1/* This file contains the definitions and documentation for the
2   tree codes used in GCC.
3   Copyright (C) 1987-2021 Free Software Foundation, Inc.
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it under
8the terms of the GNU General Public License as published by the Free
9Software Foundation; either version 3, or (at your option) any later
10version.
11
12GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13WARRANTY; without even the implied warranty of MERCHANTABILITY or
14FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING3.  If not see
19<http://www.gnu.org/licenses/>.  */
20
21
22/* For tcc_references, tcc_expression, tcc_comparison, tcc_unary,
23   tcc_binary, and tcc_statement nodes, which use struct tree_exp, the
24   4th element is the number of argument slots to allocate.  This
25   determines the size of the tree node object.  Other nodes use
26   different structures, and the size is determined by the tree_union
27   member structure; the 4th element should be zero.  Languages that
28   define language-specific tcc_exceptional or tcc_constant codes must
29   define the tree_size langhook to say how big they are.
30
31   These tree codes have been sorted so that the macros in tree.h that
32   check for various tree codes are optimized into range checks.  This
33   gives a measurable performance improvement.  When adding a new
34   code, consider its placement in relation to the other codes.  */
35
36/* Any erroneous construct is parsed into a node of this type.
37   This type of node is accepted without complaint in all contexts
38   by later parsing activities, to avoid multiple error messages
39   for one error.
40   No fields in these nodes are used except the TREE_CODE.  */
41DEFTREECODE (ERROR_MARK, "error_mark", tcc_exceptional, 0)
42
43/* Used to represent a name (such as, in the DECL_NAME of a decl node).
44   Internally it looks like a STRING_CST node.
45   There is only one IDENTIFIER_NODE ever made for any particular name.
46   Use `get_identifier' to get it (or create it, the first time).  */
47DEFTREECODE (IDENTIFIER_NODE, "identifier_node", tcc_exceptional, 0)
48
49/* Has the TREE_VALUE and TREE_PURPOSE fields.  */
50/* These nodes are made into lists by chaining through the
51   TREE_CHAIN field.  The elements of the list live in the
52   TREE_VALUE fields, while TREE_PURPOSE fields are occasionally
53   used as well to get the effect of Lisp association lists.  */
54DEFTREECODE (TREE_LIST, "tree_list", tcc_exceptional, 0)
55
56/* These nodes contain an array of tree nodes.  */
57DEFTREECODE (TREE_VEC, "tree_vec", tcc_exceptional, 0)
58
59/* A symbol binding block.  These are arranged in a tree,
60   where the BLOCK_SUBBLOCKS field contains a chain of subblocks
61   chained through the BLOCK_CHAIN field.
62   BLOCK_SUPERCONTEXT points to the parent block.
63     For a block which represents the outermost scope of a function, it
64     points to the FUNCTION_DECL node.
65   BLOCK_VARS points to a chain of decl nodes.
66   BLOCK_CHAIN points to the next BLOCK at the same level.
67   BLOCK_ABSTRACT_ORIGIN points to the original (abstract) tree node which
68   this block is an instance of, or else is NULL to indicate that this
69   block is not an instance of anything else.  When non-NULL, the value
70   could either point to another BLOCK node or it could point to a
71   FUNCTION_DECL node (e.g. in the case of a block representing the
72   outermost scope of a particular inlining of a function).
73   TREE_ASM_WRITTEN is nonzero if the block was actually referenced
74   in the generated assembly.  */
75DEFTREECODE (BLOCK, "block", tcc_exceptional, 0)
76
77/* Each data type is represented by a tree node whose code is one of
78   the following:  */
79/* Each node that represents a data type has a component TYPE_SIZE
80   that evaluates either to a tree that is a (potentially non-constant)
81   expression representing the type size in bits, or to a null pointer
82   when the size of the type is unknown (for example, for incomplete
83   types such as arrays of unspecified bound).
84   The TYPE_MODE contains the machine mode for values of this type.
85   The TYPE_POINTER_TO field contains a type for a pointer to this type,
86     or zero if no such has been created yet.
87   The TYPE_NEXT_VARIANT field is used to chain together types
88     that are variants made by type modifiers such as "const" and "volatile".
89   The TYPE_MAIN_VARIANT field, in any member of such a chain,
90     points to the start of the chain.
91   The TYPE_NAME field contains info on the name used in the program
92     for this type (for GDB symbol table output).  It is either a
93     TYPE_DECL node, for types that are typedefs, or an IDENTIFIER_NODE
94     in the case of structs, unions or enums that are known with a tag,
95     or zero for types that have no special name.
96   The TYPE_CONTEXT for any sort of type which could have a name or
97    which could have named members (e.g. tagged types in C/C++) will
98    point to the node which represents the scope of the given type, or
99    will be NULL_TREE if the type has "file scope".  For most types, this
100    will point to a BLOCK node or a FUNCTION_DECL node, but it could also
101    point to a FUNCTION_TYPE node (for types whose scope is limited to the
102    formal parameter list of some function type specification) or it
103    could point to a RECORD_TYPE, UNION_TYPE or QUAL_UNION_TYPE node
104    (for C++ "member" types).
105    For non-tagged-types, TYPE_CONTEXT need not be set to anything in
106    particular, since any type which is of some type category  (e.g.
107    an array type or a function type) which cannot either have a name
108    itself or have named members doesn't really have a "scope" per se.
109  The TYPE_STUB_DECL field is used as a forward-references to names for
110    ENUMERAL_TYPE, RECORD_TYPE, UNION_TYPE, and QUAL_UNION_TYPE nodes;
111    see below.  */
112
113/* The ordering of the following codes is optimized for the checking
114   macros in tree.h.  Changing the order will degrade the speed of the
115   compiler.  OFFSET_TYPE, ENUMERAL_TYPE, BOOLEAN_TYPE, INTEGER_TYPE,
116   REAL_TYPE, POINTER_TYPE.  */
117
118/* An offset is a pointer relative to an object.
119   The TREE_TYPE field is the type of the object at the offset.
120   The TYPE_OFFSET_BASETYPE points to the node for the type of object
121   that the offset is relative to.  */
122DEFTREECODE (OFFSET_TYPE, "offset_type", tcc_type, 0)
123
124/* C enums.  The type node looks just like an INTEGER_TYPE node.
125   The symbols for the values of the enum type are defined by
126   CONST_DECL nodes, but the type does not point to them;
127   however, the TYPE_VALUES is a list in which each element's TREE_PURPOSE
128   is a name and the TREE_VALUE is the value (an INTEGER_CST node).  */
129/* A forward reference `enum foo' when no enum named foo is defined yet
130   has zero (a null pointer) in its TYPE_SIZE.  The tag name is in
131   the TYPE_NAME field.  If the type is later defined, the normal
132   fields are filled in.
133   RECORD_TYPE, UNION_TYPE, and QUAL_UNION_TYPE forward refs are
134   treated similarly.  */
135DEFTREECODE (ENUMERAL_TYPE, "enumeral_type", tcc_type, 0)
136
137/* Boolean type (true or false are the only values).  Looks like an
138   INTEGRAL_TYPE.  */
139DEFTREECODE (BOOLEAN_TYPE, "boolean_type", tcc_type, 0)
140
141/* Integer types in all languages, including char in C.
142   Also used for sub-ranges of other discrete types.
143   Has components TYPE_MIN_VALUE, TYPE_MAX_VALUE (expressions, inclusive)
144   and TYPE_PRECISION (number of bits used by this type).  */
145DEFTREECODE (INTEGER_TYPE, "integer_type", tcc_type, 0)
146
147/* C's float and double.  Different floating types are distinguished
148   by machine mode and by the TYPE_SIZE and the TYPE_PRECISION.  */
149DEFTREECODE (REAL_TYPE, "real_type", tcc_type, 0)
150
151/* The ordering of the following codes is optimized for the checking
152   macros in tree.h.  Changing the order will degrade the speed of the
153   compiler.  POINTER_TYPE, REFERENCE_TYPE.  Note that this range
154   overlaps the previous range of ordered types.  */
155
156/* All pointer-to-x types have code POINTER_TYPE.
157   The TREE_TYPE points to the node for the type pointed to.  */
158DEFTREECODE (POINTER_TYPE, "pointer_type", tcc_type, 0)
159
160/* A reference is like a pointer except that it is coerced
161   automatically to the value it points to.  Used in C++.  */
162DEFTREECODE (REFERENCE_TYPE, "reference_type", tcc_type, 0)
163
164/* The C++ decltype(nullptr) type.  */
165DEFTREECODE (NULLPTR_TYPE, "nullptr_type", tcc_type, 0)
166
167/* _Fract and _Accum types in Embedded-C.  Different fixed-point types
168   are distinguished by machine mode and by the TYPE_SIZE and the
169   TYPE_PRECISION.  */
170DEFTREECODE (FIXED_POINT_TYPE, "fixed_point_type", tcc_type, 0)
171
172/* The ordering of the following codes is optimized for the checking
173   macros in tree.h.  Changing the order will degrade the speed of the
174   compiler.  COMPLEX_TYPE, VECTOR_TYPE, ARRAY_TYPE.  */
175
176/* Complex number types.  The TREE_TYPE field is the data type
177   of the real and imaginary parts.  It must be of scalar
178   arithmetic type, not including pointer type.  */
179DEFTREECODE (COMPLEX_TYPE, "complex_type", tcc_type, 0)
180
181/* Vector types.  The TREE_TYPE field is the data type of the vector
182   elements.  The TYPE_PRECISION field is the number of subparts of
183   the vector.  */
184DEFTREECODE (VECTOR_TYPE, "vector_type", tcc_type, 0)
185
186/* The ordering of the following codes is optimized for the checking
187   macros in tree.h.  Changing the order will degrade the speed of the
188   compiler.  ARRAY_TYPE, RECORD_TYPE, UNION_TYPE, QUAL_UNION_TYPE.
189   Note that this range overlaps the previous range.  */
190
191/* Types of arrays.  Special fields:
192   TREE_TYPE		  Type of an array element.
193   TYPE_DOMAIN		  Type to index by.
194			    Its range of values specifies the array length.
195 The field TYPE_POINTER_TO (TREE_TYPE (array_type)) is always nonzero
196 and holds the type to coerce a value of that array type to in C.
