1/* This file contains the definitions and documentation for the 2 tree codes used in GCC. 3 Copyright (C) 1987-2014 Free Software Foundation, Inc. 4 5This file is part of GCC. 6 7GCC is free software; you can redistribute it and/or modify it under 8the terms of the GNU General Public License as published by the Free 9Software Foundation; either version 3, or (at your option) any later 10version. 11 12GCC is distributed in the hope that it will be useful, but WITHOUT ANY 13WARRANTY; without even the implied warranty of MERCHANTABILITY or 14FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15for more details. 16 17You should have received a copy of the GNU General Public License 18along with GCC; see the file COPYING3. If not see 19<http://www.gnu.org/licenses/>. */ 20 21 22/* For tcc_references, tcc_expression, tcc_comparison, tcc_unary, 23 tcc_binary, and tcc_statement nodes, which use struct tree_exp, the 24 4th element is the number of argument slots to allocate. This 25 determines the size of the tree node object. Other nodes use 26 different structures, and the size is determined by the tree_union 27 member structure; the 4th element should be zero. Languages that 28 define language-specific tcc_exceptional or tcc_constant codes must 29 define the tree_size langhook to say how big they are. 30 31 These tree codes have been sorted so that the macros in tree.h that 32 check for various tree codes are optimized into range checks. This 33 gives a measurable performance improvement. When adding a new 34 code, consider its placement in relation to the other codes. */ 35 36/* Any erroneous construct is parsed into a node of this type. 37 This type of node is accepted without complaint in all contexts 38 by later parsing activities, to avoid multiple error messages 39 for one error. 40 No fields in these nodes are used except the TREE_CODE. */ 41DEFTREECODE (ERROR_MARK, "error_mark", tcc_exceptional, 0) 42 43/* Used to represent a name (such as, in the DECL_NAME of a decl node). 44 Internally it looks like a STRING_CST node. 45 There is only one IDENTIFIER_NODE ever made for any particular name. 46 Use `get_identifier' to get it (or create it, the first time). */ 47DEFTREECODE (IDENTIFIER_NODE, "identifier_node", tcc_exceptional, 0) 48 49/* Has the TREE_VALUE and TREE_PURPOSE fields. */ 50/* These nodes are made into lists by chaining through the 51 TREE_CHAIN field. The elements of the list live in the 52 TREE_VALUE fields, while TREE_PURPOSE fields are occasionally 53 used as well to get the effect of Lisp association lists. */ 54DEFTREECODE (TREE_LIST, "tree_list", tcc_exceptional, 0) 55 56/* These nodes contain an array of tree nodes. */ 57DEFTREECODE (TREE_VEC, "tree_vec", tcc_exceptional, 0) 58 59/* A symbol binding block. These are arranged in a tree, 60 where the BLOCK_SUBBLOCKS field contains a chain of subblocks 61 chained through the BLOCK_CHAIN field. 62 BLOCK_SUPERCONTEXT points to the parent block. 63 For a block which represents the outermost scope of a function, it 64 points to the FUNCTION_DECL node. 65 BLOCK_VARS points to a chain of decl nodes. 66 BLOCK_CHAIN points to the next BLOCK at the same level. 67 BLOCK_ABSTRACT_ORIGIN points to the original (abstract) tree node which 68 this block is an instance of, or else is NULL to indicate that this 69 block is not an instance of anything else. When non-NULL, the value 70 could either point to another BLOCK node or it could point to a 71 FUNCTION_DECL node (e.g. in the case of a block representing the 72 outermost scope of a particular inlining of a function). 73 BLOCK_ABSTRACT is nonzero if the block represents an abstract 74 instance of a block (i.e. one which is nested within an abstract 75 instance of an inline function). 76 TREE_ASM_WRITTEN is nonzero if the block was actually referenced 77 in the generated assembly. */ 78DEFTREECODE (BLOCK, "block", tcc_exceptional, 0) 79 80/* Each data type is represented by a tree node whose code is one of 81 the following: */ 82/* Each node that represents a data type has a component TYPE_SIZE 83 containing a tree that is an expression for the size in bits. 84 The TYPE_MODE contains the machine mode for values of this type. 85 The TYPE_POINTER_TO field contains a type for a pointer to this type, 86 or zero if no such has been created yet. 87 The TYPE_NEXT_VARIANT field is used to chain together types 88 that are variants made by type modifiers such as "const" and "volatile". 89 The TYPE_MAIN_VARIANT field, in any member of such a chain, 90 points to the start of the chain. 91 The TYPE_NAME field contains info on the name used in the program 92 for this type (for GDB symbol table output). It is either a 93 TYPE_DECL node, for types that are typedefs, or an IDENTIFIER_NODE 94 in the case of structs, unions or enums that are known with a tag, 95 or zero for types that have no special name. 96 The TYPE_CONTEXT for any sort of type which could have a name or 97 which could have named members (e.g. tagged types in C/C++) will 98 point to the node which represents the scope of the given type, or 99 will be NULL_TREE if the type has "file scope". For most types, this 100 will point to a BLOCK node or a FUNCTION_DECL node, but it could also 101 point to a FUNCTION_TYPE node (for types whose scope is limited to the 102 formal parameter list of some function type specification) or it 103 could point to a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE node 104 (for C++ "member" types). 105 For non-tagged-types, TYPE_CONTEXT need not be set to anything in 106 particular, since any type which is of some type category (e.g. 107 an array type or a function type) which cannot either have a name 108 itself or have named members doesn't really have a "scope" per se. 109 The TREE_CHAIN field is used as a forward-references to names for 110 ENUMERAL_TYPE, RECORD_TYPE, UNION_TYPE, and QUAL_UNION_TYPE nodes; 111 see below. */ 112 113/* The ordering of the following codes is optimized for the checking 114 macros in tree.h. Changing the order will degrade the speed of the 115 compiler. OFFSET_TYPE, ENUMERAL_TYPE, BOOLEAN_TYPE, INTEGER_TYPE, 116 REAL_TYPE, POINTER_TYPE. */ 117 118/* An offset is a pointer relative to an object. 119 The TREE_TYPE field is the type of the object at the offset. 120 The TYPE_OFFSET_BASETYPE points to the node for the type of object 121 that the offset is relative to. */ 122DEFTREECODE (OFFSET_TYPE, "offset_type", tcc_type, 0) 123 124/* C enums. The type node looks just like an INTEGER_TYPE node. 125 The symbols for the values of the enum type are defined by 126 CONST_DECL nodes, but the type does not point to them; 127 however, the TYPE_VALUES is a list in which each element's TREE_PURPOSE 128 is a name and the TREE_VALUE is the value (an INTEGER_CST node). */ 129/* A forward reference `enum foo' when no enum named foo is defined yet 130 has zero (a null pointer) in its TYPE_SIZE. The tag name is in 131 the TYPE_NAME field. If the type is later defined, the normal 132 fields are filled in. 133 RECORD_TYPE, UNION_TYPE, and QUAL_UNION_TYPE forward refs are 134 treated similarly. */ 135DEFTREECODE (ENUMERAL_TYPE, "enumeral_type", tcc_type, 0) 136 137/* Boolean type (true or false are the only values). Looks like an 138 INTEGRAL_TYPE. */ 139DEFTREECODE (BOOLEAN_TYPE, "boolean_type", tcc_type, 0) 140 141/* Integer types in all languages, including char in C. 142 Also used for sub-ranges of other discrete types. 143 Has components TYPE_MIN_VALUE, TYPE_MAX_VALUE (expressions, inclusive) 144 and TYPE_PRECISION (number of bits used by this type). 145 In the case of a subrange type in Pascal, the TREE_TYPE 146 of this will point at the supertype (another INTEGER_TYPE, 147 or an ENUMERAL_TYPE or BOOLEAN_TYPE). 