LInstruction* LChunkBuilder::DoDivByPowerOf2I(HDiv* instr) {
- ASSERT(instr->representation().IsSmiOrInteger32());
+ ASSERT(instr->representation().IsInteger32());
ASSERT(instr->left()->representation().Equals(instr->representation()));
ASSERT(instr->right()->representation().Equals(instr->representation()));
LOperand* dividend = UseRegister(instr->left());
}
+LInstruction* LChunkBuilder::DoDivByConstI(HDiv* instr) {
+ ASSERT(instr->representation().IsInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
+ LOperand* dividend = UseRegister(instr->left());
+ int32_t divisor = instr->right()->GetInteger32Constant();
+ bool truncating = instr->CheckFlag(HInstruction::kAllUsesTruncatingToInt32);
+ LOperand* temp = truncating ? NULL : TempRegister();
+ LInstruction* result =
+ DefineAsRegister(new(zone()) LDivByConstI(dividend, divisor, temp));
+ bool can_deopt =
+ divisor == 0 ||
+ (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ instr->left()->RangeCanInclude(0) && divisor < 0) ||
+ !truncating;
+ return can_deopt ? AssignEnvironment(result) : result;
+}
+
+
LInstruction* LChunkBuilder::DoDivI(HBinaryOperation* instr) {
ASSERT(instr->representation().IsSmiOrInteger32());
ASSERT(instr->left()->representation().Equals(instr->representation()));
LInstruction* LChunkBuilder::DoDiv(HDiv* instr) {
if (instr->representation().IsSmiOrInteger32()) {
- // TODO(all): Add Smi support to DoDivI and turn this into a ternary.
- if (instr->RightIsPowerOf2()) return DoDivByPowerOf2I(instr);
- if (instr->representation().IsInteger32()) return DoDivI(instr);
- return DoArithmeticT(Token::DIV, instr);
+ if (instr->RightIsPowerOf2()) {
+ return DoDivByPowerOf2I(instr);
+ } else if (instr->right()->IsConstant()) {
+ return DoDivByConstI(instr);
+ } else {
+ return DoDivI(instr);
+ }
} else if (instr->representation().IsDouble()) {
return DoArithmeticD(Token::DIV, instr);
} else {
LInstruction* LChunkBuilder::DoFlooringDivByPowerOf2I(HMathFloorOfDiv* instr) {
+ ASSERT(instr->representation().IsInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
LOperand* dividend = UseRegisterAtStart(instr->left());
int32_t divisor = instr->right()->GetInteger32Constant();
LInstruction* result =
}
+LInstruction* LChunkBuilder::DoFlooringDivByConstI(HMathFloorOfDiv* instr) {
+ ASSERT(instr->representation().IsInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
+ LOperand* dividend = UseRegister(instr->left());
+ int32_t divisor = instr->right()->GetInteger32Constant();
+ LInstruction* result =
+ DefineAsRegister(new(zone()) LFlooringDivByConstI(dividend, divisor));
+ bool can_deopt =
+ divisor == 0 ||
+ (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ instr->left()->RangeCanInclude(0) && divisor < 0);
+ return can_deopt ? AssignEnvironment(result) : result;
+}
+
+
LInstruction* LChunkBuilder::DoFlooringDivI(HMathFloorOfDiv* instr) {
LOperand* dividend = UseRegister(instr->left());
LOperand* divisor = UseRegister(instr->right());
if (instr->RightIsPowerOf2()) {
return DoFlooringDivByPowerOf2I(instr);
} else if (instr->right()->IsConstant()) {
- // TODO(svenpanne) Do something more efficient in this case.
- return DoFlooringDivI(instr);
+ return DoFlooringDivByConstI(instr);
} else {
return DoFlooringDivI(instr);
}
LInstruction* LChunkBuilder::DoModByPowerOf2I(HMod* instr) {
- ASSERT(instr->representation().IsSmiOrInteger32());
+ ASSERT(instr->representation().IsInteger32());
ASSERT(instr->left()->representation().Equals(instr->representation()));
ASSERT(instr->right()->representation().Equals(instr->representation()));
LOperand* dividend = UseRegisterAtStart(instr->left());
}
+LInstruction* LChunkBuilder::DoModByConstI(HMod* instr) {
+ ASSERT(instr->representation().IsInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
+ LOperand* dividend = UseRegister(instr->left());
+ int32_t divisor = instr->right()->GetInteger32Constant();
+ LOperand* temp = TempRegister();
+ LInstruction* result =
+ DefineAsRegister(new(zone()) LModByConstI(dividend, divisor, temp));
+ bool can_deopt =
+ divisor == 0 ||
+ (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ instr->left()->CanBeNegative());
+ return can_deopt ? AssignEnvironment(result) : result;
+}
+
+
LInstruction* LChunkBuilder::DoModI(HMod* instr) {
ASSERT(instr->representation().IsSmiOrInteger32());
ASSERT(instr->left()->representation().Equals(instr->representation()));
LInstruction* LChunkBuilder::DoMod(HMod* instr) {
if (instr->representation().IsSmiOrInteger32()) {
- // TODO(all): Add Smi support to DoDivI and turn this into a ternary.
- if (instr->RightIsPowerOf2()) return DoModByPowerOf2I(instr);
- if (instr->representation().IsInteger32()) return DoModI(instr);
- return DoArithmeticT(Token::MOD, instr);
+ if (instr->RightIsPowerOf2()) {
+ return DoModByPowerOf2I(instr);
+ } else if (instr->right()->IsConstant()) {
+ return DoModByConstI(instr);
+ } else {
+ return DoModI(instr);
+ }
} else if (instr->representation().IsDouble()) {
return DoArithmeticD(Token::MOD, instr);
} else {
V(DebugBreak) \
V(DeclareGlobals) \
V(Deoptimize) \
+ V(DivByConstI) \
V(DivByPowerOf2I) \
V(DivI) \
V(DoubleBits) \
V(Drop) \
V(Dummy) \
V(DummyUse) \
+ V(FlooringDivByConstI) \
V(FlooringDivByPowerOf2I) \
V(FlooringDivI) \
V(ForInCacheArray) \
V(MathPowHalf) \
V(MathRound) \
V(MathSqrt) \
+ V(ModByConstI) \
V(ModByPowerOf2I) \
V(ModI) \
V(MulConstIS) \
};
+class LDivByConstI V8_FINAL : public LTemplateInstruction<1, 1, 1> {
+ public:
+ LDivByConstI(LOperand* dividend, int32_t divisor, LOperand* temp) {
+ inputs_[0] = dividend;
+ divisor_ = divisor;
+ temps_[0] = temp;
+ }
+
+ LOperand* dividend() { return inputs_[0]; }
+ int32_t divisor() const { return divisor_; }
+ LOperand* temp() { return temps_[0]; }
+
+ DECLARE_CONCRETE_INSTRUCTION(DivByConstI, "div-by-const-i")
+ DECLARE_HYDROGEN_ACCESSOR(Div)
+
+ private:
+ int32_t divisor_;
+};
+
+
class LDivI V8_FINAL : public LTemplateInstruction<1, 2, 1> {
public:
LDivI(LOperand* left, LOperand* right, LOperand* temp) {
};
+class LFlooringDivByConstI V8_FINAL : public LTemplateInstruction<1, 1, 0> {
+ public:
+ LFlooringDivByConstI(LOperand* dividend, int32_t divisor) {
+ inputs_[0] = dividend;
+ divisor_ = divisor;
+ }
+
+ LOperand* dividend() { return inputs_[0]; }
+ int32_t divisor() const { return divisor_; }
+ LOperand* temp1() { return temps_[0]; }
+
+ DECLARE_CONCRETE_INSTRUCTION(FlooringDivByConstI, "flooring-div-by-const-i")
+ DECLARE_HYDROGEN_ACCESSOR(MathFloorOfDiv)
+
+ private:
+ int32_t divisor_;
+};
+
+
class LFlooringDivI V8_FINAL : public LTemplateInstruction<1, 2, 1> {
public:
LFlooringDivI(LOperand* dividend, LOperand* divisor, LOperand* temp) {
};
+class LModByConstI V8_FINAL : public LTemplateInstruction<1, 1, 1> {
+ public:
+ LModByConstI(LOperand* dividend, int32_t divisor, LOperand* temp) {
+ inputs_[0] = dividend;
+ divisor_ = divisor;
+ temps_[0] = temp;
+ }
+
+ LOperand* dividend() { return inputs_[0]; }
+ int32_t divisor() const { return divisor_; }
+ LOperand* temp() { return temps_[0]; }
+
+ DECLARE_CONCRETE_INSTRUCTION(ModByConstI, "mod-by-const-i")
+ DECLARE_HYDROGEN_ACCESSOR(Mod)
+
+ private:
+ int32_t divisor_;
+};
+
+
class LModI V8_FINAL : public LTemplateInstruction<1, 2, 0> {
public:
LModI(LOperand* left, LOperand* right) {
#undef DECLARE_DO
LInstruction* DoDivByPowerOf2I(HDiv* instr);
+ LInstruction* DoDivByConstI(HDiv* instr);
LInstruction* DoDivI(HBinaryOperation* instr);
LInstruction* DoModByPowerOf2I(HMod* instr);
+ LInstruction* DoModByConstI(HMod* instr);
LInstruction* DoModI(HMod* instr);
LInstruction* DoFlooringDivByPowerOf2I(HMathFloorOfDiv* instr);
+ LInstruction* DoFlooringDivByConstI(HMathFloorOfDiv* instr);
LInstruction* DoFlooringDivI(HMathFloorOfDiv* instr);
static bool HasMagicNumberForDivision(int32_t divisor);
}
+void LCodeGen::DeoptimizeIfNotZero(Register rt, LEnvironment* environment) {
+ DeoptimizeBranch(environment, reg_not_zero, rt);
+}
+
+
void LCodeGen::DeoptimizeIfNegative(Register rt, LEnvironment* environment) {
int sign_bit = rt.Is64Bits() ? kXSignBit : kWSignBit;
DeoptimizeBranch(environment, reg_bit_set, rt, sign_bit);
}
+void LCodeGen::DoDivByConstI(LDivByConstI* instr) {
+ Register dividend = ToRegister32(instr->dividend());
+ int32_t divisor = instr->divisor();
+ Register result = ToRegister32(instr->result());
+ ASSERT(!AreAliased(dividend, result));
+
+ if (divisor == 0) {
+ Deoptimize(instr->environment());
+ return;
+ }
+
+ // Check for (0 / -x) that will produce negative zero.
