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, 2007, 2008, 2009 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
23 /* For tcc_references, tcc_expression, tcc_comparison, tcc_unary,
24 tcc_binary, and tcc_statement nodes, which use struct tree_exp, the
25 4th element is the number of argument slots to allocate. This
26 determines the size of the tree node object. Other nodes use
27 different structures, and the size is determined by the tree_union
28 member structure; the 4th element should be zero. Languages that
29 define language-specific tcc_exceptional or tcc_constant codes must
30 define the tree_size langhook to say how big they are.
32 These tree codes have been sorted so that the macros in tree.h that
33 check for various tree codes are optimized into range checks. This
34 gives a measurable performance improvement. When adding a new
35 code, consider its placement in relation to the other codes. */
37 /* Any erroneous construct is parsed into a node of this type.
38 This type of node is accepted without complaint in all contexts
39 by later parsing activities, to avoid multiple error messages
41 No fields in these nodes are used except the TREE_CODE. */
42 DEFTREECODE (ERROR_MARK, "error_mark", tcc_exceptional, 0)
44 /* Used to represent a name (such as, in the DECL_NAME of a decl node).
45 Internally it looks like a STRING_CST node.
46 There is only one IDENTIFIER_NODE ever made for any particular name.
47 Use `get_identifier' to get it (or create it, the first time). */
48 DEFTREECODE (IDENTIFIER_NODE, "identifier_node", tcc_exceptional, 0)
50 /* Has the TREE_VALUE and TREE_PURPOSE fields. */
51 /* These nodes are made into lists by chaining through the
52 TREE_CHAIN field. The elements of the list live in the
53 TREE_VALUE fields, while TREE_PURPOSE fields are occasionally
54 used as well to get the effect of Lisp association lists. */
55 DEFTREECODE (TREE_LIST, "tree_list", tcc_exceptional, 0)
57 /* These nodes contain an array of tree nodes. */
58 DEFTREECODE (TREE_VEC, "tree_vec", tcc_exceptional, 0)
60 /* A symbol binding block. These are arranged in a tree,
61 where the BLOCK_SUBBLOCKS field contains a chain of subblocks
62 chained through the BLOCK_CHAIN field.
63 BLOCK_SUPERCONTEXT points to the parent block.
64 For a block which represents the outermost scope of a function, it
65 points to the FUNCTION_DECL node.
66 BLOCK_VARS points to a chain of decl nodes.
67 BLOCK_CHAIN points to the next BLOCK at the same level.
68 BLOCK_ABSTRACT_ORIGIN points to the original (abstract) tree node which
69 this block is an instance of, or else is NULL to indicate that this
70 block is not an instance of anything else. When non-NULL, the value
71 could either point to another BLOCK node or it could point to a
72 FUNCTION_DECL node (e.g. in the case of a block representing the
73 outermost scope of a particular inlining of a function).
74 BLOCK_ABSTRACT is nonzero if the block represents an abstract
75 instance of a block (i.e. one which is nested within an abstract
76 instance of an inline function).
77 TREE_ASM_WRITTEN is nonzero if the block was actually referenced
78 in the generated assembly. */
79 DEFTREECODE (BLOCK, "block", tcc_exceptional, 0)
81 /* Each data type is represented by a tree node whose code is one of
83 /* Each node that represents a data type has a component TYPE_SIZE
84 containing a tree that is an expression for the size in bits.
85 The TYPE_MODE contains the machine mode for values of this type.
86 The TYPE_POINTER_TO field contains a type for a pointer to this type,
87 or zero if no such has been created yet.
88 The TYPE_NEXT_VARIANT field is used to chain together types
89 that are variants made by type modifiers such as "const" and "volatile".
90 The TYPE_MAIN_VARIANT field, in any member of such a chain,
91 points to the start of the chain.
92 The TYPE_NONCOPIED_PARTS field is a list specifying which parts
93 of an object of this type should *not* be copied by assignment.
94 The TREE_VALUE of each is a FIELD_DECL that should not be
95 copied. The TREE_PURPOSE is an initial value for that field when
96 an object of this type is initialized via an INIT_EXPR. It may
97 be NULL if no special value is required. Even the things in this
98 list are copied if the right-hand side of an assignment is known
99 to be a complete object (rather than being, perhaps, a subobject
100 of some other object.) The determination of what constitutes a
101 complete object is done by fixed_type_p.
102 The TYPE_NAME field contains info on the name used in the program
103 for this type (for GDB symbol table output). It is either a
104 TYPE_DECL node, for types that are typedefs, or an IDENTIFIER_NODE
105 in the case of structs, unions or enums that are known with a tag,
106 or zero for types that have no special name.
107 The TYPE_CONTEXT for any sort of type which could have a name or
108 which could have named members (e.g. tagged types in C/C++) will
109 point to the node which represents the scope of the given type, or
110 will be NULL_TREE if the type has "file scope". For most types, this
111 will point to a BLOCK node or a FUNCTION_DECL node, but it could also
112 point to a FUNCTION_TYPE node (for types whose scope is limited to the
113 formal parameter list of some function type specification) or it
114 could point to a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE node
115 (for C++ "member" types).
116 For non-tagged-types, TYPE_CONTEXT need not be set to anything in
117 particular, since any type which is of some type category (e.g.
118 an array type or a function type) which cannot either have a name
119 itself or have named members doesn't really have a "scope" per se.
120 The TREE_CHAIN field is used as a forward-references to names for
121 ENUMERAL_TYPE, RECORD_TYPE, UNION_TYPE, and QUAL_UNION_TYPE nodes;
124 /* The ordering of the following codes is optimized for the checking
125 macros in tree.h. Changing the order will degrade the speed of the
126 compiler. OFFSET_TYPE, ENUMERAL_TYPE, BOOLEAN_TYPE, INTEGER_TYPE,
127 REAL_TYPE, POINTER_TYPE. */
129 /* An offset is a pointer relative to an object.
130 The TREE_TYPE field is the type of the object at the offset.
131 The TYPE_OFFSET_BASETYPE points to the node for the type of object
132 that the offset is relative to. */
133 DEFTREECODE (OFFSET_TYPE, "offset_type", tcc_type, 0)
135 /* C enums. The type node looks just like an INTEGER_TYPE node.
136 The symbols for the values of the enum type are defined by
137 CONST_DECL nodes, but the type does not point to them;
138 however, the TYPE_VALUES is a list in which each element's TREE_PURPOSE
139 is a name and the TREE_VALUE is the value (an INTEGER_CST node). */
140 /* A forward reference `enum foo' when no enum named foo is defined yet
141 has zero (a null pointer) in its TYPE_SIZE. The tag name is in
142 the TYPE_NAME field. If the type is later defined, the normal
143 fields are filled in.
144 RECORD_TYPE, UNION_TYPE, and QUAL_UNION_TYPE forward refs are
145 treated similarly. */
146 DEFTREECODE (ENUMERAL_TYPE, "enumeral_type", tcc_type, 0)
148 /* Boolean type (true or false are the only values). Looks like an
150 DEFTREECODE (BOOLEAN_TYPE, "boolean_type", tcc_type, 0)
152 /* Integer types in all languages, including char in C.
153 Also used for sub-ranges of other discrete types.
154 Has components TYPE_MIN_VALUE, TYPE_MAX_VALUE (expressions, inclusive)
155 and TYPE_PRECISION (number of bits used by this type).
156 In the case of a subrange type in Pascal, the TREE_TYPE
157 of this will point at the supertype (another INTEGER_TYPE,
158 or an ENUMERAL_TYPE or BOOLEAN_TYPE).
