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, 2010 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_NAME field contains info on the name used in the program
93 for this type (for GDB symbol table output). It is either a
94 TYPE_DECL node, for types that are typedefs, or an IDENTIFIER_NODE
95 in the case of structs, unions or enums that are known with a tag,
96 or zero for types that have no special name.
97 The TYPE_CONTEXT for any sort of type which could have a name or
98 which could have named members (e.g. tagged types in C/C++) will
99 point to the node which represents the scope of the given type, or
100 will be NULL_TREE if the type has "file scope". For most types, this
101 will point to a BLOCK node or a FUNCTION_DECL node, but it could also
102 point to a FUNCTION_TYPE node (for types whose scope is limited to the
103 formal parameter list of some function type specification) or it
104 could point to a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE node
105 (for C++ "member" types).
106 For non-tagged-types, TYPE_CONTEXT need not be set to anything in
107 particular, since any type which is of some type category (e.g.
108 an array type or a function type) which cannot either have a name
109 itself or have named members doesn't really have a
"scope" per se.
110 The TREE_CHAIN field is used as a forward
-references to names for
111 ENUMERAL_TYPE
, RECORD_TYPE
, UNION_TYPE
, and QUAL_UNION_TYPE nodes
;
114 /* The ordering of the following codes is optimized for the checking
115 macros in tree.h. Changing the order will degrade the speed of the
116 compiler. OFFSET_TYPE
, ENUMERAL_TYPE
, BOOLEAN_TYPE
, INTEGER_TYPE
,
117 REAL_TYPE
, POINTER_TYPE.
*/
119 /* An offset is a pointer relative to an object.
120 The TREE_TYPE field is the type of the object at the offset.
121 The TYPE_OFFSET_BASETYPE points to the node for the type of object
122 that the offset is relative to.
*/
123 DEFTREECODE (OFFSET_TYPE
, "offset_type", tcc_type
, 0)
125 /* C enums. The type node looks just like an INTEGER_TYPE node.
126 The symbols for the values of the enum type are defined by
127 CONST_DECL nodes
, but the type does not point to them
;
128 however
, the TYPE_VALUES is a list in which each element
's TREE_PURPOSE
129 is a name and the TREE_VALUE is the value (an INTEGER_CST node). */
130 /* A forward reference `enum foo' when no enum named foo is defined yet
131 has
zero (a null pointer
) in its TYPE_SIZE. The tag name is in
132 the TYPE_NAME field. If the type is later defined
, the normal
133 fields are filled in.
134 RECORD_TYPE
, UNION_TYPE
, and QUAL_UNION_TYPE forward refs are
135 treated similarly.
*/
136 DEFTREECODE (ENUMERAL_TYPE
, "enumeral_type", tcc_type
, 0)
138 /* Boolean
type (true or false are the only values
). Looks like an
140 DEFTREECODE (BOOLEAN_TYPE
, "boolean_type", tcc_type
, 0)
142 /* Integer types in all languages
, including char in C.
143 Also used for sub
-ranges of other discrete types.
144 Has components TYPE_MIN_VALUE
, TYPE_MAX_VALUE (expressions
, inclusive
)
145 and
TYPE_PRECISION (number of bits used by this type
).
146 In the case of a subrange type in Pascal
, the TREE_TYPE
147 of this will point at the
supertype (another INTEGER_TYPE
,
148 or an ENUMERAL_TYPE or BOOLEAN_TYPE
).
149 Otherwise
, the TREE_TYPE is zero.
*/
150 DEFTREECODE (INTEGER_TYPE
, "integer_type", tcc_type
, 0)
152 /* C
's float and double. Different floating types are distinguished
153 by machine mode and by the TYPE_SIZE and the TYPE_PRECISION. */
154 DEFTREECODE (REAL_TYPE, "real_type", tcc_type, 0)
156 /* The ordering of the following codes is optimized for the checking
157 macros in tree.h. Changing the order will degrade the speed of the
158 compiler. POINTER_TYPE, REFERENCE_TYPE. Note that this range
159 overlaps the previous range of ordered types. */
161 /* All pointer-to-x types have code POINTER_TYPE.
162 The TREE_TYPE points to the node for the type pointed to. */
163 DEFTREECODE (POINTER_TYPE, "pointer_type", tcc_type, 0)
165 /* A reference is like a pointer except that it is coerced
166 automatically to the value it points to. Used in C++. */
167 DEFTREECODE (REFERENCE_TYPE, "reference_type", tcc_type, 0)
169 /* The C++ decltype(nullptr) type. */
170 DEFTREECODE (NULLPTR_TYPE, "nullptr_type", tcc_type, 0)
172 /* _Fract and _Accum types in Embedded-C. Different fixed-point types
173 are distinguished by machine mode and by the TYPE_SIZE and the
175 DEFTREECODE (FIXED_POINT_TYPE, "fixed_point_type", tcc_type, 0)
177 /* The ordering of the following codes is optimized for the checking
178 macros in tree.h. Changing the order will degrade the speed of the
179 compiler. COMPLEX_TYPE, VECTOR_TYPE, ARRAY_TYPE. */
181 /* Complex number types. The TREE_TYPE field is the data type
182 of the real and imaginary parts. It must be of scalar
183 arithmetic type, not including pointer type. */
184 DEFTREECODE (COMPLEX_TYPE, "complex_type", tcc_type, 0)
186 /* Vector types. The TREE_TYPE field is the data type of the vector
187 elements. The TYPE_PRECISION field is the number of subparts of
189 DEFTREECODE (VECTOR_TYPE, "vector_type", tcc_type, 0)
191 /* The ordering of the following codes is optimized for the checking
192 macros in tree.h. Changing the order will degrade the speed of the
193 compiler. ARRAY_TYPE, RECORD_TYPE, UNION_TYPE, QUAL_UNION_TYPE.
194 Note that this range overlaps the previous range. */
196 /* Types of arrays. Special fields:
197 TREE_TYPE Type of an array element.
198 TYPE_DOMAIN Type to index by.
199 Its range of values specifies the array length.
200 The field TYPE_POINTER_TO (TREE_TYPE (array_type)) is always nonzero
201 and holds the type to coerce a value of that array type to in C.
202 TYPE_STRING_FLAG indicates a string (in contrast to an array of chars)
203 in languages (such as Chill) that make a distinction. */
204 /* Array types in C or Pascal */
205 DEFTREECODE (ARRAY_TYPE, "array_type", tcc_type, 0)
207 /* Struct in C, or record in Pascal. */
209 TYPE_FIELDS chain of FIELD_DECLs for the fields of the struct,
210 and VAR_DECLs, TYPE_DECLs and CONST_DECLs for record-scope variables,
211 types and enumerators.
212 A few may need to be added for Pascal. */
213 /* See the comment above, before ENUMERAL_TYPE, for how
214 forward references to struct tags are handled in C. */
215 DEFTREECODE (RECORD_TYPE, "record_type", tcc_type, 0)
217 /* Union in C. Like a struct, except that the offsets of the fields
219 /* See the comment above, before ENUMERAL_TYPE, for how
220 forward references to union tags are handled in C. */
221 DEFTREECODE (UNION_TYPE, "union_type", tcc_type, 0) /* C union type */
223 /* Similar to UNION_TYPE, except that the expressions in DECL_QUALIFIER
224 in each FIELD_DECL determine what the union contains. The first
225 field whose DECL_QUALIFIER expression is true is deemed to occupy
227 DEFTREECODE (QUAL_UNION_TYPE, "qual_union_type", tcc_type, 0)
229 /* The ordering of the following codes is optimized for the checking
230 macros in tree.h. Changing the order will degrade the speed of the
231 compiler. VOID_TYPE, FUNCTION_TYPE, METHOD_TYPE. */
233 /* The void type in C */
234 DEFTREECODE (VOID_TYPE, "void_type", tcc_type, 0)
236 /* Type of functions. Special fields:
237 TREE_TYPE type of value returned.
238 TYPE_ARG_TYPES list of types of arguments expected.
239 this list is made of TREE_LIST nodes.
