[flang][OpenMP] Implement OpenMP stylized expressions #165049
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Consider OpenMP stylized expression to be a template to be instantiated with a series of types listed on the containing directive (currently DECLARE_REDUCTION). Create a series of instantiations in the parser, allowing OpenMP special variables to be declared separately for each type.
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| @llvm/pr-subscribers-flang-parser @llvm/pr-subscribers-flang-semantics Author: Krzysztof Parzyszek (kparzysz) ChangesConsider OpenMP stylized expression to be a template to be instantiated with a series of types listed on the containing directive (currently DECLARE_REDUCTION). Create a series of instantiations in the parser, allowing OpenMP special variables to be declared separately for each type. Patch is 73.19 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/165049.diff 24 Files Affected:
diff --git a/flang/include/flang/Parser/dump-parse-tree.h b/flang/include/flang/Parser/dump-parse-tree.h index af8152deb8a52..002f67cbac6ca 100644 --- a/flang/include/flang/Parser/dump-parse-tree.h +++ b/flang/include/flang/Parser/dump-parse-tree.h @@ -596,7 +596,7 @@ class ParseTreeDumper { NODE(parser, OmpInitClause) NODE(OmpInitClause, Modifier) NODE(parser, OmpInitializerClause) - NODE(parser, OmpInitializerProc) + NODE(parser, OmpInitializerExpression) NODE(parser, OmpInReductionClause) NODE(OmpInReductionClause, Modifier) NODE(parser, OmpInteropPreference) @@ -674,6 +674,10 @@ class ParseTreeDumper { NODE_ENUM(OmpSeverityClause, Severity) NODE(parser, OmpStepComplexModifier) NODE(parser, OmpStepSimpleModifier) + NODE(parser, OmpStylizedDeclaration) + NODE(parser, OmpStylizedExpression) + NODE(parser, OmpStylizedInstance) + NODE(OmpStylizedInstance, Instance) NODE(parser, OmpTaskDependenceType) NODE_ENUM(OmpTaskDependenceType, Value) NODE(parser, OmpTaskReductionClause) diff --git a/flang/include/flang/Parser/openmp-utils.h b/flang/include/flang/Parser/openmp-utils.h index f761332c9cfd7..49db091af93a7 100644 --- a/flang/include/flang/Parser/openmp-utils.h +++ b/flang/include/flang/Parser/openmp-utils.h @@ -25,6 +25,13 @@ namespace Fortran::parser::omp { +template <typename T> constexpr auto addr_if(std::optional<T> &x) { + return x ? &*x : nullptr; +} +template <typename T> constexpr auto addr_if(const std::optional<T> &x) { + return x ? &*x : nullptr; +} + namespace detail { using D = llvm::omp::Directive; @@ -133,9 +140,24 @@ template <typename T> OmpDirectiveName GetOmpDirectiveName(const T &x) { } const OmpObjectList *GetOmpObjectList(const OmpClause &clause); + +template <typename T> +const T *GetFirstArgument(const OmpDirectiveSpecification &spec) { + for (const OmpArgument &arg : spec.Arguments().v) { + if (auto *t{std::get_if<T>(&arg.u)}) { + return t; + } + } + return nullptr; +} + const BlockConstruct *GetFortranBlockConstruct( const ExecutionPartConstruct &epc); +const OmpCombinerExpression *GetCombinerExpr( + const OmpReductionSpecifier &rspec); +const OmpInitializerExpression *GetInitializerExpr(const OmpClause &init); + } // namespace Fortran::parser::omp #endif // FORTRAN_PARSER_OPENMP_UTILS_H diff --git a/flang/include/flang/Parser/parse-tree.h b/flang/include/flang/Parser/parse-tree.h index be64ef3770c60..a3388a776cd32 100644 --- a/flang/include/flang/Parser/parse-tree.h +++ b/flang/include/flang/Parser/parse-tree.h @@ -24,7 +24,9 @@ #include "provenance.h" #include "flang/Common/idioms.h" #include "flang/Common/indirection.h" +#include "flang/Common/reference.h" #include "flang/Support/Fortran.h" +#include "llvm/ADT/ArrayRef.h" #include "llvm/Frontend/OpenACC/ACC.h.inc" #include "llvm/Frontend/OpenMP/OMP.h" #include "llvm/Frontend/OpenMP/OMPConstants.h" @@ -3504,6 +3506,8 @@ struct OmpDirectiveName { // type-name list item struct OmpTypeName { + CharBlock source; + mutable const semantics::DeclTypeSpec *declTypeSpec{nullptr}; UNION_CLASS_BOILERPLATE(OmpTypeName); std::variant<TypeSpec, DeclarationTypeSpec> u; }; @@ -3532,6 +3536,33 @@ struct OmpObjectList { WRAPPER_CLASS_BOILERPLATE(OmpObjectList, std::list<OmpObject>); }; +struct OmpStylizedDeclaration { + COPY_AND_ASSIGN_BOILERPLATE(OmpStylizedDeclaration); + // Since "Reference" isn't handled by parse-tree-visitor, add EmptyTrait, + // and visit the members by hand when needed. + using EmptyTrait = std::true_type; + common::Reference<const OmpTypeName> type; + EntityDecl var; +}; + +struct OmpStylizedInstance { + struct Instance { + UNION_CLASS_BOILERPLATE(Instance); + std::variant<AssignmentStmt, CallStmt, common::Indirection<Expr>> u; + }; + TUPLE_CLASS_BOILERPLATE(OmpStylizedInstance); + std::tuple<std::list<OmpStylizedDeclaration>, Instance> t; +}; + +class ParseState; + +struct OmpStylizedExpression { + CharBlock source; + const ParseState *state{nullptr}; + WRAPPER_CLASS_BOILERPLATE( + OmpStylizedExpression, std::list<OmpStylizedInstance>); +}; + // Ref: [4.5:201-207], [5.0:293-299], [5.1:325-331], [5.2:124] // // reduction-identifier -> @@ -3549,9 +3580,22 @@ struct OmpReductionIdentifier { // combiner-expression -> // since 4.5 // assignment-statement | // function-reference -struct OmpCombinerExpression { - UNION_CLASS_BOILERPLATE(OmpCombinerExpression); - std::variant<AssignmentStmt, FunctionReference> u; +struct