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 template <typename T> 16 static std::optional<Expr<SomeType>> ZeroExtend(const Constant<T> &c) { 17 std::vector<Scalar<LargestInt>> exts; 18 for (const auto &v : c.values()) { 19 exts.push_back(Scalar<LargestInt>::ConvertUnsigned(v).value); 20 } 21 return AsGenericExpr( 22 Constant<LargestInt>(std::move(exts), ConstantSubscripts(c.shape()))); 23 } 24 25 // for ALL, ANY & PARITY 26 template <typename T> 27 static Expr<T> FoldAllAnyParity(FoldingContext &context, FunctionRef<T> &&ref, 28 Scalar<T> (Scalar<T>::*operation)(const Scalar<T> &) const, 29 Scalar<T> identity) { 30 static_assert(T::category == TypeCategory::Logical); 31 using Element = Scalar<T>; 32 std::optional<int> dim; 33 if (std::optional<Constant<T>> array{ 34 ProcessReductionArgs<T>(context, ref.arguments(), dim, identity, 35 /*ARRAY(MASK)=*/0, /*DIM=*/1)}) { 36 auto accumulator{[&](Element &element, const ConstantSubscripts &at) { 37 element = (element.*operation)(array->At(at)); 38 }}; 39 return Expr<T>{DoReduction<T>(*array, dim, identity, accumulator)}; 40 } 41 return Expr<T>{std::move(ref)}; 42 } 43 44 template <int KIND> 45 Expr<Type<TypeCategory::Logical, KIND>> FoldIntrinsicFunction( 46 FoldingContext &context, 47 FunctionRef<Type<TypeCategory::Logical, KIND>> &&funcRef) { 48 using T = Type<TypeCategory::Logical, KIND>; 49 ActualArguments &args{funcRef.arguments()}; 50 auto *intrinsic{std::get_if<SpecificIntrinsic>(&funcRef.proc().u)}; 51 CHECK(intrinsic); 52 std::string name{intrinsic->name}; 53 using SameInt = Type<TypeCategory::Integer, KIND>; 54 if (name == "all") { 55 return FoldAllAnyParity( 56 context, std::move(funcRef), &Scalar<T>::AND, Scalar<T>{true}); 57 } else if (name == "any") { 58 return FoldAllAnyParity( 59 context, std::move(funcRef), &Scalar<T>::OR, Scalar<T>{false}); 60 } else if (name == "associated") { 61 bool gotConstant{true}; 62 const Expr<SomeType> *firstArgExpr{args[0]->UnwrapExpr()}; 63 if (!firstArgExpr || !IsNullPointer(*firstArgExpr)) { 64 gotConstant = false; 65 } else if (args[1]) { // There's a second argument 66 const Expr<SomeType> *secondArgExpr{args[1]->UnwrapExpr()}; 67 if (!secondArgExpr || !IsNullPointer(*secondArgExpr)) { 68 gotConstant = false; 69 } 70 } 71 return gotConstant ? Expr<T>{false} : Expr<T>{std::move(funcRef)}; 72 } else if (name == "bge" || name == "bgt" || name == "ble" || name == "blt") { 73 static_assert(std::is_same_v<Scalar<LargestInt>, BOZLiteralConstant>); 74 75 // The arguments to these intrinsics can be of different types. In that 76 // case, the shorter of the two would need to be zero-extended to match 77 // the size of the other. If at least one of the operands is not a constant, 78 // the zero-extending will be done during lowering. Otherwise, the folding 79 // must be done here. 80 std::optional<Expr<SomeType>> constArgs[2]; 81 for (int i{0}; i <= 1; i++) { 82 if (BOZLiteralConstant * x{UnwrapExpr<BOZLiteralConstant>(args[i])}) { 83 constArgs[i] = AsGenericExpr(Constant<LargestInt>{std::move(*x)}); 84 } else if (auto *x{UnwrapExpr<Expr<SomeInteger>>(args[i])}) { 85 common::visit( 86 [&](const auto &ix) { 87 using IntT = typename std::decay_t<decltype(ix)>::Result; 88 if (auto *c{UnwrapConstantValue<IntT>(ix)}) { 89 constArgs[i] = ZeroExtend(*c); 90 } 91 }, 92 x->u); 93 } 94 } 95 96 if (constArgs[0] && constArgs[1]) { 97 auto fptr{&Scalar<LargestInt>::BGE}; 98 if (name == "bge") { // done in fptr declaration 99 } else if (name == "bgt") { 100 fptr = &Scalar<LargestInt>::BGT; 101 } else if (name == "ble") { 102 fptr = &Scalar<LargestInt>::BLE; 103 } else if (name == "blt") { 104 fptr = &Scalar<LargestInt>::BLT; 105 } else { 106 common::die("missing case to fold intrinsic function %s", name.c_str()); 107 } 108 109 for (int i{0}; i <= 1; i++) { 110 *args[i] = std::move(constArgs[i].value()); 111 } 112 113 return FoldElementalIntrinsic<T, LargestInt, LargestInt>(context, 114 std::move(funcRef), 115 ScalarFunc<T, LargestInt, LargestInt>( 116 [&fptr]( 117 const Scalar<LargestInt> &i, const Scalar<LargestInt> &j) { 118 return Scalar<T>{std::invoke(fptr, i, j)}; 119 })); 120 } else { 121 return Expr<T>{std::move(funcRef)}; 122 } 123 } else if (name == "btest") { 124 if (const auto *ix{UnwrapExpr<Expr<SomeInteger>>(args[0])}) { 125 return common::visit( 126 [&](const auto &x) { 127 using IT = ResultType<decltype(x)>; 128 return FoldElementalIntrinsic<T, IT, SameInt>(context, 129 std::move(funcRef), 130 ScalarFunc<T, IT, SameInt>( 131 [&](const Scalar<IT> &x, const Scalar<SameInt> &pos) { 132 auto posVal{pos.ToInt64()}; 133 if (posVal < 0 || posVal >= x.bits) { 134 context.messages().Say( 135 "POS=%jd out of range for BTEST"_err_en_US, 136 static_cast<std::intmax_t>(posVal)); 137 } 138 return Scalar<T>{x.BTEST(posVal)}; 139 })); 140 }, 141 ix->u); 142 } 143 } else if (name == "dot_product") { 144 return FoldDotProduct<T>(context, std::move(funcRef)); 145 } else if (name == "extends_type_of") { 146 // Type extension testing with EXTENDS_TYPE_OF() ignores any type 147 // parameters. Returns a constant truth value when the result is known now. 148 if (args[0] && args[1]) { 149 auto t0{args[0]->GetType()}; 150 auto t1{args[1]->GetType()}; 151 if (t0 && t1) { 152 if (auto result{t0->ExtendsTypeOf(*t1)}) { 153 return Expr<T>{*result}; 154 } 155 } 156 } 157 } else if (name == "isnan" || name == "__builtin_ieee_is_nan") { 158 // A warning about an invalid argument is discarded from converting 159 // the argument of isnan() / IEEE_IS_NAN(). 160 auto restorer{context.messages().DiscardMessages()}; 161 using DefaultReal = Type<TypeCategory::Real, 4>; 162 return FoldElementalIntrinsic<T, DefaultReal>(context, std::move(funcRef), 163 ScalarFunc<T, DefaultReal>([](const Scalar<DefaultReal> &x) { 164 return Scalar<T>{x.IsNotANumber()}; 165 })); 166 } else if (name == "__builtin_ieee_is_negative") { 167 auto restorer{context.messages().DiscardMessages()}; 168 using DefaultReal = Type<TypeCategory::Real, 4>; 169 return FoldElementalIntrinsic<T, DefaultReal>(context, std::move(funcRef), 170 ScalarFunc<T, DefaultReal>([](const Scalar<DefaultReal> &x) { 171 