source: src/SymTab/Mangler.cc @ e580aa5

//
// Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
//
// Mangler.cc --
//
// Author           : Richard C. Bilson
// Created On       : Sun May 17 21:40:29 2015
// Last Modified By : Andrew Beach
// Last Modified On : Fri Oct 21 16:18:00 2022
// Update Count     : 75
//
#include "Mangler.h"

#include <algorithm>                     // for copy, transform
#include <cassert>                       // for assert, assertf
#include <functional>                    // for const_mem_fun_t, mem_fun
#include <iterator>                      // for ostream_iterator, back_insert_ite...
#include <list>                          // for _List_iterator, list, _List_const...
#include <string>                        // for string, char_traits, operator<<

#include "AST/Pass.hpp"
#include "CodeGen/OperatorTable.h"       // for OperatorInfo, operatorLookup
#include "Common/ToString.hpp"           // for toCString
#include "Common/SemanticError.h"        // for SemanticError

namespace Mangle {
        namespace {
                /// Mangles names to a unique C identifier
                struct Mangler : public ast::WithShortCircuiting, public ast::WithVisitorRef<Mangler>, public ast::WithGuards {
                        Mangler( Mangle::Mode mode );
                        Mangler( const Mangler & ) = delete;

                        void previsit( const ast::Node * ) { visit_children = false; }

                        void postvisit( const ast::ObjectDecl * declaration );
                        void postvisit( const ast::FunctionDecl * declaration );
                        void postvisit( const ast::TypeDecl * declaration );

                        void postvisit( const ast::VoidType * voidType );
                        void postvisit( const ast::BasicType * basicType );
                        void postvisit( const ast::PointerType * pointerType );
                        void postvisit( const ast::ArrayType * arrayType );
                        void postvisit( const ast::ReferenceType * refType );
                        void postvisit( const ast::FunctionType * functionType );
                        void postvisit( const ast::StructInstType * aggregateUseType );
                        void postvisit( const ast::UnionInstType * aggregateUseType );
                        void postvisit( const ast::EnumInstType * aggregateUseType );
                        void postvisit( const ast::TypeInstType * aggregateUseType );
                        void postvisit( const ast::TraitInstType * inst );
                        void postvisit( const ast::TupleType * tupleType );
                        void postvisit( const ast::VarArgsType * varArgsType );
                        void postvisit( const ast::ZeroType * zeroType );
                        void postvisit( const ast::OneType * oneType );
                        void postvisit( const ast::QualifiedType * qualType );

                        /// The result is the current constructed mangled name.
                        std::string result() const { return mangleName; }
                  private:
                        std::string mangleName;         ///< Mangled name being constructed
                        typedef std::map< std::string, std::pair< int, int > > VarMapType;
                        VarMapType varNums;             ///< Map of type variables to indices
                        int nextVarNum;                 ///< Next type variable index
                        bool isTopLevel;                ///< Is the Mangler at the top level
                        bool mangleOverridable;         ///< Specially mangle overridable built-in methods
                        bool typeMode;                  ///< Produce a unique mangled name for a type
                        bool mangleGenericParams;       ///< Include generic parameters in name mangling if true
                        bool inFunctionType = false;    ///< Include type qualifiers if false.
                        bool inQualifiedType = false;   ///< Add start/end delimiters around qualified type

                  private:
                        Mangler( bool mangleOverridable, bool typeMode, bool mangleGenericParams,
                                int nextVarNum, const VarMapType& varNums );
                        friend class ast::Pass<Mangler>;

                  private:
                        void mangleDecl( const ast::DeclWithType *declaration );
                        void mangleRef( const ast::BaseInstType *refType, const std::string & prefix );

                        void printQualifiers( const ast::Type *type );
                }; // Mangler
        } // namespace

        std::string mangle( const ast::Node * decl, Mangle::Mode mode ) {
                return ast::Pass<Mangler>::read( decl, mode );
        }

        namespace {
                Mangler::Mangler( Mangle::Mode mode )
                        : nextVarNum( 0 ), isTopLevel( true ),
                        mangleOverridable  ( ! mode.no_overrideable   ),
                        typeMode           (   mode.type              ),
                        mangleGenericParams( ! mode.no_generic_params ) {}