240 Types of "Procedures" in languages where they are different from functions
241 have code FUNCTION_TYPE also, but then TREE_TYPE is zero or void type. */
242 DEFTREECODE (FUNCTION_TYPE, "function_type", tcc_type, 0)
244 /* METHOD_TYPE is the type of a function which takes an extra first
245 argument for "self", which is not present in the declared argument list.
246 The TREE_TYPE is the return type of the method. The TYPE_METHOD_BASETYPE
247 is the type of "self". TYPE_ARG_TYPES is the real argument list, which
248 includes the hidden argument for "self". */
249 DEFTREECODE (METHOD_TYPE, "method_type", tcc_type, 0)
251 /* This is a language-specific kind of type.
252 Its meaning is defined by the language front end.
253 layout_type does not know how to lay this out,
254 so the front-end must do so manually. */
255 DEFTREECODE (LANG_TYPE, "lang_type", tcc_type, 0)
259 /* First, the constants. */
261 /* Contents are in TREE_INT_CST_LOW and TREE_INT_CST_HIGH fields,
262 32 bits each, giving us a 64 bit constant capability. INTEGER_CST
263 nodes can be shared, and therefore should be considered read only.
264 They should be copied, before setting a flag such as TREE_OVERFLOW.
265 If an INTEGER_CST has TREE_OVERFLOW already set, it is known to be unique.
266 INTEGER_CST nodes are created for the integral types, for pointer
267 types and for vector and float types in some circumstances. */
268 DEFTREECODE (INTEGER_CST, "integer_cst", tcc_constant, 0)
270 /* Contents are in TREE_REAL_CST field. */
271 DEFTREECODE (REAL_CST, "real_cst", tcc_constant, 0)
273 /* Contents are in TREE_FIXED_CST field. */
274 DEFTREECODE (FIXED_CST, "fixed_cst", tcc_constant, 0)
276 /* Contents are in TREE_REALPART and TREE_IMAGPART fields,
277 whose contents are other constant nodes. */
278 DEFTREECODE (COMPLEX_CST, "complex_cst", tcc_constant, 0)
280 /* Contents are in TREE_VECTOR_CST_ELTS field. */
281 DEFTREECODE (VECTOR_CST, "vector_cst", tcc_constant, 0)
283 /* Contents are TREE_STRING_LENGTH and the actual contents of the string. */
284 DEFTREECODE (STRING_CST, "string_cst", tcc_constant, 0)
286 /* Declarations. All references to names are represented as ..._DECL
287 nodes. The decls in one binding context are chained through the
288 TREE_CHAIN field. Each DECL has a DECL_NAME field which contains
289 an IDENTIFIER_NODE. (Some decls, most often labels, may have zero
290 as the DECL_NAME). DECL_CONTEXT points to the node representing
291 the context in which this declaration has its scope. For
292 FIELD_DECLs, this is the RECORD_TYPE, UNION_TYPE, or
293 QUAL_UNION_TYPE node that the field is a member of. For VAR_DECL,
294 PARM_DECL, FUNCTION_DECL, LABEL_DECL, and CONST_DECL nodes, this
295 points to either the FUNCTION_DECL for the containing function, the
296 RECORD_TYPE or UNION_TYPE for the containing type, or NULL_TREE or
297 a TRANSLATION_UNIT_DECL if the given decl has "file scope".
298 DECL_ABSTRACT_ORIGIN, if non-NULL, points to the original (abstract)
299 ..._DECL node of which this decl is an (inlined or template expanded)
301 The TREE_TYPE field holds the data type of the object, when relevant.
302 LABEL_DECLs have no data type. For TYPE_DECL, the TREE_TYPE field
303 contents are the type whose name is being declared.
304 The DECL_ALIGN, DECL_SIZE,
305 and DECL_MODE fields exist in decl nodes just as in type nodes.
306 They are unused in LABEL_DECL, TYPE_DECL and CONST_DECL nodes.
308 DECL_FIELD_BIT_OFFSET holds an integer number of bits offset for
309 the location. DECL_VOFFSET holds an expression for a variable
310 offset; it is to be multiplied by DECL_VOFFSET_UNIT (an integer).
311 These fields are relevant only in FIELD_DECLs and PARM_DECLs.
313 DECL_INITIAL holds the value to initialize a variable to,
314 or the value of a constant. For a function, it holds the body
315 (a node of type BLOCK representing the function's binding contour
316 and whose body contains the function
's statements.) For a LABEL_DECL
317 in C, it is a flag, nonzero if the label's definition has been seen.
319 PARM_DECLs use a special field
:
320 DECL_ARG_TYPE is the type in which the argument is actually
321 passed
, which may be different from its type within the function.
323 FUNCTION_DECLs use four special fields
:
324 DECL_ARGUMENTS holds a chain of PARM_DECL nodes for the arguments.
325 DECL_RESULT holds a RESULT_DECL node for the value of a function.
326 The DECL_RTL field is
0 for a function that returns no value.
327 (C functions returning void have zero here.
)
328 The TREE_TYPE field is the type in which the result is actually
329 returned. This is usually the same as the return type of the
330 FUNCTION_DECL
, but it may be a wider integer type because of
332 DECL_FUNCTION_CODE is a code number that is nonzero for
333 built
-in functions. Its value is an enum built_in_function
334 that says which built
-in function it is.
336 DECL_SOURCE_FILE holds a filename string and DECL_SOURCE_LINE
337 holds a line number. In some cases these can be the location of
338 a reference
, if no definition has been seen.
340 DECL_ABSTRACT is nonzero if the decl represents an abstract instance
341 of a
decl (i.e. one which is nested within an abstract instance of a
344 DEFTREECODE (FUNCTION_DECL
, "function_decl", tcc_declaration
, 0)
345 DEFTREECODE (LABEL_DECL
, "label_decl", tcc_declaration
, 0)
346 /* The ordering of the following codes is optimized for the checking
347 macros in tree.h. Changing the order will degrade the speed of the
348 compiler. FIELD_DECL
, VAR_DECL
, CONST_DECL
, PARM_DECL
,
350 DEFTREECODE (FIELD_DECL
, "field_decl", tcc_declaration
, 0)
351 DEFTREECODE (VAR_DECL
, "var_decl", tcc_declaration
, 0)
352 DEFTREECODE (CONST_DECL
, "const_decl", tcc_declaration
, 0)
353 DEFTREECODE (PARM_DECL
, "parm_decl", tcc_declaration
, 0)
354 DEFTREECODE (TYPE_DECL
, "type_decl", tcc_declaration
, 0)
355 DEFTREECODE (RESULT_DECL
, "result_decl", tcc_declaration
, 0)
357 /* A
"declaration" of a debug temporary. It should only appear in
359 DEFTREECODE (DEBUG_EXPR_DECL
, "debug_expr_decl", tcc_declaration
, 0)
361 /* A namespace declaration. Namespaces appear in DECL_CONTEXT of other
362 _DECLs
, providing a hierarchy of names.
*/
363 DEFTREECODE (NAMESPACE_DECL
, "namespace_decl", tcc_declaration
, 0)
365 /* A declaration import.
366 The C
++ FE uses this to represent a using
-directive
; eg
:
367 "using namespace foo".