159 Otherwise, the TREE_TYPE is zero. */
160 DEFTREECODE (INTEGER_TYPE, "integer_type", tcc_type, 0)
162 /* C's float and double. Different floating types are distinguished
163 by machine mode and by the TYPE_SIZE and the TYPE_PRECISION. */
164 DEFTREECODE (REAL_TYPE, "real_type", tcc_type, 0)
166 /* The ordering of the following codes is optimized for the checking
167 macros in tree.h. Changing the order will degrade the speed of the
168 compiler. POINTER_TYPE, REFERENCE_TYPE. Note that this range
169 overlaps the previous range of ordered types. */
171 /* All pointer-to-x types have code POINTER_TYPE.
172 The TREE_TYPE points to the node for the type pointed to. */
173 DEFTREECODE (POINTER_TYPE, "pointer_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
178 DEFTREECODE (FIXED_POINT_TYPE, "fixed_point_type", tcc_type, 0)
180 /* A reference is like a pointer except that it is coerced
181 automatically to the value it points to. Used in C++. */
182 DEFTREECODE (REFERENCE_TYPE, "reference_type", tcc_type, 0)
184 /* The ordering of the following codes is optimized for the checking
185 macros in tree.h. Changing the order will degrade the speed of the
186 compiler. COMPLEX_TYPE, VECTOR_TYPE, ARRAY_TYPE. */
188 /* Complex number types. The TREE_TYPE field is the data type
189 of the real and imaginary parts. It must be of scalar
190 arithmetic type, not including pointer type. */
191 DEFTREECODE (COMPLEX_TYPE, "complex_type", tcc_type, 0)
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
196 DEFTREECODE (VECTOR_TYPE, "vector_type", tcc_type, 0)
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. */
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 */
212 DEFTREECODE (ARRAY_TYPE, "array_type", tcc_type, 0)
214 /* Struct in C, or record in Pascal. */
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. */
222 DEFTREECODE (RECORD_TYPE, "record_type", tcc_type, 0)
224 /* Union in C. Like a struct, except that the offsets of the fields
226 /* See the comment above, before ENUMERAL_TYPE, for how
227 forward references to union tags are handled in C. */
228 DEFTREECODE (UNION_TYPE, "union_type", tcc_type, 0) /* C union type */
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
234 DEFTREECODE (QUAL_UNION_TYPE, "qual_union_type", tcc_type, 0)
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. */
240 /* The void type in C */
241 DEFTREECODE (VOID_TYPE, "void_type", tcc_type, 0)
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. */
249 DEFTREECODE (FUNCTION_TYPE, "function_type", tcc_type, 0)
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". */
256 DEFTREECODE (METHOD_TYPE, "method_type", tcc_type, 0)
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. */
262 DEFTREECODE (LANG_TYPE, "lang_type", tcc_type, 0)
266 /* First, the constants. */
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 TREE_OVERFLOW.
272 If an INTEGER_CST has TREE_OVERFLOW already set, it is known to be unique.
273 INTEGER_CST nodes are created for the integral types, for pointer
274 types and for vector and float types in some circumstances. */
275 DEFTREECODE (INTEGER_CST, "integer_cst", tcc_constant, 0)
277 /* Contents are in TREE_REAL_CST field. */
278 DEFTREECODE (REAL_CST, "real_cst", tcc_constant, 0)
280 /* Contents are in TREE_FIXED_CST field. */
281 DEFTREECODE (FIXED_CST, "fixed_cst", tcc_constant, 0)
283 /* Contents are in TREE_REALPART and TREE_IMAGPART fields,
284 whose contents are other constant nodes. */
285 DEFTREECODE (COMPLEX_CST, "complex_cst", tcc_constant, 0)
287 /* Contents are in TREE_VECTOR_CST_ELTS field. */
288 DEFTREECODE (VECTOR_CST, "vector_cst", tcc_constant, 0)
290 /* Contents are TREE_STRING_LENGTH and the actual contents of the string. */
291 DEFTREECODE (STRING_CST, "string_cst", tcc_constant, 0)
293 /* Declarations. All references to names are represented as ..._DECL
294 nodes. The decls in one binding context are chained through the
295 TREE_CHAIN field. Each DECL has a DECL_NAME field which contains
296 an IDENTIFIER_NODE. (Some decls, most often labels, may have zero
297 as the DECL_NAME). DECL_CONTEXT points to the node representing
298 the context in which this declaration has its scope. For
299 FIELD_DECLs, this is the RECORD_TYPE, UNION_TYPE, or
300 QUAL_UNION_TYPE node that the field is a member of. For VAR_DECL,
301 PARM_DECL, FUNCTION_DECL, LABEL_DECL, and CONST_DECL nodes, this
302 points to either the FUNCTION_DECL for the containing function, the
303 RECORD_TYPE or UNION_TYPE for the containing type, or NULL_TREE or
304 a TRANSLATION_UNIT_DECL if the given decl has "file scope".
305 DECL_ABSTRACT_ORIGIN, if non-NULL, points to the original (abstract)
306 ..._DECL node of which this decl is an (inlined or template expanded)
308 The TREE_TYPE field holds the data type of the object, when relevant.
309 LABEL_DECLs have no data type. For TYPE_DECL, the TREE_TYPE field
310 contents are the type whose name is being declared.
311 The DECL_ALIGN, DECL_SIZE,
312 and DECL_MODE fields exist in decl nodes just as in type nodes.
313 They are unused in LABEL_DECL, TYPE_DECL and CONST_DECL nodes.
315 DECL_FIELD_BIT_OFFSET holds an integer number of bits offset for
316 the location. DECL_VOFFSET holds an expression for a variable
317 offset; it is to be multiplied by DECL_VOFFSET_UNIT (an integer).
318 These fields are relevant only in FIELD_DECLs and PARM_DECLs.
320 DECL_INITIAL holds the value to initialize a variable to,
321 or the value of a constant. For a function, it holds the body
322 (a node of type BLOCK representing the function's binding contour
323 and whose body contains the function's statements.) For a LABEL_DECL
324 in C, it is a flag, nonzero if the label's definition has been seen.
326 PARM_DECLs use a special field:
327 DECL_ARG_TYPE is the type in which the argument is actually
328 passed, which may be different from its type within the function.
330 FUNCTION_DECLs use four special fields:
331 DECL_ARGUMENTS holds a chain of PARM_DECL nodes for the arguments.
332 DECL_RESULT holds a RESULT_DECL node for the value of a function.
333 The DECL_RTL field is 0 for a function that returns no value.
334 (C functions returning void have zero here.)
335 The TREE_TYPE field is the type in which the result is actually
336 returned. This is usually the same as the return type of the
337 FUNCTION_DECL, but it may be a wider integer type because of
339 DECL_FUNCTION_CODE is a code number that is nonzero for
340 built-in functions. Its value is an enum built_in_function
341 that says which built-in function it is.
343 DECL_SOURCE_FILE holds a filename string and DECL_SOURCE_LINE
344 holds a line number. In some cases these can be the location of
345 a reference, if no definition has been seen.
