1/* This file contains the definitions and documentation for the
2 tree codes used in GCC.
3 Copyright (C) 1987-2017 Free Software Foundation, Inc.
5This file is part of GCC.
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
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.
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/>. */
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.
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.
36 When adding a new tree code which might appear as GIMPLE_ASSIGN RHS
37 code, proper handler in chkp_compute_bounds_for_assignment may
38 be required. */
40/* Any erroneous construct is parsed into a node of this type.
41 This type of node is accepted without complaint in all contexts
42 by later parsing activities, to avoid multiple error messages
43 for one error.
44 No fields in these nodes are used except the TREE_CODE. */
45DEFTREECODE (ERROR_MARK, "error_mark", tcc_exceptional, 0)
47/* Used to represent a name (such as, in the DECL_NAME of a decl node).
48 Internally it looks like a STRING_CST node.
49 There is only one IDENTIFIER_NODE ever made for any particular name.
50 Use `get_identifier' to get it (or create it, the first time). */
51DEFTREECODE (IDENTIFIER_NODE, "identifier_node", tcc_exceptional, 0)
53/* Has the TREE_VALUE and TREE_PURPOSE fields. */
54/* These nodes are made into lists by chaining through the
55 TREE_CHAIN field. The elements of the list live in the
56 TREE_VALUE fields, while TREE_PURPOSE fields are occasionally
57 used as well to get the effect of Lisp association lists. */
58DEFTREECODE (TREE_LIST, "tree_list", tcc_exceptional, 0)
60/* These nodes contain an array of tree nodes. */
61DEFTREECODE (TREE_VEC, "tree_vec", tcc_exceptional, 0)
63/* A symbol binding block. These are arranged in a tree,
64 where the BLOCK_SUBBLOCKS field contains a chain of subblocks
65 chained through the BLOCK_CHAIN field.
66 BLOCK_SUPERCONTEXT points to the parent block.
67 For a block which represents the outermost scope of a function, it
68 points to the FUNCTION_DECL node.
69 BLOCK_VARS points to a chain of decl nodes.
70 BLOCK_CHAIN points to the next BLOCK at the same level.
71 BLOCK_ABSTRACT_ORIGIN points to the original (abstract) tree node which
72 this block is an instance of, or else is NULL to indicate that this
73 block is not an instance of anything else. When non-NULL, the value
74 could either point to another BLOCK node or it could point to a
75 FUNCTION_DECL node (e.g. in the case of a block representing the
76 outermost scope of a particular inlining of a function).
77 BLOCK_ABSTRACT is nonzero if the block represents an abstract
78 instance of a block (i.e. one which is nested within an abstract
79 instance of an inline function).
80 TREE_ASM_WRITTEN is nonzero if the block was actually referenced
81 in the generated assembly. */
82DEFTREECODE (BLOCK, "block", tcc_exceptional, 0)
84/* Each data type is represented by a tree node whose code is one of
85 the following: */
86/* Each node that represents a data type has a component TYPE_SIZE
87 containing a tree that is an expression for the size in bits.
88 The TYPE_MODE contains the machine mode for values of this type.
89 The TYPE_POINTER_TO field contains a type for a pointer to this type,
90 or zero if no such has been created yet.
91 The TYPE_NEXT_VARIANT field is used to chain together types
92 that are variants made by type modifiers such as "const" and "volatile".
93 The TYPE_MAIN_VARIANT field, in any member of such a chain,
94 points to the start of the chain.
95 The TYPE_NAME field contains info on the name used in the program
96 for this type (for GDB symbol table output). It is either a
97 TYPE_DECL node, for types that are typedefs, or an IDENTIFIER_NODE
98 in the case of structs, unions or enums that are known with a tag,
99 or zero for types that have no special name.
100 The TYPE_CONTEXT for any sort of type which could have a name or
101 which could have named members (e.g. tagged types in C/C++) will
102 point to the node which represents the scope of the given type, or
103 will be NULL_TREE if the type has "file scope". For most types, this
104 will point to a BLOCK node or a FUNCTION_DECL node, but it could also
105 point to a FUNCTION_TYPE node (for types whose scope is limited to the
106 formal parameter list of some function type specification) or it
107 could point to a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE node
108 (for C++ "member" types).
109 For non-tagged-types, TYPE_CONTEXT need not be set to anything in
110 particular, since any type which is of some type category (e.g.
111 an array type or a function type) which cannot either have a name
112 itself or have named members doesn't really have a "scope" per se.
113 The TYPE_STUB_DECL field is used as a forward-references to names for
115 see below. */
117/* The ordering of the following codes is optimized for the checking
118 macros in tree.h. Changing the order will degrade the speed of the
122/* An offset is a pointer relative to an object.
123 The TREE_TYPE field is the type of the object at the offset.
124 The TYPE_OFFSET_BASETYPE points to the node for the type of object
125 that the offset is relative to. */
126DEFTREECODE (OFFSET_TYPE, "offset_type", tcc_type, 0)
128/* C enums. The type node looks just like an INTEGER_TYPE node.
129 The symbols for the values of the enum type are defined by
130 CONST_DECL nodes, but the type does not point to them;
131 however, the TYPE_VALUES is a list in which each element's TREE_PURPOSE
132 is a name and the TREE_VALUE is the value (an INTEGER_CST node). */
133/* A forward reference `enum foo' when no enum named foo is defined yet
134 has zero (a null pointer) in its TYPE_SIZE. The tag name is in
135 the TYPE_NAME field. If the type is later defined, the normal
136 fields are filled in.
137 RECORD_TYPE, UNION_TYPE, and QUAL_UNION_TYPE forward refs are
138 treated similarly. */
139DEFTREECODE (ENUMERAL_TYPE, "enumeral_type", tcc_type, 0)
141/* Boolean type (true or false are the only values). Looks like an
143DEFTREECODE (BOOLEAN_TYPE, "boolean_type", tcc_type, 0)
145/* Integer types in all languages, including char in C.
146 Also used for sub-ranges of other discrete types.
147 Has components TYPE_MIN_VALUE, TYPE_MAX_VALUE (expressions, inclusive)
148 and TYPE_PRECISION (number of bits used by this type).
149 In the case of a subrange type in Pascal, the TREE_TYPE
150 of this will point at the supertype (another INTEGER_TYPE,
152 Otherwise, the TREE_TYPE is zero. */
153DEFTREECODE (INTEGER_TYPE, "integer_type", tcc_type, 0)
155/* C's float and double. Different floating types are distinguished
156 by machine mode and by the TYPE_SIZE and the TYPE_PRECISION. */
157DEFTREECODE (REAL_TYPE, "real_type", tcc_type, 0)
159/* The ordering of the following codes is optimized for the checking
160 macros in tree.h. Changing the order will degrade the speed of the
161 compiler. POINTER_TYPE, REFERENCE_TYPE. Note that this range
162 overlaps the previous range of ordered types. */
164/* All pointer-to-x types have code POINTER_TYPE.
165 The TREE_TYPE points to the node for the type pointed to. */
166DEFTREECODE (POINTER_TYPE, "pointer_type", tcc_type, 0)
168/* A reference is like a pointer except that it is coerced
169 automatically to the value it points to. Used in C++. */
170DEFTREECODE (REFERENCE_TYPE, "reference_type", tcc_type, 0)
172/* The C++ decltype(nullptr) type. */
173DEFTREECODE (NULLPTR_TYPE, "nullptr_type", tcc_type, 0)
175/* _Fract and _Accum types in Embedded-C. Different fixed-point types
176 are distinguished by machine mode and by the TYPE_SIZE and the
178DEFTREECODE (FIXED_POINT_TYPE, "fixed_point_type", tcc_type, 0)
180/* The ordering of the following codes is optimized for the checking
181 macros in tree.h. Changing the order will degrade the speed of the
184/* Complex number types. The TREE_TYPE field is the data type
185 of the real and imaginary parts. It must be of scalar
186 arithmetic type, not including pointer type. */
187DEFTREECODE (COMPLEX_TYPE, "complex_type", tcc_type, 0)
189/* Vector types. The TREE_TYPE field is the data type of the vector
190 elements. The TYPE_PRECISION field is the number of subparts of
191 the vector. */
192DEFTREECODE (VECTOR_TYPE, "vector_type", tcc_type, 0)
194/* The ordering of the following codes is optimized for the checking
195 macros in tree.h. Changing the order will degrade the speed of the
197 Note that this range overlaps the previous range. */
199/* Types of arrays. Special fields:
200 TREE_TYPE Type of an array element.
201 TYPE_DOMAIN Type to index by.
202 Its range of values specifies the array length.
203 The field TYPE_POINTER_TO (TREE_TYPE (array_type)) is always nonzero
204 and holds the type to coerce a value of that array type to in C.
205 TYPE_STRING_FLAG indicates a string (in contrast to an array of chars)
206 in languages (such as Chill) that make a distinction. */
207/* Array types in C or Pascal */
208DEFTREECODE (ARRAY_TYPE, "array_type", tcc_type, 0)
210/* Struct in C, or record in Pascal. */
211/* Special fields:
212 TYPE_FIELDS chain of FIELD_DECLs for the fields of the struct,
213 VAR_DECLs, TYPE_DECLs and CONST_DECLs for record-scope variables,
214 types and enumerators and FUNCTION_DECLs for methods associated
215 with the type.
