/* This file contains the definitions and documentation for the
machine modes used in the GNU compiler.
- Copyright (C) 1987, 1992, 1994, 1997, 1998, 2000, 2003
+ Copyright (C) 1987, 1992, 1994, 1997, 1998, 2000, 2003, 2004
Free Software Foundation, Inc.
This file is part of GCC.
A CLASS argument must be one of the constants defined in
mode-classes.def, less the leading MODE_ prefix; some statements
- that take CLASS arguments have restructions on which classes are
+ that take CLASS arguments have restrictions on which classes are
acceptable. For instance, INT.
A MODE argument must be the printable name of a machine mode,
without quotation marks or trailing "mode". For instance, SI.
- A BITSIZE, BYTESIZE, or COUNT argument must be a positive integer
+ A PRECISION, BYTESIZE, or COUNT argument must be a positive integer
constant.
+ A FORMAT argument must be one of the real_mode_format structures
+ declared in real.h, or else a literal 0. Do not put a leading &
+ on the argument.
+
+ An EXPR argument must be a syntactically valid C expression.
+ If an EXPR contains commas, you may need to write an extra pair of
+ parentheses around it, so it appears to be a single argument to the
+ statement.
+
+ This file defines only those modes which are of use on almost all
+ machines. Other modes can be defined in the target-specific
+ mode definition file, config/ARCH/ARCH-modes.def.
+
Order matters in this file in so far as statements which refer to
other modes must appear after the modes they refer to. However,
statements which do not refer to other modes may appear in any
declares MODE to be of class INT and BYTESIZE bytes wide.
All of the bits of its representation are significant.
- FRACTIONAL_INT_MODE (MODE, BITSIZE, BYTESIZE);
+ FRACTIONAL_INT_MODE (MODE, PRECISION, BYTESIZE);
declares MODE to be of class INT, BYTESIZE bytes wide in
- storage, but with only BITSIZE significant bits.
+ storage, but with only PRECISION significant bits.
- FLOAT_MODE (MODE, BYTESIZE);
- declares MODE to be of class FLOAT and BYTESIZE bytes wide.
+ FLOAT_MODE (MODE, BYTESIZE, FORMAT);
+ declares MODE to be of class FLOAT and BYTESIZE bytes wide,
+ using floating point format FORMAT.
All of the bits of its representation are significant.
- FRACTIONAL_FLOAT_MODE (MODE, BITSIZE, BYTESIZE);
+ FRACTIONAL_FLOAT_MODE (MODE, PRECISION, BYTESIZE, FORMAT);
declares MODE to be of class FLOAT, BYTESIZE bytes wide in
- storage, but with only BITSIZE significant bits.
+ storage, but with only PRECISION significant bits, using
+ floating point format FORMAT.
+
+ RESET_FLOAT_FORMAT (MODE, FORMAT);
+ changes the format of MODE, which must be class FLOAT,
+ to FORMAT. Use in an ARCH-modes.def to reset the format
+ of one of the float modes defined in this file.
PARTIAL_INT_MODE (MODE);
declares a mode of class PARTIAL_INT with the same size as
MODE (which must be an INT mode). The name of the new mode
is made by prefixing a P to the name MODE. This statement
- may grow a BITSIZE argument in the future.
+ may grow a PRECISION argument in the future.
VECTOR_MODE (CLASS, MODE, COUNT);
Declare a vector mode whose component mode is MODE (of class
error if there is no 'F'. For INT modes, the names are
derived by prefixing a C to the name.
- BITS_PER_UNIT (COUNT);
- Sets the number of bits in a machine byte (least addressable
- unit). If this statement does not appear, the default is 8.
+ ADJUST_BYTESIZE (MODE, EXPR);
+ ADJUST_ALIGNMENT (MODE, EXPR);
+ ADJUST_FLOAT_FORMAT (MODE, EXPR);
+ Arrange for the byte size, alignment, or floating point format
+ of MODE to be adjustable at run time. EXPR will be executed
+ once after processing all command line options, and should
+ evaluate to the desired byte size, alignment, or format.
+
+ Unlike a FORMAT argument, if you are adjusting a float format
+ you must put an & in front of the name of each format structure.