347 DECL_ABSTRACT is nonzero if the decl represents an abstract instance
348 of a decl (i.e. one which is nested within an abstract instance of a
351 DEFTREECODE (FUNCTION_DECL, "function_decl", tcc_declaration, 0)
352 DEFTREECODE (LABEL_DECL, "label_decl", tcc_declaration, 0)
353 /* The ordering of the following codes is optimized for the checking
354 macros in tree.h. Changing the order will degrade the speed of the
355 compiler. FIELD_DECL, VAR_DECL, CONST_DECL, PARM_DECL,
357 DEFTREECODE (FIELD_DECL, "field_decl", tcc_declaration, 0)
358 DEFTREECODE (VAR_DECL, "var_decl", tcc_declaration, 0)
359 DEFTREECODE (CONST_DECL, "const_decl", tcc_declaration, 0)
360 DEFTREECODE (PARM_DECL, "parm_decl", tcc_declaration, 0)
361 DEFTREECODE (TYPE_DECL, "type_decl", tcc_declaration, 0)
362 DEFTREECODE (RESULT_DECL, "result_decl", tcc_declaration, 0)
364 /* A namespace declaration. Namespaces appear in DECL_CONTEXT of other
365 _DECLs, providing a hierarchy of names. */
366 DEFTREECODE (NAMESPACE_DECL, "namespace_decl", tcc_declaration, 0)
368 /* A declaration import.
369 The C++ FE uses this to represent a using-directive; eg:
370 "using namespace foo".
371 But it could be used to represent any declaration import construct.
372 Whenever a declaration import appears in a lexical block, the BLOCK node
373 representing that lexical block in GIMPLE will contain an IMPORTED_DECL
374 node, linked via BLOCK_VARS accessor of the said BLOCK.
375 For a given NODE which code is IMPORTED_DECL,
376 IMPORTED_DECL_ASSOCIATED_DECL (NODE) accesses the imported declaration. */
377 DEFTREECODE (IMPORTED_DECL, "imported_decl", tcc_declaration, 0)
379 /* A translation unit. This is not technically a declaration, since it
380 can't be looked up, but it's close enough. */
381 DEFTREECODE (TRANSLATION_UNIT_DECL, "translation_unit_decl",\
384 /* References to storage. */
386 /* Value is structure or union component.
387 Operand 0 is the structure or union (an expression).
388 Operand 1 is the field (a node of type FIELD_DECL).
389 Operand 2, if present, is the value of DECL_FIELD_OFFSET, measured
390 in units of DECL_OFFSET_ALIGN / BITS_PER_UNIT. */
391 DEFTREECODE (COMPONENT_REF, "component_ref", tcc_reference, 3)
393 /* Reference to a group of bits within an object. Similar to COMPONENT_REF
394 except the position is given explicitly rather than via a FIELD_DECL.
395 Operand 0 is the structure or union expression;
396 operand 1 is a tree giving the constant number of bits being referenced;
397 operand 2 is a tree giving the constant position of the first referenced bit.
398 The result type width has to match the number of bits referenced.
399 If the result type is integral, its signedness specifies how it is extended
400 to its mode width. */
401 DEFTREECODE (BIT_FIELD_REF, "bit_field_ref", tcc_reference, 3)
403 /* The ordering of the following codes is optimized for the checking
404 macros in tree.h. Changing the order will degrade the speed of the
405 compiler. INDIRECT_REF, ALIGN_INDIRECT_REF, MISALIGNED_INDIRECT_REF. */
407 /* C unary `*' or Pascal `^'. One operand, an expression for a pointer. */
408 DEFTREECODE (INDIRECT_REF, "indirect_ref", tcc_reference, 1)
410 /* Like above, but aligns the referenced address (i.e, if the address
411 in P is not aligned on TYPE_ALIGN boundary, then &(*P) != P). */
412 DEFTREECODE (ALIGN_INDIRECT_REF, "align_indirect_ref", tcc_reference, 1)
414 /* Same as INDIRECT_REF, but also specifies the alignment of the referenced
416 Operand 0 is the referenced address (a pointer);
417 Operand 1 is an INTEGER_CST which represents the alignment of the address,
418 or 0 if the alignment is unknown. */
419 DEFTREECODE (MISALIGNED_INDIRECT_REF, "misaligned_indirect_ref", tcc_reference, 2)
422 Operand 0 is the array; operand 1 is a (single) array index.
423 Operand 2, if present, is a copy of TYPE_MIN_VALUE of the index.
424 Operand 3, if present, is the element size, measured in units of
425 the alignment of the element type. */
426 DEFTREECODE (ARRAY_REF, "array_ref", tcc_reference, 4)
428 /* Likewise, except that the result is a range ("slice") of the array. The
429 starting index of the resulting array is taken from operand 1 and the size
430 of the range is taken from the type of the expression. */
431 DEFTREECODE (ARRAY_RANGE_REF, "array_range_ref", tcc_reference, 4)
433 /* Used to represent lookup of runtime type dependent data. Often this is
434 a reference to a vtable, but it needn't be. Operands are:
435 OBJ_TYPE_REF_EXPR: An expression that evaluates the value to use.
436 OBJ_TYPE_REF_OBJECT: Is the object on whose behalf the lookup is
437 being performed. Through this the optimizers may be able to statically
438 determine the dynamic type of the object.
439 OBJ_TYPE_REF_TOKEN: Something front-end specific used to resolve the
440 reference to something simpler, usually to the address of a DECL.
441 Never touched by the middle-end. Good choices would be either an
442 identifier or a vtable index. */
443 DEFTREECODE (OBJ_TYPE_REF, "obj_type_ref", tcc_expression, 3)
445 /* The exception object from the runtime. */
446 DEFTREECODE (EXC_PTR_EXPR, "exc_ptr_expr", tcc_expression, 0)
448 /* The filter object from the runtime. */
449 DEFTREECODE (FILTER_EXPR, "filter_expr", tcc_expression, 0)
451 /* Constructor: return an aggregate value made from specified components.
452 In C, this is used only for structure and array initializers.
453 The operand is a sequence of component values made out of a VEC of
454 struct constructor_elt.
457 The field INDEX of each constructor_elt is the corresponding index.
458 If the index is a RANGE_EXPR, it is a short-hand for many nodes,
459 one for each index in the range. (If the corresponding field VALUE
460 has side-effects, they are evaluated once for each element. Wrap the
461 value in a SAVE_EXPR if you want to evaluate side effects only once.)
463 For RECORD_TYPE, UNION_TYPE, or QUAL_UNION_TYPE:
464 The field INDEX of each node is a FIELD_DECL. */
465 DEFTREECODE (CONSTRUCTOR, "constructor", tcc_exceptional, 0)
467 /* The expression types are mostly straightforward, with the fourth argument
468 of DEFTREECODE saying how many operands there are.
469 Unless otherwise specified, the operands are expressions and the
470 types of all the operands and the expression must all be the same. */
472 /* Contains two expressions to compute, one followed by the other.
473 the first value is ignored. The second one's value is used. The
474 type of the first expression need not agree with the other types. */
475 DEFTREECODE (COMPOUND_EXPR, "compound_expr", tcc_expression, 2)
477 /* Assignment expression. Operand 0 is the what to set; 1, the new value. */
478 DEFTREECODE (MODIFY_EXPR, "modify_expr", tcc_expression, 2)
480 /* Initialization expression. Operand 0 is the variable to initialize;
481 Operand 1 is the initializer. This differs from MODIFY_EXPR in that any
482 reference to the referent of operand 0 within operand 1 is undefined. */
483 DEFTREECODE (INIT_EXPR, "init_expr", tcc_expression, 2)
485 /* For TARGET_EXPR, operand 0 is the target of an initialization,
486 operand 1 is the initializer for the target, which may be void
487 if simply expanding it initializes the target.
488 operand 2 is the cleanup for this node, if any.
489 operand 3 is the saved initializer after this node has been
490 expanded once; this is so we can re-expand the tree later. */
491 DEFTREECODE (TARGET_EXPR, "target_expr", tcc_expression, 4)
493 /* Conditional expression ( ... ? ... : ... in C).