                Mangler::Mangler( bool mangleOverridable, bool typeMode, bool mangleGenericParams,
                        int nextVarNum, const VarMapType& varNums )
                        : varNums( varNums ), nextVarNum( nextVarNum ), isTopLevel( false ),
                        mangleOverridable( mangleOverridable ), typeMode( typeMode ),
                        mangleGenericParams( mangleGenericParams ) {}

                void Mangler::mangleDecl( const ast::DeclWithType * decl ) {
                        bool wasTopLevel = isTopLevel;
                        if ( isTopLevel ) {
                                varNums.clear();
                                nextVarNum = 0;
                                isTopLevel = false;
                        } // if
                        mangleName += Encoding::manglePrefix;
                        const CodeGen::OperatorInfo * opInfo = CodeGen::operatorLookup( decl->name );
                        if ( opInfo ) {
                                mangleName += std::to_string( opInfo->outputName.size() ) + opInfo->outputName;
                        } else {
                                mangleName += std::to_string( decl->name.size() ) + decl->name;
                        } // if
                        decl->get_type()->accept( *visitor );
                        if ( mangleOverridable && decl->linkage.is_overrideable ) {
                                // want to be able to override autogenerated and intrinsic routines,
                                // so they need a different name mangling
                                if ( decl->linkage == ast::Linkage::AutoGen ) {
                                        mangleName += Encoding::autogen;
                                } else if ( decl->linkage == ast::Linkage::Intrinsic ) {
                                        mangleName += Encoding::intrinsic;
                                } else {
                                        // if we add another kind of overridable function, this has to change
                                        assert( false && "unknown overrideable linkage" );
                                } // if
                        }
                        isTopLevel = wasTopLevel;
                }

                void Mangler::postvisit( const ast::ObjectDecl * decl ) {
                        mangleDecl( decl );
                }

                void Mangler::postvisit( const ast::FunctionDecl * decl ) {
                        mangleDecl( decl );
                }

                void Mangler::postvisit( const ast::VoidType * voidType ) {
                        printQualifiers( voidType );
                        mangleName += Encoding::void_t;
                }

                void Mangler::postvisit( const ast::BasicType * basicType ) {
                        printQualifiers( basicType );
                        assertf( basicType->kind < ast::BasicType::NUMBER_OF_BASIC_TYPES, "Unhandled basic type: %d", basicType->kind );
                        mangleName += Encoding::basicTypes[ basicType->kind ];
                }

                void Mangler::postvisit( const ast::PointerType * pointerType ) {
                        printQualifiers( pointerType );
                        // mangle void (*f)() and void f() to the same name to prevent overloading on functions and function pointers
                        if ( ! pointerType->base.as<ast::FunctionType>() ) mangleName += Encoding::pointer;
                        maybe_accept( pointerType->base.get(), *visitor );
                }

                void Mangler::postvisit( const ast::ArrayType * arrayType ) {
                        // TODO: encode dimension
                        printQualifiers( arrayType );
                        mangleName += Encoding::array + "0";
                        arrayType->base->accept( *visitor );
                }

                void Mangler::postvisit( const ast::ReferenceType * refType ) {
                        // don't print prefix (e.g. 'R') for reference types so that references and non-references do not overload.
                        // Further, do not print the qualifiers for a reference type (but do run printQualifers because of TypeDecls, etc.),
                        // by pretending every reference type is a function parameter.
                        GuardValue( inFunctionType );
                        inFunctionType = true;
                        printQualifiers( refType );
                        refType->base->accept( *visitor );
                }

                void Mangler::postvisit( const ast::FunctionType * functionType ) {
                        printQualifiers( functionType );
                        mangleName += Encoding::function;
                        // turn on inFunctionType so that printQualifiers does not print most qualifiers for function parameters,
                        // since qualifiers on outermost parameter type do not differentiate function types, e.g.,
                        // void (*)(const int) and void (*)(int) are the same type, but void (*)(const int *) and void (*)(int *) are different
                        GuardValue( inFunctionType );
                        inFunctionType = true;
                        if (functionType->returns.empty()) mangleName += Encoding::void_t;
                        else accept_each( functionType->returns, *visitor );
                        mangleName += "_";
                        accept_each( functionType->params, *visitor );
                        mangleName += "_";
                }

                void Mangler::mangleRef(
                                const ast::BaseInstType * refType, const std::string & prefix ) {
                        printQualifiers( refType );