Note: If a mode is ever made which is more than 255 bytes wide,
machmode.h and genmodes.c will have to be changed to allocate
/* Single bit mode used for booleans. */
FRACTIONAL_INT_MODE (BI, 1, 1);
-/* Basic integer modes. */
+/* Basic integer modes. We go up to TI in generic code (128 bits).
+ The name OI is reserved for a 256-bit type (needed by some back ends).
+ FIXME TI shouldn't be generically available either. */
INT_MODE (QI, 1);
INT_MODE (HI, 2);
INT_MODE (SI, 4);
INT_MODE (DI, 8);
INT_MODE (TI, 16);
-INT_MODE (OI, 32);
-
-/* Pointers on some machines use these types to distinguish them from
- ints. Useful if a pointer is 4 bytes but has some bits that are
- not significant, so it is really not quite as wide as an integer. */
-PARTIAL_INT_MODE (QI);
-PARTIAL_INT_MODE (HI);
-PARTIAL_INT_MODE (SI);
-PARTIAL_INT_MODE (DI);
-
-/* Basic floating point modes. */
-FLOAT_MODE (QF, 1); /* C4x single precision */
-FLOAT_MODE (HF, 2); /* C4x double precision */
-FLOAT_MODE (TQF, 3); /* MIL-STD-1750a */
-FLOAT_MODE (SF, 4);
-FLOAT_MODE (DF, 8);
-FLOAT_MODE (XF, 12); /* IEEE extended (80-bit) */
-FLOAT_MODE (TF, 16);
-
-/* Basic CC modes. */
+
+/* No partial integer modes are defined by default. */
+
+/* Basic floating point modes. SF and DF are the only modes provided
+ by default. The names QF, HF, XF, and TF are reserved for targets
+ that need 1-word, 2-word, 80-bit, or 128-bit float types respectively.
+
+ These are the IEEE mappings. They can be overridden with
+ RESET_FLOAT_FORMAT or at runtime (in OVERRIDE_OPTIONS). */
+
+FLOAT_MODE (SF, 4, ieee_single_format);
+FLOAT_MODE (DF, 8, ieee_double_format);
+
+/* Basic CC modes.
+ FIXME define this only for targets that need it. */
CC_MODE (CC);
/* Allow the target to specify additional modes of various kinds. */
#if HAVE_EXTRA_MODES
-# define CC(X) CC_MODE(X); /* backward compatibility, temporary */
# include EXTRA_MODES_FILE
-# undef CC
#endif
/* Complex modes. */
COMPLEX_MODES (INT);
COMPLEX_MODES (FLOAT);
-/* Vector modes. */
-VECTOR_MODES (INT, 2); /* V2QI */
-VECTOR_MODES (INT, 4); /* V4QI V2HI */
-VECTOR_MODES (INT, 8); /* V8QI V4HI V2SI */
-VECTOR_MODES (INT, 16); /* V16QI V8HI V4SI V2DI */
-/* VECTOR_MODES (INT, 32); V8SI V4DI */
-/* VECTOR_MODES (INT, 64); V8DI */
-
-VECTOR_MODE (INT, SI, 8)
-VECTOR_MODE (INT, DI, 4);
-VECTOR_MODE (INT, DI, 8);
-
-VECTOR_MODE (INT, DI, 1); /* PPC uses this. Why not plain DI? */
-
-VECTOR_MODES (FLOAT, 4); /* V2HF */
-VECTOR_MODES (FLOAT, 8); /* V4HF V2SF */
-VECTOR_MODES (FLOAT, 16); /* V8HF V4SF V2DF */
-/* VECTOR_MODES (FLOAT, 32); V8SF V4DF */
-/* VECTOR_MODES (FLOAT, 64); V16SF V8DF */
-
-VECTOR_MODE (FLOAT, SF, 8);
-VECTOR_MODE (FLOAT, SF, 16);
-VECTOR_MODE (FLOAT, DF, 4);
-VECTOR_MODE (FLOAT, DF, 8);
-
/* The symbol Pmode stands for one of the above machine modes (usually SImode).
The tm.h file specifies which one. It is not a distinct mode. */
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