/* | |
* Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved. | |
* Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org) | |
* | |
* This library is free software; you can redistribute it and/or | |
* modify it under the terms of the GNU Library General Public | |
* License as published by the Free Software Foundation; either | |
* version 2 of the License, or (at your option) any later version. | |
* | |
* This library is distributed in the hope that it will be useful, | |
* but WITHOUT ANY WARRANTY; without even the implied warranty of | |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
* Library General Public License for more details. | |
* | |
* You should have received a copy of the GNU Library General Public License | |
* along with this library; see the file COPYING.LIB. If not, write to | |
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, | |
* Boston, MA 02110-1301, USA. | |
* | |
*/ | |
#ifndef JSImmediate_h | |
#define JSImmediate_h | |
#include <wtf/Platform.h> | |
#if !USE(JSVALUE32_64) | |
#include <wtf/Assertions.h> | |
#include <wtf/AlwaysInline.h> | |
#include <wtf/MathExtras.h> | |
#include <wtf/StdLibExtras.h> | |
#include "JSValue.h" | |
#include <limits> | |
#include <limits.h> | |
#include <stdarg.h> | |
#include <stdint.h> | |
#include <stdlib.h> | |
namespace JSC { | |
class ExecState; | |
class JSCell; | |
class JSFastMath; | |
class JSGlobalData; | |
class JSObject; | |
class UString; | |
#if USE(JSVALUE64) | |
inline intptr_t reinterpretDoubleToIntptr(double value) | |
{ | |
return WTF::bitwise_cast<intptr_t>(value); | |
} | |
inline double reinterpretIntptrToDouble(intptr_t value) | |
{ | |
return WTF::bitwise_cast<double>(value); | |
} | |
#endif | |
/* | |
* A JSValue* is either a pointer to a cell (a heap-allocated object) or an immediate (a type-tagged | |
* value masquerading as a pointer). The low two bits in a JSValue* are available for type tagging | |
* because allocator alignment guarantees they will be 00 in cell pointers. | |
* | |
* For example, on a 32 bit system: | |
* | |
* JSCell*: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX 00 | |
* [ high 30 bits: pointer address ] [ low 2 bits -- always 0 ] | |
* JSImmediate: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX TT | |
* [ high 30 bits: 'payload' ] [ low 2 bits -- tag ] | |
* | |
* Where the bottom two bits are non-zero they either indicate that the immediate is a 31 bit signed | |
* integer, or they mark the value as being an immediate of a type other than integer, with a secondary | |
* tag used to indicate the exact type. | |
* | |
* Where the lowest bit is set (TT is equal to 01 or 11) the high 31 bits form a 31 bit signed int value. | |
* Where TT is equal to 10 this indicates this is a type of immediate other than an integer, and the next | |
* two bits will form an extended tag. | |
* | |
* 31 bit signed int: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX X1 | |
* [ high 30 bits of the value ] [ high bit part of value ] | |
* Other: YYYYYYYYYYYYYYYYYYYYYYYYYYYY ZZ 10 | |
* [ extended 'payload' ] [ extended tag ] [ tag 'other' ] | |
* | |
* Where the first bit of the extended tag is set this flags the value as being a boolean, and the following | |
* bit would flag the value as undefined. If neither bits are set, the value is null. | |
* | |
* Other: YYYYYYYYYYYYYYYYYYYYYYYYYYYY UB 10 | |