368 But it could be used to represent any declaration import construct.
369 Whenever a declaration import appears in a lexical block
, the BLOCK node
370 representing that lexical block in GIMPLE will contain an IMPORTED_DECL
371 node
, linked via BLOCK_VARS accessor of the said BLOCK.
372 For a given NODE which code is IMPORTED_DECL
,
373 IMPORTED_DECL_ASSOCIATED_DECL (NODE
) accesses the imported declaration.
*/
374 DEFTREECODE (IMPORTED_DECL
, "imported_decl", tcc_declaration
, 0)
376 /* A translation unit. This is not technically a declaration
, since it
377 can
't be looked up, but it's close enough.
*/
378 DEFTREECODE (TRANSLATION_UNIT_DECL
, "translation_unit_decl",\
381 /* References to storage.
*/
383 /* The ordering of the following codes is optimized for the classification
384 in handled_component_p. Keep them in a consecutive group.
*/
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 /* Used only on an operand of complex type
, these return
404 a value of the corresponding component type.
*/
405 DEFTREECODE (REALPART_EXPR
, "realpart_expr", tcc_reference
, 1)
406 DEFTREECODE (IMAGPART_EXPR
, "imagpart_expr", tcc_reference
, 1)
409 Operand
0 is the array
; operand
1 is
a (single
) array index.
410 Operand
2, if present
, is a copy of TYPE_MIN_VALUE of the index.
411 Operand
3, if present
, is the element size
, measured in units of
412 the alignment of the element type.
*/
413 DEFTREECODE (ARRAY_REF
, "array_ref", tcc_reference
, 4)
415 /* Likewise
, except that the result is a
range ("slice") of the array. The
416 starting index of the resulting array is taken from operand
1 and the size
417 of the range is taken from the type of the expression.
*/
418 DEFTREECODE (ARRAY_RANGE_REF
, "array_range_ref", tcc_reference
, 4)
420 /* C unary `
*' or Pascal `^'. One operand
, an expression for a pointer.
*/
421 DEFTREECODE (INDIRECT_REF
, "indirect_ref", tcc_reference
, 1)
423 /* Used to represent lookup in a virtual method table which is dependent on
424 the runtime type of an object. Operands are
:
425 OBJ_TYPE_REF_EXPR
: An expression that evaluates the value to use.
426 OBJ_TYPE_REF_OBJECT
: Is the object on whose behalf the lookup is
427 being performed. Through this the optimizers may be able to statically
428 determine the dynamic type of the object.
429 OBJ_TYPE_REF_TOKEN
: An integer index to the virtual method table.
*/
430 DEFTREECODE (OBJ_TYPE_REF
, "obj_type_ref", tcc_expression
, 3)
432 /* Constructor
: return an aggregate value made from specified components.
433 In C
, this is used only for structure and array initializers.
434 The operand is a sequence of component values made out of a VEC of
435 struct constructor_elt.
438 The field INDEX of each constructor_elt is the corresponding index.
439 If the index is a RANGE_EXPR
, it is a short
-hand for many nodes
,
440 one for each index in the range.
(If the corresponding field VALUE
441 has side
-effects
, they are evaluated once for each element. Wrap the
442 value in a SAVE_EXPR if you want to evaluate side effects only once.
)
444 For RECORD_TYPE
, UNION_TYPE
, or QUAL_UNION_TYPE
:
445 The field INDEX of each node is a FIELD_DECL.
*/
446 DEFTREECODE (CONSTRUCTOR
, "constructor", tcc_exceptional
, 0)
448 /* The expression types are mostly straightforward
, with the fourth argument
449 of DEFTREECODE saying how many operands there are.
450 Unless otherwise specified
, the operands are expressions and the
451 types of all the operands and the expression must all be the same.
*/
453 /* Contains two expressions to compute
, one followed by the other.
454 the first value is ignored. The second one
's value is used. The
455 type of the first expression need not agree with the other types. */
456 DEFTREECODE (COMPOUND_EXPR, "compound_expr", tcc_expression, 2)
458 /* Assignment expression. Operand 0 is the what to set; 1, the new value. */
459 DEFTREECODE (MODIFY_EXPR, "modify_expr", tcc_expression, 2)
461 /* Initialization expression. Operand 0 is the variable to initialize;
462 Operand 1 is the initializer. This differs from MODIFY_EXPR in that any
463 reference to the referent of operand 0 within operand 1 is undefined. */
464 DEFTREECODE (INIT_EXPR, "init_expr", tcc_expression, 2)
466 /* For TARGET_EXPR, operand 0 is the target of an initialization,
467 operand 1 is the initializer for the target, which may be void
468 if simply expanding it initializes the target.
469 operand 2 is the cleanup for this node, if any.
470 operand 3 is the saved initializer after this node has been
471 expanded once; this is so we can re-expand the tree later. */
472 DEFTREECODE (TARGET_EXPR, "target_expr", tcc_expression, 4)
474 /* Conditional expression ( ... ? ... : ... in C).
475 Operand 0 is the condition.
476 Operand 1 is the then-value.
477 Operand 2 is the else-value.
478 Operand 0 may be of any type.
479 Operand 1 must have the same type as the entire expression, unless
480 it unconditionally throws an exception, in which case it should
481 have VOID_TYPE. The same constraints apply to operand 2. The
482 condition in operand 0 must be of integral type.
484 In cfg gimple, if you do not have a selection expression, operands
485 1 and 2 are NULL. The operands are then taken from the cfg edges. */
486 DEFTREECODE (COND_EXPR, "cond_expr", tcc_expression, 3)
488 /* Vector conditional expression. It is like COND_EXPR, but with
491 A = VEC_COND_EXPR ( X < Y, B, C)
496 A[i] = X[i] < Y[i] ? B[i] : C[i];
498 DEFTREECODE (VEC_COND_EXPR, "vec_cond_expr", tcc_expression, 3)
500 /* Vector shuffle expression. A = VEC_SHUFFLE_EXPR<v0, v1, mask>
503 foreach i in length (mask):
504 A = mask[i] < length (v0) ? v0[mask[i]] : v1[mask[i] - length (mask)]
506 V0 and V1 are vectors of the same type. MASK is an integer-typed
507 vector. The number of MASK elements must be the same with the
508 number of elements in V0 and V1. The size of the inner type
509 of the MASK and of the V0 and V1 must be the same.
511 DEFTREECODE (VEC_SHUFFLE_EXPR, "vec_shuffle_expr", tcc_expression, 3)
513 /* Declare local variables, including making RTL and allocating space.
514 BIND_EXPR_VARS is a chain of VAR_DECL nodes for the variables.
515 BIND_EXPR_BODY is the body, the expression to be computed using
516 the variables. The value of operand 1 becomes that of the BIND_EXPR.
517 BIND_EXPR_BLOCK is the BLOCK that corresponds to these bindings
518 for debugging purposes. If this BIND_EXPR is actually expanded,
519 that sets the TREE_USED flag in the BLOCK.
521 The BIND_EXPR is not responsible for informing parsers
522 about these variables. If the body is coming from the input file,
523 then the code that creates the BIND_EXPR is also responsible for
524 informing the parser of the variables.
526 If the BIND_EXPR is ever expanded, its TREE_USED flag is set.
527 This tells the code for debugging symbol tables not to ignore the BIND_EXPR.
528 If the BIND_EXPR should be output for debugging but will not be expanded,
529 set the TREE_USED flag by hand.