494 Operand 0 is the condition.
495 Operand 1 is the then-value.
496 Operand 2 is the else-value.
497 Operand 0 may be of any type.
498 Operand 1 must have the same type as the entire expression, unless
499 it unconditionally throws an exception, in which case it should
500 have VOID_TYPE. The same constraints apply to operand 2. The
501 condition in operand 0 must be of integral type.
503 In cfg gimple, if you do not have a selection expression, operands
504 1 and 2 are NULL. The operands are then taken from the cfg edges. */
505 DEFTREECODE (COND_EXPR, "cond_expr", tcc_expression, 3)
507 /* Vector conditional expression. It is like COND_EXPR, but with
510 A = VEC_COND_EXPR ( X < Y, B, C)
515 A[i] = X[i] < Y[i] ? B[i] : C[i];
517 DEFTREECODE (VEC_COND_EXPR, "vec_cond_expr", tcc_expression, 3)
519 /* Declare local variables, including making RTL and allocating space.
520 BIND_EXPR_VARS is a chain of VAR_DECL nodes for the variables.
521 BIND_EXPR_BODY is the body, the expression to be computed using
522 the variables. The value of operand 1 becomes that of the BIND_EXPR.
523 BIND_EXPR_BLOCK is the BLOCK that corresponds to these bindings
524 for debugging purposes. If this BIND_EXPR is actually expanded,
525 that sets the TREE_USED flag in the BLOCK.
527 The BIND_EXPR is not responsible for informing parsers
528 about these variables. If the body is coming from the input file,
529 then the code that creates the BIND_EXPR is also responsible for
530 informing the parser of the variables.
532 If the BIND_EXPR is ever expanded, its TREE_USED flag is set.
533 This tells the code for debugging symbol tables not to ignore the BIND_EXPR.
534 If the BIND_EXPR should be output for debugging but will not be expanded,
535 set the TREE_USED flag by hand.
537 In order for the BIND_EXPR to be known at all, the code that creates it
538 must also install it as a subblock in the tree of BLOCK
539 nodes for the function. */
540 DEFTREECODE (BIND_EXPR, "bind_expr", tcc_expression, 3)
542 /* Function call. CALL_EXPRs are represented by variably-sized expression
543 nodes. There are at least three fixed operands. Operand 0 is an
544 INTEGER_CST node containing the total operand count, the number of
545 arguments plus 3. Operand 1 is the function, while operand 2 is
546 is static chain argument, or NULL. The remaining operands are the
547 arguments to the call. */
548 DEFTREECODE (CALL_EXPR, "call_expr", tcc_vl_exp, 3)
550 /* Specify a value to compute along with its corresponding cleanup.
551 Operand 0 is the cleanup expression.
552 The cleanup is executed by the first enclosing CLEANUP_POINT_EXPR,
553 which must exist. This differs from TRY_CATCH_EXPR in that operand 1
554 is always evaluated when cleanups are run. */
555 DEFTREECODE (WITH_CLEANUP_EXPR, "with_cleanup_expr", tcc_expression, 1)
557 /* Specify a cleanup point.
558 Operand 0 is an expression that may have cleanups. If it does, those
559 cleanups are executed after the expression is expanded.
561 Note that if the expression is a reference to storage, it is forced out
562 of memory before the cleanups are run. This is necessary to handle
563 cases where the cleanups modify the storage referenced; in the
564 expression 't.i', if 't' is a struct with an integer member 'i' and a
565 cleanup which modifies 'i', the value of the expression depends on
566 whether the cleanup is run before or after 't.i' is evaluated. When
567 expand_expr is run on 't.i', it returns a MEM. This is not good enough;
568 the value of 't.i' must be forced out of memory.
570 As a consequence, the operand of a CLEANUP_POINT_EXPR must not have
571 BLKmode, because it will not be forced out of memory. */
572 DEFTREECODE (CLEANUP_POINT_EXPR, "cleanup_point_expr", tcc_expression, 1)
574 /* The following two codes are used in languages that have types where
575 some field in an object of the type contains a value that is used in
576 the computation of another field's offset or size and/or the size of
577 the type. The positions and/or sizes of fields can vary from object
578 to object of the same type or even for one and the same object within
581 Record types with discriminants in Ada or schema types in Pascal are
582 examples of such types. This mechanism is also used to create "fat
583 pointers" for unconstrained array types in Ada; the fat pointer is a
584 structure one of whose fields is a pointer to the actual array type
585 and the other field is a pointer to a template, which is a structure
586 containing the bounds of the array. The bounds in the type pointed
587 to by the first field in the fat pointer refer to the values in the
590 When you wish to construct such a type you need "self-references"
591 that allow you to reference the object having this type from the
592 TYPE node, i.e. without having a variable instantiating this type.
594 Such a "self-references" is done using a PLACEHOLDER_EXPR. This is
595 a node that will later be replaced with the object being referenced.
596 Its type is that of the object and selects which object to use from
597 a chain of references (see below). No other slots are used in the
600 For example, if your type FOO is a RECORD_TYPE with a field BAR,
601 and you need the value of <variable>.BAR to calculate TYPE_SIZE
602 (FOO), just substitute <variable> above with a PLACEHOLDER_EXPR
603 whose TREE_TYPE is FOO. Then construct your COMPONENT_REF with
604 the PLACEHOLDER_EXPR as the first operand (which has the correct
605 type). Later, when the size is needed in the program, the back-end
606 will find this PLACEHOLDER_EXPR and generate code to calculate the
607 actual size at run-time. In the following, we describe how this
610 When we wish to evaluate a size or offset, we check whether it contains a
611 PLACEHOLDER_EXPR. If it does, we call substitute_placeholder_in_expr
612 passing both that tree and an expression within which the object may be
613 found. The latter expression is the object itself in the simple case of
614 an Ada record with discriminant, but it can be the array in the case of an
617 In the latter case, we need the fat pointer, because the bounds of
618 the array can only be accessed from it. However, we rely here on the
619 fact that the expression for the array contains the dereference of
620 the fat pointer that obtained the array pointer. */
622 /* Denotes a record to later be substituted before evaluating this expression.
623 The type of this expression is used to find the record to replace it. */
624 DEFTREECODE (PLACEHOLDER_EXPR, "placeholder_expr", tcc_exceptional, 0)
626 /* Simple arithmetic. */
627 DEFTREECODE (PLUS_EXPR, "plus_expr", tcc_binary, 2)
628 DEFTREECODE (MINUS_EXPR, "minus_expr", tcc_binary, 2)
629 DEFTREECODE (MULT_EXPR, "mult_expr", tcc_binary, 2)
631 /* Pointer addition. The first operand is always a pointer and the
632 second operand is an integer of type sizetype. */
633 DEFTREECODE (POINTER_PLUS_EXPR, "pointer_plus_expr", tcc_binary, 2)
635 /* Division for integer result that rounds the quotient toward zero. */
636 DEFTREECODE (TRUNC_DIV_EXPR, "trunc_div_expr", tcc_binary, 2)
638 /* Division for integer result that rounds the quotient toward infinity. */
639 DEFTREECODE (CEIL_DIV_EXPR, "ceil_div_expr", tcc_binary, 2)
641 /* Division for integer result that rounds toward minus infinity. */
642 DEFTREECODE (FLOOR_DIV_EXPR, "floor_div_expr", tcc_binary, 2)
644 /* Division for integer result that rounds toward nearest integer. */
645 DEFTREECODE (ROUND_DIV_EXPR, "round_div_expr", tcc_binary, 2)
647 /* Four kinds of remainder that go with the four kinds of division. */
648 DEFTREECODE (TRUNC_MOD_EXPR, "trunc_mod_expr", tcc_binary, 2)
649 DEFTREECODE (CEIL_MOD_EXPR, "ceil_mod_expr", tcc_binary, 2)
650 DEFTREECODE (FLOOR_MOD_EXPR, "floor_mod_expr", tcc_binary, 2)
651 DEFTREECODE (ROUND_MOD_EXPR, "round_mod_expr", tcc_binary, 2)
653 /* Division for real result. */
654 DEFTREECODE (RDIV_EXPR, "rdiv_expr", tcc_binary, 2)
656 /* Division which is not supposed to need rounding.
