1 /**
2  * Compiler implementation of the
3  * $(LINK2 http://www.dlang.org, D programming language).
4  *
5  * Copyright:   Copyright (C) 1985-1998 by Symantec
6  *              Copyright (C) 1999-2021 by The D Language Foundation, All Rights Reserved
7  * Authors:     $(LINK2 http://www.digitalmars.com, Walter Bright)
8  * License:     $(LINK2 http://www.boost.org/LICENSE_1_0.txt, Boost License 1.0)
9  * Source:      $(LINK2 https://github.com/dlang/dmd/blob/master/src/dmd/backend/type.d, backend/_type.d)
10  */
11 
12 module dmd.backend.type;
13 
14 // Online documentation: https://dlang.org/phobos/dmd_backend_type.html
15 
16 import dmd.backend.cdef;
17 import dmd.backend.cc : block, Blockx, Classsym, Symbol, param_t;
18 import dmd.backend.code;
19 import dmd.backend.dlist;
20 import dmd.backend.el : elem;
21 import dmd.backend.ty;
22 
23 extern (C++):
24 @nogc:
25 nothrow:
26 
27 // type.h
28 
29 alias mangle_t = ubyte;
30 enum
31 {
32     mTYman_c      = 1,      // C mangling
33     mTYman_cpp    = 2,      // C++ mangling
34     mTYman_pas    = 3,      // Pascal mangling
35     mTYman_for    = 4,      // FORTRAN mangling
36     mTYman_sys    = 5,      // _syscall mangling
37     mTYman_std    = 6,      // _stdcall mangling
38     mTYman_d      = 7,      // D mangling
39 }
40 
41 /// Values for Tflags:
42 alias type_flags_t = ushort;
43 enum
44 {
45     TFprototype   = 1,      // if this function is prototyped
46     TFfixed       = 2,      // if prototype has a fixed # of parameters
47     TFgenerated   = 4,      // C: if we generated the prototype ourselves
48     TFdependent   = 4,      // CPP: template dependent type
49     TFforward     = 8,      // TYstruct: if forward reference of tag name
50     TFsizeunknown = 0x10,   // TYstruct,TYarray: if size of type is unknown
51                             // TYmptr: the Stag is TYident type
52     TFfuncret     = 0x20,   // C++,tyfunc(): overload based on function return value
53     TFfuncparam   = 0x20,   // TYarray: top level function parameter
54     TFhydrated    = 0x20,   // type data already hydrated
55     TFstatic      = 0x40,   // TYarray: static dimension
56     TFvla         = 0x80,   // TYarray: variable length array
57     TFemptyexc    = 0x100,  // tyfunc(): empty exception specification
58 }
59 
60 alias type = TYPE;
61 
62 void type_incCount(type* t);
63 void type_setIdent(type* t, char* ident);
64 
65 void symbol_struct_addField(Symbol* s, const(char)* name, type* t, uint offset);
66 
67 // Return true if type is a struct, class or union
68 bool type_struct(const type* t) { return tybasic(t.Tty) == TYstruct; }
69 
70 struct TYPE
71 {
72     debug ushort id;
73     enum IDtype = 0x1234;
74 
75     tym_t Tty;     /* mask (TYxxx)                         */
76     type_flags_t Tflags; // TFxxxxx
77 
78     mangle_t Tmangle; // name mangling
79 
80     uint Tcount; // # pointing to this type
81     char* Tident; // TYident: identifier; TYdarray, TYaarray: pretty name for debug info
82     TYPE* Tnext; // next in list
83                                 // TYenum: gives base type
84     union
85     {
86         targ_size_t Tdim;   // TYarray: # of elements in array
87         elem* Tel;          // TFvla: gives dimension (NULL if '*')
88         param_t* Tparamtypes; // TYfunc, TYtemplate: types of function parameters
89         Classsym* Ttag;     // TYstruct,TYmemptr: tag symbol
90                             // TYenum,TYvtshape: tag symbol
91         type* Talternate;   // C++: typtr: type of parameter before converting
92         type* Tkey;         // typtr: key type for associative arrays
93     }
94 
95     list_t Texcspec;        // tyfunc(): list of types of exception specification
96     Symbol *Ttypedef;       // if this type came from a typedef, this is
97                             // the typedef symbol
98 }
99 
100 struct typetemp_t
101 {
102     TYPE Ttype;
103 
104     /* Tsym should really be part of a derived class, as we only
105         allocate room for it if TYtemplate
106      */
107     Symbol *Tsym;               // primary class template symbol
108 }
109 
110 void type_debug(const type* t)
111 {
112     debug assert(t.id == t.IDtype);
113 }
114 
115 // Return name mangling of type
116 mangle_t type_mangle(const type *t) { return t.Tmangle; }
117 
118 // Return true if function type has a variable number of arguments
119 bool variadic(const type *t) { return (t.Tflags & (TFprototype | TFfixed)) == TFprototype; }
120 
121 extern __gshared type*[TYMAX] tstypes;
122 extern __gshared type*[TYMAX] tsptr2types;
123 
124 extern __gshared
125 {
126     type* tslogical;
127     type* chartype;
128     type* tsclib;
129     type* tsdlib;
130     type* tspvoid;
131     type* tspcvoid;
132     type* tsptrdiff;
133     type* tssize;
134     type* tstrace;
135 }
136 
137 /* Functions    */
138 void type_print(const type* t);
139 void type_free(type *);
140 void type_init();
141 void type_term();
142 type *type_copy(type *);
143 elem *type_vla_fix(type **pt);
144 type *type_setdim(type **,targ_size_t);
145 type *type_setdependent(type *t);
146 int type_isdependent(type *t);
147 void type_hydrate(type **);
148 void type_dehydrate(type **);
149 
150 version (SCPP)
151     targ_size_t type_size(type *);
152 version (HTOD)
153     targ_size_t type_size(type *);
154 
155 targ_size_t type_size(const type *);
156 uint type_alignsize(type *);
157 bool type_zeroSize(type *t, tym_t tyf);
158 uint type_parameterSize(type *t, tym_t tyf);
159 uint type_paramsize(type *t);
160 type *type_alloc(tym_t);
161 type *type_alloc_template(Symbol *s);
162 type *type_allocn(tym_t,type *tn);
163 type *type_allocmemptr(Classsym *stag,type *tn);
164 type *type_fake(tym_t);
165 type *type_setty(type **,uint);
166 type *type_settype(type **pt, type *t);
167 type *type_setmangle(type **pt,mangle_t mangle);
168 type *type_setcv(type **pt,tym_t cv);
169 int type_embed(type *t,type *u);
170 int type_isvla(type *t);
171 
172 param_t *param_calloc();
173 param_t *param_append_type(param_t **,type *);
174 void param_free_l(param_t *);
175 void param_free(param_t **);
176 Symbol *param_search(const(char)* name, param_t **pp);
177 void param_hydrate(param_t **);
178 void param_dehydrate(param_t **);
179 int typematch(type *t1, type *t2, int relax);
180 
181 type *type_pointer(type *tnext);
182 type *type_dyn_array(type *tnext);
183 extern (C) type *type_static_array(targ_size_t dim, type *tnext);
184 type *type_assoc_array(type *tkey, type *tvalue);
185 type *type_delegate(type *tnext);
186 extern (C) type *type_function(tym_t tyf, type*[] ptypes, bool variadic, type *tret);
187 type *type_enum(const(char) *name, type *tbase);
188 type *type_struct_class(const(char)* name, uint alignsize, uint structsize,
189         type *arg1type, type *arg2type, bool isUnion, bool isClass, bool isPOD, bool is0size);