1/* This file contains the definitions and documentation for the 2 tree codes used in GCC. 3 Copyright (C) 1987, 1988, 1993, 1995, 1997, 1998, 2000, 2001, 2004, 2005, 4 2006 Free Software Foundation, Inc. 5 6This file is part of GCC. 7 8GCC is free software; you can redistribute it and/or modify it under 9the terms of the GNU General Public License as published by the Free 10Software Foundation; either version 2, or (at your option) any later 11version. 12 13GCC is distributed in the hope that it will be useful, but WITHOUT ANY 14WARRANTY; without even the implied warranty of MERCHANTABILITY or 15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 16for more details. 17 18You should have received a copy of the GNU General Public License 19along with GCC; see the file COPYING. If not, write to the Free 20Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 2102110-1301, USA. */ 22 23 24/* For tcc_references, tcc_expression, tcc_comparison, tcc_unary, 25 tcc_binary, and tcc_statement nodes, which use struct tree_exp, the 26 4th element is the number of argument slots to allocate. This 27 determines the size of the tree node object. Other nodes use 28 different structures, and the size is determined by the tree_union 29 member structure; the 4th element should be zero. Languages that 30 define language-specific tcc_exceptional or tcc_constant codes must 31 define the tree_size langhook to say how big they are. 32 33 These tree codes have been sorted so that the macros in tree.h that 34 check for various tree codes are optimized into range checks. This 35 gives a measurable performance improvement. When adding a new 36 code, consider its placement in relation to the other codes. */ 37 38/* Any erroneous construct is parsed into a node of this type. 39 This type of node is accepted without complaint in all contexts 40 by later parsing activities, to avoid multiple error messages 41 for one error. 42 No fields in these nodes are used except the TREE_CODE. */ 43DEFTREECODE (ERROR_MARK, "error_mark", tcc_exceptional, 0) 44 45/* Used to represent a name (such as, in the DECL_NAME of a decl node). 46 Internally it looks like a STRING_CST node. 47 There is only one IDENTIFIER_NODE ever made for any particular name. 48 Use `get_identifier' to get it (or create it, the first time). */ 49DEFTREECODE (IDENTIFIER_NODE, "identifier_node", tcc_exceptional, 0) 50 51/* Has the TREE_VALUE and TREE_PURPOSE fields. */ 52/* These nodes are made into lists by chaining through the 53 TREE_CHAIN field. The elements of the list live in the 54 TREE_VALUE fields, while TREE_PURPOSE fields are occasionally 55 used as well to get the effect of Lisp association lists. */ 56DEFTREECODE (TREE_LIST, "tree_list", tcc_exceptional, 0) 57 58/* These nodes contain an array of tree nodes. */ 59DEFTREECODE (TREE_VEC, "tree_vec", tcc_exceptional, 0) 60 61/* A symbol binding block. These are arranged in a tree, 62 where the BLOCK_SUBBLOCKS field contains a chain of subblocks 63 chained through the BLOCK_CHAIN field. 64 BLOCK_SUPERCONTEXT points to the parent block. 65 For a block which represents the outermost scope of a function, it 66 points to the FUNCTION_DECL node. 67 BLOCK_VARS points to a chain of decl nodes. 68 BLOCK_CHAIN points to the next BLOCK at the same level. 69 BLOCK_ABSTRACT_ORIGIN points to the original (abstract) tree node which 70 this block is an instance of, or else is NULL to indicate that this 71 block is not an instance of anything else. When non-NULL, the value 72 could either point to another BLOCK node or it could point to a 73 FUNCTION_DECL node (e.g. in the case of a block representing the 74 outermost scope of a particular inlining of a function). 75 BLOCK_ABSTRACT is nonzero if the block represents an abstract 76 instance of a block (i.e. one which is nested within an abstract 77 instance of an inline function). 78 TREE_ASM_WRITTEN is nonzero if the block was actually referenced 79 in the generated assembly. */ 80DEFTREECODE (BLOCK, "block", tcc_exceptional, 0) 81 82/* Each data type is represented by a tree node whose code is one of 83 the following: */ 84/* Each node that represents a data type has a component TYPE_SIZE 85 containing a tree that is an expression for the size in bits. 86 The TYPE_MODE contains the machine mode for values of this type. 87 The TYPE_POINTER_TO field contains a type for a pointer to this type, 88 or zero if no such has been created yet. 89 The TYPE_NEXT_VARIANT field is used to chain together types 90 that are variants made by type modifiers such as "const" and "volatile". 91 The TYPE_MAIN_VARIANT field, in any member of such a chain, 92 points to the start of the chain. 93 The TYPE_NONCOPIED_PARTS field is a list specifying which parts 94 of an object of this type should *not* be copied by assignment. 95 The TREE_VALUE of each is a FIELD_DECL that should not be 96 copied. The TREE_PURPOSE is an initial value for that field when 97 an object of this type is initialized via an INIT_EXPR. It may 98 be NULL if no special value is required. Even the things in this 99 list are copied if the right-hand side of an assignment is known 100 to be a complete object (rather than being, perhaps, a subobject 101 of some other object.) The determination of what constitutes a 102 complete object is done by fixed_type_p. 103 The TYPE_NAME field contains info on the name used in the program 104 for this type (for GDB symbol table output). It is either a 105 TYPE_DECL node, for types that are typedefs, or an IDENTIFIER_NODE 106 in the case of structs, unions or enums that are known with a tag, 107 or zero for types that have no special name. 108 The TYPE_CONTEXT for any sort of type which could have a name or 109 which could have named members (e.g. tagged types in C/C++) will 110 point to the node which represents the scope of the given type, or 111 will be NULL_TREE if the type has "file scope". For most types, this 112 will point to a BLOCK node or a FUNCTION_DECL node, but it could also 113 point to a FUNCTION_TYPE node (for types whose scope is limited to the 114 formal parameter list of some function type specification) or it 115 could point to a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE node 116 (for C++ "member" types). 117 For non-tagged-types, TYPE_CONTEXT need not be set to anything in 118 particular, since any type which is of some type category (e.g. 119 an array type or a function type) which cannot either have a name 120 itself or have named members doesn't really have a "scope" per se. 121 The TREE_CHAIN field is used as a forward-references to names for 122 ENUMERAL_TYPE, RECORD_TYPE, UNION_TYPE, and QUAL_UNION_TYPE nodes; 123 see below. */ 124 125/* The ordering of the following codes is optimized for the checking 126 macros in tree.h. Changing the order will degrade the speed of the 127 compiler. OFFSET_TYPE, ENUMERAL_TYPE, BOOLEAN_TYPE, INTEGER_TYPE, 128 REAL_TYPE, POINTER_TYPE. */ 129 130/* An offset is a pointer relative to an object. 