| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140 | /*** libgcc support for software floating point.** Copyright (C) 1991 by Pipeline Associates, Inc.  All rights reserved.** Permission is granted to do *anything* you want with this file,** commercial or otherwise, provided this message remains intact.  So there!** I would appreciate receiving any updates/patches/changes that anyone** makes, and am willing to be the repository for said changes (am I** making a big mistake?).Warning! Only single-precision is actually implemented.  This filewon't really be much use until double-precision is supported.However, once that is done, this file might eventually become areplacement for libgcc1.c.  It might also make possiblecross-compilation for an IEEE target machine from a non-IEEEhost such as a VAX.If you'd like to work on completing this, please talk to rms@gnu.ai.mit.edu.--> Double precision floating support added by James Carlson on 20 April 1998.**** Pat Wood** Pipeline Associates, Inc.** pipeline!phw@motown.com or** sun!pipeline!phw or** uunet!motown!pipeline!phw**** 05/01/91 -- V1.0 -- first release to gcc mailing lists** 05/04/91 -- V1.1 -- added float and double prototypes and return values**                  -- fixed problems with adding and subtracting zero**                  -- fixed rounding in truncdfsf2**                  -- fixed SWAP define and tested on 386*//*** The following are routines that replace the libgcc soft floating point** routines that are called automatically when -msoft-float is selected.** The support single and double precision IEEE format, with provisions** for byte-swapped machines (tested on 386).  Some of the double-precision** routines work at full precision, but most of the hard ones simply punt** and call the single precision routines, producing a loss of accuracy.** long long support is not assumed or included.** Overall accuracy is close to IEEE (actually 68882) for single-precision** arithmetic.  I think there may still be a 1 in 1000 chance of a bit** being rounded the wrong way during a multiply.  I'm not fussy enough to** bother with it, but if anyone is, knock yourself out.**** Efficiency has only been addressed where it was obvious that something** would make a big difference.  Anyone who wants to do this right for** best speed should go in and rewrite in assembler.**** I have tested this only on a 68030 workstation and 386/ix integrated** in with -msoft-float.*/#ifndef __FLOAT_LIB_H__#define __FLOAT_LIB_H__/* the following deal with IEEE single-precision numbers */#define EXCESS		126#define SIGNBIT		0x80000000#define HIDDEN		(1 << 23)#define SIGN(fp)	((fp) & SIGNBIT)#define EXP(fp)		(((fp) >> 23) & 0xFF)#define MANT(fp)	(((fp) & 0x7FFFFF) | HIDDEN)#define PACK(s,e,m)	((s) | ((e) << 23) | (m))/* the following deal with IEEE double-precision numbers */#define EXCESSD		1022#define HIDDEND		(1 << 20)#define EXPD(fp)	(((fp.l.upper) >> 20) & 0x7FF)#define SIGND(fp)	((fp.l.upper) & SIGNBIT)#define MANTD(fp)	(((((fp.l.upper) & 0xFFFFF) | HIDDEND) << 10) | \				(fp.l.lower >> 22))#define HIDDEND_LL	((long long)1 << 52)#define MANTD_LL(fp)	((fp.ll & (HIDDEND_LL-1)) | HIDDEND_LL)#define PACKD_LL(s,e,m)	(((long long)((s)+((e)<<20))<<32)|(m))/* define SWAP for 386/960 reverse-byte-order brain-damaged CPUs */union double_long {    double d;#ifdef SWAP    struct {      unsigned long lower;      long upper;    } l;#else    struct {      long upper;      unsigned long lower;    } l;#endif    long long ll;};union float_long  {    float f;    long l;  };#endif/* Functions defined in different files */float __addsf3 (float, float);float __subsf3 (float, float);long __cmpsf2 (float, float);float __mulsf3 (float, float);float __divsf3 (float, float);double __floatsidf (register long);double __floatdidf (register long long);float __floatsisf (register long );float __floatdisf (register long long );float __negsf2 (float);double __negdf2 (double);double __extendsfdf2 (float);float __truncdfsf2 (double);long __cmpdf2 (double, double);long __fixsfsi (float);long __fixdfsi (double);long long __fixdfdi (double);unsigned long __fixunsdfsi (double);unsigned long long __fixunsdfdi (double);double __adddf3 (double, double);double __subdf3 (double, double);double __muldf3 (double, double);double __divdf3 (double, double);int __gtdf2 (double, double);int __gedf2 (double, double);int __ltdf2 (double, double);int __ledf2 (double, double);int __eqdf2 (double, double);int __nedf2 (double, double);int __gtsf2 (float, float);int __gesf2 (float, float);int __ltsf2 (float, float);int __lesf2 (float, float);int __eqsf2 (float, float);int __nesf2 (float, float);
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