* [ extended 'payload' ] [ undefined | bool ] [ tag 'other' ] | |
* | |
* For boolean value the lowest bit in the payload holds the value of the bool, all remaining bits are zero. | |
* For undefined or null immediates the payload is zero. | |
* | |
* Boolean: 000000000000000000000000000V 01 10 | |
* [ boolean value ] [ bool ] [ tag 'other' ] | |
* Undefined: 0000000000000000000000000000 10 10 | |
* [ zero ] [ undefined ] [ tag 'other' ] | |
* Null: 0000000000000000000000000000 00 10 | |
* [ zero ] [ zero ] [ tag 'other' ] | |
*/ | |
/* | |
* On 64-bit platforms, we support an alternative encoding form for immediates, if | |
* USE(JSVALUE64) is defined. When this format is used, double precision | |
* floating point values may also be encoded as JSImmediates. | |
* | |
* The encoding makes use of unused NaN space in the IEEE754 representation. Any value | |
* with the top 13 bits set represents a QNaN (with the sign bit set). QNaN values | |
* can encode a 51-bit payload. Hardware produced and C-library payloads typically | |
* have a payload of zero. We assume that non-zero payloads are available to encode | |
* pointer and integer values. Since any 64-bit bit pattern where the top 15 bits are | |
* all set represents a NaN with a non-zero payload, we can use this space in the NaN | |
* ranges to encode other values (however there are also other ranges of NaN space that | |
* could have been selected). This range of NaN space is represented by 64-bit numbers | |
* begining with the 16-bit hex patterns 0xFFFE and 0xFFFF - we rely on the fact that no | |
* valid double-precision numbers will begin fall in these ranges. | |
* | |
* The scheme we have implemented encodes double precision values by adding 2^48 to the | |
* 64-bit integer representation of the number. After this manipulation, no encoded | |
* double-precision value will begin with the pattern 0x0000 or 0xFFFF. | |
* | |
* The top 16-bits denote the type of the encoded JSImmediate: | |
* | |
* Pointer: 0000:PPPP:PPPP:PPPP | |
* 0001:****:****:**** | |
* Double:{ ... | |
* FFFE:****:****:**** | |
* Integer: FFFF:0000:IIII:IIII | |
* | |
* 32-bit signed integers are marked with the 16-bit tag 0xFFFF. The tag 0x0000 | |
* denotes a pointer, or another form of tagged immediate. Boolean, null and undefined | |
* values are encoded in the same manner as the default format. | |
*/ | |
class JSImmediate { | |
#ifdef QT_BUILD_SCRIPT_LIB | |
public: // QtScript needs isImmediate() and from() functions | |
#else | |
private: | |
#endif | |
friend class JIT; | |
friend class JSValue; | |
friend class JSFastMath; | |
friend JSValue jsNumber(ExecState* exec, double d); | |
friend JSValue jsNumber(ExecState*, char i); | |
friend JSValue jsNumber(ExecState*, unsigned char i); | |
friend JSValue jsNumber(ExecState*, short i); | |
friend JSValue jsNumber(ExecState*, unsigned short i); | |
friend JSValue jsNumber(ExecState* exec, int i); | |
friend JSValue jsNumber(ExecState* exec, unsigned i); | |
friend JSValue jsNumber(ExecState* exec, long i); | |
friend JSValue jsNumber(ExecState* exec, unsigned long i); | |
friend JSValue jsNumber(ExecState* exec, long long i); | |
friend JSValue jsNumber(ExecState* exec, unsigned long long i); | |
friend JSValue jsNumber(JSGlobalData* globalData, double d); | |
friend JSValue jsNumber(JSGlobalData* globalData, short i); | |
friend JSValue jsNumber(JSGlobalData* globalData, unsigned short i); | |
