source: src/AST/Pass.proto.hpp@ bf22bc6

ADT arm-eh ast-experimental enum forall-pointer-decay jacob/cs343-translation jenkins-sandbox new-ast new-ast-unique-expr pthread-emulation qualifiedEnum
Last change on this file since bf22bc6 was 0e42794, checked in by Aaron Moss <a3moss@…>, 6 years ago

Rewrite WithSymbolTable pass accessory to use ast::SymbolTable
  • Property mode set to 100644
File size: 12.6 KB
Line 
1//
2// Cforall Version 1.0.0 Copyright (C) 2019 University of Waterloo
3//
4// The contents of this file are covered under the licence agreement in the
5// file "LICENCE" distributed with Cforall.
6//
7// Pass.impl.hpp --
8//
9// Author : Thierry Delisle
10// Created On : Thu May 09 15::37::05 2019
11// Last Modified By :
12// Last Modified On :
13// Update Count :
14//
15
16#pragma once
17// IWYU pragma: private, include "Pass.hpp"
18
19namespace ast {
20template<typename pass_type>
21class Pass;
22
23namespace __pass {
24 typedef std::function<void( void * )> cleanup_func_t;
25 typedef std::function<void( cleanup_func_t, void * )> at_cleanup_t;
26
27
28 // boolean reference that may be null
29 // either refers to a boolean value or is null and returns true
30 class bool_ref {
31 public:
32 bool_ref() = default;
33 ~bool_ref() = default;
34
35 operator bool() { return m_ref ? *m_ref : true; }
36 bool operator=( bool val ) { assert(m_ref); return *m_ref = val; }
37
38 private:
39
40 friend class visit_children_guard;
41
42 bool * set( bool * val ) {
43 bool * prev = m_ref;
44 m_ref = val;
45 return prev;
46 }
47
48 bool * m_ref = nullptr;
49 };
50
51 // Implementation of the guard value
52 // Created inside the visit scope
53 class guard_value {
54 public:
55 /// Push onto the cleanup
56 guard_value( at_cleanup_t * at_cleanup ) {
57 if( at_cleanup ) {
58 *at_cleanup = [this]( cleanup_func_t && func, void* val ) {
59 push( std::move( func ), val );
60 };
61 }
62 }
63
64 ~guard_value() {
65 while( !cleanups.empty() ) {
66 auto& cleanup = cleanups.top();
67 cleanup.func( cleanup.val );
68 cleanups.pop();
69 }
70 }
71
72 void push( cleanup_func_t && func, void* val ) {
73 cleanups.emplace( std::move(func), val );
74 }
75
76 private:
77 struct cleanup_t {
78 cleanup_func_t func;
79 void * val;
80
81 cleanup_t( cleanup_func_t&& func, void * val ) : func(func), val(val) {}
82 };
83
84 std::stack< cleanup_t > cleanups;
85 };
86
87 // Guard structure implementation for whether or not children should be visited
88 class visit_children_guard {
89 public:
90
91 visit_children_guard( bool_ref * ref )
92 : m_val ( true )
93 , m_prev( ref ? ref->set( &m_val ) : nullptr )
94 , m_ref ( ref )
95 {}
96
97 ~visit_children_guard() {
98 if( m_ref ) {
99 m_ref->set( m_prev );
100 }
101 }
102
103 operator bool() { return m_val; }
104
105 private:
106 bool m_val;
107 bool * m_prev;
108 bool_ref * m_ref;
109 };
110
111 /// "Short hand" to check if this is a valid previsit function
112 /// Mostly used to make the static_assert look (and print) prettier
113 template<typename pass_t, typename node_t>
114 struct is_valid_previsit {
115 using ret_t = decltype( ((pass_t*)nullptr)->previsit( (const node_t *)nullptr ) );
116
117 static constexpr bool value = std::is_void< ret_t >::value ||
118 std::is_base_of<const node_t, typename std::remove_pointer<ret_t>::type >::value;
119 };
120
121 /// Used by previsit implementation
122 /// We need to reassign the result to 'node', unless the function
123 /// returns void, then we just leave 'node' unchanged
124 template<bool is_void>
125 struct __assign;
126
127 template<>
128 struct __assign<true> {
129 template<typename pass_t, typename node_t>
130 static inline void result( pass_t & pass, const node_t * & node ) {
131 pass.previsit( node );
132 }
133 };
134
135 template<>
136 struct __assign<false> {
137 template<typename pass_t, typename node_t>
138 static inline void result( pass_t & pass, const node_t * & node ) {
139 node = pass.previsit( node );
140 assertf(node, "Previsit must not return NULL");
141 }
142 };
143
144 /// Used by postvisit implementation
145 /// We need to return the result unless the function
146 /// returns void, then we just return the original node
147 template<bool is_void>
148 struct __return;
149
150 template<>
151 struct __return<true> {
152 template<typename pass_t, typename node_t>
153 static inline const node_t * result( pass_t & pass, const node_t * & node ) {
154 pass.postvisit( node );
155 return node;
156 }
157 };
158
159 template<>
160 struct __return<false> {
161 template<typename pass_t, typename node_t>
162 static inline auto result( pass_t & pass, const node_t * & node ) {
163 return pass.postvisit( node );
164 }
165 };
166
167 //-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
168 // Deep magic (a.k.a template meta programming) to make the templated visitor work
169 // Basically the goal is to make 2 previsit
170 // 1 - Use when a pass implements a valid previsit. This uses overloading which means the any overload of
171 // 'pass.previsit( node )' that compiles will be used for that node for that type
172 // This requires that this option only compile for passes that actually define an appropriate visit.