531 In order for the BIND_EXPR to be known at all, the code that creates it
532 must also install it as a subblock in the tree of BLOCK
533 nodes for the function. */
534 DEFTREECODE (BIND_EXPR, "bind_expr", tcc_expression, 3)
536 /* Function call. CALL_EXPRs are represented by variably-sized expression
537 nodes. There are at least three fixed operands. Operand 0 is an
538 INTEGER_CST node containing the total operand count, the number of
539 arguments plus 3. Operand 1 is the function, while operand 2 is
540 is static chain argument, or NULL. The remaining operands are the
541 arguments to the call. */
542 DEFTREECODE (CALL_EXPR, "call_expr", tcc_vl_exp, 3)
544 /* Specify a value to compute along with its corresponding cleanup.
545 Operand 0 is the cleanup expression.
546 The cleanup is executed by the first enclosing CLEANUP_POINT_EXPR,
547 which must exist. This differs from TRY_CATCH_EXPR in that operand 1
548 is always evaluated when cleanups are run. */
549 DEFTREECODE (WITH_CLEANUP_EXPR, "with_cleanup_expr", tcc_expression, 1)
551 /* Specify a cleanup point.
552 Operand 0 is an expression that may have cleanups. If it does, those
553 cleanups are executed after the expression is expanded.
555 Note that if the expression is a reference to storage, it is forced out
556 of memory before the cleanups are run. This is necessary to handle
557 cases where the cleanups modify the storage referenced; in the
558 expression 't.i
', if 't
' is a struct with an integer member 'i
' and a
559 cleanup which modifies 'i
', the value of the expression depends on
560 whether the cleanup is run before or after 't.i
' is evaluated. When
561 expand_expr is run on 't.i
', it returns a MEM. This is not good enough;
562 the value of 't.i
' must be forced out of memory.
564 As a consequence, the operand of a CLEANUP_POINT_EXPR must not have
565 BLKmode, because it will not be forced out of memory. */
566 DEFTREECODE (CLEANUP_POINT_EXPR, "cleanup_point_expr", tcc_expression, 1)
568 /* The following code is used in languages that have types where some
569 field in an object of the type contains a value that is used in the
570 computation of another field's offset or size and
/or the size of the
571 type. The positions and
/or sizes of fields can vary from object to
572 object of the same type or even for one and the same object within
575 Record types with discriminants in Ada or schema types in Pascal are
576 examples of such types. This mechanism is also used to create
"fat
577 pointers" for unconstrained array types in Ada
; the fat pointer is a
578 structure one of whose fields is a pointer to the actual array type
579 and the other field is a pointer to a template
, which is a structure
580 containing the bounds of the array. The bounds in the type pointed
581 to by the first field in the fat pointer refer to the values in the
584 When you wish to construct such a type you need
"self-references"
585 that allow you to reference the object having this type from the
586 TYPE node
, i.e. without having a variable instantiating this type.
588 Such a
"self-references" is done using a PLACEHOLDER_EXPR. This is
589 a node that will later be replaced with the object being referenced.
590 Its type is that of the object and selects which object to use from
591 a chain of
references (see below
). No other slots are used in the
594 For example
, if your type FOO is a RECORD_TYPE with a field BAR
,
595 and you need the value of
<variable
>.BAR to calculate TYPE_SIZE
596 (FOO
), just substitute
<variable
> above with a PLACEHOLDER_EXPR
597 whose TREE_TYPE is FOO. Then construct your COMPONENT_REF with
598 the PLACEHOLDER_EXPR as the first
operand (which has the correct
599 type
). Later
, when the size is needed in the program
, the back
-end
600 will find this PLACEHOLDER_EXPR and generate code to calculate the
601 actual size at run
-time. In the following
, we describe how this
604 When we wish to evaluate a size or offset
, we check whether it contains a
605 PLACEHOLDER_EXPR. If it does
, we call substitute_placeholder_in_expr
606 passing both that tree and an expression within which the object may be
607 found. The latter expression is the object itself in the simple case of
608 an Ada record with discriminant
, but it can be the array in the case of an
611 In the latter case
, we need the fat pointer
, because the bounds of
612 the array can only be accessed from it. However
, we rely here on the
613 fact that the expression for the array contains the dereference of
614 the fat pointer that obtained the array pointer.
*/
616 /* Denotes a record to later be substituted before evaluating this expression.
617 The type of this expression is used to find the record to replace it.
*/
618 DEFTREECODE (PLACEHOLDER_EXPR
, "placeholder_expr", tcc_exceptional
, 0)
620 /* Simple arithmetic.
*/
621 DEFTREECODE (PLUS_EXPR
, "plus_expr", tcc_binary
, 2)
622 DEFTREECODE (MINUS_EXPR
, "minus_expr", tcc_binary
, 2)
623 DEFTREECODE (MULT_EXPR
, "mult_expr", tcc_binary
, 2)
625 /* Pointer addition. The first operand is always a pointer and the
626 second operand is an integer of type sizetype.
*/
627 DEFTREECODE (POINTER_PLUS_EXPR
, "pointer_plus_expr", tcc_binary
, 2)
629 /* Division for integer result that rounds the quotient toward zero.
*/
630 DEFTREECODE (TRUNC_DIV_EXPR
, "trunc_div_expr", tcc_binary
, 2)
632 /* Division for integer result that rounds the quotient toward infinity.
*/
633 DEFTREECODE (CEIL_DIV_EXPR
, "ceil_div_expr", tcc_binary
, 2)
635 /* Division for integer result that rounds toward minus infinity.
*/
636 DEFTREECODE (FLOOR_DIV_EXPR
, "floor_div_expr", tcc_binary
, 2)
638 /* Division for integer result that rounds toward nearest integer.
*/
639 DEFTREECODE (ROUND_DIV_EXPR
, "round_div_expr", tcc_binary
, 2)
641 /* Four kinds of remainder that go with the four kinds of division.
*/
642 DEFTREECODE (TRUNC_MOD_EXPR
, "trunc_mod_expr", tcc_binary
, 2)
643 DEFTREECODE (CEIL_MOD_EXPR
, "ceil_mod_expr", tcc_binary
, 2)
644 DEFTREECODE (FLOOR_MOD_EXPR
, "floor_mod_expr", tcc_binary
, 2)
645 DEFTREECODE (ROUND_MOD_EXPR
, "round_mod_expr", tcc_binary
, 2)
647 /* Division for real result.
*/
648 DEFTREECODE (RDIV_EXPR
, "rdiv_expr", tcc_binary
, 2)
650 /* Division which is not supposed to need rounding.
651 Used for pointer subtraction in C.
*/
652 DEFTREECODE (EXACT_DIV_EXPR
, "exact_div_expr", tcc_binary
, 2)
654 /* Conversion of real to fixed point by truncation.
*/
655 DEFTREECODE (FIX_TRUNC_EXPR
, "fix_trunc_expr", tcc_unary
, 1)
657 /* Conversion of an integer to a real.
*/
658 DEFTREECODE (FLOAT_EXPR
, "float_expr", tcc_unary
, 1)
660 /* Unary negation.
*/
661 DEFTREECODE (NEGATE_EXPR
, "negate_expr", tcc_unary
, 1)
663 /* Minimum and maximum values. When used with floating point
, if both
664 operands are zeros
, or if either operand is NaN
, then it is unspecified
665 which of the two operands is returned as the result.
*/
666 DEFTREECODE (MIN_EXPR
, "min_expr", tcc_binary
, 2)
667 DEFTREECODE (MAX_EXPR
, "max_expr", tcc_binary
, 2)
669 /* Represents the absolute value of the operand.
671 An ABS_EXPR must have either an INTEGER_TYPE or a REAL_TYPE. The
672 operand of the ABS_EXPR must have the same type.
