[a32b204] | 1 | // |
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| 2 | // Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo |
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| 3 | // |
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| 4 | // The contents of this file are covered under the licence agreement in the |
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| 5 | // file "LICENCE" distributed with Cforall. |
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| 6 | // |
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[41a2620] | 7 | // Unify.cc -- |
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[a32b204] | 8 | // |
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| 9 | // Author : Richard C. Bilson |
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| 10 | // Created On : Sun May 17 12:27:10 2015 |
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[07de76b] | 11 | // Last Modified By : Peter A. Buhr |
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| 12 | // Last Modified On : Fri Dec 13 23:43:05 2019 |
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| 13 | // Update Count : 46 |
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[a32b204] | 14 | // |
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[51b7345] | 15 | |
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[f474e91] | 16 | #include "Unify.h" |
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| 17 | |
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[d76c588] | 18 | #include <cassert> // for assertf, assert |
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| 19 | #include <iterator> // for back_insert_iterator, back_inserter |
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| 20 | #include <map> // for _Rb_tree_const_iterator, _Rb_tree_i... |
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| 21 | #include <memory> // for unique_ptr |
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| 22 | #include <set> // for set |
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| 23 | #include <string> // for string, operator==, operator!=, bas... |
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| 24 | #include <utility> // for pair, move |
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[54e41b3] | 25 | #include <vector> |
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[51b7345] | 26 | |
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[2890212] | 27 | #include "AST/Copy.hpp" |
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[f474e91] | 28 | #include "AST/Decl.hpp" |
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[54e41b3] | 29 | #include "AST/Node.hpp" |
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[f474e91] | 30 | #include "AST/Pass.hpp" |
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[2890212] | 31 | #include "AST/Print.hpp" |
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[54e41b3] | 32 | #include "AST/Type.hpp" |
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[d76c588] | 33 | #include "AST/TypeEnvironment.hpp" |
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[f02f546] | 34 | #include "Common/Eval.h" // for eval |
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[5bf3976] | 35 | #include "CommonType.hpp" // for commonType |
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[d76c588] | 36 | #include "FindOpenVars.h" // for findOpenVars |
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[5bf3976] | 37 | #include "SpecCost.hpp" // for SpecCost |
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[d76c588] | 38 | #include "Tuples/Tuples.h" // for isTtype |
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[5bf3976] | 39 | #include "typeops.h" // for flatten, occurs |
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[ea6332d] | 40 | |
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[f474e91] | 41 | namespace ast { |
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| 42 | class SymbolTable; |
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| 43 | } |
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| 44 | |
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[1cbca6e] | 45 | // #define DEBUG |
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[51b7345] | 46 | |
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| 47 | namespace ResolvExpr { |
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| 48 | |
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[7870799] | 49 | bool typesCompatible( |
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[251ce80] | 50 | const ast::Type * first, const ast::Type * second, |
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[d76c588] | 51 | const ast::TypeEnvironment & env ) { |
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[f474e91] | 52 | ast::TypeEnvironment newEnv; |
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| 53 | ast::OpenVarSet open, closed; |
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| 54 | ast::AssertionSet need, have; |
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| 55 | |
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| 56 | ast::ptr<ast::Type> newFirst{ first }, newSecond{ second }; |
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| 57 | env.apply( newFirst ); |
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| 58 | env.apply( newSecond ); |
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| 59 | |
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[46da46b] | 60 | // findOpenVars( newFirst, open, closed, need, have, FirstClosed ); |
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| 61 | findOpenVars( newSecond, open, closed, need, have, newEnv, FirstOpen ); |
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[f474e91] | 62 | |
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[251ce80] | 63 | return unifyExact(newFirst, newSecond, newEnv, need, have, open, noWiden() ); |
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[d76c588] | 64 | } |
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| 65 | |
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[7870799] | 66 | bool typesCompatibleIgnoreQualifiers( |
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[251ce80] | 67 | const ast::Type * first, const ast::Type * second, |
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[d76c588] | 68 | const ast::TypeEnvironment & env ) { |
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[f474e91] | 69 | ast::TypeEnvironment newEnv; |
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| 70 | ast::OpenVarSet open; |
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| 71 | ast::AssertionSet need, have; |
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[7870799] | 72 | |
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[2890212] | 73 | ast::Type * newFirst = shallowCopy( first ); |
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| 74 | ast::Type * newSecond = shallowCopy( second ); |
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[b729c01] | 75 | if ( auto temp = dynamic_cast<const ast::EnumInstType *>(first) ) { |
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| 76 | if ( !dynamic_cast< const ast::EnumInstType * >( second ) ) { |
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| 77 | const ast::EnumDecl * baseEnum = dynamic_cast<const ast::EnumDecl *>(temp->base.get()); |
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| 78 | if ( auto t = baseEnum->base.get() ) { |
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| 79 | newFirst = ast::shallowCopy( t ); |
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| 80 | } |
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| 81 | } |
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| 82 | } else if ( auto temp = dynamic_cast<const ast::EnumInstType *>(second) ) { |