148 Otherwise, the TREE_TYPE is zero. */ 149DEFTREECODE (INTEGER_TYPE, "integer_type", tcc_type, 0) 150 151/* C's float and double. Different floating types are distinguished 152 by machine mode and by the TYPE_SIZE and the TYPE_PRECISION. */ 153DEFTREECODE (REAL_TYPE, "real_type", tcc_type, 0) 154 155/* The ordering of the following codes is optimized for the checking 156 macros in tree.h. Changing the order will degrade the speed of the 157 compiler. POINTER_TYPE, REFERENCE_TYPE. Note that this range 158 overlaps the previous range of ordered types. */ 159 160/* All pointer-to-x types have code POINTER_TYPE. 161 The TREE_TYPE points to the node for the type pointed to. */ 162DEFTREECODE (POINTER_TYPE, "pointer_type", tcc_type, 0) 163 164/* A reference is like a pointer except that it is coerced 165 automatically to the value it points to. Used in C++. */ 166DEFTREECODE (REFERENCE_TYPE, "reference_type", tcc_type, 0) 167 168/* The C++ decltype(nullptr) type. */ 169DEFTREECODE (NULLPTR_TYPE, "nullptr_type", tcc_type, 0) 170 171/* _Fract and _Accum types in Embedded-C. Different fixed-point types 172 are distinguished by machine mode and by the TYPE_SIZE and the 173 TYPE_PRECISION. */ 174DEFTREECODE (FIXED_POINT_TYPE, "fixed_point_type", tcc_type, 0) 175 176/* The ordering of the following codes is optimized for the checking 177 macros in tree.h. Changing the order will degrade the speed of the 178 compiler. COMPLEX_TYPE, VECTOR_TYPE, ARRAY_TYPE. */ 179 180/* Complex number types. The TREE_TYPE field is the data type 181 of the real and imaginary parts. It must be of scalar 182 arithmetic type, not including pointer type. */ 183DEFTREECODE (COMPLEX_TYPE, "complex_type", tcc_type, 0) 184 185/* Vector types. The TREE_TYPE field is the data type of the vector 186 elements. The TYPE_PRECISION field is the number of subparts of 187 the vector. */ 188DEFTREECODE (VECTOR_TYPE, "vector_type", tcc_type, 0) 189 190/* The ordering of the following codes is optimized for the checking 191 macros in tree.h. Changing the order will degrade the speed of the 192 compiler. ARRAY_TYPE, RECORD_TYPE, UNION_TYPE, QUAL_UNION_TYPE. 193 Note that this range overlaps the previous range. */ 194 195/* Types of arrays. Special fields: 196 TREE_TYPE Type of an array element. 197 TYPE_DOMAIN Type to index by. 198 Its range of values specifies the array length. 199 The field TYPE_POINTER_TO (TREE_TYPE (array_type)) is always nonzero 200 and holds the type to coerce a value of that array type to in C. 201 TYPE_STRING_FLAG indicates a string (in contrast to an array of chars) 202 in languages (such as Chill) that make a distinction. */ 203/* Array types in C or Pascal */ 204DEFTREECODE (ARRAY_TYPE, "array_type", tcc_type, 0) 205 206/* Struct in C, or record in Pascal. */ 207/* Special fields: 208 TYPE_FIELDS chain of FIELD_DECLs for the fields of the struct, 209 and VAR_DECLs, TYPE_DECLs and CONST_DECLs for record-scope variables, 210 types and enumerators. 211 A few may need to be added for Pascal. */ 212/* See the comment above, before ENUMERAL_TYPE, for how 213 forward references to struct tags are handled in C. */ 214DEFTREECODE (RECORD_TYPE, "record_type", tcc_type, 0) 215 216/* Union in C. Like a struct, except that the offsets of the fields 217 will all be zero. */ 218/* See the comment above, before ENUMERAL_TYPE, for how 219 forward references to union tags are handled in C. */ 220DEFTREECODE (UNION_TYPE, "union_type", tcc_type, 0) /* C union type */ 221 222/* Similar to UNION_TYPE, except that the expressions in DECL_QUALIFIER 223 in each FIELD_DECL determine what the union contains. The first 224 field whose DECL_QUALIFIER expression is true is deemed to occupy 225 the union. */ 226DEFTREECODE (QUAL_UNION_TYPE, "qual_union_type", tcc_type, 0) 227 228/* The ordering of the following codes is optimized for the checking 229 macros in tree.h. Changing the order will degrade the speed of the 230 compiler. VOID_TYPE, FUNCTION_TYPE, METHOD_TYPE. */ 231 232/* The void type in C */ 233DEFTREECODE (VOID_TYPE, "void_type", tcc_type, 0) 234 235/* Type of functions. Special fields: 236 TREE_TYPE type of value returned. 237 TYPE_ARG_TYPES list of types of arguments expected. 238 this list is made of TREE_LIST nodes. 239 Types of "Procedures" in languages where they are different from functions 240 have code FUNCTION_TYPE also, but then TREE_TYPE is zero or void type. */ 241DEFTREECODE (FUNCTION_TYPE, "function_type", tcc_type, 0) 242 243/* METHOD_TYPE is the type of a function which takes an extra first 244 argument for "self", which is not present in the declared argument list. 245 The TREE_TYPE is the return type of the method. The TYPE_METHOD_BASETYPE 246 is the type of "self". TYPE_ARG_TYPES is the real argument list, which 247 includes the hidden argument for "self". */ 248DEFTREECODE (METHOD_TYPE, "method_type", tcc_type, 0) 249 250/* This is a language-specific kind of type. 251 Its meaning is defined by the language front end. 252 layout_type does not know how to lay this out, 253 so the front-end must do so manually. */ 254DEFTREECODE (LANG_TYPE, "lang_type", tcc_type, 0) 255 256/* Expressions */ 257 258/* First, the constants. */ 259 260/* Contents are in TREE_INT_CST_LOW and TREE_INT_CST_HIGH fields, 261 32 bits each, giving us a 64 bit constant capability. INTEGER_CST 262 nodes can be shared, and therefore should be considered read only. 263 They should be copied, before setting a flag such as TREE_OVERFLOW. 264 If an INTEGER_CST has TREE_OVERFLOW already set, it is known to be unique. 265 INTEGER_CST nodes are created for the integral types, for pointer 266 types and for vector and float types in some circumstances. */ 267DEFTREECODE (INTEGER_CST, "integer_cst", tcc_constant, 0) 268 269/* Contents are in TREE_REAL_CST field. */ 270DEFTREECODE (REAL_CST, "real_cst", tcc_constant, 0) 271 272/* Contents are in TREE_FIXED_CST field. */ 273DEFTREECODE (FIXED_CST, "fixed_cst", tcc_constant, 0) 274 275/* Contents are in TREE_REALPART and TREE_IMAGPART fields, 276 whose contents are other constant nodes. */ 277DEFTREECODE (COMPLEX_CST, "complex_cst", tcc_constant, 0) 278 279/* Contents are in TREE_VECTOR_CST_ELTS field. */ 280DEFTREECODE (VECTOR_CST, "vector_cst", tcc_constant, 0) 281 282/* Contents are TREE_STRING_LENGTH and the actual contents of the string. */ 283DEFTREECODE (STRING_CST, "string_cst", tcc_constant, 0) 284 285/* Declarations. All references to names are represented as ..._DECL 286 nodes. The decls in one binding context are chained through the 287 TREE_CHAIN field. Each DECL has a DECL_NAME field which contains 288 an IDENTIFIER_NODE. (Some decls, most often labels, may have zero 289 as the DECL_NAME). DECL_CONTEXT points to the node representing 290 the context in which this declaration has its scope. For 291 FIELD_DECLs, this is the RECORD_TYPE, UNION_TYPE, or 292 QUAL_UNION_TYPE node that the field is a member of. For VAR_DECL, 293 PARM_DECL, FUNCTION_DECL, LABEL_DECL, and CONST_DECL nodes, this 294 points to either the FUNCTION_DECL for the containing function, the 295 RECORD_TYPE or UNION_TYPE for the containing type, or NULL_TREE or 296 a TRANSLATION_UNIT_DECL if the given decl has "file scope". 297 DECL_ABSTRACT_ORIGIN, if non-NULL, points to the original (abstract) 298 ..._DECL node of which this decl is an (inlined or template expanded) 299 instance. 300 The TREE_TYPE field holds the data type of the object, when relevant. 301 LABEL_DECLs have no data type. For TYPE_DECL, the TREE_TYPE field 302 contents are the type whose name is being declared. 303 The DECL_ALIGN, DECL_SIZE, 304 and DECL_MODE fields exist in decl nodes just as in type nodes. 305 They are unused in LABEL_DECL, TYPE_DECL and CONST_DECL nodes. 306 307 DECL_FIELD_BIT_OFFSET holds an integer number of bits offset for 308 the location. DECL_VOFFSET holds an expression for a variable 309 offset; it is to be multiplied by DECL_VOFFSET_UNIT (an integer). 310 These fields are relevant only in FIELD_DECLs and PARM_DECLs. 311 312 DECL_INITIAL holds the value to initialize a variable to, 313 or the value of a constant. For a function, it holds the body 314 (a node of type BLOCK representing the function's binding contour 315 and whose body contains the function's statements.) For a LABEL_DECL 316 in C, it is a flag, nonzero if the label's definition has been seen. 317 318 PARM_DECLs use a special field: 319 DECL_ARG_TYPE is the type in which the argument is actually 320 passed, which may be different from its type within the function. 