : m_value(reinterpret_cast<intptr_t>(string)) {}
- Fiber(Rope* rope) : m_value(reinterpret_cast<intptr_t>(rope) | 1) {}
-
- Fiber(void* nonFiber) : m_value(reinterpret_cast<intptr_t>(nonFiber)) {}
-
- void deref()
- {
- if (isRope())
- rope()->deref();
- else
- string()->deref();
- }
-
- Fiber& ref()
- {
- if (isString())
- string()->ref();
- else
- rope()->ref();
- return *this;
- }
-
- unsigned refAndGetLength()
- {
- if (isString()) {
- UString::Rep* rep = string();
- return rep->ref()->size();
- } else {
- Rope* r = rope();
- r->ref();
- return r->stringLength();
- }
- }
-
- bool isRope() { return m_value & 1; }
- Rope* rope() { return reinterpret_cast<Rope*>(m_value & ~1); }
- bool isString() { return !isRope(); }
- UString::Rep* string() { return reinterpret_cast<UString::Rep*>(m_value); }
-
- void* nonFiber() { return reinterpret_cast<void*>(m_value); }
- private:
- intptr_t m_value;
- };
-
- // Creates a Rope comprising of 'ropeLength' Fibers.
- // The Rope is constructed in an uninitialized state - initialize must be called for each Fiber in the Rope.
- static PassRefPtr<Rope> createOrNull(unsigned ropeLength)
+ RopeBuilder(unsigned fiberCount)
+ : m_index(0)
+ , m_rope(RopeImpl::tryCreateUninitialized(fiberCount))
{
- void* allocation;
- if (tryFastMalloc(sizeof(Rope) + (ropeLength - 1) * sizeof(Fiber)).getValue(allocation))
- return adoptRef(new (allocation) Rope(ropeLength));
- return 0;
}
- ~Rope();
- void destructNonRecursive();
+ bool isOutOfMemory() { return !m_rope; }
- void append(unsigned &index, Fiber& fiber)
+ void append(RopeImpl::Fiber& fiber)
{
- m_fibers[index++] = fiber;
- m_stringLength += fiber.refAndGetLength();
+ ASSERT(m_rope);
+ m_rope->initializeFiber(m_index, fiber);
}
- void append(unsigned &index, const UString& string)
+ void append(const UString& string)
{
- UString::Rep* rep = string.rep();
- m_fibers[index++] = Fiber(rep);
- m_stringLength += rep->ref()->size();
+ ASSERT(m_rope);
+ m_rope->initializeFiber(m_index, string.rep());
}
- void append(unsigned& index, JSString* jsString)
+ void append(JSString* jsString)
{
if (jsString->isRope()) {
- for (unsigned i = 0; i < jsString->m_ropeLength; ++i)
- append(index, jsString->m_fibers[i]);
+ for (unsigned i = 0; i < jsString->m_fiberCount; ++i)
+ append(jsString->m_other.m_fibers[i]);
} else
- append(index, jsString->string());
+ append(jsString->string());
}
- unsigned ropeLength() { return m_ropeLength; }
- unsigned stringLength() { return m_stringLength; }
- Fiber& fibers(unsigned index) { return m_fibers[index]; }
+ PassRefPtr<RopeImpl> release()
+ {
+ ASSERT(m_index == m_rope->fiberCount());
+ return m_rope.release();
+ }
+
+ unsigned length() { return m_rope->length(); }
private:
- Rope(unsigned ropeLength) : m_ropeLength(ropeLength), m_stringLength(0) {}
- void* operator new(size_t, void* inPlace) { return inPlace; }
-
- unsigned m_ropeLength;
- unsigned m_stringLength;
- Fiber m_fibers[1];
+ unsigned m_index;
+ RefPtr<RopeImpl> m_rope;
};
ALWAYS_INLINE JSString(JSGlobalData* globalData, const UString& value)
: JSCell(globalData->stringStructure.get())
- , m_stringLength(value.size())
+ , m_length(value.size())
, m_value(value)
- , m_ropeLength(0)
+ , m_fiberCount(0)
{
+ ASSERT(!m_value.isNull());
Heap::heap(this)->reportExtraMemoryCost(value.cost());
}
enum HasOtherOwnerType { HasOtherOwner };
JSString(JSGlobalData* globalData, const UString& value, HasOtherOwnerType)
: JSCell(globalData->stringStructure.get())
- , m_stringLength(value.size())
+ , m_length(value.size())
, m_value(value)
- , m_ropeLength(0)
+ , m_fiberCount(0)
{
+ ASSERT(!m_value.isNull());
}
JSString(JSGlobalData* globalData, PassRefPtr<UString::Rep> value, HasOtherOwnerType)
: JSCell(globalData->stringStructure.get())
- , m_stringLength(value->size())
+ , m_length(value->length())
, m_value(value)
- , m_ropeLength(0)
+ , m_fiberCount(0)
{
+ ASSERT(!m_value.isNull());
}
- JSString(JSGlobalData* globalData, PassRefPtr<JSString::Rope> rope)
+ JSString(JSGlobalData* globalData, PassRefPtr<RopeImpl> rope)
: JSCell(globalData->stringStructure.get())
- , m_stringLength(rope->stringLength())
- , m_ropeLength(1)
+ , m_length(rope->length())
+ , m_fiberCount(1)
{
- m_fibers[0] = rope.releaseRef();
+ m_other.m_fibers[0] = rope.releaseRef();
}
// This constructor constructs a new string by concatenating s1 & s2.