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| 83 | const ast::EnumDecl * baseEnum = dynamic_cast<const ast::EnumDecl *>(temp->base.get()); |
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| 84 | if ( auto t = baseEnum->base.get() ) { |
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| 85 | newSecond = ast::shallowCopy( t ); |
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| 86 | } |
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| 87 | } |
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| 88 | |
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[2890212] | 89 | newFirst ->qualifiers = {}; |
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| 90 | newSecond->qualifiers = {}; |
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[f49b3fc] | 91 | ast::ptr< ast::Type > t1_(newFirst ); |
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| 92 | ast::ptr< ast::Type > t2_(newSecond); |
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[f474e91] | 93 | |
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[c7f834e] | 94 | ast::ptr< ast::Type > subFirst = env.apply(newFirst).node; |
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| 95 | ast::ptr< ast::Type > subSecond = env.apply(newSecond).node; |
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| 96 | |
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[7870799] | 97 | return unifyExact( |
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[c7f834e] | 98 | subFirst, |
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| 99 | subSecond, |
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[251ce80] | 100 | newEnv, need, have, open, noWiden() ); |
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[d76c588] | 101 | } |
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| 102 | |
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[ef1da0e2] | 103 | namespace { |
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| 104 | /// Replaces ttype variables with their bound types. |
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| 105 | /// If this isn't done when satifying ttype assertions, then argument lists can have |
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| 106 | /// different size and structure when they should be compatible. |
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[0bd3faf] | 107 | struct TtypeExpander : public ast::WithShortCircuiting, public ast::PureVisitor { |
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[ef1da0e2] | 108 | ast::TypeEnvironment & tenv; |
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| 109 | |
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[0bd3faf] | 110 | TtypeExpander( ast::TypeEnvironment & env ) : tenv( env ) {} |
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[ef1da0e2] | 111 | |
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| 112 | const ast::Type * postvisit( const ast::TypeInstType * typeInst ) { |
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| 113 | if ( const ast::EqvClass * clz = tenv.lookup( *typeInst ) ) { |
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| 114 | // expand ttype parameter into its actual type |
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| 115 | if ( clz->data.kind == ast::TypeDecl::Ttype && clz->bound ) { |
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| 116 | return clz->bound; |
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| 117 | } |
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| 118 | } |
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| 119 | return typeInst; |
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| 120 | } |
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| 121 | }; |
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| 122 | } |
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[0bd46fd] | 123 | |
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[ef1da0e2] | 124 | std::vector< ast::ptr< ast::Type > > flattenList( |
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| 125 | const std::vector< ast::ptr< ast::Type > > & src, ast::TypeEnvironment & env |
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| 126 | ) { |
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| 127 | std::vector< ast::ptr< ast::Type > > dst; |
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| 128 | dst.reserve( src.size() ); |
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| 129 | for ( const auto & d : src ) { |
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[0bd3faf] | 130 | ast::Pass<TtypeExpander> expander{ env }; |
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[ef1da0e2] | 131 | // TtypeExpander pass is impure (may mutate nodes in place) |
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| 132 | // need to make nodes shared to prevent accidental mutation |
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| 133 | ast::ptr<ast::Type> dc = d->accept(expander); |
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| 134 | auto types = flatten( dc ); |
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| 135 | for ( ast::ptr< ast::Type > & t : types ) { |
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| 136 | // outermost const, volatile, _Atomic qualifiers in parameters should not play |
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| 137 | // a role in the unification of function types, since they do not determine |
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| 138 | // whether a function is callable. |
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| 139 | // NOTE: **must** consider at least mutex qualifier, since functions can be |
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| 140 | // overloaded on outermost mutex and a mutex function has different |
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| 141 | // requirements than a non-mutex function |
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| 142 | remove_qualifiers( t, ast::CV::Const | ast::CV::Volatile | ast::CV::Atomic ); |
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| 143 | dst.emplace_back( t ); |
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| 144 | } |
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| 145 | } |
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| 146 | return dst; |
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| 147 | } |
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| 148 | |
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[f02f546] | 149 | // Unification of Expressions |
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| 150 | // |
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| 151 | // Boolean outcome (obvious): Are they basically spelled the same? |
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| 152 | // Side effect of binding variables (subtle): if `sizeof(int)` ===_expr `sizeof(T)` then `int` ===_ty `T` |
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| 153 | // |
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| 154 | // Context: if `float[VAREXPR1]` ===_ty `float[VAREXPR2]` then `VAREXPR1` ===_expr `VAREXPR2` |
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| 155 | // where the VAREXPR are meant as notational metavariables representing the fact that unification always |
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| 156 | // sees distinct ast::VariableExpr objects at these positions |
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| 157 | |
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| 158 | static bool unify( const ast::Expr * e1, const ast::Expr * e2, ast::TypeEnvironment & env, |
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| 159 | ast::AssertionSet & need, ast::AssertionSet & have, const ast::OpenVarSet & open, |
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| 160 | WidenMode widen ); |
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| 161 | |