197 TYPE_STRING_FLAG indicates a string (in contrast to an array of chars)
198 in languages (such as Chill) that make a distinction.  */
199/* Array types in C */
200DEFTREECODE (ARRAY_TYPE, "array_type", tcc_type, 0)
201
202/* Struct in C.  */
203/* Special fields:
204   TYPE_FIELDS  chain of FIELD_DECLs for the fields of the struct,
205     VAR_DECLs, TYPE_DECLs and CONST_DECLs for record-scope variables,
206     types and enumerators and FUNCTION_DECLs for methods associated
207     with the type.  */
208/* See the comment above, before ENUMERAL_TYPE, for how
209   forward references to struct tags are handled in C.  */
210DEFTREECODE (RECORD_TYPE, "record_type", tcc_type, 0)
211
212/* Union in C.  Like a struct, except that the offsets of the fields
213   will all be zero.  */
214/* See the comment above, before ENUMERAL_TYPE, for how
215   forward references to union tags are handled in C.  */
216DEFTREECODE (UNION_TYPE, "union_type", tcc_type, 0)	/* C union type */
217
218/* Similar to UNION_TYPE, except that the expressions in DECL_QUALIFIER
219   in each FIELD_DECL determine what the union contains.  The first
220   field whose DECL_QUALIFIER expression is true is deemed to occupy
221   the union.  */
222DEFTREECODE (QUAL_UNION_TYPE, "qual_union_type", tcc_type, 0)
223
224/* The ordering of the following codes is optimized for the checking
225   macros in tree.h.  Changing the order will degrade the speed of the
226   compiler.  VOID_TYPE, FUNCTION_TYPE, METHOD_TYPE.  */
227
228/* The void type in C */
229DEFTREECODE (VOID_TYPE, "void_type", tcc_type, 0)
230
231/* Type of functions.  Special fields:
232   TREE_TYPE		    type of value returned.
233   TYPE_ARG_TYPES      list of types of arguments expected.
234	this list is made of TREE_LIST nodes.
235	In this list TREE_PURPOSE can be used to indicate the default
236	value of parameter (used by C++ frontend).
237   Types of "Procedures" in languages where they are different from functions
238   have code FUNCTION_TYPE also, but then TREE_TYPE is zero or void type.  */
239DEFTREECODE (FUNCTION_TYPE, "function_type", tcc_type, 0)
240
241/* METHOD_TYPE is the type of a function which takes an extra first
242   argument for "self", which is not present in the declared argument list.
243   The TREE_TYPE is the return type of the method.  The TYPE_METHOD_BASETYPE
244   is the type of "self".  TYPE_ARG_TYPES is the real argument list, which
245   includes the hidden argument for "self".  */
246DEFTREECODE (METHOD_TYPE, "method_type", tcc_type, 0)
247
248/* This is a language-specific kind of type.
249   Its meaning is defined by the language front end.
250   layout_type does not know how to lay this out,
251   so the front-end must do so manually.  */
252DEFTREECODE (LANG_TYPE, "lang_type", tcc_type, 0)
253
254/* This is for types that will use MODE_OPAQUE in the back end.  They are meant
255   to be able to go in a register of some sort but are explicitly not to be
256   converted or operated on like INTEGER_TYPE.  They will have size and
257   alignment information only.  */
258DEFTREECODE (OPAQUE_TYPE, "opaque_type", tcc_type, 0)
259
260/* Expressions */
261
262/* First, the constants.  */
263
264DEFTREECODE (VOID_CST, "void_cst", tcc_constant, 0)
265
266/* Contents are in an array of HOST_WIDE_INTs.
267
268   We often access these constants both in their native precision and
269   in wider precisions (with the constant being implicitly extended
270   according to TYPE_SIGN).  In each case, the useful part of the array
271   may be as wide as the precision requires but may be shorter when all
272   of the upper bits are sign bits.  The length of the array when accessed
273   in the constant's native precision is given by TREE_INT_CST_NUNITS.
274   The length of the array when accessed in wider precisions is given
275   by TREE_INT_CST_EXT_NUNITS.  Each element can be obtained using
276   TREE_INT_CST_ELT.
277
278   INTEGER_CST nodes can be shared, and therefore should be considered
279   read only.  They should be copied before setting a flag such as
280   TREE_OVERFLOW.  If an INTEGER_CST has TREE_OVERFLOW already set,
281   it is known to be unique.  INTEGER_CST nodes are created for the
282   integral types, for pointer types and for vector and float types in
283   some circumstances.  */
284DEFTREECODE (INTEGER_CST, "integer_cst", tcc_constant, 0)
285
286/* Contents are given by POLY_INT_CST_COEFF.  */
287DEFTREECODE (POLY_INT_CST, "poly_int_cst", tcc_constant, 0)
288
289/* Contents are in TREE_REAL_CST field.  */
290DEFTREECODE (REAL_CST, "real_cst", tcc_constant, 0)
291
292/* Contents are in TREE_FIXED_CST field.  */
293DEFTREECODE (FIXED_CST, "fixed_cst", tcc_constant, 0)
294
295/* Contents are in TREE_REALPART and TREE_IMAGPART fields,
296   whose contents are other constant nodes.  */
297DEFTREECODE (COMPLEX_CST, "complex_cst", tcc_constant, 0)
298
299/* See generic.texi for details.  */
300DEFTREECODE (VECTOR_CST, "vector_cst", tcc_constant, 0)
301
302/* Contents are TREE_STRING_LENGTH and the actual contents of the string.  */
303DEFTREECODE (STRING_CST, "string_cst", tcc_constant, 0)
304
305/* Declarations.  All references to names are represented as ..._DECL
306   nodes.  The decls in one binding context are chained through the
307   TREE_CHAIN field.  Each DECL has a DECL_NAME field which contains
308   an IDENTIFIER_NODE.  (Some decls, most often labels, may have zero
309   as the DECL_NAME).  DECL_CONTEXT points to the node representing
310   the context in which this declaration has its scope.  For
311   FIELD_DECLs, this is the RECORD_TYPE, UNION_TYPE, or
312   QUAL_UNION_TYPE node that the field is a member of.  For VAR_DECL,
313   PARM_DECL, FUNCTION_DECL, LABEL_DECL, and CONST_DECL nodes, this
314   points to either the FUNCTION_DECL for the containing function, the
315   RECORD_TYPE or UNION_TYPE for the containing type, or NULL_TREE or
316   a TRANSLATION_UNIT_DECL if the given decl has "file scope".
317   DECL_ABSTRACT_ORIGIN, if non-NULL, points to the original (abstract)
318    ..._DECL node of which this decl is an (inlined or template expanded)
319    instance.
320   The TREE_TYPE field holds the data type of the object, when relevant.
321    LABEL_DECLs have no data type.  For TYPE_DECL, the TREE_TYPE field
322    contents are the type whose name is being declared.
323   The DECL_ALIGN, DECL_SIZE,
324    and DECL_MODE fields exist in decl nodes just as in type nodes.
325    They are unused in LABEL_DECL, TYPE_DECL and CONST_DECL nodes.
326
327   DECL_FIELD_BIT_OFFSET holds an integer number of bits offset for
328   the location.  DECL_VOFFSET holds an expression for a variable
329   offset; it is to be multiplied by DECL_VOFFSET_UNIT (an integer).
330   These fields are relevant only in FIELD_DECLs and PARM_DECLs.
331
332   DECL_INITIAL holds the value to initialize a variable to,
333   or the value of a constant.  For a function, it holds the body
334   (a node of type BLOCK representing the function's binding contour
335   and whose body contains the function's statements.)  For a LABEL_DECL
336   in C, it is a flag, nonzero if the label's definition has been seen.
337
338   PARM_DECLs use a special field:
339   DECL_ARG_TYPE is the type in which the argument is actually
340    passed, which may be different from its type within the function.
341
342   FUNCTION_DECLs use four special fields:
343   DECL_ARGUMENTS holds a chain of PARM_DECL nodes for the arguments.
344   DECL_RESULT holds a RESULT_DECL node for the value of a function.
345    The DECL_RTL field is 0 for a function that returns no value.
346    (C functions returning void have zero here.)
347    The TREE_TYPE field is the type in which the result is actually
348    returned.  This is usually the same as the return type of the
349    FUNCTION_DECL, but it may be a wider integer type because of
350    promotion.
351   DECL_FUNCTION_CODE is a code number that is nonzero for
352    built-in functions.  Its value is an enum built_in_function
353    that says which built-in function it is.
354
355   DECL_SOURCE_FILE holds a filename string and DECL_SOURCE_LINE
356   holds a line number.  In some cases these can be the location of
357   a reference, if no definition has been seen.
358
359   DECL_ABSTRACT is nonzero if the decl represents an abstract instance
360   of a decl (i.e. one which is nested within an abstract instance of a
361   inline function.  */
362
363DEFTREECODE (FUNCTION_DECL, "function_decl", tcc_declaration, 0)
364DEFTREECODE (LABEL_DECL, "label_decl", tcc_declaration, 0)
365/* The ordering of the following codes is optimized for the checking
366   macros in tree.h.  Changing the order will degrade the speed of the
367   compiler.  FIELD_DECL, VAR_DECL, CONST_DECL, PARM_DECL,
368   TYPE_DECL.  */
369DEFTREECODE (FIELD_DECL, "field_decl", tcc_declaration, 0)
370DEFTREECODE (VAR_DECL, "var_decl", tcc_declaration, 0)
371DEFTREECODE (CONST_DECL, "const_decl", tcc_declaration, 0)
372DEFTREECODE (PARM_DECL, "parm_decl", tcc_declaration, 0)
373DEFTREECODE (TYPE_DECL, "type_decl", tcc_declaration, 0)
374DEFTREECODE (RESULT_DECL, "result_decl", tcc_declaration, 0)
375
376/* A "declaration" of a debug temporary.  It should only appear in
377   DEBUG stmts.  */
378DEFTREECODE (DEBUG_EXPR_DECL, "debug_expr_decl", tcc_declaration, 0)
379
380/* A stmt that marks the beginning of a source statement.  */
381DEFTREECODE (DEBUG_BEGIN_STMT, "debug_begin_stmt", tcc_statement, 0)
382
383/* A namespace declaration.  Namespaces appear in DECL_CONTEXT of other
384   _DECLs, providing a hierarchy of names.  */
385DEFTREECODE (NAMESPACE_DECL, "namespace_decl", tcc_declaration, 0)
386
387/* A declaration import.
