diff options
Diffstat (limited to 'contrib/gdtoa/gdtoaimp.h')
| -rw-r--r-- | contrib/gdtoa/gdtoaimp.h | 47 |
1 files changed, 23 insertions, 24 deletions
diff --git a/contrib/gdtoa/gdtoaimp.h b/contrib/gdtoa/gdtoaimp.h index 9991ffa..75cdc4e 100644 --- a/contrib/gdtoa/gdtoaimp.h +++ b/contrib/gdtoa/gdtoaimp.h @@ -96,7 +96,12 @@ THIS SOFTWARE. * #define RND_PRODQUOT to use rnd_prod and rnd_quot (assembly routines * that use extended-precision instructions to compute rounded * products and quotients) with IBM. - * #define ROUND_BIASED for IEEE-format with biased rounding. + * #define ROUND_BIASED for IEEE-format with biased rounding and arithmetic + * that rounds toward +Infinity. + * #define ROUND_BIASED_without_Round_Up for IEEE-format with biased + * rounding when the underlying floating-point arithmetic uses + * unbiased rounding. This prevent using ordinary floating-point + * arithmetic when the result could be computed with one rounding error. * #define Inaccurate_Divide for IEEE-format with correctly rounded * products but inaccurate quotients, e.g., for Intel i860. * #define NO_LONG_LONG on machines that do not have a "long long" @@ -115,7 +120,12 @@ THIS SOFTWARE. * #define MALLOC your_malloc, where your_malloc(n) acts like malloc(n) * if memory is available and otherwise does something you deem * appropriate. If MALLOC is undefined, malloc will be invoked - * directly -- and assumed always to succeed. + * directly -- and assumed always to succeed. Similarly, if you + * want something other than the system's free() to be called to + * recycle memory acquired from MALLOC, #define FREE to be the + * name of the alternate routine. (FREE or free is only called in + * pathological cases, e.g., in a gdtoa call after a gdtoa return in + * mode 3 with thousands of digits requested.) * #define Omit_Private_Memory to omit logic (added Jan. 1998) for making * memory allocations from a private pool of memory when possible. * When used, the private pool is PRIVATE_MEM bytes long: 2304 bytes, @@ -164,11 +174,6 @@ THIS SOFTWARE. * #define NO_STRING_H to use private versions of memcpy. * On some K&R systems, it may also be necessary to * #define DECLARE_SIZE_T in this case. - * #define YES_ALIAS to permit aliasing certain double values with - * arrays of ULongs. This leads to slightly better code with - * some compilers and was always used prior to 19990916, but it - * is not strictly legal and can cause trouble with aggressively - * optimizing compilers (e.g., gcc 2.95.1 under -O2). * #define USE_LOCALE to use the current locale's decimal_point value. */ @@ -287,25 +292,14 @@ Exactly one of IEEE_8087, IEEE_MC68k, VAX, or IBM should be defined. typedef union { double d; ULong L[2]; } U; -#ifdef YES_ALIAS -#define dval(x) x #ifdef IEEE_8087 -#define word0(x) ((ULong *)&x)[1] -#define word1(x) ((ULong *)&x)[0] +#define word0(x) (x)->L[1] +#define word1(x) (x)->L[0] #else -#define word0(x) ((ULong *)&x)[0] -#define word1(x) ((ULong *)&x)[1] +#define word0(x) (x)->L[0] +#define word1(x) (x)->L[1] #endif -#else /* !YES_ALIAS */ -#ifdef IEEE_8087 -#define word0(x) ((U*)&x)->L[1] -#define word1(x) ((U*)&x)->L[0] -#else -#define word0(x) ((U*)&x)->L[0] -#define word1(x) ((U*)&x)->L[1] -#endif -#define dval(x) ((U*)&x)->d -#endif /* YES_ALIAS */ +#define dval(x) (x)->d /* The following definition of Storeinc is appropriate for MIPS processors. * An alternative that might be better on some machines is @@ -419,6 +413,11 @@ typedef union { double d; ULong L[2]; } U; #ifndef IEEE_Arith #define ROUND_BIASED +#else +#ifdef ROUND_BIASED_without_Round_Up +#undef ROUND_BIASED +#define ROUND_BIASED +#endif #endif #ifdef RND_PRODQUOT @@ -659,7 +658,7 @@ extern void memcpy_D2A ANSI((void*, const void*, size_t)); extern int strtorxL ANSI((CONST char *, char **, int, void *)); extern Bigint *sum ANSI((Bigint*, Bigint*)); extern int trailz ANSI((Bigint*)); - extern double ulp ANSI((double)); + extern double ulp ANSI((U*)); #ifdef __cplusplus } |