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| 162 | class UnifyExpr final : public ast::WithShortCircuiting { |
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| 163 | const ast::Expr * e2; |
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| 164 | ast::TypeEnvironment & tenv; |
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| 165 | ast::AssertionSet & need; |
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| 166 | ast::AssertionSet & have; |
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| 167 | const ast::OpenVarSet & open; |
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| 168 | WidenMode widen; |
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| 169 | public: |
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| 170 | bool result; |
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| 171 | |
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| 172 | private: |
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| 173 | |
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| 174 | void tryMatchOnStaticValue( const ast::Expr * e1 ) { |
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| 175 | Evaluation r1 = eval(e1); |
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| 176 | Evaluation r2 = eval(e2); |
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| 177 | |
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| 178 | if ( ! r1.hasKnownValue ) return; |
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| 179 | if ( ! r2.hasKnownValue ) return; |
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| 180 | |
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| 181 | if (r1.knownValue != r2.knownValue) return; |
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| 182 | |
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| 183 | visit_children = false; |
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| 184 | result = true; |
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| 185 | } |
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| 186 | |
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| 187 | public: |
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| 188 | |
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| 189 | void previsit( const ast::Node * ) { assert(false); } |
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| 190 | |
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| 191 | void previsit( const ast::Expr * e1 ) { |
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| 192 | tryMatchOnStaticValue( e1 ); |
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| 193 | visit_children = false; |
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| 194 | } |
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| 195 | |
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| 196 | void previsit( const ast::CastExpr * e1 ) { |
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| 197 | tryMatchOnStaticValue( e1 ); |
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| 198 | |
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| 199 | if (result) { |
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| 200 | assert (visit_children == false); |
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| 201 | } else { |
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| 202 | assert (visit_children == true); |
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| 203 | visit_children = false; |
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| 204 | |
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| 205 | auto e2c = dynamic_cast< const ast::CastExpr * >( e2 ); |
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| 206 | if ( ! e2c ) return; |
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| 207 | |
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| 208 | // inspect casts' target types |
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| 209 | if ( ! unifyExact( |
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| 210 | e1->result, e2c->result, tenv, need, have, open, widen ) ) return; |
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| 211 | |
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| 212 | // inspect casts' inner expressions |
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| 213 | result = unify( e1->arg, e2c->arg, tenv, need, have, open, widen ); |
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| 214 | } |
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| 215 | } |
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| 216 | |
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| 217 | void previsit( const ast::VariableExpr * e1 ) { |
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| 218 | tryMatchOnStaticValue( e1 ); |
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| 219 | |
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| 220 | if (result) { |
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| 221 | assert (visit_children == false); |
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| 222 | } else { |
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| 223 | assert (visit_children == true); |
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| 224 | visit_children = false; |
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| 225 | |
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| 226 | auto e2v = dynamic_cast< const ast::VariableExpr * >( e2 ); |
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| 227 | if ( ! e2v ) return; |
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| 228 | |
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| 229 | assert(e1->var); |
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| 230 | assert(e2v->var); |
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| 231 | |
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| 232 | // conservative: variable exprs match if their declarations are represented by the same C++ AST object |
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| 233 | result = (e1->var == e2v->var); |
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| 234 | } |
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| 235 | } |
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| 236 | |
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| 237 | void previsit( const ast::SizeofExpr * e1 ) { |
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| 238 | tryMatchOnStaticValue( e1 ); |
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| 239 | |
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| 240 | if (result) { |
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| 241 | assert (visit_children == false); |
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| 242 | } else { |
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| 243 | assert (visit_children == true); |
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| 244 | visit_children = false; |
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| 245 | |
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| 246 | auto e2so = dynamic_cast< const ast::SizeofExpr * >( e2 ); |
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| 247 | if ( ! e2so ) return; |
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| 248 | |
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| 249 | assert((e1->type != nullptr) ^ (e1->expr != nullptr)); |
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| 250 | assert((e2so->type != nullptr) ^ (e2so->expr != nullptr)); |
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| 251 | if ( ! (e1->type && e2so->type) ) return; |
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| 252 | |
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| 253 | // expression unification calls type unification (mutual recursion) |