216 A few may need to be added for Pascal. */
217/* See the comment above, before ENUMERAL_TYPE, for how
218 forward references to struct tags are handled in C. */
219DEFTREECODE (RECORD_TYPE, "record_type", tcc_type, 0)
221/* Union in C. Like a struct, except that the offsets of the fields
222 will all be zero. */
223/* See the comment above, before ENUMERAL_TYPE, for how
224 forward references to union tags are handled in C. */
225DEFTREECODE (UNION_TYPE, "union_type", tcc_type, 0) /* C union type */
227/* Similar to UNION_TYPE, except that the expressions in DECL_QUALIFIER
228 in each FIELD_DECL determine what the union contains. The first
229 field whose DECL_QUALIFIER expression is true is deemed to occupy
230 the union. */
231DEFTREECODE (QUAL_UNION_TYPE, "qual_union_type", tcc_type, 0)
233/* The ordering of the following codes is optimized for the checking
234 macros in tree.h. Changing the order will degrade the speed of the
237/* The void type in C */
238DEFTREECODE (VOID_TYPE, "void_type", tcc_type, 0)
240/* Type to hold bounds for a pointer.
241 Has TYPE_PRECISION component to specify number of bits used
242 by this type. */
243DEFTREECODE (POINTER_BOUNDS_TYPE, "pointer_bounds_type", tcc_type, 0)
245/* Type of functions. Special fields:
246 TREE_TYPE type of value returned.
247 TYPE_ARG_TYPES list of types of arguments expected.
248 this list is made of TREE_LIST nodes.
249 In this list TREE_PURPOSE can be used to indicate the default
250 value of parameter (used by C++ frontend).
251 Types of "Procedures" in languages where they are different from functions
252 have code FUNCTION_TYPE also, but then TREE_TYPE is zero or void type. */
253DEFTREECODE (FUNCTION_TYPE, "function_type", tcc_type, 0)
255/* METHOD_TYPE is the type of a function which takes an extra first
256 argument for "self", which is not present in the declared argument list.
257 The TREE_TYPE is the return type of the method. The TYPE_METHOD_BASETYPE
258 is the type of "self". TYPE_ARG_TYPES is the real argument list, which
259 includes the hidden argument for "self". */
260DEFTREECODE (METHOD_TYPE, "method_type", tcc_type, 0)
262/* This is a language-specific kind of type.
263 Its meaning is defined by the language front end.
264 layout_type does not know how to lay this out,
265 so the front-end must do so manually. */
266DEFTREECODE (LANG_TYPE, "lang_type", tcc_type, 0)
268/* Expressions */
270/* First, the constants. */
272DEFTREECODE (VOID_CST, "void_cst", tcc_constant, 0)
274/* Contents are in an array of HOST_WIDE_INTs.
276 We often access these constants both in their native precision and
277 in wider precisions (with the constant being implicitly extended
278 according to TYPE_SIGN). In each case, the useful part of the array
279 may be as wide as the precision requires but may be shorter when all
280 of the upper bits are sign bits. The length of the array when accessed
281 in the constant's native precision is given by TREE_INT_CST_NUNITS.
282 The length of the array when accessed in wider precisions is given
283 by TREE_INT_CST_EXT_NUNITS. Each element can be obtained using
286 INTEGER_CST nodes can be shared, and therefore should be considered
287 read only. They should be copied before setting a flag such as
289 it is known to be unique. INTEGER_CST nodes are created for the
290 integral types, for pointer types and for vector and float types in
291 some circumstances. */
292DEFTREECODE (INTEGER_CST, "integer_cst", tcc_constant, 0)
294/* Contents are in TREE_REAL_CST field. */
295DEFTREECODE (REAL_CST, "real_cst", tcc_constant, 0)
297/* Contents are in TREE_FIXED_CST field. */
298DEFTREECODE (FIXED_CST, "fixed_cst", tcc_constant, 0)
300/* Contents are in TREE_REALPART and TREE_IMAGPART fields,
301 whose contents are other constant nodes. */
302DEFTREECODE (COMPLEX_CST, "complex_cst", tcc_constant, 0)
304/* See generic.texi for details. */
305DEFTREECODE (VECTOR_CST, "vector_cst", tcc_constant, 0)
307/* Contents are TREE_STRING_LENGTH and the actual contents of the string. */
308DEFTREECODE (STRING_CST, "string_cst", tcc_constant, 0)
310/* Declarations. All references to names are represented as ..._DECL
311 nodes. The decls in one binding context are chained through the
312 TREE_CHAIN field. Each DECL has a DECL_NAME field which contains
313 an IDENTIFIER_NODE. (Some decls, most often labels, may have zero
314 as the DECL_NAME). DECL_CONTEXT points to the node representing
315 the context in which this declaration has its scope. For
316 FIELD_DECLs, this is the RECORD_TYPE, UNION_TYPE, or
317 QUAL_UNION_TYPE node that the field is a member of. For VAR_DECL,
319 points to either the FUNCTION_DECL for the containing function, the
320 RECORD_TYPE or UNION_TYPE for the containing type, or NULL_TREE or
321 a TRANSLATION_UNIT_DECL if the given decl has "file scope".
322 DECL_ABSTRACT_ORIGIN, if non-NULL, points to the original (abstract)
323 ..._DECL node of which this decl is an (inlined or template expanded)
324 instance.
325 The TREE_TYPE field holds the data type of the object, when relevant.
326 LABEL_DECLs have no data type. For TYPE_DECL, the TREE_TYPE field
327 contents are the type whose name is being declared.
329 and DECL_MODE fields exist in decl nodes just as in type nodes.
330 They are unused in LABEL_DECL, TYPE_DECL and CONST_DECL nodes.
332 DECL_FIELD_BIT_OFFSET holds an integer number of bits offset for
333 the location. DECL_VOFFSET holds an expression for a variable
334 offset; it is to be multiplied by DECL_VOFFSET_UNIT (an integer).
335 These fields are relevant only in FIELD_DECLs and PARM_DECLs.
337 DECL_INITIAL holds the value to initialize a variable to,
338 or the value of a constant. For a function, it holds the body
339 (a node of type BLOCK representing the function's binding contour
340 and whose body contains the function's statements.) For a LABEL_DECL
341 in C, it is a flag, nonzero if the label's definition has been seen.
343 PARM_DECLs use a special field:
344 DECL_ARG_TYPE is the type in which the argument is actually
345 passed, which may be different from its type within the function.
347 FUNCTION_DECLs use four special fields:
348 DECL_ARGUMENTS holds a chain of PARM_DECL nodes for the arguments.
349 DECL_RESULT holds a RESULT_DECL node for the value of a function.
350 The DECL_RTL field is 0 for a function that returns no value.
351 (C functions returning void have zero here.)
352 The TREE_TYPE field is the type in which the result is actually
353 returned. This is usually the same as the return type of the
354 FUNCTION_DECL, but it may be a wider integer type because of
355 promotion.
356 DECL_FUNCTION_CODE is a code number that is nonzero for
357 built-in functions. Its value is an enum built_in_function
358 that says which built-in function it is.
360 DECL_SOURCE_FILE holds a filename string and DECL_SOURCE_LINE
361 holds a line number. In some cases these can be the location of
362 a reference, if no definition has been seen.
364 DECL_ABSTRACT is nonzero if the decl represents an abstract instance
365 of a decl (i.e. one which is nested within an abstract instance of a
366 inline function. */
368DEFTREECODE (FUNCTION_DECL, "function_decl", tcc_declaration, 0)
369DEFTREECODE (LABEL_DECL, "label_decl", tcc_declaration, 0)
370/* The ordering of the following codes is optimized for the checking
371 macros in tree.h. Changing the order will degrade the speed of the
373 TYPE_DECL. */
374DEFTREECODE (FIELD_DECL, "field_decl", tcc_declaration, 0)
375DEFTREECODE (VAR_DECL, "var_decl", tcc_declaration, 0)
376DEFTREECODE (CONST_DECL, "const_decl", tcc_declaration, 0)
377DEFTREECODE (PARM_DECL, "parm_decl", tcc_declaration, 0)
378DEFTREECODE (TYPE_DECL, "type_decl", tcc_declaration, 0)
379DEFTREECODE (RESULT_DECL, "result_decl", tcc_declaration, 0)
381/* A "declaration" of a debug temporary. It should only appear in
382 DEBUG stmts. */
383DEFTREECODE (DEBUG_EXPR_DECL, "debug_expr_decl", tcc_declaration, 0)
385/* A stmt that marks the beginning of a source statement. */
386DEFTREECODE (DEBUG_BEGIN_STMT, "debug_begin_stmt", tcc_statement, 0)
388/* A namespace declaration. Namespaces appear in DECL_CONTEXT of other
389 _DECLs, providing a hierarchy of names. */
390DEFTREECODE (NAMESPACE_DECL, "namespace_decl", tcc_declaration, 0)
392/* A declaration import.
393 The C++ FE uses this to represent a using-directive; eg:
394 "using namespace foo".
395 But it could be used to represent any declaration import construct.
396 Whenever a declaration import appears in a lexical block, the BLOCK node
397 representing that lexical block in GIMPLE will contain an IMPORTED_DECL
398 node, linked via BLOCK_VARS accessor of the said BLOCK.