173 // SFINAE will make sure the compilation errors in this function don't halt the build.
174 // See http://en.cppreference.com/w/cpp/language/sfinae for details on SFINAE
175 // 2 - Since the first implementation might not be specilizable, the second implementation exists and does nothing.
176 // This is needed only to eliminate the need for passes to specify any kind of handlers.
177 // The second implementation only works because it has a lower priority. This is due to the bogus last parameter.
178 // The second implementation takes a long while the first takes an int. Since the caller always passes an literal 0
179 // the first implementation takes priority in regards to overloading.
180 //-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
181 // PreVisit : may mutate the pointer passed in if the node is mutated in the previsit call
182 template<typename pass_t, typename node_t>
183 static inline auto previsit( pass_t & pass, const node_t * & node, int ) -> decltype( pass.previsit( node ), void() ) {
184 static_assert(
185 is_valid_previsit<pass_t, node_t>::value,
186 "Previsit may not change the type of the node. It must return its paremeter or void."
187 );
188
189 __assign<
190 std::is_void<
191 decltype( pass.previsit( node ) )
192 >::value
193 >::result( pass, node );
194 }
195
196 template<typename pass_t, typename node_t>
197 static inline auto previsit( pass_t &, const node_t *, long ) {}
198
199 // PostVisit : never mutates the passed pointer but may return a different node
200 template<typename pass_t, typename node_t>
201 static inline auto postvisit( pass_t & pass, const node_t * node, int ) ->
202 decltype( pass.postvisit( node ), node->accept( *(Visitor*)nullptr ) )
203 {
204 return __return<
205 std::is_void<
206 decltype( pass.postvisit( node ) )
207 >::value
208 >::result( pass, node );
209 }
210
211 template<typename pass_t, typename node_t>
212 static inline const node_t * postvisit( pass_t &, const node_t * node, long ) { return node; }
213
214 //-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
215 // Deep magic (a.k.a template meta programming) continued
216 // To make the templated visitor be more expressive, we allow 'accessories' : classes/structs the implementation can inherit
217 // from in order to get extra functionallity for example
218 // class ErrorChecker : WithShortCircuiting { ... };
219 // Pass<ErrorChecker> checker;
220 // this would define a pass that uses the templated visitor with the additionnal feature that it has short circuiting
221 // Note that in all cases the accessories are not required but guarantee the requirements of the feature is matched
222 //-------------------------------------------------------------------------------------------------------------------------------------------------------------------------
223 // For several accessories, the feature is enabled by detecting that a specific field is present
224 // Use a macro the encapsulate the logic of detecting a particular field
225 // The type is not strictly enforced but does match the accessory
226 #define FIELD_PTR( name, default_type ) \
227 template< typename pass_t > \
228 static inline auto name( pass_t & pass, int ) -> decltype( &pass.name ) { return &pass.name; } \
229 \
230 template< typename pass_t > \
231 static inline default_type * name( pass_t &, long ) { return nullptr; }
232
233 // List of fields and their expected types
234 FIELD_PTR( env, const ast::TypeSubstitution * )
235 FIELD_PTR( stmtsToAddBefore, std::list< ast::ptr< ast::Stmt > > )
236 FIELD_PTR( stmtsToAddAfter , std::list< ast::ptr< ast::Stmt > > )
237 FIELD_PTR( declsToAddBefore, std::list< ast::ptr< ast::Decl > > )
238 FIELD_PTR( declsToAddAfter , std::list< ast::ptr< ast::Decl > > )
239 FIELD_PTR( visit_children, __pass::bool_ref )
240 FIELD_PTR( at_cleanup, __pass::at_cleanup_t )
241 FIELD_PTR( visitor, ast::Pass<pass_t> * const )
242
243 // Remove the macro to make sure we don't clash
244 #undef FIELD_PTR
245
246 // Another feature of the templated visitor is that it calls beginScope()/endScope() for compound statement.