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| 254 | result = unifyExact( e1->type, e2so->type, tenv, need, have, open, widen ); |
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| 255 | } |
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| 256 | } |
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| 257 | |
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| 258 | UnifyExpr( const ast::Expr * e2, ast::TypeEnvironment & env, ast::AssertionSet & need, |
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| 259 | ast::AssertionSet & have, const ast::OpenVarSet & open, WidenMode widen ) |
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| 260 | : e2( e2 ), tenv(env), need(need), have(have), open(open), widen(widen), result(false) {} |
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| 261 | }; |
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| 262 | |
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| 263 | static bool unify( const ast::Expr * e1, const ast::Expr * e2, ast::TypeEnvironment & env, |
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| 264 | ast::AssertionSet & need, ast::AssertionSet & have, const ast::OpenVarSet & open, |
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| 265 | WidenMode widen ) { |
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| 266 | assert( e1 && e2 ); |
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| 267 | return ast::Pass<UnifyExpr>::read( e1, e2, env, need, have, open, widen ); |
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| 268 | } |
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| 269 | |
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[0bd3faf] | 270 | class Unify final : public ast::WithShortCircuiting { |
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[f474e91] | 271 | const ast::Type * type2; |
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| 272 | ast::TypeEnvironment & tenv; |
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| 273 | ast::AssertionSet & need; |
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| 274 | ast::AssertionSet & have; |
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| 275 | const ast::OpenVarSet & open; |
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| 276 | WidenMode widen; |
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| 277 | public: |
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[c15085d] | 278 | static size_t traceId; |
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[f474e91] | 279 | bool result; |
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| 280 | |
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[0bd3faf] | 281 | Unify( |
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[7870799] | 282 | const ast::Type * type2, ast::TypeEnvironment & env, ast::AssertionSet & need, |
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[251ce80] | 283 | ast::AssertionSet & have, const ast::OpenVarSet & open, WidenMode widen ) |
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[7870799] | 284 | : type2(type2), tenv(env), need(need), have(have), open(open), widen(widen), |
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[251ce80] | 285 | result(false) {} |
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[f474e91] | 286 | |
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| 287 | void previsit( const ast::Node * ) { visit_children = false; } |
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[7870799] | 288 | |
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[ee574a2] | 289 | void postvisit( const ast::VoidType * ) { |
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[f474e91] | 290 | result = dynamic_cast< const ast::VoidType * >( type2 ); |
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| 291 | } |
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| 292 | |
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[ee574a2] | 293 | void postvisit( const ast::BasicType * basic ) { |
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[f474e91] | 294 | if ( auto basic2 = dynamic_cast< const ast::BasicType * >( type2 ) ) { |
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| 295 | result = basic->kind == basic2->kind; |
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| 296 | } |
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| 297 | } |
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| 298 | |
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[ee574a2] | 299 | void postvisit( const ast::PointerType * pointer ) { |
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[f474e91] | 300 | if ( auto pointer2 = dynamic_cast< const ast::PointerType * >( type2 ) ) { |
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[7870799] | 301 | result = unifyExact( |
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| 302 | pointer->base, pointer2->base, tenv, need, have, open, |
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[251ce80] | 303 | noWiden()); |
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[f474e91] | 304 | } |
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| 305 | } |
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| 306 | |
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[ee574a2] | 307 | void postvisit( const ast::ArrayType * array ) { |
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[f474e91] | 308 | auto array2 = dynamic_cast< const ast::ArrayType * >( type2 ); |
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| 309 | if ( ! array2 ) return; |
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| 310 | |
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| 311 | if ( array->isVarLen != array2->isVarLen ) return; |
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[f02f546] | 312 | if ( (array->dimension != nullptr) != (array2->dimension != nullptr) ) return; |
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[f474e91] | 313 | |
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[f02f546] | 314 | if ( array->dimension ) { |
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| 315 | assert( array2->dimension ); |
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| 316 | // type unification calls expression unification (mutual recursion) |
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| 317 | if ( ! unify(array->dimension, array2->dimension, |
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| 318 | tenv, need, have, open, widen) ) return; |
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[f474e91] | 319 | } |
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| 320 | |
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[7870799] | 321 | result = unifyExact( |
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[251ce80] | 322 | array->base, array2->base, tenv, need, have, open, noWiden()); |
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[f474e91] | 323 | } |
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| 324 | |
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[ee574a2] | 325 | void postvisit( const ast::ReferenceType * ref ) { |
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[f474e91] | 326 | if ( auto ref2 = dynamic_cast< const ast::ReferenceType * >( type2 ) ) { |
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[7870799] | 327 | result = unifyExact( |
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[251ce80] | 328 | ref->base, ref2->base, tenv, need, have, open, noWiden()); |
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[f474e91] | 329 | } |
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| 330 | } |
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| 331 | |
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| 332 | private: |
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| 333 | |
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| 334 | template< typename Iter > |