+ HDiv* hdiv = instr->hydrogen();
+ if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ hdiv->left()->RangeCanInclude(0) && divisor < 0) {
+ DeoptimizeIfZero(dividend, instr->environment());
+ }
+
+ __ FlooringDiv(result, dividend, Abs(divisor));
+ __ Add(result, result, Operand(dividend, LSR, 31));
+ if (divisor < 0) __ Neg(result, result);
+
+ if (!hdiv->CheckFlag(HInstruction::kAllUsesTruncatingToInt32)) {
+ Register temp = ToRegister32(instr->temp());
+ ASSERT(!AreAliased(dividend, result, temp));
+ __ Sxtw(dividend.X(), dividend);
+ __ Mov(temp, divisor);
+ __ Smsubl(temp.X(), result, temp, dividend.X());
+ DeoptimizeIfNotZero(temp, instr->environment());
+ }
+}
+
+
void LCodeGen::DoDivI(LDivI* instr) {
Register dividend = ToRegister32(instr->left());
Register divisor = ToRegister32(instr->right());
}
+void LCodeGen::DoFlooringDivByConstI(LFlooringDivByConstI* instr) {
+ Register dividend = ToRegister32(instr->dividend());
+ int32_t divisor = instr->divisor();
+ Register result = ToRegister32(instr->result());
+ ASSERT(!AreAliased(dividend, result));
+
+ if (divisor == 0) {
+ Deoptimize(instr->environment());
+ return;
+ }
+
+ // Check for (0 / -x) that will produce negative zero.
+ HMathFloorOfDiv* hdiv = instr->hydrogen();
+ if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ hdiv->left()->RangeCanInclude(0) && divisor < 0) {
+ __ Cmp(dividend, 0);
+ DeoptimizeIf(eq, instr->environment());
+ }
+
+ __ FlooringDiv(result, dividend, divisor);
+}
+
+
void LCodeGen::DoFlooringDivI(LFlooringDivI* instr) {
Register dividend = ToRegister32(instr->dividend());
Register divisor = ToRegister32(instr->divisor());
}
+void LCodeGen::DoModByConstI(LModByConstI* instr) {
+ Register dividend = ToRegister32(instr->dividend());
+ int32_t divisor = instr->divisor();
+ Register result = ToRegister32(instr->result());
+ Register temp = ToRegister32(instr->temp());
+ ASSERT(!AreAliased(dividend, result, temp));
+
+ if (divisor == 0) {
+ Deoptimize(instr->environment());
+ return;
+ }
+
+ __ FlooringDiv(result, dividend, Abs(divisor));
+ __ Add(result, result, Operand(dividend, LSR, 31));
+ __ Sxtw(dividend.X(), dividend);
+ __ Mov(temp, Abs(divisor));
+ __ Smsubl(result.X(), result, temp, dividend.X());
+
+ // Check for negative zero.
+ HMod* hmod = instr->hydrogen();
+ if (hmod->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ hmod->left()->CanBeNegative()) {
+ Label remainder_not_zero;
+ __ Cbnz(result, &remainder_not_zero);
+ DeoptimizeIfNegative(dividend, instr->environment());
+ __ bind(&remainder_not_zero);
+ }
+}
+
+
void LCodeGen::DoModI(LModI* instr) {
Register dividend = ToRegister32(instr->left());
Register divisor = ToRegister32(instr->right());
Deoptimizer::BailoutType* override_bailout_type = NULL);
void DeoptimizeIf(Condition cc, LEnvironment* environment);
void DeoptimizeIfZero(Register rt, LEnvironment* environment);
+ void DeoptimizeIfNotZero(Register rt, LEnvironment* environment);
void DeoptimizeIfNegative(Register rt, LEnvironment* environment);
void DeoptimizeIfSmi(Register rt, LEnvironment* environment);
void DeoptimizeIfNotSmi(Register rt, LEnvironment* environment);
#endif
+void MacroAssembler::FlooringDiv(Register result,
+ Register dividend,
+ int32_t divisor) {
+ Register tmp = WTmp0();
+ ASSERT(!AreAliased(result, dividend, tmp));
+ ASSERT(result.Is32Bits() && dividend.Is32Bits());
+ MultiplierAndShift ms(divisor);
+ Mov(tmp, Operand(ms.multiplier()));
+ Smull(result.X(), dividend, tmp);
+ Asr(result.X(), result.X(), 32);
+ if (divisor > 0 && ms.multiplier() < 0) Add(result, result, dividend);
+ if (divisor < 0 && ms.multiplier() > 0) Sub(result, result, dividend);
+ if (ms.shift() > 0) Asr(result, result, ms.shift());
+}
+
+
#undef __
#define __ masm->
void LoadContext(Register dst, int context_chain_length);
+ // Emit code for a flooring division by a constant. The dividend register is
+ // unchanged and Tmp0() gets clobbered. Dividend and result must be different.
+ void FlooringDiv(Register result, Register dividend, int32_t divisor);
+
// ---------------------------------------------------------------------------
// StatsCounter support
}
+LInstruction* LChunkBuilder::DoDivByConstI(HDiv* instr) {
+ ASSERT(instr->representation().IsInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
+ LOperand* dividend = UseRegister(instr->left());
+ int32_t divisor = instr->right()->GetInteger32Constant();
+ LInstruction* result =
+ DefineAsRegister(new(zone()) LDivByConstI(dividend, divisor));
+ bool can_deopt =
+ divisor == 0 ||
+ (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ instr->left()->RangeCanInclude(0) && divisor < 0) ||
+ !instr->CheckFlag(HInstruction::kAllUsesTruncatingToInt32);
+ return can_deopt ? AssignEnvironment(result) : result;
+}
+
+
LInstruction* LChunkBuilder::DoDivI(HBinaryOperation* instr) {
ASSERT(instr->representation().IsSmiOrInteger32());
ASSERT(instr->left()->representation().Equals(instr->representation()));
LInstruction* LChunkBuilder::DoDiv(HDiv* instr) {
if (instr->representation().IsSmiOrInteger32()) {
- return instr->RightIsPowerOf2() ? DoDivByPowerOf2I(instr) : DoDivI(instr);
+ if (instr->RightIsPowerOf2()) {
+ return DoDivByPowerOf2I(instr);
+ } else if (instr->right()->IsConstant()) {
+ return DoDivByConstI(instr);
+ } else {
+ return DoDivI(instr);
+ }
} else if (instr->representation().IsDouble()) {
return DoArithmeticD(Token::DIV, instr);
} else {
}
-bool LChunkBuilder::HasMagicNumberForDivisor(int32_t divisor) {
- uint32_t divisor_abs = abs(divisor);
- // Dividing by 0 or powers of 2 is easy.
- if (divisor == 0 || IsPowerOf2(divisor_abs)) return true;
-
- // We have magic numbers for a few specific divisors.
- // Details and proofs can be found in:
- // - Hacker's Delight, Henry S. Warren, Jr.
- // - The PowerPC Compiler Writer’s Guide
- // and probably many others.