return Scalar<T>{x.IsNegative()}; 172 })); 173 } else if (name == "__builtin_ieee_is_normal") { 174 auto restorer{context.messages().DiscardMessages()}; 175 using DefaultReal = Type<TypeCategory::Real, 4>; 176 return FoldElementalIntrinsic<T, DefaultReal>(context, std::move(funcRef), 177 ScalarFunc<T, DefaultReal>([](const Scalar<DefaultReal> &x) { 178 return Scalar<T>{x.IsNormal()}; 179 })); 180 } else if (name == "is_contiguous") { 181 if (args.at(0)) { 182 if (auto *expr{args[0]->UnwrapExpr()}) { 183 if (IsSimplyContiguous(*expr, context)) { 184 return Expr<T>{true}; 185 } 186 } 187 } 188 } else if (name == "lge" || name == "lgt" || name == "lle" || name == "llt") { 189 // Rewrite LGE/LGT/LLE/LLT into ASCII character relations 190 auto *cx0{UnwrapExpr<Expr<SomeCharacter>>(args[0])}; 191 auto *cx1{UnwrapExpr<Expr<SomeCharacter>>(args[1])}; 192 if (cx0 && cx1) { 193 return Fold(context, 194 ConvertToType<T>( 195 PackageRelation(name == "lge" ? RelationalOperator::GE 196 : name == "lgt" ? RelationalOperator::GT 197 : name == "lle" ? RelationalOperator::LE 198 : RelationalOperator::LT, 199 ConvertToType<Ascii>(std::move(*cx0)), 200 ConvertToType<Ascii>(std::move(*cx1))))); 201 } 202 } else if (name == "logical") { 203 if (auto *expr{UnwrapExpr<Expr<SomeLogical>>(args[0])}) { 204 return Fold(context, ConvertToType<T>(std::move(*expr))); 205 } 206 } else if (name == "merge") { 207 return FoldMerge<T>(context, std::move(funcRef)); 208 } else if (name == "parity") { 209 return FoldAllAnyParity( 210 context, std::move(funcRef), &Scalar<T>::NEQV, Scalar<T>{false}); 211 } else if (name == "same_type_as") { 212 // Type equality testing with SAME_TYPE_AS() ignores any type parameters. 213 // Returns a constant truth value when the result is known now. 214 if (args[0] && args[1]) { 215 auto t0{args[0]->GetType()}; 216 auto t1{args[1]->GetType()}; 217 if (t0 && t1) { 218 if (auto result{t0->SameTypeAs(*t1)}) { 219 return Expr<T>{*result}; 220 } 221 } 222 } 223 } else if (name == "__builtin_ieee_support_datatype" || 224 name == "__builtin_ieee_support_denormal" || 225 name == "__builtin_ieee_support_divide" || 226 name == "__builtin_ieee_support_divide" || 227 name == "__builtin_ieee_support_inf" || 228 name == "__builtin_ieee_support_io" || 229 name == "__builtin_ieee_support_nan" || 230 name == "__builtin_ieee_support_sqrt" || 231 name == "__builtin_ieee_support_standard" || 232 name == "__builtin_ieee_support_subnormal" || 233 name == "__builtin_ieee_support_underflow_control") { 234 return Expr<T>{true}; 235 } 236 // TODO: is_iostat_end, 237 // is_iostat_eor, logical, matmul, out_of_range, 238 // parity 239 return Expr<T>{std::move(funcRef)}; 240 } 241 242 template <typename T> 243 Expr<LogicalResult> FoldOperation( 244 FoldingContext &context, Relational<T> &&relation) { 245 if (auto array{ApplyElementwise(context, relation, 246 std::function<Expr<LogicalResult>(Expr<T> &&, Expr<T> &&)>{ 247 [=](Expr<T> &&x, Expr<T> &&y) { 248 return Expr<LogicalResult>{Relational<SomeType>{ 249 Relational<T>{relation.opr, std::move(x), std::move(y)}}}; 