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[954c954] | 335 | static bool unifyTypeList( |
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[7870799] | 336 | Iter crnt1, Iter end1, Iter crnt2, Iter end2, ast::TypeEnvironment & env, |
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[251ce80] | 337 | ast::AssertionSet & need, ast::AssertionSet & have, const ast::OpenVarSet & open |
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[f474e91] | 338 | ) { |
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| 339 | while ( crnt1 != end1 && crnt2 != end2 ) { |
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[954c954] | 340 | const ast::Type * t1 = *crnt1; |
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| 341 | const ast::Type * t2 = *crnt2; |
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[f474e91] | 342 | bool isTuple1 = Tuples::isTtype( t1 ); |
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| 343 | bool isTuple2 = Tuples::isTtype( t2 ); |
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| 344 | |
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| 345 | // assumes here that ttype *must* be last parameter |
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| 346 | if ( isTuple1 && ! isTuple2 ) { |
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| 347 | // combine remainder of list2, then unify |
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[7870799] | 348 | return unifyExact( |
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[954c954] | 349 | t1, tupleFromTypes( crnt2, end2 ), env, need, have, open, |
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[251ce80] | 350 | noWiden() ); |
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[f474e91] | 351 | } else if ( ! isTuple1 && isTuple2 ) { |
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| 352 | // combine remainder of list1, then unify |
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[7870799] | 353 | return unifyExact( |
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[954c954] | 354 | tupleFromTypes( crnt1, end1 ), t2, env, need, have, open, |
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[251ce80] | 355 | noWiden() ); |
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[f474e91] | 356 | } |
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| 357 | |
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[7870799] | 358 | if ( ! unifyExact( |
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[251ce80] | 359 | t1, t2, env, need, have, open, noWiden() ) |
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[f474e91] | 360 | ) return false; |
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| 361 | |
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| 362 | ++crnt1; ++crnt2; |
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| 363 | } |
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| 364 | |
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[7870799] | 365 | // May get to the end of one argument list before the other. This is only okay if the |
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[f474e91] | 366 | // other is a ttype |
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| 367 | if ( crnt1 != end1 ) { |
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| 368 | // try unifying empty tuple with ttype |
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[954c954] | 369 | const ast::Type * t1 = *crnt1; |
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[f474e91] | 370 | if ( ! Tuples::isTtype( t1 ) ) return false; |
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[7870799] | 371 | return unifyExact( |
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[954c954] | 372 | t1, tupleFromTypes( crnt2, end2 ), env, need, have, open, |
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[251ce80] | 373 | noWiden() ); |
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[f474e91] | 374 | } else if ( crnt2 != end2 ) { |
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| 375 | // try unifying empty tuple with ttype |
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[954c954] | 376 | const ast::Type * t2 = *crnt2; |
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[f474e91] | 377 | if ( ! Tuples::isTtype( t2 ) ) return false; |
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[7870799] | 378 | return unifyExact( |
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[954c954] | 379 | tupleFromTypes( crnt1, end1 ), t2, env, need, have, open, |
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[251ce80] | 380 | noWiden() ); |
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[f474e91] | 381 | } |
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| 382 | |
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| 383 | return true; |
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| 384 | } |
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| 385 | |
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[954c954] | 386 | static bool unifyTypeList( |
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| 387 | const std::vector< ast::ptr< ast::Type > > & list1, |
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| 388 | const std::vector< ast::ptr< ast::Type > > & list2, |
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[7870799] | 389 | ast::TypeEnvironment & env, ast::AssertionSet & need, ast::AssertionSet & have, |
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[251ce80] | 390 | const ast::OpenVarSet & open |
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[f474e91] | 391 | ) { |
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[954c954] | 392 | return unifyTypeList( |
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[251ce80] | 393 | list1.begin(), list1.end(), list2.begin(), list2.end(), env, need, have, open); |
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[f474e91] | 394 | } |
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| 395 | |
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[3e5dd913] | 396 | static void markAssertionSet( ast::AssertionSet & assns, const ast::VariableExpr * assn ) { |
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[f474e91] | 397 | auto i = assns.find( assn ); |
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| 398 | if ( i != assns.end() ) { |
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| 399 | i->second.isUsed = true; |
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| 400 | } |
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| 401 | } |
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| 402 | |
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| 403 | /// mark all assertions in `type` used in both `assn1` and `assn2` |
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[7870799] | 404 | static void markAssertions( |
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| 405 | ast::AssertionSet & assn1, ast::AssertionSet & assn2, |
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[361bf01] | 406 | const ast::FunctionType * type |
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[f474e91] | 407 | ) { |
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[3e5dd913] | 408 | for ( auto & assert : type->assertions ) { |
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| 409 | markAssertionSet( assn1, assert ); |
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| 410 | markAssertionSet( assn2, assert ); |
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[f474e91] | 411 | } |
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| 412 | } |
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| 413 | |
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| 414 | public: |
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[ee574a2] | 415 | void postvisit( const ast::FunctionType * func ) { |
