1 
2 // Copyright (C) 2009-2012 Lorenzo Caminiti
3 // Distributed under the Boost Software License, Version 1.0
4 // (see accompanying file LICENSE_1_0.txt or a copy at
5 // http://www.boost.org/LICENSE_1_0.txt)
6 // Home at http://www.boost.org/libs/local_function
7 
8 #ifndef BOOST_LOCAL_FUNCTION_AUX_NAME_HPP_
9 #define BOOST_LOCAL_FUNCTION_AUX_NAME_HPP_
10 
11 #include <boost/local_function/config.hpp>
12 #include <boost/local_function/aux_/macro/decl.hpp>
13 #include <boost/local_function/aux_/macro/code_/functor.hpp>
14 #include <boost/local_function/detail/preprocessor/keyword/recursive.hpp>
15 #include <boost/local_function/detail/preprocessor/keyword/inline.hpp>
16 #include <boost/local_function/aux_/function.hpp>
17 #include <boost/local_function/aux_/symbol.hpp>
18 #include <boost/preprocessor/control/iif.hpp>
19 #include <boost/preprocessor/control/expr_iif.hpp>
20 #include <boost/preprocessor/logical/bitor.hpp>
21 #include <boost/preprocessor/tuple/eat.hpp>
22 
23 // PRIVATE //
24 
25 #define BOOST_LOCAL_FUNCTION_AUX_NAME_LOCAL_TYPE_(local_function_name) \
26     BOOST_LOCAL_FUNCTION_AUX_SYMBOL( (local_type)(local_function_name) )
27 
28 #define BOOST_LOCAL_FUNCTION_AUX_NAME_INIT_RECURSION_FUNC_ \
29     BOOST_LOCAL_FUNCTION_AUX_SYMBOL( (init_recursion) )
30 
31 #define BOOST_LOCAL_FUNCTION_AUX_NAME_RECURSIVE_FUNC_( \
32         is_recursive, local_function_name) \
33     BOOST_PP_IIF(is_recursive, \
34         local_function_name \
35     , \
36         BOOST_LOCAL_FUNCTION_AUX_SYMBOL( (nonrecursive_local_function_name) ) \
37     )
38 
39 #define BOOST_LOCAL_FUNCTION_AUX_NAME_END_LOCAL_FUNCTOR_(typename01, \
40         local_function_name, is_recursive, \
41         local_functor_name, nonlocal_functor_name) \
42     /* FUNCTION macro expanded to: typedef class functor ## __LINE__ { ... */ \
43     BOOST_PP_EXPR_IIF(is_recursive, \
44         /* member var with function name for recursive calls; it cannot be */ \
45         /* `const` because it is init after construction (because */ \
46         /* constructor doesn't know local function name) */ \
47         /* run-time: even when optimizing, recursive calls cannot be */ \
48         /* optimized (i.e., they must be via the non-local functor) */ \
49         /* because this cannot be a mem ref because its name is not known */ \
50         /* by the constructor so it cannot be set by the mem init list */ \
51     private: \
52         BOOST_LOCAL_FUNCTION_AUX_CODE_FUNCTOR_TYPE \
53                 BOOST_LOCAL_FUNCTION_AUX_NAME_RECURSIVE_FUNC_(is_recursive, \
54                         local_function_name); \
55         /* run-time: the `init_recursion()` function cannot be called */ \
56         /* by the constructor to allow for compiler optimization */ \
57         /* (inlining) so it must be public to be called (see below) */ \
58     public: \
59         inline void BOOST_LOCAL_FUNCTION_AUX_NAME_INIT_RECURSION_FUNC_( \
60                 BOOST_LOCAL_FUNCTION_AUX_CODE_FUNCTOR_TYPE& functor) { \
61             local_function_name = functor; \
62         } \
63     ) \
64     } BOOST_LOCAL_FUNCTION_AUX_NAME_LOCAL_TYPE_(local_function_name); \
65     /* local functor can be passed as tparam only on C++11 (faster) */ \
66     BOOST_LOCAL_FUNCTION_AUX_NAME_LOCAL_TYPE_(local_function_name) \
67             local_functor_name(BOOST_LOCAL_FUNCTION_AUX_DECL_ARGS_VAR.value); \
68     /* non-local functor can always be passed as tparam (but slower) */ \
69     BOOST_PP_EXPR_IIF(typename01, typename) \
70     BOOST_LOCAL_FUNCTION_AUX_NAME_LOCAL_TYPE_(local_function_name):: \
71             BOOST_LOCAL_FUNCTION_AUX_CODE_FUNCTOR_TYPE \
72             nonlocal_functor_name; /* functor variable */ \
73     /* the order of the following 2 function calls cannot be changed */ \