399 For a given NODE which code is IMPORTED_DECL,
400 IMPORTED_DECL_ASSOCIATED_DECL (NODE) accesses the imported declaration. */
401DEFTREECODE (IMPORTED_DECL, "imported_decl", tcc_declaration, 0)
403/* A namelist declaration.
404 The Fortran FE uses this to represent a namelist statement, e.g.:
405 NAMELIST /namelist-group-name/ namelist-group-object-list.
406 Whenever a declaration import appears in a lexical block, the BLOCK node
407 representing that lexical block in GIMPLE will contain an NAMELIST_DECL
408 node, linked via BLOCK_VARS accessor of the said BLOCK.
409 For a given NODE which code is NAMELIST_DECL,
410 NAMELIST_DECL_ASSOCIATED_DECL (NODE) accesses the imported declaration. */
411DEFTREECODE (NAMELIST_DECL, "namelist_decl", tcc_declaration, 0)
413/* A translation unit. This is not technically a declaration, since it
414 can't be looked up, but it's close enough. */
415DEFTREECODE (TRANSLATION_UNIT_DECL, "translation_unit_decl",\
416 tcc_declaration, 0)
418/* References to storage. */
420/* The ordering of the following codes is optimized for the classification
421 in handled_component_p. Keep them in a consecutive group. */
423/* Value is structure or union component.
424 Operand 0 is the structure or union (an expression).
425 Operand 1 is the field (a node of type FIELD_DECL).
426 Operand 2, if present, is the value of DECL_FIELD_OFFSET, measured
427 in units of DECL_OFFSET_ALIGN / BITS_PER_UNIT. */
428DEFTREECODE (COMPONENT_REF, "component_ref", tcc_reference, 3)
430/* Reference to a group of bits within an object. Similar to COMPONENT_REF
431 except the position is given explicitly rather than via a FIELD_DECL.
432 Operand 0 is the structure or union expression;
433 operand 1 is a tree giving the constant number of bits being referenced;
434 operand 2 is a tree giving the constant position of the first referenced bit.
435 The result type width has to match the number of bits referenced.
436 If the result type is integral, its signedness specifies how it is extended
437 to its mode width. */
438DEFTREECODE (BIT_FIELD_REF, "bit_field_ref", tcc_reference, 3)
440/* Array indexing.
441 Operand 0 is the array; operand 1 is a (single) array index.
442 Operand 2, if present, is a copy of TYPE_MIN_VALUE of the index.
443 Operand 3, if present, is the element size, measured in units of
444 the alignment of the element type. */
445DEFTREECODE (ARRAY_REF, "array_ref", tcc_reference, 4)
447/* Likewise, except that the result is a range ("slice") of the array. The
448 starting index of the resulting array is taken from operand 1 and the size
449 of the range is taken from the type of the expression. */
450DEFTREECODE (ARRAY_RANGE_REF, "array_range_ref", tcc_reference, 4)
452/* Used only on an operand of complex type, these return
453 a value of the corresponding component type. */
454DEFTREECODE (REALPART_EXPR, "realpart_expr", tcc_reference, 1)
455DEFTREECODE (IMAGPART_EXPR, "imagpart_expr", tcc_reference, 1)
457/* Represents viewing something of one type as being of a second type.
458 This corresponds to an "Unchecked Conversion" in Ada and roughly to
459 the idiom *(type2 *)&X in C. The only operand is the value to be
460 viewed as being of another type. It is undefined if the type of the
461 input and of the expression have different sizes.
463 This code may also be used within the LHS of a MODIFY_EXPR, in which
464 case no actual data motion may occur. TREE_ADDRESSABLE will be set in
465 this case and GCC must abort if it could not do the operation without
466 generating insns. */
467DEFTREECODE (VIEW_CONVERT_EXPR, "view_convert_expr", tcc_reference, 1)
469/* C unary `*' or Pascal `^'. One operand, an expression for a pointer. */
470DEFTREECODE (INDIRECT_REF, "indirect_ref", tcc_reference, 1)
472/* Used to represent lookup in a virtual method table which is dependent on
473 the runtime type of an object. Operands are:
474 OBJ_TYPE_REF_EXPR: An expression that evaluates the value to use.
475 OBJ_TYPE_REF_OBJECT: Is the object on whose behalf the lookup is
476 being performed. Through this the optimizers may be able to statically
477 determine the dynamic type of the object.
478 OBJ_TYPE_REF_TOKEN: An integer index to the virtual method table. */
479DEFTREECODE (OBJ_TYPE_REF, "obj_type_ref", tcc_expression, 3)
481/* Used to represent the brace-enclosed initializers for a structure or an
482 array. It contains a sequence of component values made out of a VEC of
483 constructor_elt.
486 The field INDEX of each constructor_elt is a FIELD_DECL.
489 The field INDEX of each constructor_elt is the corresponding index.
490 If the index is a RANGE_EXPR, it is a short-hand for many nodes,
491 one for each index in the range. (If the corresponding field VALUE
492 has side-effects, they are evaluated once for each element. Wrap the
493 value in a SAVE_EXPR if you want to evaluate side effects only once.)
495 Components that aren't present are cleared as per the C semantics,
496 unless the CONSTRUCTOR_NO_CLEARING flag is set, in which case their
497 value becomes undefined. */
498DEFTREECODE (CONSTRUCTOR, "constructor", tcc_exceptional, 0)
500/* The expression types are mostly straightforward, with the fourth argument
501 of DEFTREECODE saying how many operands there are.
502 Unless otherwise specified, the operands are expressions and the
503 types of all the operands and the expression must all be the same. */
505/* Contains two expressions to compute, one followed by the other.
506 the first value is ignored. The second one's value is used. The
507 type of the first expression need not agree with the other types. */
508DEFTREECODE (COMPOUND_EXPR, "compound_expr", tcc_expression, 2)
510/* Assignment expression. Operand 0 is the what to set; 1, the new value. */
511DEFTREECODE (MODIFY_EXPR, "modify_expr", tcc_expression, 2)
513/* Initialization expression. Operand 0 is the variable to initialize;
514 Operand 1 is the initializer. This differs from MODIFY_EXPR in that any
515 reference to the referent of operand 0 within operand 1 is undefined. */
516DEFTREECODE (INIT_EXPR, "init_expr", tcc_expression, 2)
518/* For TARGET_EXPR, operand 0 is the target of an initialization,
519 operand 1 is the initializer for the target, which may be void
520 if simply expanding it initializes the target.
521 operand 2 is the cleanup for this node, if any.
522 operand 3 is the saved initializer after this node has been
523 expanded once; this is so we can re-expand the tree later. */
524DEFTREECODE (TARGET_EXPR, "target_expr", tcc_expression, 4)
526/* Conditional expression ( ... ? ... : ... in C).
527 Operand 0 is the condition.
528 Operand 1 is the then-value.
529 Operand 2 is the else-value.
530 Operand 0 may be of any type.
531 Operand 1 must have the same type as the entire expression, unless
532 it unconditionally throws an exception, in which case it should
533 have VOID_TYPE. The same constraints apply to operand 2. The
534 condition in operand 0 must be of integral type.
536 In cfg gimple, if you do not have a selection expression, operands
537 1 and 2 are NULL. The operands are then taken from the cfg edges. */
538DEFTREECODE (COND_EXPR, "cond_expr", tcc_expression, 3)
540/* Vector conditional expression. It is like COND_EXPR, but with
541 vector operands.
543 A = VEC_COND_EXPR ( X < Y, B, C)
545 means
547 for (i=0; i<N; i++)
548 A[i] = X[i] < Y[i] ? B[i] : C[i];
550DEFTREECODE (VEC_COND_EXPR, "vec_cond_expr", tcc_expression, 3)
552/* Vector permutation expression. A = VEC_PERM_EXPR<v0, v1, mask> means
554 N = length(mask)
555 foreach i in N:
556 M = mask[i] % (2*N)
557 A = M < N ? v0[M] : v1[M-N]
559 V0 and V1 are vectors of the same type. MASK is an integer-typed
560 vector. The number of MASK elements must be the same with the
561 number of elements in V0 and V1. The size of the inner type
562 of the MASK and of the V0 and V1 must be the same.
564DEFTREECODE (VEC_PERM_EXPR, "vec_perm_expr", tcc_expression, 3)
566/* Declare local variables, including making RTL and allocating space.
567 BIND_EXPR_VARS is a chain of VAR_DECL nodes for the variables.
568 BIND_EXPR_BODY is the body, the expression to be computed using
569 the variables. The value of operand 1 becomes that of the BIND_EXPR.
570 BIND_EXPR_BLOCK is the BLOCK that corresponds to these bindings
571 for debugging purposes. If this BIND_EXPR is actually expanded,
572 that sets the TREE_USED flag in the BLOCK.
574 The BIND_EXPR is not responsible for informing parsers
575 about these variables. If the body is coming from the input file,
576 then the code that creates the BIND_EXPR is also responsible for
577 informing the parser of the variables.
579 If the BIND_EXPR is ever expanded, its TREE_USED flag is set.
580 This tells the code for debugging symbol tables not to ignore the BIND_EXPR.
581 If the BIND_EXPR should be output for debugging but will not be expanded,
582 set the TREE_USED flag by hand.