*/
673 DEFTREECODE (ABS_EXPR
, "abs_expr", tcc_unary
, 1)
675 /* Shift operations for shift and rotate.
676 Shift means logical shift if done on an
677 unsigned type
, arithmetic shift if done on a signed type.
678 The second operand is the number of bits to
679 shift by
; it need not be the same type as the first operand and result.
680 Note that the result is undefined if the second operand is larger
681 than or equal to the first operand
's type size.
683 The first operand of a shift can have either an integer or a
684 (non-integer) fixed-point type. We follow the ISO/IEC TR 18037:2004
685 semantics for the latter.
687 Rotates are defined for integer types only. */
688 DEFTREECODE (LSHIFT_EXPR, "lshift_expr", tcc_binary, 2)
689 DEFTREECODE (RSHIFT_EXPR, "rshift_expr", tcc_binary, 2)
690 DEFTREECODE (LROTATE_EXPR, "lrotate_expr", tcc_binary, 2)
691 DEFTREECODE (RROTATE_EXPR, "rrotate_expr", tcc_binary, 2)
693 /* Bitwise operations. Operands have same mode as result. */
694 DEFTREECODE (BIT_IOR_EXPR, "bit_ior_expr", tcc_binary, 2)
695 DEFTREECODE (BIT_XOR_EXPR, "bit_xor_expr", tcc_binary, 2)
696 DEFTREECODE (BIT_AND_EXPR, "bit_and_expr", tcc_binary, 2)
697 DEFTREECODE (BIT_NOT_EXPR, "bit_not_expr", tcc_unary, 1)
699 /* ANDIF and ORIF allow the second operand not to be computed if the
700 value of the expression is determined from the first operand. AND,
701 OR, and XOR always compute the second operand whether its value is
702 needed or not (for side effects). The operand may have
703 BOOLEAN_TYPE or INTEGER_TYPE. In either case, the argument will be
704 either zero or one. For example, a TRUTH_NOT_EXPR will never have
705 an INTEGER_TYPE VAR_DECL as its argument; instead, a NE_EXPR will be
706 used to compare the VAR_DECL to zero, thereby obtaining a node with
707 value zero or one. */
708 DEFTREECODE (TRUTH_ANDIF_EXPR, "truth_andif_expr", tcc_expression, 2)
709 DEFTREECODE (TRUTH_ORIF_EXPR, "truth_orif_expr", tcc_expression, 2)
710 DEFTREECODE (TRUTH_AND_EXPR, "truth_and_expr", tcc_expression, 2)
711 DEFTREECODE (TRUTH_OR_EXPR, "truth_or_expr", tcc_expression, 2)
712 DEFTREECODE (TRUTH_XOR_EXPR, "truth_xor_expr", tcc_expression, 2)
713 DEFTREECODE (TRUTH_NOT_EXPR, "truth_not_expr", tcc_expression, 1)
715 /* Relational operators.
716 `EQ_EXPR' and `NE_EXPR
' are allowed for any types.
717 The others are allowed only for integer (or pointer or enumeral)
719 In all cases the operands will have the same type,
720 and the value is either the type used by the language for booleans
721 or an integer vector type of the same size and with the same number
722 of elements as the comparison operands. True for a vector of
723 comparison results has all bits set while false is equal to zero. */
724 DEFTREECODE (LT_EXPR, "lt_expr", tcc_comparison, 2)
725 DEFTREECODE (LE_EXPR, "le_expr", tcc_comparison, 2)
726 DEFTREECODE (GT_EXPR, "gt_expr", tcc_comparison, 2)
727 DEFTREECODE (GE_EXPR, "ge_expr", tcc_comparison, 2)
728 DEFTREECODE (EQ_EXPR, "eq_expr", tcc_comparison, 2)
729 DEFTREECODE (NE_EXPR, "ne_expr", tcc_comparison, 2)
731 /* Additional relational operators for floating point unordered. */
732 DEFTREECODE (UNORDERED_EXPR, "unordered_expr", tcc_comparison, 2)
733 DEFTREECODE (ORDERED_EXPR, "ordered_expr", tcc_comparison, 2)
735 /* These are equivalent to unordered or ... */
736 DEFTREECODE (UNLT_EXPR, "unlt_expr", tcc_comparison, 2)
737 DEFTREECODE (UNLE_EXPR, "unle_expr", tcc_comparison, 2)
738 DEFTREECODE (UNGT_EXPR, "ungt_expr", tcc_comparison, 2)
739 DEFTREECODE (UNGE_EXPR, "unge_expr", tcc_comparison, 2)
740 DEFTREECODE (UNEQ_EXPR, "uneq_expr", tcc_comparison, 2)
742 /* This is the reverse of uneq_expr. */
743 DEFTREECODE (LTGT_EXPR, "ltgt_expr", tcc_comparison, 2)
745 DEFTREECODE (RANGE_EXPR, "range_expr", tcc_binary, 2)
747 /* Represents a re-association barrier for floating point expressions
748 like explicit parenthesis in fortran. */
749 DEFTREECODE (PAREN_EXPR, "paren_expr", tcc_unary, 1)
751 /* Represents a conversion of type of a value.
752 All conversions, including implicit ones, must be
753 represented by CONVERT_EXPR or NOP_EXPR nodes. */
754 DEFTREECODE (CONVERT_EXPR, "convert_expr", tcc_unary, 1)
756 /* Conversion of a pointer value to a pointer to a different
758 DEFTREECODE (ADDR_SPACE_CONVERT_EXPR, "addr_space_convert_expr", tcc_unary, 1)
760 /* Conversion of a fixed-point value to an integer, a real, or a fixed-point
761 value. Or conversion of a fixed-point value from an integer, a real, or
762 a fixed-point value. */
763 DEFTREECODE (FIXED_CONVERT_EXPR, "fixed_convert_expr", tcc_unary, 1)
765 /* Represents a conversion expected to require no code to be generated. */
766 DEFTREECODE (NOP_EXPR, "nop_expr", tcc_unary, 1)
768 /* Value is same as argument, but guaranteed not an lvalue. */
769 DEFTREECODE (NON_LVALUE_EXPR, "non_lvalue_expr", tcc_unary, 1)
771 /* Represents viewing something of one type as being of a second type.
772 This corresponds to an "Unchecked Conversion" in Ada and roughly to
773 the idiom *(type2 *)&X in C. The only operand is the value to be
774 viewed as being of another type. It is undefined if the type of the
775 input and of the expression have different sizes.
777 This code may also be used within the LHS of a MODIFY_EXPR, in which
778 case no actual data motion may occur. TREE_ADDRESSABLE will be set in
779 this case and GCC must abort if it could not do the operation without
781 DEFTREECODE (VIEW_CONVERT_EXPR, "view_convert_expr", tcc_reference, 1)
783 /* A COMPOUND_LITERAL_EXPR represents a literal that is placed in a DECL. The
784 COMPOUND_LITERAL_EXPR_DECL_EXPR is the a DECL_EXPR containing the decl
785 for the anonymous object represented by the COMPOUND_LITERAL;
786 the DECL_INITIAL of that decl is the CONSTRUCTOR that initializes
787 the compound literal. */
788 DEFTREECODE (COMPOUND_LITERAL_EXPR, "compound_literal_expr", tcc_expression, 1)
790 /* Represents something we computed once and will use multiple times.
791 First operand is that expression. After it is evaluated once, it
792 will be replaced by the temporary variable that holds the value. */
793 DEFTREECODE (SAVE_EXPR, "save_expr", tcc_expression, 1)
795 /* & in C. Value is the address at which the operand's value resides.
