From patchwork Sat Aug 1 13:46:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andreas Rheinhardt X-Patchwork-Id: 21429 Return-Path: X-Original-To: patchwork@ffaux-bg.ffmpeg.org Delivered-To: patchwork@ffaux-bg.ffmpeg.org Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by ffaux.localdomain (Postfix) with ESMTP id CAD9B44AA8D for ; Sat, 1 Aug 2020 16:49:39 +0300 (EEST) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id B4FAA68BA7C; Sat, 1 Aug 2020 16:49:39 +0300 (EEST) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from mail-ed1-f65.google.com (mail-ed1-f65.google.com [209.85.208.65]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id E99C968BA56 for ; Sat, 1 Aug 2020 16:49:32 +0300 (EEST) Received: by mail-ed1-f65.google.com with SMTP id bs17so5461597edb.1 for ; Sat, 01 Aug 2020 06:49:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=93cN6ncx64Ir0bWhNfPydK+xFidjiQQQCYy6z7ZOAeI=; b=B5a017h7YVVIhLZ2Nj1VOGTjJ1mpLDhDsxauA9YKLPMv/Im8XuuikK66VPkLPx2fUW SfJCvtFY41W4sB+QW3PZITEGQL6SPhLY0PJX1AEDHGCcozHGCTxz7LLQLp++aS58dUj6 wfr8HmhQd3Pe1HdsozWv7g710LwiiXuGxyIjrhZRZHa85guTdZGLMy/oWAL5ye+Psahy keREsQwdVL4eIyH1Cw3h8HzSq6mLYqQKd3PXoCJ/Jkqn+vuVyPHbR/M05Nl5xGCQ650/ R2eyGadYknSVkn201pfnmYSyVUQsbOrq91s3o5GwjcEQOsaITKRz3NFimy42PwkUG09R u0Iw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=93cN6ncx64Ir0bWhNfPydK+xFidjiQQQCYy6z7ZOAeI=; b=AoTTCIJEodjUHS0BHqIUBwpW7bRD6iG14JOdZmOFx7oufmsdKjgXZxWcTn1mL0KMYC sBukEBGTBnAiw0flAE+Cl+22dZY6PYaqJGGfaAA3qyLYXfIw7xLIEPxY1/8c1jNuEnkc YI4Q3stlV/KPvnNTtF815vE5aFn+H8WVETayxxRf22fV65KCU3sj5nMZXp2gtHwRWhMP srVf4InQL5XM3dIStv+whUDQgQhrtsmkW+k6Gi4cnOSgyCIPR6TpYnRvQ4pY9c7SQXsb R0075dmppO4AVJCPOD5TS8+ragCKgsYeDqC5vip0KR97dbMY/ECxyVKt0ZwAt7okyH8L Nblg== X-Gm-Message-State: AOAM530gd9wmPuH50nE61+JSjHvBZNLHmGqEJuoqzbnnxaK5RiglZarV WqvxCoNAN8WsQFXSF+J5vwCXhGMc X-Google-Smtp-Source: ABdhPJzLZ5+qumWhCmIG/px+M6F9RWTYGQgrlIy6zbeT87qLu9XFTHmf/ebQqovK5BKji4JzNUlWGw== X-Received: by 2002:a50:fc02:: with SMTP id i2mr8455405edr.121.1596289772068; Sat, 01 Aug 2020 06:49:32 -0700 (PDT) Received: from sblaptop.fritz.box (ipbcc10296.dynamic.kabel-deutschland.de. [188.193.2.150]) by smtp.gmail.com with ESMTPSA id b24sm12178501edn.33.2020.08.01.06.49.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 01 Aug 2020 06:49:31 -0700 (PDT) From: Andreas Rheinhardt To: ffmpeg-devel@ffmpeg.org Date: Sat, 1 Aug 2020 15:46:55 +0200 Message-Id: <20200801134704.3647-4-andreas.rheinhardt@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200731112241.8948-1-andreas.rheinhardt@gmail.com> References: <20200731112241.8948-1-andreas.rheinhardt@gmail.com> MIME-Version: 1.0 Subject: [FFmpeg-devel] [PATCH 12/21] avcodec/smacker: Remove redundant check when decoding header trees X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Cc: Andreas Rheinhardt Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" When length is zero for a leaf node (which happens iff the Huffman tree consists of one leaf node only), prefix is also automatically zero. Performance impact is negligible: For GCC 9 and the sample from #2425, the time for one call to smka_decode_frame() decreased from 2053758 to 2053671 decicycles; for Clang 9 it went from 1523153 to 1521288. Signed-off-by: Andreas Rheinhardt --- libavcodec/smacker.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/libavcodec/smacker.c b/libavcodec/smacker.c index c249ce7514..991622eb0e 100644 --- a/libavcodec/smacker.c +++ b/libavcodec/smacker.c @@ -105,13 +105,8 @@ static int smacker_decode_tree(GetBitContext *gb, HuffContext *hc, uint32_t pref av_log(NULL, AV_LOG_ERROR, "Tree size exceeded!\n"); return AVERROR_INVALIDDATA; } - if(length){ - hc->bits[hc->current] = prefix; - hc->lengths[hc->current] = length; - } else { - hc->bits[hc->current] = 0; - hc->lengths[hc->current] = 0; - } + hc->bits[hc->current] = prefix; + hc->lengths[hc->current] = length; hc->values[hc->current] = get_bits(gb, 8); hc->current++; return 0;