friend JSValue jsNumber(JSGlobalData* globalData, int i); | |
friend JSValue jsNumber(JSGlobalData* globalData, unsigned i); | |
friend JSValue jsNumber(JSGlobalData* globalData, long i); | |
friend JSValue jsNumber(JSGlobalData* globalData, unsigned long i); | |
friend JSValue jsNumber(JSGlobalData* globalData, long long i); | |
friend JSValue jsNumber(JSGlobalData* globalData, unsigned long long i); | |
#if USE(JSVALUE64) | |
// If all bits in the mask are set, this indicates an integer number, | |
// if any but not all are set this value is a double precision number. | |
static const intptr_t TagTypeNumber = 0xffff000000000000ll; | |
// This value is 2^48, used to encode doubles such that the encoded value will begin | |
// with a 16-bit pattern within the range 0x0001..0xFFFE. | |
static const intptr_t DoubleEncodeOffset = 0x1000000000000ll; | |
#else | |
static const intptr_t TagTypeNumber = 0x1; // bottom bit set indicates integer, this dominates the following bit | |
#endif | |
static const intptr_t TagBitTypeOther = 0x2; // second bit set indicates immediate other than an integer | |
static const intptr_t TagMask = TagTypeNumber | TagBitTypeOther; | |
static const intptr_t ExtendedTagMask = 0xC; // extended tag holds a further two bits | |
static const intptr_t ExtendedTagBitBool = 0x4; | |
static const intptr_t ExtendedTagBitUndefined = 0x8; | |
static const intptr_t FullTagTypeMask = TagMask | ExtendedTagMask; | |
static const intptr_t FullTagTypeBool = TagBitTypeOther | ExtendedTagBitBool; | |
static const intptr_t FullTagTypeUndefined = TagBitTypeOther | ExtendedTagBitUndefined; | |
static const intptr_t FullTagTypeNull = TagBitTypeOther; | |
#if USE(JSVALUE64) | |
static const int32_t IntegerPayloadShift = 0; | |
#else | |
static const int32_t IntegerPayloadShift = 1; | |
#endif | |
static const int32_t ExtendedPayloadShift = 4; | |
static const intptr_t ExtendedPayloadBitBoolValue = 1 << ExtendedPayloadShift; | |
static const int32_t signBit = 0x80000000; | |
static ALWAYS_INLINE bool isImmediate(JSValue v) | |
{ | |
return rawValue(v) & TagMask; | |
} | |
static ALWAYS_INLINE bool isNumber(JSValue v) | |
{ | |
return rawValue(v) & TagTypeNumber; | |
} | |
static ALWAYS_INLINE bool isIntegerNumber(JSValue v) | |
{ | |
#if USE(JSVALUE64) | |
return (rawValue(v) & TagTypeNumber) == TagTypeNumber; | |
#else | |
return isNumber(v); | |
#endif | |
} | |
#if USE(JSVALUE64) | |
static ALWAYS_INLINE bool isDouble(JSValue v) | |
{ | |
return isNumber(v) && !isIntegerNumber(v); | |
} | |
#endif | |
static ALWAYS_INLINE bool isPositiveIntegerNumber(JSValue v) | |
{ | |
// A single mask to check for the sign bit and the number tag all at once. | |
return (rawValue(v) & (signBit | TagTypeNumber)) == TagTypeNumber; | |
} | |
static ALWAYS_INLINE bool isBoolean(JSValue v) | |
{ | |
return (rawValue(v) & FullTagTypeMask) == FullTagTypeBool; | |
} | |
static ALWAYS_INLINE bool isUndefinedOrNull(JSValue v) | |
{ | |
// Undefined and null share the same value, bar the 'undefined' bit in the extended tag. | |
return (rawValue(v) & ~ExtendedTagBitUndefined) == FullTagTypeNull; | |
} | |
static JSValue from(char); | |
static JSValue from(signed char); | |
static JSValue from(unsigned char); | |
static JSValue from(short); | |
static JSValue from(unsigned short); | |
static JSValue from(int); | |
static JSValue from(unsigned); | |
static JSValue from(long); | |
static JSValue from(unsigned long); | |
