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Diffstat (limited to 'Source/JavaScriptCore/jit/JITMulGenerator.cpp')
| -rw-r--r-- | Source/JavaScriptCore/jit/JITMulGenerator.cpp | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/Source/JavaScriptCore/jit/JITMulGenerator.cpp b/Source/JavaScriptCore/jit/JITMulGenerator.cpp new file mode 100644 index 000000000..93c69e297 --- /dev/null +++ b/Source/JavaScriptCore/jit/JITMulGenerator.cpp @@ -0,0 +1,254 @@ +/* + * Copyright (C) 2015-2016 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 "JITMulGenerator.h" + +#if ENABLE(JIT) + +#include "ArithProfile.h" +#include "JITMathIC.h" + +namespace JSC { + +JITMathICInlineResult JITMulGenerator::generateInline(CCallHelpers& jit, MathICGenerationState& state, const ArithProfile* arithProfile) +{ + // We default to speculating int32. + ObservedType lhs = ObservedType().withInt32(); + ObservedType rhs = ObservedType().withInt32(); + if (arithProfile) { + lhs = arithProfile->lhsObservedType(); + rhs = arithProfile->rhsObservedType(); + } + + if (lhs.isOnlyNonNumber() && rhs.isOnlyNonNumber()) + return JITMathICInlineResult::DontGenerate; + + if (lhs.isOnlyNumber() && rhs.isOnlyNumber()) { + if (!jit.supportsFloatingPoint()) + return JITMathICInlineResult::DontGenerate; + + if (!m_leftOperand.definitelyIsNumber()) + state.slowPathJumps.append(jit.branchIfNotNumber(m_left, m_scratchGPR)); + if (!m_rightOperand.definitelyIsNumber()) + state.slowPathJumps.append(jit.branchIfNotNumber(m_right, m_scratchGPR)); + state.slowPathJumps.append(jit.branchIfInt32(m_left)); + state.slowPathJumps.append(jit.branchIfInt32(m_right)); + jit.unboxDoubleNonDestructive(m_left, m_leftFPR, m_scratchGPR, m_scratchFPR); + jit.unboxDoubleNonDestructive(m_right, m_rightFPR, m_scratchGPR, m_scratchFPR); + jit.mulDouble(m_rightFPR, m_leftFPR); + jit.boxDouble(m_leftFPR, m_result); + + return JITMathICInlineResult::GeneratedFastPath; + } + + if ((lhs.isOnlyInt32() || m_leftOperand.isPositiveConstInt32()) && (rhs.isOnlyInt32() || m_rightOperand.isPositiveConstInt32())) { + ASSERT(!m_leftOperand.isPositiveConstInt32() || !m_rightOperand.isPositiveConstInt32()); + if (!m_leftOperand.isPositiveConstInt32()) + state.slowPathJumps.append(jit.branchIfNotInt32(m_left)); + if (!m_rightOperand.isPositiveConstInt32()) + state.slowPathJumps.append(jit.branchIfNotInt32(m_right)); + + if (m_leftOperand.isPositiveConstInt32() || m_rightOperand.isPositiveConstInt32()) { + JSValueRegs var = m_leftOperand.isPositiveConstInt32() ? m_right : m_left; + int32_t constValue = m_leftOperand.isPositiveConstInt32() ? m_leftOperand.asConstInt32() : m_rightOperand.asConstInt32(); + state.slowPathJumps.append(jit.branchMul32(CCallHelpers::Overflow, var.payloadGPR(), CCallHelpers::Imm32(constValue), m_scratchGPR)); + } else { + state.slowPathJumps.append(jit.branchMul32(CCallHelpers::Overflow, m_right.payloadGPR(), m_left.payloadGPR(), m_scratchGPR)); + state.slowPathJumps.append(jit.branchTest32(CCallHelpers::Zero, m_scratchGPR)); // Go slow if potential negative zero. + } + jit.boxInt32(m_scratchGPR, m_result); + + return JITMathICInlineResult::GeneratedFastPath; + } + + return JITMathICInlineResult::GenerateFullSnippet; +} + +bool JITMulGenerator::generateFastPath(CCallHelpers& jit, CCallHelpers::JumpList& endJumpList, CCallHelpers::JumpList& slowPathJumpList, const