796 Operand may have any mode. Result mode is Pmode.
*/
797 DEFTREECODE (ADDR_EXPR
, "addr_expr", tcc_expression
, 1)
799 /* Operand0 is a function constant
; result is part N of a function
800 descriptor of type ptr_mode.
*/
801 DEFTREECODE (FDESC_EXPR
, "fdesc_expr", tcc_expression
, 2)
803 /* Given two real or integer operands of the same type
,
804 returns a complex value of the corresponding complex type.
*/
805 DEFTREECODE (COMPLEX_EXPR
, "complex_expr", tcc_binary
, 2)
807 /* Complex conjugate of operand. Used only on complex types.
*/
808 DEFTREECODE (CONJ_EXPR
, "conj_expr", tcc_unary
, 1)
810 /* Nodes for
++ and
-- in C.
811 The second arg is how much to increment or decrement by.
812 For a pointer
, it would be the size of the object pointed to.
*/
813 DEFTREECODE (PREDECREMENT_EXPR
, "predecrement_expr", tcc_expression
, 2)
814 DEFTREECODE (PREINCREMENT_EXPR
, "preincrement_expr", tcc_expression
, 2)
815 DEFTREECODE (POSTDECREMENT_EXPR
, "postdecrement_expr", tcc_expression
, 2)
816 DEFTREECODE (POSTINCREMENT_EXPR
, "postincrement_expr", tcc_expression
, 2)
818 /* Used to implement `va_arg
'. */
819 DEFTREECODE (VA_ARG_EXPR, "va_arg_expr", tcc_expression, 1)
821 /* Evaluate operand 1. If and only if an exception is thrown during
822 the evaluation of operand 1, evaluate operand 2.
824 This differs from TRY_FINALLY_EXPR in that operand 2 is not evaluated
825 on a normal or jump exit, only on an exception. */
826 DEFTREECODE (TRY_CATCH_EXPR, "try_catch_expr", tcc_statement, 2)
828 /* Evaluate the first operand.
829 The second operand is a cleanup expression which is evaluated
830 on any exit (normal, exception, or jump out) from this expression. */
831 DEFTREECODE (TRY_FINALLY_EXPR, "try_finally", tcc_statement, 2)
833 /* These types of expressions have no useful value,
834 and always have side effects. */
836 /* Used to represent a local declaration. The operand is DECL_EXPR_DECL. */
837 DEFTREECODE (DECL_EXPR, "decl_expr", tcc_statement, 1)
839 /* A label definition, encapsulated as a statement.
840 Operand 0 is the LABEL_DECL node for the label that appears here.
841 The type should be void and the value should be ignored. */
842 DEFTREECODE (LABEL_EXPR, "label_expr", tcc_statement, 1)
844 /* GOTO. Operand 0 is a LABEL_DECL node or an expression.
845 The type should be void and the value should be ignored. */
846 DEFTREECODE (GOTO_EXPR, "goto_expr", tcc_statement, 1)
848 /* RETURN. Evaluates operand 0, then returns from the current function.
849 Presumably that operand is an assignment that stores into the
850 RESULT_DECL that hold the value to be returned.
851 The operand may be null.
852 The type should be void and the value should be ignored. */
853 DEFTREECODE (RETURN_EXPR, "return_expr", tcc_statement, 1)
855 /* Exit the inner most loop conditionally. Operand 0 is the condition.
856 The type should be void and the value should be ignored. */
857 DEFTREECODE (EXIT_EXPR, "exit_expr", tcc_statement, 1)
859 /* A loop. Operand 0 is the body of the loop.
860 It must contain an EXIT_EXPR or is an infinite loop.
861 The type should be void and the value should be ignored. */
862 DEFTREECODE (LOOP_EXPR, "loop_expr", tcc_statement, 1)
864 /* Switch expression.
866 TREE_TYPE is the original type of the condition, before any
867 language required type conversions. It may be NULL, in which case
868 the original type and final types are assumed to be the same.
870 Operand 0 is the expression used to perform the branch,
871 Operand 1 is the body of the switch, which probably contains
872 CASE_LABEL_EXPRs. It may also be NULL, in which case operand 2
874 Operand 2 is either NULL_TREE or a TREE_VEC of the CASE_LABEL_EXPRs
876 DEFTREECODE (SWITCH_EXPR, "switch_expr", tcc_statement, 3)
878 /* Used to represent a case label. The operands are CASE_LOW and
879 CASE_HIGH, respectively. If CASE_LOW is NULL_TREE, the label is a
880 'default
' label. If CASE_HIGH is NULL_TREE, the label is a normal case
881 label. CASE_LABEL is the corresponding LABEL_DECL. */
882 DEFTREECODE (CASE_LABEL_EXPR, "case_label_expr", tcc_statement, 4)
884 /* Used to represent an inline assembly statement. ASM_STRING returns a
885 STRING_CST for the instruction (e.g., "mov x, y"). ASM_OUTPUTS,
886 ASM_INPUTS, and ASM_CLOBBERS represent the outputs, inputs, and clobbers
887 for the statement. ASM_LABELS, if present, indicates various destinations
888 for the asm; labels cannot be combined with outputs. */
889 DEFTREECODE (ASM_EXPR, "asm_expr", tcc_statement, 5)
891 /* Variable references for SSA analysis. New SSA names are created every
892 time a variable is assigned a new value. The SSA builder uses SSA_NAME
893 nodes to implement SSA versioning. */
894 DEFTREECODE (SSA_NAME, "ssa_name", tcc_exceptional, 0)
896 /* Used to represent a typed exception handler. CATCH_TYPES is the type (or
897 list of types) handled, and CATCH_BODY is the code for the handler. */
898 DEFTREECODE (CATCH_EXPR, "catch_expr", tcc_statement, 2)
900 /* Used to represent an exception specification. EH_FILTER_TYPES is a list
901 of allowed types, and EH_FILTER_FAILURE is an expression to evaluate on
902 failure. EH_FILTER_MUST_NOT_THROW controls which range type to use when
904 DEFTREECODE (EH_FILTER_EXPR, "eh_filter_expr", tcc_statement, 2)
906 /* Node used for describing a property that is known at compile
908 DEFTREECODE (SCEV_KNOWN, "scev_known", tcc_expression, 0)
910 /* Node used for describing a property that is not known at compile
912 DEFTREECODE (SCEV_NOT_KNOWN, "scev_not_known", tcc_expression, 0)
914 /* Polynomial chains of recurrences.
915 Under the form: cr = {CHREC_LEFT (cr), +, CHREC_RIGHT (cr)}. */
916 DEFTREECODE (POLYNOMIAL_CHREC, "polynomial_chrec", tcc_expression, 3)
918 /* Used to chain children of container statements together.
919 Use the interface in tree-iterator.h to access this node. */
920 DEFTREECODE (STATEMENT_LIST, "statement_list", tcc_exceptional, 0)
922 /* Predicate assertion. Artificial expression generated by the optimizers
923 to keep track of predicate values. This expression may only appear on
924 the RHS of assignments.
926 Given X = ASSERT_EXPR <Y, EXPR>, the optimizers can infer
930 2- EXPR is a conditional expression and is known to be true.
932 Valid and to be expected forms of conditional expressions are
933 valid GIMPLE conditional expressions (as defined by is_gimple_condexpr)
934 and conditional expressions with the first operand being a
935 PLUS_EXPR with a variable possibly wrapped in a NOP_EXPR first
936 operand and an integer constant second operand.