- //
- // We handle
- // <divisor with magic numbers> * <power of 2>
- // but not
- // <divisor with magic numbers> * <other divisor with magic numbers>
- int32_t power_of_2_factor =
- CompilerIntrinsics::CountTrailingZeros(divisor_abs);
- DivMagicNumbers magic_numbers =
- DivMagicNumberFor(divisor_abs >> power_of_2_factor);
- return magic_numbers.M != InvalidDivMagicNumber.M;
-}
-
-
LInstruction* LChunkBuilder::DoFlooringDivByPowerOf2I(HMathFloorOfDiv* instr) {
LOperand* dividend = UseRegisterAtStart(instr->left());
int32_t divisor = instr->right()->GetInteger32Constant();
LInstruction* LChunkBuilder::DoFlooringDivByConstI(HMathFloorOfDiv* instr) {
+ ASSERT(instr->representation().IsInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
LOperand* dividend = UseRegister(instr->left());
- LOperand* divisor = CpuFeatures::IsSupported(SUDIV)
- ? UseRegister(instr->right())
- : UseOrConstant(instr->right());
- LOperand* remainder = TempRegister();
+ int32_t divisor = instr->right()->GetInteger32Constant();
LInstruction* result =
- DefineAsRegister(
- new(zone()) LFlooringDivByConstI(dividend, divisor, remainder));
- return AssignEnvironment(result);
+ DefineAsRegister(new(zone()) LFlooringDivByConstI(dividend, divisor));
+ bool can_deopt =
+ divisor == 0 ||
+ (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ instr->left()->RangeCanInclude(0) && divisor < 0);
+ return can_deopt ? AssignEnvironment(result) : result;
}
if (instr->RightIsPowerOf2()) {
return DoFlooringDivByPowerOf2I(instr);
} else if (instr->right()->IsConstant()) {
- // LMathFloorOfDiv can currently only handle a subset of divisors, so fall
- // back to a flooring division in all other cases.
- return (CpuFeatures::IsSupported(SUDIV) ||
- HasMagicNumberForDivisor(instr->right()->GetInteger32Constant()))
- ? DoFlooringDivByConstI(instr)
- : DoDivI(instr);
+ return DoFlooringDivByConstI(instr);
} else {
return DoDivI(instr);
}
}
+LInstruction* LChunkBuilder::DoModByConstI(HMod* instr) {
+ ASSERT(instr->representation().IsSmiOrInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
+ LOperand* dividend = UseRegister(instr->left());
+ int32_t divisor = instr->right()->GetInteger32Constant();
+ LInstruction* result =
+ DefineAsRegister(new(zone()) LModByConstI(dividend, divisor));
+ bool can_deopt =
+ divisor == 0 ||
+ (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ instr->left()->CanBeNegative());
+ return can_deopt ? AssignEnvironment(result) : result;
+}
+
+
LInstruction* LChunkBuilder::DoModI(HMod* instr) {
ASSERT(instr->representation().IsSmiOrInteger32());
ASSERT(instr->left()->representation().Equals(instr->representation()));
LInstruction* LChunkBuilder::DoMod(HMod* instr) {
if (instr->representation().IsSmiOrInteger32()) {
- return instr->RightIsPowerOf2() ? DoModByPowerOf2I(instr) : DoModI(instr);
+ if (instr->RightIsPowerOf2()) {
+ return DoModByPowerOf2I(instr);
+ } else if (instr->right()->IsConstant()) {
+ return DoModByConstI(instr);
+ } else {
+ return DoModI(instr);
+ }
} else if (instr->representation().IsDouble()) {
return DoArithmeticD(Token::MOD, instr);
} else {
V(DebugBreak) \
V(DeclareGlobals) \
V(Deoptimize) \
+ V(DivByConstI) \
V(DivByPowerOf2I) \
V(DivI) \
V(DoubleBits) \
V(MathPowHalf) \
V(MathRound) \
V(MathSqrt) \
+ V(ModByConstI) \
V(ModByPowerOf2I) \
V(ModI) \
V(MulI) \
};
+class LModByConstI V8_FINAL : public LTemplateInstruction<1, 1, 0> {
+ public:
+ LModByConstI(LOperand* dividend, int32_t divisor) {
+ inputs_[0] = dividend;
+ divisor_ = divisor;
+ }
+
+ LOperand* dividend() { return inputs_[0]; }
+ int32_t divisor() const { return divisor_; }
+
+ DECLARE_CONCRETE_INSTRUCTION(ModByConstI, "mod-by-const-i")
+ DECLARE_HYDROGEN_ACCESSOR(Mod)
+
+ private:
+ int32_t divisor_;
+};
+
+
class LModI V8_FINAL : public LTemplateInstruction<1, 2, 2> {
public:
LModI(LOperand* left, LOperand* right, LOperand* temp, LOperand* temp2) {
};
+class LDivByConstI V8_FINAL : public LTemplateInstruction<1, 1, 0> {
+ public:
+ LDivByConstI(LOperand* dividend, int32_t divisor) {
+ inputs_[0] = dividend;
+ divisor_ = divisor;
+ }
+
+ LOperand* dividend() { return inputs_[0]; }
+ int32_t divisor() const { return divisor_; }
+
+ DECLARE_CONCRETE_INSTRUCTION(DivByConstI, "div-by-const-i")
+ DECLARE_HYDROGEN_ACCESSOR(Div)
+
+ private:
+ int32_t divisor_;
+};
+
+
class LDivI V8_FINAL : public LTemplateInstruction<1, 2, 1> {
public:
LDivI(LOperand* left, LOperand* right, LOperand* temp) {
};
-class LFlooringDivByConstI V8_FINAL : public LTemplateInstruction<1, 2, 1> {
+class LFlooringDivByConstI V8_FINAL : public LTemplateInstruction<1, 1, 0> {
public:
- LFlooringDivByConstI(LOperand* dividend, LOperand* divisor, LOperand* temp) {
+ LFlooringDivByConstI(LOperand* dividend, int32_t divisor) {
inputs_[0] = dividend;
- inputs_[1] = divisor;
- temps_[0] = temp;
+ divisor_ = divisor;
}
LOperand* dividend() { return inputs_[0]; }
- LOperand* divisor() { return inputs_[1]; }
- LOperand* temp() { return temps_[0]; }
+ int32_t divisor() const { return divisor_; }
+ LOperand* temp1() { return temps_[0]; }
DECLARE_CONCRETE_INSTRUCTION(FlooringDivByConstI, "flooring-div-by-const-i")
DECLARE_HYDROGEN_ACCESSOR(MathFloorOfDiv)
+
+ private:
+ int32_t divisor_;
};
LInstruction* DoMathPowHalf(HUnaryMathOperation* instr);
LInstruction* DoMathClz32(HUnaryMathOperation* instr);
LInstruction* DoDivByPowerOf2I(HDiv* instr);
+ LInstruction* DoDivByConstI(HDiv* instr);
LInstruction* DoDivI(HBinaryOperation* instr);
LInstruction* DoModByPowerOf2I(HMod* instr);
+ LInstruction* DoModByConstI(HMod* instr);
LInstruction* DoModI(HMod* instr);
LInstruction* DoFlooringDivByPowerOf2I(HMathFloorOfDiv* instr);
LInstruction* DoFlooringDivByConstI(HMathFloorOfDiv* instr);
}
+void LCodeGen::DoModByConstI(LModByConstI* instr) {
+ Register dividend = ToRegister(instr->dividend());
+ int32_t divisor = instr->divisor();
+ Register result = ToRegister(instr->result());
+ ASSERT(!dividend.is(result));
+
+ if (divisor == 0) {
+ DeoptimizeIf(al, instr->environment());
+ return;
+ }
+
+ __ FlooringDiv(result, dividend, Abs(divisor));
+ __ add(result, result, Operand(dividend, LSR, 31));
+ __ mov(ip, Operand(Abs(divisor)));
+ __ smull(result, ip, result, ip);
+ __ sub(result, dividend, result, SetCC);
+
+ // Check for negative zero.
+ HMod* hmod = instr->hydrogen();
+ if (hmod->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ hmod->left()->CanBeNegative()) {
+ Label remainder_not_zero;
+ __ b(ne, &remainder_not_zero);
+ __ cmp(dividend, Operand::Zero());
+ DeoptimizeIf(lt, instr->environment());
+ __ bind(&remainder_not_zero);
+ }
+}
+
+
void LCodeGen::DoModI(LModI* instr) {
HMod* hmod = instr->hydrogen();
HValue* left = hmod->left();
}
-void LCodeGen::EmitSignedIntegerDivisionByConstant(
- Register result,
- Register dividend,
- int32_t divisor,
- Register remainder,
- Register scratch,
- LEnvironment* environment) {
- ASSERT(!AreAliased(dividend, scratch, ip));
- ASSERT(LChunkBuilder::HasMagicNumberForDivisor(divisor));
-
- uint32_t divisor_abs = abs(divisor);
-
- int32_t power_of_2_factor =
- CompilerIntrinsics::CountTrailingZeros(divisor_abs);
-
- switch (divisor_abs) {
- case 0:
- DeoptimizeIf(al, environment);
- return;
-
- case 1:
- if (divisor > 0) {
- __ Move(result, dividend);
- } else {
- __ rsb(result, dividend, Operand::Zero(), SetCC);
- DeoptimizeIf(vs, environment);
- }
- // Compute the remainder.