static JSValue from(long long); | |
static JSValue from(unsigned long long); | |
static JSValue from(double); | |
static ALWAYS_INLINE bool isEitherImmediate(JSValue v1, JSValue v2) | |
{ | |
return (rawValue(v1) | rawValue(v2)) & TagMask; | |
} | |
static ALWAYS_INLINE bool areBothImmediate(JSValue v1, JSValue v2) | |
{ | |
return isImmediate(v1) & isImmediate(v2); | |
} | |
static ALWAYS_INLINE bool areBothImmediateIntegerNumbers(JSValue v1, JSValue v2) | |
{ | |
#if USE(JSVALUE64) | |
return (rawValue(v1) & rawValue(v2) & TagTypeNumber) == TagTypeNumber; | |
#else | |
return rawValue(v1) & rawValue(v2) & TagTypeNumber; | |
#endif | |
} | |
static double toDouble(JSValue); | |
static bool toBoolean(JSValue); | |
static bool getUInt32(JSValue, uint32_t&); | |
static bool getTruncatedInt32(JSValue, int32_t&); | |
static bool getTruncatedUInt32(JSValue, uint32_t&); | |
static int32_t getTruncatedInt32(JSValue); | |
static uint32_t getTruncatedUInt32(JSValue); | |
static JSValue trueImmediate(); | |
static JSValue falseImmediate(); | |
static JSValue undefinedImmediate(); | |
static JSValue nullImmediate(); | |
static JSValue zeroImmediate(); | |
static JSValue oneImmediate(); | |
private: | |
#if USE(JSVALUE64) | |
static const int minImmediateInt = ((-INT_MAX) - 1); | |
static const int maxImmediateInt = INT_MAX; | |
#else | |
static const int minImmediateInt = ((-INT_MAX) - 1) >> IntegerPayloadShift; | |
static const int maxImmediateInt = INT_MAX >> IntegerPayloadShift; | |
#endif | |
static const unsigned maxImmediateUInt = maxImmediateInt; | |
static ALWAYS_INLINE JSValue makeValue(intptr_t integer) | |
{ | |
return JSValue::makeImmediate(integer); | |
} | |
// With USE(JSVALUE64) we want the argument to be zero extended, so the | |
// integer doesn't interfere with the tag bits in the upper word. In the default encoding, | |
// if intptr_t id larger then int32_t we sign extend the value through the upper word. | |
#if USE(JSVALUE64) | |
static ALWAYS_INLINE JSValue makeInt(uint32_t value) | |
#else | |
static ALWAYS_INLINE JSValue makeInt(int32_t value) | |
#endif | |
{ | |
return makeValue((static_cast<intptr_t>(value) << IntegerPayloadShift) | TagTypeNumber); | |
} | |
#if USE(JSVALUE64) | |
static ALWAYS_INLINE JSValue makeDouble(double value) | |
{ | |
return makeValue(reinterpretDoubleToIntptr(value) + DoubleEncodeOffset); | |
} | |
#endif | |
static ALWAYS_INLINE JSValue makeBool(bool b) | |
{ | |
return makeValue((static_cast<intptr_t>(b) << ExtendedPayloadShift) | FullTagTypeBool); | |
} | |
static ALWAYS_INLINE JSValue makeUndefined() | |
{ | |
return makeValue(FullTagTypeUndefined); | |
} | |
static ALWAYS_INLINE JSValue makeNull() | |
{ | |
return makeValue(FullTagTypeNull); | |
} | |
template<typename T> | |
static JSValue fromNumberOutsideIntegerRange(T); | |
#if USE(JSVALUE64) | |
static ALWAYS_INLINE double doubleValue(JSValue v) | |
{ | |
return reinterpretIntptrToDouble(rawValue(v) - DoubleEncodeOffset); | |
} | |
#endif | |
static ALWAYS_INLINE int32_t intValue(JSValue v) | |
{ | |
return static_cast<int32_t>(rawValue(v) >> IntegerPayloadShift); | |
} | |
static ALWAYS_INLINE uint32_t uintValue(JSValue v) | |
{ | |
return static_cast<uint32_t>(rawValue(v) >> IntegerPayloadShift); | |
} | |
static ALWAYS_INLINE bool boolValue(JSValue v) | |
{ | |
return rawValue(v) & ExtendedPayloadBitBoolValue; | |
} | |
