Removed the optimized asm versions of scalb() and scalbf(). These

functions are only for compatibility with obsolete standards.  They
shouldn't be used, so they shouldn't be optimized.  Use the generic
versions instead.

This fixes scalbf() as a side effect.  The optimized asm version left
garbage on the FP stack.  I fixed the corresponding bug in the optimized
asm scalb() and scalbn() in 1996.  NetBSD fixed it in scalb(), scalbn()
and scalbnf() in 1999 but missed fixing it in scalbf().  Then in 2005
the bug was reimplemented in FreeBSD by importing NetBSD's scalbf().

The generic versions have slightly different error handling:
- the asm versions blindly round the second parameter to a (floating
  point) integer and proceed, while the generic versions return NaN
  if this rounding changes the value.  POSIX permits both behaviours
  (these functions are XSI extensions and the behaviour for a bogus
  non-integral second parameter is unspecified).   Apart from this
  and the bug in scalbf(), the behaviour of the generic versions seems
  to be identical.  (I only exhusatively tested
  generic_scalbf(1.0F, anyfloat) == asm_scalb(1.0F, anyfloat).  This
  covers many representative corner cases involving NaNs and Infs but
  doesn't test exception flags.  The brokenness of scalbf() showed up
  as weird behaviour after testing just 7 integer cases sequentially.)
This commit is contained in:
Bruce Evans 2006-07-05 20:06:42 +00:00
parent 761aed363f
commit 3454a5a101
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=160118
3 changed files with 2 additions and 62 deletions

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@ -1,13 +1,13 @@
# $FreeBSD$
ARCH_SRCS = e_exp.S e_fmod.S e_log.S e_log10.S \
e_remainder.S e_scalb.S e_sqrt.S s_ceil.S s_copysign.S \
e_remainder.S e_sqrt.S s_ceil.S s_copysign.S \
s_cos.S s_finite.S s_floor.S s_llrint.S s_logb.S s_lrint.S \
s_remquo.S s_rint.S s_scalbn.S s_significand.S s_sin.S s_tan.S \
s_trunc.S
# float counterparts
ARCH_SRCS+= e_log10f.S e_logf.S e_remainderf.S e_scalbf.S \
ARCH_SRCS+= e_log10f.S e_logf.S e_remainderf.S \
e_sqrtf.S s_ceilf.S s_copysignf.S s_floorf.S \
s_llrintf.S s_logbf.S s_lrintf.S \
s_remquof.S s_rintf.S s_scalbnf.S s_significandf.S s_truncf.S

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@ -1,45 +0,0 @@
/*
* Copyright (c) 1994 Winning Strategies, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Winning Strategies, Inc.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Written by:
* J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc.
*/
#include <machine/asm.h>
RCSID("$FreeBSD$")
ENTRY(scalb)
fldl 12(%esp)
fldl 4(%esp)
fscale
fstp %st(1)
ret

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@ -1,15 +0,0 @@
/*
* Written by J.T. Conklin <jtc@netbsd.org>.
* Public domain.
*/
#include <machine/asm.h>
__FBSDID("$FreeBSD$");
/* RCSID("$NetBSD: e_scalbf.S,v 1.1 1996/07/03 16:50:24 jtc Exp $") */
ENTRY(scalbf)
flds 8(%esp)
flds 4(%esp)
fscale
ret