qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Paolo Bonzini <pbonzini@redhat.com>
To: Richard Henderson <rth@twiddle.net>,
	Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>,
	Peter Maydell <peter.maydell@linaro.org>
Cc: Blue Swirl <blauwirbel@gmail.com>,
	QEMU Developers <qemu-devel@nongnu.org>
Subject: Re: [Qemu-devel] [PATCH] target-sparc: fix 32-bit truncation in fpackfix
Date: Thu, 5 Nov 2015 10:43:34 +0100	[thread overview]
Message-ID: <563B24C6.4020402@redhat.com> (raw)
In-Reply-To: <563B215A.5030205@twiddle.net>



On 05/11/2015 10:28, Richard Henderson wrote:
> On 11/05/2015 10:25 AM, Paolo Bonzini wrote:
>>
>>
>> On 05/11/2015 10:20, Richard Henderson wrote:
>>>
>>>>      /* Ugly code */
>>>>      int64_t scaled = (uint64_t)(int64_t)src << scale;
>>>
>>> You mean
>>>
>>>    int64_t scaled = (int64_t)((uint64_t)src << scale);
>>
>> No, that also looks like a typo.
>>
>> I mean:
>>
>> - unnecessary cast to int64_t to get the sign extension while avoiding
>> the impression of a typo
> 
> Huh.  This part doesn't seem a typo to me at all.

A cast _is_ obviously necessary, because src is int32_t and the result
is int64_t:

         int32_t src = rs2 >> (word * 32);
         int64_t scaled = (uint64_t)src << scale;

having uint64_t on the RHS and int64_t on the LHS definitely would be a
WTF cause for me.

Paolo

  reply	other threads:[~2015-11-05  9:43 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-02 14:05 [Qemu-devel] [PATCH] target-sparc: fix 32-bit truncation in fpackfix Paolo Bonzini
2015-11-02 14:09 ` Peter Maydell
2015-11-02 14:48   ` Paolo Bonzini
2015-11-02 15:13     ` Peter Maydell
2015-11-02 15:50       ` Paolo Bonzini
2015-11-04 10:12       ` Richard Henderson
2015-11-04 10:45         ` Paolo Bonzini
2015-11-04 11:05           ` Richard Henderson
2015-11-04 12:46             ` Paolo Bonzini
2015-11-04 14:07               ` Markus Armbruster
2015-11-04 16:06                 ` Paolo Bonzini
2015-11-04 17:53                   ` Markus Armbruster
2015-11-05  9:11                     ` Paolo Bonzini
2015-11-04 23:36             ` Mark Cave-Ayland
2015-11-05  9:12               ` Paolo Bonzini
2015-11-05  9:20                 ` Richard Henderson
2015-11-05  9:25                   ` Paolo Bonzini
2015-11-05  9:28                     ` Richard Henderson
2015-11-05  9:43                       ` Paolo Bonzini [this message]
2015-11-06 15:33                     ` Mark Cave-Ayland
2015-11-06 15:43                       ` Paolo Bonzini

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=563B24C6.4020402@redhat.com \
    --to=pbonzini@redhat.com \
    --cc=blauwirbel@gmail.com \
    --cc=mark.cave-ayland@ilande.co.uk \
    --cc=peter.maydell@linaro.org \
    --cc=qemu-devel@nongnu.org \
    --cc=rth@twiddle.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).