Merge branch 'master' of ssh://crater.dragonflybsd.org/repository/git/dragonfly
[dragonfly.git] / contrib / gcc-3.4 / gcc / machmode.def
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1/* This file contains the definitions and documentation for the
2 machine modes used in the GNU compiler.
3 Copyright (C) 1987, 1992, 1994, 1997, 1998, 2000, 2003
4 Free Software Foundation, Inc.
5
6This file is part of GCC.
7
8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
10Software Foundation; either version 2, or (at your option) any later
11version.
12
13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16for more details.
17
18You should have received a copy of the GNU General Public License
19along with GCC; see the file COPYING. If not, write to the Free
20Software Foundation, 59 Temple Place - Suite 330, Boston, MA
2102111-1307, USA. */
22
23
24/* This file defines all the MACHINE MODES used by GCC.
25
26 A machine mode specifies a size and format of data
27 at the machine level.
28
29 Each RTL expression has a machine mode.
30
31 At the syntax tree level, each ..._TYPE and each ..._DECL node
32 has a machine mode which describes data of that type or the
33 data of the variable declared. */
34
35/* This file is included by the genmodes program. Its text is the
36 body of a function. Do not rely on this, it will change in the
37 future.
38
39 The following statements can be used in this file -- all have
40 the form of a C macro call. In their arguments:
41
42 A CLASS argument must be one of the constants defined in
43 mode-classes.def, less the leading MODE_ prefix; some statements
44 that take CLASS arguments have restructions on which classes are
45 acceptable. For instance, INT.
46
47 A MODE argument must be the printable name of a machine mode,
48 without quotation marks or trailing "mode". For instance, SI.
49
50 A PRECISION, BYTESIZE, or COUNT argument must be a positive integer
51 constant.
52
53 A FORMAT argument must be one of the real_mode_format structures
54 declared in real.h, or else a literal 0. Do not put a leading &
55 on the argument.
56
57 An EXPR argument must be a syntactically valid C expression.
58 If an EXPR contains commas, you may need to write an extra pair of
59 parentheses around it, so it appears to be a single argument to the
60 statement.
61
62 This file defines only those modes which are of use on almost all
63 machines. Other modes can be defined in the target-specific
64 mode definition file, config/ARCH/ARCH-modes.def.
65
66 Order matters in this file in so far as statements which refer to
67 other modes must appear after the modes they refer to. However,
68 statements which do not refer to other modes may appear in any
69 order.
70
71 RANDOM_MODE (MODE);
72 declares MODE to be of class RANDOM.
73
74 CC_MODE (MODE);
75 declares MODE to be of class CC.
76
77 INT_MODE (MODE, BYTESIZE);
78 declares MODE to be of class INT and BYTESIZE bytes wide.
79 All of the bits of its representation are significant.
80
81 FRACTIONAL_INT_MODE (MODE, PRECISION, BYTESIZE);
82 declares MODE to be of class INT, BYTESIZE bytes wide in
83 storage, but with only PRECISION significant bits.
84
85 FLOAT_MODE (MODE, BYTESIZE, FORMAT);
86 declares MODE to be of class FLOAT and BYTESIZE bytes wide,
87 using floating point format FORMAT.
88 All of the bits of its representation are significant.
89
90 FRACTIONAL_FLOAT_MODE (MODE, PRECISION, BYTESIZE, FORMAT);
91 declares MODE to be of class FLOAT, BYTESIZE bytes wide in
92 storage, but with only PRECISION significant bits, using
93 floating point format FORMAT.
94
95 RESET_FLOAT_FORMAT (MODE, FORMAT);
96 changes the format of MODE, which must be class FLOAT,
97 to FORMAT. Use in an ARCH-modes.def to reset the format
98 of one of the float modes defined in this file.
99
100 PARTIAL_INT_MODE (MODE);
101 declares a mode of class PARTIAL_INT with the same size as
102 MODE (which must be an INT mode). The name of the new mode
103 is made by prefixing a P to the name MODE. This statement
104 may grow a PRECISION argument in the future.
105
106 VECTOR_MODE (CLASS, MODE, COUNT);
107 Declare a vector mode whose component mode is MODE (of class
108 CLASS) with COUNT components. CLASS must be INT or FLOAT.
109 The name of the vector mode takes the form VnX where n is
110 COUNT in decimal and X is MODE.
111
112 VECTOR_MODES (CLASS, WIDTH);
113 For all modes presently declared in class CLASS, construct
114 corresponding vector modes having width WIDTH. Modes whose
115 byte sizes do not evenly divide WIDTH are ignored, as are
116 modes that would produce vector modes with only one component,
117 and modes smaller than one byte (if CLASS is INT) or smaller
118 than two bytes (if CLASS is FLOAT). CLASS must be INT or
119 FLOAT. The names follow the same rule as VECTOR_MODE uses.
120
121 COMPLEX_MODES (CLASS);
122 For all modes presently declared in class CLASS, construct
123 corresponding complex modes. Modes smaller than one byte
124 are ignored. For FLOAT modes, the names are derived by
125 replacing the 'F' in the mode name with a 'C'. (It is an
126 error if there is no 'F'. For INT modes, the names are
127 derived by prefixing a C to the name.