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[f474e91] | 416 | auto func2 = dynamic_cast< const ast::FunctionType * >( type2 ); |
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| 417 | if ( ! func2 ) return; |
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| 418 | |
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| 419 | if ( func->isVarArgs != func2->isVarArgs ) return; |
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[7870799] | 420 | |
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| 421 | // Flatten the parameter lists for both functions so that tuple structure does not |
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[f474e91] | 422 | // affect unification. Does not actually mutate function parameters. |
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| 423 | auto params = flattenList( func->params, tenv ); |
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| 424 | auto params2 = flattenList( func2->params, tenv ); |
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| 425 | |
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[7870799] | 426 | // sizes don't have to match if ttypes are involved; need to be more precise w.r.t. |
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[f474e91] | 427 | // where the ttype is to prevent errors |
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[7870799] | 428 | if ( |
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[f474e91] | 429 | ( params.size() != params2.size() || func->returns.size() != func2->returns.size() ) |
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| 430 | && ! func->isTtype() |
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| 431 | && ! func2->isTtype() |
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| 432 | ) return; |
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| 433 | |
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[251ce80] | 434 | if ( ! unifyTypeList( params, params2, tenv, need, have, open ) ) return; |
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[954c954] | 435 | if ( ! unifyTypeList( |
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[251ce80] | 436 | func->returns, func2->returns, tenv, need, have, open ) ) return; |
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[7870799] | 437 | |
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[f474e91] | 438 | markAssertions( have, need, func ); |
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| 439 | markAssertions( have, need, func2 ); |
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| 440 | |
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| 441 | result = true; |
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| 442 | } |
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[7870799] | 443 | |
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[f474e91] | 444 | private: |
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[90ce35aa] | 445 | // Returns: other, cast as XInstType |
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| 446 | // Assigns this->result: whether types are compatible (up to generic parameters) |
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| 447 | template< typename XInstType > |
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| 448 | const XInstType * handleRefType( const XInstType * inst, const ast::Type * other ) { |
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[f474e91] | 449 | // check that the other type is compatible and named the same |
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[90ce35aa] | 450 | auto otherInst = dynamic_cast< const XInstType * >( other ); |
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[24d6572] | 451 | if (otherInst && inst->name == otherInst->name) |
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| 452 | this->result = otherInst; |
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[f474e91] | 453 | return otherInst; |
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| 454 | } |
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| 455 | |
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| 456 | /// Creates a tuple type based on a list of TypeExpr |
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| 457 | template< typename Iter > |
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[7870799] | 458 | static const ast::Type * tupleFromExprs( |
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[f474e91] | 459 | const ast::TypeExpr * param, Iter & crnt, Iter end, ast::CV::Qualifiers qs |
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| 460 | ) { |
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| 461 | std::vector< ast::ptr< ast::Type > > types; |
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| 462 | do { |
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| 463 | types.emplace_back( param->type ); |
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| 464 | |
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| 465 | ++crnt; |
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| 466 | if ( crnt == end ) break; |
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| 467 | param = strict_dynamic_cast< const ast::TypeExpr * >( crnt->get() ); |
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| 468 | } while(true); |
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| 469 | |
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| 470 | return new ast::TupleType{ std::move(types), qs }; |
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| 471 | } |
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| 472 | |
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[90ce35aa] | 473 | template< typename XInstType > |
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| 474 | void handleGenericRefType( const XInstType * inst, const ast::Type * other ) { |
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[f474e91] | 475 | // check that other type is compatible and named the same |
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[90ce35aa] | 476 | const XInstType * otherInst = handleRefType( inst, other ); |
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| 477 | if ( ! this->result ) return; |
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[7870799] | 478 | |
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[f474e91] | 479 | // check that parameters of types unify, if any |
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| 480 | const std::vector< ast::ptr< ast::Expr > > & params = inst->params; |
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[90ce35aa] | 481 | const std::vector< ast::ptr< ast::Expr > > & params2 = otherInst->params; |
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[f474e91] | 482 | |
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| 483 | auto it = params.begin(); |
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| 484 | auto jt = params2.begin(); |
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| 485 | for ( ; it != params.end() && jt != params2.end(); ++it, ++jt ) { |
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| 486 | auto param = strict_dynamic_cast< const ast::TypeExpr * >( it->get() ); |
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| 487 | auto param2 = strict_dynamic_cast< const ast::TypeExpr * >( jt->get() ); |
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| 488 | |
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| 489 | ast::ptr< ast::Type > pty = param->type; |
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| 490 | ast::ptr< ast::Type > pty2 = param2->type; |
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| 491 | |
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| 492 | bool isTuple = Tuples::isTtype( pty ); |
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| 493 | bool isTuple2 = Tuples::isTtype( pty2 ); |
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| 494 | |