- // This should only be called with ropeLength <= 3.
- JSString(JSGlobalData* globalData, unsigned ropeLength, JSString* s1, JSString* s2)
+ // This should only be called with fiberCount <= 3.
+ JSString(JSGlobalData* globalData, unsigned fiberCount, JSString* s1, JSString* s2)
: JSCell(globalData->stringStructure.get())
- , m_stringLength(s1->length() + s2->length())
- , m_ropeLength(ropeLength)
+ , m_length(s1->length() + s2->length())
+ , m_fiberCount(fiberCount)
{
- ASSERT(ropeLength <= s_maxInternalRopeLength);
+ ASSERT(fiberCount <= s_maxInternalRopeLength);
unsigned index = 0;
appendStringInConstruct(index, s1);
appendStringInConstruct(index, s2);
- ASSERT(ropeLength == index);
+ ASSERT(fiberCount == index);
}
// This constructor constructs a new string by concatenating s1 & s2.
- // This should only be called with ropeLength <= 3.
- JSString(JSGlobalData* globalData, unsigned ropeLength, JSString* s1, const UString& u2)
+ // This should only be called with fiberCount <= 3.
+ JSString(JSGlobalData* globalData, unsigned fiberCount, JSString* s1, const UString& u2)
: JSCell(globalData->stringStructure.get())
- , m_stringLength(s1->length() + u2.size())
- , m_ropeLength(ropeLength)
+ , m_length(s1->length() + u2.size())
+ , m_fiberCount(fiberCount)
{
- ASSERT(ropeLength <= s_maxInternalRopeLength);
+ ASSERT(fiberCount <= s_maxInternalRopeLength);
unsigned index = 0;
appendStringInConstruct(index, s1);
appendStringInConstruct(index, u2);
- ASSERT(ropeLength == index);
+ ASSERT(fiberCount == index);
}
// This constructor constructs a new string by concatenating s1 & s2.
- // This should only be called with ropeLength <= 3.
- JSString(JSGlobalData* globalData, unsigned ropeLength, const UString& u1, JSString* s2)
+ // This should only be called with fiberCount <= 3.
+ JSString(JSGlobalData* globalData, unsigned fiberCount, const UString& u1, JSString* s2)
: JSCell(globalData->stringStructure.get())
- , m_stringLength(u1.size() + s2->length())
- , m_ropeLength(ropeLength)
+ , m_length(u1.size() + s2->length())
+ , m_fiberCount(fiberCount)
{
- ASSERT(ropeLength <= s_maxInternalRopeLength);
+ ASSERT(fiberCount <= s_maxInternalRopeLength);
unsigned index = 0;
appendStringInConstruct(index, u1);
appendStringInConstruct(index, s2);
- ASSERT(ropeLength == index);
+ ASSERT(fiberCount == index);
}
// This constructor constructs a new string by concatenating v1, v2 & v3.
- // This should only be called with ropeLength <= 3 ... which since every
- // value must require a ropeLength of at least one implies that the length
+ // This should only be called with fiberCount <= 3 ... which since every
+ // value must require a fiberCount of at least one implies that the length
// for each value must be exactly 1!