250 }})}) { 251 return *array; 252 } 253 if (auto folded{OperandsAreConstants(relation)}) { 254 bool result{}; 255 if constexpr (T::category == TypeCategory::Integer) { 256 result = 257 Satisfies(relation.opr, folded->first.CompareSigned(folded->second)); 258 } else if constexpr (T::category == TypeCategory::Real) { 259 result = Satisfies(relation.opr, folded->first.Compare(folded->second)); 260 } else if constexpr (T::category == TypeCategory::Complex) { 261 result = (relation.opr == RelationalOperator::EQ) == 262 folded->first.Equals(folded->second); 263 } else if constexpr (T::category == TypeCategory::Character) { 264 result = Satisfies(relation.opr, Compare(folded->first, folded->second)); 265 } else { 266 static_assert(T::category != TypeCategory::Logical); 267 } 268 return Expr<LogicalResult>{Constant<LogicalResult>{result}}; 269 } 270 return Expr<LogicalResult>{Relational<SomeType>{std::move(relation)}}; 271 } 272 273 Expr<LogicalResult> FoldOperation( 274 FoldingContext &context, Relational<SomeType> &&relation) { 275 return common::visit( 276 [&](auto &&x) { 277 return Expr<LogicalResult>{FoldOperation(context, std::move(x))}; 278 }, 279 std::move(relation.u)); 280 } 281 282 template <int KIND> 283 Expr<Type<TypeCategory::Logical, KIND>> FoldOperation( 284 FoldingContext &context, Not<KIND> &&x) { 285 if (auto array{ApplyElementwise(context, x)}) { 286 return *array; 287 } 288 using Ty = Type<TypeCategory::Logical, KIND>; 289 auto &operand{x.left()}; 290 if (auto value{GetScalarConstantValue<Ty>(operand)}) { 291 return Expr<Ty>{Constant<Ty>{!value->IsTrue()}}; 292 } 293 return Expr<Ty>{x}; 294 } 295 296 template <int KIND> 297 Expr<Type<TypeCategory::Logical, KIND>> FoldOperation( 298 FoldingContext &context, LogicalOperation<KIND> &&operation) { 299 using LOGICAL = Type<TypeCategory::Logical, KIND>; 300 if (auto array{ApplyElementwise(context, operation, 301 std::function<Expr<LOGICAL>(Expr<LOGICAL> &&, Expr<LOGICAL> &&)>{ 302 [=](Expr<LOGICAL> &&x, Expr<LOGICAL> &&y) { 303 return Expr<LOGICAL>{LogicalOperation<KIND>{ 304 operation.logicalOperator, std::move(x), std::move(y)}}; 305 }})}) { 306 return *array; 307 } 308 if (auto folded{OperandsAreConstants(operation)}) { 309 bool xt{folded->first.IsTrue()}, yt{folded->second.IsTrue()}, result{}; 310 switch (operation.logicalOperator) { 311 case LogicalOperator::And: 312 result = xt && yt; 313 break; 314 case LogicalOperator::Or: 315 result = xt || yt; 316 break; 317 case LogicalOperator::Eqv: 318 result = xt == yt; 319 break; 320 case LogicalOperator::Neqv: 321 result = xt != yt; 322 break; 323 case LogicalOperator::Not: 324 DIE("not a binary operator"); 325 } 326 return Expr<LOGICAL>{Constant<LOGICAL>{result}}; 327 } 328 return Expr<LOGICAL>{std::move(operation)}; 329 } 330 331 #ifdef _MSC_VER // disable bogus warning about missing definitions 332 #pragma warning(disable : 4661) 333 #endif 334 FOR_EACH_LOGICAL_KIND(template class ExpressionBase, ) 335 template class ExpressionBase<SomeLogical>; 336 } // namespace Fortran::evaluate 337