- __ mov(remainder, Operand::Zero());
- return;
-
- default:
- if (IsPowerOf2(divisor_abs)) {
- // Branch and condition free code for integer division by a power
- // of two.
- int32_t power = WhichPowerOf2(divisor_abs);
- if (power > 1) {
- __ mov(scratch, Operand(dividend, ASR, power - 1));
- }
- __ add(scratch, dividend, Operand(scratch, LSR, 32 - power));
- __ mov(result, Operand(scratch, ASR, power));
- // Negate if necessary.
- // We don't need to check for overflow because the case '-1' is
- // handled separately.
- if (divisor < 0) {
- ASSERT(divisor != -1);
- __ rsb(result, result, Operand::Zero());
- }
- // Compute the remainder.
- if (divisor > 0) {
- __ sub(remainder, dividend, Operand(result, LSL, power));
- } else {
- __ add(remainder, dividend, Operand(result, LSL, power));
- }
- return;
- } else {
- // Use magic numbers for a few specific divisors.
- // Details and proofs can be found in:
- // - Hacker's Delight, Henry S. Warren, Jr.
- // - The PowerPC Compiler Writer’s Guide
- // and probably many others.
- //
- // We handle
- // <divisor with magic numbers> * <power of 2>
- // but not
- // <divisor with magic numbers> * <other divisor with magic numbers>
- DivMagicNumbers magic_numbers =
- DivMagicNumberFor(divisor_abs >> power_of_2_factor);
- // Branch and condition free code for integer division by a power
- // of two.
- const int32_t M = magic_numbers.M;
- const int32_t s = magic_numbers.s + power_of_2_factor;
-
- __ mov(ip, Operand(M));
- __ smull(ip, scratch, dividend, ip);
- if (M < 0) {
- __ add(scratch, scratch, Operand(dividend));
- }
- if (s > 0) {
- __ mov(scratch, Operand(scratch, ASR, s));
- }
- __ add(result, scratch, Operand(dividend, LSR, 31));
- if (divisor < 0) __ rsb(result, result, Operand::Zero());
- // Compute the remainder.
- __ mov(ip, Operand(divisor));
- // This sequence could be replaced with 'mls' when
- // it gets implemented.
- __ mul(scratch, result, ip);
- __ sub(remainder, dividend, scratch);
- }
- }
-}
-
-
void LCodeGen::DoDivByPowerOf2I(LDivByPowerOf2I* instr) {
Register dividend = ToRegister(instr->dividend());
int32_t divisor = instr->divisor();
}
+void LCodeGen::DoDivByConstI(LDivByConstI* instr) {
+ Register dividend = ToRegister(instr->dividend());
+ int32_t divisor = instr->divisor();
+ Register result = ToRegister(instr->result());
+ ASSERT(!dividend.is(result));
+
+ if (divisor == 0) {
+ DeoptimizeIf(al, instr->environment());
+ return;
+ }
+
+ // Check for (0 / -x) that will produce negative zero.
+ HDiv* hdiv = instr->hydrogen();
+ if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ hdiv->left()->RangeCanInclude(0) && divisor < 0) {
+ __ cmp(dividend, Operand::Zero());
+ DeoptimizeIf(eq, instr->environment());
+ }
+
+ __ FlooringDiv(result, dividend, Abs(divisor));
+ __ add(result, result, Operand(dividend, LSR, 31));
+ if (divisor < 0) __ rsb(result, result, Operand::Zero());
+
+ if (!hdiv->CheckFlag(HInstruction::kAllUsesTruncatingToInt32)) {
+ __ mov(ip, Operand(divisor));
+ __ smull(scratch0(), ip, result, ip);
+ __ sub(scratch0(), scratch0(), dividend, SetCC);
+ DeoptimizeIf(ne, instr->environment());
+ }
+}
+
+
void LCodeGen::DoDivI(LDivI* instr) {
const Register left = ToRegister(instr->left());
const Register right = ToRegister(instr->right());
void LCodeGen::DoFlooringDivByConstI(LFlooringDivByConstI* instr) {
- Register left = ToRegister(instr->dividend());
- Register remainder = ToRegister(instr->temp());
- Register scratch = scratch0();
+ Register dividend = ToRegister(instr->dividend());
+ int32_t divisor = instr->divisor();
Register result = ToRegister(instr->result());
+ ASSERT(!dividend.is(result));
- if (!CpuFeatures::IsSupported(SUDIV)) {
- // If the CPU doesn't support sdiv instruction, we only optimize when we
- // have magic numbers for the divisor. The standard integer division routine
- // is usually slower than transitionning to VFP.
- ASSERT(instr->divisor()->IsConstantOperand());
- int32_t divisor = ToInteger32(LConstantOperand::cast(instr->divisor()));
- ASSERT(LChunkBuilder::HasMagicNumberForDivisor(divisor));
- if (divisor < 0) {
- __ cmp(left, Operand::Zero());
- DeoptimizeIf(eq, instr->environment());
- }
- EmitSignedIntegerDivisionByConstant(result,
- left,
- divisor,
- remainder,
- scratch,
- instr->environment());
- // We performed a truncating division. Correct the result if necessary.
- __ cmp(remainder, Operand::Zero());
- __ teq(remainder, Operand(divisor), ne);
- __ sub(result, result, Operand(1), LeaveCC, mi);
- } else {
- CpuFeatureScope scope(masm(), SUDIV);
- // TODO(svenpanne) We *statically* know the divisor, use that fact!
- Register right = ToRegister(instr->divisor());
+ if (divisor == 0) {
+ DeoptimizeIf(al, instr->environment());
+ return;
+ }
- // Check for x / 0.
- __ cmp(right, Operand::Zero());
+ // Check for (0 / -x) that will produce negative zero.
+ HMathFloorOfDiv* hdiv = instr->hydrogen();
+ if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ hdiv->left()->RangeCanInclude(0) && divisor < 0) {
+ __ cmp(dividend, Operand::Zero());
DeoptimizeIf(eq, instr->environment());
-
- // Check for (kMinInt / -1).
- if (instr->hydrogen()->CheckFlag(HValue::kCanOverflow)) {
- __ cmp(left, Operand(kMinInt));
- __ cmp(right, Operand(-1), eq);
- DeoptimizeIf(eq, instr->environment());
- }
-
- // Check for (0 / -x) that will produce negative zero.
- if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
- __ cmp(right, Operand::Zero());
- __ cmp(left, Operand::Zero(), mi);
- // "right" can't be null because the code would have already been
- // deoptimized. The Z flag is set only if (right < 0) and (left == 0).
- // In this case we need to deoptimize to produce a -0.
- DeoptimizeIf(eq, instr->environment());
- }
-
- Label done;
- __ sdiv(result, left, right);
- // If both operands have the same sign then we are done.
- __ eor(remainder, left, Operand(right), SetCC);
- __ b(pl, &done);
-
- // Check if the result needs to be corrected.
- __ mls(remainder, result, right, left);
- __ cmp(remainder, Operand::Zero());
- __ sub(result, result, Operand(1), LeaveCC, ne);
-
- __ bind(&done);
}
+
+ __ FlooringDiv(result, dividend, divisor);
}
int* offset,
AllocationSiteMode mode);
- // Emit optimized code for integer division.
- // Inputs are signed.
- // All registers are clobbered.
- // If 'remainder' is no_reg, it is not computed.
- void EmitSignedIntegerDivisionByConstant(Register result,
- Register dividend,
- int32_t divisor,
- Register remainder,
- Register scratch,
- LEnvironment* environment);
-
void EnsureSpaceForLazyDeopt(int space_needed) V8_OVERRIDE;
void DoLoadKeyedExternalArray(LLoadKeyed* instr);
void DoLoadKeyedFixedDoubleArray(LLoadKeyed* instr);
}
+void MacroAssembler::FlooringDiv(Register result,
+ Register dividend,
+ int32_t divisor) {
+ ASSERT(!dividend.is(result));
+ ASSERT(!dividend.is(ip));
+ ASSERT(!result.is(ip));
+ MultiplierAndShift ms(divisor);
+ mov(ip, Operand(ms.multiplier()));
+ smull(ip, result, dividend, ip);
+ if (divisor > 0 && ms.multiplier() < 0) {
+ add(result, result, Operand(dividend));
+ }
+ if (divisor < 0 && ms.multiplier() > 0) {
+ sub(result, result, Operand(dividend));
+ }
+ if (ms.shift() > 0) mov(result, Operand(result, ASR, ms.shift()));
+}
+
+
} } // namespace v8::internal
#endif // V8_TARGET_ARCH_ARM
}
+ // Emit code for a flooring division by a constant. The dividend register is
+ // unchanged and ip gets clobbered. Dividend and result must be different.
