diff options
Diffstat (limited to 'compiler/optimizing/code_generator_arm.cc')
| -rw-r--r-- | compiler/optimizing/code_generator_arm.cc | 615 |
1 files changed, 121 insertions, 494 deletions
diff --git a/compiler/optimizing/code_generator_arm.cc b/compiler/optimizing/code_generator_arm.cc index 1990e8f67d..f5f40fc686 100644 --- a/compiler/optimizing/code_generator_arm.cc +++ b/compiler/optimizing/code_generator_arm.cc @@ -1652,34 +1652,6 @@ static void GenerateVcmp(HInstruction* instruction, CodeGeneratorARM* codegen) { } } -static int64_t AdjustConstantForCondition(int64_t value, - IfCondition* condition, - IfCondition* opposite) { - if (value == 1) { - if (*condition == kCondB) { - value = 0; - *condition = kCondEQ; - *opposite = kCondNE; - } else if (*condition == kCondAE) { - value = 0; - *condition = kCondNE; - *opposite = kCondEQ; - } - } else if (value == -1) { - if (*condition == kCondGT) { - value = 0; - *condition = kCondGE; - *opposite = kCondLT; - } else if (*condition == kCondLE) { - value = 0; - *condition = kCondLT; - *opposite = kCondGE; - } - } - - return value; -} - static std::pair<Condition, Condition> GenerateLongTestConstant(HCondition* condition, bool invert, CodeGeneratorARM* codegen) { @@ -1693,7 +1665,7 @@ static std::pair<Condition, Condition> GenerateLongTestConstant(HCondition* cond std::swap(cond, opposite); } - std::pair<Condition, Condition> ret(EQ, NE); + std::pair<Condition, Condition> ret; const Location left = locations->InAt(0); const Location right = locations->InAt(1); @@ -1701,38 +1673,7 @@ static std::pair<Condition, Condition> GenerateLongTestConstant(HCondition* cond const Register left_high = left.AsRegisterPairHigh<Register>(); const Register left_low = left.AsRegisterPairLow<Register>(); - int64_t value = AdjustConstantForCondition(right.GetConstant()->AsLongConstant()->GetValue(), - &cond, - &opposite); - - // Comparisons against 0 are common enough to deserve special attention. - if (value == 0) { - switch (cond) { - case kCondNE: - // x > 0 iff x != 0 when the comparison is unsigned. - case kCondA: - ret = std::make_pair(NE, EQ); - FALLTHROUGH_INTENDED; - case kCondEQ: - // x <= 0 iff x == 0 when the comparison is unsigned. - case kCondBE: - __ orrs(IP, left_low, ShifterOperand(left_high)); - return ret; - case kCondLT: - case kCondGE: - __ cmp(left_high, ShifterOperand(0)); - return std::make_pair(ARMCondition(cond), ARMCondition(opposite)); - // Trivially true or false. - case kCondB: - ret = std::make_pair(NE, EQ); - FALLTHROUGH_INTENDED; - case kCondAE: - __ cmp(left_low, ShifterOperand(left_low)); - return ret; - default: - break; - } - } + int64_t value = right.GetConstant()->AsLongConstant()->GetValue(); switch (cond) { case kCondEQ: @@ -1892,14 +1833,10 @@ static std::pair<Condition, Condition> GenerateTest(HCondition* condition, static bool CanGenerateTest(HCondition* condition, ArmAssembler* assembler) { if (condition->GetLeft()->GetType() == Primitive::kPrimLong) { const LocationSummary* const locations = condition->GetLocations(); + const IfCondition c = condition->GetCondition(); if (locations->InAt(1).IsConstant()) { - IfCondition c = condition->GetCondition(); - IfCondition opposite = condition->GetOppositeCondition(); - const int64_t value = AdjustConstantForCondition( - Int64FromConstant(locations->InAt(1).GetConstant()), - &c, - &opposite); + const int64_t value = locations->InAt(1).GetConstant()->AsLongConstant()->GetValue(); ShifterOperand so; if (c < kCondLT || c > kCondGE) { @@ -1907,11 +1844,9 @@ static bool CanGenerateTest(HCondition* condition, ArmAssembler* assembler) { // we check that the least significant half of the first input to