OmpCombinerExpression : public OmpStylizedExpression { + INHERITED_WRAPPER_CLASS_BOILERPLATE( + OmpCombinerExpression, OmpStylizedExpression); + static llvm::ArrayRef<CharBlock> Variables(); +}; + +// Ref: [4.5:222:7-8], [5.0:305:28-29], [5.1:337:20-21], [5.2:127:6-8], +// [6.0:242:3-5] +// +// initializer-expression -> // since 4.5 +// OMP_PRIV = expression | +// subroutine-name(argument-list) +struct OmpInitializerExpression : public OmpStylizedExpression { + INHERITED_WRAPPER_CLASS_BOILERPLATE( + OmpInitializerExpression, OmpStylizedExpression); + static llvm::ArrayRef<CharBlock> Variables(); }; inline namespace arguments { @@ -4552,16 +4596,9 @@ struct OmpInReductionClause { std::tuple<MODIFIERS(), OmpObjectList> t; }; -// declare-reduction -> DECLARE REDUCTION (reduction-identifier : type-list -// : combiner) [initializer-clause] -struct OmpInitializerProc { - TUPLE_CLASS_BOILERPLATE(OmpInitializerProc); - std::tuple<ProcedureDesignator, std::list<ActualArgSpec>> t; -}; // Initialization for declare reduction construct struct OmpInitializerClause { - UNION_CLASS_BOILERPLATE(OmpInitializerClause); - std::variant<OmpInitializerProc, AssignmentStmt> u; + WRAPPER_CLASS_BOILERPLATE(OmpInitializerClause, OmpInitializerExpression); }; // Ref: [4.5:199-201], [5.0:288-290], [5.1:321-322], [5.2:115-117] diff --git a/flang/include/flang/Semantics/symbol.h b/flang/include/flang/Semantics/symbol.h index 04a063957082a..cb27d544ed9f5 100644 --- a/flang/include/flang/Semantics/symbol.h +++ b/flang/include/flang/Semantics/symbol.h @@ -830,6 +830,8 @@ class Symbol { OmpUseDevicePtr, OmpUseDeviceAddr, OmpIsDevicePtr, OmpHasDeviceAddr, // OpenMP data-copying attribute OmpCopyIn, OmpCopyPrivate, + // OpenMP special variables + OmpInVar, OmpOrigVar, OmpOutVar, OmpPrivVar, // OpenMP miscellaneous flags OmpCommonBlock, OmpReduction, OmpInReduction, OmpAligned, OmpNontemporal, OmpAllocate, OmpDeclarativeAllocateDirective, diff --git a/flang/lib/Parser/openmp-parsers.cpp b/flang/lib/Parser/openmp-parsers.cpp index d1e081cfd1b41..1f473660003a9 100644 --- a/flang/lib/Parser/openmp-parsers.cpp +++ b/flang/lib/Parser/openmp-parsers.cpp @@ -275,6 +275,13 @@ struct SpecificModifierParser { // --- Iterator helpers ----------------------------------------------- +static EntityDecl MakeEntityDecl(ObjectName &&name) { + return EntityDecl( + /*ObjectName=*/std::move(name), std::optional<ArraySpec>{}, + std::optional<CoarraySpec>{}, std::optional<CharLength>{}, + std::optional<Initialization>{}); +} + // [5.0:47:17-18] In an iterator-specifier, if the iterator-type is not // specified then the type of that iterator is default integer. // [5.0:49:14] The iterator-type must be an integer type. @@ -282,11 +289,7 @@ static std::list<EntityDecl> makeEntityList(std::list<ObjectName> &&names) { std::list<EntityDecl> entities; for (auto iter = names.begin(), end = names.end(); iter != end; ++iter) { - EntityDecl entityDecl( - /*ObjectName=*/std::move(*iter), std::optional<ArraySpec>{}, - std::optional<CoarraySpec>{}, std::optional<CharLength>{}, - std::optional<Initialization>{}); - entities.push_back(std::move(entityDecl)); + entities.push_back(MakeEntityDecl(std::move(*iter))); } return entities; } @@ -306,6 +309,207 @@ static TypeDeclarationStmt makeIterSpecDecl(std::list<ObjectName> &&names) { makeEntityList(std::move(names))); } +// --- Stylized expression handling ----------------------------------- + +// OpenMP has a concept of am "OpenMP stylized expression". Syntactially +// it looks like a typical Fortran expression (or statement), except: +// - the only variables allowed in it are OpenMP special variables, the +// exact set of these variables depends on the specific case of the +// stylized expression +// - the special OpenMP variables present may assume one or more types, +// and the expression should be semantically valid for each type. +// +// The stylized expression can be thought of as a template, which will be +// instantiated for each type provided somewhere in the context in which +// the stylized expression appears. +// +// AST nodes: +// - OmpStylizedExpression: contains the source string for the expression, +// plus the list of instances (OmpStylizedInstance). +// - OmpStylizedInstance: corresponds to the instantiation of the stylized +// expression for a specific type. The way that the type is specified is +// by creating declarations (OmpStylizedDeclaration) for the special +// variables. Together with the AST tree corresponding to the stylized +// expression the instantiation has enough information for semantic +// analysis. Each instance has its own scope, and the special variables +// have their own Symbol's (local to the scope). +// - OmpStylizedDeclaration: encapsulates the information that the visitors +// in resolve-names can use to "emulate" a declaration for a special +// variable and allow name resolution in the instantiation AST to work. +// +// Implementation specifics: +// The semantic analysis stores "evaluate::Expr" in each AST node rooted +// in parser::Expr (in the typedExpr member). The evaluate::Expr is specific +// to a given type, and so to allow different types for a given expression, +// for each type a separate copy of the parsee::Expr