Date: Mon, 4 Mar 2019 13:21:59 -0800 From: Steve Kargl <sgk@troutmask.apl.washington.edu> To: Bruce Evans <brde@optusnet.com.au> Cc: freebsd-numerics@freebsd.org Subject: Re: Update ENTERI() macro Message-ID: <20190304212159.GA12587@troutmask.apl.washington.edu> In-Reply-To: <20190228060920.R4413@besplex.bde.org> References: <20190226191825.GA68479@troutmask.apl.washington.edu> <20190227145002.P907@besplex.bde.org> <20190227074811.GA75972@troutmask.apl.washington.edu> <20190227201214.V1823@besplex.bde.org> <20190227161906.GA77785@troutmask.apl.washington.edu> <20190228060920.R4413@besplex.bde.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, Feb 28, 2019 at 07:15:14AM +1100, Bruce Evans wrote:
> On Wed, 27 Feb 2019, Steve Kargl wrote:
>
> > On Wed, Feb 27, 2019 at 09:15:52PM +1100, Bruce Evans wrote:
> >>
> >> ENTERI() hard-codes the long double for simplicity. Remember, it is only
> >> needed for long double precision on i386. But I forgot about long double
> >> complex types, and didn't dream about indirect long double types in sincosl().
> >
> > That simplicity does not work for long double complex. We will
> >
> > need either ENTERIC as in
> >
> > #define ENTERIC() ENTERIT(long double complex)
> >
> > or a direct use of ENTERIT as you have done s_clogl.c
>
> I wrote ENTERIT() to work around this problem.
>
> >>> I'm fine with making ENTERI() only toggle precision, and adding
> >>> a LEAVEI() to reset precision. RETURNI(r) would then be
> >>>
> >>> #define RETURNI(r) \
> >>> do { \
> >>> LEAVEI(); \
> >>> return (r); \
> >>> } while (0)
> >>
> >> No, may be an expression, so it must be evaluated before LEAVEI(). This
> >> is the reason for existence of the variable to hold the result.
> >
> > So, we'll need RETURNI for long double and one for long double complex.
> > Or, we give RETURNI a second parameter, which is the input parameter of
> > the function
>
> I said to use your method of __typeof(). I tested this:
>
> XX --- /tmp/math_private.h Sun Nov 27 17:58:57 2005
> XX +++ ./math_private.h Thu Feb 28 06:17:26 2019
> XX @@ -474,21 +474,22 @@
> XX /* Support switching the mode to FP_PE if necessary. */
> XX #if defined(__i386__) && !defined(NO_FPSETPREC)
> XX -#define ENTERI() ENTERIT(long double)
> XX -#define ENTERIT(returntype) \
> XX - returntype __retval; \
> XX +#define ENTERI() \
> XX fp_prec_t __oprec; \
> XX \
> XX if ((__oprec = fpgetprec()) != FP_PE) \
> XX fpsetprec(FP_PE)
> XX -#define RETURNI(x) do { \
> XX - __retval = (x); \
> XX - if (__oprec != FP_PE) \
> XX - fpsetprec(__oprec); \
> XX +#define LEAVEI() \
> XX + if ((__oprec = fpgetprec()) != FP_PE) \
> XX + fpsetprec(FP_PE)
Am I reading this diff wrong? Should LEAVEI() be
#define LEAVEI() \
if (__oprec != FP_PE) \
fpsetprec(__oprec)
That is, we want to reset the precision to what ENTERI
grabbed in its conditinal expression.
--
Steve
20170425 https://www.youtube.com/watch?v=VWUpyCsUKR4
20161221 https://www.youtube.com/watch?v=IbCHE-hONow
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20190304212159.GA12587>