From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753384AbdKQLGo (ORCPT ); Fri, 17 Nov 2017 06:06:44 -0500 Received: from mx2.suse.de ([195.135.220.15]:59222 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752715AbdKQLGi (ORCPT ); Fri, 17 Nov 2017 06:06:38 -0500 Date: Fri, 17 Nov 2017 12:06:36 +0100 Message-ID: From: Takashi Iwai To: "Colin King" Cc: , "Jaroslav Kysela" , , Subject: Re: [PATCH] ALSA: synth: emux: remove redundant test for r <= 13 In-Reply-To: <20171114172653.6690-1-colin.king@canonical.com> References: <20171114172653.6690-1-colin.king@canonical.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/25.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 14 Nov 2017 18:26:53 +0100, Colin King wrote: > > From: Colin Ian King > > The calculation r = (3 - ((rate >> 6) & 3)) * 3 results in r being > 0, 3, 6 or 9 and so the check (13 > r) is always true and hence we > can remove the redundant check and the else path. > > Detected by CoverityScan, CID#744415 ("Logically dead code") > > Signed-off-by: Colin Ian King The calculation of t itself can be generic in case we may add a support greater than the current r, so I don't think it's so much beneficial with this code reduction. Better to keep the code as reference. thanks, Takashi > --- > sound/synth/emux/soundfont.c | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) > > diff --git a/sound/synth/emux/soundfont.c b/sound/synth/emux/soundfont.c > index 31a4ea94830e..0beb5a737c8b 100644 > --- a/sound/synth/emux/soundfont.c > +++ b/sound/synth/emux/soundfont.c > @@ -858,10 +858,7 @@ calc_gus_envelope_time(int rate, int start, int end) > p = rate & 0x3f; > t = end - start; > if (t < 0) t = -t; > - if (13 > r) > - t = t << (13 - r); > - else > - t = t >> (r - 13); > + t = t << (13 - r); > return (t * 10) / (p * 441); > } > > -- > 2.14.1 > >