938 The type of the expression is the same as Y. */
939 DEFTREECODE (ASSERT_EXPR, "assert_expr", tcc_expression, 2)
941 /* Base class information. Holds information about a class as a
942 baseclass of itself or another class. */
943 DEFTREECODE (TREE_BINFO, "tree_binfo", tcc_exceptional, 0)
945 /* Records the size for an expression of variable size type. This is
946 for use in contexts in which we are accessing the entire object,
947 such as for a function call, or block copy.
948 Operand 0 is the real expression.
949 Operand 1 is the size of the type in the expression. */
950 DEFTREECODE (WITH_SIZE_EXPR, "with_size_expr", tcc_expression, 2)
952 /* Extract elements from two input vectors Operand 0 and Operand 1
953 size VS, according to the offset OFF defined by Operand 2 as
955 If OFF > 0, the last VS - OFF elements of vector OP0 are concatenated to
956 the first OFF elements of the vector OP1.
957 If OFF == 0, then the returned vector is OP1.
958 On different targets OFF may take different forms; It can be an address, in
959 which case its low log2(VS)-1 bits define the offset, or it can be a mask
960 generated by the builtin targetm.vectorize.mask_for_load_builtin_decl. */
961 DEFTREECODE (REALIGN_LOAD_EXPR, "realign_load", tcc_expression, 3)
963 /* Low-level memory addressing. Operands are BASE (address of static or
964 global variable or register), OFFSET (integer constant),
965 INDEX (register), STEP (integer constant), INDEX2 (register),
966 The corresponding address is BASE + STEP * INDEX + INDEX2 + OFFSET.
967 Only variations and values valid on the target are allowed.
969 The type of STEP, INDEX and INDEX2 is sizetype.
971 The type of BASE is a pointer type. If BASE is not an address of
972 a static or global variable INDEX2 will be NULL.
974 The type of OFFSET is a pointer type and determines TBAA the same as
975 the constant offset operand in MEM_REF. */
977 DEFTREECODE (TARGET_MEM_REF, "target_mem_ref", tcc_reference, 5)
979 /* Memory addressing. Operands are a pointer and a tree constant integer
980 byte offset of the pointer type that when dereferenced yields the
981 type of the base object the pointer points into and which is used for
983 The type of the MEM_REF is the type the bytes at the memory location
985 MEM_REF <p, c> is equivalent to ((typeof(c))p)->x... where x... is a
986 chain of component references offsetting p by c. */
987 DEFTREECODE (MEM_REF, "mem_ref", tcc_reference, 2)
989 /* The ordering of the codes between OMP_PARALLEL and OMP_CRITICAL is
990 exposed to TREE_RANGE_CHECK. */
991 /* OpenMP - #pragma omp parallel [clause1 ... clauseN]
992 Operand 0: OMP_PARALLEL_BODY: Code to be executed by all threads.
993 Operand 1: OMP_PARALLEL_CLAUSES: List of clauses. */
995 DEFTREECODE (OMP_PARALLEL, "omp_parallel", tcc_statement, 2)
997 /* OpenMP - #pragma omp task [clause1 ... clauseN]
998 Operand 0: OMP_TASK_BODY: Code to be executed by all threads.
999 Operand 1: OMP_TASK_CLAUSES: List of clauses. */
1001 DEFTREECODE (OMP_TASK, "omp_task", tcc_statement, 2)
1003 /* OpenMP - #pragma omp for [clause1 ... clauseN]
1004 Operand 0: OMP_FOR_BODY: Loop body.
1005 Operand 1: OMP_FOR_CLAUSES: List of clauses.
1006 Operand 2: OMP_FOR_INIT: Initialization code of the form
1008 Operand 3: OMP_FOR_COND: Loop conditional expression of the form
1009 VAR { <, >, <=, >= } N2.
1010 Operand 4: OMP_FOR_INCR: Loop index increment of the form
1011 VAR { +=, -= } INCR.
1012 Operand 5: OMP_FOR_PRE_BODY: Filled by the gimplifier with things
1013 from INIT, COND, and INCR that are technically part of the
1014 OMP_FOR structured block, but are evaluated before the loop
1017 VAR must be an integer or pointer variable, which is implicitly thread
1018 private. N1, N2 and INCR are required to be loop invariant integer
1019 expressions that are evaluated without any synchronization.
1020 The evaluation order, frequency of evaluation and side-effects are
1021 unspecified by the standard. */
1022 DEFTREECODE (OMP_FOR, "omp_for", tcc_statement, 6)
1024 /* OpenMP - #pragma omp sections [clause1 ... clauseN]
1025 Operand 0: OMP_SECTIONS_BODY: Sections body.
1026 Operand 1: OMP_SECTIONS_CLAUSES: List of clauses. */
1027 DEFTREECODE (OMP_SECTIONS, "omp_sections", tcc_statement, 2)
1029 /* OpenMP - #pragma omp single
1030 Operand 0: OMP_SINGLE_BODY: Single section body.
1031 Operand 1: OMP_SINGLE_CLAUSES: List of clauses. */
1032 DEFTREECODE (OMP_SINGLE, "omp_single", tcc_statement, 2)
1034 /* OpenMP - #pragma omp section
1035 Operand 0: OMP_SECTION_BODY: Section body. */
1036 DEFTREECODE (OMP_SECTION, "omp_section", tcc_statement, 1)
1038 /* OpenMP - #pragma omp master
1039 Operand 0: OMP_MASTER_BODY: Master section body. */
1040 DEFTREECODE (OMP_MASTER, "omp_master", tcc_statement, 1)
1042 /* OpenMP - #pragma omp ordered
1043 Operand 0: OMP_ORDERED_BODY: Master section body. */
1044 DEFTREECODE (OMP_ORDERED, "omp_ordered", tcc_statement, 1)
1046 /* OpenMP - #pragma omp critical [name]
1047 Operand 0: OMP_CRITICAL_BODY: Critical section body.
1048 Operand 1: OMP_CRITICAL_NAME: Identifier for critical section. */
1049 DEFTREECODE (OMP_CRITICAL, "omp_critical", tcc_statement, 2)
1051 /* OpenMP - #pragma omp atomic
1052 Operand 0: The address at which the atomic operation is to be performed.
1053 This address should be stabilized with save_expr.
1054 Operand 1: The expression to evaluate. When the old value of the object
1055 at the address is used in the expression, it should appear as if
1056 build_fold_indirect_ref of the address. */
1057 DEFTREECODE (OMP_ATOMIC, "omp_atomic", tcc_statement, 2)
1059 /* OpenMP - #pragma omp atomic read
1060 Operand 0: The address at which the atomic operation is to be performed.
1061 This address should be stabilized with save_expr. */
1062 DEFTREECODE (OMP_ATOMIC_READ, "omp_atomic_read", tcc_statement, 1)
1064 /* OpenMP - #pragma omp atomic capture
1065 Operand 0: The address at which the atomic operation is to be performed.
1066 This address should be stabilized with save_expr.
1067 Operand 1: The expression to evaluate. When the old value of the object
1068 at the address is used in the expression, it should appear as if
1069 build_fold_indirect_ref of the address.
1070 OMP_ATOMIC_CAPTURE_OLD returns the old memory content,
1071 OMP_ATOMIC_CAPTURE_NEW the new value. */
1072 DEFTREECODE (OMP_ATOMIC_CAPTURE_OLD, "omp_atomic_capture_old", tcc_statement, 2)
1073 DEFTREECODE (OMP_ATOMIC_CAPTURE_NEW, "omp_atomic_capture_new", tcc_statement, 2)
1075 /* OpenMP clauses. */
1076 DEFTREECODE (OMP_CLAUSE, "omp_clause", tcc_exceptional, 0)
1078 /* Reduction operations.
