Date: Wed, 13 Mar 2019 16:41:51 +0100 From: Hans Petter Selasky <hps@selasky.org> To: sgk@troutmask.apl.washington.edu, freebsd-toolchain@freebsd.org, freebsd-current@freebsd.org Subject: Re: Optimization bug with floating-point? Message-ID: <14ead2c2-b586-309d-947f-1395b5284dd1@selasky.org> In-Reply-To: <20190313151635.GA34757@troutmask.apl.washington.edu> References: <20190313024506.GA31746@troutmask.apl.washington.edu> <20190313151635.GA34757@troutmask.apl.washington.edu>
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On 3/13/19 4:16 PM, Steve Kargl wrote:
> On Tue, Mar 12, 2019 at 07:45:41PM -0700, Steve Kargl wrote:
>>
>> gcc8 --version
>> gcc8 (FreeBSD Ports Collection) 8.3.0
>>
>> gcc8 -fno-builtin -o z a.c -lm && ./z
>> gcc8 -O -fno-builtin -o z a.c -lm && ./z
>> gcc8 -O2 -fno-builtin -o z a.c -lm && ./z
>> gcc8 -O3 -fno-builtin -o z a.c -lm && ./z
>>
>> Max ULP: 2.297073
>> Count: 0 (# of ULP that exceed 21)
>>
>
> clang agrees with gcc8 if one changes ...
>
>> int
>> main(void)
>> {
>> double re, im, u, ur, ui;
>> float complex f;
>> float x, y;
>
> this line to "volatile float x, y".
>
Can you try to use:
#define sincos(x,p,q) do { \
*(p) = sin(x); \
*(q) = cos(x); \
} while (0)
Instead of libm's sincos(). Might be a bug in there.
--HPS
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