static ALWAYS_INLINE intptr_t rawValue(JSValue v) | |
{ | |
return v.immediateValue(); | |
} | |
}; | |
ALWAYS_INLINE JSValue JSImmediate::trueImmediate() { return makeBool(true); } | |
ALWAYS_INLINE JSValue JSImmediate::falseImmediate() { return makeBool(false); } | |
ALWAYS_INLINE JSValue JSImmediate::undefinedImmediate() { return makeUndefined(); } | |
ALWAYS_INLINE JSValue JSImmediate::nullImmediate() { return makeNull(); } | |
ALWAYS_INLINE JSValue JSImmediate::zeroImmediate() { return makeInt(0); } | |
ALWAYS_INLINE JSValue JSImmediate::oneImmediate() { return makeInt(1); } | |
#if USE(JSVALUE64) | |
inline bool doubleToBoolean(double value) | |
{ | |
return value < 0.0 || value > 0.0; | |
} | |
ALWAYS_INLINE bool JSImmediate::toBoolean(JSValue v) | |
{ | |
ASSERT(isImmediate(v)); | |
return isNumber(v) ? isIntegerNumber(v) ? v != zeroImmediate() | |
: doubleToBoolean(doubleValue(v)) : v == trueImmediate(); | |
} | |
#else | |
ALWAYS_INLINE bool JSImmediate::toBoolean(JSValue v) | |
{ | |
ASSERT(isImmediate(v)); | |
return isIntegerNumber(v) ? v != zeroImmediate() : v == trueImmediate(); | |
} | |
#endif | |
ALWAYS_INLINE uint32_t JSImmediate::getTruncatedUInt32(JSValue v) | |
{ | |
// FIXME: should probably be asserting isPositiveIntegerNumber here. | |
ASSERT(isIntegerNumber(v)); | |
return intValue(v); | |
} | |
#if USE(JSVALUE64) | |
template<typename T> | |
inline JSValue JSImmediate::fromNumberOutsideIntegerRange(T value) | |
{ | |
return makeDouble(static_cast<double>(value)); | |
} | |
#else | |
template<typename T> | |
inline JSValue JSImmediate::fromNumberOutsideIntegerRange(T) | |
{ | |
return JSValue(); | |
} | |
#endif | |
ALWAYS_INLINE JSValue JSImmediate::from(char i) | |
{ | |
return makeInt(i); | |
} | |
ALWAYS_INLINE JSValue JSImmediate::from(signed char i) | |
{ | |
return makeInt(i); | |
} | |
ALWAYS_INLINE JSValue JSImmediate::from(unsigned char i) | |
{ | |
return makeInt(i); | |
} | |
ALWAYS_INLINE JSValue JSImmediate::from(short i) | |
{ | |
return makeInt(i); | |
} | |
ALWAYS_INLINE JSValue JSImmediate::from(unsigned short i) | |
{ | |
return makeInt(i); | |
} | |
ALWAYS_INLINE JSValue JSImmediate::from(int i) | |
{ | |
#if !USE(JSVALUE64) | |
if ((i < minImmediateInt) | (i > maxImmediateInt)) | |
return fromNumberOutsideIntegerRange(i); | |
#endif | |
return makeInt(i); | |
} | |
ALWAYS_INLINE JSValue JSImmediate::from(unsigned i) | |
{ | |
if (i > maxImmediateUInt) | |
return fromNumberOutsideIntegerRange(i); | |
return makeInt(i); | |
} | |
ALWAYS_INLINE JSValue JSImmediate::from(long i) | |
{ | |
if ((i < minImmediateInt) | (i > maxImmediateInt)) | |
return fromNumberOutsideIntegerRange(i); | |
return makeInt(i); | |
} | |
ALWAYS_INLINE JSValue JSImmediate::from(unsigned long i) | |
{ | |
if (i > maxImmediateUInt) | |
return fromNumberOutsideIntegerRange(i); | |
return makeInt(i); | |
} | |
ALWAYS_INLINE JSValue JSImmediate::from(long long i) | |
{ | |
if ((i < minImmediateInt) | (i > maxImmediateInt)) | |
return JSValue(); | |
return makeInt(static_cast<intptr_t>(i)); | |
} | |
ALWAYS_INLINE JSValue JSImmediate::from(unsigned long long i) | |
{ | |
if (i > maxImmediateUInt) | |
return fromNumberOutsideIntegerRange(i); | |
return makeInt(static_cast<intptr_t>(i)); | |
} | |
ALWAYS_INLINE JSValue JSImmediate::from(double d) | |
{ | |
const int intVal = static_cast<int>(d); | |
// Check for data loss from conversion to int. | |