ArithProfile* arithProfile, bool shouldEmitProfiling) +{ + ASSERT(m_scratchGPR != InvalidGPRReg); + ASSERT(m_scratchGPR != m_left.payloadGPR()); + ASSERT(m_scratchGPR != m_right.payloadGPR()); +#if USE(JSVALUE64) + ASSERT(m_scratchGPR != m_result.payloadGPR()); +#else + ASSERT(m_scratchGPR != m_left.tagGPR()); + ASSERT(m_scratchGPR != m_right.tagGPR()); + ASSERT(m_scratchFPR != InvalidFPRReg); +#endif + + ASSERT(!m_leftOperand.isPositiveConstInt32() || !m_rightOperand.isPositiveConstInt32()); + + if (!m_leftOperand.mightBeNumber() || !m_rightOperand.mightBeNumber()) + return false; + + if (m_leftOperand.isPositiveConstInt32() || m_rightOperand.isPositiveConstInt32()) { + JSValueRegs var = m_leftOperand.isPositiveConstInt32() ? m_right : m_left; + SnippetOperand& varOpr = m_leftOperand.isPositiveConstInt32() ? m_rightOperand : m_leftOperand; + SnippetOperand& constOpr = m_leftOperand.isPositiveConstInt32() ? m_leftOperand : m_rightOperand; + + // Try to do intVar * intConstant. + CCallHelpers::Jump notInt32 = jit.branchIfNotInt32(var); + + GPRReg multiplyResultGPR = m_result.payloadGPR(); + if (multiplyResultGPR == var.payloadGPR()) + multiplyResultGPR = m_scratchGPR; + + slowPathJumpList.append(jit.branchMul32(CCallHelpers::Overflow, var.payloadGPR(), CCallHelpers::Imm32(constOpr.asConstInt32()), multiplyResultGPR)); + + jit.boxInt32(multiplyResultGPR, m_result); + endJumpList.append(jit.jump()); + + if (!jit.supportsFloatingPoint()) { + slowPathJumpList.append(notInt32); + return true; + } + + // Try to do doubleVar * double(intConstant). + notInt32.link(&jit); + if (!varOpr.definitelyIsNumber()) + slowPathJumpList.append(jit.branchIfNotNumber(var, m_scratchGPR)); + + jit.unboxDoubleNonDestructive(var, m_leftFPR, m_scratchGPR, m_scratchFPR); + + jit.move(CCallHelpers::Imm32(constOpr.asConstInt32()), m_scratchGPR); + jit.convertInt32ToDouble(m_scratchGPR, m_rightFPR); + + // Fall thru to doubleVar * doubleVar. + + } else { + ASSERT(!m_leftOperand.isPositiveConstInt32() && !m_rightOperand.isPositiveConstInt32()); + + CCallHelpers::Jump leftNotInt; + CCallHelpers::Jump rightNotInt; + + // Try to do intVar * intVar. + leftNotInt = jit.branchIfNotInt32(m_left); + rightNotInt = jit.branchIfNotInt32(m_right); + + slowPathJumpList.append(jit.branchMul32(CCallHelpers::Overflow, m_right.payloadGPR(), m_left.payloadGPR(), m_scratchGPR)); + slowPathJumpList.append(jit.branchTest32(CCallHelpers::Zero, m_scratchGPR)); // Go slow if potential negative zero. + + jit.boxInt32(m_scratchGPR, m_result); + endJumpList.append(jit.jump()); + + if (!jit.supportsFloatingPoint()) { + slowPathJumpList.append(leftNotInt); + slowPathJumpList.append(rightNotInt); + return true; + } + + leftNotInt.link(&jit); + if (!m_leftOperand.definitelyIsNumber()) + slowPathJumpList.append(jit.branchIfNotNumber(m_left, m_scratchGPR)); + if (!m_rightOperand.definitelyIsNumber()) + slowPathJumpList.append(jit.branchIfNotNumber(m_right, m_scratchGPR)); + + jit.unboxDoubleNonDestructive(m_left, m_leftFPR, m_scratchGPR, m_scratchFPR); + CCallHelpers::Jump rightIsDouble = jit.branchIfNotInt32(m_right); + + jit.convertInt32ToDouble(m_right.payloadGPR(), m_rightFPR); + CCallHelpers::Jump rightWasInteger = jit.jump(); + + rightNotInt.link(&jit); + if (!m_rightOperand.definitelyIsNumber()) + slowPathJumpList.append(jit.branchIfNotNumber(m_right, m_scratchGPR)); + + jit.convertInt32ToDouble(m_left.payloadGPR(), m_leftFPR); + + rightIsDouble.link(&jit); + jit.unboxDoubleNonDestructive(m_right, m_rightFPR, m_scratchGPR, m_scratchFPR); + + rightWasInteger.link(&jit); + + // Fall thru to doubleVar * doubleVar. + } + + // Do doubleVar * doubleVar. + jit.mulDouble(m_rightFPR, m_leftFPR); + + if (!arithProfile || !shouldEmitProfiling) + jit.boxDouble(m_leftFPR, m_result); + else { + // The Int52 overflow check below intentionally omits 1ll << 51 as a valid negative Int52 value. + // Therefore, we will get a false positive if the result is that value. This is intentionally + // done to simplify the checking algorithm. + + const int64_t negativeZeroBits = 1ll << 63; +#if USE(JSVALUE64) + jit.moveDoubleTo64(m_leftFPR, m_result.payloadGPR()); + + CCallHelpers::Jump notNegativeZero = jit.branch64(CCallHelpers::NotEqual, m_result.payloadGPR(), CCallHelpers::TrustedImm64(negativeZeroBits)); + + jit.or32(CCallHelpers::TrustedImm32(ArithProfile::NegZeroDouble), CCallHelpers::AbsoluteAddress(arithProfile->addressOfBits())); + CCallHelpers::Jump done = jit.jump(); + + notNegativeZero.link(&jit); + jit.or32(CCallHelpers::TrustedImm32(ArithProfile::NonNegZeroDouble), CCallHelpers::AbsoluteAddress(arithProfile->addressOfBits())); + + jit.move(m_result.payloadGPR(), m_scratchGPR); + jit.urshiftPtr(CCallHelpers::Imm32(52), m_scratchGPR); + jit.and32(CCallHelpers::Imm32(0x7ff), m_scratchGPR); + CCallHelpers::Jump noInt52Overflow = jit.branch32(CCallHelpers::LessThanOrEqual, m_scratchGPR, CCallHelpers::TrustedImm32(0x431)); + + jit.or32(CCallHelpers::TrustedImm32(ArithProfile::Int52Overflow), CCallHelpers::AbsoluteAddress(arithProfile->addressOfBits())); + noInt52Overflow.link(&jit); + + done.link(&jit); + jit.sub64(GPRInfo::tagTypeNumberRegister, m_result.payloadGPR()); // Box the double. +#else + jit.boxDouble(m_leftFPR, m_result); + CCallHelpers::JumpList notNegativeZero; + notNegativeZero.append(jit.branch32(CCallHelpers::NotEqual, m_result.payloadGPR(), CCallHelpers::TrustedImm32(0))); + notNegativeZero.append(jit.branch32(CCallHelpers::NotEqual, m_result.tagGPR(), CCallHelpers::TrustedImm32(negativeZeroBits >> 32))); + + jit.or32(CCallHelpers::TrustedImm32(ArithProfile::NegZeroDouble), CCallHelpers::AbsoluteAddress(arithProfile->addressOfBits())); + CCallHelpers::Jump done = jit.jump(); + + notNegativeZero.link(&jit); + jit.or32(CCallHelpers::TrustedImm32(ArithProfile::NonNegZeroDouble), CCallHelpers::AbsoluteAddress(arithProfile->addressOfBits())); + + jit.move(m_result.tagGPR(), m_scratchGPR); + jit.urshiftPtr(CCallHelpers::Imm32(52 - 32), m_scratchGPR); + jit.and32(CCallHelpers::Imm32(0x7ff), m_scratchGPR); + CCallHelpers::Jump noInt52Overflow = jit.branch32(CCallHelpers::LessThanOrEqual, m_scratchGPR, CCallHelpers::TrustedImm32(0x431)); + + jit.or32(CCallHelpers::TrustedImm32(ArithProfile::Int52Overflow), CCallHelpers::AbsoluteAddress(arithProfile->addressOfBits())); + + endJumpList.append(noInt52Overflow); + if (m_scratchGPR == m_result.tagGPR() || m_scratchGPR == m_result.payloadGPR()) + jit.boxDouble(m_leftFPR, m_result); + + endJumpList.append(done); +#endif + } + + return true; +} + +} // namespace JSC + +#endif // ENABLE(JIT) |