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| 495 | if ( isTuple && isTuple2 ) { |
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| 496 | ++it; ++jt; // skip ttype parameters before break |
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[0bd46fd] | 497 | } else if ( isTuple ) { |
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[f474e91] | 498 | // bundle remaining params into tuple |
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| 499 | pty2 = tupleFromExprs( param2, jt, params2.end(), pty->qualifiers ); |
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| 500 | ++it; // skip ttype parameter for break |
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| 501 | } else if ( isTuple2 ) { |
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| 502 | // bundle remaining params into tuple |
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| 503 | pty = tupleFromExprs( param, it, params.end(), pty2->qualifiers ); |
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| 504 | ++jt; // skip ttype parameter for break |
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| 505 | } |
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| 506 | |
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[7870799] | 507 | if ( ! unifyExact( |
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[251ce80] | 508 | pty, pty2, tenv, need, have, open, noWiden() ) ) { |
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[f474e91] | 509 | result = false; |
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| 510 | return; |
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| 511 | } |
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| 512 | |
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| 513 | // ttype parameter should be last |
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| 514 | if ( isTuple || isTuple2 ) break; |
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| 515 | } |
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| 516 | result = it == params.end() && jt == params2.end(); |
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| 517 | } |
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| 518 | |
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| 519 | public: |
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[ee574a2] | 520 | void postvisit( const ast::StructInstType * aggrType ) { |
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[f474e91] | 521 | handleGenericRefType( aggrType, type2 ); |
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| 522 | } |
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| 523 | |
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[ee574a2] | 524 | void postvisit( const ast::UnionInstType * aggrType ) { |
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[f474e91] | 525 | handleGenericRefType( aggrType, type2 ); |
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| 526 | } |
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| 527 | |
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[ee574a2] | 528 | void postvisit( const ast::EnumInstType * aggrType ) { |
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[f474e91] | 529 | handleRefType( aggrType, type2 ); |
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| 530 | } |
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| 531 | |
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[ee574a2] | 532 | void postvisit( const ast::TraitInstType * aggrType ) { |
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[f474e91] | 533 | handleRefType( aggrType, type2 ); |
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| 534 | } |
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| 535 | |
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[ee574a2] | 536 | void postvisit( const ast::TypeInstType * typeInst ) { |
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[46da46b] | 537 | // assert( open.find( *typeInst ) == open.end() ); |
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[24d6572] | 538 | auto otherInst = dynamic_cast< const ast::TypeInstType * >( type2 ); |
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[2908f08] | 539 | if ( otherInst && typeInst->name == otherInst->name ) { |
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[24d6572] | 540 | this->result = otherInst; |
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[2908f08] | 541 | } |
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[f474e91] | 542 | } |
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| 543 | |
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| 544 | private: |
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| 545 | /// Creates a tuple type based on a list of Type |
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[0bd46fd] | 546 | |
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[7870799] | 547 | static bool unifyList( |
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| 548 | const std::vector< ast::ptr< ast::Type > > & list1, |
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| 549 | const std::vector< ast::ptr< ast::Type > > & list2, ast::TypeEnvironment & env, |
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[251ce80] | 550 | ast::AssertionSet & need, ast::AssertionSet & have, const ast::OpenVarSet & open |
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[f474e91] | 551 | ) { |
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| 552 | auto crnt1 = list1.begin(); |
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| 553 | auto crnt2 = list2.begin(); |
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| 554 | while ( crnt1 != list1.end() && crnt2 != list2.end() ) { |
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| 555 | const ast::Type * t1 = *crnt1; |
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| 556 | const ast::Type * t2 = *crnt2; |
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| 557 | bool isTuple1 = Tuples::isTtype( t1 ); |
---|
| 558 | bool isTuple2 = Tuples::isTtype( t2 ); |
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| 559 | |
---|
| 560 | // assumes ttype must be last parameter |
---|
| 561 | if ( isTuple1 && ! isTuple2 ) { |
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| 562 | // combine entirety of list2, then unify |
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[7870799] | 563 | return unifyExact( |
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| 564 | t1, tupleFromTypes( list2 ), env, need, have, open, |
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[251ce80] | 565 | noWiden() ); |
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[f474e91] | 566 | } else if ( ! isTuple1 && isTuple2 ) { |
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| 567 | // combine entirety of list1, then unify |
---|
| 568 | return unifyExact( |
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[7870799] | 569 | tupleFromTypes( list1 ), t2, env, need, have, open, |
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[251ce80] | 570 | noWiden() ); |
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[f474e91] | 571 | } |
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| 572 | |
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[7870799] | 573 | if ( ! unifyExact( |
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[251ce80] | 574 | t1, t2, env, need, have, open, noWiden() ) |
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[f474e91] | 575 | ) return false; |
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| 576 | |
---|
| 577 | ++crnt1; ++crnt2; |
---|
| 578 | } |
---|
| 579 | |
---|
| 580 | if ( crnt1 != list1.end() ) { |
---|
| 581 | // try unifying empty tuple type with ttype |
---|
| 582 | const ast::Type * t1 = *crnt1; |
---|
| 583 | if ( ! Tuples::isTtype( t1 ) ) return false; |
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[7870799] | 584 | // xxx - this doesn't generate an empty tuple, contrary to comment; both ported |