                        mangleName += prefix + std::to_string( refType->name.length() ) + refType->name;

                        if ( mangleGenericParams && ! refType->params.empty() ) {
                                mangleName += "_";
                                for ( const ast::Expr * param : refType->params ) {
                                        auto paramType = dynamic_cast< const ast::TypeExpr * >( param );
                                        assertf(paramType, "Aggregate parameters should be type expressions: %s", toCString(param));
                                        paramType->type->accept( *visitor );
                                }
                                mangleName += "_";
                        }
                }

                void Mangler::postvisit( const ast::StructInstType * aggregateUseType ) {
                        mangleRef( aggregateUseType, Encoding::struct_t );
                }

                void Mangler::postvisit( const ast::UnionInstType * aggregateUseType ) {
                        mangleRef( aggregateUseType, Encoding::union_t );
                }

                void Mangler::postvisit( const ast::EnumInstType * aggregateUseType ) {
                        mangleRef( aggregateUseType, Encoding::enum_t );
                }

                void Mangler::postvisit( const ast::TypeInstType * typeInst ) {
                        VarMapType::iterator varNum = varNums.find( typeInst->name );
                        if ( varNum == varNums.end() ) {
                                mangleRef( typeInst, Encoding::type );
                        } else {
                                printQualifiers( typeInst );
                                // Note: Can't use name here, since type variable names do not actually disambiguate a function, e.g.
                                //   forall(dtype T) void f(T);
                                //   forall(dtype S) void f(S);
                                // are equivalent and should mangle the same way. This is accomplished by numbering the type variables when they
                                // are first found and prefixing with the appropriate encoding for the type class.
                                assertf( varNum->second.second < ast::TypeDecl::NUMBER_OF_KINDS, "Unhandled type variable kind: %d", varNum->second.second );
                                mangleName += Encoding::typeVariables[varNum->second.second] + std::to_string( varNum->second.first );
                        } // if
                }

                void Mangler::postvisit( const ast::TraitInstType * inst ) {
                        printQualifiers( inst );
                        mangleName += std::to_string( inst->name.size() ) + inst->name;
                }

                void Mangler::postvisit( const ast::TupleType * tupleType ) {
                        printQualifiers( tupleType );
                        mangleName += Encoding::tuple + std::to_string( tupleType->types.size() );
                        accept_each( tupleType->types, *visitor );
                }

                void Mangler::postvisit( const ast::VarArgsType * varArgsType ) {
                        printQualifiers( varArgsType );
                        static const std::string vargs = "__builtin_va_list";
                        mangleName += Encoding::type + std::to_string( vargs.size() ) + vargs;
                }

                void Mangler::postvisit( const ast::ZeroType * ) {
                        mangleName += Encoding::zero;
                }

                void Mangler::postvisit( const ast::OneType * ) {
                        mangleName += Encoding::one;
                }

                void Mangler::postvisit( const ast::QualifiedType * qualType ) {
                        bool inqual = inQualifiedType;
                        if ( !inqual ) {
                                // N marks the start of a qualified type
                                inQualifiedType = true;
                                mangleName += Encoding::qualifiedTypeStart;
                        }
                        qualType->parent->accept( *visitor );
                        qualType->child->accept( *visitor );
                        if ( !inqual ) {
                                // E marks the end of a qualified type
                                inQualifiedType = false;
                                mangleName += Encoding::qualifiedTypeEnd;
                        }
                }