subtree is created. +// Normally, AST nodes are non-copyable (copy-ctor is deleted), so to create +// several copies of a subtree, the same source string is parsed several +// times. The ParseState member in OmpStylizedExpression is the parser state +// immediately before the stylized expression. +// +// Initially, when OmpStylizedExpression is first created, the expression is +// parsed as if it was an actual code, but this parsing is only done to +// establish where the stylized expression ends (in the source). The source +// and the initial parser state are store in the object, and the instance +// list is empty. +// Once the parsing of the containing OmpDirectiveSpecification completes, +// a post-processing "parser" (OmpStylizedInstanceCreator) executes. This +// post-processor examines the directive specification to see if it expects +// any stylized expressions to be contained in it, and then instantiates +// them for each such directive. + +template <typename A> struct NeverParser { + using resultType = A; + std::optional<resultType> Parse(ParseState &state) const { + // Always fail, but without any messages. + return std::nullopt; + } +}; + +template <typename A> constexpr auto never() { return NeverParser<A>{}; } + +template <typename A, typename B = void> struct NullParser; +template <typename B> struct NullParser<std::optional<B>> { + using resultType = std::optional<B>; + std::optional<resultType> Parse(ParseState &) const { + return resultType{std::nullopt}; + } +}; + +template <typename A> constexpr auto null() { return NullParser<A>{}; } + +// OmpStylizedDeclaration and OmpStylizedInstance are helper classes, and +// don't correspond to anything in the source. Their parsers should still +// exist, but they should never be executed. +TYPE_PARSER(construct<OmpStylizedDeclaration>(never<OmpStylizedDeclaration>())) + +TYPE_PARSER( // + construct<OmpStylizedInstance::Instance>(Parser<AssignmentStmt>{}) || + construct<OmpStylizedInstance::Instance>( + sourced(construct<CallStmt>(Parser<ProcedureDesignator>{}, + null<std::optional<CallStmt::Chevrons>>(), + parenthesized(optionalList(actualArgSpec))))) || + construct<OmpStylizedInstance::Instance>(indirect(expr))) + +TYPE_PARSER(construct<OmpStylizedInstance>(never<OmpStylizedInstance>())) + +struct OmpStylizedExpressionParser { + using resultType = OmpStylizedExpression; + + std::optional<resultType> Parse(ParseState &state) const { + auto *saved{new ParseState(state)}; + auto getSource{verbatim(Parser<OmpStylizedInstance::Instance>{} >> ok)}; + if (auto &&ok{getSource.Parse(state)}) { + OmpStylizedExpression result{std::list<OmpStylizedInstance>{}}; + result.source = ok->source; + result.state = saved; + // result.v remains empty + return std::move(result); + } + delete saved; + return std::nullopt; + } +}; + +static void Instantiate(OmpStylizedExpression &ose, + llvm::ArrayRef<const OmpTypeName *> types, llvm::ArrayRef<CharBlock> vars) { + // 1. For each var in the vars list, declare it with the corresponding + // type from types. + // 2. Run the parser to get the AST for the stylized expression. + // 3. Create OmpStylizedInstance and append it to the list in ose. + assert(types.size() == vars.size() && "List size mismatch"); + ParseState state{DEREF(ose.state)}; + + std::list<OmpStylizedDeclaration> decls; + for (auto [type, var] : llvm::zip_equal(types, vars)) { + decls.emplace_back(OmpStylizedDeclaration{ + common::Reference(*type), MakeEntityDecl(Name{var})}); + } + + if (auto &&instance{Parser<OmpStylizedInstance::Instance>{}.Parse(state)}) { + ose.v.emplace_back( + OmpStylizedInstance{std::move(decls), std::move(*instance)}); + } +} + +static void InstantiateForTypes(OmpStylizedExpression &ose, + const OmpTypeNameList &typeNames, llvm::ArrayRef<CharBlock> vars) { + // For each type in the type list, declare all variables in vars with + // that type, and complete the instantiation. + for (const OmpTypeName &t : typeNames.v) { + std::vector<const OmpTypeName *> types(vars.size(), &t); + Instantiate(ose, types, vars); + } +} + +static void InstantiateDeclareReduction(OmpDirectiveSpecification &spec) { + // There can be arguments/clauses that don't make sense, that analysis + // is left until semantic checks. Tolerate any unexpected stuff. + auto *rspec{GetFirstArgument<OmpReductionSpecifier>(spec)}; + if (!rspec) { + return; + } + + const OmpTypeNameList *typeNames{nullptr}; + + if (auto *cexpr{GetCombinerExpr(*rspec)}) { + typeNames = &std::get<OmpTypeNameList>(rspec->t); + + InstantiateForTypes(const_cast<OmpCombinerExpression &>(*cexpr), *typeNames, + OmpCombinerExpression::Variables()); + delete cexpr->state; + } else { + // If there are no types, there is nothing else to do. + return; + } + + for (const OmpClause &clause : spec.Clauses().v) { + llvm::omp::Clause id{clause.Id()}; + if (id == llvm::omp::Clause::OMPC_initializer) { + if (auto *iexpr{GetInitializerExpr(clause)}) { + InstantiateForTypes(const_cast<OmpInitializerExpression &>(*iexpr), + *typeNames, OmpInitializerExpression::Variables()); + delete iexpr->state; + } + } + } +} + +static void InstantiateStylizedDirective(OmpDirectiveSpecification &spec) { + const OmpDirectiveName &dirName{spec.DirName()}; + if (dirName.v == llvm::omp::Directive::OMPD_declare_reduction) { + InstantiateDeclareReduction(spec); + } +} + +template <typename P, + typename = std::enable_if_t< + std::is_same_v<typename P::resultType, OmpDirectiveSpecification>>> +struct OmpStylizedInstanceCreator { + using resultType = OmpDirectiveSpecification; + constexpr OmpStylizedInstanceCreator(P p) : parser_(p) {} + + std::optional<resultType> Parse(ParseState &state) const { + if (auto &&spec{parser_.Parse(state)}) { + InstantiateStylizedDirective(*spec); + return std::move(spec); + } + return std::nullopt; + } + +private: + const P parser_; +}; + +template <typename P> +OmpStylizedInstanceCreator(P) -> OmpStylizedInstanceCreator<P>; + +// --- Parsers for types ---------------------------------------------- + +TYPE_PARSER( // + sourced(construct<OmpTypeName>(Parser<DeclarationTypeSpec>{})) || + sourced(construct<OmpTypeName>(Parser<TypeSpec>{}))) + // --- Parsers for arguments ------------------------------------------ // At the moment these are only directive arguments. This is needed for @@ -366,10 +570,6 @@ struct OmpArgumentListParser { } }; -TYPE_PARSER( // - construct<OmpTypeName>(Parser<DeclarationTypeSpec>{}) || - construct<OmpTypeName>(Parser<TypeSpec>{})) - // 2.15.3.6 REDUCTION (reduction-identifier: variable-name-list) TYPE_PARSER(construct<OmpReductionIdentifier>(Parser<DefinedOperator>{}) || construct<OmpReductionIdentifier>(Parser<ProcedureDesignator>{})) @@ -1065,7 +1265,8 @@ TYPE_PARSER(construct<OmpOtherwiseClause>( TYPE_PARSER(construct<OmpWhenClause>( maybe(nonemptyList(Parser<OmpWhenClause::Modifier>{}) / ":"), - maybe(indirect(Parser<OmpDirectiveSpecification>{})))) + maybe(indirect( + OmpStylizedInstanceCreator(Parser<OmpDirectiveSpecification>{}))))) // OMP 5.2 12.6.1 grainsize([ prescriptiveness :] scalar-integer-expression) TYPE_PARSER(construct<OmpGrainsizeClause>( @@ -1777,12 +1978,7 @@ TYPE_PARSER( Parser<OpenMPInteropConstruct>{})) / endOfLine) -TYPE_PARSER(construct<OmpInitializerProc>(Parser<ProcedureDesignator>{}, - parenthesized(many(maybe(","_tok) >> Parser<ActualArgSpec>{})))) - -TYPE_PARSER(construct<OmpInitializerClause>( - construct<OmpInitializerClause>(assignmentStmt) || - construct<OmpInitializerClause>(Parser<OmpInitializerProc>{}))) +TYPE_PARSER(construct<OmpInitializerClause>(Parser<OmpInitializerExpression>{})) // OpenMP 5.2: 7.5.4 Declare Variant directive TYPE_PARSER(sourced(construct<OmpDeclareVariantDirective>( @@ -1794,7 +1990,7 @@ TYPE_PARSER(sourced(construct<OmpDeclareVariantDirective>( TYPE_PARSER(sourced(construct<OpenMPDeclareReductionConstruct>( predicated(Parser<OmpDirectiveName>{}, IsDirective(llvm::omp::Directive::OMPD_declare_reduction)) >= - Parser<OmpDirectiveSpecification>{}))) + OmpStylizedInstanceCreator(Parser<OmpDirectiveSpecification>{})))) // 2.10.6 Declare Target Construct TYPE_PARSER(sourced(construct<OpenMPDeclareTargetConstruct>( @@ -1832,8 +2028,8 @@ TYPE_PARSER(sourced(construct<OpenMPDeclareMapperConstruct>( IsDirective(llvm::omp::Directive::OMPD_declare_mapper)) >= Parser<OmpDirectiveSpecification>{}))) -TYPE_PARSER(construct<OmpCombinerExpression>(Parser<AssignmentStmt>{}) || - construct<OmpCombinerExpression>(Parser<FunctionReference>{})) +TYPE_PARSER(construct<OmpCombinerExpression>(OmpStylizedExpressionParser{})) +TYPE_PARSER(construct<OmpInitializerExpression>(OmpStylizedExpressionParser{})) TYPE_PARSER(sourced(construct<OpenMPCriticalConstruct>( OmpBlockConstructParser{llvm::omp::Directive::OMPD_critical}))) diff --git a/flang/lib/Parser/openmp-utils.cpp b/flang/lib/Parser/openmp-utils.cpp index 937a17f29f221..95ad3f60770f5 100644 --- a/flang/lib/Parser/openmp-utils.cpp +++ b/flang/lib/Parser/openmp-utils.cpp @@ -74,4 +74,16 @@ const BlockConstruct *GetFortranBlockConstruct( return nullptr; } +const OmpCombinerExpression *GetCombinerExpr( + const OmpReductionSpecifier &rspec) { + return addr_if(std::get<std::optional<OmpCombinerExpression>>(rspec.t)); +} + +const OmpInitializerExpression *GetInitializerExpr(const OmpClause &init) { + if (auto *wrapped{std::get_if<OmpClause::Initializer>(&init.u)}) { + return &wrapped->v.v; + } + return nullptr; +} + } // namespace Fortran::parser::omp diff --git a/flang/lib/Parser/parse-tree.cpp b/flang/lib/Parser/parse-tree.cpp index 8cbaa399c4763..ad0016e1404f9 100644 --- a/flang/lib/Parser/parse-tree.cpp +++ b/flang/lib/Parser/parse-tree.cpp @@ -11,6 +11,7 @@ #include "flang/Common/indirection.h" #include "flang/Parser/tools.h" #include "flang/Parser/user-state.h" +#include "llvm/ADT/ArrayRef.h" #include "llvm/Frontend/OpenMP/OMP.h" #include "llvm/Support/raw_ostream.h" #include <algorithm> @@ -430,4 +431,30 @@ const OmpClauseList &OmpDirectiveSpecification::Clauses() const { ... [truncated] |
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| @llvm/pr-subscribers-flang-openmp Author: Krzysztof Parzyszek (kparzysz) ChangesConsider OpenMP stylized expression to be a template to be instantiated with a series of types listed on the containing directive (currently DECLARE_REDUCTION). Create a series of instantiations in the parser, allowing OpenMP special variables to be declared separately for each type. Patch is 73.19 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/165049.diff 24 Files Affected:
diff --git a/flang/include/flang/Parser/dump-parse-tree.h b/flang/include/flang/Parser/dump-parse-tree.h index af8152deb8a52..002f67cbac6ca 100644 --- a/flang/include/flang/Parser/dump-parse-tree.h +++ b/flang/include/flang/Parser/dump-parse-tree.h @@ -596,7 +596,7 @@ class ParseTreeDumper { NODE(parser, OmpInitClause) NODE(OmpInitClause, Modifier) NODE(parser, OmpInitializerClause) - NODE(parser, OmpInitializerProc) + NODE(parser, OmpInitializerExpression) NODE(parser, OmpInReductionClause) NODE(OmpInReductionClause, Modifier) NODE(parser, OmpInteropPreference) @@ -674,6 +674,10 @@ class ParseTreeDumper { NODE_ENUM(OmpSeverityClause, Severity) NODE(parser, OmpStepComplexModifier) NODE(parser, OmpStepSimpleModifier) + NODE(parser, OmpStylizedDeclaration) + NODE(parser, OmpStylizedExpression) + NODE(parser, OmpStylizedInstance) + NODE(OmpStylizedInstance, Instance) NODE(parser, OmpTaskDependenceType) NODE_ENUM(OmpTaskDependenceType, Value) NODE(parser, OmpTaskReductionClause) diff --git a/flang/include/flang/Parser/openmp-utils.h b/flang/include/flang/Parser/openmp-utils.h index f761332c9cfd7..49db091af93a7 100644 --- a/flang/include/flang/Parser/openmp-utils.h +++ b/flang/include/flang/Parser/openmp-utils.h @@ -25,6 +25,13 @@ namespace Fortran::parser::omp { +template <typename T> constexpr auto addr_if(std::optional<T> &x) { + return x ? &*x : nullptr; +} +template <typename T> constexpr auto addr_if(const std::optional<T> &x) { + return x ? &*x : nullptr; +} + namespace detail { using D = llvm::omp::Directive; @@ -133,9 +140,24 @@ template <typename T> OmpDirectiveName GetOmpDirectiveName(const T &x) { } const OmpObjectList *GetOmpObjectList(const OmpClause &clause); + +template <typename T> +const T *GetFirstArgument(const OmpDirectiveSpecification &spec) { + for (const OmpArgument &arg : spec.Arguments().v) { + if (auto *t{std::get_if<T>(&arg.u)}) { + return t; + } + } + return nullptr; +} + const BlockConstruct *GetFortranBlockConstruct( const ExecutionPartConstruct &epc); +const OmpCombinerExpression *GetCombinerExpr( + const OmpReductionSpecifier &rspec); +const OmpInitializerExpression *GetInitializerExpr(const OmpClause &init); + } // namespace Fortran::parser::omp #endif // FORTRAN_PARSER_OPENMP_UTILS_H diff --git a/flang/include/flang/Parser/parse-tree.h b/flang/include/flang/Parser/parse-tree.h index be64ef3770c60..a3388a776cd32 100644 --- a/flang/include/flang/Parser/parse-tree.h +++ b/flang/include/flang/Parser/parse-tree.h @@ -24,7 +24,9 @@ #include "provenance.h" #include "flang/Common/idioms.h" #include "flang/Common/indirection.h" +#include "flang/Common/reference.h" #include "flang/Support/Fortran.h" +#include "llvm/ADT/ArrayRef.h" #include "llvm/Frontend/OpenACC/ACC.h.inc" #include "llvm/Frontend/OpenMP/OMP.h" #include "llvm/Frontend/OpenMP/OMPConstants.h" @@ -3504,6 +3506,8 @@ struct OmpDirectiveName { // type-name list item struct OmpTypeName { + CharBlock source; + mutable const semantics::DeclTypeSpec *declTypeSpec{nullptr}; UNION_CLASS_BOILERPLATE(OmpTypeName); std::variant<TypeSpec, DeclarationTypeSpec> u; }; @@ -3532,6 +3536,33 @@ struct OmpObjectList { WRAPPER_CLASS_BOILERPLATE(OmpObjectList, std::list<OmpObject>); }; +struct OmpStylizedDeclaration { + COPY_AND_ASSIGN_BOILERPLATE(OmpStylizedDeclaration); + // Since "Reference" isn't handled by parse-tree-visitor, add EmptyTrait, + // and visit the members by hand when needed. + using EmptyTrait = std::true_type; + common::Reference<const OmpTypeName> type; + EntityDecl var; +}; + +struct OmpStylizedInstance { + struct Instance { + UNION_CLASS_BOILERPLATE(Instance); + std::variant<AssignmentStmt, CallStmt, common::Indirection<Expr>> u; + }; + TUPLE_CLASS_BOILERPLATE(OmpStylizedInstance); + std::tuple<std::list<OmpStylizedDeclaration>, Instance> t; +}; + +class ParseState; + +struct OmpStylizedExpression { + CharBlock source; + const ParseState *state{nullptr}; + WRAPPER_CLASS_BOILERPLATE( + OmpStylizedExpression, std::list<OmpStylizedInstance>); +}; + // Ref: [4.5:201-207], [5.0:293-299], [5.1:325-331], [5.2:124] // // reduction-identifier -> @@ -3549,9 +3580,22 @@ struct OmpReductionIdentifier { // combiner-expression -> // since 4.5 // assignment-statement | // function-reference -struct OmpCombinerExpression { - UNION_CLASS_BOILERPLATE(OmpCombinerExpression); - std::variant<AssignmentStmt, FunctionReference> u; +struct OmpCombinerExpression : public OmpStylizedExpression { + INHERITED_WRAPPER_CLASS_BOILERPLATE( + OmpCombinerExpression, OmpStylizedExpression); + static llvm::ArrayRef<CharBlock> Variables(); +}; + +// Ref: [4.5:222:7-8], [5.0:305:28-29], [5.1:337:20-21], [5.2:127:6-8], +// [6.0:242:3-5] +// +// initializer-expression -> // since 4.5 +// OMP_PRIV = expression | +// subroutine-name(argument-list) +struct OmpInitializerExpression : public OmpStylizedExpression { + INHERITED_WRAPPER_CLASS_BOILERPLATE( + OmpInitializerExpression, OmpStylizedExpression); + static llvm::ArrayRef<CharBlock> Variables(); }; inline namespace arguments { @@ -4552,16 +4596,9 @@ struct OmpInReductionClause { std::tuple<MODIFIERS(), OmpObjectList> t; }; -// declare-reduction -> DECLARE REDUCTION (reduction-identifier : type-list -// : combiner) [initializer-clause] -struct OmpInitializerProc { - TUPLE_CLASS_BOILERPLATE(OmpInitializerProc); - std::tuple<ProcedureDesignator, std::list<ActualArgSpec>> t; -}; // Initialization