be compared // is in a low register (the other half is read outside an IT block), and // the constant fits in an 8-bit unsigned integer, so that a 16-bit CMP - // encoding can be used; 0 is always handled, no matter what registers are - // used by the first input. - if (value != 0 && - (!ArmAssembler::IsLowRegister(locations->InAt(0).AsRegisterPairLow<Register>()) || - !IsUint<8>(Low32Bits(value)))) { + // encoding can be used. + if (!ArmAssembler::IsLowRegister(locations->InAt(0).AsRegisterPairLow<Register>()) || + !IsUint<8>(Low32Bits(value))) { return false; } } else if (c == kCondLE || c == kCondGT) { @@ -1938,329 +1873,6 @@ static bool CanGenerateTest(HCondition* condition, ArmAssembler* assembler) { return true; } -static void GenerateConditionGeneric(HCondition* cond, CodeGeneratorARM* codegen) { - DCHECK(CanGenerateTest(cond, codegen->GetAssembler())); - - const Register out = cond->GetLocations()->Out().AsRegister<Register>(); - const auto condition = GenerateTest(cond, false, codegen); - - __ mov(out, ShifterOperand(0), AL, kCcKeep); - - if (ArmAssembler::IsLowRegister(out)) { - __ it(condition.first); - __ mov(out, ShifterOperand(1), condition.first); - } else { - Label done_label; - Label* const final_label = codegen->GetFinalLabel(cond, &done_label); - - __ b(final_label, condition.second); - __ LoadImmediate(out, 1); - - if (done_label.IsLinked()) { - __ Bind(&done_label); - } - } -} - -static void GenerateEqualLong(HCondition* cond, CodeGeneratorARM* codegen) { - DCHECK_EQ(cond->GetLeft()->GetType(), Primitive::kPrimLong); - - const LocationSummary* const locations = cond->GetLocations(); - IfCondition condition = cond->GetCondition(); - const Register out = locations->Out().AsRegister<Register>(); - const Location left = locations->InAt(0); - const Location right = locations->InAt(1); - Register left_high = left.AsRegisterPairHigh<Register>(); - Register left_low = left.AsRegisterPairLow<Register>(); - - if (right.IsConstant()) { - IfCondition opposite = cond->GetOppositeCondition(); - const int64_t value = AdjustConstantForCondition(Int64FromConstant(right.GetConstant()), - &condition, - &opposite); - int32_t value_high = -High32Bits(value); - int32_t value_low = -Low32Bits(value); - - // The output uses Location::kNoOutputOverlap. - if (out == left_high) { - std::swap(left_low, left_high); - std::swap(value_low, value_high); - } - - __ AddConstant(out, left_low, value_low); - __ AddConstant(IP, left_high, value_high); - } else { - DCHECK(right.IsRegisterPair()); - __ sub(IP, left_high, ShifterOperand(right.AsRegisterPairHigh<Register>())); - __ sub(out, left_low, ShifterOperand(right.AsRegisterPairLow<Register>())); - } - - // Need to check after calling AdjustConstantForCondition(). - DCHECK(condition == kCondEQ || condition == kCondNE) << condition; - - if (condition == kCondNE && ArmAssembler::IsLowRegister(out)) { - __ orrs(out, out, ShifterOperand(IP)); - __ it(NE); - __ mov(out, ShifterOperand(1), NE); - } else { - __ orr(out, out, ShifterOperand(IP)); - codegen->GenerateConditionWithZero(condition, out, out, IP); - } -} - -static void GenerateLongComparesAndJumps(HCondition* cond, - Label* true_label, - Label* false_label, - CodeGeneratorARM* codegen) { - LocationSummary* locations = cond->GetLocations(); - Location left = locations->InAt(0); - Location right = locations->InAt(1); - IfCondition if_cond = cond->GetCondition(); - - Register left_high = left.AsRegisterPairHigh<Register>(); - Register left_low = left.AsRegisterPairLow<Register>(); - IfCondition true_high_cond = if_cond; - IfCondition false_high_cond = cond->GetOppositeCondition(); - Condition final_condition = ARMUnsignedCondition(if_cond); // unsigned on lower part - - // Set the conditions for the test, remembering that == needs to be - // decided using the low words. - switch (if_cond) { - case kCondEQ: - case kCondNE: - // Nothing to do. - break; - case kCondLT: - false_high_cond = kCondGT; - break; - case kCondLE: - true_high_cond = kCondLT; - break; - case kCondGT: - false_high_cond = kCondLT; - break; - case kCondGE: - true_high_cond = kCondGT; - break; - case kCondB: - false_high_cond = kCondA; - break; - case kCondBE: - true_high_cond = kCondB; - break; - case kCondA: - false_high_cond = kCondB; - break; - case kCondAE: - true_high_cond = kCondA; - break; - } - if (right.IsConstant()) { - int64_t value = right.GetConstant()->AsLongConstant()->GetValue(); - int32_t val_low = Low32Bits(value); - int32_t val_high = High32Bits(value); - - __ CmpConstant(left_high, val_high); - if (if_cond == kCondNE) { - __ b(true_label, ARMCondition(true_high_cond)); - } else if (if_cond == kCondEQ) { - __ b(false_label, ARMCondition(false_high_cond)); - } else { - __ b(true_label, ARMCondition(true_high_cond)); - __ b(false_label, ARMCondition(false_high_cond)); - } - // Must be equal high, so compare the lows. - __ CmpConstant(left_low, val_low); - } else { - Register right_high = right.AsRegisterPairHigh<Register>(); - Register right_low = right.AsRegisterPairLow<Register>(); - - __ cmp(left_high, ShifterOperand(right_high)); - if (if_cond == kCondNE) { - __ b(true_label, ARMCondition(true_high_cond)); - } else if (if_cond == kCondEQ) { - __ b(false_label, ARMCondition(false_high_cond)); - } else { - __ b(true_label, ARMCondition(true_high_cond)); - __ b(false_label, ARMCondition(false_high_cond)); - } - // Must be equal high, so compare the lows. - __ cmp(left_low, ShifterOperand(right_low)); - } - // The last comparison might be unsigned. - // TODO: optimize cases where this is always true/false - __ b(true_label, final_condition); -} - -static void GenerateConditionLong(HCondition* cond, CodeGeneratorARM* codegen) { - DCHECK_EQ(cond->GetLeft()->GetType(), Primitive::kPrimLong); - - const LocationSummary* const locations = cond->GetLocations(); - IfCondition condition = cond->GetCondition(); - const Register out = locations->Out().AsRegister<Register>(); - const Location left = locations->InAt(0); - const Location right = locations->InAt(1); - - if (right.IsConstant()) { - IfCondition opposite = cond->GetOppositeCondition(); - - // Comparisons against 0 are common enough to deserve special attention. - if (AdjustConstantForCondition(Int64FromConstant(right.GetConstant()), - &condition, - &opposite) == 0) { - switch (condition) { - case kCondNE: - case kCondA: - if (ArmAssembler::IsLowRegister(out)) { - // We only care if both input registers are 0 or not. - __ orrs(out, - left.AsRegisterPairLow<Register>(), - ShifterOperand(left.AsRegisterPairHigh<Register>())); - __ it(NE); - __ mov(out, ShifterOperand(1), NE); - return; - } - - FALLTHROUGH_INTENDED; - case kCondEQ: - case kCondBE: - // We only care if both input registers are 0 or not. - __ orr(out, - left.AsRegisterPairLow<Register>(), - ShifterOperand(left.AsRegisterPairHigh<Register>())); - codegen->GenerateConditionWithZero(condition, out, out); - return; - case kCondLT: - case kCondGE: - // We only care about the sign bit. - FALLTHROUGH_INTENDED; - case kCondAE: - case kCondB: - codegen->GenerateConditionWithZero(condition, out, left.AsRegisterPairHigh<Register>()); - return; - case kCondLE: - case kCondGT: - default: - break; - } - } - } - - if ((condition == kCondEQ || condition == kCondNE) && - // If `out` is a low register, then the GenerateConditionGeneric() - // function