real.h

GCC编译器源代码

typedef struct {
    HOST_WIDE_INT r[sizeof (double)/sizeof (HOST_WIDE_INT)];
  } realvaluetype;
#define REAL_VALUE_TYPE realvaluetype
#endif /* no REAL_VALUE_TYPE */
#endif /* formats differ */
#endif /* 0 */

#endif /* emulator not used */

/* If we are not cross-compiling, use a `double' to represent the
   floating-point value.  Otherwise, use some other type
   (probably a struct containing an array of longs).  */
#ifndef REAL_VALUE_TYPE
#define REAL_VALUE_TYPE double
#else
#define REAL_IS_NOT_DOUBLE
#endif

#if HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT

/* Convert a type `double' value in host format first to a type `float'
   value in host format and then to a single type `long' value which
   is the bitwise equivalent of the `float' value.  */
#ifndef REAL_VALUE_TO_TARGET_SINGLE
#define REAL_VALUE_TO_TARGET_SINGLE(IN, OUT)				\
do { float f = (float) (IN);						\
     (OUT) = *(long *) &f;						\
   } while (0)
#endif

/* Convert a type `double' value in host format to a pair of type `long'
   values which is its bitwise equivalent, but put the two words into
   proper word order for the target.  */
#ifndef REAL_VALUE_TO_TARGET_DOUBLE
#define REAL_VALUE_TO_TARGET_DOUBLE(IN, OUT)				\
do { REAL_VALUE_TYPE in = (IN);  /* Make sure it's not in a register.  */\
     if (HOST_FLOAT_WORDS_BIG_ENDIAN == FLOAT_WORDS_BIG_ENDIAN)		\
       {								\
	 (OUT)[0] = ((long *) &in)[0];					\
	 (OUT)[1] = ((long *) &in)[1];					\
       }								\
     else								\
       {								\
	 (OUT)[1] = ((long *) &in)[0];					\
	 (OUT)[0] = ((long *) &in)[1];					\
       }								\
   } while (0)
#endif
#endif /* HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT */

/* In this configuration, double and long double are the same. */
#ifndef REAL_VALUE_TO_TARGET_LONG_DOUBLE
#define REAL_VALUE_TO_TARGET_LONG_DOUBLE(a, b) REAL_VALUE_TO_TARGET_DOUBLE (a, b)
#endif

/* Compare two floating-point objects for bitwise identity.
   This is not the same as comparing for equality on IEEE hosts:
   -0.0 equals 0.0 but they are not identical, and conversely
   two NaNs might be identical but they cannot be equal.  */
#define REAL_VALUES_IDENTICAL(x, y) \
  (!bcmp ((char *) &(x), (char *) &(y), sizeof (REAL_VALUE_TYPE)))

/* Compare two floating-point values for equality.  */
#ifndef REAL_VALUES_EQUAL
#define REAL_VALUES_EQUAL(x, y) ((x) == (y))
#endif

/* Compare two floating-point values for less than.  */
#ifndef REAL_VALUES_LESS
#define REAL_VALUES_LESS(x, y) ((x) < (y))
#endif

/* Truncate toward zero to an integer floating-point value.  */
#ifndef REAL_VALUE_RNDZINT
#define REAL_VALUE_RNDZINT(x) ((double) ((int) (x)))
#endif

/* Truncate toward zero to an unsigned integer floating-point value.  */
#ifndef REAL_VALUE_UNSIGNED_RNDZINT
#define REAL_VALUE_UNSIGNED_RNDZINT(x) ((double) ((unsigned int) (x)))
#endif

/* Convert a floating-point value to integer, rounding toward zero.  */
#ifndef REAL_VALUE_FIX
#define REAL_VALUE_FIX(x) ((int) (x))
#endif

/* Convert a floating-point value to unsigned integer, rounding
   toward zero. */
#ifndef REAL_VALUE_UNSIGNED_FIX
#define REAL_VALUE_UNSIGNED_FIX(x) ((unsigned int) (x))
#endif

/* Scale X by Y powers of 2.  */
#ifndef REAL_VALUE_LDEXP
#define REAL_VALUE_LDEXP(x, y) ldexp (x, y)
extern double ldexp ();
#endif

/* Convert the string X to a floating-point value.  */
#ifndef REAL_VALUE_ATOF
#if 1
/* Use real.c to convert decimal numbers to binary, ... */
REAL_VALUE_TYPE ereal_atof ();
#define REAL_VALUE_ATOF(x, s) ereal_atof (x, s)
#else
/* ... or, if you like the host computer's atof, go ahead and use it: */
#define REAL_VALUE_ATOF(x, s) atof (x)
#if defined (MIPSEL) || defined (MIPSEB)
/* MIPS compiler can't handle parens around the function name.
   This problem *does not* appear to be connected with any
   macro definition for atof.  It does not seem there is one.  */
extern double atof ();
#else
extern double (atof) ();
#endif
#endif
#endif