657 Used for pointer subtraction in C. */
658 DEFTREECODE (EXACT_DIV_EXPR, "exact_div_expr", tcc_binary, 2)
660 /* Conversion of real to fixed point by truncation. */
661 DEFTREECODE (FIX_TRUNC_EXPR, "fix_trunc_expr", tcc_unary, 1)
663 /* Conversion of an integer to a real. */
664 DEFTREECODE (FLOAT_EXPR, "float_expr", tcc_unary, 1)
666 /* Unary negation. */
667 DEFTREECODE (NEGATE_EXPR, "negate_expr", tcc_unary, 1)
669 /* Minimum and maximum values. When used with floating point, if both
670 operands are zeros, or if either operand is NaN, then it is unspecified
671 which of the two operands is returned as the result. */
672 DEFTREECODE (MIN_EXPR, "min_expr", tcc_binary, 2)
673 DEFTREECODE (MAX_EXPR, "max_expr", tcc_binary, 2)
675 /* Represents the absolute value of the operand.
677 An ABS_EXPR must have either an INTEGER_TYPE or a REAL_TYPE. The
678 operand of the ABS_EXPR must have the same type. */
679 DEFTREECODE (ABS_EXPR, "abs_expr", tcc_unary, 1)
681 /* Shift operations for shift and rotate.
682 Shift means logical shift if done on an
683 unsigned type, arithmetic shift if done on a signed type.
684 The second operand is the number of bits to
685 shift by; it need not be the same type as the first operand and result.
686 Note that the result is undefined if the second operand is larger
687 than or equal to the first operand's type size.
689 The first operand of a shift can have either an integer or a
690 (non-integer) fixed-point type. We follow the ISO/IEC TR 18037:2004
691 semantics for the latter.
693 Rotates are defined for integer types only. */
694 DEFTREECODE (LSHIFT_EXPR, "lshift_expr", tcc_binary, 2)
695 DEFTREECODE (RSHIFT_EXPR, "rshift_expr", tcc_binary, 2)
696 DEFTREECODE (LROTATE_EXPR, "lrotate_expr", tcc_binary, 2)
697 DEFTREECODE (RROTATE_EXPR, "rrotate_expr", tcc_binary, 2)
699 /* Bitwise operations. Operands have same mode as result. */
700 DEFTREECODE (BIT_IOR_EXPR, "bit_ior_expr", tcc_binary, 2)
701 DEFTREECODE (BIT_XOR_EXPR, "bit_xor_expr", tcc_binary, 2)
702 DEFTREECODE (BIT_AND_EXPR, "bit_and_expr", tcc_binary, 2)
703 DEFTREECODE (BIT_NOT_EXPR, "bit_not_expr", tcc_unary, 1)
705 /* ANDIF and ORIF allow the second operand not to be computed if the
706 value of the expression is determined from the first operand. AND,
707 OR, and XOR always compute the second operand whether its value is
708 needed or not (for side effects). The operand may have
709 BOOLEAN_TYPE or INTEGER_TYPE. In either case, the argument will be
710 either zero or one. For example, a TRUTH_NOT_EXPR will never have
711 an INTEGER_TYPE VAR_DECL as its argument; instead, a NE_EXPR will be
712 used to compare the VAR_DECL to zero, thereby obtaining a node with
713 value zero or one. */
714 DEFTREECODE (TRUTH_ANDIF_EXPR, "truth_andif_expr", tcc_expression, 2)
715 DEFTREECODE (TRUTH_ORIF_EXPR, "truth_orif_expr", tcc_expression, 2)
716 DEFTREECODE (TRUTH_AND_EXPR, "truth_and_expr", tcc_expression, 2)
717 DEFTREECODE (TRUTH_OR_EXPR, "truth_or_expr", tcc_expression, 2)
718 DEFTREECODE (TRUTH_XOR_EXPR, "truth_xor_expr", tcc_expression, 2)
719 DEFTREECODE (TRUTH_NOT_EXPR, "truth_not_expr", tcc_expression, 1)
721 /* Relational operators.
722 `EQ_EXPR' and `NE_EXPR' are allowed for any types.
723 The others are allowed only for integer (or pointer or enumeral)
725 In all cases the operands will have the same type,
726 and the value is always the type used by the language for booleans. */
727 DEFTREECODE (LT_EXPR, "lt_expr", tcc_comparison, 2)
728 DEFTREECODE (LE_EXPR, "le_expr", tcc_comparison, 2)
729 DEFTREECODE (GT_EXPR, "gt_expr", tcc_comparison, 2)
730 DEFTREECODE (GE_EXPR, "ge_expr", tcc_comparison, 2)
731 DEFTREECODE (EQ_EXPR, "eq_expr", tcc_comparison, 2)
732 DEFTREECODE (NE_EXPR, "ne_expr", tcc_comparison, 2)
734 /* Additional relational operators for floating point unordered. */
735 DEFTREECODE (UNORDERED_EXPR, "unordered_expr", tcc_comparison, 2)
736 DEFTREECODE (ORDERED_EXPR, "ordered_expr", tcc_comparison, 2)
738 /* These are equivalent to unordered or ... */
739 DEFTREECODE (UNLT_EXPR, "unlt_expr", tcc_comparison, 2)
740 DEFTREECODE (UNLE_EXPR, "unle_expr", tcc_comparison, 2)
741 DEFTREECODE (UNGT_EXPR, "ungt_expr", tcc_comparison, 2)
742 DEFTREECODE (UNGE_EXPR, "unge_expr", tcc_comparison, 2)
743 DEFTREECODE (UNEQ_EXPR, "uneq_expr", tcc_comparison, 2)
745 /* This is the reverse of uneq_expr. */
746 DEFTREECODE (LTGT_EXPR, "ltgt_expr", tcc_comparison, 2)
748 DEFTREECODE (RANGE_EXPR, "range_expr", tcc_binary, 2)
750 /* Represents a re-association barrier for floating point expressions
751 like explicit parenthesis in fortran. */
752 DEFTREECODE (PAREN_EXPR, "paren_expr", tcc_unary, 1)
754 /* Represents a conversion of type of a value.
755 All conversions, including implicit ones, must be
756 represented by CONVERT_EXPR or NOP_EXPR nodes. */
757 DEFTREECODE (CONVERT_EXPR, "convert_expr", tcc_unary, 1)
759 /* Conversion of a fixed-point value to an integer, a real, or a fixed-point
760 value. Or conversion of a fixed-point value from an integer, a real, or
761 a fixed-point value. */
762 DEFTREECODE (FIXED_CONVERT_EXPR, "fixed_convert_expr", tcc_unary, 1)
764 /* Represents a conversion expected to require no code to be generated. */
765 DEFTREECODE (NOP_EXPR, "nop_expr", tcc_unary, 1)
767 /* Value is same as argument, but guaranteed not an lvalue. */
768 DEFTREECODE (NON_LVALUE_EXPR, "non_lvalue_expr", tcc_unary, 1)
770 /* Represents viewing something of one type as being of a second type.