generates a shorter code sequence that is still branchless. - (!ArmAssembler::IsLowRegister(out) || !CanGenerateTest(cond, codegen->GetAssembler()))) { - GenerateEqualLong(cond, codegen); - return; - } - - if (CanGenerateTest(cond, codegen->GetAssembler())) { - GenerateConditionGeneric(cond, codegen); - return; - } - - // Convert the jumps into the result. - Label done_label; - Label* const final_label = codegen->GetFinalLabel(cond, &done_label); - Label true_label, false_label; - - GenerateLongComparesAndJumps(cond, &true_label, &false_label, codegen); - - // False case: result = 0. - __ Bind(&false_label); - __ mov(out, ShifterOperand(0)); - __ b(final_label); - - // True case: result = 1. - __ Bind(&true_label); - __ mov(out, ShifterOperand(1)); - - if (done_label.IsLinked()) { - __ Bind(&done_label); - } -} - -static void GenerateConditionIntegralOrNonPrimitive(HCondition* cond, CodeGeneratorARM* codegen) { - const Primitive::Type type = cond->GetLeft()->GetType(); - - DCHECK(Primitive::IsIntegralType(type) || type == Primitive::kPrimNot) << type; - - if (type == Primitive::kPrimLong) { - GenerateConditionLong(cond, codegen); - return; - } - - const LocationSummary* const locations = cond->GetLocations(); - IfCondition condition = cond->GetCondition(); - Register in = locations->InAt(0).AsRegister<Register>(); - const Register out = locations->Out().AsRegister<Register>(); - const Location right = cond->GetLocations()->InAt(1); - int64_t value; - - if (right.IsConstant()) { - IfCondition opposite = cond->GetOppositeCondition(); - - value = AdjustConstantForCondition(Int64FromConstant(right.GetConstant()), - &condition, - &opposite); - - // Comparisons against 0 are common enough to deserve special attention. - if (value == 0) { - switch (condition) { - case kCondNE: - case kCondA: - if (ArmAssembler::IsLowRegister(out) && out == in) { - __ cmp(out, ShifterOperand(0)); - __ it(NE); - __ mov(out, ShifterOperand(1), NE); - return; - } - - FALLTHROUGH_INTENDED; - case kCondEQ: - case kCondBE: - case kCondLT: - case kCondGE: - case kCondAE: - case kCondB: - codegen->GenerateConditionWithZero(condition, out, in); - return; - case kCondLE: - case kCondGT: - default: - break; - } - } - } - - if (condition == kCondEQ || condition == kCondNE) { - ShifterOperand operand; - - if (right.IsConstant()) { - operand = ShifterOperand(value); - } else if (out == right.AsRegister<Register>()) { - // Avoid 32-bit instructions if possible. - operand = ShifterOperand(in); - in = right.AsRegister<Register>(); - } else { - operand = ShifterOperand(right.AsRegister<Register>()); - } - - if (condition == kCondNE && ArmAssembler::IsLowRegister(out)) { - __ subs(out, in, operand); - __ it(NE); - __ mov(out, ShifterOperand(1), NE); - } else { - __ sub(out, in, operand); - codegen->GenerateConditionWithZero(condition, out, out); - } - - return; - } - - GenerateConditionGeneric(cond, codegen); -} - static bool CanEncodeConstantAs8BitImmediate(HConstant* constant) { const Primitive::Type type = constant->GetType(); bool ret = false; @@ -2867,6 +2479,89 @@ void LocationsBuilderARM::VisitExit(HExit* exit) { void InstructionCodeGeneratorARM::VisitExit(HExit* exit ATTRIBUTE_UNUSED) { } +void InstructionCodeGeneratorARM::GenerateLongComparesAndJumps(HCondition* cond, + Label* true_label, + Label* false_label) { + LocationSummary* locations = cond->GetLocations(); + Location left = locations->InAt(0); + Location right = locations->InAt(1); + IfCondition if_cond = cond->GetCondition(); + + Register left_high = left.AsRegisterPairHigh<Register>(); + Register left_low = left.AsRegisterPairLow<Register>(); + IfCondition true_high_cond = if_cond; + IfCondition false_high_cond = cond->GetOppositeCondition(); + Condition final_condition = ARMUnsignedCondition(if_cond); // unsigned on lower part + + // Set the conditions for the test, remembering that == needs to be + // decided using the low words. + switch (if_cond) { + case kCondEQ: + case kCondNE: + // Nothing to do. + break; + case kCondLT: + false_high_cond = kCondGT; + break; + case kCondLE: + true_high_cond = kCondLT; + break; + case kCondGT: + false_high_cond = kCondLT; + break; + case kCondGE: + true_high_cond = kCondGT; + break; + case kCondB: + false_high_cond = kCondA; + break; + case kCondBE: + true_high_cond = kCondB; + break; + case kCondA: + false_high_cond = kCondB; + break; + case kCondAE: + true_high_cond = kCondA; + break; + } + if (right.IsConstant()) { + int64_t value = right.GetConstant()->AsLongConstant()->GetValue(); + int32_t val_low = Low32Bits(value); + int32_t val_high = High32Bits(value); + + __ CmpConstant(left_high, val_high); + if (if_cond == kCondNE) { + __ b(true_label, ARMCondition(true_high_cond)); + } else if (if_cond == kCondEQ) { + __ b(false_label, ARMCondition(false_high_cond)); + } else { + __ b(true_label, ARMCondition(true_high_cond)); + __ b(false_label, ARMCondition(false_high_cond)); + } + // Must be equal high, so compare the lows. + __ CmpConstant(left_low, val_low); + } else { + Register right_high = right.AsRegisterPairHigh<Register>(); + Register right_low = right.AsRegisterPairLow<Register>(); + + __ cmp(left_high, ShifterOperand(right_high)); + if (if_cond == kCondNE) { + __ b(true_label, ARMCondition(true_high_cond)); + } else if (if_cond == kCondEQ) { + __ b(false_label, ARMCondition(false_high_cond)); + } else { + __ b(true_label, ARMCondition(true_high_cond)); + __ b(false_label, ARMCondition(false_high_cond)); + } + // Must be equal high, so compare the lows. + __ cmp(left_low, ShifterOperand(right_low)); + } + // The last comparison might be unsigned. + // TODO: optimize cases where this is always true/false + __ b(true_label, final_condition); +} + void InstructionCodeGeneratorARM::GenerateCompareTestAndBranch(HCondition* condition, Label* true_target_in, Label* false_target_in) { @@ -2901,7 +2596,7 @@ void InstructionCodeGeneratorARM::GenerateCompareTestAndBranch(HCondition* condi Label* false_target = false_target_in == nullptr ? &fallthrough_target : false_target_in; DCHECK_EQ(condition->InputAt(0)->GetType(), Primitive::kPrimLong); - GenerateLongComparesAndJumps(condition, true_target, false_target, codegen_); + GenerateLongComparesAndJumps(condition, true_target, false_target); if (false_target != &fallthrough_target) { __ b(false_target); @@ -3216,80 +2911,6 @@ void CodeGeneratorARM::GenerateNop() { __ nop(); } -// `temp` is an extra temporary register that is used for some conditions; -// callers may not specify it, in which case the method will use a scratch -// register instead. -void CodeGeneratorARM::GenerateConditionWithZero(IfCondition condition, - Register out, - Register in, - Register temp) { - switch (condition) { - case kCondEQ: - // x <= 0 iff x == 0 when the comparison is unsigned. - case kCondBE: - if (temp == kNoRegister || (ArmAssembler::IsLowRegister(out) && out != in)) { - temp = out; - } - - // Avoid 32-bit instructions if possible; note that `in` and `temp` must be - // different as well. - if (ArmAssembler::IsLowRegister(in) && ArmAssembler::IsLowRegister(temp) && in != temp) { - // temp = - in; only 0 sets the carry flag. - __ rsbs(temp, in, ShifterOperand(0)); - - if (out == in) { - std::swap(in, temp); - } - - // out = - in + in + carry = carry - __ adc(out, temp, ShifterOperand(in)); - } else { - // If `in` is 0, then it has 32 leading zeros, and less than that otherwise. - __ clz(out, in); - // Any number less than 32 logically shifted right by 5 bits results in 0; - // the same operation on 32 yields 1. - __ Lsr(out, out, 5); - } - - break; - case kCondNE: - // x > 0 iff x != 0 when the comparison is unsigned. - case kCondA: - if (out == in) { - if (temp == kNoRegister || in == temp) { - temp = IP; - } - } else if (temp == kNoRegister || !ArmAssembler::IsLowRegister(temp)) { - temp = out; - } - - // temp = in - 1; only 0 does not set the carry flag. - __ subs(temp, in, ShifterOperand(1)); - // out = in + ~temp + carry = in + (-(in - 1) - 1) + carry = in - in + 1 - 1 + carry = carry - __ sbc(out, in, ShifterOperand(temp)); - break; - case kCondGE: - __ mvn(out, ShifterOperand(in)); - in = out; - FALLTHROUGH_INTENDED; - case kCondLT: - // We only care about the sign bit. - __ Lsr(out, in, 31); - break; - case kCondAE: - // Trivially true. - __ mov(out, ShifterOperand(1)); - break; - case kCondB: - // Trivially false. - __ mov(out, ShifterOperand(0)); - break; - default: - LOG(FATAL) << "Unexpected condition " << condition; - UNREACHABLE(); - } -} - void LocationsBuilderARM::HandleCondition(HCondition* cond) { LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(cond, LocationSummary::kNoCall); @@ -3326,42 +2947,48 @@ void InstructionCodeGeneratorARM::HandleCondition(HCondition* cond) { return; } - const Primitive::Type type = cond->GetLeft()->GetType(); + const Register out = cond->GetLocations()->Out().AsRegister<Register>(); - if (Primitive::IsFloatingPointType(type)) { - GenerateConditionGeneric(cond, codegen_); + if (ArmAssembler::IsLowRegister(out) && CanGenerateTest(cond, codegen_->GetAssembler())) { + const auto condition = GenerateTest(cond, false, codegen_); + + __ it(condition.first); + __ mov(out, ShifterOperand(1), condition.first); + __ it(condition.second); + __ mov(out, ShifterOperand(0), condition.second); return; } - DCHECK(Primitive::IsIntegralType(type) || type == Primitive::kPrimNot) << type; - - if (type == Primitive::kPrimBoolean) { - const LocationSummary* const locations = cond->GetLocations(); - const IfCondition c = cond->GetCondition(); - Register left = locations->InAt(0).AsRegister<Register>(); - const Register out = locations->Out().AsRegister<Register>(); - const Location right_loc = locations->InAt(1); + // Convert the jumps into the result. + Label done_label; + Label* const final_label = codegen_->GetFinalLabel(cond, &done_label); - // All other cases are handled by the instruction simplifier. - DCHECK((c == kCondEQ || c == kCondNE) && !right_loc.IsConstant()); + if (cond->InputAt(0)->GetType() == Primitive::kPrimLong) { + Label true_label, false_label; - Register right = right_loc.AsRegister<Register>(); + GenerateLongComparesAndJumps(cond, &true_label, &false_label); - // Avoid 32-bit instructions if possible. - if (out == right) { - std::swap(left, right); - } + // False case: result = 0. + __ Bind(&false_label); + __ LoadImmediate(out, 0); + __ b(final_label); - __ eor(out, left, ShifterOperand(right)); + // True case: result = 1. + __ Bind(&true_label); + __ LoadImmediate(out, 1); + } else { + DCHECK(CanGenerateTest(cond, codegen_->GetAssembler())); - if (c == kCondEQ) { - __ eor(out, out, ShifterOperand(1)); - } + const auto condition = GenerateTest(cond, false, codegen_); - return; + __ mov(out, ShifterOperand(0), AL, kCcKeep); + __ b(final_label, condition.second); + __ LoadImmediate(out, 1); } - GenerateConditionIntegralOrNonPrimitive(cond, codegen_); + if (done_label.IsLinked()) { + __ Bind(&done_label); + } } void LocationsBuilderARM::VisitEqual(HEqual* comp) { |