/* ** 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);