1 //===-- lib/Evaluate/fold-logical.cpp -------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "fold-implementation.h" 10 #include "fold-reduction.h" 11 #include "flang/Evaluate/check-expression.h" 12 13 namespace Fortran::evaluate { 14 15 // for ALL & ANY 16 template <typename T> 17 static Expr<T> FoldAllAny(FoldingContext &context, FunctionRef<T> &&ref, 18 Scalar<T> (Scalar<T>::*operation)(const Scalar<T> &) const, 19 Scalar<T> identity) { 20 static_assert(T::category == TypeCategory::Logical); 21 using Element = Scalar<T>; 22 std::optional<int> dim; 23 if (std::optional<Constant<T>> array{ 24 ProcessReductionArgs<T>(context, ref.arguments(), dim, identity, 25 /*ARRAY(MASK)=*/0, /*DIM=*/1)}) { 26 auto accumulator{[&](Element &element, const ConstantSubscripts &at) { 27 element = (element.*operation)(array->At(at)); 28 }}; 29 return Expr<T>{DoReduction<T>(*array, dim, identity, accumulator)}; 30 } 31 return Expr<T>{std::move(ref)}; 32 } 33 34 template <int KIND> 35 Expr<Type<TypeCategory::Logical, KIND>> FoldIntrinsicFunction( 36 FoldingContext &context, 37 FunctionRef<Type<TypeCategory::Logical, KIND>> &&funcRef) { 38 using T = Type<TypeCategory::Logical, KIND>; 39 ActualArguments &args{funcRef.arguments()}; 40 auto *intrinsic{std::get_if<SpecificIntrinsic>(&funcRef.proc().u)}; 41 CHECK(intrinsic); 42 std::string name{intrinsic->name}; 43 if (name == "all") { 44 return FoldAllAny( 45 context, std::move(funcRef), &Scalar<T>::AND, Scalar<T>{true}); 46 } else if (name == "any") { 47 return FoldAllAny( 48 context, std::move(funcRef), &Scalar<T>::OR, Scalar<T>{false}); 49 } else if (name == "associated") { 50 bool gotConstant{true}; 51 const Expr<SomeType> *firstArgExpr{args[0]->UnwrapExpr()}; 52 if (!firstArgExpr || !IsNullPointer(*firstArgExpr)) { 53 gotConstant = false; 54 } else if (args[1]) { // There's a second argument 55 const Expr<SomeType> *secondArgExpr{args[1]->UnwrapExpr()}; 56 if (!secondArgExpr || !IsNullPointer(*secondArgExpr)) { 57 gotConstant = false; 58 } 59 } 60 return gotConstant ? Expr<T>{false} : Expr<T>{std::move(funcRef)}; 61 } else if (name == "bge" || name == "bgt" || name == "ble" || name == "blt") { 62 using LargestInt = Type<TypeCategory::Integer, 16>; 63 static_assert(std::is_same_v<Scalar<LargestInt>, BOZLiteralConstant>); 64 // Arguments do not have to be of the same integer type. Convert all 65 // arguments to the biggest integer type before comparing them to 66 // simplify. 67 for (int i{0}; i <= 1; ++i) { 68 if (auto *x{UnwrapExpr<Expr<SomeInteger>>(args[i])}) { 69 *args[i] = AsGenericExpr( 70 Fold(context, ConvertToType<LargestInt>(std::move(*x)))); 71 } else if (auto *x{UnwrapExpr<BOZLiteralConstant>(args[i])}) { 72 *args[i] = AsGenericExpr(Constant<LargestInt>{std::move(*x)}); 73 } 74 } 75 auto fptr{&Scalar<LargestInt>::BGE}; 76 if (name == "bge") { // done in fptr declaration 77 } else if (name == "bgt") { 78 fptr = &Scalar<LargestInt>::BGT; 79 } else if (name == "ble") { 80 fptr = &Scalar<LargestInt>::BLE; 81 } else if (name == "blt") { 82 fptr = &Scalar<LargestInt>::BLT; 83 } else { 84 common::die("missing case to fold intrinsic function %s", name.c_str()); 85 } 86 return FoldElementalIntrinsic<T, LargestInt, LargestInt>(context, 87 std::move(funcRef), 88 ScalarFunc<T, LargestInt, LargestInt>( 89 [&fptr](const Scalar<LargestInt> &i, const Scalar<LargestInt> &j) { 90 return Scalar<T>{std::invoke(fptr, i, j)}; 91 })); 92 } else if (name == "isnan" || name == "__builtin_ieee_is_nan") { 93 // A warning about an invalid argument is discarded from converting 94 // the argument of isnan() / IEEE_IS_NAN(). 95 auto restorer{context.messages().DiscardMessages()}; 96 using DefaultReal = Type<TypeCategory::Real, 4>; 97 return FoldElementalIntrinsic<T, DefaultReal>(context, std::move(funcRef), 98 ScalarFunc<T, DefaultReal>([](const Scalar<DefaultReal> &x) { 99 return Scalar<T>{x.IsNotANumber()}; 100 })); 101 } else if (name == "is_contiguous") { 102 if (args.at(0)) { 103 if (auto *expr{args[0]->UnwrapExpr()}) { 104 if (IsSimplyContiguous(*expr, context)) { 105 return Expr<T>{true}; 106 } 107 } 108 } 109 } else if (name == "lge" || name == "lgt" || name == "lle" || name == "llt") { 110 // Rewrite LGE/LGT/LLE/LLT into ASCII character relations 111 auto *cx0{UnwrapExpr<Expr<SomeCharacter>>(args[0])}; 112 auto *cx1{UnwrapExpr<Expr<SomeCharacter>>(args[1])}; 113 if (cx0 && cx1) { 114 return Fold(context, 115 ConvertToType<T>( 116 PackageRelation(name == "lge" ? RelationalOperator::GE 117 : name == "lgt" ? RelationalOperator::GT 118 : name == "lle" ? RelationalOperator::LE 119 : RelationalOperator::LT, 120 ConvertToType<Ascii>(std::move(*cx0)), 121 ConvertToType<Ascii>(std::move(*cx1))))); 122 } 123 } else if (name == "logical") { 124 if (auto *expr{UnwrapExpr<Expr<SomeLogical>>(args[0])}) { 125 return Fold(context, ConvertToType<T>(std::move(*expr))); 126 } 127 } else if (name == "merge") { 128 return FoldMerge<T>(context, std::move(funcRef)); 129 } else if (name == "__builtin_ieee_support_datatype" || 130 name == "__builtin_ieee_support_denormal" || 131 name == "__builtin_ieee_support_divide" || 132 name == "__builtin_ieee_support_divide" || 133 name == "__builtin_ieee_support_inf" || 134 name == "__builtin_ieee_support_io" || 135 name == "__builtin_ieee_support_nan" || 136 name == "__builtin_ieee_support_sqrt" || 137 name == "__builtin_ieee_support_standard" || 138 name == "__builtin_ieee_support_subnormal" || 139 name == "__builtin_ieee_support_underflow_control") { 140 return Expr<T>{true}; 141 } 142 // TODO: btest, dot_product, is_iostat_end, 143 // is_iostat_eor, logical, matmul, out_of_range, 144 // parity, transfer 145 return Expr<T>{std::move(funcRef)}; 146 } 147 148 template <typename T> 149 Expr<LogicalResult> FoldOperation( 150 FoldingContext &context, Relational<T> &&relation) { 151 if (auto array{ApplyElementwise(context, relation, 152 std::function<Expr<LogicalResult>(Expr<T> &&, Expr<T> &&)>{ 153 [=](Expr<T> &&x, Expr<T> &&y) { 154 return Expr<LogicalResult>{Relational<SomeType>{ 155 Relational<T>{relation.opr, std::move(x), std::move(y)}}}; 156 }})}) { 157 return *array; 158 } 159 if (auto folded{OperandsAreConstants(relation)}) { 160 bool result{}; 161 if constexpr (T::category == TypeCategory::Integer) { 162 result = 163 Satisfies(relation.opr, folded->first.CompareSigned(folded->second)); 164 } else if constexpr (T::category == TypeCategory::Real) { 165 result = Satisfies(relation.opr, folded->first.Compare(folded->second)); 166 } else if constexpr (T::category == TypeCategory::Complex) { 167 result = (relation.opr == RelationalOperator::EQ) == 168 folded->first.Equals(folded->second); 169 } else if constexpr (T::category == TypeCategory::Character) { 170 result = Satisfies(relation.opr, Compare(folded->first, folded->second)); 171 } else { 172 static_assert(T::category != TypeCategory::Logical); 173 } 174 return Expr<LogicalResult>{Constant<LogicalResult>{result}}; 175 } 176 return Expr<LogicalResult>{Relational<SomeType>{std::move(relation)}}; 177 } 178 179 Expr<LogicalResult> FoldOperation( 180 FoldingContext &context, Relational<SomeType> &&relation) { 181 return std::visit( 182 [&](auto &&x) { 183 return Expr<LogicalResult>{FoldOperation(context, std::move(x))}; 184 }, 185 std::move(relation.u)); 186 } 187 188 template <int KIND> 189 Expr<Type<TypeCategory::Logical, KIND>> FoldOperation( 190 FoldingContext &context, Not<KIND> &&x) { 191 if (auto array{ApplyElementwise(context, x)}) { 192 return *array; 193 } 194 using Ty = Type<TypeCategory::Logical, KIND>; 195 auto &operand{x.left()}; 196 if (auto value{GetScalarConstantValue<Ty>(operand)}) { 197 return Expr<Ty>{Constant<Ty>{!value->IsTrue()}}; 198 } 199 return Expr<Ty>{x}; 200 } 201 202 template <int KIND> 203 Expr<Type<TypeCategory::Logical, KIND>> FoldOperation( 204 FoldingContext &context, LogicalOperation<KIND> &&operation) { 205 using LOGICAL = Type<TypeCategory::Logical, KIND>; 206 if (auto array{ApplyElementwise(context, operation, 207 std::function<Expr<LOGICAL>(Expr<LOGICAL> &&, Expr<LOGICAL> &&)>{ 208 [=](Expr<LOGICAL> &&x, Expr<LOGICAL> &&y) { 209 return Expr<LOGICAL>{LogicalOperation<KIND>{ 210 operation.logicalOperator, std::move(x), std::move(y)}}; 211 }})}) { 212 return *array; 213 } 214 if (auto folded{OperandsAreConstants(operation)}) { 215 bool xt{folded->first.IsTrue()}, yt{folded->second.IsTrue()}, result{}; 216 switch (operation.logicalOperator) { 217 case LogicalOperator::And: 218 result = xt && yt; 219 break; 220 case LogicalOperator::Or: 221 result = xt || yt; 222 break; 223 case LogicalOperator::Eqv: 224 result = xt == yt; 225 break; 226 case LogicalOperator::Neqv: 227 result = xt != yt; 228 break; 229 case LogicalOperator::Not: 230 DIE("not a binary operator"); 231 } 232 return Expr<LOGICAL>{Constant<LOGICAL>{result}}; 233 } 234 return Expr<LOGICAL>{std::move(operation)}; 235 } 236 237 FOR_EACH_LOGICAL_KIND(template class ExpressionBase, ) 238 template class ExpressionBase<SomeLogical>; 239 } // namespace Fortran::evaluate 240