+ void FlooringDiv(Register result, Register dividend, int32_t divisor);
+
// ---------------------------------------------------------------------------
// StatsCounter support
return written;
}
+
+MultiplierAndShift::MultiplierAndShift(int32_t d) {
+ ASSERT(d <= -2 || 2 <= d);
+ const uint32_t two31 = 0x80000000;
+ uint32_t ad = Abs(d);
+ uint32_t t = two31 + (uint32_t(d) >> 31);
+ uint32_t anc = t - 1 - t % ad; // Absolute value of nc.
+ int32_t p = 31; // Init. p.
+ uint32_t q1 = two31 / anc; // Init. q1 = 2**p/|nc|.
+ uint32_t r1 = two31 - q1 * anc; // Init. r1 = rem(2**p, |nc|).
+ uint32_t q2 = two31 / ad; // Init. q2 = 2**p/|d|.
+ uint32_t r2 = two31 - q2 * ad; // Init. r2 = rem(2**p, |d|).
+ uint32_t delta;
+ do {
+ p++;
+ q1 *= 2; // Update q1 = 2**p/|nc|.
+ r1 *= 2; // Update r1 = rem(2**p, |nc|).
+ if (r1 >= anc) { // Must be an unsigned comparison here.
+ q1++;
+ r1 = r1 - anc;
+ }
+ q2 *= 2; // Update q2 = 2**p/|d|.
+ r2 *= 2; // Update r2 = rem(2**p, |d|).
+ if (r2 >= ad) { // Must be an unsigned comparison here.
+ q2++;
+ r2 = r2 - ad;
+ }
+ delta = ad - r2;
+ } while (q1 < delta || (q1 == delta && r1 == 0));
+ int32_t mul = static_cast<int32_t>(q2 + 1);
+ multiplier_ = (d < 0) ? -mul : mul;
+ shift_ = p - 32;
+}
+
} } // namespace v8::internal
virtual void AfterCall() const { }
};
+
+// The multiplier and shift for signed division via multiplication, see Warren's
+// "Hacker's Delight", chapter 10.
+class MultiplierAndShift {
+ public:
+ explicit MultiplierAndShift(int32_t d);
+ int32_t multiplier() const { return multiplier_; }
+ int32_t shift() const { return shift_; }
+
+ private:
+ int32_t multiplier_;
+ int32_t shift_;
+};
+
+
} } // namespace v8::internal
#endif // V8_ASSEMBLER_H_
}
+void LCodeGen::DoModByConstI(LModByConstI* instr) {
+ Register dividend = ToRegister(instr->dividend());
+ int32_t divisor = instr->divisor();
+ ASSERT(ToRegister(instr->result()).is(eax));
+
+ if (divisor == 0) {
+ DeoptimizeIf(no_condition, instr->environment());
+ return;
+ }
+
+ __ FlooringDiv(dividend, Abs(divisor));
+ __ mov(eax, dividend);
+ __ shr(eax, 31);
+ __ add(edx, eax);
+ __ imul(edx, edx, Abs(divisor));
+ __ mov(eax, dividend);
+ __ sub(eax, edx);
+
+ // Check for negative zero.
+ HMod* hmod = instr->hydrogen();
+ if (hmod->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ hmod->left()->CanBeNegative()) {
+ Label remainder_not_zero;
+ __ j(not_zero, &remainder_not_zero, Label::kNear);
+ __ cmp(dividend, Immediate(0));
+ DeoptimizeIf(less, instr->environment());
+ __ bind(&remainder_not_zero);
+ }
+}
+
+
void LCodeGen::DoModI(LModI* instr) {
HMod* hmod = instr->hydrogen();
HValue* left = hmod->left();
}
+void LCodeGen::DoDivByConstI(LDivByConstI* instr) {
+ Register dividend = ToRegister(instr->dividend());
+ int32_t divisor = instr->divisor();
+ ASSERT(ToRegister(instr->result()).is(edx));
+
+ if (divisor == 0) {
+ DeoptimizeIf(no_condition, instr->environment());
+ return;
+ }
+
+ // Check for (0 / -x) that will produce negative zero.
+ HDiv* hdiv = instr->hydrogen();
+ if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ hdiv->left()->RangeCanInclude(0) && divisor < 0) {
+ __ test(dividend, dividend);
+ DeoptimizeIf(zero, instr->environment());
+ }
+
+ __ FlooringDiv(dividend, Abs(divisor));
+ __ mov(eax, dividend);
+ __ shr(eax, 31);
+ __ add(edx, eax);
+ if (divisor < 0) __ neg(edx);
+
+ if (!hdiv->CheckFlag(HInstruction::kAllUsesTruncatingToInt32)) {
+ __ mov(eax, edx);
+ __ imul(eax, eax, divisor);
+ __ sub(eax, dividend);
+ DeoptimizeIf(not_equal, instr->environment());
+ }
+}
+
+
void LCodeGen::DoDivI(LDivI* instr) {
Register dividend = ToRegister(instr->left());
Register divisor = ToRegister(instr->right());
void LCodeGen::DoFlooringDivByConstI(LFlooringDivByConstI* instr) {
Register dividend = ToRegister(instr->dividend());
int32_t divisor = instr->divisor();
- Register scratch = ToRegister(instr->temp());
- ASSERT(ToRegister(instr->dividend()).is(eax));
ASSERT(ToRegister(instr->result()).is(edx));
if (divisor == 0) {
return;
}
- // Find b which: 2^b < divisor_abs < 2^(b+1).
- uint32_t divisor_abs = abs(divisor);
- unsigned b = 31 - CompilerIntrinsics::CountLeadingZeros(divisor_abs);
- unsigned shift = 32 + b; // Precision +1bit (effectively).
- double multiplier_f =
- static_cast<double>(static_cast<uint64_t>(1) << shift) / divisor_abs;
- int64_t multiplier;
- if (multiplier_f - std::floor(multiplier_f) < 0.5) {
- multiplier = static_cast<int64_t>(std::floor(multiplier_f));
- } else {
- multiplier = static_cast<int64_t>(std::floor(multiplier_f)) + 1;
- }
- // The multiplier is a uint32.
- ASSERT(multiplier > 0 &&
- multiplier < (static_cast<int64_t>(1) << 32));
- __ mov(scratch, dividend);
- if (divisor < 0 &&
- instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
+ // Check for (0 / -x) that will produce negative zero.