388   The C++ FE uses this to represent a using-directive; eg:
389   "using namespace foo".
390   But it could be used to represent any declaration import construct.
391   Whenever a declaration import appears in a lexical block, the BLOCK node
392   representing that lexical block in GIMPLE will contain an IMPORTED_DECL
393   node, linked via BLOCK_VARS accessor of the said BLOCK.
394   For a given NODE which code is IMPORTED_DECL,
395   IMPORTED_DECL_ASSOCIATED_DECL (NODE) accesses the imported declaration.  */
396DEFTREECODE (IMPORTED_DECL, "imported_decl", tcc_declaration, 0)
397
398/* A namelist declaration.
399   The Fortran FE uses this to represent a namelist statement, e.g.:
400   NAMELIST /namelist-group-name/ namelist-group-object-list.
401   Whenever a declaration import appears in a lexical block, the BLOCK node
402   representing that lexical block in GIMPLE will contain an NAMELIST_DECL
403   node, linked via BLOCK_VARS accessor of the said BLOCK.
404   For a given NODE which code is NAMELIST_DECL,
405   NAMELIST_DECL_ASSOCIATED_DECL (NODE) accesses the imported declaration.  */
406DEFTREECODE (NAMELIST_DECL, "namelist_decl", tcc_declaration, 0)
407
408/* A translation unit.  This is not technically a declaration, since it
409   can't be looked up, but it's close enough.  */
410DEFTREECODE (TRANSLATION_UNIT_DECL, "translation_unit_decl",\
411	     tcc_declaration, 0)
412
413/* References to storage.  */
414
415/* The ordering of the following codes is optimized for the classification
416   in handled_component_p.  Keep them in a consecutive group.  */
417
418/* Value is structure or union component.
419   Operand 0 is the structure or union (an expression).
420   Operand 1 is the field (a node of type FIELD_DECL).
421   Operand 2, if present, is the value of DECL_FIELD_OFFSET, measured
422   in units of DECL_OFFSET_ALIGN / BITS_PER_UNIT.  */
423DEFTREECODE (COMPONENT_REF, "component_ref", tcc_reference, 3)
424
425/* Reference to a group of bits within an object.  Similar to COMPONENT_REF
426   except the position is given explicitly rather than via a FIELD_DECL.
427   Operand 0 is the structure or union expression;
428   operand 1 is a tree giving the constant number of bits being referenced;
429   operand 2 is a tree giving the constant position of the first referenced bit.
430   The result type width has to match the number of bits referenced.
431   If the result type is integral, its signedness specifies how it is extended
432   to its mode width.  */
433DEFTREECODE (BIT_FIELD_REF, "bit_field_ref", tcc_reference, 3)
434
435/* Array indexing.
436   Operand 0 is the array; operand 1 is a (single) array index.
437   Operand 2, if present, is a copy of TYPE_MIN_VALUE of the index.
438   Operand 3, if present, is the element size, measured in units of
439   the alignment of the element type.  */
440DEFTREECODE (ARRAY_REF, "array_ref", tcc_reference, 4)
441
442/* Likewise, except that the result is a range ("slice") of the array.  The
443   starting index of the resulting array is taken from operand 1 and the size
444   of the range is taken from the type of the expression.  */
445DEFTREECODE (ARRAY_RANGE_REF, "array_range_ref", tcc_reference, 4)
446
447/* Used only on an operand of complex type, these return
448   a value of the corresponding component type.  */
449DEFTREECODE (REALPART_EXPR, "realpart_expr", tcc_reference, 1)
450DEFTREECODE (IMAGPART_EXPR, "imagpart_expr", tcc_reference, 1)
451
452/* Represents viewing something of one type as being of a second type.
453   This corresponds to an "Unchecked Conversion" in Ada and roughly to
454   the idiom *(type2 *)&X in C.  The only operand is the value to be
455   viewed as being of another type.  It is undefined if the type of the
456   input and of the expression have different sizes.
457
458   This code may also be used within the LHS of a MODIFY_EXPR, in which
459   case no actual data motion may occur.  TREE_ADDRESSABLE will be set in
460   this case and GCC must abort if it could not do the operation without
461   generating insns.  */
462DEFTREECODE (VIEW_CONVERT_EXPR, "view_convert_expr", tcc_reference, 1)
463
464/* C unary `*'.  One operand, an expression for a pointer.  */
465DEFTREECODE (INDIRECT_REF, "indirect_ref", tcc_reference, 1)
466
467/* Used to represent lookup in a virtual method table which is dependent on
468   the runtime type of an object.  Operands are:
469   OBJ_TYPE_REF_EXPR: An expression that evaluates the value to use.
470   OBJ_TYPE_REF_OBJECT: Is the object on whose behalf the lookup is
471   being performed.  Through this the optimizers may be able to statically
472   determine the dynamic type of the object.
473   OBJ_TYPE_REF_TOKEN: An integer index to the virtual method table.  */
474DEFTREECODE (OBJ_TYPE_REF, "obj_type_ref", tcc_expression, 3)
475
476/* Used to represent the brace-enclosed initializers for a structure or an
477   array.  It contains a sequence of component values made out of a VEC of
478   constructor_elt.
479
480   For RECORD_TYPE, UNION_TYPE, or QUAL_UNION_TYPE:
481   The field INDEX of each constructor_elt is a FIELD_DECL.
482
483   For ARRAY_TYPE:
484   The field INDEX of each constructor_elt is the corresponding index.
485   If the index is a RANGE_EXPR, it is a short-hand for many nodes,
486   one for each index in the range.  (If the corresponding field VALUE
487   has side-effects, they are evaluated once for each element.  Wrap the
488   value in a SAVE_EXPR if you want to evaluate side effects only once.)
489
490   Components that aren't present are cleared as per the C semantics,
491   unless the CONSTRUCTOR_NO_CLEARING flag is set, in which case their
492   value becomes undefined.  */
493DEFTREECODE (CONSTRUCTOR, "constructor", tcc_exceptional, 0)
494
495/* The expression types are mostly straightforward, with the fourth argument
496   of DEFTREECODE saying how many operands there are.
497   Unless otherwise specified, the operands are expressions and the
498   types of all the operands and the expression must all be the same.  */
499
500/* Contains two expressions to compute, one followed by the other.
501   the first value is ignored.  The second one's value is used.  The
502   type of the first expression need not agree with the other types.  */
503DEFTREECODE (COMPOUND_EXPR, "compound_expr", tcc_expression, 2)
504
505/* Assignment expression.  Operand 0 is the what to set; 1, the new value.  */
506DEFTREECODE (MODIFY_EXPR, "modify_expr", tcc_expression, 2)
507
508/* Initialization expression.  Operand 0 is the variable to initialize;
509   Operand 1 is the initializer.  This differs from MODIFY_EXPR in that any
510   reference to the referent of operand 0 within operand 1 is undefined.  */
511DEFTREECODE (INIT_EXPR, "init_expr", tcc_expression, 2)
512
513/* For TARGET_EXPR, operand 0 is the target of an initialization,
514   operand 1 is the initializer for the target, which may be void
515     if simply expanding it initializes the target.
516   operand 2 is the cleanup for this node, if any.
517   operand 3 is the saved initializer after this node has been
518   expanded once; this is so we can re-expand the tree later.  */
519DEFTREECODE (TARGET_EXPR, "target_expr", tcc_expression, 4)
520
521/* Conditional expression ( ... ? ... : ...  in C).
522   Operand 0 is the condition.
523   Operand 1 is the then-value.
524   Operand 2 is the else-value.
525   Operand 0 may be of any type.
526   Operand 1 must have the same type as the entire expression, unless
527   it unconditionally throws an exception, in which case it should
528   have VOID_TYPE.  The same constraints apply to operand 2.  The
529   condition in operand 0 must be of integral type.
530
531   In cfg gimple, if you do not have a selection expression, operands
532   1 and 2 are NULL.  The operands are then taken from the cfg edges. */
533DEFTREECODE (COND_EXPR, "cond_expr", tcc_expression, 3)
534
535/* Represents a vector in which every element is equal to operand 0.  */
536DEFTREECODE (VEC_DUPLICATE_EXPR, "vec_duplicate_expr", tcc_unary, 1)
537
538/* Vector series created from a start (base) value and a step.
539
540   A = VEC_SERIES_EXPR (B, C)
541
542   means
543
544   for (i = 0; i < N; i++)
545     A[i] = B + C * i;  */
546DEFTREECODE (VEC_SERIES_EXPR, "vec_series_expr", tcc_binary, 2)
547
548/* Vector conditional expression. It is like COND_EXPR, but with
549   vector operands.
550
551   A = VEC_COND_EXPR ( X < Y, B, C)
552
553   means
554
555   for (i=0; i<N; i++)
556     A[i] = X[i] < Y[i] ? B[i] : C[i];
557*/
558DEFTREECODE (VEC_COND_EXPR, "vec_cond_expr", tcc_expression, 3)
559
560/* Vector permutation expression.  A = VEC_PERM_EXPR<v0, v1, mask> means
561
562   N = length(mask)
563   foreach i in N:
564     M = mask[i] % (2*N)
565     A = M < N ? v0[M] : v1[M-N]
566
567   V0 and V1 are vectors of the same type.  MASK is an integer-typed
568   vector.  The number of MASK elements must be the same with the
569   number of elements in V0 and V1.  The size of the inner type
570   of the MASK and of the V0 and V1 must be the same.
571*/
572DEFTREECODE (VEC_PERM_EXPR, "vec_perm_expr", tcc_expression, 3)
573
574/* Declare local variables, including making RTL and allocating space.
575   BIND_EXPR_VARS is a chain of VAR_DECL nodes for the variables.
576   BIND_EXPR_BODY is the body, the expression to be computed using
577   the variables.  The value of operand 1 becomes that of the BIND_EXPR.
578   BIND_EXPR_BLOCK is the BLOCK that corresponds to these bindings
579   for debugging purposes.  If this BIND_EXPR is actually expanded,
580   that sets the TREE_USED flag in the BLOCK.
581
582   The BIND_EXPR is not responsible for informing parsers
583   about these variables.  If the body is coming from the input file,
584   then the code that creates the BIND_EXPR is also responsible for
585   informing the parser of the variables.
586
587   If the BIND_EXPR is ever expanded, its TREE_USED flag is set.
588   This tells the code for debugging symbol tables not to ignore the BIND_EXPR.
589   If the BIND_EXPR should be output for debugging but will not be expanded,
590   set the TREE_USED flag by hand.