for declare reduction construct struct OmpInitializerClause { - UNION_CLASS_BOILERPLATE(OmpInitializerClause); - std::variant<OmpInitializerProc, AssignmentStmt> u; + WRAPPER_CLASS_BOILERPLATE(OmpInitializerClause, OmpInitializerExpression); }; // Ref: [4.5:199-201], [5.0:288-290], [5.1:321-322], [5.2:115-117] diff --git a/flang/include/flang/Semantics/symbol.h b/flang/include/flang/Semantics/symbol.h index 04a063957082a..cb27d544ed9f5 100644 --- a/flang/include/flang/Semantics/symbol.h +++ b/flang/include/flang/Semantics/symbol.h @@ -830,6 +830,8 @@ class Symbol { OmpUseDevicePtr, OmpUseDeviceAddr, OmpIsDevicePtr, OmpHasDeviceAddr, // OpenMP data-copying attribute OmpCopyIn, OmpCopyPrivate, + // OpenMP special variables + OmpInVar, OmpOrigVar, OmpOutVar, OmpPrivVar, // OpenMP miscellaneous flags OmpCommonBlock, OmpReduction, OmpInReduction, OmpAligned, OmpNontemporal, OmpAllocate, OmpDeclarativeAllocateDirective, diff --git a/flang/lib/Parser/openmp-parsers.cpp b/flang/lib/Parser/openmp-parsers.cpp index d1e081cfd1b41..1f473660003a9 100644 --- a/flang/lib/Parser/openmp-parsers.cpp +++ b/flang/lib/Parser/openmp-parsers.cpp @@ -275,6 +275,13 @@ struct SpecificModifierParser { // --- Iterator helpers ----------------------------------------------- +static EntityDecl MakeEntityDecl(ObjectName &&name) { + return EntityDecl( + /*ObjectName=*/std::move(name), std::optional<ArraySpec>{}, + std::optional<CoarraySpec>{}, std::optional<CharLength>{}, + std::optional<Initialization>{}); +} + // [5.0:47:17-18] In an iterator-specifier, if the iterator-type is not // specified then the type of that iterator is default integer. // [5.0:49:14] The iterator-type must be an integer type. @@ -282,11 +289,7 @@ static std::list<EntityDecl> makeEntityList(std::list<ObjectName> &&names) { std::list<EntityDecl> entities; for (auto iter = names.begin(), end = names.end(); iter != end; ++iter) { - EntityDecl entityDecl( - /*ObjectName=*/std::move(*iter), std::optional<ArraySpec>{}, - std::optional<CoarraySpec>{}, std::optional<CharLength>{}, - std::optional<Initialization>{}); - entities.push_back(std::move(entityDecl)); + entities.push_back(MakeEntityDecl(std::move(*iter))); } return entities; } @@ -306,6 +309,207 @@ static TypeDeclarationStmt makeIterSpecDecl(std::list<ObjectName> &&names) { makeEntityList(std::move(names))); } +// --- Stylized expression handling ----------------------------------- + +// OpenMP has a concept of am "OpenMP stylized expression". Syntactially +// it looks like a typical Fortran expression (or statement), except: +// - the only variables allowed in it are OpenMP special variables, the +// exact set of these variables depends on the specific case of the +// stylized expression +// - the special OpenMP variables present may assume one or more types, +// and the expression should be semantically valid for each type. +// +// The stylized expression can be thought of as a template, which will be +// instantiated for each type provided somewhere in the context in which +// the stylized expression appears. +// +// AST nodes: +// - OmpStylizedExpression: contains the source string for the expression, +// plus the list of instances (OmpStylizedInstance). +// - OmpStylizedInstance: corresponds to the instantiation of the stylized +// expression for a specific type. The way that the type is specified is +// by creating declarations (OmpStylizedDeclaration) for the special +// variables. Together with the AST tree corresponding to the stylized +// expression the instantiation has enough information for semantic +// analysis. Each instance has its own scope, and the special variables +// have their own Symbol's (local to the scope). +// - OmpStylizedDeclaration: encapsulates the information that the visitors +// in resolve-names can use to "emulate" a declaration for a special +// variable and allow name resolution in the instantiation AST to work. +// +// Implementation specifics: +// The semantic analysis stores "evaluate::Expr" in each AST node rooted +// in parser::Expr (in the typedExpr member). The evaluate::Expr is specific +// to a given type, and so to allow different types for a given expression, +// for each type a separate copy of the parsee::Expr subtree is created. +// Normally, AST nodes are non-copyable (copy-ctor is deleted), so to create +// several copies of a subtree, the same source string is parsed several +// times. The ParseState member in OmpStylizedExpression is the parser state +// immediately before the stylized expression. +// +// Initially, when OmpStylizedExpression is first created, the expression is +// parsed as if it was an actual code, but this parsing is only done to +// establish where the stylized expression ends (in the source). The source +// and the initial parser state are store in the object, and the instance +// list is empty. +// Once the parsing of the containing OmpDirectiveSpecification completes, +// a post-processing "parser" (OmpStylizedInstanceCreator) executes. This +// post-processor examines the directive specification to see if it expects +// any stylized expressions to be contained in it, and then instantiates +// them for each such directive. + +template <typename A> struct NeverParser { + using