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- /*
- ** 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);
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