if (intVal != d || (!intVal && signbit(d))) | |
return fromNumberOutsideIntegerRange(d); | |
return from(intVal); | |
} | |
ALWAYS_INLINE int32_t JSImmediate::getTruncatedInt32(JSValue v) | |
{ | |
ASSERT(isIntegerNumber(v)); | |
return intValue(v); | |
} | |
ALWAYS_INLINE double JSImmediate::toDouble(JSValue v) | |
{ | |
ASSERT(isImmediate(v)); | |
if (isIntegerNumber(v)) | |
return intValue(v); | |
#if USE(JSVALUE64) | |
if (isNumber(v)) { | |
ASSERT(isDouble(v)); | |
return doubleValue(v); | |
} | |
#else | |
ASSERT(!isNumber(v)); | |
#endif | |
if (rawValue(v) == FullTagTypeUndefined) | |
return nonInlineNaN(); | |
ASSERT(JSImmediate::isBoolean(v) || (v == JSImmediate::nullImmediate())); | |
return rawValue(v) >> ExtendedPayloadShift; | |
} | |
ALWAYS_INLINE bool JSImmediate::getUInt32(JSValue v, uint32_t& i) | |
{ | |
i = uintValue(v); | |
return isPositiveIntegerNumber(v); | |
} | |
ALWAYS_INLINE bool JSImmediate::getTruncatedInt32(JSValue v, int32_t& i) | |
{ | |
i = intValue(v); | |
return isIntegerNumber(v); | |
} | |
ALWAYS_INLINE bool JSImmediate::getTruncatedUInt32(JSValue v, uint32_t& i) | |
{ | |
return getUInt32(v, i); | |
} | |
inline JSValue::JSValue(JSNullTag) | |
{ | |
*this = JSImmediate::nullImmediate(); | |
} | |
inline JSValue::JSValue(JSUndefinedTag) | |
{ | |
*this = JSImmediate::undefinedImmediate(); | |
} | |
inline JSValue::JSValue(JSTrueTag) | |
{ | |
*this = JSImmediate::trueImmediate(); | |
} | |
inline JSValue::JSValue(JSFalseTag) | |
{ | |
*this = JSImmediate::falseImmediate(); | |
} | |
inline bool JSValue::isUndefinedOrNull() const | |
{ | |
return JSImmediate::isUndefinedOrNull(asValue()); | |
} | |
inline bool JSValue::isBoolean() const | |
{ | |
return JSImmediate::isBoolean(asValue()); | |
} | |
inline bool JSValue::isTrue() const | |
{ | |
return asValue() == JSImmediate::trueImmediate(); | |
} | |
inline bool JSValue::isFalse() const | |
{ | |
return asValue() == JSImmediate::falseImmediate(); | |
} | |
inline bool JSValue::getBoolean(bool& v) const | |
{ | |
if (JSImmediate::isBoolean(asValue())) { | |
v = JSImmediate::toBoolean(asValue()); | |
return true; | |
} | |
return false; | |
} | |
inline bool JSValue::getBoolean() const | |
{ | |
return asValue() == jsBoolean(true); | |
} | |
inline bool JSValue::isCell() const | |
{ | |
return !JSImmediate::isImmediate(asValue()); | |
} | |
inline bool JSValue::isInt32() const | |
{ | |
return JSImmediate::isIntegerNumber(asValue()); | |
} | |
inline int32_t JSValue::asInt32() const | |
{ | |
ASSERT(isInt32()); | |
return JSImmediate::getTruncatedInt32(asValue()); | |
} | |
inline bool JSValue::isUInt32() const | |
{ | |
return JSImmediate::isPositiveIntegerNumber(asValue()); | |
} | |
inline uint32_t JSValue::asUInt32() const | |
{ | |
ASSERT(isUInt32()); | |
return JSImmediate::getTruncatedUInt32(asValue()); | |
} | |
class JSFastMath { | |
public: | |
static ALWAYS_INLINE bool canDoFastBitwiseOperations(JSValue v1, JSValue v2) | |
{ | |
return JSImmediate::areBothImmediateIntegerNumbers(v1, v2); | |
} | |
static ALWAYS_INLINE JSValue equal(JSValue v1, JSValue v2) | |
{ | |
ASSERT(canDoFastBitwiseOperations(v1, v2)); | |
return jsBoolean(v1 == v2); | |
} | |
static ALWAYS_INLINE JSValue notEqual(JSValue v1, JSValue v2) | |
{ | |
ASSERT(canDoFastBitwiseOperations(v1, v2)); | |
return jsBoolean(v1 != v2); | |
} | |
static ALWAYS_INLINE JSValue andImmediateNumbers(JSValue v1, JSValue v2) | |