584 In order for the BIND_EXPR to be known at all, the code that creates it
585 must also install it as a subblock in the tree of BLOCK
586 nodes for the function. */
587DEFTREECODE (BIND_EXPR, "bind_expr", tcc_expression, 3)
589/* Function call. CALL_EXPRs are represented by variably-sized expression
590 nodes. There are at least three fixed operands. Operand 0 is an
591 INTEGER_CST node containing the total operand count, the number of
592 arguments plus 3. Operand 1 is the function or NULL, while operand 2 is
593 is static chain argument, or NULL. The remaining operands are the
594 arguments to the call. */
595DEFTREECODE (CALL_EXPR, "call_expr", tcc_vl_exp, 3)
597/* Specify a value to compute along with its corresponding cleanup.
598 Operand 0 is the cleanup expression.
599 The cleanup is executed by the first enclosing CLEANUP_POINT_EXPR,
600 which must exist. This differs from TRY_CATCH_EXPR in that operand 1
601 is always evaluated when cleanups are run. */
602DEFTREECODE (WITH_CLEANUP_EXPR, "with_cleanup_expr", tcc_expression, 1)
604/* Specify a cleanup point.
605 Operand 0 is an expression that may have cleanups. If it does, those
606 cleanups are executed after the expression is expanded.
608 Note that if the expression is a reference to storage, it is forced out
609 of memory before the cleanups are run. This is necessary to handle
610 cases where the cleanups modify the storage referenced; in the
611 expression 't.i', if 't' is a struct with an integer member 'i' and a
612 cleanup which modifies 'i', the value of the expression depends on
613 whether the cleanup is run before or after 't.i' is evaluated. When
614 expand_expr is run on 't.i', it returns a MEM. This is not good enough;
615 the value of 't.i' must be forced out of memory.
617 As a consequence, the operand of a CLEANUP_POINT_EXPR must not have
618 BLKmode, because it will not be forced out of memory. */
619DEFTREECODE (CLEANUP_POINT_EXPR, "cleanup_point_expr", tcc_expression, 1)
621/* The following code is used in languages that have types where some
622 field in an object of the type contains a value that is used in the
623 computation of another field's offset or size and/or the size of the
624 type. The positions and/or sizes of fields can vary from object to
625 object of the same type or even for one and the same object within
626 its scope.
628 Record types with discriminants in Ada or schema types in Pascal are
629 examples of such types. This mechanism is also used to create "fat
630 pointers" for unconstrained array types in Ada; the fat pointer is a
631 structure one of whose fields is a pointer to the actual array type
632 and the other field is a pointer to a template, which is a structure
633 containing the bounds of the array. The bounds in the type pointed
634 to by the first field in the fat pointer refer to the values in the
635 template.
637 When you wish to construct such a type you need "self-references"
638 that allow you to reference the object having this type from the
639 TYPE node, i.e. without having a variable instantiating this type.
641 Such a "self-references" is done using a PLACEHOLDER_EXPR. This is
642 a node that will later be replaced with the object being referenced.
643 Its type is that of the object and selects which object to use from
644 a chain of references (see below). No other slots are used in the
647 For example, if your type FOO is a RECORD_TYPE with a field BAR,
648 and you need the value of <variable>.BAR to calculate TYPE_SIZE
649 (FOO), just substitute <variable> above with a PLACEHOLDER_EXPR
650 whose TREE_TYPE is FOO. Then construct your COMPONENT_REF with
651 the PLACEHOLDER_EXPR as the first operand (which has the correct
652 type). Later, when the size is needed in the program, the back-end
653 will find this PLACEHOLDER_EXPR and generate code to calculate the
654 actual size at run-time. In the following, we describe how this
655 calculation is done.
657 When we wish to evaluate a size or offset, we check whether it contains a
658 PLACEHOLDER_EXPR. If it does, we call substitute_placeholder_in_expr
659 passing both that tree and an expression within which the object may be
660 found. The latter expression is the object itself in the simple case of
661 an Ada record with discriminant, but it can be the array in the case of an
662 unconstrained array.
664 In the latter case, we need the fat pointer, because the bounds of
665 the array can only be accessed from it. However, we rely here on the
666 fact that the expression for the array contains the dereference of
667 the fat pointer that obtained the array pointer. */
669/* Denotes a record to later be substituted before evaluating this expression.
670 The type of this expression is used to find the record to replace it. */
671DEFTREECODE (PLACEHOLDER_EXPR, "placeholder_expr", tcc_exceptional, 0)
673/* Simple arithmetic. */
674DEFTREECODE (PLUS_EXPR, "plus_expr", tcc_binary, 2)
675DEFTREECODE (MINUS_EXPR, "minus_expr", tcc_binary, 2)
676DEFTREECODE (MULT_EXPR, "mult_expr", tcc_binary, 2)
678/* Pointer addition. The first operand is always a pointer and the
679 second operand is an integer of type sizetype. */
680DEFTREECODE (POINTER_PLUS_EXPR, "pointer_plus_expr", tcc_binary, 2)
682/* Pointer subtraction. The two arguments are pointers, and the result
683 is a signed integer of the same precision. Pointers are interpreted
684 as unsigned, the difference is computed as if in infinite signed
685 precision. Behavior is undefined if the difference does not fit in
686 the result type. The result does not depend on the pointer type,
687 it is not divided by the size of the pointed-to type. */
688DEFTREECODE (POINTER_DIFF_EXPR, "pointer_diff_expr", tcc_binary, 2)
690/* Highpart multiplication. For an integral type with precision B,
691 returns bits [2B-1, B] of the full 2*B product. */
692DEFTREECODE (MULT_HIGHPART_EXPR, "mult_highpart_expr", tcc_binary, 2)
694/* Division for integer result that rounds the quotient toward zero. */
695DEFTREECODE (TRUNC_DIV_EXPR, "trunc_div_expr", tcc_binary, 2)
697/* Division for integer result that rounds it toward plus infinity. */
698DEFTREECODE (CEIL_DIV_EXPR, "ceil_div_expr", tcc_binary, 2)
700/* Division for integer result that rounds it toward minus infinity. */
701DEFTREECODE (FLOOR_DIV_EXPR, "floor_div_expr", tcc_binary, 2)
703/* Division for integer result that rounds it toward nearest integer. */
704DEFTREECODE (ROUND_DIV_EXPR, "round_div_expr", tcc_binary, 2)
706/* Four kinds of remainder that go with the four kinds of division: */
708/* The sign of the remainder is that of the dividend. */
709DEFTREECODE (TRUNC_MOD_EXPR, "trunc_mod_expr", tcc_binary, 2)
711/* The sign of the remainder is the opposite of that of the divisor. */
712DEFTREECODE (CEIL_MOD_EXPR, "ceil_mod_expr", tcc_binary, 2)
714/* The sign of the remainder is that of the divisor. */
715DEFTREECODE (FLOOR_MOD_EXPR, "floor_mod_expr", tcc_binary, 2)
717/* The sign of the remainder is not predictable. */
718DEFTREECODE (ROUND_MOD_EXPR, "round_mod_expr", tcc_binary, 2)
720/* Division for real result. */
721DEFTREECODE (RDIV_EXPR, "rdiv_expr", tcc_binary, 2)
723/* Division which is not supposed to need rounding.
724 Used for pointer subtraction in C. */
725DEFTREECODE (EXACT_DIV_EXPR, "exact_div_expr", tcc_binary, 2)
727/* Conversion of real to fixed point by truncation. */
728DEFTREECODE (FIX_TRUNC_EXPR, "fix_trunc_expr", tcc_unary, 1)
730/* Conversion of an integer to a real. */
731DEFTREECODE (FLOAT_EXPR, "float_expr", tcc_unary, 1)
733/* Unary negation. */
734DEFTREECODE (NEGATE_EXPR, "negate_expr", tcc_unary, 1)
736/* Minimum and maximum values. When used with floating point, if both
737 operands are zeros, or if either operand is NaN, then it is unspecified
738 which of the two operands is returned as the result. */
739DEFTREECODE (MIN_EXPR, "min_expr", tcc_binary, 2)
740DEFTREECODE (MAX_EXPR, "max_expr", tcc_binary, 2)
742/* Represents the absolute value of the operand.
744 An ABS_EXPR must have either an INTEGER_TYPE or a REAL_TYPE. The
745 operand of the ABS_EXPR must have the same type. */
746DEFTREECODE (ABS_EXPR, "abs_expr", tcc_unary, 1)
748/* Shift operations for shift and rotate.
749 Shift means logical shift if done on an
750 unsigned type, arithmetic shift if done on a signed type.
751 The second operand is the number of bits to
752 shift by; it need not be the same type as the first operand and result.
753 Note that the result is undefined if the second operand is larger
754 than or equal to the first operand's type size.
756 The first operand of a shift can have either an integer or a
757 (non-integer) fixed-point type. We follow the ISO/IEC TR 18037:2004
758 semantics for the latter.