131 The TREE_TYPE field is the type of the object at the offset. 132 The TYPE_OFFSET_BASETYPE points to the node for the type of object 133 that the offset is relative to. */ 134DEFTREECODE (OFFSET_TYPE, "offset_type", tcc_type, 0) 135 136/* C enums. The type node looks just like an INTEGER_TYPE node. 137 The symbols for the values of the enum type are defined by 138 CONST_DECL nodes, but the type does not point to them; 139 however, the TYPE_VALUES is a list in which each element's TREE_PURPOSE 140 is a name and the TREE_VALUE is the value (an INTEGER_CST node). */ 141/* A forward reference `enum foo' when no enum named foo is defined yet 142 has zero (a null pointer) in its TYPE_SIZE. The tag name is in 143 the TYPE_NAME field. If the type is later defined, the normal 144 fields are filled in. 145 RECORD_TYPE, UNION_TYPE, and QUAL_UNION_TYPE forward refs are 146 treated similarly. */ 147DEFTREECODE (ENUMERAL_TYPE, "enumeral_type", tcc_type, 0) 148 149/* Boolean type (true or false are the only values). Looks like an 150 INTEGRAL_TYPE. */ 151DEFTREECODE (BOOLEAN_TYPE, "boolean_type", tcc_type, 0) 152 153/* Integer types in all languages, including char in C. 154 Also used for sub-ranges of other discrete types. 155 Has components TYPE_MIN_VALUE, TYPE_MAX_VALUE (expressions, inclusive) 156 and TYPE_PRECISION (number of bits used by this type). 157 In the case of a subrange type in Pascal, the TREE_TYPE 158 of this will point at the supertype (another INTEGER_TYPE, 159 or an ENUMERAL_TYPE or BOOLEAN_TYPE). 160 Otherwise, the TREE_TYPE is zero. */ 161DEFTREECODE (INTEGER_TYPE, "integer_type", tcc_type, 0) 162 163/* C's float and double. Different floating types are distinguished 164 by machine mode and by the TYPE_SIZE and the TYPE_PRECISION. */ 165DEFTREECODE (REAL_TYPE, "real_type", tcc_type, 0) 166 167/* The ordering of the following codes is optimized for the checking 168 macros in tree.h. Changing the order will degrade the speed of the 169 compiler. POINTER_TYPE, REFERENCE_TYPE. Note that this range 170 overlaps the previous range of ordered types. */ 171 172/* All pointer-to-x types have code POINTER_TYPE. 173 The TREE_TYPE points to the node for the type pointed to. */ 174DEFTREECODE (POINTER_TYPE, "pointer_type", tcc_type, 0) 175 176/* A reference is like a pointer except that it is coerced 177 automatically to the value it points to. Used in C++. */ 178DEFTREECODE (REFERENCE_TYPE, "reference_type", tcc_type, 0) 179 180/* APPLE LOCAL begin radar 5732232 - blocks */ 181/* All pointer-to-block types have code BLOCK_POINTER_TYPE. 182 The TREE_TYPE points to the node for the type pointed to. */ 183DEFTREECODE (BLOCK_POINTER_TYPE, "block_pointer_type", tcc_type, 0) 184/* APPLE LOCAL end radar 5732232 - blocks */ 185/* The ordering of the following codes is optimized for the checking 186 macros in tree.h. Changing the order will degrade the speed of the 187 compiler. COMPLEX_TYPE, VECTOR_TYPE, ARRAY_TYPE. */ 188 189/* Complex number types. The TREE_TYPE field is the data type 190 of the real and imaginary parts. */ 191DEFTREECODE (COMPLEX_TYPE, "complex_type", tcc_type, 0) 192 193/* Vector types. The TREE_TYPE field is the data type of the vector 194 elements. The TYPE_PRECISION field is the number of subparts of 195 the vector. */ 196DEFTREECODE (VECTOR_TYPE, "vector_type", tcc_type, 0) 197 198/* The ordering of the following codes is optimized for the checking 199 macros in tree.h. Changing the order will degrade the speed of the 200 compiler. ARRAY_TYPE, RECORD_TYPE, UNION_TYPE, QUAL_UNION_TYPE. 201 Note that this range overlaps the previous range. */ 202 203/* Types of arrays. Special fields: 204 TREE_TYPE Type of an array element. 205 TYPE_DOMAIN Type to index by. 206 Its range of values specifies the array length. 207 The field TYPE_POINTER_TO (TREE_TYPE (array_type)) is always nonzero 208 and holds the type to coerce a value of that array type to in C. 209 TYPE_STRING_FLAG indicates a string (in contrast to an array of chars) 210 in languages (such as Chill) that make a distinction. */ 211/* Array types in C or Pascal */ 212DEFTREECODE (ARRAY_TYPE, "array_type", tcc_type, 0) 213 214/* Struct in C, or record in Pascal. */ 215/* Special fields: 216 TYPE_FIELDS chain of FIELD_DECLs for the fields of the struct, 217 and VAR_DECLs, TYPE_DECLs and CONST_DECLs for record-scope variables, 218 types and enumerators. 219 A few may need to be added for Pascal. */ 220/* See the comment above, before ENUMERAL_TYPE, for how 221 forward references to struct tags are handled in C. */ 222DEFTREECODE (RECORD_TYPE, "record_type", tcc_type, 0) 223 224/* Union in C. Like a struct, except that the offsets of the fields 225 will all be zero. */ 226/* See the comment above, before ENUMERAL_TYPE, for how 227 forward references to union tags are handled in C. */ 228DEFTREECODE (UNION_TYPE, "union_type", tcc_type, 0) /* C union type */ 229 230/* Similar to UNION_TYPE, except that the expressions in DECL_QUALIFIER 231 in each FIELD_DECL determine what the union contains. The first 232 field whose DECL_QUALIFIER expression is true is deemed to occupy 233 the union. */ 234DEFTREECODE (QUAL_UNION_TYPE, "qual_union_type", tcc_type, 0) 235 236/* The ordering of the following codes is optimized for the checking 237 macros in tree.h. Changing the order will degrade the speed of the 238 compiler. VOID_TYPE, FUNCTION_TYPE, METHOD_TYPE. */ 239 240/* The void type in C */ 241DEFTREECODE (VOID_TYPE, "void_type", tcc_type, 0) 242 243/* Type of functions. Special fields: 244 TREE_TYPE type of value returned. 245 TYPE_ARG_TYPES list of types of arguments expected. 246 this list is made of TREE_LIST nodes. 247 Types of "Procedures" in languages where they are different from functions 248 have code FUNCTION_TYPE also, but then TREE_TYPE is zero or void type. */ 249DEFTREECODE (FUNCTION_TYPE, "function_type", tcc_type, 0) 250 251/* METHOD_TYPE is the type of a function which takes an extra first 252 argument for "self", which is not present in the declared argument list. 253 The TREE_TYPE is the return type of the method. The TYPE_METHOD_BASETYPE 254 is the type of "self". TYPE_ARG_TYPES is the real argument list, which 255 includes the hidden argument for "self". */ 256DEFTREECODE (METHOD_TYPE, "method_type", tcc_type, 0) 257 258/* This is a language-specific kind of type. 259 Its meaning is defined by the language front end. 260 layout_type does not know how to lay this out, 261 so the front-end must do so manually. */ 262DEFTREECODE (LANG_TYPE, "lang_type", tcc_type, 0) 263 264/* Expressions */ 265 266/* First, the constants. */ 267 268/* Contents are in TREE_INT_CST_LOW and TREE_INT_CST_HIGH fields, 269 32 bits each, giving us a 64 bit constant capability. INTEGER_CST 270 nodes can be shared, and therefore should be considered read only. 271 They should be copied, before setting a flag such as 272 TREE_OVERFLOW. If an INTEGER_CST has TREE_OVERFLOW or 273 TREE_CONSTANT_OVERFLOW already set, it is known to be unique. 