74     /* because init_recursion uses the local_functor so the local_functor */ \
75     /* must be init first */ \
76     local_functor_name.BOOST_LOCAL_FUNCTION_AUX_FUNCTION_INIT_CALL_FUNC( \
77             &local_functor_name, nonlocal_functor_name); \
78     BOOST_PP_EXPR_IIF(is_recursive, \
79         /* init recursion causes MSVC to not optimize local function not */ \
80         /* even when local functor is used as template parameter so no */ \
81         /* recursion unless all inlining optimizations are specified off */ \
82         local_functor_name.BOOST_LOCAL_FUNCTION_AUX_NAME_INIT_RECURSION_FUNC_( \
83                 nonlocal_functor_name); \
84     )
85 
86 #define BOOST_LOCAL_FUNCTION_AUX_NAME_FUNCTOR_(local_function_name) \
87     BOOST_LOCAL_FUNCTION_AUX_SYMBOL( (local_function_name) )
88 
89 // This can always be passed as a template parameters (on all compilers).
90 // However, it is slower because it cannot be inlined.
91 // Passed at tparam: Yes (on all C++). Inlineable: No. Recursive: No.
92 #define BOOST_LOCAL_FUNCTION_AUX_NAME_(typename01, local_function_name) \
93     BOOST_LOCAL_FUNCTION_AUX_NAME_END_LOCAL_FUNCTOR_(typename01, \
94             local_function_name, \
95             /* local function is not recursive (because recursion and its */ \
96             /* initialization cannot be inlined even on C++11, */ \
97             /* so this allows optimization at least on C++11) */ \
98             0 /* not recursive */ , \
99             /* local functor */ \
100             BOOST_LOCAL_FUNCTION_AUX_NAME_FUNCTOR_(local_function_name), \
101             /* local function declared as non-local functor -- but it can */ \
102             /* be inlined only by C++11 and it cannot be recursive */ \
103             local_function_name)
104 
105 // This is faster on some compilers but not all (e.g., it is faster on GCC
106 // because its optimization inlines it but not on MSVC). However, it cannot be
107 // passed as a template parameter on non C++11 compilers.
108 // Passed at tparam: Only on C++11. Inlineable: Yes. Recursive: No.
109 #define BOOST_LOCAL_FUNCTION_AUX_NAME_INLINE_(typename01, local_function_name) \
110     BOOST_LOCAL_FUNCTION_AUX_NAME_END_LOCAL_FUNCTOR_(typename01, \
111             local_function_name, \
112             /* inlined local function is never recursive (because recursion */ \
113             /* and its initialization cannot be inlined)*/ \
114             0 /* not recursive */ , \
115             /* inlined local function declared as local functor (maybe */ \
116             /* inlined even by non C++11 -- but it can be passed as */ \
117             /* template parameter only on C++11 */ \
118             local_function_name, \
119             /* non-local functor */ \
120             BOOST_LOCAL_FUNCTION_AUX_NAME_FUNCTOR_(local_function_name))
121 
122 // This is slower on all compilers (C++11 and non) because recursion and its
123 // initialization can never be inlined.
124 // Passed at tparam: Yes. Inlineable: No. Recursive: Yes.
125 #define BOOST_LOCAL_FUNCTION_AUX_NAME_RECURSIVE_( \
126         typename01, local_function_name) \
127     BOOST_LOCAL_FUNCTION_AUX_NAME_END_LOCAL_FUNCTOR_(typename01, \
128             local_function_name, \
129             /* recursive local function -- but it cannot be inlined */ \
130             1 /* recursive */ , \
131             /* local functor */ \
132             BOOST_LOCAL_FUNCTION_AUX_NAME_FUNCTOR_(local_function_name), \
133             /* local function declared as non-local functor -- but it can */ \
134             /* be inlined only by C++11 */ \
135             local_function_name)
136 
137 // Inlined local functions are specified by `..._NAME(inline name)`.