760 Rotates are defined for integer types only. */
761DEFTREECODE (LSHIFT_EXPR, "lshift_expr", tcc_binary, 2)
762DEFTREECODE (RSHIFT_EXPR, "rshift_expr", tcc_binary, 2)
763DEFTREECODE (LROTATE_EXPR, "lrotate_expr", tcc_binary, 2)
764DEFTREECODE (RROTATE_EXPR, "rrotate_expr", tcc_binary, 2)
766/* Bitwise operations. Operands have same mode as result. */
767DEFTREECODE (BIT_IOR_EXPR, "bit_ior_expr", tcc_binary, 2)
768DEFTREECODE (BIT_XOR_EXPR, "bit_xor_expr", tcc_binary, 2)
769DEFTREECODE (BIT_AND_EXPR, "bit_and_expr", tcc_binary, 2)
770DEFTREECODE (BIT_NOT_EXPR, "bit_not_expr", tcc_unary, 1)
772/* ANDIF and ORIF allow the second operand not to be computed if the
773 value of the expression is determined from the first operand. AND,
774 OR, and XOR always compute the second operand whether its value is
775 needed or not (for side effects). The operand may have
776 BOOLEAN_TYPE or INTEGER_TYPE. In either case, the argument will be
777 either zero or one. For example, a TRUTH_NOT_EXPR will never have
778 an INTEGER_TYPE VAR_DECL as its argument; instead, a NE_EXPR will be
779 used to compare the VAR_DECL to zero, thereby obtaining a node with
780 value zero or one. */
781DEFTREECODE (TRUTH_ANDIF_EXPR, "truth_andif_expr", tcc_expression, 2)
782DEFTREECODE (TRUTH_ORIF_EXPR, "truth_orif_expr", tcc_expression, 2)
783DEFTREECODE (TRUTH_AND_EXPR, "truth_and_expr", tcc_expression, 2)
784DEFTREECODE (TRUTH_OR_EXPR, "truth_or_expr", tcc_expression, 2)
785DEFTREECODE (TRUTH_XOR_EXPR, "truth_xor_expr", tcc_expression, 2)
786DEFTREECODE (TRUTH_NOT_EXPR, "truth_not_expr", tcc_expression, 1)
788/* Relational operators.
789 `EQ_EXPR' and `NE_EXPR' are allowed for any types.
790 The others are allowed only for integer (or pointer or enumeral)
791 or real types.
792 In all cases the operands will have the same type,
793 and the value is either the type used by the language for booleans
794 or an integer vector type of the same size and with the same number
795 of elements as the comparison operands. True for a vector of
796 comparison results has all bits set while false is equal to zero. */
797DEFTREECODE (LT_EXPR, "lt_expr", tcc_comparison, 2)
798DEFTREECODE (LE_EXPR, "le_expr", tcc_comparison, 2)
799DEFTREECODE (GT_EXPR, "gt_expr", tcc_comparison, 2)
800DEFTREECODE (GE_EXPR, "ge_expr", tcc_comparison, 2)
801DEFTREECODE (EQ_EXPR, "eq_expr", tcc_comparison, 2)
802DEFTREECODE (NE_EXPR, "ne_expr", tcc_comparison, 2)
804/* Additional relational operators for floating point unordered. */
805DEFTREECODE (UNORDERED_EXPR, "unordered_expr", tcc_comparison, 2)
806DEFTREECODE (ORDERED_EXPR, "ordered_expr", tcc_comparison, 2)
808/* These are equivalent to unordered or ... */
809DEFTREECODE (UNLT_EXPR, "unlt_expr", tcc_comparison, 2)
810DEFTREECODE (UNLE_EXPR, "unle_expr", tcc_comparison, 2)
811DEFTREECODE (UNGT_EXPR, "ungt_expr", tcc_comparison, 2)
812DEFTREECODE (UNGE_EXPR, "unge_expr", tcc_comparison, 2)
813DEFTREECODE (UNEQ_EXPR, "uneq_expr", tcc_comparison, 2)
815/* This is the reverse of uneq_expr. */
816DEFTREECODE (LTGT_EXPR, "ltgt_expr", tcc_comparison, 2)
818DEFTREECODE (RANGE_EXPR, "range_expr", tcc_binary, 2)
820/* Represents a re-association barrier for floating point expressions
821 like explicit parenthesis in fortran. */
822DEFTREECODE (PAREN_EXPR, "paren_expr", tcc_unary, 1)
824/* Represents a conversion of type of a value.
825 All conversions, including implicit ones, must be
826 represented by CONVERT_EXPR or NOP_EXPR nodes. */
827DEFTREECODE (CONVERT_EXPR, "convert_expr", tcc_unary, 1)
829/* Conversion of a pointer value to a pointer to a different
830 address space. */
831DEFTREECODE (ADDR_SPACE_CONVERT_EXPR, "addr_space_convert_expr", tcc_unary, 1)
833/* Conversion of a fixed-point value to an integer, a real, or a fixed-point
834 value. Or conversion of a fixed-point value from an integer, a real, or
835 a fixed-point value. */
836DEFTREECODE (FIXED_CONVERT_EXPR, "fixed_convert_expr", tcc_unary, 1)
838/* Represents a conversion expected to require no code to be generated. */
839DEFTREECODE (NOP_EXPR, "nop_expr", tcc_unary, 1)
841/* Value is same as argument, but guaranteed not an lvalue. */
842DEFTREECODE (NON_LVALUE_EXPR, "non_lvalue_expr", tcc_unary, 1)
844/* A COMPOUND_LITERAL_EXPR represents a literal that is placed in a DECL. The
845 COMPOUND_LITERAL_EXPR_DECL_EXPR is the a DECL_EXPR containing the decl
846 for the anonymous object represented by the COMPOUND_LITERAL;
847 the DECL_INITIAL of that decl is the CONSTRUCTOR that initializes
848 the compound literal. */
849DEFTREECODE (COMPOUND_LITERAL_EXPR, "compound_literal_expr", tcc_expression, 1)
851/* Represents something we computed once and will use multiple times.
852 First operand is that expression. After it is evaluated once, it
853 will be replaced by the temporary variable that holds the value. */
854DEFTREECODE (SAVE_EXPR, "save_expr", tcc_expression, 1)
856/* & in C. Value is the address at which the operand's value resides.
857 Operand may have any mode. Result mode is Pmode. */
858DEFTREECODE (ADDR_EXPR, "addr_expr", tcc_expression, 1)
860/* Operand0 is a function constant; result is part N of a function
861 descriptor of type ptr_mode. */
862DEFTREECODE (FDESC_EXPR, "fdesc_expr", tcc_expression, 2)
864/* Given a container value, a replacement value and a bit position within
865 the container, produce the value that results from replacing the part of
866 the container starting at the bit position with the replacement value.
867 Operand 0 is a tree for the container value of integral or vector type;
868 Operand 1 is a tree for the replacement value of another integral or
869 the vector element type;
870 Operand 2 is a tree giving the constant bit position;
871 The number of bits replaced is given by the precision of the type of the
872 replacement value if it is integral or by its size if it is non-integral.
873 ??? The reason to make the size of the replacement implicit is to avoid
874 introducing a quaternary operation.
875 The replaced bits shall be fully inside the container. If the container
876 is of vector type, then these bits shall be aligned with its elements. */
877DEFTREECODE (BIT_INSERT_EXPR, "bit_insert_expr", tcc_expression, 3)
879/* Given two real or integer operands of the same type,
880 returns a complex value of the corresponding complex type. */
881DEFTREECODE (COMPLEX_EXPR, "complex_expr", tcc_binary, 2)
883/* Complex conjugate of operand. Used only on complex types. */
884DEFTREECODE (CONJ_EXPR, "conj_expr", tcc_unary, 1)
886/* Nodes for ++ and -- in C.
887 The second arg is how much to increment or decrement by.
888 For a pointer, it would be the size of the object pointed to. */
889DEFTREECODE (PREDECREMENT_EXPR, "predecrement_expr", tcc_expression, 2)
890DEFTREECODE (PREINCREMENT_EXPR, "preincrement_expr", tcc_expression, 2)
891DEFTREECODE (POSTDECREMENT_EXPR, "postdecrement_expr", tcc_expression, 2)
892DEFTREECODE (POSTINCREMENT_EXPR, "postincrement_expr", tcc_expression, 2)
894/* Used to implement `va_arg'. */
895DEFTREECODE (VA_ARG_EXPR, "va_arg_expr", tcc_expression, 1)
897/* Evaluate operand 0. If and only if an exception is thrown during
898 the evaluation of operand 0, evaluate operand 1.
900 This differs from TRY_FINALLY_EXPR in that operand 1 is not evaluated
901 on a normal or jump exit, only on an exception. */
902DEFTREECODE (TRY_CATCH_EXPR, "try_catch_expr", tcc_statement, 2)
904/* Evaluate the first operand.
905 The second operand is a cleanup expression which is evaluated
906 on any exit (normal, exception, or jump out) from this expression. */
907DEFTREECODE (TRY_FINALLY_EXPR, "try_finally", tcc_statement, 2)
909/* These types of expressions have no useful value,
910 and always have side effects. */
912/* Used to represent a local declaration. The operand is DECL_EXPR_DECL. */
913DEFTREECODE (DECL_EXPR, "decl_expr", tcc_statement, 1)
915/* A label definition, encapsulated as a statement.
916 Operand 0 is the LABEL_DECL node for the label that appears here.
917 The type should be void and the value should be ignored. */
918DEFTREECODE (LABEL_EXPR, "label_expr", tcc_statement, 1)
920/* GOTO. Operand 0 is a LABEL_DECL node or an expression.
921 The type should be void and the value should be ignored. */
922DEFTREECODE (GOTO_EXPR, "goto_expr", tcc_statement, 1)
924/* RETURN. Evaluates operand 0, then returns from the current function.