274 INTEGER_CST nodes are created for the integral types, for pointer 275 types and for vector and float types in some circumstances. */ 276DEFTREECODE (INTEGER_CST, "integer_cst", tcc_constant, 0) 277 278/* Contents are in TREE_REAL_CST field. */ 279DEFTREECODE (REAL_CST, "real_cst", tcc_constant, 0) 280 281/* Contents are in TREE_REALPART and TREE_IMAGPART fields, 282 whose contents are other constant nodes. */ 283DEFTREECODE (COMPLEX_CST, "complex_cst", tcc_constant, 0) 284 285/* Contents are in TREE_VECTOR_CST_ELTS field. */ 286DEFTREECODE (VECTOR_CST, "vector_cst", tcc_constant, 0) 287 288/* Contents are TREE_STRING_LENGTH and the actual contents of the string. */ 289DEFTREECODE (STRING_CST, "string_cst", tcc_constant, 0) 290 291/* Declarations. All references to names are represented as ..._DECL 292 nodes. The decls in one binding context are chained through the 293 TREE_CHAIN field. Each DECL has a DECL_NAME field which contains 294 an IDENTIFIER_NODE. (Some decls, most often labels, may have zero 295 as the DECL_NAME). DECL_CONTEXT points to the node representing 296 the context in which this declaration has its scope. For 297 FIELD_DECLs, this is the RECORD_TYPE, UNION_TYPE, or 298 QUAL_UNION_TYPE node that the field is a member of. For VAR_DECL, 299 PARM_DECL, FUNCTION_DECL, LABEL_DECL, and CONST_DECL nodes, this 300 points to either the FUNCTION_DECL for the containing function, the 301 RECORD_TYPE or UNION_TYPE for the containing type, or NULL_TREE or 302 a TRANSLATION_UNIT_DECL if the given decl has "file scope". 303 DECL_ABSTRACT_ORIGIN, if non-NULL, points to the original (abstract) 304 ..._DECL node of which this decl is an (inlined or template expanded) 305 instance. 306 The TREE_TYPE field holds the data type of the object, when relevant. 307 LABEL_DECLs have no data type. For TYPE_DECL, the TREE_TYPE field 308 contents are the type whose name is being declared. 309 The DECL_ALIGN, DECL_SIZE, 310 and DECL_MODE fields exist in decl nodes just as in type nodes. 311 They are unused in LABEL_DECL, TYPE_DECL and CONST_DECL nodes. 312 313 DECL_FIELD_BIT_OFFSET holds an integer number of bits offset for 314 the location. DECL_VOFFSET holds an expression for a variable 315 offset; it is to be multiplied by DECL_VOFFSET_UNIT (an integer). 316 These fields are relevant only in FIELD_DECLs and PARM_DECLs. 317 318 DECL_INITIAL holds the value to initialize a variable to, 319 or the value of a constant. For a function, it holds the body 320 (a node of type BLOCK representing the function's binding contour 321 and whose body contains the function's statements.) For a LABEL_DECL 322 in C, it is a flag, nonzero if the label's definition has been seen. 323 324 PARM_DECLs use a special field: 325 DECL_ARG_TYPE is the type in which the argument is actually 326 passed, which may be different from its type within the function. 327 328 FUNCTION_DECLs use four special fields: 329 DECL_ARGUMENTS holds a chain of PARM_DECL nodes for the arguments. 330 DECL_RESULT holds a RESULT_DECL node for the value of a function. 331 The DECL_RTL field is 0 for a function that returns no value. 332 (C functions returning void have zero here.) 333 The TREE_TYPE field is the type in which the result is actually 334 returned. This is usually the same as the return type of the 335 FUNCTION_DECL, but it may be a wider integer type because of 336 promotion. 337 DECL_FUNCTION_CODE is a code number that is nonzero for 338 built-in functions. Its value is an enum built_in_function 339 that says which built-in function it is. 340 341 DECL_SOURCE_FILE holds a filename string and DECL_SOURCE_LINE 342 holds a line number. In some cases these can be the location of 343 a reference, if no definition has been seen. 344 345 DECL_ABSTRACT is nonzero if the decl represents an abstract instance 346 of a decl (i.e. one which is nested within an abstract instance of a 347 inline function. */ 348 349DEFTREECODE (FUNCTION_DECL, "function_decl", tcc_declaration, 0) 350DEFTREECODE (LABEL_DECL, "label_decl", tcc_declaration, 0) 351/* The ordering of the following codes is optimized for the checking 352 macros in tree.h. Changing the order will degrade the speed of the 353 compiler. FIELD_DECL, VAR_DECL, CONST_DECL, PARM_DECL, 354 TYPE_DECL. */ 355DEFTREECODE (FIELD_DECL, "field_decl", tcc_declaration, 0) 356DEFTREECODE (VAR_DECL, "var_decl", tcc_declaration, 0) 357DEFTREECODE (CONST_DECL, "const_decl", tcc_declaration, 0) 358DEFTREECODE (PARM_DECL, "parm_decl", tcc_declaration, 0) 359DEFTREECODE (TYPE_DECL, "type_decl", tcc_declaration, 0) 360DEFTREECODE (RESULT_DECL, "result_decl", tcc_declaration, 0) 361 362/* Memory tags used in tree-ssa to represent memory locations in 363 virtual SSA. */ 364DEFTREECODE (STRUCT_FIELD_TAG, "struct_field_tag", tcc_declaration, 0) 365DEFTREECODE (NAME_MEMORY_TAG, "name_memory_tag", tcc_declaration, 0) 366DEFTREECODE (SYMBOL_MEMORY_TAG, "symbol_memory_tag", tcc_declaration, 0) 367 368/* A namespace declaration. Namespaces appear in DECL_CONTEXT of other 369 _DECLs, providing a hierarchy of names. */ 370DEFTREECODE (NAMESPACE_DECL, "namespace_decl", tcc_declaration, 0) 371 372/* A translation unit. This is not technically a declaration, since it 373 can't be looked up, but it's close enough. */ 374DEFTREECODE (TRANSLATION_UNIT_DECL, "translation_unit_decl",\ 375 tcc_declaration, 0) 376 377/* References to storage. */ 378 379/* Value is structure or union component. 380 Operand 0 is the structure or union (an expression). 381 Operand 1 is the field (a node of type FIELD_DECL). 