771 This corresponds to an "Unchecked Conversion" in Ada and roughly to
772 the idiom *(type2 *)&X in C. The only operand is the value to be
773 viewed as being of another type. It is undefined if the type of the
774 input and of the expression have different sizes.
776 This code may also be used within the LHS of a MODIFY_EXPR, in which
777 case no actual data motion may occur. TREE_ADDRESSABLE will be set in
778 this case and GCC must abort if it could not do the operation without
780 DEFTREECODE (VIEW_CONVERT_EXPR, "view_convert_expr", tcc_reference, 1)
782 /* A COMPOUND_LITERAL_EXPR represents a literal that is placed in a DECL. The
783 COMPOUND_LITERAL_EXPR_DECL_EXPR is the a DECL_EXPR containing the decl
784 for the anonymous object represented by the COMPOUND_LITERAL;
785 the DECL_INITIAL of that decl is the CONSTRUCTOR that initializes
786 the compound literal. */
787 DEFTREECODE (COMPOUND_LITERAL_EXPR, "compound_literal_expr", tcc_expression, 1)
789 /* Represents something we computed once and will use multiple times.
790 First operand is that expression. After it is evaluated once, it
791 will be replaced by the temporary variable that holds the value. */
792 DEFTREECODE (SAVE_EXPR, "save_expr", tcc_expression, 1)
794 /* & in C. Value is the address at which the operand's value resides.
795 Operand may have any mode. Result mode is Pmode. */
796 DEFTREECODE (ADDR_EXPR, "addr_expr", tcc_expression, 1)
798 /* Operand0 is a function constant; result is part N of a function
799 descriptor of type ptr_mode. */
800 DEFTREECODE (FDESC_EXPR, "fdesc_expr", tcc_expression, 2)
802 /* Given two real or integer operands of the same type,
803 returns a complex value of the corresponding complex type. */
804 DEFTREECODE (COMPLEX_EXPR, "complex_expr", tcc_binary, 2)
806 /* Complex conjugate of operand. Used only on complex types. */
807 DEFTREECODE (CONJ_EXPR, "conj_expr", tcc_unary, 1)
809 /* Used only on an operand of complex type, these return
810 a value of the corresponding component type. */
811 DEFTREECODE (REALPART_EXPR, "realpart_expr", tcc_reference, 1)
812 DEFTREECODE (IMAGPART_EXPR, "imagpart_expr", tcc_reference, 1)
814 /* Nodes for ++ and -- in C.
815 The second arg is how much to increment or decrement by.
816 For a pointer, it would be the size of the object pointed to. */
817 DEFTREECODE (PREDECREMENT_EXPR, "predecrement_expr", tcc_expression, 2)
818 DEFTREECODE (PREINCREMENT_EXPR, "preincrement_expr", tcc_expression, 2)
819 DEFTREECODE (POSTDECREMENT_EXPR, "postdecrement_expr", tcc_expression, 2)
820 DEFTREECODE (POSTINCREMENT_EXPR, "postincrement_expr", tcc_expression, 2)
822 /* Used to implement `va_arg'. */
823 DEFTREECODE (VA_ARG_EXPR, "va_arg_expr", tcc_expression, 1)
825 /* Evaluate operand 1. If and only if an exception is thrown during
826 the evaluation of operand 1, evaluate operand 2.
828 This differs from TRY_FINALLY_EXPR in that operand 2 is not evaluated
829 on a normal or jump exit, only on an exception. */
830 DEFTREECODE (TRY_CATCH_EXPR, "try_catch_expr", tcc_statement, 2)
832 /* Evaluate the first operand.
833 The second operand is a cleanup expression which is evaluated
834 on any exit (normal, exception, or jump out) from this expression. */
835 DEFTREECODE (TRY_FINALLY_EXPR, "try_finally", tcc_statement, 2)
837 /* These types of expressions have no useful value,
838 and always have side effects. */
840 /* Used to represent a local declaration. The operand is DECL_EXPR_DECL. */
841 DEFTREECODE (DECL_EXPR, "decl_expr", tcc_statement, 1)
843 /* A label definition, encapsulated as a statement.
844 Operand 0 is the LABEL_DECL node for the label that appears here.
845 The type should be void and the value should be ignored. */
846 DEFTREECODE (LABEL_EXPR, "label_expr", tcc_statement, 1)
848 /* GOTO. Operand 0 is a LABEL_DECL node or an expression.
849 The type should be void and the value should be ignored. */
850 DEFTREECODE (GOTO_EXPR, "goto_expr", tcc_statement, 1)
852 /* RETURN. Evaluates operand 0, then returns from the current function.
853 Presumably that operand is an assignment that stores into the
854 RESULT_DECL that hold the value to be returned.
855 The operand may be null.
856 The type should be void and the value should be ignored. */
857 DEFTREECODE (RETURN_EXPR, "return_expr", tcc_statement, 1)
859 /* Exit the inner most loop conditionally. Operand 0 is the condition.
860 The type should be void and the value should be ignored. */
861 DEFTREECODE (EXIT_EXPR, "exit_expr", tcc_statement, 1)
863 /* A loop. Operand 0 is the body of the loop.
864 It must contain an EXIT_EXPR or is an infinite loop.
865 The type should be void and the value should be ignored. */
866 DEFTREECODE (LOOP_EXPR, "loop_expr", tcc_statement, 1)
868 /* Switch expression.
870 TREE_TYPE is the original type of the condition, before any
871 language required type conversions. It may be NULL, in which case
872 the original type and final types are assumed to be the same.
874 Operand 0 is the expression used to perform the branch,
875 Operand 1 is the body of the switch, which probably contains
876 CASE_LABEL_EXPRs. It may also be NULL, in which case operand 2
878 Operand 2 is either NULL_TREE or a TREE_VEC of the CASE_LABEL_EXPRs
880 DEFTREECODE (SWITCH_EXPR, "switch_expr", tcc_statement, 3)
882 /* Used to represent a case label. The operands are CASE_LOW and
883 CASE_HIGH, respectively. If CASE_LOW is NULL_TREE, the label is a
884 'default' label. If CASE_HIGH is NULL_TREE, the label is a normal case
885 label. CASE_LABEL is the corresponding LABEL_DECL. */
886 DEFTREECODE (CASE_LABEL_EXPR, "case_label_expr", tcc_statement, 3)
888 /* RESX. Resume execution after an exception. Operand 0 is a
889 number indicating the exception region that is being left. */
890 DEFTREECODE (RESX_EXPR, "resx_expr", tcc_statement, 1)
892 /* Used to represent an inline assembly statement. ASM_STRING returns a
893 STRING_CST for the instruction (e.g., "mov x, y"). ASM_OUTPUTS,
894 ASM_INPUTS, and ASM_CLOBBERS represent the outputs, inputs, and clobbers
895 for the statement. */
896 DEFTREECODE (ASM_EXPR, "asm_expr", tcc_statement, 4)
898 /* Variable references for SSA analysis. New SSA names are created every
899 time a variable is assigned a new value. The SSA builder uses SSA_NAME
900 nodes to implement SSA versioning. */
901 DEFTREECODE (SSA_NAME, "ssa_name", tcc_exceptional, 0)
903 /* Used to represent a typed exception handler. CATCH_TYPES is the type (or
904 list of types) handled, and CATCH_BODY is the code for the handler. */
905 DEFTREECODE (CATCH_EXPR, "catch_expr", tcc_statement, 2)
907 /* Used to represent an exception specification. EH_FILTER_TYPES is a list
908 of allowed types, and EH_FILTER_FAILURE is an expression to evaluate on
909 failure. EH_FILTER_MUST_NOT_THROW controls which range type to use when
911 DEFTREECODE (EH_FILTER_EXPR, "eh_filter_expr", tcc_statement, 2)
913 /* Indicates a change in the dynamic type of a memory location. This
914 has no value and generates no executable code. It is only used for
915 type based alias analysis. This is generated by C++ placement new.