{ | |
ASSERT(canDoFastBitwiseOperations(v1, v2)); | |
return JSImmediate::makeValue(JSImmediate::rawValue(v1) & JSImmediate::rawValue(v2)); | |
} | |
static ALWAYS_INLINE JSValue xorImmediateNumbers(JSValue v1, JSValue v2) | |
{ | |
ASSERT(canDoFastBitwiseOperations(v1, v2)); | |
return JSImmediate::makeValue((JSImmediate::rawValue(v1) ^ JSImmediate::rawValue(v2)) | JSImmediate::TagTypeNumber); | |
} | |
static ALWAYS_INLINE JSValue orImmediateNumbers(JSValue v1, JSValue v2) | |
{ | |
ASSERT(canDoFastBitwiseOperations(v1, v2)); | |
return JSImmediate::makeValue(JSImmediate::rawValue(v1) | JSImmediate::rawValue(v2)); | |
} | |
static ALWAYS_INLINE bool canDoFastRshift(JSValue v1, JSValue v2) | |
{ | |
return JSImmediate::areBothImmediateIntegerNumbers(v1, v2); | |
} | |
static ALWAYS_INLINE bool canDoFastUrshift(JSValue v1, JSValue v2) | |
{ | |
return JSImmediate::areBothImmediateIntegerNumbers(v1, v2) && !(JSImmediate::rawValue(v1) & JSImmediate::signBit); | |
} | |
static ALWAYS_INLINE JSValue rightShiftImmediateNumbers(JSValue val, JSValue shift) | |
{ | |
ASSERT(canDoFastRshift(val, shift) || canDoFastUrshift(val, shift)); | |
#if USE(JSVALUE64) | |
return JSImmediate::makeValue(static_cast<intptr_t>(static_cast<uint32_t>(static_cast<int32_t>(JSImmediate::rawValue(val)) >> ((JSImmediate::rawValue(shift) >> JSImmediate::IntegerPayloadShift) & 0x1f))) | JSImmediate::TagTypeNumber); | |
#else | |
return JSImmediate::makeValue((JSImmediate::rawValue(val) >> ((JSImmediate::rawValue(shift) >> JSImmediate::IntegerPayloadShift) & 0x1f)) | JSImmediate::TagTypeNumber); | |
#endif | |
} | |
static ALWAYS_INLINE bool canDoFastAdditiveOperations(JSValue v) | |
{ | |
// Number is non-negative and an operation involving two of these can't overflow. | |
// Checking for allowed negative numbers takes more time than it's worth on SunSpider. | |
return (JSImmediate::rawValue(v) & (JSImmediate::TagTypeNumber + (JSImmediate::signBit | (JSImmediate::signBit >> 1)))) == JSImmediate::TagTypeNumber; | |
} | |
static ALWAYS_INLINE bool canDoFastAdditiveOperations(JSValue v1, JSValue v2) | |
{ | |
// Number is non-negative and an operation involving two of these can't overflow. | |
// Checking for allowed negative numbers takes more time than it's worth on SunSpider. | |
return canDoFastAdditiveOperations(v1) && canDoFastAdditiveOperations(v2); | |
} | |
static ALWAYS_INLINE JSValue addImmediateNumbers(JSValue v1, JSValue v2) | |
{ | |
ASSERT(canDoFastAdditiveOperations(v1, v2)); | |
return JSImmediate::makeValue(JSImmediate::rawValue(v1) + JSImmediate::rawValue(v2) - JSImmediate::TagTypeNumber); | |
} | |
static ALWAYS_INLINE JSValue subImmediateNumbers(JSValue v1, JSValue v2) | |
{ | |
ASSERT(canDoFastAdditiveOperations(v1, v2)); | |
return JSImmediate::makeValue(JSImmediate::rawValue(v1) - JSImmediate::rawValue(v2) + JSImmediate::TagTypeNumber); | |
} | |
static ALWAYS_INLINE JSValue incImmediateNumber(JSValue v) | |
{ | |
ASSERT(canDoFastAdditiveOperations(v)); | |
return JSImmediate::makeValue(JSImmediate::rawValue(v) + (1 << JSImmediate::IntegerPayloadShift)); | |
} | |
static ALWAYS_INLINE JSValue decImmediateNumber(JSValue v) | |
{ | |
ASSERT(canDoFastAdditiveOperations(v)); | |
return JSImmediate::makeValue(JSImmediate::rawValue(v) - (1 << JSImmediate::IntegerPayloadShift)); | |
} | |
}; | |
} // namespace JSC | |
#endif // !USE(JSVALUE32_64) | |
#endif // JSImmediate_h |