382 Operand 2, if present, is the value of DECL_FIELD_OFFSET, measured 383 in units of DECL_OFFSET_ALIGN / BITS_PER_UNIT. */ 384DEFTREECODE (COMPONENT_REF, "component_ref", tcc_reference, 3) 385 386/* Reference to a group of bits within an object. Similar to COMPONENT_REF 387 except the position is given explicitly rather than via a FIELD_DECL. 388 Operand 0 is the structure or union expression; 389 operand 1 is a tree giving the number of bits being referenced; 390 operand 2 is a tree giving the position of the first referenced bit. 391 The field can be either a signed or unsigned field; 392 BIT_FIELD_REF_UNSIGNED says which. */ 393DEFTREECODE (BIT_FIELD_REF, "bit_field_ref", tcc_reference, 3) 394 395/* The ordering of the following codes is optimized for the checking 396 macros in tree.h. Changing the order will degrade the speed of the 397 compiler. INDIRECT_REF, ALIGN_INDIRECT_REF, MISALIGNED_INDIRECT_REF. */ 398 399/* C unary `*' or Pascal `^'. One operand, an expression for a pointer. */ 400DEFTREECODE (INDIRECT_REF, "indirect_ref", tcc_reference, 1) 401 402/* Like above, but aligns the referenced address (i.e, if the address 403 in P is not aligned on TYPE_ALIGN boundary, then &(*P) != P). */ 404DEFTREECODE (ALIGN_INDIRECT_REF, "align_indirect_ref", tcc_reference, 1) 405 406/* Same as INDIRECT_REF, but also specifies the alignment of the referenced 407 address: 408 Operand 0 is the referenced address (a pointer); 409 Operand 1 is an INTEGER_CST which represents the alignment of the address, 410 or 0 if the alignment is unknown. */ 411DEFTREECODE (MISALIGNED_INDIRECT_REF, "misaligned_indirect_ref", tcc_reference, 2) 412 413/* Array indexing. 414 Operand 0 is the array; operand 1 is a (single) array index. 415 Operand 2, if present, is a copy of TYPE_MIN_VALUE of the index. 416 Operand 3, if present, is the element size, measured in units of 417 the alignment of the element type. */ 418DEFTREECODE (ARRAY_REF, "array_ref", tcc_reference, 4) 419 420/* Likewise, except that the result is a range ("slice") of the array. The 421 starting index of the resulting array is taken from operand 1 and the size 422 of the range is taken from the type of the expression. */ 423DEFTREECODE (ARRAY_RANGE_REF, "array_range_ref", tcc_reference, 4) 424 425/* Used to represent lookup of runtime type dependent data. Often this is 426 a reference to a vtable, but it needn't be. Operands are: 427 OBJ_TYPE_REF_EXPR: An expression that evaluates the value to use. 428 OBJ_TYPE_REF_OBJECT: Is the object on whose behalf the lookup is 429 being performed. Through this the optimizers may be able to statically 430 determine the dynamic type of the object. 431 OBJ_TYPE_REF_TOKEN: Something front-end specific used to resolve the 432 reference to something simpler, usually to the address of a DECL. 433 Never touched by the middle-end. Good choices would be either an 434 identifier or a vtable index. */ 435DEFTREECODE (OBJ_TYPE_REF, "obj_type_ref", tcc_expression, 3) 436 437/* The exception object from the runtime. */ 438DEFTREECODE (EXC_PTR_EXPR, "exc_ptr_expr", tcc_expression, 0) 439 440/* The filter object from the runtime. */ 441DEFTREECODE (FILTER_EXPR, "filter_expr", tcc_expression, 0) 442 443/* Constructor: return an aggregate value made from specified components. 444 In C, this is used only for structure and array initializers. 445 The operand is a sequence of component values made out of a VEC of 446 struct constructor_elt. 447 448 For ARRAY_TYPE: 449 The field INDEX of each constructor_elt is the corresponding index. 450 If the index is a RANGE_EXPR, it is a short-hand for many nodes, 451 one for each index in the range. (If the corresponding field VALUE 452 has side-effects, they are evaluated once for each element. Wrap the 453 value in a SAVE_EXPR if you want to evaluate side effects only once.) 454 455 For RECORD_TYPE, UNION_TYPE, or QUAL_UNION_TYPE: 456 The field INDEX of each node is a FIELD_DECL. */ 457DEFTREECODE (CONSTRUCTOR, "constructor", tcc_exceptional, 0) 458 459/* The expression types are mostly straightforward, with the fourth argument 460 of DEFTREECODE saying how many operands there are. 461 Unless otherwise specified, the operands are expressions and the 462 types of all the operands and the expression must all be the same. */ 463 464/* Contains two expressions to compute, one followed by the other. 465 the first value is ignored. The second one's value is used. The 466 type of the first expression need not agree with the other types. */ 467DEFTREECODE (COMPOUND_EXPR, "compound_expr", tcc_expression, 2) 468 469/* Assignment expression. Operand 0 is the what to set; 1, the new value. */ 470DEFTREECODE (MODIFY_EXPR, "modify_expr", tcc_expression, 2) 471 472/* Initialization expression. Operand 0 is the variable to initialize; 473 Operand 1 is the initializer. This differs from MODIFY_EXPR in that any 474 reference to the referent of operand 0 within operand 1 is undefined. */ 475DEFTREECODE (INIT_EXPR, "init_expr", tcc_expression, 2) 476 477/* For TARGET_EXPR, operand 0 is the target of an initialization, 478 operand 1 is the initializer for the target, which may be void 479 if simply expanding it initializes the target. 480 operand 2 is the cleanup for this node, if any. 481 operand 3 is the saved initializer after this node has been 482 expanded once; this is so we can re-expand the tree later. */ 483DEFTREECODE (TARGET_EXPR, "target_expr", tcc_expression, 4) 484 485/* Conditional expression ( ... ? ... : ... in C). 486 Operand 0 is the condition. 487 Operand 1 is the then-value. 488 Operand 2 is the else-value. 489 Operand 0 may be of any type. 490 Operand 1 must have the same type as the entire expression, unless 491 it unconditionally throws an exception, in which case it should 492 have VOID_TYPE. The same constraints apply to operand 2. */ 493DEFTREECODE (COND_EXPR, "cond_expr", tcc_expression, 3) 494 495/* Vector conditional expression. It is like COND_EXPR, but with 496 vector operands. 497 498 A = VEC_COND_EXPR ( X < Y, B, C) 499 500 means 501 502 for (i=0; i<N; i++) 503 A[i] = X[i] < Y[i] ? B[i] : C[i]; 504*/ 505DEFTREECODE (VEC_COND_EXPR, "vec_cond_expr", tcc_expression, 3) 506 507/* Declare local variables, including making RTL and allocating space. 508 BIND_EXPR_VARS is a chain of VAR_DECL nodes for the variables. 509 BIND_EXPR_BODY is the body, the expression to be computed using 510 the variables. The value of operand 1 becomes that of the BIND_EXPR. 511 BIND_EXPR_BLOCK is the BLOCK that corresponds to these bindings 512 for debugging purposes. If this BIND_EXPR is actually expanded, 513 that sets the TREE_USED flag in the BLOCK. 514 515 The BIND_EXPR is not responsible for informing parsers 516 about these variables. If the body is coming from the input file, 517 then the code that creates the BIND_EXPR is also responsible for 518 informing the parser of the variables. 519 520 If the BIND_EXPR is ever expanded, its TREE_USED flag is set. 521 This tells the code for debugging symbol tables not to ignore the BIND_EXPR. 522 If the BIND_EXPR should be output for debugging but will not be expanded, 523 set the TREE_USED flag by hand. 524 525 In order for the BIND_EXPR to be known at all, the code that creates it 526 must also install it as a subblock in the tree of BLOCK 527 nodes for the function. */ 528DEFTREECODE (BIND_EXPR, "bind_expr", tcc_expression, 3) 529 530/* Function call. Operand 0 is the function. 531 Operand 1 is the argument list, a list of expressions 532 made out of a chain of TREE_LIST nodes. 533 Operand 2 is the static chain argument, or NULL. */ 534DEFTREECODE (CALL_EXPR, "call_expr", tcc_expression, 3) 535 536/* Specify a value to compute along with its corresponding cleanup. 537 Operand 0 is the cleanup expression. 538 The cleanup is executed by the first enclosing CLEANUP_POINT_EXPR, 539 which must exist. This differs from TRY_CATCH_EXPR in that operand 1 540 is always evaluated when cleanups are run. */ 541DEFTREECODE (WITH_CLEANUP_EXPR, "with_cleanup_expr", tcc_expression, 1) 542 543/* Specify a cleanup point. 544 Operand 0 is an expression that may have cleanups. If it does, those 545 cleanups are executed after the expression is expanded. 546 547 Note that if the expression is a reference to storage, it is forced out 548 of memory before the cleanups are run. This is necessary to handle 549 cases where the cleanups modify the storage referenced; in the 550 expression 't.i', if 't' is a struct with an integer member 'i' and a 551 cleanup which modifies 'i', the value of the expression depends on 552 whether the cleanup is run before or after 't.i' is evaluated. When 553 expand_expr is run on 't.i', it returns a MEM. This is not good enough; 554 the value of 't.i' must be forced out of memory. 555 556 As a consequence, the operand of a CLEANUP_POINT_EXPR must not have 557 BLKmode, because it will not be forced out of memory. */ 558DEFTREECODE (CLEANUP_POINT_EXPR, "cleanup_point_expr", tcc_expression, 1) 559 560/* The following two codes are used in languages that have types where 561 some field in an object of the type contains a value that is used in 562 the computation of another field's offset or size and/or the size of 563 the type. The positions and/or sizes of fields can vary from object 564 to object of the same type or even for one and the same object within 565 its scope. 566 567 Record types with discriminants in Ada or schema types in Pascal are 568 examples of such types. This mechanism is also used to create "fat 569 pointers" for unconstrained array types in Ada; the fat pointer is a 570 structure one of whose fields is a pointer to the actual array type 571 and the other field is a pointer to a template, which is a structure 572 containing the bounds of the array. The bounds in the type pointed 573 to by the first field in the fat pointer refer to the values in the 574 template. 575 576 When you wish to construct such a type you need "self-references" 577 that allow you to reference the object having this type from the 578 TYPE node, i.e. without having a variable instantiating this type. 579 580 Such a "self-references" is done using a PLACEHOLDER_EXPR. This is 581 a node that will later be replaced with the object being referenced. 582 Its type is that of the object and selects which object to use from 583 a chain of references (see below). No other slots are used in the 584 PLACEHOLDER_EXPR. 585 586 For example, if your type FOO is a RECORD_TYPE with a field BAR, 587 and you need the value of <variable>.BAR to calculate TYPE_SIZE 588 (FOO), just substitute <variable> above with a PLACEHOLDER_EXPR 589 whose TREE_TYPE is FOO. Then construct your COMPONENT_REF with 590 the PLACEHOLDER_EXPR as the first operand (which has the correct 591 type). Later, when the size is needed in the program, the back-end 592 will find this PLACEHOLDER_EXPR and generate code to calculate the 593 actual size at run-time. In the following, we describe how this 594 calculation is done. 595 596 When we wish to evaluate a size or offset, we check whether it contains a 597 PLACEHOLDER_EXPR. If it does, we call substitute_placeholder_in_expr 598 passing both that tree and an expression within which the object may be 599 found. The latter expression is the object itself in the simple case of 600 an Ada record with discriminant, but it can be the array in the case of an 601 unconstrained array. 602 603 In the latter case, we need the fat pointer, because the bounds of 604 the array can only be accessed from it. However, we rely here on the 605 fact that the expression for the array contains the dereference of 606 the fat pointer that obtained the array pointer. */ 607 608/* Denotes a record to later be substituted before evaluating this expression. 609 The type of this expression is used to find the record to replace it. */ 610DEFTREECODE (PLACEHOLDER_EXPR, "placeholder_expr", tcc_exceptional, 0) 611 612/* Simple arithmetic. */ 613DEFTREECODE (PLUS_EXPR, "plus_expr", tcc_binary, 2) 614DEFTREECODE (MINUS_EXPR, "minus_expr", tcc_binary, 2) 615DEFTREECODE (MULT_EXPR, "mult_expr", tcc_binary, 2) 616 617/* Division for integer result that rounds the quotient toward zero. */ 618DEFTREECODE (TRUNC_DIV_EXPR, "trunc_div_expr", tcc_binary, 2) 619 620/* Division for integer result that rounds the quotient toward infinity. */ 621DEFTREECODE (CEIL_DIV_EXPR, "ceil_div_expr", tcc_binary, 2) 622 623/* Division for integer result that rounds toward minus infinity. */ 624DEFTREECODE (FLOOR_DIV_EXPR, "floor_div_expr", tcc_binary, 2) 625 626/* Division for integer result that rounds toward nearest integer. */ 627DEFTREECODE (ROUND_DIV_EXPR, "round_div_expr", tcc_binary, 2) 628 629/* Four kinds of remainder that go with the four kinds of division. */ 630DEFTREECODE (TRUNC_MOD_EXPR, "trunc_mod_expr", tcc_binary, 2) 631DEFTREECODE (CEIL_MOD_EXPR, "ceil_mod_expr", tcc_binary, 2) 632DEFTREECODE (FLOOR_MOD_EXPR, "floor_mod_expr", tcc_binary, 2) 633DEFTREECODE (ROUND_MOD_EXPR, "round_mod_expr", tcc_binary, 2) 634 635/* Division for real result. */ 636DEFTREECODE (RDIV_EXPR, "rdiv_expr", tcc_binary, 2) 637 638/* Division which is not supposed to need rounding. 639 Used for pointer subtraction in C. */ 640DEFTREECODE (EXACT_DIV_EXPR, "exact_div_expr", tcc_binary, 2) 641 642/* Conversion of real to fixed point: four ways to round, 643 like the four ways to divide. 644 CONVERT_EXPR can also be used to convert a real to an integer, 645 and that is what is used in languages that do not have ways of 646 specifying which of these is wanted. Maybe these are not needed. */ 647DEFTREECODE (FIX_TRUNC_EXPR, "fix_trunc_expr", tcc_unary, 1) 648DEFTREECODE (FIX_CEIL_EXPR, "fix_ceil_expr", tcc_unary, 1) 649DEFTREECODE (FIX_FLOOR_EXPR, "fix_floor_expr", tcc_unary, 1) 650DEFTREECODE (FIX_ROUND_EXPR, "fix_round_expr", tcc_unary, 1) 651 652/* Conversion of an integer to a real. */ 653DEFTREECODE (FLOAT_EXPR, "float_expr", tcc_unary, 1) 654 655/* Unary negation. */ 656DEFTREECODE (NEGATE_EXPR, "negate_expr", tcc_unary, 1) 657 658/* Minimum and maximum values. When used with floating point, if both 659 operands are zeros, or if either operand is NaN, then it is unspecified 660 which of the two operands is returned as the result. */ 661DEFTREECODE (MIN_EXPR, "min_expr", tcc_binary, 2) 662DEFTREECODE (MAX_EXPR, "max_expr", tcc_binary, 2) 663 664/* Represents the absolute value of the operand. 665 666 An ABS_EXPR must have either an INTEGER_TYPE or a REAL_TYPE. The 667 operand of the ABS_EXPR must have the same type. */ 668DEFTREECODE (ABS_EXPR, "abs_expr", tcc_unary, 1) 669 670/* Shift operations for shift and rotate. 671 Shift means logical shift if done on an 672 unsigned type, arithmetic shift if done on a signed type. 673 The second operand is the number of bits to 674 shift by; it need not be the same type as the first operand and result. 675 Note that the result is undefined if the second operand is larger 676 than or equal to the first operand's type size. */ 677DEFTREECODE (LSHIFT_EXPR, "lshift_expr", tcc_binary, 2) 678DEFTREECODE (RSHIFT_EXPR, "rshift_expr", tcc_binary, 2) 679DEFTREECODE (LROTATE_EXPR, "lrotate_expr", tcc_binary, 2) 680DEFTREECODE (RROTATE_EXPR, "rrotate_expr", tcc_binary, 2) 681 682/* Bitwise operations. Operands have same mode as result. */ 683DEFTREECODE (BIT_IOR_EXPR, "bit_ior_expr", tcc_binary, 2) 684DEFTREECODE (BIT_XOR_EXPR, "bit_xor_expr", tcc_binary, 2) 685DEFTREECODE (BIT_AND_EXPR, "bit_and_expr", tcc_binary, 2) 686DEFTREECODE (BIT_NOT_EXPR, "bit_not_expr", tcc_unary, 1) 687 688/* ANDIF and ORIF allow the second operand not to be computed if the 689 value of the expression is determined from the first operand. AND, 690 OR, and XOR always compute the second operand whether its value is 691 needed or not (for side effects). The operand may have 692 BOOLEAN_TYPE or INTEGER_TYPE. In either case, the argument will be 693 either zero or one. For example, a TRUTH_NOT_EXPR will never have 694 an INTEGER_TYPE VAR_DECL as its argument; instead, a NE_EXPR will be 695 used to compare the VAR_DECL to zero, thereby obtaining a node with 696 value zero or one. */ 697DEFTREECODE (TRUTH_ANDIF_EXPR, "truth_andif_expr", tcc_expression, 2) 698DEFTREECODE (TRUTH_ORIF_EXPR, "truth_orif_expr", tcc_expression, 2) 699DEFTREECODE (TRUTH_AND_EXPR, "truth_and_expr", tcc_expression, 2) 700DEFTREECODE (TRUTH_OR_EXPR, "truth_or_expr", tcc_expression, 2) 701DEFTREECODE (TRUTH_XOR_EXPR, "truth_xor_expr", tcc_expression, 2) 702DEFTREECODE (TRUTH_NOT_EXPR, "truth_not_expr", tcc_expression, 1) 703 704/* Relational operators. 705 `EQ_EXPR' and `NE_EXPR' are allowed for any types. 706 The others are allowed only for integer (or pointer or enumeral) 707 or real types. 708 In all cases the operands will have the same type, 709 and the value is always the type used by the language for booleans. */ 710DEFTREECODE (LT_EXPR, "lt_expr", tcc_comparison, 2) 711DEFTREECODE (LE_EXPR, "le_expr", tcc_comparison, 2) 712DEFTREECODE (GT_EXPR, "gt_expr", tcc_comparison, 2) 713DEFTREECODE (GE_EXPR, "ge_expr", tcc_comparison, 2) 714DEFTREECODE (EQ_EXPR, "eq_expr", tcc_comparison, 2) 715DEFTREECODE (NE_EXPR, "ne_expr", tcc_comparison, 2) 716 717/* Additional relational operators for floating point unordered. */ 718DEFTREECODE (UNORDERED_EXPR, "unordered_expr", tcc_comparison, 2) 719DEFTREECODE (ORDERED_EXPR, "ordered_expr", tcc_comparison, 2) 720 721/* These are equivalent to unordered or ... */ 722DEFTREECODE (UNLT_EXPR, "unlt_expr", tcc_comparison, 2) 723DEFTREECODE (UNLE_EXPR, "unle_expr", tcc_comparison, 2) 724DEFTREECODE (UNGT_EXPR, "ungt_expr", tcc_comparison, 2) 725DEFTREECODE (UNGE_EXPR, "unge_expr", tcc_comparison, 2) 726DEFTREECODE (UNEQ_EXPR, "uneq_expr", tcc_comparison, 2) 727 728/* This is the reverse of uneq_expr. */ 729DEFTREECODE (LTGT_EXPR, "ltgt_expr", tcc_comparison, 2) 730 731DEFTREECODE (RANGE_EXPR, "range_expr", tcc_binary, 2) 732 733/* Represents a conversion of type of a value. 734 All conversions, including implicit ones, must be 735 represented by CONVERT_EXPR or NOP_EXPR nodes. */ 736DEFTREECODE (CONVERT_EXPR, "convert_expr", tcc_unary, 1) 737 738/* Represents a conversion expected to require no code to be generated. */ 739DEFTREECODE (NOP_EXPR, "nop_expr", tcc_unary, 1) 740 741/* Value is same as argument, but guaranteed not an lvalue. */ 742DEFTREECODE (NON_LVALUE_EXPR, "non_lvalue_expr", tcc_unary, 1) 743 744/* Represents viewing something of one type as being of a second type. 745 This corresponds to an "Unchecked Conversion" in Ada and roughly to 746 the idiom *(type2 *)&X in C. The only operand is the value to be 747 viewed as being of another type. It is undefined if the type of the 748 input and of the expression have different sizes. 749 750 This code may also be used within the LHS of a MODIFY_EXPR, in which 751 case no actual data motion may occur. TREE_ADDRESSABLE will be set in 752 this case and GCC must abort if it could not do the operation without 753 generating insns. */ 754DEFTREECODE (VIEW_CONVERT_EXPR, "view_convert_expr", tcc_reference, 1) 755 756/* Represents something we computed once and will use multiple times. 757 First operand is that expression. After it is evaluated once, it 758 will be replaced by the temporary variable that holds the value. */ 759DEFTREECODE (SAVE_EXPR, "save_expr", tcc_expression, 1) 760 761/* & in C. Value is the address at which the operand's value resides. 762 Operand may have any mode. Result mode is Pmode. */ 763DEFTREECODE (ADDR_EXPR, "addr_expr", tcc_expression, 1) 764 765/* Operand0 is a function constant; result is part N of a function 766 descriptor of type ptr_mode. */ 767DEFTREECODE (FDESC_EXPR, "fdesc_expr", tcc_expression, 2) 768 769/* Given two real or integer operands of the same type, 770 returns a complex value of the corresponding complex type. */ 771DEFTREECODE (COMPLEX_EXPR, "complex_expr", tcc_binary, 2) 772 773/* Complex conjugate of operand. Used only on complex types. */ 774DEFTREECODE (CONJ_EXPR, "conj_expr", tcc_unary, 1) 775 776/* Used only on an operand of complex type, these return 777 a value of the corresponding component type. */ 778DEFTREECODE (REALPART_EXPR, "realpart_expr", tcc_reference, 1) 779DEFTREECODE (IMAGPART_EXPR, "imagpart_expr", tcc_reference, 1) 780 781/* Nodes for ++ and -- in C. 782 The second arg is how much to increment or decrement by. 783 For a pointer, it would be the size of the object pointed to. */ 784DEFTREECODE (PREDECREMENT_EXPR, "predecrement_expr", tcc_expression, 2) 785DEFTREECODE (PREINCREMENT_EXPR, "preincrement_expr", tcc_expression, 2) 786DEFTREECODE (POSTDECREMENT_EXPR, "postdecrement_expr", tcc_expression, 2) 787DEFTREECODE (POSTINCREMENT_EXPR, "postincrement_expr", tcc_expression, 2) 788 789/* Used to implement `va_arg'. */ 790DEFTREECODE (VA_ARG_EXPR, "va_arg_expr", tcc_expression, 1) 791 792/* Evaluate operand 1. If and only if an exception is thrown during 793 the evaluation of operand 1, evaluate operand 2. 794 795 This differs from TRY_FINALLY_EXPR in that operand 2 is not evaluated 796 on a normal or jump exit, only on an exception. */ 797DEFTREECODE (TRY_CATCH_EXPR, "try_catch_expr", tcc_statement, 2) 798 799/* Evaluate the first operand. 800 The second operand is a cleanup expression which is evaluated 801 on any exit (normal, exception, or jump out) from this expression. */ 802DEFTREECODE (TRY_FINALLY_EXPR, "try_finally", tcc_statement, 2) 803 804/* These types of expressions have no useful value, 805 and always have side effects. */ 806 807/* Used to represent a local declaration. The operand is DECL_EXPR_DECL. */ 808DEFTREECODE (DECL_EXPR, "decl_expr", tcc_statement, 1) 809 810/* A label definition, encapsulated as a statement. 811 Operand 0 is the LABEL_DECL node for the label that appears here. 812 The type should be void and the value should be ignored. */ 813DEFTREECODE (LABEL_EXPR, "label_expr", tcc_statement, 1) 814 815/* GOTO. Operand 0 is a LABEL_DECL node or an expression. 816 The type should be void and the value should be ignored. */ 817DEFTREECODE (GOTO_EXPR, "goto_expr", tcc_statement, 1) 818 819/* RETURN. Evaluates operand 0, then returns from the current function. 820 Presumably that operand is an assignment that stores into the 821 RESULT_DECL that hold the value to be returned. 822 The operand may be null. 823 The type should be void and the value should be ignored. */ 824DEFTREECODE (RETURN_EXPR, "return_expr", tcc_statement, 1) 825 826/* Exit the inner most loop conditionally. Operand 0 is the condition. 827 The type should be void and the value should be ignored. */ 828DEFTREECODE (EXIT_EXPR, "exit_expr", tcc_statement, 1) 829 830/* A loop. Operand 0 is the body of the loop. 831 It must contain an EXIT_EXPR or is an infinite loop. 832 The type should be void and the value should be ignored. */ 833DEFTREECODE (LOOP_EXPR, "loop_expr", tcc_statement, 1) 834 835/* Switch expression. 836 837 TREE_TYPE is the original type of the condition, before any 838 language required type conversions. It may be NULL, in which case 839 the original type and final types are assumed to be the same. 840 841 Operand 0 is the expression used to perform the branch, 842 Operand 1 is the body of the switch, which probably contains 843 CASE_LABEL_EXPRs. It may also be NULL, in which case operand 2 844 must not be NULL. 845 Operand 2 is either NULL_TREE or a TREE_VEC of the CASE_LABEL_EXPRs 846 of all the cases. */ 847DEFTREECODE (SWITCH_EXPR, "switch_expr", tcc_statement, 3) 848 849/* Used to represent a case label. The operands are CASE_LOW and 850 CASE_HIGH, respectively. If CASE_LOW is NULL_TREE, the label is a 851 'default' label. If CASE_HIGH is NULL_TREE, the label is a normal case 852 label. CASE_LABEL is the corresponding LABEL_DECL. */ 853DEFTREECODE (CASE_LABEL_EXPR, "case_label_expr", tcc_statement, 3) 854 855/* RESX. Resume execution after an exception. Operand 0 is a 856 number indicating the exception region that is being left. */ 857DEFTREECODE (RESX_EXPR, "resx_expr", tcc_statement, 1) 858 859/* Used to represent an inline assembly statement. ASM_STRING returns a 860 STRING_CST for the instruction (e.g., "mov x, y"). ASM_OUTPUTS, 861 ASM_INPUTS, and ASM_CLOBBERS represent the outputs, inputs, and clobbers 862 for the statement. */ 863DEFTREECODE (ASM_EXPR, "asm_expr", tcc_statement, 4) 864 865/* Variable references for SSA analysis. New SSA names are created every 866 time a variable is assigned a new value. The SSA builder uses SSA_NAME 867 nodes to implement SSA versioning. */ 868DEFTREECODE (SSA_NAME, "ssa_name", tcc_exceptional, 0) 869 870/* SSA PHI operator. PHI_RESULT is the new SSA_NAME node created by 871 the PHI node. PHI_ARG_LENGTH is the number of arguments. 872 PHI_ARG_ELT returns the Ith tuple <ssa_name, edge> from the 873 argument list. Each tuple contains the incoming reaching 874 definition (SSA_NAME node) and the edge via which that definition 875 is coming through. */ 876DEFTREECODE (PHI_NODE, "phi_node", tcc_exceptional, 0) 877 878/* Used to represent a typed exception handler. CATCH_TYPES is the type (or 879 list of types) handled, and CATCH_BODY is the code for the handler. */ 880DEFTREECODE (CATCH_EXPR, "catch_expr", tcc_statement, 2) 881 882/* Used to represent an exception specification. EH_FILTER_TYPES is a list 883 of allowed types, and EH_FILTER_FAILURE is an expression to evaluate on 884 failure. EH_FILTER_MUST_NOT_THROW controls which range type to use when 885 expanding. */ 886DEFTREECODE (EH_FILTER_EXPR, "eh_filter_expr", tcc_statement, 2) 887 888/* Node used for describing a property that is known at compile 889 time. */ 890DEFTREECODE (SCEV_KNOWN, "scev_known", tcc_expression, 0) 891 892/* Node used for describing a property that is not known at compile 893 time. */ 894DEFTREECODE (SCEV_NOT_KNOWN, "scev_not_known", tcc_expression, 0) 895 896/* Polynomial chains of recurrences. 897 Under the form: cr = {CHREC_LEFT (cr), +, CHREC_RIGHT (cr)}. */ 898DEFTREECODE (POLYNOMIAL_CHREC, "polynomial_chrec", tcc_expression, 3) 899 900/* Used to chain children of container statements together. 901 Use the interface in tree-iterator.h to access this node. */ 902DEFTREECODE (STATEMENT_LIST, "statement_list", tcc_exceptional, 0) 903 904/* Value handles. Artificial nodes to represent expressions in 905 partial redundancy elimination (tree-ssa-pre.c). These nodes are 906 used for expression canonicalization. If two expressions compute 907 the same value, they will be assigned the same value handle. */ 908DEFTREECODE (VALUE_HANDLE, "value_handle", tcc_exceptional, 0) 909 910/* Predicate assertion. Artificial expression generated by the optimizers 911 to keep track of predicate values. This expression may only appear on 912 the RHS of assignments. 913 914 Given X = ASSERT_EXPR <Y, EXPR>, the optimizers can infer 915 two things: 916 917 1- X is a copy of Y. 918 2- EXPR is a GIMPLE conditional expression (as defined by 919 is_gimple_condexpr) and is known to be true. 920 921 The type of the expression is the same as Y. */ 922DEFTREECODE (ASSERT_EXPR, "assert_expr", tcc_expression, 2) 923 924/* Base class information. Holds information about a class as a 925 baseclass of itself or another class. */ 926DEFTREECODE (TREE_BINFO, "tree_binfo", tcc_exceptional, 0) 927 928/* Records the size for an expression of variable size type. This is 929 for use in contexts in which we are accessing the entire object, 930 such as for a function call, or block copy. 931 Operand 0 is the real expression. 932 Operand 1 is the size of the type in the expression. */ 933DEFTREECODE (WITH_SIZE_EXPR, "with_size_expr", tcc_expression, 2) 934 935/* Extract elements from two input vectors Operand 0 and Operand 1 936 size VS, according to the offset OFF defined by Operand 2 as 937 follows: 938 If OFF > 0, the last VS - OFF elements of vector OP0 are concatenated to 939 the first OFF elements of the vector OP1. 940 If OFF == 0, then the returned vector is OP1. 