321 322 FUNCTION_DECLs use four special fields: 323 DECL_ARGUMENTS holds a chain of PARM_DECL nodes for the arguments. 324 DECL_RESULT holds a RESULT_DECL node for the value of a function. 325 The DECL_RTL field is 0 for a function that returns no value. 326 (C functions returning void have zero here.) 327 The TREE_TYPE field is the type in which the result is actually 328 returned. This is usually the same as the return type of the 329 FUNCTION_DECL, but it may be a wider integer type because of 330 promotion. 331 DECL_FUNCTION_CODE is a code number that is nonzero for 332 built-in functions. Its value is an enum built_in_function 333 that says which built-in function it is. 334 335 DECL_SOURCE_FILE holds a filename string and DECL_SOURCE_LINE 336 holds a line number. In some cases these can be the location of 337 a reference, if no definition has been seen. 338 339 DECL_ABSTRACT is nonzero if the decl represents an abstract instance 340 of a decl (i.e. one which is nested within an abstract instance of a 341 inline function. */ 342 343DEFTREECODE (FUNCTION_DECL, "function_decl", tcc_declaration, 0) 344DEFTREECODE (LABEL_DECL, "label_decl", tcc_declaration, 0) 345/* The ordering of the following codes is optimized for the checking 346 macros in tree.h. Changing the order will degrade the speed of the 347 compiler. FIELD_DECL, VAR_DECL, CONST_DECL, PARM_DECL, 348 TYPE_DECL. */ 349DEFTREECODE (FIELD_DECL, "field_decl", tcc_declaration, 0) 350DEFTREECODE (VAR_DECL, "var_decl", tcc_declaration, 0) 351DEFTREECODE (CONST_DECL, "const_decl", tcc_declaration, 0) 352DEFTREECODE (PARM_DECL, "parm_decl", tcc_declaration, 0) 353DEFTREECODE (TYPE_DECL, "type_decl", tcc_declaration, 0) 354DEFTREECODE (RESULT_DECL, "result_decl", tcc_declaration, 0) 355 356/* A "declaration" of a debug temporary. It should only appear in 357 DEBUG stmts. */ 358DEFTREECODE (DEBUG_EXPR_DECL, "debug_expr_decl", tcc_declaration, 0) 359 360/* A namespace declaration. Namespaces appear in DECL_CONTEXT of other 361 _DECLs, providing a hierarchy of names. */ 362DEFTREECODE (NAMESPACE_DECL, "namespace_decl", tcc_declaration, 0) 363 364/* A declaration import. 365 The C++ FE uses this to represent a using-directive; eg: 366 "using namespace foo". 367 But it could be used to represent any declaration import construct. 368 Whenever a declaration import appears in a lexical block, the BLOCK node 369 representing that lexical block in GIMPLE will contain an IMPORTED_DECL 370 node, linked via BLOCK_VARS accessor of the said BLOCK. 371 For a given NODE which code is IMPORTED_DECL, 372 IMPORTED_DECL_ASSOCIATED_DECL (NODE) accesses the imported declaration. */ 373DEFTREECODE (IMPORTED_DECL, "imported_decl", tcc_declaration, 0) 374 375/* A namelist declaration. 376 The Fortran FE uses this to represent a namelist statement, e.g.: 377 NAMELIST /namelist-group-name/ namelist-group-object-list. 378 Whenever a declaration import appears in a lexical block, the BLOCK node 379 representing that lexical block in GIMPLE will contain an NAMELIST_DECL 380 node, linked via BLOCK_VARS accessor of the said BLOCK. 381 For a given NODE which code is NAMELIST_DECL, 382 NAMELIST_DECL_ASSOCIATED_DECL (NODE) accesses the imported declaration. */ 383DEFTREECODE (NAMELIST_DECL, "namelist_decl", tcc_declaration, 0) 384 385/* A translation unit. This is not technically a declaration, since it 386 can't be looked up, but it's close enough. */ 387DEFTREECODE (TRANSLATION_UNIT_DECL, "translation_unit_decl",\ 388 tcc_declaration, 0) 389 390/* References to storage. */ 391 392/* The ordering of the following codes is optimized for the classification 393 in handled_component_p. Keep them in a consecutive group. */ 394 395/* Value is structure or union component. 396 Operand 0 is the structure or union (an expression). 397 Operand 1 is the field (a node of type FIELD_DECL). 398 Operand 2, if present, is the value of DECL_FIELD_OFFSET, measured 399 in units of DECL_OFFSET_ALIGN / BITS_PER_UNIT. */ 400DEFTREECODE (COMPONENT_REF, "component_ref", tcc_reference, 3) 401 402/* Reference to a group of bits within an object. Similar to COMPONENT_REF 403 except the position is given explicitly rather than via a FIELD_DECL. 404 Operand 0 is the structure or union expression; 405 operand 1 is a tree giving the constant number of bits being referenced; 406 operand 2 is a tree giving the constant position of the first referenced bit. 407 The result type width has to match the number of bits referenced. 408 If the result type is integral, its signedness specifies how it is extended 409 to its mode width. */ 410DEFTREECODE (BIT_FIELD_REF, "bit_field_ref", tcc_reference, 3) 411 412/* Array indexing. 413 Operand 0 is the array; operand 1 is a (single) array index. 414 Operand 2, if present, is a copy of TYPE_MIN_VALUE of the index. 415 Operand 3, if present, is the element size, measured in units of 416 the alignment of the element type. */ 417DEFTREECODE (ARRAY_REF, "array_ref", tcc_reference, 4) 418 419/* Likewise, except that the result is a range ("slice") of the array. The 420 starting index of the resulting array is taken from operand 1 and the size 421 of the range is taken from the type of the expression. */ 422DEFTREECODE (ARRAY_RANGE_REF, "array_range_ref", tcc_reference, 4) 423 424/* Used only on an operand of complex type, these return 425 a value of the corresponding component type. */ 426DEFTREECODE (REALPART_EXPR, "realpart_expr", tcc_reference, 1) 427DEFTREECODE (IMAGPART_EXPR, "imagpart_expr", tcc_reference, 1) 428 429/* Represents viewing something of one type as being of a second type. 430 This corresponds to an "Unchecked Conversion" in Ada and roughly to 431 the idiom *(type2 *)&X in C. The only operand is the value to be 432 viewed as being of another type. It is undefined if the type of the 433 input and of the expression have different sizes. 434 435 This code may also be used within the LHS of a MODIFY_EXPR, in which 436 case no actual data motion may occur. TREE_ADDRESSABLE will be set in 437 this case and GCC must abort if it could not do the operation without 438 generating insns. */ 439DEFTREECODE (VIEW_CONVERT_EXPR, "view_convert_expr", tcc_reference, 1) 440 441/* C unary `*' or Pascal `^'. One operand, an expression for a pointer. */ 442DEFTREECODE (INDIRECT_REF, "indirect_ref", tcc_reference, 1) 443 444/* Used to represent lookup in a virtual method table which is dependent on 445 the runtime type of an object. Operands are: 446 OBJ_TYPE_REF_EXPR: An expression that evaluates the value to use. 447 OBJ_TYPE_REF_OBJECT: Is the object on whose behalf the lookup is 448 being performed. Through this the optimizers may be able to statically 449 determine the dynamic type of the object. 450 OBJ_TYPE_REF_TOKEN: An integer index to the virtual method table. */ 451DEFTREECODE (OBJ_TYPE_REF, "obj_type_ref", tcc_expression, 3) 452 453/* Used to represent the brace-enclosed initializers for a structure or an 454 array. It contains a sequence of component values made out of a VEC of 455 constructor_elt. 456 457 For RECORD_TYPE, UNION_TYPE, or QUAL_UNION_TYPE: 458 The field INDEX of each constructor_elt is a FIELD_DECL. 459 460 For ARRAY_TYPE: 461 The field INDEX of each constructor_elt is the corresponding index. 462 If the index is a RANGE_EXPR, it is a short-hand for many nodes, 463 one for each index in the range. (If the corresponding field VALUE 464 has side-effects, they are evaluated once for each element. Wrap the 465 value in a SAVE_EXPR if you want to evaluate side effects only once.) 466 467 Components that aren't present are cleared as per the C semantics, 468 unless the CONSTRUCTOR_NO_CLEARING flag is set, in which case their 469 value becomes undefined. */ 470DEFTREECODE (CONSTRUCTOR, "constructor", tcc_exceptional, 0) 471 472/* The expression types are mostly straightforward, with the fourth argument 473 of DEFTREECODE saying how many operands there are. 474 Unless otherwise specified, the operands are expressions and the 475 types of all the operands and the expression must all be the same. */ 476 477/* Contains two expressions to compute, one followed by the other. 