916 CHANGE_DYNAMIC_TYPE_NEW_TYPE, the first operand, is the new type.
917 CHANGE_DYNAMIC_TYPE_LOCATION, the second operand, is the location
918 whose type is being changed. */
919 DEFTREECODE (CHANGE_DYNAMIC_TYPE_EXPR, "change_dynamic_type_expr",
922 /* Node used for describing a property that is known at compile
924 DEFTREECODE (SCEV_KNOWN, "scev_known", tcc_expression, 0)
926 /* Node used for describing a property that is not known at compile
928 DEFTREECODE (SCEV_NOT_KNOWN, "scev_not_known", tcc_expression, 0)
930 /* Polynomial chains of recurrences.
931 Under the form: cr = {CHREC_LEFT (cr), +, CHREC_RIGHT (cr)}. */
932 DEFTREECODE (POLYNOMIAL_CHREC, "polynomial_chrec", tcc_expression, 3)
934 /* Used to chain children of container statements together.
935 Use the interface in tree-iterator.h to access this node. */
936 DEFTREECODE (STATEMENT_LIST, "statement_list", tcc_exceptional, 0)
938 /* Predicate assertion. Artificial expression generated by the optimizers
939 to keep track of predicate values. This expression may only appear on
940 the RHS of assignments.
942 Given X = ASSERT_EXPR <Y, EXPR>, the optimizers can infer
946 2- EXPR is a conditional expression and is known to be true.
948 Valid and to be expected forms of conditional expressions are
949 valid GIMPLE conditional expressions (as defined by is_gimple_condexpr)
950 and conditional expressions with the first operand being a
951 PLUS_EXPR with a variable possibly wrapped in a NOP_EXPR first
952 operand and an integer constant second operand.
954 The type of the expression is the same as Y. */
955 DEFTREECODE (ASSERT_EXPR, "assert_expr", tcc_expression, 2)
957 /* Base class information. Holds information about a class as a
958 baseclass of itself or another class. */
959 DEFTREECODE (TREE_BINFO, "tree_binfo", tcc_exceptional, 0)
961 /* Records the size for an expression of variable size type. This is
962 for use in contexts in which we are accessing the entire object,
963 such as for a function call, or block copy.
964 Operand 0 is the real expression.
965 Operand 1 is the size of the type in the expression. */
966 DEFTREECODE (WITH_SIZE_EXPR, "with_size_expr", tcc_expression, 2)
968 /* Extract elements from two input vectors Operand 0 and Operand 1
969 size VS, according to the offset OFF defined by Operand 2 as
971 If OFF > 0, the last VS - OFF elements of vector OP0 are concatenated to
972 the first OFF elements of the vector OP1.
973 If OFF == 0, then the returned vector is OP1.
974 On different targets OFF may take different forms; It can be an address, in
975 which case its low log2(VS)-1 bits define the offset, or it can be a mask
976 generated by the builtin targetm.vectorize.mask_for_load_builtin_decl. */
977 DEFTREECODE (REALIGN_LOAD_EXPR, "realign_load", tcc_expression, 3)
979 /* Low-level memory addressing. Operands are SYMBOL (static or global
980 variable), BASE (register), INDEX (register), STEP (integer constant),
981 OFFSET (integer constant). Corresponding address is
982 SYMBOL + BASE + STEP * INDEX + OFFSET. Only variations and values valid on
983 the target are allowed.
985 The type of STEP, INDEX and OFFSET is sizetype. The type of BASE is
986 sizetype or a pointer type (if SYMBOL is NULL).
988 The sixth argument is the reference to the original memory access, which
989 is preserved for the purposes of the RTL alias analysis. */
991 DEFTREECODE (TARGET_MEM_REF, "target_mem_ref", tcc_reference, 6)
993 /* The ordering of the codes between OMP_PARALLEL and OMP_CRITICAL is
994 exposed to TREE_RANGE_CHECK. */
995 /* OpenMP - #pragma omp parallel [clause1 ... clauseN]
996 Operand 0: OMP_PARALLEL_BODY: Code to be executed by all threads.
997 Operand 1: OMP_PARALLEL_CLAUSES: List of clauses. */
999 DEFTREECODE (OMP_PARALLEL, "omp_parallel", tcc_statement, 2)
1001 /* OpenMP - #pragma omp task [clause1 ... clauseN]
1002 Operand 0: OMP_TASK_BODY: Code to be executed by all threads.
1003 Operand 1: OMP_TASK_CLAUSES: List of clauses. */
1005 DEFTREECODE (OMP_TASK, "omp_task", tcc_statement, 2)
1007 /* OpenMP - #pragma omp for [clause1 ... clauseN]
1008 Operand 0: OMP_FOR_BODY: Loop body.
1009 Operand 1: OMP_FOR_CLAUSES: List of clauses.
1010 Operand 2: OMP_FOR_INIT: Initialization code of the form
1012 Operand 3: OMP_FOR_COND: Loop conditional expression of the form
1013 VAR { <, >, <=, >= } N2.
1014 Operand 4: OMP_FOR_INCR: Loop index increment of the form
1015 VAR { +=, -= } INCR.
1016 Operand 5: OMP_FOR_PRE_BODY: Filled by the gimplifier with things
1017 from INIT, COND, and INCR that are technically part of the
1018 OMP_FOR structured block, but are evaluated before the loop
1021 VAR must be an integer or pointer variable, which is implicitly thread
1022 private. N1, N2 and INCR are required to be loop invariant integer
1023 expressions that are evaluated without any synchronization.
1024 The evaluation order, frequency of evaluation and side-effects are
1025 unspecified by the standard. */
1026 DEFTREECODE (OMP_FOR, "omp_for", tcc_statement, 6)
1028 /* OpenMP - #pragma omp sections [clause1 ... clauseN]
1029 Operand 0: OMP_SECTIONS_BODY: Sections body.
1030 Operand 1: OMP_SECTIONS_CLAUSES: List of clauses. */
1031 DEFTREECODE (OMP_SECTIONS, "omp_sections", tcc_statement, 2)
1033 /* OpenMP - #pragma omp single
1034 Operand 0: OMP_SINGLE_BODY: Single section body.
1035 Operand 1: OMP_SINGLE_CLAUSES: List of clauses. */
1036 DEFTREECODE (OMP_SINGLE, "omp_single", tcc_statement, 2)
1038 /* OpenMP - #pragma omp section
1039 Operand 0: OMP_SECTION_BODY: Section body. */
1040 DEFTREECODE (OMP_SECTION, "omp_section", tcc_statement, 1)
1042 /* OpenMP - #pragma omp master
1043 Operand 0: OMP_MASTER_BODY: Master section body. */
1044 DEFTREECODE (OMP_MASTER, "omp_master", tcc_statement, 1)
1046 /* OpenMP - #pragma omp ordered
1047 Operand 0: OMP_ORDERED_BODY: Master section body. */
1048 DEFTREECODE (OMP_ORDERED, "omp_ordered", tcc_statement, 1)
1050 /* OpenMP - #pragma omp critical [name]
1051 Operand 0: OMP_CRITICAL_BODY: Critical section body.
1052 Operand 1: OMP_CRITICAL_NAME: Identifier for critical section. */
1053 DEFTREECODE (OMP_CRITICAL, "omp_critical", tcc_statement, 2)
1055 /* OpenMP - #pragma omp atomic
1056 Operand 0: The address at which the atomic operation is to be performed.
1057 This address should be stabilized with save_expr.
1058 Operand 1: The expression to evaluate. When the old value of the object
1059 at the address is used in the expression, it should appear as if
1060 build_fold_indirect_ref of the address. */
1061 DEFTREECODE (OMP_ATOMIC, "omp_atomic", tcc_statement, 2)
1063 /* OpenMP clauses. */
1064 DEFTREECODE (OMP_CLAUSE, "omp_clause", tcc_exceptional, 0)
1066 /* Reduction operations.