138 // They have more chances to be inlined for faster run-times by some compilers
139 // (for example by GCC but not by MSVC). C++11 compilers can always inline
140 // local functions even if they are not explicitly specified inline.
141 #define BOOST_LOCAL_FUNCTION_AUX_NAME_PARSE_INLINE_( \
142         typename01, qualified_name) \
143     BOOST_PP_IIF(BOOST_PP_BITOR( \
144             BOOST_LOCAL_FUNCTION_CONFIG_LOCALS_AS_TPARAMS, \
145             BOOST_LOCAL_FUNCTION_DETAIL_PP_KEYWORD_IS_INLINE_FRONT( \
146                     qualified_name)), \
147         /* on C++11 always use inlining because compilers might optimize */ \
148         /* it to be faster and it can also be passed as tparam */ \
149         BOOST_LOCAL_FUNCTION_AUX_NAME_INLINE_ \
150     , \
151         /* on non C++11 don't use liniling unless explicitly specified by */ \
152         /* programmers `inline name` the inlined local function cannot be */ \
153         /* passed as tparam */ \
154         BOOST_LOCAL_FUNCTION_AUX_NAME_ \
155     )(typename01, BOOST_LOCAL_FUNCTION_DETAIL_PP_KEYWORD_INLINE_REMOVE_FRONT( \
156             qualified_name))
157 
158 // Expand to 1 iff `recursive name` or `recursive inline name` or
159 // `inline recursive name`.
160 #define BOOST_LOCAL_FUNCTION_AUX_NAME_IS_RECURSIVE_(qualified_name) \
161     BOOST_LOCAL_FUNCTION_DETAIL_PP_KEYWORD_IS_RECURSIVE_FRONT( \
162     BOOST_LOCAL_FUNCTION_DETAIL_PP_KEYWORD_INLINE_REMOVE_FRONT( \
163         qualified_name \
164     ))
165 
166 // Revmoes `recursive`, `inline recursive`, and `recursive inline` from front.
167 #define BOOST_LOCAL_FUNCTION_AUX_NAME_REMOVE_RECURSIVE_AND_INLINE_( \
168         qualified_name) \
169     BOOST_LOCAL_FUNCTION_DETAIL_PP_KEYWORD_RECURSIVE_REMOVE_FRONT( \
170     BOOST_LOCAL_FUNCTION_DETAIL_PP_KEYWORD_INLINE_REMOVE_FRONT( \
171     BOOST_LOCAL_FUNCTION_DETAIL_PP_KEYWORD_RECURSIVE_REMOVE_FRONT( \
172         qualified_name \
173     )))
174 
175 #define BOOST_LOCAL_FUNCTION_AUX_NAME_RECURSIVE_REMOVE_(qualified_name) \
176     BOOST_PP_IIF(BOOST_LOCAL_FUNCTION_AUX_NAME_IS_RECURSIVE_(qualified_name), \
177         BOOST_LOCAL_FUNCTION_AUX_NAME_REMOVE_RECURSIVE_AND_INLINE_ \
178     , \
179         qualified_name /* might be `name` or `inline name` */ \
180         BOOST_PP_TUPLE_EAT(1) \
181     )(qualified_name)
182 
183 // Recursive local function are specified by `..._NAME(recursive name)`.
184 // They can never be inlined for faster run-time (not even by C++11 compilers).
185 #define BOOST_LOCAL_FUNCTION_AUX_NAME_PARSE_RECURSIVE_( \
186         typename01, qualified_name) \
187     BOOST_PP_IIF(BOOST_LOCAL_FUNCTION_AUX_NAME_IS_RECURSIVE_(qualified_name), \
188         /* recursion can never be inlined (not even on C++11) */ \
189         BOOST_LOCAL_FUNCTION_AUX_NAME_RECURSIVE_ \
190     , \
191         BOOST_LOCAL_FUNCTION_AUX_NAME_PARSE_INLINE_ \
192     )(typename01, \
193             BOOST_LOCAL_FUNCTION_AUX_NAME_RECURSIVE_REMOVE_(qualified_name))
194 
195 // PUBLIC //
196 
197 #define BOOST_LOCAL_FUNCTION_AUX_NAME(typename01, qualified_name) \
198     BOOST_LOCAL_FUNCTION_AUX_NAME_PARSE_RECURSIVE_(typename01, qualified_name)
199 
200 #endif // #include guard
201 
202