1079 Operations that take a vector of elements and "reduce" it to a scalar
1080 result (e.g. summing the elements of the vector, finding the minimum over
1081 the vector elements, etc).
1082 Operand 0 is a vector; the first element in the vector has the result.
1083 Operand 1 is a vector. */
1084 DEFTREECODE (REDUC_MAX_EXPR, "reduc_max_expr", tcc_unary, 1)
1085 DEFTREECODE (REDUC_MIN_EXPR, "reduc_min_expr", tcc_unary, 1)
1086 DEFTREECODE (REDUC_PLUS_EXPR, "reduc_plus_expr", tcc_unary, 1)
1088 /* Widening dot-product.
1089 The first two arguments are of type t1.
1090 The third argument and the result are of type t2, such that t2 is at least
1091 twice the size of t1. DOT_PROD_EXPR(arg1,arg2,arg3) is equivalent to:
1092 tmp = WIDEN_MULT_EXPR(arg1, arg2);
1093 arg3 = PLUS_EXPR (tmp, arg3);
1095 tmp = WIDEN_MULT_EXPR(arg1, arg2);
1096 arg3 = WIDEN_SUM_EXPR (tmp, arg3); */
1097 DEFTREECODE (DOT_PROD_EXPR, "dot_prod_expr", tcc_expression, 3)
1099 /* Widening summation.
1100 The first argument is of type t1.
1101 The second argument is of type t2, such that t2 is at least twice
1102 the size of t1. The type of the entire expression is also t2.
1103 WIDEN_SUM_EXPR is equivalent to first widening (promoting)
1104 the first argument from type t1 to type t2, and then summing it
1105 with the second argument. */
1106 DEFTREECODE (WIDEN_SUM_EXPR, "widen_sum_expr", tcc_binary, 2)
1108 /* Widening multiplication.
1109 The two arguments are of type t1.
1110 The result is of type t2, such that t2 is at least twice
1111 the size of t1. WIDEN_MULT_EXPR is equivalent to first widening (promoting)
1112 the arguments from type t1 to type t2, and then multiplying them. */
1113 DEFTREECODE (WIDEN_MULT_EXPR, "widen_mult_expr", tcc_binary, 2)
1115 /* Widening multiply-accumulate.
1116 The first two arguments are of type t1.
1117 The third argument and the result are of type t2, such as t2 is at least
1118 twice the size of t1. t1 and t2 must be integral or fixed-point types.
1119 The expression is equivalent to a WIDEN_MULT_EXPR operation
1120 of the first two operands followed by an add or subtract of the third
1122 DEFTREECODE (WIDEN_MULT_PLUS_EXPR, "widen_mult_plus_expr", tcc_expression, 3)
1123 /* This is like the above, except in the final expression the multiply result
1124 is subtracted from t3. */
1125 DEFTREECODE (WIDEN_MULT_MINUS_EXPR, "widen_mult_minus_expr", tcc_expression, 3)
1127 /* Fused multiply-add.
1128 All operands and the result are of the same type. No intermediate
1129 rounding is performed after multiplying operand one with operand two
1130 before adding operand three. */
1131 DEFTREECODE (FMA_EXPR, "fma_expr", tcc_expression, 3)
1133 /* Whole vector left/right shift in bits.
1134 Operand 0 is a vector to be shifted.
1135 Operand 1 is an integer shift amount in bits. */
1136 DEFTREECODE (VEC_LSHIFT_EXPR, "vec_lshift_expr", tcc_binary, 2)
1137 DEFTREECODE (VEC_RSHIFT_EXPR, "vec_rshift_expr", tcc_binary, 2)
1139 /* Widening vector multiplication.
1140 The two operands are vectors with N elements of size S. Multiplying the
1141 elements of the two vectors will result in N products of size 2*S.
1142 VEC_WIDEN_MULT_HI_EXPR computes the N/2 high products.
1143 VEC_WIDEN_MULT_LO_EXPR computes the N/2 low products. */
1144 DEFTREECODE (VEC_WIDEN_MULT_HI_EXPR, "widen_mult_hi_expr", tcc_binary, 2)
1145 DEFTREECODE (VEC_WIDEN_MULT_LO_EXPR, "widen_mult_lo_expr", tcc_binary, 2)
1147 /* Unpack (extract and promote/widen) the high/low elements of the input
1148 vector into the output vector. The input vector has twice as many
1149 elements as the output vector, that are half the size of the elements
1150 of the output vector. This is used to support type promotion. */
1151 DEFTREECODE (VEC_UNPACK_HI_EXPR, "vec_unpack_hi_expr", tcc_unary, 1)
1152 DEFTREECODE (VEC_UNPACK_LO_EXPR, "vec_unpack_lo_expr", tcc_unary, 1)
1154 /* Unpack (extract) the high/low elements of the input vector, convert
1155 fixed point values to floating point and widen elements into the
1156 output vector. The input vector has twice as many elements as the output
1157 vector, that are half the size of the elements of the output vector. */
1158 DEFTREECODE (VEC_UNPACK_FLOAT_HI_EXPR, "vec_unpack_float_hi_expr", tcc_unary, 1)
1159 DEFTREECODE (VEC_UNPACK_FLOAT_LO_EXPR, "vec_unpack_float_lo_expr", tcc_unary, 1)
1161 /* Pack (demote/narrow and merge) the elements of the two input vectors
1162 into the output vector using truncation/saturation.
1163 The elements of the input vectors are twice the size of the elements of the
1164 output vector. This is used to support type demotion. */
1165 DEFTREECODE (VEC_PACK_TRUNC_EXPR, "vec_pack_trunc_expr", tcc_binary, 2)
1166 DEFTREECODE (VEC_PACK_SAT_EXPR, "vec_pack_sat_expr", tcc_binary, 2)
1168 /* Convert floating point values of the two input vectors to integer
1169 and pack (narrow and merge) the elements into the output vector. The
1170 elements of the input vector are twice the size of the elements of
1171 the output vector. */
1172 DEFTREECODE (VEC_PACK_FIX_TRUNC_EXPR, "vec_pack_fix_trunc_expr", tcc_binary, 2)
1174 /* Extract even/odd fields from vectors. */
1175 DEFTREECODE (VEC_EXTRACT_EVEN_EXPR, "vec_extracteven_expr", tcc_binary, 2)
1176 DEFTREECODE (VEC_EXTRACT_ODD_EXPR, "vec_extractodd_expr", tcc_binary, 2)
1178 /* Merge input vectors interleaving their fields. */
1179 DEFTREECODE (VEC_INTERLEAVE_HIGH_EXPR, "vec_interleavehigh_expr", tcc_binary, 2)
1180 DEFTREECODE (VEC_INTERLEAVE_LOW_EXPR, "vec_interleavelow_expr", tcc_binary, 2)
1182 /* PREDICT_EXPR. Specify hint for branch prediction. The
1183 PREDICT_EXPR_PREDICTOR specify predictor and PREDICT_EXPR_OUTCOME the
1184 outcome (0 for not taken and 1 for taken). Once the profile is guessed
1185 all conditional branches leading to execution paths executing the
1186 PREDICT_EXPR will get predicted by the specified predictor. */
1187 DEFTREECODE (PREDICT_EXPR, "predict_expr", tcc_expression, 1)
1189 /* OPTIMIZATION_NODE. Node to store the optimization options. */
1190 DEFTREECODE (OPTIMIZATION_NODE, "optimization_node", tcc_exceptional, 0)
1192 /* TARGET_OPTION_NODE. Node to store the target specific options. */
1193 DEFTREECODE (TARGET_OPTION_NODE, "target_option_node", tcc_exceptional, 0)