From: Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>
To: "H.J. Lu" <hjl.tools@gmail.com>, Fangrui Song <maskray@google.com>
Cc: GNU C Library <libc-alpha@sourceware.org>
Subject: Re: [PATCH] i386: Use fldt instead of fld on e_logl.S
Date: Fri, 5 Aug 2022 09:28:18 -0300 [thread overview]
Message-ID: <bb8b9156-dc2e-a7ff-58b2-813d75eb5084@linaro.org> (raw)
In-Reply-To: <CAMe9rOprc_oTVB_cyA=-FBrjW5o0GBtr2rhUbki=VLwVd+M8Eg@mail.gmail.com>
On 04/08/22 18:35, H.J. Lu wrote:
> On Thu, Aug 4, 2022 at 2:31 PM Fangrui Song <maskray@google.com> wrote:
>>
>> On Thu, Aug 4, 2022 at 2:24 PM H.J. Lu <hjl.tools@gmail.com> wrote:
>>>
>>> On Thu, Aug 4, 2022 at 2:00 PM Adhemerval Zanella
>>> <adhemerval.zanella@linaro.org> wrote:
>>>>
>>>> Clang cannot assemble fldt in the AT&T dialect mode.
>>>> ---
>>>> sysdeps/i386/i686/fpu/e_logl.S | 4 ++--
>>>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/sysdeps/i386/i686/fpu/e_logl.S b/sysdeps/i386/i686/fpu/e_logl.S
>>>> index 63183ac544..5d53f3bb22 100644
>>>> --- a/sysdeps/i386/i686/fpu/e_logl.S
>>>> +++ b/sysdeps/i386/i686/fpu/e_logl.S
>>>> @@ -43,7 +43,7 @@ ENTRY(__ieee754_logl)
>>>> fsubl MO(one) // x-1 : x : log(2)
>>>> 5: fld %st // x-1 : x-1 : x : log(2)
>>>> fabs // |x-1| : x-1 : x : log(2)
>>>> - fld MO(limit) // 0.29 : |x-1| : x-1 : x : log(2)
>>>> + fldt MO(limit) // 0.29 : |x-1| : x-1 : x : log(2)
>>>> fcomip %st(1) // |x-1| : x-1 : x : log(2)
>>>> fstp %st(0) // x-1 : x : log(2)
>>>> jc 2f
>>>> @@ -76,7 +76,7 @@ ENTRY(__logl_finite)
>>>> fsubl MO(one) // x-1 : x : log(2)
>>>> fld %st // x-1 : x-1 : x : log(2)
>>>> fabs // |x-1| : x-1 : x : log(2)
>>>> - fld MO(limit) // 0.29 : |x-1| : x-1 : x : log(2)
>>>> + fldt MO(limit) // 0.29 : |x-1| : x-1 : x : log(2)
>>>> fcomip %st(1) // |x-1| : x-1 : x : log(2)
>>>> fstp %st(0) // x-1 : x : log(2)
>>>> jc 2b
>>>> --
>>>> 2.34.1
>>>>
>>>
>>> I don't think this is correct since there are
>>>
>>> .type limit,@object
>>> limit: .double 0.29
>>>
>>> It should be fldl.
>>>
>>> --
>>> H.J.
>>
>> If I am not mistaken, the existing fld has a bug as it is treated as flds
>
> True. It doesn't seem to cause any issue.
>
>> fld limit@GOTOFF(%edx) # treated as flds
>> flds limit@GOTOFF(%edx)
>> fldl limit@GOTOFF(%edx)
>> fldt limit@GOTOFF(%edx)
>>
>> .section .rodata.cst8,"aM",@progbits,8
>> .p2align 3
>> limit: .double 0.29
fldl works and it see the best option. Ok with this change?
next prev parent reply other threads:[~2022-08-05 12:28 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-04 21:00 Adhemerval Zanella
2022-08-04 21:23 ` H.J. Lu
2022-08-04 21:31 ` Fangrui Song
2022-08-04 21:35 ` H.J. Lu
2022-08-05 12:28 ` Adhemerval Zanella Netto [this message]
2022-08-05 16:55 ` H.J. Lu
2022-08-05 17:23 ` Andreas Schwab
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