478 the first value is ignored. The second one's value is used. The 479 type of the first expression need not agree with the other types. */ 480DEFTREECODE (COMPOUND_EXPR, "compound_expr", tcc_expression, 2) 481 482/* Assignment expression. Operand 0 is the what to set; 1, the new value. */ 483DEFTREECODE (MODIFY_EXPR, "modify_expr", tcc_expression, 2) 484 485/* Initialization expression. Operand 0 is the variable to initialize; 486 Operand 1 is the initializer. This differs from MODIFY_EXPR in that any 487 reference to the referent of operand 0 within operand 1 is undefined. */ 488DEFTREECODE (INIT_EXPR, "init_expr", tcc_expression, 2) 489 490/* For TARGET_EXPR, operand 0 is the target of an initialization, 491 operand 1 is the initializer for the target, which may be void 492 if simply expanding it initializes the target. 493 operand 2 is the cleanup for this node, if any. 494 operand 3 is the saved initializer after this node has been 495 expanded once; this is so we can re-expand the tree later. */ 496DEFTREECODE (TARGET_EXPR, "target_expr", tcc_expression, 4) 497 498/* Conditional expression ( ... ? ... : ... in C). 499 Operand 0 is the condition. 500 Operand 1 is the then-value. 501 Operand 2 is the else-value. 502 Operand 0 may be of any type. 503 Operand 1 must have the same type as the entire expression, unless 504 it unconditionally throws an exception, in which case it should 505 have VOID_TYPE. The same constraints apply to operand 2. The 506 condition in operand 0 must be of integral type. 507 508 In cfg gimple, if you do not have a selection expression, operands 509 1 and 2 are NULL. The operands are then taken from the cfg edges. */ 510DEFTREECODE (COND_EXPR, "cond_expr", tcc_expression, 3) 511 512/* Vector conditional expression. It is like COND_EXPR, but with 513 vector operands. 514 515 A = VEC_COND_EXPR ( X < Y, B, C) 516 517 means 518 519 for (i=0; i<N; i++) 520 A[i] = X[i] < Y[i] ? B[i] : C[i]; 521*/ 522DEFTREECODE (VEC_COND_EXPR, "vec_cond_expr", tcc_expression, 3) 523 524/* Vector permutation expression. A = VEC_PERM_EXPR<v0, v1, mask> means 525 526 N = length(mask) 527 foreach i in N: 528 M = mask[i] % (2*N) 529 A = M < N ? v0[M] : v1[M-N] 530 531 V0 and V1 are vectors of the same type. MASK is an integer-typed 532 vector. The number of MASK elements must be the same with the 533 number of elements in V0 and V1. The size of the inner type 534 of the MASK and of the V0 and V1 must be the same. 535*/ 536DEFTREECODE (VEC_PERM_EXPR, "vec_perm_expr", tcc_expression, 3) 537 538/* Declare local variables, including making RTL and allocating space. 539 BIND_EXPR_VARS is a chain of VAR_DECL nodes for the variables. 540 BIND_EXPR_BODY is the body, the expression to be computed using 541 the variables. The value of operand 1 becomes that of the BIND_EXPR. 542 BIND_EXPR_BLOCK is the BLOCK that corresponds to these bindings 543 for debugging purposes. If this BIND_EXPR is actually expanded, 544 that sets the TREE_USED flag in the BLOCK. 545 546 The BIND_EXPR is not responsible for informing parsers 547 about these variables. If the body is coming from the input file, 548 then the code that creates the BIND_EXPR is also responsible for 549 informing the parser of the variables. 550 551 If the BIND_EXPR is ever expanded, its TREE_USED flag is set. 552 This tells the code for debugging symbol tables not to ignore the BIND_EXPR. 553 If the BIND_EXPR should be output for debugging but will not be expanded, 554 set the TREE_USED flag by hand. 555 556 In order for the BIND_EXPR to be known at all, the code that creates it 557 must also install it as a subblock in the tree of BLOCK 558 nodes for the function. */ 559DEFTREECODE (BIND_EXPR, "bind_expr", tcc_expression, 3) 560 561/* Function call. CALL_EXPRs are represented by variably-sized expression 562 nodes. There are at least three fixed operands. Operand 0 is an 563 INTEGER_CST node containing the total operand count, the number of 564 arguments plus 3. Operand 1 is the function, while operand 2 is 565 is static chain argument, or NULL. The remaining operands are the 566 arguments to the call. */ 567DEFTREECODE (CALL_EXPR, "call_expr", tcc_vl_exp, 3) 568 569/* Specify a value to compute along with its corresponding cleanup. 570 Operand 0 is the cleanup expression. 571 The cleanup is executed by the first enclosing CLEANUP_POINT_EXPR, 572 which must exist. This differs from TRY_CATCH_EXPR in that operand 1 573 is always evaluated when cleanups are run. */ 574DEFTREECODE (WITH_CLEANUP_EXPR, "with_cleanup_expr", tcc_expression, 1) 575 576/* Specify a cleanup point. 577 Operand 0 is an expression that may have cleanups. If it does, those 578 cleanups are executed after the expression is expanded. 579 580 Note that if the expression is a reference to storage, it is forced out 581 of memory before the cleanups are run. This is necessary to handle 582 cases where the cleanups modify the storage referenced; in the 583 expression 't.i', if 't' is a struct with an integer member 'i' and a 584 cleanup which modifies 'i', the value of the expression depends on 585 whether the cleanup is run before or after 't.i' is evaluated. When 586 expand_expr is run on 't.i', it returns a MEM. This is not good enough; 587 the value of 't.i' must be forced out of memory. 588 589 As a consequence, the operand of a CLEANUP_POINT_EXPR must not have 590 BLKmode, because it will not be forced out of memory. */ 591DEFTREECODE (CLEANUP_POINT_EXPR, "cleanup_point_expr", tcc_expression, 1) 592 593/* The following code is used in languages that have types where some 594 field in an object of the type contains a value that is used in the 595 computation of another field's offset or size and/or the size of the 596 type. The positions and/or sizes of fields can vary from object to 597 object of the same type or even for one and the same object within 598 its scope. 599 600 Record types with discriminants in Ada or schema types in Pascal are 601 examples of such types. This mechanism is also used to create "fat 602 pointers" for unconstrained array types in Ada; the fat pointer is a 603 structure one of whose fields is a pointer to the actual array type 604 and the other field is a pointer to a template, which is a structure 605 containing the bounds of the array. The bounds in the type pointed 606 to by the first field in the fat pointer refer to the values in the 607 template. 608 609 When you wish to construct such a type you need "self-references" 610 that allow you to reference the object having this type from the 611 TYPE node, i.e. without having a variable instantiating this type. 612 613 Such a "self-references" is done using a PLACEHOLDER_EXPR. This is 614 a node that will later be replaced with the object being referenced. 615 Its type is that of the object and selects which object to use from 616 a chain of references (see below). No other slots are used in the 617 PLACEHOLDER_EXPR. 618 619 For example, if your type FOO is a RECORD_TYPE with a field BAR, 620 and you need the value of <variable>.BAR to calculate TYPE_SIZE 621 (FOO), just substitute <variable> above with a PLACEHOLDER_EXPR 622 whose TREE_TYPE is FOO. Then construct your COMPONENT_REF with 623 the PLACEHOLDER_EXPR as the first operand (which has the correct 624 type). Later, when the size is needed in the program, the back-end 625 will find this PLACEHOLDER_EXPR and generate code to calculate the 626 actual size at run-time. In the following, we describe how this 627 calculation is done. 628 629 When we wish to evaluate a size or offset, we check whether it contains a 630 PLACEHOLDER_EXPR. If it does, we call substitute_placeholder_in_expr 631 passing both that tree and an expression within which the object may be 632 found. The latter expression is the object itself in the simple case of 633 an Ada record with discriminant, but it can be the array in the case of an 634 unconstrained array. 