+ HMathFloorOfDiv* hdiv = instr->hydrogen();
+ if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ hdiv->left()->RangeCanInclude(0) && divisor < 0) {
__ test(dividend, dividend);
DeoptimizeIf(zero, instr->environment());
}
- __ mov(edx, static_cast<int32_t>(multiplier));
- __ imul(edx);
- if (static_cast<int32_t>(multiplier) < 0) {
- __ add(edx, scratch);
- }
- Register reg_lo = eax;
- Register reg_byte_scratch = scratch;
- if (!reg_byte_scratch.is_byte_register()) {
- __ xchg(reg_lo, reg_byte_scratch);
- reg_lo = scratch;
- reg_byte_scratch = eax;
- }
- if (divisor < 0) {
- __ xor_(reg_byte_scratch, reg_byte_scratch);
- __ cmp(reg_lo, 0x40000000);
- __ setcc(above, reg_byte_scratch);
- __ neg(edx);
- __ sub(edx, reg_byte_scratch);
- } else {
- __ xor_(reg_byte_scratch, reg_byte_scratch);
- __ cmp(reg_lo, 0xC0000000);
- __ setcc(above_equal, reg_byte_scratch);
- __ add(edx, reg_byte_scratch);
- }
- __ sar(edx, shift - 32);
+
+ __ FlooringDiv(dividend, divisor);
}
}
+LInstruction* LChunkBuilder::DoDivByConstI(HDiv* instr) {
+ ASSERT(instr->representation().IsInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
+ LOperand* dividend = UseRegister(instr->left());
+ int32_t divisor = instr->right()->GetInteger32Constant();
+ LOperand* temp1 = FixedTemp(eax);
+ LOperand* temp2 = FixedTemp(edx);
+ LInstruction* result =
+ DefineFixed(
+ new(zone()) LDivByConstI(dividend, divisor, temp1, temp2), edx);
+ bool can_deopt =
+ divisor == 0 ||
+ (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ instr->left()->RangeCanInclude(0) && divisor < 0) ||
+ !instr->CheckFlag(HInstruction::kAllUsesTruncatingToInt32);
+ return can_deopt ? AssignEnvironment(result) : result;
+}
+
+
LInstruction* LChunkBuilder::DoDivI(HBinaryOperation* instr) {
ASSERT(instr->representation().IsSmiOrInteger32());
ASSERT(instr->left()->representation().Equals(instr->representation()));
LOperand* dividend = UseFixed(instr->left(), eax);
LOperand* divisor = UseRegister(instr->right());
LOperand* temp = FixedTemp(edx);
- LDivI* result = new(zone()) LDivI(dividend, divisor, temp);
- return AssignEnvironment(DefineFixed(result, eax));
+ LInstruction* result =
+ DefineFixed(new(zone()) LDivI(dividend, divisor, temp), eax);
+ return AssignEnvironment(result);
}
LInstruction* LChunkBuilder::DoDiv(HDiv* instr) {
if (instr->representation().IsSmiOrInteger32()) {
- return instr->RightIsPowerOf2() ? DoDivByPowerOf2I(instr) : DoDivI(instr);
+ if (instr->RightIsPowerOf2()) {
+ return DoDivByPowerOf2I(instr);
+ } else if (instr->right()->IsConstant()) {
+ return DoDivByConstI(instr);
+ } else {
+ return DoDivI(instr);
+ }
} else if (instr->representation().IsDouble()) {
return DoArithmeticD(Token::DIV, instr);
} else {
LInstruction* LChunkBuilder::DoFlooringDivByConstI(HMathFloorOfDiv* instr) {
- LOperand* dividend = UseFixed(instr->left(), eax);
+ ASSERT(instr->representation().IsInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
+ LOperand* dividend = UseRegister(instr->left());
int32_t divisor = instr->right()->GetInteger32Constant();
- LOperand* temp = TempRegister();
+ LOperand* temp1 = FixedTemp(eax);
+ LOperand* temp2 = FixedTemp(edx);
LInstruction* result =
- DefineFixed(
- new(zone()) LFlooringDivByConstI(dividend, divisor, temp), edx);
- bool can_deopt = divisor <= 0;
+ DefineFixed(new(zone()) LFlooringDivByConstI(dividend,
+ divisor,
+ temp1,
+ temp2),
+ edx);
+ bool can_deopt =
+ divisor == 0 ||
+ (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ instr->left()->RangeCanInclude(0) && divisor < 0);
return can_deopt ? AssignEnvironment(result) : result;
}
}
+LInstruction* LChunkBuilder::DoModByConstI(HMod* instr) {
+ ASSERT(instr->representation().IsSmiOrInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
+ LOperand* dividend = UseRegister(instr->left());
+ int32_t divisor = instr->right()->GetInteger32Constant();
+ LOperand* temp1 = FixedTemp(eax);
+ LOperand* temp2 = FixedTemp(edx);
+ LInstruction* result =
+ DefineFixed(
+ new(zone()) LModByConstI(dividend, divisor, temp1, temp2), eax);
+ bool can_deopt =
+ divisor == 0 ||
+ (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ instr->left()->CanBeNegative());
+ return can_deopt ? AssignEnvironment(result) : result;
+}
+
+
LInstruction* LChunkBuilder::DoModI(HMod* instr) {
ASSERT(instr->representation().IsSmiOrInteger32());
ASSERT(instr->left()->representation().Equals(instr->representation()));
LInstruction* LChunkBuilder::DoMod(HMod* instr) {
if (instr->representation().IsSmiOrInteger32()) {
- return instr->RightIsPowerOf2() ? DoModByPowerOf2I(instr) : DoModI(instr);
+ if (instr->RightIsPowerOf2()) {
+ return DoModByPowerOf2I(instr);
+ } else if (instr->right()->IsConstant()) {
+ return DoModByConstI(instr);
+ } else {
+ return DoModI(instr);
+ }
} else if (instr->representation().IsDouble()) {
return DoArithmeticD(Token::MOD, instr);
} else {
V(DebugBreak) \
V(DeclareGlobals) \
V(Deoptimize) \
+ V(DivByConstI) \
V(DivByPowerOf2I) \
V(DivI) \
V(DoubleBits) \
V(MathPowHalf) \
V(MathRound) \
V(MathSqrt) \
+ V(ModByConstI) \
V(ModByPowerOf2I) \
V(ModI) \
V(MulI) \
};
+class LModByConstI V8_FINAL : public LTemplateInstruction<1, 1, 2> {
+ public:
+ LModByConstI(LOperand* dividend,
+ int32_t divisor,
+ LOperand* temp1,
+ LOperand* temp2) {
+ inputs_[0] = dividend;
+ divisor_ = divisor;
+ temps_[0] = temp1;
+ temps_[1] = temp2;
+ }
+
+ LOperand* dividend() { return inputs_[0]; }
+ int32_t divisor() const { return divisor_; }
+ LOperand* temp1() { return temps_[0]; }
+ LOperand* temp2() { return temps_[1]; }
+
+ DECLARE_CONCRETE_INSTRUCTION(ModByConstI, "mod-by-const-i")
+ DECLARE_HYDROGEN_ACCESSOR(Mod)
+
+ private:
+ int32_t divisor_;
+};
+
+
class LModI V8_FINAL : public LTemplateInstruction<1, 2, 1> {
public:
LModI(LOperand* left, LOperand* right, LOperand* temp) {
};
+class LDivByConstI V8_FINAL : public LTemplateInstruction<1, 1, 2> {
+ public:
+ LDivByConstI(LOperand* dividend,
+ int32_t divisor,
+ LOperand* temp1,
+ LOperand* temp2) {
+ inputs_[0] = dividend;
+ divisor_ = divisor;
+ temps_[0] = temp1;
+ temps_[1] = temp2;
+ }
+
+ LOperand* dividend() { return inputs_[0]; }
+ int32_t divisor() const { return divisor_; }
+ LOperand* temp1() { return temps_[0]; }
+ LOperand* temp2() { return temps_[1]; }
+
+ DECLARE_CONCRETE_INSTRUCTION(DivByConstI, "div-by-const-i")
+ DECLARE_HYDROGEN_ACCESSOR(Div)
+
+ private:
+ int32_t divisor_;
+};
+
+
class LDivI V8_FINAL : public LTemplateInstruction<1, 2, 1> {
public:
LDivI(LOperand* left, LOperand* right, LOperand* temp) {
};
-class LFlooringDivByConstI V8_FINAL : public LTemplateInstruction<1, 1, 1> {
+class LFlooringDivByConstI V8_FINAL : public LTemplateInstruction<1, 1, 2> {
public:
- LFlooringDivByConstI(LOperand* dividend, int32_t divisor, LOperand* temp) {
+ LFlooringDivByConstI(LOperand* dividend,
+ int32_t divisor,
+ LOperand* temp1,
+ LOperand* temp2) {
inputs_[0] = dividend;
divisor_ = divisor;
- temps_[0] = temp;
+ temps_[0] = temp1;
+ temps_[1] = temp2;
}
LOperand* dividend() { return inputs_[0]; }
int32_t divisor() const { return divisor_; }
- LOperand* temp() { return temps_[0]; }
+ LOperand* temp1() { return temps_[0]; }
+ LOperand* temp2() { return temps_[1]; }
DECLARE_CONCRETE_INSTRUCTION(FlooringDivByConstI, "flooring-div-by-const-i")
DECLARE_HYDROGEN_ACCESSOR(MathFloorOfDiv)
LInstruction* DoMathPowHalf(HUnaryMathOperation* instr);
LInstruction* DoMathClz32(HUnaryMathOperation* instr);
LInstruction* DoDivByPowerOf2I(HDiv* instr);
+ LInstruction* DoDivByConstI(HDiv* instr);
LInstruction* DoDivI(HBinaryOperation* instr);
LInstruction* DoModByPowerOf2I(HMod* instr);
+ LInstruction* DoModByConstI(HMod* instr);
LInstruction* DoModI(HMod* instr);
LInstruction* DoFlooringDivByPowerOf2I(HMathFloorOfDiv* instr);
LInstruction* DoFlooringDivByConstI(HMathFloorOfDiv* instr);
j(not_equal, &loop_again);
}
+
+void MacroAssembler::FlooringDiv(Register dividend, int32_t divisor) {
+ ASSERT(!dividend.is(eax));
+ ASSERT(!dividend.is(edx));
+ MultiplierAndShift ms(divisor);
+ mov(eax, Immediate(ms.multiplier()));
+ imul(dividend);
+ if (divisor > 0 && ms.multiplier() < 0) add(edx, dividend);
+ if (divisor < 0 && ms.multiplier() > 0) sub(edx, dividend);
+ if (ms.shift() > 0) sar(edx, ms.shift());
+}
+
+
} } // namespace v8::internal
#endif // V8_TARGET_ARCH_IA32
// Insert code to verify that the x87 stack has the specified depth (0-7)
void VerifyX87StackDepth(uint32_t depth);
+ // Emit code for a flooring division by a constant. The dividend register is
+ // unchanged, the result is in edx, and eax gets clobbered.