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[f474e91] | 585 | // from Rob's code |
---|
[7870799] | 586 | return unifyExact( |
---|
| 587 | t1, tupleFromTypes( list2 ), env, need, have, open, |
---|
[251ce80] | 588 | noWiden() ); |
---|
[f474e91] | 589 | } else if ( crnt2 != list2.end() ) { |
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| 590 | // try unifying empty tuple with ttype |
---|
| 591 | const ast::Type * t2 = *crnt2; |
---|
| 592 | if ( ! Tuples::isTtype( t2 ) ) return false; |
---|
[7870799] | 593 | // xxx - this doesn't generate an empty tuple, contrary to comment; both ported |
---|
[f474e91] | 594 | // from Rob's code |
---|
| 595 | return unifyExact( |
---|
[7870799] | 596 | tupleFromTypes( list1 ), t2, env, need, have, open, |
---|
[251ce80] | 597 | noWiden() ); |
---|
[f474e91] | 598 | } |
---|
| 599 | |
---|
| 600 | return true; |
---|
| 601 | } |
---|
| 602 | |
---|
| 603 | public: |
---|
[ee574a2] | 604 | void postvisit( const ast::TupleType * tuple ) { |
---|
[f474e91] | 605 | auto tuple2 = dynamic_cast< const ast::TupleType * >( type2 ); |
---|
| 606 | if ( ! tuple2 ) return; |
---|
| 607 | |
---|
[0bd3faf] | 608 | ast::Pass<TtypeExpander> expander{ tenv }; |
---|
[ef9988b] | 609 | |
---|
[d3aa64f1] | 610 | const ast::Type * flat = tuple->accept( expander ); |
---|
| 611 | const ast::Type * flat2 = tuple2->accept( expander ); |
---|
[f474e91] | 612 | |
---|
| 613 | auto types = flatten( flat ); |
---|
| 614 | auto types2 = flatten( flat2 ); |
---|
| 615 | |
---|
[251ce80] | 616 | result = unifyList( types, types2, tenv, need, have, open ); |
---|
[f474e91] | 617 | } |
---|
| 618 | |
---|
[ee574a2] | 619 | void postvisit( const ast::VarArgsType * ) { |
---|
[f474e91] | 620 | result = dynamic_cast< const ast::VarArgsType * >( type2 ); |
---|
| 621 | } |
---|
| 622 | |
---|
[ee574a2] | 623 | void postvisit( const ast::ZeroType * ) { |
---|
[f474e91] | 624 | result = dynamic_cast< const ast::ZeroType * >( type2 ); |
---|
| 625 | } |
---|
| 626 | |
---|
[ee574a2] | 627 | void postvisit( const ast::OneType * ) { |
---|
[f474e91] | 628 | result = dynamic_cast< const ast::OneType * >( type2 ); |
---|
[7870799] | 629 | } |
---|
[f474e91] | 630 | }; |
---|
| 631 | |
---|
[0bd3faf] | 632 | // size_t Unify::traceId = Stats::Heap::new_stacktrace_id("Unify"); |
---|
| 633 | |
---|
[7870799] | 634 | bool unify( |
---|
| 635 | const ast::ptr<ast::Type> & type1, const ast::ptr<ast::Type> & type2, |
---|
| 636 | ast::TypeEnvironment & env, ast::AssertionSet & need, ast::AssertionSet & have, |
---|
[251ce80] | 637 | ast::OpenVarSet & open |
---|
[2773ab8] | 638 | ) { |
---|
| 639 | ast::ptr<ast::Type> common; |
---|
[251ce80] | 640 | return unify( type1, type2, env, need, have, open, common ); |
---|
[2773ab8] | 641 | } |
---|
| 642 | |
---|
[7870799] | 643 | bool unify( |
---|
| 644 | const ast::ptr<ast::Type> & type1, const ast::ptr<ast::Type> & type2, |
---|
| 645 | ast::TypeEnvironment & env, ast::AssertionSet & need, ast::AssertionSet & have, |
---|
[251ce80] | 646 | ast::OpenVarSet & open, ast::ptr<ast::Type> & common |
---|
[ee574a2] | 647 | ) { |
---|
| 648 | ast::OpenVarSet closed; |
---|
[46da46b] | 649 | // findOpenVars( type1, open, closed, need, have, FirstClosed ); |
---|
| 650 | findOpenVars( type2, open, closed, need, have, env, FirstOpen ); |
---|
[7870799] | 651 | return unifyInexact( |
---|
[251ce80] | 652 | type1, type2, env, need, have, open, WidenMode{ true, true }, common ); |
---|
[ee574a2] | 653 | } |
---|
| 654 | |
---|
[7870799] | 655 | bool unifyExact( |
---|
| 656 | const ast::Type * type1, const ast::Type * type2, ast::TypeEnvironment & env, |
---|
| 657 | ast::AssertionSet & need, ast::AssertionSet & have, const ast::OpenVarSet & open, |
---|
[251ce80] | 658 | WidenMode widen |
---|
[f474e91] | 659 | ) { |
---|
| 660 | if ( type1->qualifiers != type2->qualifiers ) return false; |
---|
| 661 | |
---|
| 662 | auto var1 = dynamic_cast< const ast::TypeInstType * >( type1 ); |
---|
| 663 | auto var2 = dynamic_cast< const ast::TypeInstType * >( type2 ); |
---|
[46da46b] | 664 | bool isopen1 = var1 && env.lookup(*var1); |
---|
| 665 | bool isopen2 = var2 && env.lookup(*var2); |
---|
[f474e91] | 666 | |
---|
[46da46b] | 667 | if ( isopen1 && isopen2 ) { |
---|
| 668 | if ( var1->base->kind != var2->base->kind ) return false; |
---|
| 669 | return env.bindVarToVar( |
---|
| 670 | var1, var2, ast::TypeData{ var1->base->kind, var1->base->sized||var2->base->sized }, need, have, |
---|
[24d6572] | 671 | open, widen ); |
---|
[46da46b] | 672 | } else if ( isopen1 ) { |
---|
[24d6572] | 673 | return env.bindVar( var1, type2, ast::TypeData{var1->base}, need, have, open, widen ); |
---|
[46da46b] | 674 | } else if ( isopen2 ) { |
---|
[24d6572] | 675 | return env.bindVar( var2, type1, ast::TypeData{var2->base}, need, have, open, widen ); |
---|
[8f31be6] | 676 | } else { |
---|
[0bd3faf] | 677 | return ast::Pass<Unify>::read( |
---|
[251ce80] | 678 | type1, type2, env, need, have, open, widen ); |
---|
[f474e91] | 679 | } |
---|
| 680 | } |
---|
| 681 | |
---|
[7870799] | 682 | bool unifyInexact( |
---|
| 683 | const ast::ptr<ast::Type> & type1, const ast::ptr<ast::Type> & type2, |
---|
| 684 | ast::TypeEnvironment & env, ast::AssertionSet & need, ast::AssertionSet & have, |
---|
[251ce80] | 685 | const ast::OpenVarSet & open, WidenMode widen, |
---|
[7870799] | 686 | ast::ptr<ast::Type> & common |
---|
[f474e91] | 687 | ) { |
---|
| 688 | ast::CV::Qualifiers q1 = type1->qualifiers, q2 = type2->qualifiers; |
---|
[7870799] | 689 | |
---|
| 690 | // force t1 and t2 to be cloned if their qualifiers must be stripped, so that type1 and |
---|
[f474e91] | 691 | // type2 are left unchanged; calling convention forces type{1,2}->strong_ref >= 1 |
---|
[2890212] | 692 | ast::Type * t1 = shallowCopy(type1.get()); |
---|
| 693 | ast::Type * t2 = shallowCopy(type2.get()); |
---|
| 694 | t1->qualifiers = {}; |
---|
| 695 | t2->qualifiers = {}; |
---|
[f49b3fc] | 696 | ast::ptr< ast::Type > t1_(t1); |
---|
| 697 | ast::ptr< ast::Type > t2_(t2); |
---|
[7870799] | 698 | |
---|
[251ce80] | 699 | if ( unifyExact( t1, t2, env, need, have, open, widen ) ) { |
---|
[f474e91] | 700 | // if exact unification on unqualified types, try to merge qualifiers |
---|
| 701 | if ( q1 == q2 || ( ( q1 > q2 || widen.first ) && ( q2 > q1 || widen.second ) ) ) { |
---|
[2890212] | 702 | t1->qualifiers = q1 | q2; |
---|
| 703 | common = t1; |
---|
[f474e91] | 704 | return true; |
---|
| 705 | } else { |
---|
| 706 | return false; |
---|
| 707 | } |
---|
| 708 | |
---|
[251ce80] | 709 | } else if (( common = commonType( t1, t2, env, need, have, open, widen ))) { |
---|
[f474e91] | 710 | // no exact unification, but common type |
---|
[2890212] | 711 | auto c = shallowCopy(common.get()); |
---|
| 712 | c->qualifiers = q1 | q2; |
---|
| 713 | common = c; |
---|
[f474e91] | 714 | return true; |
---|
| 715 | } else { |
---|
| 716 | return false; |
---|
| 717 | } |
---|
| 718 | } |
---|
| 719 | |
---|
[54e41b3] | 720 | ast::ptr<ast::Type> extractResultType( const ast::FunctionType * func ) { |
---|
[4139e3d] | 721 | if ( func->returns.empty() ) return new ast::VoidType{}; |
---|
[954c954] | 722 | if ( func->returns.size() == 1 ) return func->returns[0]; |
---|
[4139e3d] | 723 | |
---|
| 724 | std::vector<ast::ptr<ast::Type>> tys; |
---|
[954c954] | 725 | for ( const auto & decl : func->returns ) { |
---|
| 726 | tys.emplace_back( decl ); |
---|
[4139e3d] | 727 | } |
---|
| 728 | return new ast::TupleType{ std::move(tys) }; |
---|
[54e41b3] | 729 | } |
---|
[51b7345] | 730 | } // namespace ResolvExpr |
---|
[a32b204] | 731 | |
---|
| 732 | // Local Variables: // |
---|
| 733 | // tab-width: 4 // |
---|
| 734 | // mode: c++ // |
---|
| 735 | // compile-command: "make install" // |
---|
| 736 | // End: // |
---|