925 Presumably that operand is an assignment that stores into the
926 RESULT_DECL that hold the value to be returned.
927 The operand may be null.
928 The type should be void and the value should be ignored. */
929DEFTREECODE (RETURN_EXPR, "return_expr", tcc_statement, 1)
931/* Exit the inner most loop conditionally. Operand 0 is the condition.
932 The type should be void and the value should be ignored. */
933DEFTREECODE (EXIT_EXPR, "exit_expr", tcc_statement, 1)
935/* A loop. Operand 0 is the body of the loop.
936 It must contain an EXIT_EXPR or is an infinite loop.
937 The type should be void and the value should be ignored. */
938DEFTREECODE (LOOP_EXPR, "loop_expr", tcc_statement, 1)
940/* Switch expression.
942 TREE_TYPE is the original type of the condition, before any
943 language required type conversions. It may be NULL, in which case
944 the original type and final types are assumed to be the same.
946 Operand 0 is the expression used to perform the branch,
947 Operand 1 is the body of the switch, which probably contains
948 CASE_LABEL_EXPRs. It may also be NULL, in which case operand 2
949 must not be NULL. */
950DEFTREECODE (SWITCH_EXPR, "switch_expr", tcc_statement, 2)
952/* Used to represent a case label.
954 Operand 0 is CASE_LOW. It may be NULL_TREE, in which case the label
955 is a 'default' label.
956 Operand 1 is CASE_HIGH. If it is NULL_TREE, the label is a simple
957 (one-value) case label. If it is non-NULL_TREE, the case is a range.
958 Operand 2 is CASE_LABEL, which is is the corresponding LABEL_DECL.
959 Operand 3 is CASE_CHAIN. This operand is only used in tree-cfg.c to
960 speed up the lookup of case labels which use a particular edge in
961 the control flow graph. */
962DEFTREECODE (CASE_LABEL_EXPR, "case_label_expr", tcc_statement, 4)
964/* Used to represent an inline assembly statement. ASM_STRING returns a
965 STRING_CST for the instruction (e.g., "mov x, y"). ASM_OUTPUTS,
966 ASM_INPUTS, and ASM_CLOBBERS represent the outputs, inputs, and clobbers
967 for the statement. ASM_LABELS, if present, indicates various destinations
968 for the asm; labels cannot be combined with outputs. */
969DEFTREECODE (ASM_EXPR, "asm_expr", tcc_statement, 5)
971/* Variable references for SSA analysis. New SSA names are created every
972 time a variable is assigned a new value. The SSA builder uses SSA_NAME
973 nodes to implement SSA versioning. */
974DEFTREECODE (SSA_NAME, "ssa_name", tcc_exceptional, 0)
976/* Used to represent a typed exception handler. CATCH_TYPES is the type (or
977 list of types) handled, and CATCH_BODY is the code for the handler. */
978DEFTREECODE (CATCH_EXPR, "catch_expr", tcc_statement, 2)
980/* Used to represent an exception specification. EH_FILTER_TYPES is a list
981 of allowed types, and EH_FILTER_FAILURE is an expression to evaluate on
982 failure. */
983DEFTREECODE (EH_FILTER_EXPR, "eh_filter_expr", tcc_statement, 2)
985/* Node used for describing a property that is known at compile
986 time. */
987DEFTREECODE (SCEV_KNOWN, "scev_known", tcc_expression, 0)
989/* Node used for describing a property that is not known at compile
990 time. */
991DEFTREECODE (SCEV_NOT_KNOWN, "scev_not_known", tcc_expression, 0)
993/* Polynomial chains of recurrences.
994 cr = {CHREC_LEFT (cr), +, CHREC_RIGHT (cr)}_CHREC_VARIABLE (cr). */
995DEFTREECODE (POLYNOMIAL_CHREC, "polynomial_chrec", tcc_expression, 2)
997/* Used to chain children of container statements together.
998 Use the interface in tree-iterator.h to access this node. */
999DEFTREECODE (STATEMENT_LIST, "statement_list", tcc_exceptional, 0)
1001/* Predicate assertion. Artificial expression generated by the optimizers
1002 to keep track of predicate values. This expression may only appear on
1003 the RHS of assignments.
1005 Given X = ASSERT_EXPR <Y, EXPR>, the optimizers can infer
1006 two things:
1008 1- X is a copy of Y.
1009 2- EXPR is a conditional expression and is known to be true.
1011 Valid and to be expected forms of conditional expressions are
1012 valid GIMPLE conditional expressions (as defined by is_gimple_condexpr)
1013 and conditional expressions with the first operand being a
1014 PLUS_EXPR with a variable possibly wrapped in a NOP_EXPR first
1015 operand and an integer constant second operand.
1017 The type of the expression is the same as Y. */
1018DEFTREECODE (ASSERT_EXPR, "assert_expr", tcc_expression, 2)
1020/* Base class information. Holds information about a class as a
1021 baseclass of itself or another class. */
1022DEFTREECODE (TREE_BINFO, "tree_binfo", tcc_exceptional, 0)
1024/* Records the size for an expression of variable size type. This is
1025 for use in contexts in which we are accessing the entire object,
1026 such as for a function call, or block copy.
1027 Operand 0 is the real expression.
1028 Operand 1 is the size of the type in the expression. */
1029DEFTREECODE (WITH_SIZE_EXPR, "with_size_expr", tcc_expression, 2)
1031/* Extract elements from two input vectors Operand 0 and Operand 1
1032 size VS, according to the offset OFF defined by Operand 2 as
1033 follows:
1034 If OFF > 0, the last VS - OFF elements of vector OP0 are concatenated to
1035 the first OFF elements of the vector OP1.
1036 If OFF == 0, then the returned vector is OP1.
1037 On different targets OFF may take different forms; It can be an address, in
1038 which case its low log2(VS)-1 bits define the offset, or it can be a mask
1039 generated by the builtin targetm.vectorize.mask_for_load_builtin_decl. */
1040DEFTREECODE (REALIGN_LOAD_EXPR, "realign_load", tcc_expression, 3)
1042/* Low-level memory addressing. Operands are BASE (address of static or
1043 global variable or register), OFFSET (integer constant),
1044 INDEX (register), STEP (integer constant), INDEX2 (register),
1045 The corresponding address is BASE + STEP * INDEX + INDEX2 + OFFSET.
1046 Only variations and values valid on the target are allowed.
1048 The type of STEP, INDEX and INDEX2 is sizetype.
1050 The type of BASE is a pointer type. If BASE is not an address of
1051 a static or global variable INDEX2 will be NULL.
1053 The type of OFFSET is a pointer type and determines TBAA the same as
1054 the constant offset operand in MEM_REF. */
1056DEFTREECODE (TARGET_MEM_REF, "target_mem_ref", tcc_reference, 5)
1058/* Memory addressing. Operands are a pointer and a tree constant integer
1059 byte offset of the pointer type that when dereferenced yields the
1060 type of the base object the pointer points into and which is used for
1061 TBAA purposes.
1062 The type of the MEM_REF is the type the bytes at the memory location
1063 are interpreted as.
1064 MEM_REF <p, c> is equivalent to ((typeof(c))p)->x... where x... is a
1065 chain of component references offsetting p by c. */
1066DEFTREECODE (MEM_REF, "mem_ref", tcc_reference, 2)
1068/* OpenACC and OpenMP. As it is exposed in TREE_RANGE_CHECK invocations, do
1069 not change the ordering of these codes. */
1071/* OpenACC - #pragma acc parallel [clause1 ... clauseN]
1072 Operand 0: OMP_BODY: Code to be executed in parallel.
1073 Operand 1: OMP_CLAUSES: List of clauses. */
1075DEFTREECODE (OACC_PARALLEL, "oacc_parallel", tcc_statement, 2)
1077/* OpenACC - #pragma acc kernels [clause1 ... clauseN]
1078 Operand 0: OMP_BODY: Sequence of kernels.
1079 Operand 1: OMP_CLAUSES: List of clauses. */
1081DEFTREECODE (OACC_KERNELS, "oacc_kernels", tcc_statement, 2)
1083/* OpenACC - #pragma acc data [clause1 ... clauseN]
1084 Operand 0: OACC_DATA_BODY: Data construct body.
1085 Operand 1: OACC_DATA_CLAUSES: List of clauses. */
1087DEFTREECODE (OACC_DATA, "oacc_data", tcc_statement, 2)
1089/* OpenACC - #pragma acc host_data [clause1 ... clauseN]
1090 Operand 0: OACC_HOST_DATA_BODY: Host_data construct body.
1091 Operand 1: OACC_HOST_DATA_CLAUSES: List of clauses. */
1093DEFTREECODE (OACC_HOST_DATA, "oacc_host_data", tcc_statement, 2)
1095/* OpenMP - #pragma omp parallel [clause1 ... clauseN]
1096 Operand 0: OMP_PARALLEL_BODY: Code to be executed by all threads.
1097 Operand 1: OMP_PARALLEL_CLAUSES: List of clauses. */
1099DEFTREECODE (OMP_PARALLEL, "omp_parallel", tcc_statement, 2)
1101/* OpenMP - #pragma omp task [clause1 ... clauseN]
1102 Operand 0: OMP_TASK_BODY: Code to be executed by all threads.
1103 Operand 1: OMP_TASK_CLAUSES: List of clauses. */
1105DEFTREECODE (OMP_TASK, "omp_task", tcc_statement, 2)
1107/* OpenMP - #pragma omp for [clause1 ... clauseN]
1108 Operand 0: OMP_FOR_BODY: Loop body.
1109 Operand 1: OMP_FOR_CLAUSES: List of clauses.
1110 Operand 2: OMP_FOR_INIT: Initialization code of the form
1111 VAR = N1.
1112 Operand 3: OMP_FOR_COND: Loop conditional expression of the form
1113 VAR { <, >, <=, >= } N2.
1114 Operand 4: OMP_FOR_INCR: Loop index increment of the form
1115 VAR { +=, -= } INCR.
1116 Operand 5: OMP_FOR_PRE_BODY: Filled by the gimplifier with things
1117 from INIT, COND, and INCR that are technically part of the
1118 OMP_FOR structured block, but are evaluated before the loop
1119 body begins.