591
592   In order for the BIND_EXPR to be known at all, the code that creates it
593   must also install it as a subblock in the tree of BLOCK
594   nodes for the function.  */
595DEFTREECODE (BIND_EXPR, "bind_expr", tcc_expression, 3)
596
597/* Function call.  CALL_EXPRs are represented by variably-sized expression
598   nodes.  There are at least three fixed operands.  Operand 0 is an
599   INTEGER_CST node containing the total operand count, the number of
600   arguments plus 3.  Operand 1 is the function or NULL, while operand 2 is
601   is static chain argument, or NULL.  The remaining operands are the
602   arguments to the call.  */
603DEFTREECODE (CALL_EXPR, "call_expr", tcc_vl_exp, 3)
604
605/* Specify a value to compute along with its corresponding cleanup.
606   Operand 0 is the cleanup expression.
607   The cleanup is executed by the first enclosing CLEANUP_POINT_EXPR,
608   which must exist.  This differs from TRY_CATCH_EXPR in that operand 1
609   is always evaluated when cleanups are run.  */
610DEFTREECODE (WITH_CLEANUP_EXPR, "with_cleanup_expr", tcc_expression, 1)
611
612/* Specify a cleanup point.
613   Operand 0 is an expression that may have cleanups.  If it does, those
614   cleanups are executed after the expression is expanded.
615
616   Note that if the expression is a reference to storage, it is forced out
617   of memory before the cleanups are run.  This is necessary to handle
618   cases where the cleanups modify the storage referenced; in the
619   expression 't.i', if 't' is a struct with an integer member 'i' and a
620   cleanup which modifies 'i', the value of the expression depends on
621   whether the cleanup is run before or after 't.i' is evaluated.  When
622   expand_expr is run on 't.i', it returns a MEM.  This is not good enough;
623   the value of 't.i' must be forced out of memory.
624
625   As a consequence, the operand of a CLEANUP_POINT_EXPR must not have
626   BLKmode, because it will not be forced out of memory.  */
627DEFTREECODE (CLEANUP_POINT_EXPR, "cleanup_point_expr", tcc_expression, 1)
628
629/* The following code is used in languages that have types where some
630   field in an object of the type contains a value that is used in the
631   computation of another field's offset or size and/or the size of the
632   type.  The positions and/or sizes of fields can vary from object to
633   object of the same type or even for one and the same object within
634   its scope.
635
636   Record types with discriminants in Ada are
637   examples of such types.  This mechanism is also used to create "fat
638   pointers" for unconstrained array types in Ada; the fat pointer is a
639   structure one of whose fields is a pointer to the actual array type
640   and the other field is a pointer to a template, which is a structure
641   containing the bounds of the array.  The bounds in the type pointed
642   to by the first field in the fat pointer refer to the values in the
643   template.
644
645   When you wish to construct such a type you need "self-references"
646   that allow you to reference the object having this type from the
647   TYPE node, i.e. without having a variable instantiating this type.
648
649   Such a "self-references" is done using a PLACEHOLDER_EXPR.  This is
650   a node that will later be replaced with the object being referenced.
651   Its type is that of the object and selects which object to use from
652   a chain of references (see below).  No other slots are used in the
653   PLACEHOLDER_EXPR.
654
655   For example, if your type FOO is a RECORD_TYPE with a field BAR,
656   and you need the value of <variable>.BAR to calculate TYPE_SIZE
657   (FOO), just substitute <variable> above with a PLACEHOLDER_EXPR
658   whose TREE_TYPE is FOO.  Then construct your COMPONENT_REF with
659   the PLACEHOLDER_EXPR as the first operand (which has the correct
660   type).  Later, when the size is needed in the program, the back-end
661   will find this PLACEHOLDER_EXPR and generate code to calculate the
662   actual size at run-time.  In the following, we describe how this
663   calculation is done.
664
665   When we wish to evaluate a size or offset, we check whether it contains a
666   PLACEHOLDER_EXPR.  If it does, we call substitute_placeholder_in_expr
667   passing both that tree and an expression within which the object may be
668   found.  The latter expression is the object itself in the simple case of
669   an Ada record with discriminant, but it can be the array in the case of an
670   unconstrained array.
671
672   In the latter case, we need the fat pointer, because the bounds of
673   the array can only be accessed from it.  However, we rely here on the
674   fact that the expression for the array contains the dereference of
675   the fat pointer that obtained the array pointer.  */
676
677/* Denotes a record to later be substituted before evaluating this expression.
678   The type of this expression is used to find the record to replace it.  */
679DEFTREECODE (PLACEHOLDER_EXPR, "placeholder_expr", tcc_exceptional, 0)
680
681/* Simple arithmetic.  */
682DEFTREECODE (PLUS_EXPR, "plus_expr", tcc_binary, 2)
683DEFTREECODE (MINUS_EXPR, "minus_expr", tcc_binary, 2)
684DEFTREECODE (MULT_EXPR, "mult_expr", tcc_binary, 2)
685
686/* Pointer addition.  The first operand is always a pointer and the
687   second operand is an integer of type sizetype.  */
688DEFTREECODE (POINTER_PLUS_EXPR, "pointer_plus_expr", tcc_binary, 2)
689
690/* Pointer subtraction.  The two arguments are pointers, and the result
691   is a signed integer of the same precision.  Pointers are interpreted
692   as unsigned, the difference is computed as if in infinite signed
693   precision.  Behavior is undefined if the difference does not fit in
694   the result type.  The result does not depend on the pointer type,
695   it is not divided by the size of the pointed-to type.  */
696DEFTREECODE (POINTER_DIFF_EXPR, "pointer_diff_expr", tcc_binary, 2)
697
698/* Highpart multiplication.  For an integral type with precision B,
699   returns bits [2B-1, B] of the full 2*B product.  */
700DEFTREECODE (MULT_HIGHPART_EXPR, "mult_highpart_expr", tcc_binary, 2)
701
702/* Division for integer result that rounds the quotient toward zero.  */
703DEFTREECODE (TRUNC_DIV_EXPR, "trunc_div_expr", tcc_binary, 2)
704
705/* Division for integer result that rounds it toward plus infinity.  */
706DEFTREECODE (CEIL_DIV_EXPR, "ceil_div_expr", tcc_binary, 2)
707
708/* Division for integer result that rounds it toward minus infinity.  */
709DEFTREECODE (FLOOR_DIV_EXPR, "floor_div_expr", tcc_binary, 2)
710
711/* Division for integer result that rounds it toward nearest integer.  */
712DEFTREECODE (ROUND_DIV_EXPR, "round_div_expr", tcc_binary, 2)
713
714/* Four kinds of remainder that go with the four kinds of division:  */
715
716/* The sign of the remainder is that of the dividend.  */
717DEFTREECODE (TRUNC_MOD_EXPR, "trunc_mod_expr", tcc_binary, 2)
718
719/* The sign of the remainder is the opposite of that of the divisor.  */
720DEFTREECODE (CEIL_MOD_EXPR, "ceil_mod_expr", tcc_binary, 2)
721
722/* The sign of the remainder is that of the divisor.  */
723DEFTREECODE (FLOOR_MOD_EXPR, "floor_mod_expr", tcc_binary, 2)
724
725/* The sign of the remainder is not predictable.  */
726DEFTREECODE (ROUND_MOD_EXPR, "round_mod_expr", tcc_binary, 2)
727
728/* Division for real result.  */
729DEFTREECODE (RDIV_EXPR, "rdiv_expr", tcc_binary, 2)
730
731/* Division which is not supposed to need rounding.
732   Used for pointer subtraction in C.  */
733DEFTREECODE (EXACT_DIV_EXPR, "exact_div_expr", tcc_binary, 2)
734
735/* Conversion of real to fixed point by truncation.  */
736DEFTREECODE (FIX_TRUNC_EXPR, "fix_trunc_expr", tcc_unary, 1)
737
738/* Conversion of an integer to a real.  */
739DEFTREECODE (FLOAT_EXPR, "float_expr", tcc_unary, 1)
740
741/* Unary negation.  */
742DEFTREECODE (NEGATE_EXPR, "negate_expr", tcc_unary, 1)
743
744/* Minimum and maximum values.  When used with floating point, if both
745   operands are zeros, or if either operand is NaN, then it is unspecified
746   which of the two operands is returned as the result.  */
747DEFTREECODE (MIN_EXPR, "min_expr", tcc_binary, 2)
748DEFTREECODE (MAX_EXPR, "max_expr", tcc_binary, 2)
749
750/* Represents the absolute value of the operand.
751
752   An ABS_EXPR must have either an INTEGER_TYPE or a REAL_TYPE.  The
753   operand of the ABS_EXPR must have the same type.  */
754DEFTREECODE (ABS_EXPR, "abs_expr", tcc_unary, 1)
755
756/* Represents the unsigned absolute value of the operand.
757   An ABSU_EXPR must have unsigned INTEGER_TYPE.  The operand of the ABSU_EXPR
758   must have the corresponding signed type.  */
759DEFTREECODE (ABSU_EXPR, "absu_expr", tcc_unary, 1)
760
761/* Shift operations for shift and rotate.
762   Shift means logical shift if done on an
763   unsigned type, arithmetic shift if done on a signed type.
764   The second operand is the number of bits to
765   shift by; it need not be the same type as the first operand and result.
766   Note that the result is undefined if the second operand is larger
767   than or equal to the first operand's type size.
768
769   The first operand of a shift can have either an integer or a
770   (non-integer) fixed-point type.  We follow the ISO/IEC TR 18037:2004
771   semantics for the latter.