635 636 In the latter case, we need the fat pointer, because the bounds of 637 the array can only be accessed from it. However, we rely here on the 638 fact that the expression for the array contains the dereference of 639 the fat pointer that obtained the array pointer. */ 640 641/* Denotes a record to later be substituted before evaluating this expression. 642 The type of this expression is used to find the record to replace it. */ 643DEFTREECODE (PLACEHOLDER_EXPR, "placeholder_expr", tcc_exceptional, 0) 644 645/* Simple arithmetic. */ 646DEFTREECODE (PLUS_EXPR, "plus_expr", tcc_binary, 2) 647DEFTREECODE (MINUS_EXPR, "minus_expr", tcc_binary, 2) 648DEFTREECODE (MULT_EXPR, "mult_expr", tcc_binary, 2) 649 650/* Pointer addition. The first operand is always a pointer and the 651 second operand is an integer of type sizetype. */ 652DEFTREECODE (POINTER_PLUS_EXPR, "pointer_plus_expr", tcc_binary, 2) 653 654/* Highpart multiplication. For an integral type with precision B, 655 returns bits [2B-1, B] of the full 2*B product. */ 656DEFTREECODE (MULT_HIGHPART_EXPR, "mult_highpart_expr", tcc_binary, 2) 657 658/* Division for integer result that rounds the quotient toward zero. */ 659DEFTREECODE (TRUNC_DIV_EXPR, "trunc_div_expr", tcc_binary, 2) 660 661/* Division for integer result that rounds the quotient toward infinity. */ 662DEFTREECODE (CEIL_DIV_EXPR, "ceil_div_expr", tcc_binary, 2) 663 664/* Division for integer result that rounds toward minus infinity. */ 665DEFTREECODE (FLOOR_DIV_EXPR, "floor_div_expr", tcc_binary, 2) 666 667/* Division for integer result that rounds toward nearest integer. */ 668DEFTREECODE (ROUND_DIV_EXPR, "round_div_expr", tcc_binary, 2) 669 670/* Four kinds of remainder that go with the four kinds of division. */ 671DEFTREECODE (TRUNC_MOD_EXPR, "trunc_mod_expr", tcc_binary, 2) 672DEFTREECODE (CEIL_MOD_EXPR, "ceil_mod_expr", tcc_binary, 2) 673DEFTREECODE (FLOOR_MOD_EXPR, "floor_mod_expr", tcc_binary, 2) 674DEFTREECODE (ROUND_MOD_EXPR, "round_mod_expr", tcc_binary, 2) 675 676/* Division for real result. */ 677DEFTREECODE (RDIV_EXPR, "rdiv_expr", tcc_binary, 2) 678 679/* Division which is not supposed to need rounding. 680 Used for pointer subtraction in C. */ 681DEFTREECODE (EXACT_DIV_EXPR, "exact_div_expr", tcc_binary, 2) 682 683/* Conversion of real to fixed point by truncation. */ 684DEFTREECODE (FIX_TRUNC_EXPR, "fix_trunc_expr", tcc_unary, 1) 685 686/* Conversion of an integer to a real. */ 687DEFTREECODE (FLOAT_EXPR, "float_expr", tcc_unary, 1) 688 689/* Unary negation. */ 690DEFTREECODE (NEGATE_EXPR, "negate_expr", tcc_unary, 1) 691 692/* Minimum and maximum values. When used with floating point, if both 693 operands are zeros, or if either operand is NaN, then it is unspecified 694 which of the two operands is returned as the result. */ 695DEFTREECODE (MIN_EXPR, "min_expr", tcc_binary, 2) 696DEFTREECODE (MAX_EXPR, "max_expr", tcc_binary, 2) 697 698/* Represents the absolute value of the operand. 699 700 An ABS_EXPR must have either an INTEGER_TYPE or a REAL_TYPE. The 701 operand of the ABS_EXPR must have the same type. */ 702DEFTREECODE (ABS_EXPR, "abs_expr", tcc_unary, 1) 703 704/* Shift operations for shift and rotate. 705 Shift means logical shift if done on an 706 unsigned type, arithmetic shift if done on a signed type. 707 The second operand is the number of bits to 708 shift by; it need not be the same type as the first operand and result. 709 Note that the result is undefined if the second operand is larger 710 than or equal to the first operand's type size. 711 712 The first operand of a shift can have either an integer or a 713 (non-integer) fixed-point type. We follow the ISO/IEC TR 18037:2004 714 semantics for the latter. 715 716 Rotates are defined for integer types only. */ 717DEFTREECODE (LSHIFT_EXPR, "lshift_expr", tcc_binary, 2) 718DEFTREECODE (RSHIFT_EXPR, "rshift_expr", tcc_binary, 2) 719DEFTREECODE (LROTATE_EXPR, "lrotate_expr", tcc_binary, 2) 720DEFTREECODE (RROTATE_EXPR, "rrotate_expr", tcc_binary, 2) 721 722/* Bitwise operations. Operands have same mode as result. */ 723DEFTREECODE (BIT_IOR_EXPR, "bit_ior_expr", tcc_binary, 2) 724DEFTREECODE (BIT_XOR_EXPR, "bit_xor_expr", tcc_binary, 2) 725DEFTREECODE (BIT_AND_EXPR, "bit_and_expr", tcc_binary, 2) 726DEFTREECODE (BIT_NOT_EXPR, "bit_not_expr", tcc_unary, 1) 727 728/* ANDIF and ORIF allow the second operand not to be computed if the 729 value of the expression is determined from the first operand. AND, 730 OR, and XOR always compute the second operand whether its value is 731 needed or not (for side effects). The operand may have 732 BOOLEAN_TYPE or INTEGER_TYPE. In either case, the argument will be 733 either zero or one. For example, a TRUTH_NOT_EXPR will never have 734 an INTEGER_TYPE VAR_DECL as its argument; instead, a NE_EXPR will be 735 used to compare the VAR_DECL to zero, thereby obtaining a node with 736 value zero or one. */ 737DEFTREECODE (TRUTH_ANDIF_EXPR, "truth_andif_expr", tcc_expression, 2) 738DEFTREECODE (TRUTH_ORIF_EXPR, "truth_orif_expr", tcc_expression, 2) 739DEFTREECODE (TRUTH_AND_EXPR, "truth_and_expr", tcc_expression, 2) 740DEFTREECODE (TRUTH_OR_EXPR, "truth_or_expr", tcc_expression, 2) 741DEFTREECODE (TRUTH_XOR_EXPR, "truth_xor_expr", tcc_expression, 2) 742DEFTREECODE (TRUTH_NOT_EXPR, "truth_not_expr", tcc_expression, 1) 743 744/* Relational operators. 745 `EQ_EXPR' and `NE_EXPR' are allowed for any types. 746 The others are allowed only for integer (or pointer or enumeral) 747 or real types. 748 In all cases the operands will have the same type, 749 and the value is either the type used by the language for booleans 750 or an integer vector type of the same size and with the same number 751 of elements as the comparison operands. True for a vector of 752 comparison results has all bits set while false is equal to zero. */ 753DEFTREECODE (LT_EXPR, "lt_expr", tcc_comparison, 2) 754DEFTREECODE (LE_EXPR, "le_expr", tcc_comparison, 2) 755DEFTREECODE (GT_EXPR, "gt_expr", tcc_comparison, 2) 756DEFTREECODE (GE_EXPR, "ge_expr", tcc_comparison, 2) 757DEFTREECODE (EQ_EXPR, "eq_expr", tcc_comparison, 2) 758DEFTREECODE (NE_EXPR, "ne_expr", tcc_comparison, 2) 759 760/* Additional relational operators for floating point unordered. */ 761DEFTREECODE (UNORDERED_EXPR, "unordered_expr", tcc_comparison, 2) 762DEFTREECODE (ORDERED_EXPR, "ordered_expr", tcc_comparison, 2) 763 764/* These are equivalent to unordered or ... */ 765DEFTREECODE (UNLT_EXPR, "unlt_expr", tcc_comparison, 2) 766DEFTREECODE (UNLE_EXPR, "unle_expr", tcc_comparison, 2) 767DEFTREECODE (UNGT_EXPR, "ungt_expr", tcc_comparison, 2) 768DEFTREECODE (UNGE_EXPR, "unge_expr", tcc_comparison, 2) 769DEFTREECODE (UNEQ_EXPR, "uneq_expr", tcc_comparison, 2) 770 771/* This is the reverse of uneq_expr. */ 772DEFTREECODE (LTGT_EXPR, "ltgt_expr", tcc_comparison, 2) 773 774DEFTREECODE (RANGE_EXPR, "range_expr", tcc_binary, 2) 775 776/* Represents a re-association barrier for floating point expressions 777 like explicit parenthesis in fortran. */ 778DEFTREECODE (PAREN_EXPR, "paren_expr", tcc_unary, 1) 779 780/* Represents a conversion of type of a value. 781 All conversions, including implicit ones, must be 782 represented by CONVERT_EXPR or NOP_EXPR nodes. */ 783DEFTREECODE (CONVERT_EXPR, "convert_expr", tcc_unary, 1) 784 785/* Conversion of a pointer value to a pointer to a different 786 address space. */ 787DEFTREECODE (ADDR_SPACE_CONVERT_EXPR, "addr_space_convert_expr", tcc_unary, 1) 788 789/* Conversion of a fixed-point value to an integer, a real, or a fixed-point 790 value. Or conversion of a fixed-point value from an integer, a real, or 791 a fixed-point value. */ 792DEFTREECODE (FIXED_CONVERT_EXPR, "fixed_convert_expr", tcc_unary, 1) 793 794/* Represents a conversion expected to require no code to be generated. */ 795DEFTREECODE (NOP_EXPR, "nop_expr", tcc_unary, 1) 796 797/* Value is same as argument, but guaranteed not an lvalue. */ 798DEFTREECODE (NON_LVALUE_EXPR, "non_lvalue_expr", tcc_unary, 1) 799 800/* A COMPOUND_LITERAL_EXPR represents a literal that is placed in a DECL. The 801 COMPOUND_LITERAL_EXPR_DECL_EXPR is the a DECL_EXPR containing the decl 802 for the anonymous object represented by the COMPOUND_LITERAL; 803 the DECL_INITIAL of that decl is the CONSTRUCTOR that initializes 804 the compound literal. */ 805DEFTREECODE (COMPOUND_LITERAL_EXPR, "compound_literal_expr", tcc_expression, 1) 806 807/* Represents something we computed once and will use multiple times. 808 First operand is that expression. After it is evaluated once, it 809 will be replaced by the temporary variable that holds the value. */ 810DEFTREECODE (SAVE_EXPR, "save_expr", tcc_expression, 1) 811 812/* & in C. Value is the address at which the operand's value resides. 813 Operand may have any mode. Result mode is Pmode. */ 814DEFTREECODE (ADDR_EXPR, "addr_expr", tcc_expression, 1) 815 816/* Operand0 is a function constant; result is part N of a function 817 descriptor of type ptr_mode. */ 818DEFTREECODE (FDESC_EXPR, "fdesc_expr", tcc_expression, 2) 819 820/* Given two real or integer operands of the same type, 821 returns a complex value of the corresponding complex type. */ 822DEFTREECODE (COMPLEX_EXPR, "complex_expr", tcc_binary, 2) 823 824/* Complex conjugate of operand. Used only on complex types. */ 825DEFTREECODE (CONJ_EXPR, "conj_expr", tcc_unary, 1) 826 827/* Nodes for ++ and -- in C. 828 The second arg is how much to increment or decrement by. 829 For a pointer, it would be the size of the object pointed to. */ 830DEFTREECODE (PREDECREMENT_EXPR, "predecrement_expr", tcc_expression, 2) 831DEFTREECODE (PREINCREMENT_EXPR, "preincrement_expr", tcc_expression, 2) 832DEFTREECODE (POSTDECREMENT_EXPR, "postdecrement_expr", tcc_expression, 2) 833DEFTREECODE (POSTINCREMENT_EXPR, "postincrement_expr", tcc_expression, 2) 834 835/* Used to implement `va_arg'. */ 836DEFTREECODE (VA_ARG_EXPR, "va_arg_expr", tcc_expression, 1) 837 838/* Evaluate operand 1. If and only if an exception is thrown during 839 the evaluation of operand 1, evaluate operand 2. 840 841 This differs from TRY_FINALLY_EXPR in that operand 2 is not evaluated 842 on a normal or jump exit, only on an exception. */ 843DEFTREECODE (TRY_CATCH_EXPR, "try_catch_expr", tcc_statement, 2) 844 845/* Evaluate the first operand. 846 The second operand is a cleanup expression which is evaluated 847 on any exit (normal, exception, or jump out) from this expression. */ 848DEFTREECODE (TRY_FINALLY_EXPR, "try_finally", tcc_statement, 2) 849 850/* These types of expressions have no useful value, 851 and always have side effects. */ 852 853/* Used to represent a local declaration. The operand is DECL_EXPR_DECL. */ 854DEFTREECODE (DECL_EXPR, "decl_expr", tcc_statement, 1) 855 856/* A label definition, encapsulated as a statement. 857 Operand 0 is the LABEL_DECL node for the label that appears here. 858 The type should be void and the value should be ignored. */ 859DEFTREECODE (LABEL_EXPR, "label_expr", tcc_statement, 1) 860 861/* GOTO. Operand 0 is a LABEL_DECL node or an expression. 862 The type should be void and the value should be ignored. */ 863DEFTREECODE (GOTO_EXPR, "goto_expr", tcc_statement, 1) 864 865/* RETURN. Evaluates operand 0, then returns from the current function. 866 Presumably that operand is an assignment that stores into the 867 RESULT_DECL that hold the value to be returned. 868 The operand may be null. 869 The type should be void and the value should be ignored. */ 870DEFTREECODE (RETURN_EXPR, "return_expr", tcc_statement, 1) 871 872/* Exit the inner most loop conditionally. Operand 0 is the condition. 873 The type should be void and the value should be ignored. */ 874DEFTREECODE (EXIT_EXPR, "exit_expr", tcc_statement, 1) 875 876/* A loop. Operand 0 is the body of the loop. 877 It must contain an EXIT_EXPR or is an infinite loop. 878 The type should be void and the value should be ignored. */ 879DEFTREECODE (LOOP_EXPR, "loop_expr", tcc_statement, 1) 880 881/* Switch expression. 882 883 TREE_TYPE is the original type of the condition, before any 884 language required type conversions. It may be NULL, in which case 885 the original type and final types are assumed to be the same. 886 887 Operand 0 is the expression used to perform the branch, 888 Operand 1 is the body of the switch, which probably contains 889 CASE_LABEL_EXPRs. It may also be NULL, in which case operand 2 890 must not be NULL. 891 Operand 2 is either NULL_TREE or a TREE_VEC of the CASE_LABEL_EXPRs 892 of all the cases. */ 893DEFTREECODE (SWITCH_EXPR, "switch_expr", tcc_statement, 3) 894 895/* Used to represent a case label. 896 897 Operand 0 is CASE_LOW. It may be NULL_TREE, in which case the label 898 is a 'default' label. 899 Operand 1 is CASE_HIGH. If it is NULL_TREE, the label is a simple 900 (one-value) case label. If it is non-NULL_TREE, the case is a range. 901 Operand 2 is CASE_LABEL, which is is the corresponding LABEL_DECL. 902 Operand 4 is CASE_CHAIN. This operand is only used in tree-cfg.c to 903 speed up the lookup of case labels which use a particular edge in 904 the control flow graph. */ 905DEFTREECODE (CASE_LABEL_EXPR, "case_label_expr", tcc_statement, 4) 906 907/* Used to represent an inline assembly statement. ASM_STRING returns a 908 STRING_CST for the instruction (e.g., "mov x, y"). ASM_OUTPUTS, 909 ASM_INPUTS, and ASM_CLOBBERS represent the outputs, inputs, and clobbers 910 for the statement. ASM_LABELS, if present, indicates various destinations 911 for the asm; labels cannot be combined with outputs. */ 912DEFTREECODE (ASM_EXPR, "asm_expr", tcc_statement, 5) 913 914/* Variable references for SSA analysis. New SSA names are created every 915 time a variable is assigned a new value. The SSA builder uses SSA_NAME 916 nodes to implement SSA versioning. */ 917DEFTREECODE (SSA_NAME, "ssa_name", tcc_exceptional, 0) 918 919/* Used to represent a typed exception handler. CATCH_TYPES is the type (or 920 list of types) handled, and CATCH_BODY is the code for the handler. */ 921DEFTREECODE (CATCH_EXPR, "catch_expr", tcc_statement, 2) 922 923/* Used to represent an exception specification. EH_FILTER_TYPES is a list 924 of allowed types, and EH_FILTER_FAILURE is an expression to evaluate on 925 failure. */ 926DEFTREECODE (EH_FILTER_EXPR, "eh_filter_expr", tcc_statement, 2) 927 928/* Node used for describing a property that is known at compile 929 time. */ 930DEFTREECODE (SCEV_KNOWN, "scev_known", tcc_expression, 0) 931 932/* Node used for describing a property that is not known at compile 933 time. */ 934DEFTREECODE (SCEV_NOT_KNOWN, "scev_not_known", tcc_expression, 0) 935 936/* Polynomial chains of recurrences. 937 Under the form: cr = {CHREC_LEFT (cr), +, CHREC_RIGHT (cr)}. */ 938DEFTREECODE (POLYNOMIAL_CHREC, "polynomial_chrec", tcc_expression, 3) 939 940/* Used to chain children of container statements together. 941 Use the interface in tree-iterator.h to access this node. */ 942DEFTREECODE (STATEMENT_LIST, "statement_list", tcc_exceptional, 0) 943 944/* Predicate assertion. Artificial expression generated by the optimizers 945 to keep track of predicate values. This expression may only appear on 946 the RHS of assignments. 947 948 Given X = ASSERT_EXPR <Y, EXPR>, the optimizers can infer 949 two things: 950 951 1- X is a copy of Y. 952 2- EXPR is a conditional expression and is known to be true. 953 954 Valid and to be expected forms of conditional expressions are 955 valid GIMPLE conditional expressions (as defined by is_gimple_condexpr) 956 and conditional expressions with the first operand being a 957 PLUS_EXPR with a variable possibly wrapped in a NOP_EXPR first 958 operand and an integer constant second operand. 959 960 The type of the expression is the same as Y. */ 961DEFTREECODE (ASSERT_EXPR, "assert_expr", tcc_expression, 2) 962 963/* Base class information. Holds information about a class as a 964 baseclass of itself or another class. */ 965DEFTREECODE (TREE_BINFO, "tree_binfo", tcc_exceptional, 0) 966 967/* Records the size for an expression of variable size type. This is 968 for use in contexts in which we are accessing the entire object, 969 such as for a function call, or block copy. 970 Operand 0 is the real expression. 971 Operand 1 is the size of the type in the expression. */ 972DEFTREECODE (WITH_SIZE_EXPR, "with_size_expr", tcc_expression, 2) 973 974/* Extract elements from two input vectors Operand 0 and Operand 1 975 size VS, according to the offset OFF defined by Operand 2 as 976 follows: 977 If OFF > 0, the last VS - OFF elements of vector OP0 are concatenated to 978 the first OFF elements of the vector OP1. 979 If OFF == 0, then the returned vector is OP1. 980 On different targets OFF may take different forms; It can be an address, in 981 which case its low log2(VS)-1 bits define the offset, or it can be a mask 982 generated by the builtin targetm.vectorize.mask_for_load_builtin_decl. */ 983DEFTREECODE (REALIGN_LOAD_EXPR, "realign_load", tcc_expression, 3) 984 985/* Low-level memory addressing. Operands are BASE (address of static or 986 global variable or register), OFFSET (integer constant), 987 INDEX (register), STEP (integer constant), INDEX2 (register), 988 The corresponding address is BASE + STEP * INDEX + INDEX2 + OFFSET. 989 Only variations and values valid on the target are allowed. 990 991 The type of STEP, INDEX and INDEX2 is sizetype. 992 993 The type of BASE is a pointer type. If BASE is not an address of 994 a static or global variable INDEX2 will be NULL. 995 996 The type of OFFSET is a pointer type and determines TBAA the same as 997 the constant offset operand in MEM_REF. */ 998 999DEFTREECODE (TARGET_MEM_REF, "target_mem_ref", tcc_reference, 5) 1000 1001/* Memory addressing. Operands are a pointer and a tree constant integer 1002 byte offset of the pointer type that when dereferenced yields the 1003 type of the base object the pointer points into and which is used for 1004 TBAA purposes. 1005 The type of the MEM_REF is the type the bytes at the memory location 1006 are interpreted as. 1007 MEM_REF <p, c> is equivalent to ((typeof(c))p)->x... where x... is a 1008 chain of component references offsetting p by c. */ 1009DEFTREECODE (MEM_REF, "mem_ref", tcc_reference, 2) 1010 1011/* The ordering of the codes between OMP_PARALLEL and OMP_CRITICAL is 1012 exposed to TREE_RANGE_CHECK. */ 1013/* OpenMP - #pragma omp parallel [clause1 ... clauseN] 1014 Operand 0: OMP_PARALLEL_BODY: Code to be executed by all threads. 1015 Operand 1: OMP_PARALLEL_CLAUSES: List of clauses. */ 1016 1017DEFTREECODE (OMP_PARALLEL, "omp_parallel", tcc_statement, 2) 1018 1019/* OpenMP - #pragma omp task [clause1 ... clauseN] 1020 Operand 0: OMP_TASK_BODY: Code to be executed by all threads. 1021 Operand 1: OMP_TASK_CLAUSES: List of clauses. */ 1022 1023DEFTREECODE (OMP_TASK, "omp_task", tcc_statement, 2) 1024 1025/* OpenMP - #pragma omp for [clause1 ... clauseN] 1026 Operand 0: OMP_FOR_BODY: Loop body. 1027 Operand 1: OMP_FOR_CLAUSES: List of clauses. 1028 Operand 2: OMP_FOR_INIT: Initialization code of the form 1029 VAR = N1. 1030 Operand 3: OMP_FOR_COND: Loop conditional expression of the form 1031 VAR { <, >, <=, >= } N2. 1032 Operand 4: OMP_FOR_INCR: Loop index increment of the form 1033 VAR { +=, -= } INCR. 1034 Operand 5: OMP_FOR_PRE_BODY: Filled by the gimplifier with things 1035 from INIT, COND, and INCR that are technically part of the 1036 OMP_FOR structured block, but are evaluated before the loop 1037 body begins. 1038 1039 VAR must be an integer or pointer variable, which is implicitly thread 1040 private. N1, N2 and INCR are required to be loop invariant integer 1041 expressions that are evaluated without any synchronization. 1042 The evaluation order, frequency of evaluation and side-effects are 1043 unspecified by the standard. */ 1044DEFTREECODE (OMP_FOR, "omp_for", tcc_statement, 6) 1045 1046/* OpenMP - #pragma omp simd [clause1 ... clauseN] 1047 Operands like for OMP_FOR. */ 1048DEFTREECODE (OMP_SIMD, "omp_simd", tcc_statement, 6) 1049 1050/* Cilk Plus - #pragma simd [clause1 ... clauseN] 1051 Operands like for OMP_FOR. */ 1052DEFTREECODE (CILK_SIMD, "cilk_simd", tcc_statement, 6) 1053 1054/* OpenMP - #pragma omp distribute [clause1 ... clauseN] 1055 Operands like for OMP_FOR. */ 1056DEFTREECODE (OMP_DISTRIBUTE, "omp_distribute", tcc_statement, 6) 1057 1058/* OpenMP - #pragma omp teams [clause1 ... clauseN] 1059 Operand 0: OMP_TEAMS_BODY: Teams body. 1060 Operand 1: OMP_TEAMS_CLAUSES: List of clauses. */ 1061DEFTREECODE (OMP_TEAMS, "omp_teams", tcc_statement, 2) 1062 1063/* OpenMP - #pragma omp target data [clause1 ... clauseN] 1064 Operand 0: OMP_TARGET_DATA_BODY: Target data construct body. 1065 Operand 1: OMP_TARGET_DATA_CLAUSES: List of clauses. */ 1066DEFTREECODE (OMP_TARGET_DATA, "omp_target_data", tcc_statement, 2) 1067 1068/* OpenMP - #pragma omp target [clause1 ... clauseN] 1069 Operand 0: OMP_TARGET_BODY: Target construct body. 1070 Operand 1: OMP_TARGET_CLAUSES: List of clauses. */ 1071DEFTREECODE (OMP_TARGET, "omp_target", tcc_statement, 2) 1072 1073/* OpenMP - #pragma omp sections [clause1 ... clauseN] 1074 Operand 0: OMP_SECTIONS_BODY: Sections body. 1075 Operand 1: OMP_SECTIONS_CLAUSES: List of clauses. */ 1076DEFTREECODE (OMP_SECTIONS, "omp_sections", tcc_statement, 2) 1077 1078/* OpenMP - #pragma omp single 1079 Operand 0: OMP_SINGLE_BODY: Single section body. 1080 Operand 1: OMP_SINGLE_CLAUSES: List of clauses. */ 1081DEFTREECODE (OMP_SINGLE, "omp_single", tcc_statement, 2) 1082 1083/* OpenMP - #pragma omp section 1084 Operand 0: OMP_SECTION_BODY: Section body. */ 1085DEFTREECODE (OMP_SECTION, "omp_section", tcc_statement, 1) 1086 1087/* OpenMP - #pragma omp master 1088 Operand 0: OMP_MASTER_BODY: Master section body. */ 1089DEFTREECODE (OMP_MASTER, "omp_master", tcc_statement, 1) 1090 1091/* OpenMP - #pragma omp taskgroup 1092 Operand 0: OMP_TASKGROUP_BODY: Taskgroup body. */ 1093DEFTREECODE (OMP_TASKGROUP, "omp_taskgroup", tcc_statement, 1) 1094 1095/* OpenMP - #pragma omp ordered 1096 Operand 0: OMP_ORDERED_BODY: Master section body. */ 1097DEFTREECODE (OMP_ORDERED, "omp_ordered", tcc_statement, 1) 1098 1099/* OpenMP - #pragma omp critical [name] 1100 Operand 0: OMP_CRITICAL_BODY: Critical section body. 1101 Operand 1: OMP_CRITICAL_NAME: Identifier for critical section. */ 1102DEFTREECODE (OMP_CRITICAL, "omp_critical", tcc_statement, 2) 1103 1104/* OpenMP - #pragma omp target update [clause1 ... clauseN] 1105 Operand 0: OMP_TARGET_UPDATE_CLAUSES: List of clauses. */ 1106DEFTREECODE (OMP_TARGET_UPDATE, "omp_target_update", tcc_statement, 1) 1107 1108/* OMP_ATOMIC through OMP_ATOMIC_CAPTURE_NEW must be consecutive, 1109 or OMP_ATOMIC_SEQ_CST needs adjusting. */ 1110 1111/* OpenMP - #pragma omp atomic 1112 Operand 0: The address at which the atomic operation is to be performed. 1113 This address should be stabilized with save_expr. 1114 Operand 1: The expression to evaluate. When the old value of the object 1115 at the address is used in the expression, it should appear as if 1116 build_fold_indirect_ref of the address. */ 1117DEFTREECODE (OMP_ATOMIC, "omp_atomic", tcc_statement, 2) 1118 1119/* OpenMP - #pragma omp atomic read 1120 Operand 0: The address at which the atomic operation is to be performed. 1121 This address should be stabilized with save_expr. */ 1122DEFTREECODE (OMP_ATOMIC_READ, "omp_atomic_read", tcc_statement, 1) 1123 1124/* OpenMP - #pragma omp atomic capture 1125 Operand 0: The address at which the atomic operation is to be performed. 1126 This address should be stabilized with save_expr. 1127 Operand 1: The expression to evaluate. When the old value of the object 1128 at the address is used in the expression, it should appear as if 1129 build_fold_indirect_ref of the address. 1130 OMP_ATOMIC_CAPTURE_OLD returns the old memory content, 1131 OMP_ATOMIC_CAPTURE_NEW the new value. */ 1132DEFTREECODE (OMP_ATOMIC_CAPTURE_OLD, "omp_atomic_capture_old", tcc_statement, 2) 1133DEFTREECODE (OMP_ATOMIC_CAPTURE_NEW, "omp_atomic_capture_new", tcc_statement, 2) 1134 1135/* OpenMP clauses. */ 1136DEFTREECODE (OMP_CLAUSE, "omp_clause", tcc_exceptional, 0) 1137 1138/* TRANSACTION_EXPR tree code. 1139 Operand 0: BODY: contains body of the transaction. */ 1140DEFTREECODE (TRANSACTION_EXPR, "transaction_expr", tcc_expression, 1) 1141 1142/* Reduction operations. 