JSString(ExecState* exec, JSValue v1, JSValue v2, JSValue v3)
: JSCell(exec->globalData().stringStructure.get())
- , m_stringLength(0)
- , m_ropeLength(s_maxInternalRopeLength)
+ , m_length(0)
+ , m_fiberCount(s_maxInternalRopeLength)
{
unsigned index = 0;
appendValueInConstructAndIncrementLength(exec, index, v1);
@@ -253,26 +202,25 @@ namespace JSC {
JSString(JSGlobalData* globalData, const UString& value, JSStringFinalizerCallback finalizer, void* context)
: JSCell(globalData->stringStructure.get())
- , m_stringLength(value.size())
+ , m_length(value.size())
, m_value(value)
- , m_ropeLength(0)
+ , m_fiberCount(0)
{
+ ASSERT(!m_value.isNull());
// nasty hack because we can't union non-POD types
- m_fibers[0] = reinterpret_cast<void*>(reinterpret_cast<ptrdiff_t>(finalizer));
- m_fibers[1] = context;
+ m_other.m_finalizerCallback = finalizer;
+ m_other.m_finalizerContext = context;
Heap::heap(this)->reportExtraMemoryCost(value.cost());
}
~JSString()
{
ASSERT(vptr() == JSGlobalData::jsStringVPtr);
- for (unsigned i = 0; i < m_ropeLength; ++i)
- m_fibers[i].deref();
+ for (unsigned i = 0; i < m_fiberCount; ++i)
+ RopeImpl::deref(m_other.m_fibers[i]);
- if (!m_ropeLength && m_fibers[0].nonFiber()) {
- JSStringFinalizerCallback finalizer = reinterpret_cast<JSStringFinalizerCallback>(m_fibers[0].nonFiber());
- finalizer(this, m_fibers[1].nonFiber());
- }
+ if (!m_fiberCount && m_other.m_finalizerCallback)
+ m_other.m_finalizerCallback(this, m_other.m_finalizerContext);
}
const UString& value(ExecState* exec) const
@@ -288,14 +236,15 @@ namespace JSC {
ASSERT(isRope() == m_value.isNull());
return m_value;
}
- unsigned length() { return m_stringLength; }
+ unsigned length() { return m_length; }
bool getStringPropertySlot(ExecState*, const Identifier& propertyName, PropertySlot&);
bool getStringPropertySlot(ExecState*, unsigned propertyName, PropertySlot&);
bool getStringPropertyDescriptor(ExecState*, const Identifier& propertyName, PropertyDescriptor&);
- bool canGetIndex(unsigned i) { return i < m_stringLength; }
+ bool canGetIndex(unsigned i) { return i < m_length; }
JSString* getIndex(ExecState*, unsigned);
+ JSString* getIndexSlowCase(ExecState*, unsigned);
static PassRefPtr<Structure> createStructure(JSValue proto) { return Structure::create(proto, TypeInfo(StringType, OverridesGetOwnPropertySlot | NeedsThisConversion), AnonymousSlotCount); }
@@ -303,7 +252,7 @@ namespace JSC {
enum VPtrStealingHackType { VPtrStealingHack };
JSString(VPtrStealingHackType)
: JSCell(0)
- , m_ropeLength(0)
+ , m_fiberCount(0)
{
}
@@ -311,14 +260,19 @@ namespace JSC {
void appendStringInConstruct(unsigned& index, const UString& string)
{
- m_fibers[index++] = Rope::Fiber(string.rep()->ref());
+ UStringImpl* impl = string.rep();
+ impl->ref();
+ m_other.m_fibers[index++] = impl;
}
void appendStringInConstruct(unsigned& index, JSString* jsString)
{
if (jsString->isRope()) {
- for (unsigned i = 0; i < jsString->m_ropeLength; ++i)
- m_fibers[index++] = jsString->m_fibers[i].ref();
+ for (unsigned i = 0; i < jsString->m_fiberCount; ++i) {
+ RopeImpl::Fiber fiber = jsString->m_other.m_fibers[i];
+ fiber->ref();
+ m_other.m_fibers[index++] = fiber;
+ }
} else
appendStringInConstruct(index, jsString->string());
}
@@ -328,13 +282,15 @@ namespace JSC {
if (v.isString()) {
ASSERT(asCell(v)->isString());
JSString* s = static_cast<JSString*>(asCell(v));
- ASSERT(s->ropeLength() == 1);
+ ASSERT(s->fiberCount() == 1);
appendStringInConstruct(index, s);
- m_stringLength += s->length();
+ m_length += s->length();
} else {
UString u(v.toString(exec));
- m_fibers[index++] = Rope::Fiber(u.rep()->ref());
- m_stringLength += u.size();
+ UStringImpl* impl = u.rep();
+ impl->ref();
+ m_other.m_fibers[index++] = impl;
+ m_length += u.size();
}
}
@@ -346,8 +302,6 @@ namespace JSC {
virtual UString toString(ExecState*) const;
virtual JSObject* toThisObject(ExecState*) const;
- virtual UString toThisString(ExecState*) const;
- virtual JSString* toThisJSString(ExecState*);
// Actually getPropertySlot, not getOwnPropertySlot (see JSCell).
virtual bool getOwnPropertySlot(ExecState*, const Identifier& propertyName, PropertySlot&);
@@ -356,15 +310,25 @@ namespace JSC {
static const unsigned s_maxInternalRopeLength = 3;
- // A string is represented either by a UString or a Rope.
- unsigned m_stringLength;
+ // A string is represented either by a UString or a RopeImpl.