resultType = A; + std::optional<resultType> Parse(ParseState &state) const { + // Always fail, but without any messages. + return std::nullopt; + } +}; + +template <typename A> constexpr auto never() { return NeverParser<A>{}; } + +template <typename A, typename B = void> struct NullParser; +template <typename B> struct NullParser<std::optional<B>> { + using resultType = std::optional<B>; + std::optional<resultType> Parse(ParseState &) const { + return resultType{std::nullopt}; + } +}; + +template <typename A> constexpr auto null() { return NullParser<A>{}; } + +// OmpStylizedDeclaration and OmpStylizedInstance are helper classes, and +// don't correspond to anything in the source. Their parsers should still +// exist, but they should never be executed. +TYPE_PARSER(construct<OmpStylizedDeclaration>(never<OmpStylizedDeclaration>())) + +TYPE_PARSER( // + construct<OmpStylizedInstance::Instance>(Parser<AssignmentStmt>{}) || + construct<OmpStylizedInstance::Instance>( + sourced(construct<CallStmt>(Parser<ProcedureDesignator>{}, + null<std::optional<CallStmt::Chevrons>>(), + parenthesized(optionalList(actualArgSpec))))) || + construct<OmpStylizedInstance::Instance>(indirect(expr))) + +TYPE_PARSER(construct<OmpStylizedInstance>(never<OmpStylizedInstance>())) + +struct OmpStylizedExpressionParser { + using resultType = OmpStylizedExpression; + + std::optional<resultType> Parse(ParseState &state) const { + auto *saved{new ParseState(state)}; + auto getSource{verbatim(Parser<OmpStylizedInstance::Instance>{} >> ok)}; + if (auto &&ok{getSource.Parse(state)}) { + OmpStylizedExpression result{std::list<OmpStylizedInstance>{}}; + result.source = ok->source; + result.state = saved; + // result.v remains empty + return std::move(result); + } + delete saved; + return std::nullopt; + } +}; + +static void Instantiate(OmpStylizedExpression &ose, + llvm::ArrayRef<const OmpTypeName *> types, llvm::ArrayRef<CharBlock> vars) { + // 1. For each var in the vars list, declare it with the corresponding + // type from types. + // 2. Run the parser to get the AST for the stylized expression. + // 3. Create OmpStylizedInstance and append it to the list in ose. + assert(types.size() == vars.size() && "List size mismatch"); + ParseState state{DEREF(ose.state)}; + + std::list<OmpStylizedDeclaration> decls; + for (auto [type, var] : llvm::zip_equal(types, vars)) { + decls.emplace_back(OmpStylizedDeclaration{ + common::Reference(*type), MakeEntityDecl(Name{var})}); + } + + if (auto &&instance{Parser<OmpStylizedInstance::Instance>{}.Parse(state)}) { + ose.v.emplace_back( + OmpStylizedInstance{std::move(decls), std::move(*instance)}); + } +} + +static void InstantiateForTypes(OmpStylizedExpression &ose, + const OmpTypeNameList &typeNames, llvm::ArrayRef<CharBlock> vars) { + // For each type in the type list, declare all variables in vars with + // that type, and complete the instantiation. + for (const OmpTypeName &t : typeNames.v) { + std::vector<const OmpTypeName *> types(vars.size(), &t); + Instantiate(ose, types, vars); + } +} + +static void InstantiateDeclareReduction(OmpDirectiveSpecification &spec) { + // There can be arguments/clauses that don't make sense, that analysis + // is left until semantic checks. Tolerate any unexpected stuff. + auto *rspec{GetFirstArgument<OmpReductionSpecifier>(spec)}; + if (!rspec) { + return; + } + + const OmpTypeNameList *typeNames{nullptr}; + + if (auto *cexpr{GetCombinerExpr(*rspec)}) { + typeNames = &std::get<OmpTypeNameList>(rspec->t); + + InstantiateForTypes(const_cast<OmpCombinerExpression &>(*cexpr), *typeNames, + OmpCombinerExpression::Variables()); + delete cexpr->state; + } else { + // If there are no types, there is nothing else to do. + return; + } + + for (const OmpClause &clause : spec.Clauses().v) { + llvm::omp::Clause id{clause.Id()}; + if (id == llvm::omp::Clause::OMPC_initializer) { + if (auto *iexpr{GetInitializerExpr(clause)}) { + InstantiateForTypes(const_cast<OmpInitializerExpression &>(*iexpr), + *typeNames, OmpInitializerExpression::Variables()); + delete iexpr->state; + } + } + } +} + +static void InstantiateStylizedDirective(OmpDirectiveSpecification &spec) { + const OmpDirectiveName &dirName{spec.DirName()}; + if (dirName.v == llvm::omp::Directive::OMPD_declare_reduction) { + InstantiateDeclareReduction(spec); + } +} + +template <typename P, + typename = std::enable_if_t< + std::is_same_v<typename P::resultType, OmpDirectiveSpecification>>> +struct OmpStylizedInstanceCreator { + using resultType = OmpDirectiveSpecification; + constexpr OmpStylizedInstanceCreator(P p) : parser_(p) {} + + std::optional<resultType> Parse(ParseState &state) const { + if (auto &&spec{parser_.Parse(state)}) { + InstantiateStylizedDirective(*spec); + return std::move(spec); + } + return std::nullopt; + } + +private: + const P parser_; +}; + +template <typename P> +OmpStylizedInstanceCreator(P) -> OmpStylizedInstanceCreator<P>; + +// --- Parsers for types ---------------------------------------------- + +TYPE_PARSER( // + sourced(construct<OmpTypeName>(Parser<DeclarationTypeSpec>{})) || + sourced(construct<OmpTypeName>(Parser<TypeSpec>{}))) + // --- Parsers for arguments ------------------------------------------ // At the moment these are only directive arguments. This is needed for @@ -366,10 +570,6 @@ struct OmpArgumentListParser { } }; -TYPE_PARSER( // - construct<OmpTypeName>(Parser<DeclarationTypeSpec>{}) || - construct<OmpTypeName>(Parser<TypeSpec>{})) - // 2.15.3.6 REDUCTION (reduction-identifier: variable-name-list) TYPE_PARSER(construct<OmpReductionIdentifier>(Parser<DefinedOperator>{}) || construct<OmpReductionIdentifier>(Parser<ProcedureDesignator>{})) @@ -1065,7 +1265,8 @@ TYPE_PARSER(construct<OmpOtherwiseClause>( TYPE_PARSER(construct<OmpWhenClause>( maybe(nonemptyList(Parser<OmpWhenClause::Modifier>{}) / ":"), - maybe(indirect(Parser<OmpDirectiveSpecification>{})))) + maybe(indirect( + OmpStylizedInstanceCreator(Parser<OmpDirectiveSpecification>{}))))) // OMP 5.2 12.6.1 grainsize([ prescriptiveness :] scalar-integer-expression) TYPE_PARSER(construct<OmpGrainsizeClause>( @@ -1777,12 +1978,7 @@ TYPE_PARSER( Parser<OpenMPInteropConstruct>{})) / endOfLine) -TYPE_PARSER(construct<OmpInitializerProc>(Parser<ProcedureDesignator>{}, - parenthesized(many(maybe(","_tok) >> Parser<ActualArgSpec>{})))) - -TYPE_PARSER(construct<OmpInitializerClause>( - construct<OmpInitializerClause>(assignmentStmt) || - construct<OmpInitializerClause>(Parser<OmpInitializerProc>{}))) +TYPE_PARSER(construct<OmpInitializerClause>(Parser<OmpInitializerExpression>{})) // OpenMP 5.2: 7.5.4 Declare Variant directive TYPE_PARSER(sourced(construct<OmpDeclareVariantDirective>( @@ -1794,7 +1990,7 @@ TYPE_PARSER(sourced(construct<OmpDeclareVariantDirective>( TYPE_PARSER(sourced(construct<OpenMPDeclareReductionConstruct>( predicated(Parser<OmpDirectiveName>{}, IsDirective(llvm::omp::Directive::OMPD_declare_reduction)) >= - Parser<OmpDirectiveSpecification>{}))) + OmpStylizedInstanceCreator(Parser<OmpDirectiveSpecification>{})))) // 2.10.6 Declare Target Construct TYPE_PARSER(sourced(construct<OpenMPDeclareTargetConstruct>( @@ -1832,8 +2028,8 @@ TYPE_PARSER(sourced(construct<OpenMPDeclareMapperConstruct>( IsDirective(llvm::omp::Directive::OMPD_declare_mapper)) >= Parser<OmpDirectiveSpecification>{}))) -TYPE_PARSER(construct<OmpCombinerExpression>(Parser<AssignmentStmt>{}) || - construct<OmpCombinerExpression>(Parser<FunctionReference>{})) +TYPE_PARSER(construct<OmpCombinerExpression>(OmpStylizedExpressionParser{})) +TYPE_PARSER(construct<OmpInitializerExpression>(OmpStylizedExpressionParser{})) TYPE_PARSER(sourced(construct<OpenMPCriticalConstruct>( OmpBlockConstructParser{llvm::omp::Directive::OMPD_critical}))) diff --git a/flang/lib/Parser/openmp-utils.cpp b/flang/lib/Parser/openmp-utils.cpp index 937a17f29f221..95ad3f60770f5 100644 --- a/flang/lib/Parser/openmp-utils.cpp +++ b/flang/lib/Parser/openmp-utils.cpp @@ -74,4 +74,16 @@ const BlockConstruct *GetFortranBlockConstruct( return nullptr; } +const OmpCombinerExpression *GetCombinerExpr( + const OmpReductionSpecifier &rspec) { + return addr_if(std::get<std::optional<OmpCombinerExpression>>(rspec.t)); +} + +const OmpInitializerExpression *GetInitializerExpr(const OmpClause &init) { + if (auto *wrapped{std::get_if<OmpClause::Initializer>(&init.u)}) { + return &wrapped->v.v; + } + return nullptr; +} + } // namespace Fortran::parser::omp diff --git a/flang/lib/Parser/parse-tree.cpp b/flang/lib/Parser/parse-tree.cpp index 8cbaa399c4763..ad0016e1404f9 100644 --- a/flang/lib/Parser/parse-tree.cpp +++ b/flang/lib/Parser/parse-tree.cpp @@ -11,6 +11,7 @@ #include "flang/Common/indirection.h" #include "flang/Parser/tools.h" #include "flang/Parser/user-state.h" +#include "llvm/ADT/ArrayRef.h" #include "llvm/Frontend/OpenMP/OMP.h" #include "llvm/Support/raw_ostream.h" #include <algorithm> @@ -430,4 +431,30 @@ const OmpClauseList &OmpDirectiveSpecification::Clauses() const { ... [truncated] |
tblah reviewed Oct 27, 2025
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Thanks. I prefer this approach. Just some minor comments.
Co-authored-by: Tom Eccles <tom.eccles@arm.com>
Co-authored-by: Tom Eccles <tom.eccles@arm.com>
tblah approved these changes Oct 28, 2025
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Looks great to me. Thanks for the updates.
aokblast pushed a commit to aokblast/llvm-project that referenced this pull request Oct 30, 2025
Consider OpenMP stylized expression to be a template to be instantiated with a series of types listed on the containing directive (currently DECLARE_REDUCTION). Create a series of instantiations in the parser, allowing OpenMP special variables to be declared separately for each type. --------- Co-authored-by: Tom Eccles <tom.eccles@arm.com>
DEBADRIBASAK pushed a commit to DEBADRIBASAK/llvm-project that referenced this pull request Nov 3, 2025
Consider OpenMP stylized expression to be a template to be instantiated with a series of types listed on the containing directive (currently DECLARE_REDUCTION). Create a series of instantiations in the parser, allowing OpenMP special variables to be declared separately for each type. --------- Co-authored-by: Tom Eccles <tom.eccles@arm.com>
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Consider OpenMP stylized expression to be a template to be instantiated with a series of types listed on the containing directive (currently DECLARE_REDUCTION). Create a series of instantiations in the parser, allowing OpenMP special variables to be declared separately for each type.