From 20dc758d24f3e6fc19c3d8a3a029a32072cd6a29 Mon Sep 17 00:00:00 2001 From: "Steven J. Magnani" Date: Wed, 10 Nov 2010 19:31:11 +0100 Subject: microblaze: Restore soft-float Software floating point for microblaze. Signed-off-by: Steven J. Magnani Signed-off-by: Bernhard Reutner-Fischer --- libc/sysdeps/linux/microblaze/fixdfsi.c | 85 +++++++++++++++++++++++++++++++++ 1 file changed, 85 insertions(+) create mode 100644 libc/sysdeps/linux/microblaze/fixdfsi.c (limited to 'libc/sysdeps/linux/microblaze/fixdfsi.c') diff --git a/libc/sysdeps/linux/microblaze/fixdfsi.c b/libc/sysdeps/linux/microblaze/fixdfsi.c new file mode 100644 index 000000000..1611176aa --- /dev/null +++ b/libc/sysdeps/linux/microblaze/fixdfsi.c @@ -0,0 +1,85 @@ +/* +** 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. +*/ + +#include "floatlib.h" + +/* convert double to int */ +long +__fixdfsi (double a1) +{ + register union double_long dl1; + register int exp; + register long l; + + dl1.d = a1; + + if (!dl1.l.upper && !dl1.l.lower) + return (0); + + exp = EXPD (dl1) - EXCESSD - 31; + l = MANTD (dl1); + + if (exp > 0) + return SIGND(dl1) ? (1<<31) : ((1ul<<31)-1); + + /* shift down until exp = 0 or l = 0 */ + if (exp < 0 && exp > -32 && l) + l >>= -exp; + else + return (0); + + return (SIGND (dl1) ? -l : l); +} -- cgit v1.2.3