+ unsigned m_length;
mutable UString m_value;
- mutable unsigned m_ropeLength;
- mutable Rope::Fiber m_fibers[s_maxInternalRopeLength];
+ mutable unsigned m_fiberCount;
+ // This structure exists to support a temporary workaround for a GC issue.
+ struct JSStringFinalizerStruct {
+ JSStringFinalizerStruct() : m_finalizerCallback(0) {}
+ union {
+ mutable RopeImpl::Fiber m_fibers[s_maxInternalRopeLength];
+ struct {
+ JSStringFinalizerCallback m_finalizerCallback;
+ void* m_finalizerContext;
+ };
+ };
+ } m_other;
- bool isRope() const { return m_ropeLength; }
+ bool isRope() const { return m_fiberCount; }
UString& string() { ASSERT(!isRope()); return m_value; }
- unsigned ropeLength() { return m_ropeLength ? m_ropeLength : 1; }
+ unsigned fiberCount() { return m_fiberCount ? m_fiberCount : 1; }
friend JSValue jsString(ExecState* exec, JSString* s1, JSString* s2);
friend JSValue jsString(ExecState* exec, const UString& u1, JSString* s2);
@@ -404,8 +368,9 @@ namespace JSC {
return fixupVPtr(globalData, new (globalData) JSString(globalData, UString(&c, 1)));
}
- inline JSString* jsSingleCharacterSubstring(JSGlobalData* globalData, const UString& s, unsigned offset)
+ inline JSString* jsSingleCharacterSubstring(ExecState* exec, const UString& s, unsigned offset)
{
+ JSGlobalData* globalData = &exec->globalData();
ASSERT(offset < static_cast<unsigned>(s.size()));
UChar c = s.data()[offset];
if (c <= 0xFF)
@@ -430,7 +395,10 @@ namespace JSC {
inline JSString* JSString::getIndex(ExecState* exec, unsigned i)
{
ASSERT(canGetIndex(i));
- return jsSingleCharacterSubstring(&exec->globalData(), value(exec), i);
+ if (isRope())
+ return getIndexSlowCase(exec, i);
+ ASSERT(i < m_value.size());
+ return jsSingleCharacterSubstring(exec, value(exec), i);
}
inline JSString* jsString(JSGlobalData* globalData, const UString& s)
@@ -484,7 +452,6 @@ namespace JSC {
inline JSString* jsEmptyString(ExecState* exec) { return jsEmptyString(&exec->globalData()); }
inline JSString* jsString(ExecState* exec, const UString& s) { return jsString(&exec->globalData(), s); }
inline JSString* jsSingleCharacterString(ExecState* exec, UChar c) { return jsSingleCharacterString(&exec->globalData(), c); }
- inline JSString* jsSingleCharacterSubstring(ExecState* exec, const UString& s, unsigned offset) { return jsSingleCharacterSubstring(&exec->globalData(), s, offset); }
inline JSString* jsSubstring(ExecState* exec, const UString& s, unsigned offset, unsigned length) { return jsSubstring(&exec->globalData(), s, offset, length); }
inline JSString* jsNontrivialString(ExecState* exec, const UString& s) { return jsNontrivialString(&exec->globalData(), s); }
inline JSString* jsNontrivialString(ExecState* exec, const char* s) { return jsNontrivialString(&exec->globalData(), s); }
@@ -493,14 +460,14 @@ namespace JSC {
ALWAYS_INLINE bool JSString::getStringPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
{
if (propertyName == exec->propertyNames().length) {
- slot.setValue(jsNumber(exec, m_stringLength));
+ slot.setValue(jsNumber(exec, m_length));
return true;
}
bool isStrictUInt32;
unsigned i = propertyName.toStrictUInt32(&isStrictUInt32);
- if (isStrictUInt32 && i < m_stringLength) {
- slot.setValue(jsSingleCharacterSubstring(exec, value(exec), i));
+ if (isStrictUInt32 && i < m_length) {
+ slot.setValue(getIndex(exec, i));
return true;
}
@@ -509,8 +476,8 @@ namespace JSC {
ALWAYS_INLINE bool JSString::getStringPropertySlot(ExecState* exec, unsigned propertyName, PropertySlot& slot)
{
- if (propertyName < m_stringLength) {
- slot.setValue(jsSingleCharacterSubstring(exec, value(exec), propertyName));
+ if (propertyName < m_length) {
+ slot.setValue(getIndex(exec, propertyName));
return true;
}
@@ -521,11 +488,6 @@ namespace JSC {
// --- JSValue inlines ----------------------------
- inline JSString* JSValue::toThisJSString(ExecState* exec)
- {
- return isCell() ? asCell()->toThisJSString(exec) : jsString(exec, toString(exec));
- }
-
inline UString JSValue::toString(ExecState* exec) const
{
if (isString())