1120 Operand 6: OMP_FOR_ORIG_DECLS: If non-NULL, list of DECLs initialized
1121 in OMP_FOR_INIT. In some cases, like C++ iterators, the original
1122 DECL init has been lost in gimplification and now contains a
1123 temporary (D.nnnn). This list contains the original DECLs in
1124 the source.
1126 VAR must be an integer or pointer variable, which is implicitly thread
1127 private. N1, N2 and INCR are required to be loop invariant integer
1128 expressions that are evaluated without any synchronization.
1129 The evaluation order, frequency of evaluation and side-effects are
1130 unspecified by the standards. */
1131DEFTREECODE (OMP_FOR, "omp_for", tcc_statement, 7)
1133/* OpenMP - #pragma omp simd [clause1 ... clauseN]
1134 Operands like for OMP_FOR. */
1135DEFTREECODE (OMP_SIMD, "omp_simd", tcc_statement, 7)
1137/* OpenMP - #pragma omp distribute [clause1 ... clauseN]
1138 Operands like for OMP_FOR. */
1139DEFTREECODE (OMP_DISTRIBUTE, "omp_distribute", tcc_statement, 7)
1141/* OpenMP - #pragma omp taskloop [clause1 ... clauseN]
1142 Operands like for OMP_FOR. */
1143DEFTREECODE (OMP_TASKLOOP, "omp_taskloop", tcc_statement, 7)
1145/* OpenMP - #pragma acc loop [clause1 ... clauseN]
1146 Operands like for OMP_FOR. */
1147DEFTREECODE (OACC_LOOP, "oacc_loop", tcc_statement, 7)
1149/* OpenMP - #pragma omp teams [clause1 ... clauseN]
1150 Operand 0: OMP_TEAMS_BODY: Teams body.
1151 Operand 1: OMP_TEAMS_CLAUSES: List of clauses. */
1152DEFTREECODE (OMP_TEAMS, "omp_teams", tcc_statement, 2)
1154/* OpenMP - #pragma omp target data [clause1 ... clauseN]
1155 Operand 0: OMP_TARGET_DATA_BODY: Target data construct body.
1156 Operand 1: OMP_TARGET_DATA_CLAUSES: List of clauses. */
1157DEFTREECODE (OMP_TARGET_DATA, "omp_target_data", tcc_statement, 2)
1159/* OpenMP - #pragma omp target [clause1 ... clauseN]
1160 Operand 0: OMP_TARGET_BODY: Target construct body.
1161 Operand 1: OMP_TARGET_CLAUSES: List of clauses. */
1162DEFTREECODE (OMP_TARGET, "omp_target", tcc_statement, 2)
1164/* OpenMP - #pragma omp sections [clause1 ... clauseN]
1165 Operand 0: OMP_SECTIONS_BODY: Sections body.
1166 Operand 1: OMP_SECTIONS_CLAUSES: List of clauses. */
1167DEFTREECODE (OMP_SECTIONS, "omp_sections", tcc_statement, 2)
1169/* OpenMP - #pragma omp ordered
1170 Operand 0: OMP_ORDERED_BODY: Master section body.
1171 Operand 1: OMP_ORDERED_CLAUSES: List of clauses. */
1172DEFTREECODE (OMP_ORDERED, "omp_ordered", tcc_statement, 2)
1174/* OpenMP - #pragma omp critical [name]
1175 Operand 0: OMP_CRITICAL_BODY: Critical section body.
1176 Operand 1: OMP_CRITICAL_CLAUSES: List of clauses.
1177 Operand 2: OMP_CRITICAL_NAME: Identifier for critical section. */
1178DEFTREECODE (OMP_CRITICAL, "omp_critical", tcc_statement, 3)
1180/* OpenMP - #pragma omp single
1181 Operand 0: OMP_SINGLE_BODY: Single section body.
1182 Operand 1: OMP_SINGLE_CLAUSES: List of clauses. */
1183DEFTREECODE (OMP_SINGLE, "omp_single", tcc_statement, 2)
1185/* OpenMP - #pragma omp section
1186 Operand 0: OMP_SECTION_BODY: Section body. */
1187DEFTREECODE (OMP_SECTION, "omp_section", tcc_statement, 1)
1189/* OpenMP - #pragma omp master
1190 Operand 0: OMP_MASTER_BODY: Master section body. */
1191DEFTREECODE (OMP_MASTER, "omp_master", tcc_statement, 1)
1193/* OpenMP - #pragma omp taskgroup
1194 Operand 0: OMP_TASKGROUP_BODY: Taskgroup body. */
1195DEFTREECODE (OMP_TASKGROUP, "omp_taskgroup", tcc_statement, 1)
1197/* OpenACC - #pragma acc cache (variable1 ... variableN)
1198 Operand 0: OACC_CACHE_CLAUSES: List of variables (transformed into
1199 OMP_CLAUSE__CACHE_ clauses). */
1200DEFTREECODE (OACC_CACHE, "oacc_cache", tcc_statement, 1)
1202/* OpenACC - #pragma acc declare [clause1 ... clauseN]
1203 Operand 0: OACC_DECLARE_CLAUSES: List of clauses. */
1204DEFTREECODE (OACC_DECLARE, "oacc_declare", tcc_statement, 1)
1206/* OpenACC - #pragma acc enter data [clause1 ... clauseN]
1207 Operand 0: OACC_ENTER_DATA_CLAUSES: List of clauses. */
1208DEFTREECODE (OACC_ENTER_DATA, "oacc_enter_data", tcc_statement, 1)
1210/* OpenACC - #pragma acc exit data [clause1 ... clauseN]
1211 Operand 0: OACC_EXIT_DATA_CLAUSES: List of clauses. */
1212DEFTREECODE (OACC_EXIT_DATA, "oacc_exit_data", tcc_statement, 1)
1214/* OpenACC - #pragma acc update [clause1 ... clauseN]
1215 Operand 0: OACC_UPDATE_CLAUSES: List of clauses. */
1216DEFTREECODE (OACC_UPDATE, "oacc_update", tcc_statement, 1)
1218/* OpenMP - #pragma omp target update [clause1 ... clauseN]
1219 Operand 0: OMP_TARGET_UPDATE_CLAUSES: List of clauses. */
1220DEFTREECODE (OMP_TARGET_UPDATE, "omp_target_update", tcc_statement, 1)
1222/* OpenMP - #pragma omp target enter data [clause1 ... clauseN]
1223 Operand 0: OMP_TARGET_ENTER_DATA_CLAUSES: List of clauses. */
1224DEFTREECODE (OMP_TARGET_ENTER_DATA, "omp_target_enter_data", tcc_statement, 1)
1226/* OpenMP - #pragma omp target exit data [clause1 ... clauseN]
1227 Operand 0: OMP_TARGET_EXIT_DATA_CLAUSES: List of clauses. */
1228DEFTREECODE (OMP_TARGET_EXIT_DATA, "omp_target_exit_data", tcc_statement, 1)
1230/* OMP_ATOMIC through OMP_ATOMIC_CAPTURE_NEW must be consecutive,
1231 or OMP_ATOMIC_SEQ_CST needs adjusting. */
1233/* OpenMP - #pragma omp atomic
1234 Operand 0: The address at which the atomic operation is to be performed.
1235 This address should be stabilized with save_expr.
1236 Operand 1: The expression to evaluate. When the old value of the object
1237 at the address is used in the expression, it should appear as if
1238 build_fold_indirect_ref of the address. */
1239DEFTREECODE (OMP_ATOMIC, "omp_atomic", tcc_statement, 2)
1241/* OpenMP - #pragma omp atomic read
1242 Operand 0: The address at which the atomic operation is to be performed.
1243 This address should be stabilized with save_expr. */
1244DEFTREECODE (OMP_ATOMIC_READ, "omp_atomic_read", tcc_statement, 1)
1246/* OpenMP - #pragma omp atomic capture
1247 Operand 0: The address at which the atomic operation is to be performed.
1248 This address should be stabilized with save_expr.
1249 Operand 1: The expression to evaluate. When the old value of the object
1250 at the address is used in the expression, it should appear as if
1251 build_fold_indirect_ref of the address.
