| /* |
| ** 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 file |
| won't really be much use until double-precision is supported. |
| |
| However, once that is done, this file might eventually become a |
| replacement for libgcc1.c. It might also make possible |
| cross-compilation for an IEEE target machine from a non-IEEE |
| host 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); |