247 // All passes which have such functions are assumed desire this behaviour
248 // detect it using the same strategy
249 namespace scope {
250 template<typename pass_t>
251 static inline auto enter( pass_t & pass, int ) -> decltype( pass.beginScope(), void() ) {
252 pass.beginScope();
253 }
254
255 template<typename pass_t>
256 static inline void enter( pass_t &, long ) {}
257
258 template<typename pass_t>
259 static inline auto leave( pass_t & pass, int ) -> decltype( pass.endScope(), void() ) {
260 pass.endScope();
261 }
262
263 template<typename pass_t>
264 static inline void leave( pass_t &, long ) {}
265 };
266
267 // Finally certain pass desire an up to date symbol table automatically
268 // detect the presence of a member name `symtab` and call all the members appropriately
269 namespace symtab {
270 // Some simple scoping rules
271 template<typename pass_t>
272 static inline auto enter( pass_t & pass, int ) -> decltype( pass.symtab.enterScope(), void() ) {
273 pass.symtab.enterScope();
274 }
275
276 template<typename pass_t>
277 static inline auto enter( pass_t &, long ) {}
278
279 template<typename pass_t>
280 static inline auto leave( pass_t & pass, int ) -> decltype( pass.symtab.leaveScope(), void() ) {
281 pass.symtab.leaveScope();
282 }
283
284 template<typename pass_t>
285 static inline auto leave( pass_t &, long ) {}
286
287 // The symbol table has 2 kind of functions mostly, 1 argument and 2 arguments
288 // Create macro to condense these common patterns
289 #define SYMTAB_FUNC1( func, type ) \
290 template<typename pass_t> \
291 static inline auto func( pass_t & pass, int, type arg ) -> decltype( pass.symtab.func( arg ), void() ) {\
292 pass.symtab.func( arg ); \
293 } \
294 \
295 template<typename pass_t> \
296 static inline void func( pass_t &, long, type ) {}
297
298 #define SYMTAB_FUNC2( func, type1, type2 ) \
299 template<typename pass_t> \
300 static inline auto func( pass_t & pass, int, type1 arg1, type2 arg2 ) -> decltype( pass.symtab.func( arg1, arg2 ), void () ) {\
301 pass.symtab.func( arg1, arg2 ); \
302 } \
303 \
304 template<typename pass_t> \
305 static inline void func( pass_t &, long, type1, type2 ) {}
306
307 SYMTAB_FUNC1( addId , const DeclWithType * );
308 SYMTAB_FUNC1( addType , const NamedTypeDecl * );
309 SYMTAB_FUNC1( addStruct , const StructDecl * );
310 SYMTAB_FUNC1( addEnum , const EnumDecl * );
311 SYMTAB_FUNC1( addUnion , const UnionDecl * );
312 SYMTAB_FUNC1( addTrait , const TraitDecl * );
313 SYMTAB_FUNC2( addWith , const std::vector< ptr<Expr> > &, const Node * );
314
315 // A few extra functions have more complicated behaviour, they are hand written
316 template<typename pass_t>
317 static inline auto addStructFwd( pass_t & pass, int, const ast::StructDecl * decl ) -> decltype( pass.symtab.addStruct( decl ), void() ) {
318 ast::StructDecl * fwd = new ast::StructDecl( decl->location, decl->name );
319 fwd->params = decl->params;
320 pass.symtab.addStruct( fwd );
321 }
322
323 template<typename pass_t>
324 static inline void addStructFwd( pass_t &, long, const ast::StructDecl * ) {}
325
326 template<typename pass_t>
327 static inline auto addUnionFwd( pass_t & pass, int, const ast::UnionDecl * decl ) -> decltype( pass.symtab.addUnion( decl ), void() ) {
328 UnionDecl * fwd = new UnionDecl( decl->location, decl->name );
329 fwd->params = decl->params;
330 pass.symtab.addUnion( fwd );
331 }
332
333 template<typename pass_t>
334 static inline void addUnionFwd( pass_t &, long, const ast::UnionDecl * ) {}
335
336 template<typename pass_t>
337 static inline auto addStruct( pass_t & pass, int, const std::string & str ) -> decltype( pass.symtab.addStruct( str ), void() ) {
338 if ( ! pass.symtab.lookupStruct( str ) ) {
339 pass.symtab.addStruct( str );
340 }
341 }
342
343 template<typename pass_t>
344 static inline void addStruct( pass_t &, long, const std::string & ) {}
345
346 template<typename pass_t>
347 static inline auto addUnion( pass_t & pass, int, const std::string & str ) -> decltype( pass.symtab.addUnion( str ), void() ) {
348 if ( ! pass.symtab.lookupUnion( str ) ) {
349 pass.symtab.addUnion( str );
350 }
351 }
352
353 template<typename pass_t>
354 static inline void addUnion( pass_t &, long, const std::string & ) {}
355
356 #undef SYMTAB_FUNC1
357 #undef SYMTAB_FUNC2
358 };
359};
360};
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