1067 Operations that take a vector of elements and "reduce" it to a scalar
1068 result (e.g. summing the elements of the vector, finding the minimum over
1069 the vector elements, etc).
1070 Operand 0 is a vector; the first element in the vector has the result.
1071 Operand 1 is a vector. */
1072 DEFTREECODE (REDUC_MAX_EXPR, "reduc_max_expr", tcc_unary, 1)
1073 DEFTREECODE (REDUC_MIN_EXPR, "reduc_min_expr", tcc_unary, 1)
1074 DEFTREECODE (REDUC_PLUS_EXPR, "reduc_plus_expr", tcc_unary, 1)
1076 /* Widening dot-product.
1077 The first two arguments are of type t1.
1078 The third argument and the result are of type t2, such that t2 is at least
1079 twice the size of t1. DOT_PROD_EXPR(arg1,arg2,arg3) is equivalent to:
1080 tmp = WIDEN_MULT_EXPR(arg1, arg2);
1081 arg3 = PLUS_EXPR (tmp, arg3);
1083 tmp = WIDEN_MULT_EXPR(arg1, arg2);
1084 arg3 = WIDEN_SUM_EXPR (tmp, arg3); */
1085 DEFTREECODE (DOT_PROD_EXPR, "dot_prod_expr", tcc_expression, 3)
1087 /* Widening summation.
1088 The first argument is of type t1.
1089 The second argument is of type t2, such that t2 is at least twice
1090 the size of t1. The type of the entire expression is also t2.
1091 WIDEN_SUM_EXPR is equivalent to first widening (promoting)
1092 the first argument from type t1 to type t2, and then summing it
1093 with the second argument. */
1094 DEFTREECODE (WIDEN_SUM_EXPR, "widen_sum_expr", tcc_binary, 2)
1096 /* Widening multiplication.
1097 The two arguments are of type t1.
1098 The result is of type t2, such that t2 is at least twice
1099 the size of t1. WIDEN_MULT_EXPR is equivalent to first widening (promoting)
1100 the arguments from type t1 to type t2, and then multiplying them. */
1101 DEFTREECODE (WIDEN_MULT_EXPR, "widen_mult_expr", tcc_binary, 2)
1103 /* Whole vector left/right shift in bits.
1104 Operand 0 is a vector to be shifted.
1105 Operand 1 is an integer shift amount in bits. */
1106 DEFTREECODE (VEC_LSHIFT_EXPR, "vec_lshift_expr", tcc_binary, 2)
1107 DEFTREECODE (VEC_RSHIFT_EXPR, "vec_rshift_expr", tcc_binary, 2)
1109 /* Widening vector multiplication.
1110 The two operands are vectors with N elements of size S. Multiplying the
1111 elements of the two vectors will result in N products of size 2*S.
1112 VEC_WIDEN_MULT_HI_EXPR computes the N/2 high products.
1113 VEC_WIDEN_MULT_LO_EXPR computes the N/2 low products. */
1114 DEFTREECODE (VEC_WIDEN_MULT_HI_EXPR, "widen_mult_hi_expr", tcc_binary, 2)
1115 DEFTREECODE (VEC_WIDEN_MULT_LO_EXPR, "widen_mult_lo_expr", tcc_binary, 2)
1117 /* Unpack (extract and promote/widen) the high/low elements of the input
1118 vector into the output vector. The input vector has twice as many
1119 elements as the output vector, that are half the size of the elements
1120 of the output vector. This is used to support type promotion. */
1121 DEFTREECODE (VEC_UNPACK_HI_EXPR, "vec_unpack_hi_expr", tcc_unary, 1)
1122 DEFTREECODE (VEC_UNPACK_LO_EXPR, "vec_unpack_lo_expr", tcc_unary, 1)
1124 /* Unpack (extract) the high/low elements of the input vector, convert
1125 fixed point values to floating point and widen elements into the
1126 output vector. The input vector has twice as many elements as the output
1127 vector, that are half the size of the elements of the output vector. */
1128 DEFTREECODE (VEC_UNPACK_FLOAT_HI_EXPR, "vec_unpack_float_hi_expr", tcc_unary, 1)
1129 DEFTREECODE (VEC_UNPACK_FLOAT_LO_EXPR, "vec_unpack_float_lo_expr", tcc_unary, 1)
1131 /* Pack (demote/narrow and merge) the elements of the two input vectors
1132 into the output vector using truncation/saturation.
1133 The elements of the input vectors are twice the size of the elements of the
1134 output vector. This is used to support type demotion. */
1135 DEFTREECODE (VEC_PACK_TRUNC_EXPR, "vec_pack_trunc_expr", tcc_binary, 2)
1136 DEFTREECODE (VEC_PACK_SAT_EXPR, "vec_pack_sat_expr", tcc_binary, 2)
1138 /* Convert floating point values of the two input vectors to integer
1139 and pack (narrow and merge) the elements into the output vector. The
1140 elements of the input vector are twice the size of the elements of
1141 the output vector. */
1142 DEFTREECODE (VEC_PACK_FIX_TRUNC_EXPR, "vec_pack_fix_trunc_expr", tcc_binary, 2)
1144 /* Extract even/odd fields from vectors. */
1145 DEFTREECODE (VEC_EXTRACT_EVEN_EXPR, "vec_extracteven_expr", tcc_binary, 2)
1146 DEFTREECODE (VEC_EXTRACT_ODD_EXPR, "vec_extractodd_expr", tcc_binary, 2)
1148 /* Merge input vectors interleaving their fields. */
1149 DEFTREECODE (VEC_INTERLEAVE_HIGH_EXPR, "vec_interleavehigh_expr", tcc_binary, 2)
1150 DEFTREECODE (VEC_INTERLEAVE_LOW_EXPR, "vec_interleavelow_expr", tcc_binary, 2)
1152 /* PREDICT_EXPR. Specify hint for branch prediction. The
1153 PREDICT_EXPR_PREDICTOR specify predictor and PREDICT_EXPR_OUTCOME the
1154 outcome (0 for not taken and 1 for taken). Once the profile is guessed
1155 all conditional branches leading to execution paths executing the
1156 PREDICT_EXPR will get predicted by the specified predictor. */
1157 DEFTREECODE (PREDICT_EXPR, "predict_expr", tcc_expression, 1)
1159 /* OPTIMIZATION_NODE. Node to store the optimization options. */
1160 DEFTREECODE (OPTIMIZATION_NODE, "optimization_node", tcc_exceptional, 0)
1162 /* TARGET_OPTION_NODE. Node to store the target specific options. */
1163 DEFTREECODE (TARGET_OPTION_NODE, "target_option_node", tcc_exceptional, 0)