941 On different targets OFF may take different forms; It can be an address, in 942 which case its low log2(VS)-1 bits define the offset, or it can be a mask 943 generated by the builtin targetm.vectorize.mask_for_load_builtin_decl. */ 944DEFTREECODE (REALIGN_LOAD_EXPR, "realign_load", tcc_expression, 3) 945 946/* Low-level memory addressing. Operands are SYMBOL (static or global 947 variable), BASE (register), INDEX (register), STEP (integer constant), 948 OFFSET (integer constant). Corresponding address is 949 SYMBOL + BASE + STEP * INDEX + OFFSET. Only variations and values valid on 950 the target are allowed. 951 952 The type of STEP, INDEX and OFFSET is sizetype. The type of BASE is 953 sizetype or a pointer type (if SYMBOL is NULL). 954 955 The sixth argument is the reference to the original memory access, which 956 is preserved for the purposes of the RTL alias analysis. The seventh 957 argument is a tag representing results of the tree level alias analysis. */ 958 959DEFTREECODE (TARGET_MEM_REF, "target_mem_ref", tcc_reference, 7) 960 961/* The ordering of the codes between OMP_PARALLEL and OMP_CRITICAL is 962 exposed to TREE_RANGE_CHECK. */ 963/* OpenMP - #pragma omp parallel [clause1 ... clauseN] 964 Operand 0: OMP_PARALLEL_BODY: Code to be executed by all threads. 965 Operand 1: OMP_PARALLEL_CLAUSES: List of clauses. 966 Operand 2: OMP_PARALLEL_FN: FUNCTION_DECL used when outlining the 967 body of the parallel region. Only valid after 968 pass_lower_omp. 969 Operand 3: OMP_PARALLEL_DATA_ARG: Local variable in the parent 970 function containing data to be shared with the child 971 function. */ 972 973DEFTREECODE (OMP_PARALLEL, "omp_parallel", tcc_statement, 4) 974 975/* OpenMP - #pragma omp for [clause1 ... clauseN] 976 Operand 0: OMP_FOR_BODY: Loop body. 977 Operand 1: OMP_FOR_CLAUSES: List of clauses. 978 Operand 2: OMP_FOR_INIT: Initialization code of the form 979 VAR = N1. 980 Operand 3: OMP_FOR_COND: Loop conditional expression of the form 981 VAR { <, >, <=, >= } N2. 982 Operand 4: OMP_FOR_INCR: Loop index increment of the form 983 VAR { +=, -= } INCR. 984 Operand 5: OMP_FOR_PRE_BODY: Filled by the gimplifier with things 985 from INIT, COND, and INCR that are technically part of the 986 OMP_FOR structured block, but are evaluated before the loop 987 body begins. 988 989 VAR must be a signed integer variable, which is implicitly thread 990 private. N1, N2 and INCR are required to be loop invariant integer 991 expressions that are evaluated without any synchronization. 992 The evaluation order, frequency of evaluation and side-effects are 993 unspecified by the standard. */ 994DEFTREECODE (OMP_FOR, "omp_for", tcc_statement, 6) 995 996/* OpenMP - #pragma omp sections [clause1 ... clauseN] 997 Operand 0: OMP_SECTIONS_BODY: Sections body. 998 Operand 1: OMP_SECTIONS_CLAUSES: List of clauses. */ 999DEFTREECODE (OMP_SECTIONS, "omp_sections", tcc_statement, 2) 1000 1001/* OpenMP - #pragma omp single 1002 Operand 0: OMP_SINGLE_BODY: Single section body. 1003 Operand 1: OMP_SINGLE_CLAUSES: List of clauses. */ 1004DEFTREECODE (OMP_SINGLE, "omp_single", tcc_statement, 2) 1005 1006/* OpenMP - #pragma omp section 1007 Operand 0: OMP_SECTION_BODY: Section body. */ 1008DEFTREECODE (OMP_SECTION, "omp_section", tcc_statement, 1) 1009 1010/* OpenMP - #pragma omp master 1011 Operand 0: OMP_MASTER_BODY: Master section body. */ 1012DEFTREECODE (OMP_MASTER, "omp_master", tcc_statement, 1) 1013 1014/* OpenMP - #pragma omp ordered 1015 Operand 0: OMP_ORDERED_BODY: Master section body. */ 1016DEFTREECODE (OMP_ORDERED, "omp_ordered", tcc_statement, 1) 1017 1018/* OpenMP - #pragma omp critical [name] 1019 Operand 0: OMP_CRITICAL_BODY: Critical section body. 1020 Operand 1: OMP_CRITICAL_NAME: Identifier for critical section. */ 1021DEFTREECODE (OMP_CRITICAL, "omp_critical", tcc_statement, 2) 1022 1023/* Return from an OpenMP directive. */ 1024DEFTREECODE (OMP_RETURN, "omp_return", tcc_statement, 0) 1025 1026/* OpenMP - An intermediate tree code to mark the location of the 1027 loop or sections iteration in the partially lowered code. */ 1028DEFTREECODE (OMP_CONTINUE, "omp_continue", tcc_statement, 0) 1029 1030/* OpenMP - #pragma omp atomic 1031 Operand 0: The address at which the atomic operation is to be performed. 1032 This address should be stabilized with save_expr. 1033 Operand 1: The expression to evaluate. When the old value of the object 1034 at the address is used in the expression, it should appear as if 1035 build_fold_indirect_ref of the address. */ 1036DEFTREECODE (OMP_ATOMIC, "omp_atomic", tcc_statement, 2) 1037 1038/* OpenMP clauses. */ 1039DEFTREECODE (OMP_CLAUSE, "omp_clause", tcc_exceptional, 0) 1040 1041/* Reduction operations. 1042 Operations that take a vector of elements and "reduce" it to a scalar 1043 result (e.g. summing the elements of the vector, finding the minimum over 1044 the vector elements, etc). 1045 Operand 0 is a vector; the first element in the vector has the result. 1046 Operand 1 is a vector. */ 1047DEFTREECODE (REDUC_MAX_EXPR, "reduc_max_expr", tcc_unary, 1) 1048DEFTREECODE (REDUC_MIN_EXPR, "reduc_min_expr", tcc_unary, 1) 1049DEFTREECODE (REDUC_PLUS_EXPR, "reduc_plus_expr", tcc_unary, 1) 1050 1051/* Widenning dot-product. 1052 The first two arguments are of type t1. 1053 The third argument and the result are of type t2, such that t2 is at least 1054 twice the size of t1. DOT_PROD_EXPR(arg1,arg2,arg3) is equivalent to: 1055 tmp = WIDEN_MULT_EXPR(arg1, arg2); 1056 arg3 = PLUS_EXPR (tmp, arg3); 1057 or: 1058 tmp = WIDEN_MULT_EXPR(arg1, arg2); 1059 arg3 = WIDEN_SUM_EXPR (tmp, arg3); */ 1060DEFTREECODE (DOT_PROD_EXPR, "dot_prod_expr", tcc_expression, 3) 1061 1062/* Widenning summation. 1063 The first argument is of type t1. 1064 The second argument is of type t2, such that t2 is at least twice 1065 the size of t1. The type of the entire expression is also t2. 1066 WIDEN_SUM_EXPR is equivalent to first widening (promoting) 1067 the first argument from type t1 to type t2, and then summing it 1068 with the second argument. */ 1069DEFTREECODE (WIDEN_SUM_EXPR, "widen_sum_expr", tcc_binary, 2) 1070 1071/* Widenning multiplication. 1072 The two arguments are of type t1. 1073 The result is of type t2, such that t2 is at least twice 1074 the size of t1. WIDEN_MULT_EXPR is equivalent to first widening (promoting) 1075 the arguments from type t1 to type t2, and then multiplying them. */ 1076DEFTREECODE (WIDEN_MULT_EXPR, "widen_mult_expr", tcc_binary, 2) 1077 1078/* Whole vector left/right shift in bits. 1079 Operand 0 is a vector to be shifted. 1080 Operand 1 is an integer shift amount in bits. */ 1081DEFTREECODE (VEC_LSHIFT_EXPR, "vec_lshift_expr", tcc_binary, 2) 1082DEFTREECODE (VEC_RSHIFT_EXPR, "vec_rshift_expr", tcc_binary, 2) 1083 1084/* 1085Local variables: 1086mode:c 1087End: 1088*/ 1089