/* Negate the floating-point value X.  */
#ifndef REAL_VALUE_NEGATE
#define REAL_VALUE_NEGATE(x) (- (x))
#endif

/* Truncate the floating-point value X to mode MODE.  This is correct only
   for the most common case where the host and target have objects of the same
   size and where `float' is SFmode.  */

/* Don't use REAL_VALUE_TRUNCATE directly--always call real_value_truncate.  */
extern REAL_VALUE_TYPE real_value_truncate PROTO((enum machine_mode, REAL_VALUE_TYPE));

#ifndef REAL_VALUE_TRUNCATE
#define REAL_VALUE_TRUNCATE(mode, x) \
 (GET_MODE_BITSIZE (mode) == sizeof (float) * HOST_BITS_PER_CHAR	\
  ? (float) (x) : (x))
#endif

/* Determine whether a floating-point value X is infinite. */
#ifndef REAL_VALUE_ISINF
#define REAL_VALUE_ISINF(x) (target_isinf (x))
#endif

/* Determine whether a floating-point value X is a NaN. */
#ifndef REAL_VALUE_ISNAN
#define REAL_VALUE_ISNAN(x) (target_isnan (x))
#endif

/* Determine whether a floating-point value X is negative. */
#ifndef REAL_VALUE_NEGATIVE
#define REAL_VALUE_NEGATIVE(x) (target_negative (x))
#endif

extern int target_isnan			PROTO ((REAL_VALUE_TYPE));
extern int target_isinf			PROTO ((REAL_VALUE_TYPE));
extern int target_negative		PROTO ((REAL_VALUE_TYPE));

/* Determine whether a floating-point value X is minus 0. */
#ifndef REAL_VALUE_MINUS_ZERO
#define REAL_VALUE_MINUS_ZERO(x) ((x) == 0 && REAL_VALUE_NEGATIVE (x))
#endif

/* Constant real values 0, 1, 2, and -1.  */

extern REAL_VALUE_TYPE dconst0;
extern REAL_VALUE_TYPE dconst1;
extern REAL_VALUE_TYPE dconst2;
extern REAL_VALUE_TYPE dconstm1;

/* Union type used for extracting real values from CONST_DOUBLEs
   or putting them in.  */

union real_extract 
{
  REAL_VALUE_TYPE d;
  HOST_WIDE_INT i[sizeof (REAL_VALUE_TYPE) / sizeof (HOST_WIDE_INT)];
};

/* For a CONST_DOUBLE:
   The usual two ints that hold the value.
   For a DImode, that is all there are;
    and CONST_DOUBLE_LOW is the low-order word and ..._HIGH the high-order.
   For a float, the number of ints varies,
    and CONST_DOUBLE_LOW is the one that should come first *in memory*.
    So use &CONST_DOUBLE_LOW(r) as the address of an array of ints.  */
#define CONST_DOUBLE_LOW(r) XWINT (r, 2)
#define CONST_DOUBLE_HIGH(r) XWINT (r, 3)

/* Link for chain of all CONST_DOUBLEs in use in current function.  */
#define CONST_DOUBLE_CHAIN(r) XEXP (r, 1)
/* The MEM which represents this CONST_DOUBLE's value in memory,
   or const0_rtx if no MEM has been made for it yet,
   or cc0_rtx if it is not on the chain.  */
#define CONST_DOUBLE_MEM(r) XEXP (r, 0)

/* Function to return a real value (not a tree node)
   from a given integer constant.  */
REAL_VALUE_TYPE real_value_from_int_cst ();

/* Given a CONST_DOUBLE in FROM, store into TO the value it represents.  */

#define REAL_VALUE_FROM_CONST_DOUBLE(to, from)		\
do { union real_extract u;				\
     bcopy ((char *) &CONST_DOUBLE_LOW ((from)), (char *) &u, sizeof u); \
     to = u.d; } while (0)

/* Return a CONST_DOUBLE with value R and mode M.  */

#define CONST_DOUBLE_FROM_REAL_VALUE(r, m) immed_real_const_1 (r,  m)
extern struct rtx_def *immed_real_const_1	PROTO((REAL_VALUE_TYPE,
						       enum machine_mode));


/* Convert a floating point value `r', that can be interpreted
   as a host machine float or double, to a decimal ASCII string `s'
   using printf format string `fmt'.  */
#ifndef REAL_VALUE_TO_DECIMAL
#define REAL_VALUE_TO_DECIMAL(r, fmt, s) (sprintf (s, fmt, r))
#endif

/* Replace R by 1/R in the given machine mode, if the result is exact.  */
extern int exact_real_inverse PROTO((enum machine_mode, REAL_VALUE_TYPE *));

extern void debug_real			PROTO ((REAL_VALUE_TYPE));

/* In varasm.c */
extern void assemble_real		PROTO ((REAL_VALUE_TYPE,
						enum machine_mode));
#endif /* Not REAL_H_INCLUDED */