+ void FlooringDiv(Register dividend, int32_t divisor);
+
// ---------------------------------------------------------------------------
// StatsCounter support
}
-const DivMagicNumbers DivMagicNumberFor(int32_t divisor) {
- switch (divisor) {
- case 3: return DivMagicNumberFor3;
- case 5: return DivMagicNumberFor5;
- case 7: return DivMagicNumberFor7;
- case 9: return DivMagicNumberFor9;
- case 11: return DivMagicNumberFor11;
- case 25: return DivMagicNumberFor25;
- case 125: return DivMagicNumberFor125;
- case 625: return DivMagicNumberFor625;
- default: return InvalidDivMagicNumber;
- }
-}
-
} } // namespace v8::internal
}
-// Magic numbers for integer division.
-// These are kind of 2's complement reciprocal of the divisors.
-// Details and proofs can be found in:
-// - Hacker's Delight, Henry S. Warren, Jr.
-// - The PowerPC Compiler Writer’s Guide
-// and probably many others.
-// See details in the implementation of the algorithm in
-// lithium-codegen-arm.cc : LCodeGen::TryEmitSignedIntegerDivisionByConstant().
-struct DivMagicNumbers {
- unsigned M;
- unsigned s;
-};
-
-const DivMagicNumbers InvalidDivMagicNumber= {0, 0};
-const DivMagicNumbers DivMagicNumberFor3 = {0x55555556, 0};
-const DivMagicNumbers DivMagicNumberFor5 = {0x66666667, 1};
-const DivMagicNumbers DivMagicNumberFor7 = {0x92492493, 2};
-const DivMagicNumbers DivMagicNumberFor9 = {0x38e38e39, 1};
-const DivMagicNumbers DivMagicNumberFor11 = {0x2e8ba2e9, 1};
-const DivMagicNumbers DivMagicNumberFor25 = {0x51eb851f, 3};
-const DivMagicNumbers DivMagicNumberFor125 = {0x10624dd3, 3};
-const DivMagicNumbers DivMagicNumberFor625 = {0x68db8bad, 8};
-
-const DivMagicNumbers DivMagicNumberFor(int32_t divisor);
-
-
// The C++ standard leaves the semantics of '>>' undefined for
// negative signed operands. Most implementations do the right thing,
// though.
}
+void Assembler::imull(Register src) {
+ EnsureSpace ensure_space(this);
+ emit_optional_rex_32(src);
+ emit(0xF7);
+ emit_modrm(0x5, src);
+}
+
+
void Assembler::imull(Register dst, Register src) {
EnsureSpace ensure_space(this);
emit_optional_rex_32(dst, src);
void imul(Register dst, const Operand& src); // dst = dst * src.
void imul(Register dst, Register src, Immediate imm); // dst = src * imm.
// Signed 32-bit multiply instructions.
+ void imull(Register src); // edx:eax = eax * src.
void imull(Register dst, Register src); // dst = dst * src.
void imull(Register dst, const Operand& src); // dst = dst * src.
void imull(Register dst, Register src, Immediate imm); // dst = src * imm.
}
+void LCodeGen::DoModByConstI(LModByConstI* instr) {
+ Register dividend = ToRegister(instr->dividend());
+ int32_t divisor = instr->divisor();
+ ASSERT(ToRegister(instr->result()).is(rax));
+
+ if (divisor == 0) {
+ DeoptimizeIf(no_condition, instr->environment());
+ return;
+ }
+
+ __ FlooringDiv(dividend, Abs(divisor));
+ __ movl(rax, dividend);
+ __ shrl(rax, Immediate(31));
+ __ addl(rdx, rax);
+ __ imull(rdx, rdx, Immediate(Abs(divisor)));
+ __ movl(rax, dividend);
+ __ subl(rax, rdx);
+
+ // Check for negative zero.
+ HMod* hmod = instr->hydrogen();
+ if (hmod->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ hmod->left()->CanBeNegative()) {
+ Label remainder_not_zero;
+ __ j(not_zero, &remainder_not_zero, Label::kNear);
+ __ cmpl(dividend, Immediate(0));
+ DeoptimizeIf(less, instr->environment());
+ __ bind(&remainder_not_zero);
+ }
+}
+
+
void LCodeGen::DoModI(LModI* instr) {
if (instr->hydrogen()->RightIsPowerOf2()) {
return DoModByPowerOf2I(reinterpret_cast<LModByPowerOf2I*>(instr));
void LCodeGen::DoFlooringDivByConstI(LFlooringDivByConstI* instr) {
Register dividend = ToRegister(instr->dividend());
int32_t divisor = instr->divisor();
- Register temp = ToRegister(instr->temp());
- Register result = ToRegister(instr->result());
+ ASSERT(ToRegister(instr->result()).is(rdx));
if (divisor == 0) {
DeoptimizeIf(no_condition, instr->environment());
return;
}
- // Find b which: 2^b < divisor_abs < 2^(b+1).
- uint32_t divisor_abs = abs(divisor);
- unsigned b = 31 - CompilerIntrinsics::CountLeadingZeros(divisor_abs);
- unsigned shift = 32 + b; // Precision +1bit (effectively).
- double multiplier_f =
- static_cast<double>(static_cast<uint64_t>(1) << shift) / divisor_abs;
- int64_t multiplier;
- if (multiplier_f - std::floor(multiplier_f) < 0.5) {
- multiplier = static_cast<int64_t>(std::floor(multiplier_f));
- } else {
- multiplier = static_cast<int64_t>(std::floor(multiplier_f)) + 1;
- }
- // The multiplier is a uint32.
- ASSERT(multiplier > 0 &&
- multiplier < (static_cast<int64_t>(1) << 32));
- // The multiply is int64, so sign-extend to r64.
- __ movsxlq(temp, dividend);
- if (divisor < 0 &&
- instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
- __ neg(temp);
+ // Check for (0 / -x) that will produce negative zero.
+ HMathFloorOfDiv* hdiv = instr->hydrogen();
+ if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ hdiv->left()->RangeCanInclude(0) && divisor < 0) {
+ __ testl(dividend, dividend);
DeoptimizeIf(zero, instr->environment());
}
- __ Set(result, multiplier);
- // Result just fit in r64, because it's int32 * uint32.
- __ imul(result, temp);
- __ addq(result, Immediate(1 << 30));
- __ sar(result, Immediate(shift));
+ __ FlooringDiv(dividend, divisor);
}
}
+void LCodeGen::DoDivByConstI(LDivByConstI* instr) {
+ Register dividend = ToRegister(instr->dividend());
+ int32_t divisor = instr->divisor();
+ ASSERT(ToRegister(instr->result()).is(rdx));
+
+ if (divisor == 0) {
+ DeoptimizeIf(no_condition, instr->environment());
+ return;
+ }
+
+ // Check for (0 / -x) that will produce negative zero.