                void Mangler::postvisit( const ast::TypeDecl * decl ) {
                        // TODO: is there any case where mangling a TypeDecl makes sense? If so, this code needs to be
                        // fixed to ensure that two TypeDecls mangle to the same name when they are the same type and vice versa.
                        // Note: The current scheme may already work correctly for this case, I have not thought about this deeply
                        // and the case has not yet come up in practice. Alternatively, if not then this code can be removed
                        // aside from the assert false.
                        assertf(false, "Mangler should not visit typedecl: %s", toCString(decl));
                        assertf( decl->kind < ast::TypeDecl::Kind::NUMBER_OF_KINDS, "Unhandled type variable kind: %d", decl->kind );
                        mangleName += Encoding::typeVariables[ decl->kind ] + std::to_string( decl->name.length() ) + decl->name;
                }

                // For debugging:
                __attribute__((unused)) void printVarMap( const std::map< std::string, std::pair< int, int > > &varMap, std::ostream &os ) {
                        for ( std::map< std::string, std::pair< int, int > >::const_iterator i = varMap.begin(); i != varMap.end(); ++i ) {
                                os << i->first << "(" << i->second.first << "/" << i->second.second << ")" << std::endl;
                        } // for
                }

                void Mangler::printQualifiers( const ast::Type * type ) {
                        // skip if not including qualifiers
                        if ( typeMode ) return;
                        auto funcType = dynamic_cast<const ast::FunctionType *>( type );
                        if ( funcType && !funcType->forall.empty() ) {
                                std::list< std::string > assertionNames;
                                int dcount = 0, fcount = 0, vcount = 0, acount = 0;
                                mangleName += Encoding::forall;
                                for ( auto & decl : funcType->forall ) {
                                        switch ( decl->kind ) {
                                        case ast::TypeDecl::Dtype:
                                                dcount++;
                                                break;
                                        case ast::TypeDecl::Ftype:
                                                fcount++;
                                                break;
                                        case ast::TypeDecl::Ttype:
                                                vcount++;
                                                break;
                                        default:
                                                assertf( false, "unimplemented kind for type variable %s", SymTab::Mangler::Encoding::typeVariables[decl->kind].c_str() );
                                        } // switch
                                        varNums[ decl->name ] = std::make_pair( nextVarNum, (int)decl->kind );
                                } // for
                                for ( auto & assert : funcType->assertions ) {
                                        assertionNames.push_back( ast::Pass<Mangler>::read(
                                                assert->var.get(),
                                                mangleOverridable, typeMode, mangleGenericParams, nextVarNum, varNums ) );
                                        acount++;
                                } // for
                                mangleName += std::to_string( dcount ) + "_" + std::to_string( fcount ) + "_" + std::to_string( vcount ) + "_" + std::to_string( acount ) + "_";
                                for ( const auto & a : assertionNames ) mangleName += a;
                                mangleName += "_";
                        } // if
                        if ( ! inFunctionType ) {
                                // these qualifiers do not distinguish the outermost type of a function parameter
                                if ( type->is_const() ) {
                                        mangleName += Encoding::qualifiers.at( ast::CV::Const );
                                } // if
                                if ( type->is_volatile() ) {
                                        mangleName += Encoding::qualifiers.at( ast::CV::Volatile );
                                } // if
                                // Removed due to restrict not affecting function compatibility in GCC
                                // if ( type->get_isRestrict() ) {
                                //      mangleName += "E";
                                // } // if
                                if ( type->is_atomic() ) {
                                        mangleName += Encoding::qualifiers.at( ast::CV::Atomic );
                                } // if
                        }
                        if ( type->is_mutex() ) {
                                mangleName += Encoding::qualifiers.at( ast::CV::Mutex );
                        } // if
                        if ( inFunctionType ) {
                                // turn off inFunctionType so that types can be differentiated for nested qualifiers
                                GuardValue( inFunctionType );
                                inFunctionType = false;
                        }
                }
        }       // namespace
} // namespace Mangle

// Local Variables: //
// tab-width: 4 //
// mode: c++ //
// compile-command: "make install" //
// End: //