772
773   Rotates are defined for integer types only.  */
774DEFTREECODE (LSHIFT_EXPR, "lshift_expr", tcc_binary, 2)
775DEFTREECODE (RSHIFT_EXPR, "rshift_expr", tcc_binary, 2)
776DEFTREECODE (LROTATE_EXPR, "lrotate_expr", tcc_binary, 2)
777DEFTREECODE (RROTATE_EXPR, "rrotate_expr", tcc_binary, 2)
778
779/* Bitwise operations.  Operands have same mode as result.  */
780DEFTREECODE (BIT_IOR_EXPR, "bit_ior_expr", tcc_binary, 2)
781DEFTREECODE (BIT_XOR_EXPR, "bit_xor_expr", tcc_binary, 2)
782DEFTREECODE (BIT_AND_EXPR, "bit_and_expr", tcc_binary, 2)
783DEFTREECODE (BIT_NOT_EXPR, "bit_not_expr", tcc_unary, 1)
784
785/* ANDIF and ORIF allow the second operand not to be computed if the
786   value of the expression is determined from the first operand.  AND,
787   OR, and XOR always compute the second operand whether its value is
788   needed or not (for side effects).  The operand may have
789   BOOLEAN_TYPE or INTEGER_TYPE.  In either case, the argument will be
790   either zero or one.  For example, a TRUTH_NOT_EXPR will never have
791   an INTEGER_TYPE VAR_DECL as its argument; instead, a NE_EXPR will be
792   used to compare the VAR_DECL to zero, thereby obtaining a node with
793   value zero or one.  */
794DEFTREECODE (TRUTH_ANDIF_EXPR, "truth_andif_expr", tcc_expression, 2)
795DEFTREECODE (TRUTH_ORIF_EXPR, "truth_orif_expr", tcc_expression, 2)
796DEFTREECODE (TRUTH_AND_EXPR, "truth_and_expr", tcc_expression, 2)
797DEFTREECODE (TRUTH_OR_EXPR, "truth_or_expr", tcc_expression, 2)
798DEFTREECODE (TRUTH_XOR_EXPR, "truth_xor_expr", tcc_expression, 2)
799DEFTREECODE (TRUTH_NOT_EXPR, "truth_not_expr", tcc_expression, 1)
800
801/* Relational operators.
802   EQ_EXPR and NE_EXPR are allowed for any types.  The others, except for
803   LTGT_EXPR, are allowed only for integral, floating-point and vector types.
804   LTGT_EXPR is allowed only for floating-point types.
805   For floating-point operators, if either operand is a NaN, then NE_EXPR
806   returns true and the remaining operators return false.  The operators
807   other than EQ_EXPR and NE_EXPR may generate an exception on quiet NaNs.
808   In all cases the operands will have the same type,
809   and the value is either the type used by the language for booleans
810   or an integer vector type of the same size and with the same number
811   of elements as the comparison operands.  True for a vector of
812   comparison results has all bits set while false is equal to zero.  */
813DEFTREECODE (LT_EXPR, "lt_expr", tcc_comparison, 2)
814DEFTREECODE (LE_EXPR, "le_expr", tcc_comparison, 2)
815DEFTREECODE (GT_EXPR, "gt_expr", tcc_comparison, 2)
816DEFTREECODE (GE_EXPR, "ge_expr", tcc_comparison, 2)
817DEFTREECODE (LTGT_EXPR, "ltgt_expr", tcc_comparison, 2)
818DEFTREECODE (EQ_EXPR, "eq_expr", tcc_comparison, 2)
819DEFTREECODE (NE_EXPR, "ne_expr", tcc_comparison, 2)
820
821/* Additional relational operators for floating-point unordered.  */
822DEFTREECODE (UNORDERED_EXPR, "unordered_expr", tcc_comparison, 2)
823DEFTREECODE (ORDERED_EXPR, "ordered_expr", tcc_comparison, 2)
824
825/* These are equivalent to unordered or ...  */
826DEFTREECODE (UNLT_EXPR, "unlt_expr", tcc_comparison, 2)
827DEFTREECODE (UNLE_EXPR, "unle_expr", tcc_comparison, 2)
828DEFTREECODE (UNGT_EXPR, "ungt_expr", tcc_comparison, 2)
829DEFTREECODE (UNGE_EXPR, "unge_expr", tcc_comparison, 2)
830DEFTREECODE (UNEQ_EXPR, "uneq_expr", tcc_comparison, 2)
831
832DEFTREECODE (RANGE_EXPR, "range_expr", tcc_binary, 2)
833
834/* Represents a re-association barrier for floating point expressions
835   like explicit parenthesis in fortran.  */
836DEFTREECODE (PAREN_EXPR, "paren_expr", tcc_unary, 1)
837
838/* Represents a conversion of type of a value.
839   All conversions, including implicit ones, must be
840   represented by CONVERT_EXPR or NOP_EXPR nodes.  */
841DEFTREECODE (CONVERT_EXPR, "convert_expr", tcc_unary, 1)
842
843/* Conversion of a pointer value to a pointer to a different
844   address space.  */
845DEFTREECODE (ADDR_SPACE_CONVERT_EXPR, "addr_space_convert_expr", tcc_unary, 1)
846
847/* Conversion of a fixed-point value to an integer, a real, or a fixed-point
848   value.  Or conversion of a fixed-point value from an integer, a real, or
849   a fixed-point value.  */
850DEFTREECODE (FIXED_CONVERT_EXPR, "fixed_convert_expr", tcc_unary, 1)
851
852/* Represents a conversion expected to require no code to be generated.  */
853DEFTREECODE (NOP_EXPR, "nop_expr", tcc_unary, 1)
854
855/* Value is same as argument, but guaranteed not an lvalue.  */
856DEFTREECODE (NON_LVALUE_EXPR, "non_lvalue_expr", tcc_unary, 1)
857
858/* A COMPOUND_LITERAL_EXPR represents a literal that is placed in a DECL.  The
859   COMPOUND_LITERAL_EXPR_DECL_EXPR is the a DECL_EXPR containing the decl
860   for the anonymous object represented by the COMPOUND_LITERAL;
861   the DECL_INITIAL of that decl is the CONSTRUCTOR that initializes
862   the compound literal.  */
863DEFTREECODE (COMPOUND_LITERAL_EXPR, "compound_literal_expr", tcc_expression, 1)
864
865/* Represents something we computed once and will use multiple times.
866   First operand is that expression.  After it is evaluated once, it
867   will be replaced by the temporary variable that holds the value.  */
868DEFTREECODE (SAVE_EXPR, "save_expr", tcc_expression, 1)
869
870/* & in C.  Value is the address at which the operand's value resides.
871   Operand may have any mode.  Result mode is Pmode.  */
872DEFTREECODE (ADDR_EXPR, "addr_expr", tcc_expression, 1)
873
874/* Operand0 is a function constant; result is part N of a function
875   descriptor of type ptr_mode.  */
876DEFTREECODE (FDESC_EXPR, "fdesc_expr", tcc_expression, 2)
877
878/* Given a container value, a replacement value and a bit position within
879   the container, produce the value that results from replacing the part of
880   the container starting at the bit position with the replacement value.
881   Operand 0 is a tree for the container value of integral or vector type;
882   Operand 1 is a tree for the replacement value of another integral or
883   the vector element type;
884   Operand 2 is a tree giving the constant bit position;
885   The number of bits replaced is given by the precision of the type of the
886   replacement value if it is integral or by its size if it is non-integral.
887   ???  The reason to make the size of the replacement implicit is to avoid
888   introducing a quaternary operation.
889   The replaced bits shall be fully inside the container.  If the container
890   is of vector type, then these bits shall be aligned with its elements.  */
891DEFTREECODE (BIT_INSERT_EXPR, "bit_insert_expr", tcc_expression, 3)
892
893/* Given two real or integer operands of the same type,
894   returns a complex value of the corresponding complex type.  */
895DEFTREECODE (COMPLEX_EXPR, "complex_expr", tcc_binary, 2)
896
897/* Complex conjugate of operand.  Used only on complex types.  */
898DEFTREECODE (CONJ_EXPR, "conj_expr", tcc_unary, 1)
899
900/* Nodes for ++ and -- in C.
901   The second arg is how much to increment or decrement by.
902   For a pointer, it would be the size of the object pointed to.  */
903DEFTREECODE (PREDECREMENT_EXPR, "predecrement_expr", tcc_expression, 2)
904DEFTREECODE (PREINCREMENT_EXPR, "preincrement_expr", tcc_expression, 2)
905DEFTREECODE (POSTDECREMENT_EXPR, "postdecrement_expr", tcc_expression, 2)
906DEFTREECODE (POSTINCREMENT_EXPR, "postincrement_expr", tcc_expression, 2)
907
908/* Used to implement `va_arg'.  */
909DEFTREECODE (VA_ARG_EXPR, "va_arg_expr", tcc_expression, 1)
910
911/* Evaluate operand 0.  If and only if an exception is thrown during
912   the evaluation of operand 0, evaluate operand 1.
913
914   This differs from TRY_FINALLY_EXPR in that operand 1 is not evaluated
915   on a normal or jump exit, only on an exception.  */
916DEFTREECODE (TRY_CATCH_EXPR, "try_catch_expr", tcc_statement, 2)
917
918/* Evaluate the first operand.
919   The second operand is a cleanup expression which is evaluated
920   on any exit (normal, exception, or jump out) from this expression.  */
921DEFTREECODE (TRY_FINALLY_EXPR, "try_finally_expr", tcc_statement, 2)
922
923/* Evaluate either the normal or the exceptional cleanup.  This must
924   only be present as the cleanup expression in a TRY_FINALLY_EXPR.
925   If the TRY_FINALLY_EXPR completes normally, the first operand of
926   EH_ELSE_EXPR is used as a cleanup, otherwise the second operand is
927   used.  */
928DEFTREECODE (EH_ELSE_EXPR, "eh_else_expr", tcc_statement, 2)
929
930/* These types of expressions have no useful value,
931   and always have side effects.  */
932
933/* Used to represent a local declaration. The operand is DECL_EXPR_DECL.  */
934DEFTREECODE (DECL_EXPR, "decl_expr", tcc_statement, 1)
935
936/* A label definition, encapsulated as a statement.
937   Operand 0 is the LABEL_DECL node for the label that appears here.
938   The type should be void and the value should be ignored.  */
939DEFTREECODE (LABEL_EXPR, "label_expr", tcc_statement, 1)
940
941/* GOTO.  Operand 0 is a LABEL_DECL node or an expression.
942   The type should be void and the value should be ignored.  */
943DEFTREECODE (GOTO_EXPR, "goto_expr", tcc_statement, 1)
944
945/* RETURN.  Evaluates operand 0, then returns from the current function.
946   Presumably that operand is an assignment that stores into the
947   RESULT_DECL that hold the value to be returned.
948   The operand may be null.
949   The type should be void and the value should be ignored.  */
950DEFTREECODE (RETURN_EXPR, "return_expr", tcc_statement, 1)
951
952/* Exit the inner most loop conditionally.  Operand 0 is the condition.
953   The type should be void and the value should be ignored.  */
954DEFTREECODE (EXIT_EXPR, "exit_expr", tcc_statement, 1)
955
956/* A loop.  Operand 0 is the body of the loop.
957   It must contain an EXIT_EXPR or is an infinite loop.
958   The type should be void and the value should be ignored.  */
959DEFTREECODE (LOOP_EXPR, "loop_expr", tcc_statement, 1)
960
961/* Switch expression.
962
963   TREE_TYPE is the original type of the condition, before any
964   language required type conversions.  It may be NULL, in which case
965   the original type and final types are assumed to be the same.
966
967   Operand 0 is the expression used to perform the branch,
968   Operand 1 is the body of the switch, which probably contains
969     CASE_LABEL_EXPRs.  It may also be NULL, in which case operand 2
970     must not be NULL.  */
971DEFTREECODE (SWITCH_EXPR, "switch_expr", tcc_statement, 2)
972
973/* Used to represent a case label.
974
975   Operand 0 is CASE_LOW.  It may be NULL_TREE, in which case the label
976     is a 'default' label.
977   Operand 1 is CASE_HIGH.  If it is NULL_TREE, the label is a simple
978     (one-value) case label.  If it is non-NULL_TREE, the case is a range.
979   Operand 2 is CASE_LABEL, which has the corresponding LABEL_DECL.
980   Operand 3 is CASE_CHAIN.  This operand is only used in tree-cfg.c to
981     speed up the lookup of case labels which use a particular edge in
982     the control flow graph.  */
983DEFTREECODE (CASE_LABEL_EXPR, "case_label_expr", tcc_statement, 4)
984
985/* Used to represent an inline assembly statement.  ASM_STRING returns a
986   STRING_CST for the instruction (e.g., "mov x, y"). ASM_OUTPUTS,
987   ASM_INPUTS, and ASM_CLOBBERS represent the outputs, inputs, and clobbers
988   for the statement.  ASM_LABELS, if present, indicates various destinations
989   for the asm; labels cannot be combined with outputs.  */
990DEFTREECODE (ASM_EXPR, "asm_expr", tcc_statement, 5)
991
992/* Variable references for SSA analysis.  New SSA names are created every
993   time a variable is assigned a new value.  The SSA builder uses SSA_NAME
994   nodes to implement SSA versioning.  */
995DEFTREECODE (SSA_NAME, "ssa_name", tcc_exceptional, 0)
996
997/* Used to represent a typed exception handler.  CATCH_TYPES is the type (or
998   list of types) handled, and CATCH_BODY is the code for the handler.  */
999DEFTREECODE (CATCH_EXPR, "catch_expr", tcc_statement, 2)
1000
1001/* Used to represent an exception specification.  EH_FILTER_TYPES is a list
1002   of allowed types, and EH_FILTER_FAILURE is an expression to evaluate on
1003   failure.  */
1004DEFTREECODE (EH_FILTER_EXPR, "eh_filter_expr", tcc_statement, 2)
1005
1006/* Node used for describing a property that is known at compile
1007   time.  */
1008DEFTREECODE (SCEV_KNOWN, "scev_known", tcc_expression, 0)
1009
1010/* Node used for describing a property that is not known at compile
1011   time.  */
1012DEFTREECODE (SCEV_NOT_KNOWN, "scev_not_known", tcc_expression, 0)
1013
1014/* Polynomial chains of recurrences.
1015   cr = {CHREC_LEFT (cr), +, CHREC_RIGHT (cr)}_CHREC_VARIABLE (cr).  */
1016DEFTREECODE (POLYNOMIAL_CHREC, "polynomial_chrec", tcc_expression, 2)
1017
1018/* Used to chain children of container statements together.
1019   Use the interface in tree-iterator.h to access this node.  */
1020DEFTREECODE (STATEMENT_LIST, "statement_list", tcc_exceptional, 0)
1021
1022/* Predicate assertion.  Artificial expression generated by the optimizers
1023   to keep track of predicate values.  This expression may only appear on
1024   the RHS of assignments.
1025
1026   Given X = ASSERT_EXPR <Y, EXPR>, the optimizers can infer
1027   two things:
1028
1029   	1- X is a copy of Y.
1030	2- EXPR is a conditional expression and is known to be true.
1031
1032   Valid and to be expected forms of conditional expressions are
1033   valid GIMPLE conditional expressions (as defined by is_gimple_condexpr)
1034   and conditional expressions with the first operand being a
1035   PLUS_EXPR with a variable possibly wrapped in a NOP_EXPR first
1036   operand and an integer constant second operand.
1037
1038   The type of the expression is the same as Y.  */
1039DEFTREECODE (ASSERT_EXPR, "assert_expr", tcc_expression, 2)
1040
1041/* Base class information. Holds information about a class as a
1042   baseclass of itself or another class.  */
1043DEFTREECODE (TREE_BINFO, "tree_binfo", tcc_exceptional, 0)
1044
1045/* Records the size for an expression of variable size type.  This is
1046   for use in contexts in which we are accessing the entire object,
1047   such as for a function call, or block copy.
1048   Operand 0 is the real expression.
1049   Operand 1 is the size of the type in the expression.  */
1050DEFTREECODE (WITH_SIZE_EXPR, "with_size_expr", tcc_expression, 2)
1051
1052/* Extract elements from two input vectors Operand 0 and Operand 1
1053   size VS, according to the offset OFF defined by Operand 2 as
1054   follows:
1055   If OFF > 0, the last VS - OFF elements of vector OP0 are concatenated to
1056   the first OFF elements of the vector OP1.
1057   If OFF == 0, then the returned vector is OP1.
1058   On different targets OFF may take different forms; It can be an address, in
1059   which case its low log2(VS)-1 bits define the offset, or it can be a mask
1060   generated by the builtin targetm.vectorize.mask_for_load_builtin_decl.  */
1061DEFTREECODE (REALIGN_LOAD_EXPR, "realign_load", tcc_expression, 3)
1062
1063/* Low-level memory addressing.  Operands are BASE (address of static or
1064   global variable or register), OFFSET (integer constant),
1065   INDEX (register), STEP (integer constant), INDEX2 (register),
1066   The corresponding address is BASE + STEP * INDEX + INDEX2 + OFFSET.
1067   Only variations and values valid on the target are allowed.
1068
1069   The type of STEP, INDEX and INDEX2 is sizetype.
1070
1071   The type of BASE is a pointer type.  If BASE is not an address of
1072   a static or global variable INDEX2 will be NULL.
1073
1074   The type of OFFSET is a pointer type and determines TBAA the same as
1075   the constant offset operand in MEM_REF.  */
1076
1077DEFTREECODE (TARGET_MEM_REF, "target_mem_ref", tcc_reference, 5)
1078
1079/* Memory addressing.  Operands are a pointer and a tree constant integer
1080   byte offset of the pointer type that when dereferenced yields the
1081   type of the base object the pointer points into and which is used for
1082   TBAA purposes.
1083   The type of the MEM_REF is the type the bytes at the memory location
1084   are interpreted as.
1085   MEM_REF <p, c> is equivalent to ((typeof(c))p)->x... where x... is a
1086   chain of component references offsetting p by c.  */
1087DEFTREECODE (MEM_REF, "mem_ref", tcc_reference, 2)
1088
1089/* OpenACC and OpenMP.  As it is exposed in TREE_RANGE_CHECK invocations, do
1090   not change the ordering of these codes.  */
1091
1092/* OpenACC - #pragma acc parallel [clause1 ... clauseN]
1093   Operand 0: OMP_BODY: Code to be executed in parallel.
1094   Operand 1: OMP_CLAUSES: List of clauses.  */
1095
1096DEFTREECODE (OACC_PARALLEL, "oacc_parallel", tcc_statement, 2)
1097
1098/* OpenACC - #pragma acc kernels [clause1 ... clauseN]
1099   Operand 0: OMP_BODY: Sequence of kernels.
1100   Operand 1: OMP_CLAUSES: List of clauses.  */
1101
1102DEFTREECODE (OACC_KERNELS, "oacc_kernels", tcc_statement, 2)
1103
1104/* OpenACC - #pragma acc serial [clause1 ... clauseN]
1105   Operand 0: OMP_BODY: Code to be executed sequentially.
1106   Operand 1: OMP_CLAUSES: List of clauses.  */
1107
1108DEFTREECODE (OACC_SERIAL, "oacc_serial", tcc_statement, 2)
1109
1110/* OpenACC - #pragma acc data [clause1 ... clauseN]
1111   Operand 0: OACC_DATA_BODY: Data construct body.
1112   Operand 1: OACC_DATA_CLAUSES: List of clauses.  */
1113
1114DEFTREECODE (OACC_DATA, "oacc_data", tcc_statement, 2)
1115
1116/* OpenACC - #pragma acc host_data [clause1 ... clauseN]
1117   Operand 0: OACC_HOST_DATA_BODY: Host_data construct body.
1118   Operand 1: OACC_HOST_DATA_CLAUSES: List of clauses.  */
1119
1120DEFTREECODE (OACC_HOST_DATA, "oacc_host_data", tcc_statement, 2)
1121
1122/* OpenMP - #pragma omp parallel [clause1 ... clauseN]
1123   Operand 0: OMP_PARALLEL_BODY: Code to be executed by all threads.
1124   Operand 1: OMP_PARALLEL_CLAUSES: List of clauses.  */
1125
1126DEFTREECODE (OMP_PARALLEL, "omp_parallel", tcc_statement, 2)
1127
1128/* OpenMP - #pragma omp task [clause1 ... clauseN]
1129   Operand 0: OMP_TASK_BODY: Code to be executed by all threads.
1130   Operand 1: OMP_TASK_CLAUSES: List of clauses.  */
1131
1132DEFTREECODE (OMP_TASK, "omp_task", tcc_statement, 2)
1133
1134/* OpenMP - #pragma omp for [clause1 ... clauseN]
1135   Operand 0: OMP_FOR_BODY: Loop body.
1136   Operand 1: OMP_FOR_CLAUSES: List of clauses.
1137   Operand 2: OMP_FOR_INIT: Initialization code of the form
1138                             	VAR = N1.
1139   Operand 3: OMP_FOR_COND: Loop conditional expression of the form
1140                             	VAR { <, >, <=, >= } N2.
1141   Operand 4: OMP_FOR_INCR: Loop index increment of the form
1142			     	VAR { +=, -= } INCR.
1143   Operand 5: OMP_FOR_PRE_BODY: Filled by the gimplifier with things
1144	from INIT, COND, and INCR that are technically part of the
1145	OMP_FOR structured block, but are evaluated before the loop
1146	body begins.
1147   Operand 6: OMP_FOR_ORIG_DECLS: If non-NULL, list of DECLs initialized
1148	in OMP_FOR_INIT.  In some cases, like C++ iterators, the original
1149	DECL init has been lost in gimplification and now contains a
1150	temporary (D.nnnn).  This list contains the original DECLs in
1151	the source.
1152
1153   VAR must be an integer or pointer variable, which is implicitly thread
1154   private.  N1, N2 and INCR are required to be loop invariant integer
1155   expressions that are evaluated without any synchronization.
1156   The evaluation order, frequency of evaluation and side-effects are
1157   unspecified by the standards.  */
1158DEFTREECODE (OMP_FOR, "omp_for", tcc_statement, 7)
1159
1160/* OpenMP - #pragma omp simd [clause1 ... clauseN]
1161   Operands like for OMP_FOR.  */
1162DEFTREECODE (OMP_SIMD, "omp_simd", tcc_statement, 7)
1163
1164/* OpenMP - #pragma omp distribute [clause1 ... clauseN]
1165   Operands like for OMP_FOR.  */
1166DEFTREECODE (OMP_DISTRIBUTE, "omp_distribute", tcc_statement, 7)
1167
1168/* OpenMP - #pragma omp taskloop [clause1 ... clauseN]
1169   Operands like for OMP_FOR.  */
1170DEFTREECODE (OMP_TASKLOOP, "omp_taskloop", tcc_statement, 7)
1171
1172/* OpenMP - #pragma omp loop [clause1 ... clauseN]
1173   Operands like for OMP_FOR.  */
1174DEFTREECODE (OMP_LOOP, "omp_loop", tcc_statement, 7)
1175
1176/* OpenMP - #pragma acc loop [clause1 ... clauseN]
1177   Operands like for OMP_FOR.  */
1178DEFTREECODE (OACC_LOOP, "oacc_loop", tcc_statement, 7)
1179
1180/* OpenMP - #pragma omp teams [clause1 ... clauseN]
1181   Operand 0: OMP_TEAMS_BODY: Teams body.
1182   Operand 1: OMP_TEAMS_CLAUSES: List of clauses.  */
1183DEFTREECODE (OMP_TEAMS, "omp_teams", tcc_statement, 2)
1184
1185/* OpenMP - #pragma omp target data [clause1 ... clauseN]
1186   Operand 0: OMP_TARGET_DATA_BODY: Target data construct body.
1187   Operand 1: OMP_TARGET_DATA_CLAUSES: List of clauses.  */
1188DEFTREECODE (OMP_TARGET_DATA, "omp_target_data", tcc_statement, 2)
1189
1190/* OpenMP - #pragma omp target [clause1 ... clauseN]
1191   Operand 0: OMP_TARGET_BODY: Target construct body.
1192   Operand 1: OMP_TARGET_CLAUSES: List of clauses.  */
1193DEFTREECODE (OMP_TARGET, "omp_target", tcc_statement, 2)
1194
1195/* OpenMP - #pragma omp sections [clause1 ... clauseN]
1196   Operand 0: OMP_SECTIONS_BODY: Sections body.
1197   Operand 1: OMP_SECTIONS_CLAUSES: List of clauses.  */
1198DEFTREECODE (OMP_SECTIONS, "omp_sections", tcc_statement, 2)
1199
1200/* OpenMP - #pragma omp ordered
1201   Operand 0: OMP_ORDERED_BODY: Master section body.
1202   Operand 1: OMP_ORDERED_CLAUSES: List of clauses.  */
1203DEFTREECODE (OMP_ORDERED, "omp_ordered", tcc_statement, 2)
1204
1205/* OpenMP - #pragma omp critical [name]
1206   Operand 0: OMP_CRITICAL_BODY: Critical section body.
1207   Operand 1: OMP_CRITICAL_CLAUSES: List of clauses.
1208   Operand 2: OMP_CRITICAL_NAME: Identifier for critical section.  */
1209DEFTREECODE (OMP_CRITICAL, "omp_critical", tcc_statement, 3)
1210
1211/* OpenMP - #pragma omp single
1212   Operand 0: OMP_SINGLE_BODY: Single section body.
1213   Operand 1: OMP_SINGLE_CLAUSES: List of clauses.  */
1214DEFTREECODE (OMP_SINGLE, "omp_single", tcc_statement, 2)
1215
1216/* OpenMP - #pragma omp taskgroup
1217   Operand 0: OMP_TASKGROUP_BODY: Taskgroup body.
1218   Operand 1: OMP_SINGLE_CLAUSES: List of clauses.  */
1219DEFTREECODE (OMP_TASKGROUP, "omp_taskgroup", tcc_statement, 2)
1220
1221/* OpenMP - #pragma omp scan
1222   Operand 0: OMP_SCAN_BODY: Scan body.
1223   Operand 1: OMP_SCAN_CLAUSES: List of clauses.  */
1224DEFTREECODE (OMP_SCAN, "omp_scan", tcc_statement, 2)
1225
1226/* OpenMP - #pragma omp section
1227   Operand 0: OMP_SECTION_BODY: Section body.  */
1228DEFTREECODE (OMP_SECTION, "omp_section", tcc_statement, 1)
1229
1230/* OpenMP - #pragma omp master
1231   Operand 0: OMP_MASTER_BODY: Master section body.  */
1232DEFTREECODE (OMP_MASTER, "omp_master", tcc_statement, 1)
1233
1234/* OpenACC - #pragma acc cache (variable1 ... variableN)
1235   Operand 0: OACC_CACHE_CLAUSES: List of variables (transformed into
1236	OMP_CLAUSE__CACHE_ clauses).  */
1237DEFTREECODE (OACC_CACHE, "oacc_cache", tcc_statement, 1)
1238
1239/* OpenACC - #pragma acc declare [clause1 ... clauseN]
1240   Operand 0: OACC_DECLARE_CLAUSES: List of clauses.  */
1241DEFTREECODE (OACC_DECLARE, "oacc_declare", tcc_statement, 1)
1242
1243/* OpenACC - #pragma acc enter data [clause1 ... clauseN]
1244   Operand 0: OACC_ENTER_DATA_CLAUSES: List of clauses.  */
1245DEFTREECODE (OACC_ENTER_DATA, "oacc_enter_data", tcc_statement, 1)
1246
1247/* OpenACC - #pragma acc exit data [clause1 ... clauseN]
1248   Operand 0: OACC_EXIT_DATA_CLAUSES: List of clauses.  */
1249DEFTREECODE (OACC_EXIT_DATA, "oacc_exit_data", tcc_statement, 1)
1250
1251/* OpenACC - #pragma acc update [clause1 ... clauseN]
1252   Operand 0: OACC_UPDATE_CLAUSES: List of clauses.  */
1253DEFTREECODE (OACC_UPDATE, "oacc_update", tcc_statement, 1)
1254
1255/* OpenMP - #pragma omp target update [clause1 ... clauseN]
1256   Operand 0: OMP_TARGET_UPDATE_CLAUSES: List of clauses.  */
1257DEFTREECODE (OMP_TARGET_UPDATE, "omp_target_update", tcc_statement, 1)
1258
1259/* OpenMP - #pragma omp target enter data [clause1 ... clauseN]
1260   Operand 0: OMP_TARGET_ENTER_DATA_CLAUSES: List of clauses.  */
1261DEFTREECODE (OMP_TARGET_ENTER_DATA, "omp_target_enter_data", tcc_statement, 1)
1262
1263/* OpenMP - #pragma omp target exit data [clause1 ... clauseN]
1264   Operand 0: OMP_TARGET_EXIT_DATA_CLAUSES: List of clauses.  */
1265DEFTREECODE (OMP_TARGET_EXIT_DATA, "omp_target_exit_data", tcc_statement, 1)
1266
1267/* OMP_ATOMIC through OMP_ATOMIC_CAPTURE_NEW must be consecutive,
1268   or OMP_ATOMIC_SEQ_CST needs adjusting.  */
1269
1270/* OpenMP - #pragma omp atomic
1271   Operand 0: The address at which the atomic operation is to be performed.
1272	This address should be stabilized with save_expr.
1273   Operand 1: The expression to evaluate.  When the old value of the object
1274	at the address is used in the expression, it should appear as if
1275	build_fold_indirect_ref of the address.  */
1276DEFTREECODE (OMP_ATOMIC, "omp_atomic", tcc_statement, 2)
1277
1278/* OpenMP - #pragma omp atomic read
1279   Operand 0: The address at which the atomic operation is to be performed.
1280	This address should be stabilized with save_expr.  */
1281DEFTREECODE (OMP_ATOMIC_READ, "omp_atomic_read", tcc_statement, 1)
1282
1283/* OpenMP - #pragma omp atomic capture
1284   Operand 0: The address at which the atomic operation is to be performed.
1285	This address should be stabilized with save_expr.
1286   Operand 1: The expression to evaluate.  When the old value of the object
1287	at the address is used in the expression, it should appear as if
1288	build_fold_indirect_ref of the address.
1289   OMP_ATOMIC_CAPTURE_OLD returns the old memory content,
1290   OMP_ATOMIC_CAPTURE_NEW the new value.  */
1291DEFTREECODE (OMP_ATOMIC_CAPTURE_OLD, "omp_atomic_capture_old", tcc_statement, 2)
1292DEFTREECODE (OMP_ATOMIC_CAPTURE_NEW, "omp_atomic_capture_new", tcc_statement, 2)
1293
1294/* OpenMP clauses.  */
1295DEFTREECODE (OMP_CLAUSE, "omp_clause", tcc_exceptional, 0)
1296
1297/* TRANSACTION_EXPR tree code.
1298   Operand 0: BODY: contains body of the transaction.  */
1299DEFTREECODE (TRANSACTION_EXPR, "transaction_expr", tcc_expression, 1)
1300
1301/* Widening dot-product.
1302   The first two arguments are of type t1.
1303   The third argument and the result are of type t2, such that t2 is at least
1304   twice the size of t1. DOT_PROD_EXPR(arg1,arg2,arg3) is equivalent to:
1305   	tmp = WIDEN_MULT_EXPR(arg1, arg2);
1306   	arg3 = PLUS_EXPR (tmp, arg3);
1307   or:
1308	tmp = WIDEN_MULT_EXPR(arg1, arg2);
1309        arg3 = WIDEN_SUM_EXPR (tmp, arg3);		 */
1310DEFTREECODE (DOT_PROD_EXPR, "dot_prod_expr", tcc_expression, 3)
1311
1312/* Widening summation.
1313   The first argument is of type t1.
1314   The second argument is of type t2, such that t2 is at least twice
1315   the size of t1. The type of the entire expression is also t2.
1316   WIDEN_SUM_EXPR is equivalent to first widening (promoting)
1317   the first argument from type t1 to type t2, and then summing it
1318   with the second argument.  */
1319DEFTREECODE (WIDEN_SUM_EXPR, "widen_sum_expr", tcc_binary, 2)
1320
1321/* Widening sad (sum of absolute differences).
1322   The first two arguments are of type t1 which should be integer.
1323   The third argument and the result are of type t2, such that t2 is at least
1324   twice the size of t1.  Like DOT_PROD_EXPR, SAD_EXPR (arg1,arg2,arg3) is
1325   equivalent to (note we don't have WIDEN_MINUS_EXPR now, but we assume its
1326   behavior is similar to WIDEN_SUM_EXPR):
1327       tmp = WIDEN_MINUS_EXPR (arg1, arg2)
1328       tmp2 = ABS_EXPR (tmp)
1329       arg3 = PLUS_EXPR (tmp2, arg3)
1330  or:
1331       tmp = WIDEN_MINUS_EXPR (arg1, arg2)
1332       tmp2 = ABS_EXPR (tmp)
1333       arg3 = WIDEN_SUM_EXPR (tmp2, arg3)
1334 */
1335DEFTREECODE (SAD_EXPR, "sad_expr", tcc_expression, 3)
1336
1337/* Widening multiplication.
1338   The two arguments are of type t1.
1339   The result is of type t2, such that t2 is at least twice
1340   the size of t1. WIDEN_MULT_EXPR is equivalent to first widening (promoting)
1341   the arguments from type t1 to type t2, and then multiplying them.  */
1342DEFTREECODE (WIDEN_MULT_EXPR, "widen_mult_expr", tcc_binary, 2)
1343
1344/* Widening multiply-accumulate.
1345   The first two arguments are of type t1.
1346   The third argument and the result are of type t2, such as t2 is at least
1347   twice the size of t1.  t1 and t2 must be integral or fixed-point types.
1348   The expression is equivalent to a WIDEN_MULT_EXPR operation
1349   of the first two operands followed by an add or subtract of the third
1350   operand.  */
1351DEFTREECODE (WIDEN_MULT_PLUS_EXPR, "widen_mult_plus_expr", tcc_expression, 3)
1352/* This is like the above, except in the final expression the multiply result
1353   is subtracted from t3.  */
1354DEFTREECODE (WIDEN_MULT_MINUS_EXPR, "widen_mult_minus_expr", tcc_expression, 3)
1355
1356/* Widening shift left.
1357   The first operand is of type t1.
1358   The second operand is the number of bits to shift by; it need not be the
1359   same type as the first operand and result.
1360   Note that the result is undefined if the second operand is larger
1361   than or equal to the first operand's type size.
1362   The type of the entire expression is t2, such that t2 is at least twice
1363   the size of t1.
1364   WIDEN_LSHIFT_EXPR is equivalent to first widening (promoting)
1365   the first argument from type t1 to type t2, and then shifting it
1366   by the second argument.  */
1367DEFTREECODE (WIDEN_LSHIFT_EXPR, "widen_lshift_expr", tcc_binary, 2)
1368DEFTREECODE (WIDEN_PLUS_EXPR, "widen_plus_expr", tcc_binary, 2)
1369DEFTREECODE (WIDEN_MINUS_EXPR, "widen_minus_expr", tcc_binary, 2)
1370
1371/* Widening vector multiplication.
1372   The two operands are vectors with N elements of size S. Multiplying the
1373   elements of the two vectors will result in N products of size 2*S.
1374   VEC_WIDEN_MULT_HI_EXPR computes the N/2 high products.
1375   VEC_WIDEN_MULT_LO_EXPR computes the N/2 low products.  */
1376DEFTREECODE (VEC_WIDEN_MULT_HI_EXPR, "widen_mult_hi_expr", tcc_binary, 2)
1377DEFTREECODE (VEC_WIDEN_MULT_LO_EXPR, "widen_mult_lo_expr", tcc_binary, 2)
1378
1379/* Similarly, but return the even or odd N/2 products.  */
1380DEFTREECODE (VEC_WIDEN_MULT_EVEN_EXPR, "widen_mult_even_expr", tcc_binary, 2)
1381DEFTREECODE (VEC_WIDEN_MULT_ODD_EXPR, "widen_mult_odd_expr", tcc_binary, 2)
1382
1383/* Unpack (extract and promote/widen) the high/low elements of the input
1384   vector into the output vector.  The input vector has twice as many
1385   elements as the output vector, that are half the size of the elements
1386   of the output vector.  This is used to support type promotion. */
1387DEFTREECODE (VEC_UNPACK_HI_EXPR, "vec_unpack_hi_expr", tcc_unary, 1)
1388DEFTREECODE (VEC_UNPACK_LO_EXPR, "vec_unpack_lo_expr", tcc_unary, 1)
1389
1390/* Unpack (extract) the high/low elements of the input vector, convert
1391   fixed point values to floating point and widen elements into the
1392   output vector.  The input vector has twice as many elements as the output
1393   vector, that are half the size of the elements of the output vector.  */
1394DEFTREECODE (VEC_UNPACK_FLOAT_HI_EXPR, "vec_unpack_float_hi_expr", tcc_unary, 1)
1395DEFTREECODE (VEC_UNPACK_FLOAT_LO_EXPR, "vec_unpack_float_lo_expr", tcc_unary, 1)
1396
1397/* Unpack (extract) the high/low elements of the input vector, convert
1398   floating point values to integer and widen elements into the output
1399   vector.  The input vector has twice as many elements as the output
1400   vector, that are half the size of the elements of the output vector.  */
1401DEFTREECODE (VEC_UNPACK_FIX_TRUNC_HI_EXPR, "vec_unpack_fix_trunc_hi_expr",
1402	     tcc_unary, 1)
1403DEFTREECODE (VEC_UNPACK_FIX_TRUNC_LO_EXPR, "vec_unpack_fix_trunc_lo_expr",
1404	     tcc_unary, 1)
1405
1406/* Pack (demote/narrow and merge) the elements of the two input vectors
1407   into the output vector using truncation/saturation.
1408   The elements of the input vectors are twice the size of the elements of the
1409   output vector.  This is used to support type demotion.  */
1410DEFTREECODE (VEC_PACK_TRUNC_EXPR, "vec_pack_trunc_expr", tcc_binary, 2)
1411DEFTREECODE (VEC_PACK_SAT_EXPR, "vec_pack_sat_expr", tcc_binary, 2)
1412
1413/* Convert floating point values of the two input vectors to integer
1414   and pack (narrow and merge) the elements into the output vector. The
1415   elements of the input vector are twice the size of the elements of
1416   the output vector.  */
1417DEFTREECODE (VEC_PACK_FIX_TRUNC_EXPR, "vec_pack_fix_trunc_expr", tcc_binary, 2)
1418
1419/* Convert fixed point values of the two input vectors to floating point
1420   and pack (narrow and merge) the elements into the output vector. The
1421   elements of the input vector are twice the size of the elements of
1422   the output vector.  */
1423DEFTREECODE (VEC_PACK_FLOAT_EXPR, "vec_pack_float_expr", tcc_binary, 2)
1424
1425/* Widening vector shift left in bits.
1426   Operand 0 is a vector to be shifted with N elements of size S.
1427   Operand 1 is an integer shift amount in bits.
1428   The result of the operation is N elements of size 2*S.
1429   VEC_WIDEN_LSHIFT_HI_EXPR computes the N/2 high results.
1430   VEC_WIDEN_LSHIFT_LO_EXPR computes the N/2 low results.
1431 */
1432DEFTREECODE (VEC_WIDEN_LSHIFT_HI_EXPR, "widen_lshift_hi_expr", tcc_binary, 2)
1433DEFTREECODE (VEC_WIDEN_LSHIFT_LO_EXPR, "widen_lshift_lo_expr", tcc_binary, 2)
1434DEFTREECODE (VEC_WIDEN_PLUS_HI_EXPR, "widen_plus_hi_expr", tcc_binary, 2)
1435DEFTREECODE (VEC_WIDEN_PLUS_LO_EXPR, "widen_plus_lo_expr", tcc_binary, 2)
1436DEFTREECODE (VEC_WIDEN_MINUS_HI_EXPR, "widen_minus_hi_expr", tcc_binary, 2)
1437DEFTREECODE (VEC_WIDEN_MINUS_LO_EXPR, "widen_minus_lo_expr", tcc_binary, 2)
1438
1439/* PREDICT_EXPR.  Specify hint for branch prediction.  The
1440   PREDICT_EXPR_PREDICTOR specify predictor and PREDICT_EXPR_OUTCOME the
1441   outcome (0 for not taken and 1 for taken).  Once the profile is guessed
1442   all conditional branches leading to execution paths executing the
1443   PREDICT_EXPR will get predicted by the specified predictor.  */
1444DEFTREECODE (PREDICT_EXPR, "predict_expr", tcc_expression, 1)
1445
1446/* OPTIMIZATION_NODE.  Node to store the optimization options.  */
1447DEFTREECODE (OPTIMIZATION_NODE, "optimization_node", tcc_exceptional, 0)
1448
1449/* TARGET_OPTION_NODE.  Node to store the target specific options.  */
1450DEFTREECODE (TARGET_OPTION_NODE, "target_option_node", tcc_exceptional, 0)
1451
1452/* ANNOTATE_EXPR.
1453   Operand 0 is the expression to be annotated.
1454   Operand 1 is the annotation kind.
1455   Operand 2 is additional data.  */
1456DEFTREECODE (ANNOTATE_EXPR, "annotate_expr", tcc_expression, 3)
1457
1458/*
1459Local variables:
1460mode:c
1461End:
1462*/
1463