+ HDiv* hdiv = instr->hydrogen();
+ if (hdiv->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ hdiv->left()->RangeCanInclude(0) && divisor < 0) {
+ __ testl(dividend, dividend);
+ DeoptimizeIf(zero, instr->environment());
+ }
+
+ __ FlooringDiv(dividend, Abs(divisor));
+ __ movl(rax, dividend);
+ __ shrl(rax, Immediate(31));
+ __ addl(rdx, rax);
+ if (divisor < 0) __ neg(rdx);
+
+ if (!hdiv->CheckFlag(HInstruction::kAllUsesTruncatingToInt32)) {
+ __ movl(rax, rdx);
+ __ imull(rax, rax, Immediate(divisor));
+ __ subl(rax, dividend);
+ DeoptimizeIf(not_equal, instr->environment());
+ }
+}
+
+
void LCodeGen::DoDivI(LDivI* instr) {
Register dividend = ToRegister(instr->left());
Register divisor = ToRegister(instr->right());
}
+LInstruction* LChunkBuilder::DoDivByConstI(HDiv* instr) {
+ ASSERT(instr->representation().IsInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
+ LOperand* dividend = UseRegister(instr->left());
+ int32_t divisor = instr->right()->GetInteger32Constant();
+ LOperand* temp1 = FixedTemp(rax);
+ LOperand* temp2 = FixedTemp(rdx);
+ LInstruction* result =
+ DefineFixed(
+ new(zone()) LDivByConstI(dividend, divisor, temp1, temp2), rdx);
+ bool can_deopt =
+ divisor == 0 ||
+ (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ instr->left()->RangeCanInclude(0) && divisor < 0) ||
+ !instr->CheckFlag(HInstruction::kAllUsesTruncatingToInt32);
+ return can_deopt ? AssignEnvironment(result) : result;
+}
+
+
LInstruction* LChunkBuilder::DoDivI(HBinaryOperation* instr) {
ASSERT(instr->representation().IsSmiOrInteger32());
ASSERT(instr->left()->representation().Equals(instr->representation()));
LInstruction* LChunkBuilder::DoDiv(HDiv* instr) {
if (instr->representation().IsSmiOrInteger32()) {
- return instr->RightIsPowerOf2() ? DoDivByPowerOf2I(instr) : DoDivI(instr);
+ if (instr->RightIsPowerOf2()) {
+ return DoDivByPowerOf2I(instr);
+ } else if (instr->right()->IsConstant()) {
+ return DoDivByConstI(instr);
+ } else {
+ return DoDivI(instr);
+ }
} else if (instr->representation().IsDouble()) {
return DoArithmeticD(Token::DIV, instr);
} else {
LInstruction* LChunkBuilder::DoFlooringDivByConstI(HMathFloorOfDiv* instr) {
- LOperand* dividend = UseRegisterAtStart(instr->left());
+ ASSERT(instr->representation().IsInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
+ LOperand* dividend = UseRegister(instr->left());
int32_t divisor = instr->right()->GetInteger32Constant();
- LOperand* temp = TempRegister();
+ LOperand* temp1 = FixedTemp(rax);
+ LOperand* temp2 = FixedTemp(rdx);
LInstruction* result =
- DefineAsRegister(
- new(zone()) LFlooringDivByConstI(dividend, divisor, temp));
- bool can_deopt = divisor <= 0;
+ DefineFixed(new(zone()) LFlooringDivByConstI(dividend,
+ divisor,
+ temp1,
+ temp2),
+ rdx);
+ bool can_deopt =
+ divisor == 0 ||
+ (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ instr->left()->RangeCanInclude(0) && divisor < 0);
return can_deopt ? AssignEnvironment(result) : result;
}
}
+LInstruction* LChunkBuilder::DoModByConstI(HMod* instr) {
+ ASSERT(instr->representation().IsSmiOrInteger32());
+ ASSERT(instr->left()->representation().Equals(instr->representation()));
+ ASSERT(instr->right()->representation().Equals(instr->representation()));
+ LOperand* dividend = UseRegister(instr->left());
+ int32_t divisor = instr->right()->GetInteger32Constant();
+ LOperand* temp1 = FixedTemp(rax);
+ LOperand* temp2 = FixedTemp(rdx);
+ LInstruction* result =
+ DefineFixed(
+ new(zone()) LModByConstI(dividend, divisor, temp1, temp2), rax);
+ bool can_deopt =
+ divisor == 0 ||
+ (instr->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ instr->left()->CanBeNegative());
+ return can_deopt ? AssignEnvironment(result) : result;
+}
+
+
LInstruction* LChunkBuilder::DoModI(HMod* instr) {
ASSERT(instr->representation().IsSmiOrInteger32());
ASSERT(instr->left()->representation().Equals(instr->representation()));
LInstruction* LChunkBuilder::DoMod(HMod* instr) {
if (instr->representation().IsSmiOrInteger32()) {
- return instr->RightIsPowerOf2() ? DoModByPowerOf2I(instr) : DoModI(instr);
+ if (instr->RightIsPowerOf2()) {
+ return DoModByPowerOf2I(instr);
+ } else if (instr->right()->IsConstant()) {
+ return DoModByConstI(instr);
+ } else {
+ return DoModI(instr);
+ }
} else if (instr->representation().IsDouble()) {
return DoArithmeticD(Token::MOD, instr);
} else {
V(DebugBreak) \
V(DeclareGlobals) \
V(Deoptimize) \
+ V(DivByConstI) \
V(DivByPowerOf2I) \
V(DivI) \
V(DoubleBits) \
V(MathPowHalf) \
V(MathRound) \
V(MathSqrt) \
+ V(ModByConstI) \
V(ModByPowerOf2I) \
V(ModI) \
V(MulI) \
};
+class LModByConstI V8_FINAL : public LTemplateInstruction<1, 1, 2> {
+ public:
+ LModByConstI(LOperand* dividend,
+ int32_t divisor,
+ LOperand* temp1,
+ LOperand* temp2) {
+ inputs_[0] = dividend;
+ divisor_ = divisor;
+ temps_[0] = temp1;
+ temps_[1] = temp2;
+ }
+
+ LOperand* dividend() { return inputs_[0]; }
+ int32_t divisor() const { return divisor_; }
+ LOperand* temp1() { return temps_[0]; }
+ LOperand* temp2() { return temps_[1]; }
+
+ DECLARE_CONCRETE_INSTRUCTION(ModByConstI, "mod-by-const-i")
+ DECLARE_HYDROGEN_ACCESSOR(Mod)
+
+ private:
+ int32_t divisor_;
+};
+
+
class LModI V8_FINAL : public LTemplateInstruction<1, 2, 1> {
public:
LModI(LOperand* left, LOperand* right, LOperand* temp) {
};
+class LDivByConstI V8_FINAL : public LTemplateInstruction<1, 1, 2> {
+ public:
+ LDivByConstI(LOperand* dividend,
+ int32_t divisor,
+ LOperand* temp1,
+ LOperand* temp2) {
+ inputs_[0] = dividend;
+ divisor_ = divisor;
+ temps_[0] = temp1;
+ temps_[1] = temp2;
+ }
+
+ LOperand* dividend() { return inputs_[0]; }
+ int32_t divisor() const { return divisor_; }
+ LOperand* temp1() { return temps_[0]; }
+ LOperand* temp2() { return temps_[1]; }
+
+ DECLARE_CONCRETE_INSTRUCTION(DivByConstI, "div-by-const-i")
+ DECLARE_HYDROGEN_ACCESSOR(Div)
+
+ private:
+ int32_t divisor_;
+};
+
+
class LDivI V8_FINAL : public LTemplateInstruction<1, 2, 1> {
public:
LDivI(LOperand* left, LOperand* right, LOperand* temp) {
};
-class LFlooringDivByConstI V8_FINAL : public LTemplateInstruction<1, 1, 1> {
+class LFlooringDivByConstI V8_FINAL : public LTemplateInstruction<1, 1, 2> {
public:
- LFlooringDivByConstI(LOperand* dividend, int32_t divisor, LOperand* temp) {
+ LFlooringDivByConstI(LOperand* dividend,
+ int32_t divisor,
+ LOperand* temp1,
+ LOperand* temp2) {
inputs_[0] = dividend;
divisor_ = divisor;
- temps_[0] = temp;
+ temps_[0] = temp1;
+ temps_[1] = temp2;
}
LOperand* dividend() { return inputs_[0]; }
int32_t divisor() const { return divisor_; }
- LOperand* temp() { return temps_[0]; }
+ LOperand* temp1() { return temps_[0]; }
+ LOperand* temp2() { return temps_[0]; }
DECLARE_CONCRETE_INSTRUCTION(FlooringDivByConstI, "flooring-div-by-const-i")
DECLARE_HYDROGEN_ACCESSOR(MathFloorOfDiv)
LInstruction* DoMathPowHalf(HUnaryMathOperation* instr);
LInstruction* DoMathClz32(HUnaryMathOperation* instr);
LInstruction* DoDivByPowerOf2I(HDiv* instr);
+ LInstruction* DoDivByConstI(HDiv* instr);
LInstruction* DoDivI(HBinaryOperation* instr);
LInstruction* DoModByPowerOf2I(HMod* instr);
+ LInstruction* DoModByConstI(HMod* instr);
LInstruction* DoModI(HMod* instr);
LInstruction* DoFlooringDivByPowerOf2I(HMathFloorOfDiv* instr);
LInstruction* DoFlooringDivByConstI(HMathFloorOfDiv* instr);
}
+void MacroAssembler::FlooringDiv(Register dividend, int32_t divisor) {
+ ASSERT(!dividend.is(rax));
+ ASSERT(!dividend.is(rdx));
+ MultiplierAndShift ms(divisor);
+ movl(rax, Immediate(ms.multiplier()));
+ imull(dividend);
+ if (divisor > 0 && ms.multiplier() < 0) addl(rdx, dividend);
+ if (divisor < 0 && ms.multiplier() > 0) subl(rdx, dividend);
+ if (ms.shift() > 0) sarl(rdx, Immediate(ms.shift()));
+}
+
+
} } // namespace v8::internal
#endif // V8_TARGET_ARCH_X64
Register filler);
+ // Emit code for a flooring division by a constant. The dividend register is
+ // unchanged, the result is in rdx, and rax gets clobbered.
+ void FlooringDiv(Register dividend, int32_t divisor);
+
// ---------------------------------------------------------------------------
// StatsCounter support
test_div_deopt_minus_zero_v();
test_div_deopt_overflow_v();
test_div_deopt_div_by_zero_v();
+
+
+// Test for flooring division with negative dividend.
+function flooring_div_by_3(y) {
+ return Math.floor(y / 3);
+}
+
+assertEquals(-1, flooring_div_by_3(-2));
+assertEquals(-1, flooring_div_by_3(-2));
+%OptimizeFunctionOnNextCall(flooring_div_by_3);
+assertEquals(-1, flooring_div_by_3(-2));
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