128
129 ADJUST_BYTESIZE (MODE, EXPR);
130 ADJUST_ALIGNMENT (MODE, EXPR);
131 ADJUST_FLOAT_FORMAT (MODE, EXPR);
132 Arrange for the byte size, alignment, or floating point format
133 of MODE to be adjustable at run time. EXPR will be executed
134 once after processing all command line options, and should
135 evaluate to the desired byte size, alignment, or format.
136
137 Unlike a FORMAT argument, if you are adjusting a float format
138 you must put an & in front of the name of each format structure.
139
140 Note: If a mode is ever made which is more than 255 bytes wide,
141 machmode.h and genmodes.c will have to be changed to allocate
142 more space for the mode_size and mode_alignment arrays. */
143
144/* VOIDmode is used when no mode needs to be specified,
145 as for example on CONST_INT RTL expressions. */
146RANDOM_MODE (VOID);
147
148/* BLKmode is used for structures, arrays, etc.
149 that fit no more specific mode. */
150RANDOM_MODE (BLK);
151
152/* Single bit mode used for booleans. */
153FRACTIONAL_INT_MODE (BI, 1, 1);
154
155/* Basic integer modes. We go up to TI in generic code (128 bits).
156 The name OI is reserved for a 256-bit type (needed by some back ends).
157 FIXME TI shouldn't be generically available either. */
158INT_MODE (QI, 1);
159INT_MODE (HI, 2);
160INT_MODE (SI, 4);
161INT_MODE (DI, 8);
162INT_MODE (TI, 16);
163
164/* No partial integer modes are defined by default. */
165
166/* Basic floating point modes. SF and DF are the only modes provided
167 by default. The names QF, HF, XF, and TF are reserved for targets
168 that need 1-word, 2-word, 80-bit, or 128-bit float types respectively.
169
170 These are the IEEE mappings. They can be overridden with
171 RESET_FLOAT_FORMAT or at runtime (in OVERRIDE_OPTIONS). */
172
173FLOAT_MODE (SF, 4, ieee_single_format);
174FLOAT_MODE (DF, 8, ieee_double_format);
175
176/* Basic CC modes.
177 FIXME define this only for targets that need it. */
178CC_MODE (CC);
179
180/* Allow the target to specify additional modes of various kinds. */
181#if HAVE_EXTRA_MODES
182# include EXTRA_MODES_FILE
183#endif
184
185/* Complex modes. */
186COMPLEX_MODES (INT);
187COMPLEX_MODES (FLOAT);
188
189/* Vector modes. */
190VECTOR_MODES (INT, 2); /* V2QI */
191VECTOR_MODES (INT, 4); /* V4QI V2HI */
192VECTOR_MODES (INT, 8); /* V8QI V4HI V2SI */
193VECTOR_MODES (INT, 16); /* V16QI V8HI V4SI V2DI */
194/* VECTOR_MODES (INT, 32); V8SI V4DI */
195/* VECTOR_MODES (INT, 64); V8DI */
196
197VECTOR_MODE (INT, SI, 8)
198VECTOR_MODE (INT, DI, 4);
199VECTOR_MODE (INT, DI, 8);
200
201/* PPC uses this to distinguish between DImode passed in
202 float registers and DImode passed in vector registers.
203 It would be in rs6000-modes.def but it's referenced in
204 c-common.c. FIXME. */
205
206VECTOR_MODE (INT, DI, 1);
207
208VECTOR_MODES (FLOAT, 4); /* V2HF */
209VECTOR_MODES (FLOAT, 8); /* V4HF V2SF */
210VECTOR_MODES (FLOAT, 16); /* V8HF V4SF V2DF */
211/* VECTOR_MODES (FLOAT, 32); V8SF V4DF */
212/* VECTOR_MODES (FLOAT, 64); V16SF V8DF */
213
214VECTOR_MODE (FLOAT, SF, 8);
215VECTOR_MODE (FLOAT, SF, 16);
216VECTOR_MODE (FLOAT, DF, 4);
217VECTOR_MODE (FLOAT, DF, 8);
218
219/* The symbol Pmode stands for one of the above machine modes (usually SImode).
220 The tm.h file specifies which one. It is not a distinct mode. */
221
222/*
223Local variables:
224mode:c
225version-control: t
226End:
227*/