1143 Operations that take a vector of elements and "reduce" it to a scalar 1144 result (e.g. summing the elements of the vector, finding the minimum over 1145 the vector elements, etc). 1146 Operand 0 is a vector. 1147 The expression returns a vector of the same type, with the first 1148 element in the vector holding the result of the reduction of all elements 1149 of the operand. The content of the other elements in the returned vector 1150 is undefined. */ 1151DEFTREECODE (REDUC_MAX_EXPR, "reduc_max_expr", tcc_unary, 1) 1152DEFTREECODE (REDUC_MIN_EXPR, "reduc_min_expr", tcc_unary, 1) 1153DEFTREECODE (REDUC_PLUS_EXPR, "reduc_plus_expr", tcc_unary, 1) 1154 1155/* Widening dot-product. 1156 The first two arguments are of type t1. 1157 The third argument and the result are of type t2, such that t2 is at least 1158 twice the size of t1. DOT_PROD_EXPR(arg1,arg2,arg3) is equivalent to: 1159 tmp = WIDEN_MULT_EXPR(arg1, arg2); 1160 arg3 = PLUS_EXPR (tmp, arg3); 1161 or: 1162 tmp = WIDEN_MULT_EXPR(arg1, arg2); 1163 arg3 = WIDEN_SUM_EXPR (tmp, arg3); */ 1164DEFTREECODE (DOT_PROD_EXPR, "dot_prod_expr", tcc_expression, 3) 1165 1166/* Widening summation. 1167 The first argument is of type t1. 1168 The second argument is of type t2, such that t2 is at least twice 1169 the size of t1. The type of the entire expression is also t2. 1170 WIDEN_SUM_EXPR is equivalent to first widening (promoting) 1171 the first argument from type t1 to type t2, and then summing it 1172 with the second argument. */ 1173DEFTREECODE (WIDEN_SUM_EXPR, "widen_sum_expr", tcc_binary, 2) 1174 1175/* Widening multiplication. 1176 The two arguments are of type t1. 1177 The result is of type t2, such that t2 is at least twice 1178 the size of t1. WIDEN_MULT_EXPR is equivalent to first widening (promoting) 1179 the arguments from type t1 to type t2, and then multiplying them. */ 1180DEFTREECODE (WIDEN_MULT_EXPR, "widen_mult_expr", tcc_binary, 2) 1181 1182/* Widening multiply-accumulate. 1183 The first two arguments are of type t1. 1184 The third argument and the result are of type t2, such as t2 is at least 1185 twice the size of t1. t1 and t2 must be integral or fixed-point types. 1186 The expression is equivalent to a WIDEN_MULT_EXPR operation 1187 of the first two operands followed by an add or subtract of the third 1188 operand. */ 1189DEFTREECODE (WIDEN_MULT_PLUS_EXPR, "widen_mult_plus_expr", tcc_expression, 3) 1190/* This is like the above, except in the final expression the multiply result 1191 is subtracted from t3. */ 1192DEFTREECODE (WIDEN_MULT_MINUS_EXPR, "widen_mult_minus_expr", tcc_expression, 3) 1193 1194/* Widening shift left. 1195 The first operand is of type t1. 1196 The second operand is the number of bits to shift by; it need not be the 1197 same type as the first operand and result. 1198 Note that the result is undefined if the second operand is larger 1199 than or equal to the first operand's type size. 1200 The type of the entire expression is t2, such that t2 is at least twice 1201 the size of t1. 1202 WIDEN_LSHIFT_EXPR is equivalent to first widening (promoting) 1203 the first argument from type t1 to type t2, and then shifting it 1204 by the second argument. */ 1205DEFTREECODE (WIDEN_LSHIFT_EXPR, "widen_lshift_expr", tcc_binary, 2) 1206 1207/* Fused multiply-add. 1208 All operands and the result are of the same type. No intermediate 1209 rounding is performed after multiplying operand one with operand two 1210 before adding operand three. */ 1211DEFTREECODE (FMA_EXPR, "fma_expr", tcc_expression, 3) 1212 1213/* Whole vector left/right shift in bits. 1214 Operand 0 is a vector to be shifted. 1215 Operand 1 is an integer shift amount in bits. */ 1216DEFTREECODE (VEC_LSHIFT_EXPR, "vec_lshift_expr", tcc_binary, 2) 1217DEFTREECODE (VEC_RSHIFT_EXPR, "vec_rshift_expr", tcc_binary, 2) 1218 1219/* Widening vector multiplication. 1220 The two operands are vectors with N elements of size S. Multiplying the 1221 elements of the two vectors will result in N products of size 2*S. 1222 VEC_WIDEN_MULT_HI_EXPR computes the N/2 high products. 1223 VEC_WIDEN_MULT_LO_EXPR computes the N/2 low products. */ 1224DEFTREECODE (VEC_WIDEN_MULT_HI_EXPR, "widen_mult_hi_expr", tcc_binary, 2) 1225DEFTREECODE (VEC_WIDEN_MULT_LO_EXPR, "widen_mult_lo_expr", tcc_binary, 2) 1226 1227/* Similarly, but return the even or odd N/2 products. */ 1228DEFTREECODE (VEC_WIDEN_MULT_EVEN_EXPR, "widen_mult_even_expr", tcc_binary, 2) 1229DEFTREECODE (VEC_WIDEN_MULT_ODD_EXPR, "widen_mult_odd_expr", tcc_binary, 2) 1230 1231/* Unpack (extract and promote/widen) the high/low elements of the input 1232 vector into the output vector. The input vector has twice as many 1233 elements as the output vector, that are half the size of the elements 1234 of the output vector. This is used to support type promotion. */ 1235DEFTREECODE (VEC_UNPACK_HI_EXPR, "vec_unpack_hi_expr", tcc_unary, 1) 1236DEFTREECODE (VEC_UNPACK_LO_EXPR, "vec_unpack_lo_expr", tcc_unary, 1) 1237 1238/* Unpack (extract) the high/low elements of the input vector, convert 1239 fixed point values to floating point and widen elements into the 1240 output vector. The input vector has twice as many elements as the output 1241 vector, that are half the size of the elements of the output vector. */ 1242DEFTREECODE (VEC_UNPACK_FLOAT_HI_EXPR, "vec_unpack_float_hi_expr", tcc_unary, 1) 1243DEFTREECODE (VEC_UNPACK_FLOAT_LO_EXPR, "vec_unpack_float_lo_expr", tcc_unary, 1) 1244 1245/* Pack (demote/narrow and merge) the elements of the two input vectors 1246 into the output vector using truncation/saturation. 1247 The elements of the input vectors are twice the size of the elements of the 1248 output vector. This is used to support type demotion. */ 1249DEFTREECODE (VEC_PACK_TRUNC_EXPR, "vec_pack_trunc_expr", tcc_binary, 2) 1250DEFTREECODE (VEC_PACK_SAT_EXPR, "vec_pack_sat_expr", tcc_binary, 2) 1251 1252/* Convert floating point values of the two input vectors to integer 1253 and pack (narrow and merge) the elements into the output vector. The 1254 elements of the input vector are twice the size of the elements of 1255 the output vector. */ 1256DEFTREECODE (VEC_PACK_FIX_TRUNC_EXPR, "vec_pack_fix_trunc_expr", tcc_binary, 2) 1257 1258/* Widening vector shift left in bits. 1259 Operand 0 is a vector to be shifted with N elements of size S. 1260 Operand 1 is an integer shift amount in bits. 1261 The result of the operation is N elements of size 2*S. 1262 VEC_WIDEN_LSHIFT_HI_EXPR computes the N/2 high results. 1263 VEC_WIDEN_LSHIFT_LO_EXPR computes the N/2 low results. 1264 */ 1265DEFTREECODE (VEC_WIDEN_LSHIFT_HI_EXPR, "widen_lshift_hi_expr", tcc_binary, 2) 1266DEFTREECODE (VEC_WIDEN_LSHIFT_LO_EXPR, "widen_lshift_lo_expr", tcc_binary, 2) 1267 1268/* PREDICT_EXPR. Specify hint for branch prediction. The 1269 PREDICT_EXPR_PREDICTOR specify predictor and PREDICT_EXPR_OUTCOME the 1270 outcome (0 for not taken and 1 for taken). Once the profile is guessed 1271 all conditional branches leading to execution paths executing the 1272 PREDICT_EXPR will get predicted by the specified predictor. */ 1273DEFTREECODE (PREDICT_EXPR, "predict_expr", tcc_expression, 1) 1274 1275/* OPTIMIZATION_NODE. Node to store the optimization options. */ 1276DEFTREECODE (OPTIMIZATION_NODE, "optimization_node", tcc_exceptional, 0) 1277 1278/* TARGET_OPTION_NODE. Node to store the target specific options. */ 1279DEFTREECODE (TARGET_OPTION_NODE, "target_option_node", tcc_exceptional, 0) 1280 1281/* ANNOTATE_EXPR. 1282 Operand 0 is the expression to be annotated. 1283 Operand 1 is the annotation id. */ 1284DEFTREECODE (ANNOTATE_EXPR, "annotate_expr", tcc_expression, 2) 1285 1286/* Cilk spawn statement 1287 Operand 0 is the CALL_EXPR. */ 1288DEFTREECODE (CILK_SPAWN_STMT, "cilk_spawn_stmt", tcc_statement, 1) 1289 1290/* Cilk Sync statement: Does not have any operands. */ 1291DEFTREECODE (CILK_SYNC_STMT, "cilk_sync_stmt", tcc_statement, 0) 1292 1293/* 1294Local variables: 1295mode:c 1296End: 1297*/ 1298