1252 OMP_ATOMIC_CAPTURE_OLD returns the old memory content,
1253 OMP_ATOMIC_CAPTURE_NEW the new value. */
1254DEFTREECODE (OMP_ATOMIC_CAPTURE_OLD, "omp_atomic_capture_old", tcc_statement, 2)
1255DEFTREECODE (OMP_ATOMIC_CAPTURE_NEW, "omp_atomic_capture_new", tcc_statement, 2)
1257/* OpenMP clauses. */
1258DEFTREECODE (OMP_CLAUSE, "omp_clause", tcc_exceptional, 0)
1260/* TRANSACTION_EXPR tree code.
1261 Operand 0: BODY: contains body of the transaction. */
1262DEFTREECODE (TRANSACTION_EXPR, "transaction_expr", tcc_expression, 1)
1264/* Widening dot-product.
1265 The first two arguments are of type t1.
1266 The third argument and the result are of type t2, such that t2 is at least
1267 twice the size of t1. DOT_PROD_EXPR(arg1,arg2,arg3) is equivalent to:
1268 tmp = WIDEN_MULT_EXPR(arg1, arg2);
1269 arg3 = PLUS_EXPR (tmp, arg3);
1270 or:
1271 tmp = WIDEN_MULT_EXPR(arg1, arg2);
1272 arg3 = WIDEN_SUM_EXPR (tmp, arg3); */
1273DEFTREECODE (DOT_PROD_EXPR, "dot_prod_expr", tcc_expression, 3)
1275/* Widening summation.
1276 The first argument is of type t1.
1277 The second argument is of type t2, such that t2 is at least twice
1278 the size of t1. The type of the entire expression is also t2.
1279 WIDEN_SUM_EXPR is equivalent to first widening (promoting)
1280 the first argument from type t1 to type t2, and then summing it
1281 with the second argument. */
1282DEFTREECODE (WIDEN_SUM_EXPR, "widen_sum_expr", tcc_binary, 2)
1284/* Widening sad (sum of absolute differences).
1285 The first two arguments are of type t1 which should be integer.
1286 The third argument and the result are of type t2, such that t2 is at least
1287 twice the size of t1. Like DOT_PROD_EXPR, SAD_EXPR (arg1,arg2,arg3) is
1288 equivalent to (note we don't have WIDEN_MINUS_EXPR now, but we assume its
1289 behavior is similar to WIDEN_SUM_EXPR):
1290 tmp = WIDEN_MINUS_EXPR (arg1, arg2)
1291 tmp2 = ABS_EXPR (tmp)
1292 arg3 = PLUS_EXPR (tmp2, arg3)
1293 or:
1294 tmp = WIDEN_MINUS_EXPR (arg1, arg2)
1295 tmp2 = ABS_EXPR (tmp)
1296 arg3 = WIDEN_SUM_EXPR (tmp2, arg3)
1297 */
1298DEFTREECODE (SAD_EXPR, "sad_expr", tcc_expression, 3)
1300/* Widening multiplication.
1301 The two arguments are of type t1.
1302 The result is of type t2, such that t2 is at least twice
1303 the size of t1. WIDEN_MULT_EXPR is equivalent to first widening (promoting)
1304 the arguments from type t1 to type t2, and then multiplying them. */
1305DEFTREECODE (WIDEN_MULT_EXPR, "widen_mult_expr", tcc_binary, 2)
1307/* Widening multiply-accumulate.
1308 The first two arguments are of type t1.
1309 The third argument and the result are of type t2, such as t2 is at least
1310 twice the size of t1. t1 and t2 must be integral or fixed-point types.
1311 The expression is equivalent to a WIDEN_MULT_EXPR operation
1312 of the first two operands followed by an add or subtract of the third
1313 operand. */
1314DEFTREECODE (WIDEN_MULT_PLUS_EXPR, "widen_mult_plus_expr", tcc_expression, 3)
1315/* This is like the above, except in the final expression the multiply result
1316 is subtracted from t3. */
1317DEFTREECODE (WIDEN_MULT_MINUS_EXPR, "widen_mult_minus_expr", tcc_expression, 3)
1319/* Widening shift left.
1320 The first operand is of type t1.
1321 The second operand is the number of bits to shift by; it need not be the
1322 same type as the first operand and result.
1323 Note that the result is undefined if the second operand is larger
1324 than or equal to the first operand's type size.
1325 The type of the entire expression is t2, such that t2 is at least twice
1326 the size of t1.
1327 WIDEN_LSHIFT_EXPR is equivalent to first widening (promoting)
1328 the first argument from type t1 to type t2, and then shifting it
1329 by the second argument. */
1330DEFTREECODE (WIDEN_LSHIFT_EXPR, "widen_lshift_expr", tcc_binary, 2)
1332/* Fused multiply-add.
1333 All operands and the result are of the same type. No intermediate
1334 rounding is performed after multiplying operand one with operand two
1335 before adding operand three. */
1336DEFTREECODE (FMA_EXPR, "fma_expr", tcc_expression, 3)
1338/* Widening vector multiplication.
1339 The two operands are vectors with N elements of size S. Multiplying the
1340 elements of the two vectors will result in N products of size 2*S.
1341 VEC_WIDEN_MULT_HI_EXPR computes the N/2 high products.
1342 VEC_WIDEN_MULT_LO_EXPR computes the N/2 low products. */
1343DEFTREECODE (VEC_WIDEN_MULT_HI_EXPR, "widen_mult_hi_expr", tcc_binary, 2)
1344DEFTREECODE (VEC_WIDEN_MULT_LO_EXPR, "widen_mult_lo_expr", tcc_binary, 2)
1346/* Similarly, but return the even or odd N/2 products. */
1347DEFTREECODE (VEC_WIDEN_MULT_EVEN_EXPR, "widen_mult_even_expr", tcc_binary, 2)
1348DEFTREECODE (VEC_WIDEN_MULT_ODD_EXPR, "widen_mult_odd_expr", tcc_binary, 2)
1350/* Unpack (extract and promote/widen) the high/low elements of the input
1351 vector into the output vector. The input vector has twice as many
1352 elements as the output vector, that are half the size of the elements
1353 of the output vector. This is used to support type promotion. */
1354DEFTREECODE (VEC_UNPACK_HI_EXPR, "vec_unpack_hi_expr", tcc_unary, 1)
1355DEFTREECODE (VEC_UNPACK_LO_EXPR, "vec_unpack_lo_expr", tcc_unary, 1)
1357/* Unpack (extract) the high/low elements of the input vector, convert
1358 fixed point values to floating point and widen elements into the
1359 output vector. The input vector has twice as many elements as the output
1360 vector, that are half the size of the elements of the output vector. */
1361DEFTREECODE (VEC_UNPACK_FLOAT_HI_EXPR, "vec_unpack_float_hi_expr", tcc_unary, 1)
1362DEFTREECODE (VEC_UNPACK_FLOAT_LO_EXPR, "vec_unpack_float_lo_expr", tcc_unary, 1)
1364/* Pack (demote/narrow and merge) the elements of the two input vectors
1365 into the output vector using truncation/saturation.
1366 The elements of the input vectors are twice the size of the elements of the
1367 output vector. This is used to support type demotion. */
1368DEFTREECODE (VEC_PACK_TRUNC_EXPR, "vec_pack_trunc_expr", tcc_binary, 2)
1369DEFTREECODE (VEC_PACK_SAT_EXPR, "vec_pack_sat_expr", tcc_binary, 2)
1371/* Convert floating point values of the two input vectors to integer
1372 and pack (narrow and merge) the elements into the output vector. The
1373 elements of the input vector are twice the size of the elements of
1374 the output vector. */
1375DEFTREECODE (VEC_PACK_FIX_TRUNC_EXPR, "vec_pack_fix_trunc_expr", tcc_binary, 2)
1377/* Widening vector shift left in bits.
1378 Operand 0 is a vector to be shifted with N elements of size S.
1379 Operand 1 is an integer shift amount in bits.
1380 The result of the operation is N elements of size 2*S.
1381 VEC_WIDEN_LSHIFT_HI_EXPR computes the N/2 high results.
1382 VEC_WIDEN_LSHIFT_LO_EXPR computes the N/2 low results.
1383 */
1384DEFTREECODE (VEC_WIDEN_LSHIFT_HI_EXPR, "widen_lshift_hi_expr", tcc_binary, 2)
1385DEFTREECODE (VEC_WIDEN_LSHIFT_LO_EXPR, "widen_lshift_lo_expr", tcc_binary, 2)
1387/* PREDICT_EXPR. Specify hint for branch prediction. The
1389 outcome (0 for not taken and 1 for taken). Once the profile is guessed
1390 all conditional branches leading to execution paths executing the
1391 PREDICT_EXPR will get predicted by the specified predictor. */
1392DEFTREECODE (PREDICT_EXPR, "predict_expr", tcc_expression, 1)
1394/* OPTIMIZATION_NODE. Node to store the optimization options. */
1395DEFTREECODE (OPTIMIZATION_NODE, "optimization_node", tcc_exceptional, 0)
1397/* TARGET_OPTION_NODE. Node to store the target specific options. */
1398DEFTREECODE (TARGET_OPTION_NODE, "target_option_node", tcc_exceptional, 0)
1401 Operand 0 is the expression to be annotated.
1402 Operand 1 is the annotation kind.
1403 Operand 2 is additional data. */
1404DEFTREECODE (ANNOTATE_EXPR, "annotate_expr", tcc_expression, 3)
1407Local variables: