From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C54B4C83001 for ; Thu, 30 Apr 2020 07:52:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A58A7214D8 for ; Thu, 30 Apr 2020 07:52:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="k8eTHxpg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726842AbgD3HwK (ORCPT ); Thu, 30 Apr 2020 03:52:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55004 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726815AbgD3HwH (ORCPT ); Thu, 30 Apr 2020 03:52:07 -0400 Received: from mail-qv1-xf4a.google.com (mail-qv1-xf4a.google.com [IPv6:2607:f8b0:4864:20::f4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 174A2C08E859 for ; Thu, 30 Apr 2020 00:52:07 -0700 (PDT) Received: by mail-qv1-xf4a.google.com with SMTP id et5so5577800qvb.5 for ; Thu, 30 Apr 2020 00:52:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=8jb1TKGtNOzFJaH+zGkIw1wrutaG9liyHI83TX/6kqM=; b=k8eTHxpgQuzrJ9uQslU4BZkP1qjy695olgk/kD7st0FbBQS9QYbG+4QhDv/8c9X93g iXERyX/zBA1PE6iznnzmz73WGdxip3vmtU+zHbcscEbtiSkev5iRp2nDCZ33put7DWXx fC8tpxUMk2WWQHeoaCbInHLtfJ8T3LGFzGHHFwkkGJhLZVXVd5BhSV4SmaGkqK+NVbwN RE7aq7Fcx7pLSpCn8g4WhikjCK/B0QRJA+TRMMbsTYyzeEF8+WqXaOyv61Iq8fuo6kNQ j9hVDA02cHuhrLQ5i4hnva8AFJROWpyIvuXkvFwmVYR38qTHLcQ3l/vuuflh+kpAIsXU jsng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=8jb1TKGtNOzFJaH+zGkIw1wrutaG9liyHI83TX/6kqM=; b=AQX8SnNFBxLkMx8PyyQP6i8dAEKITwD2RX5Uayg2LpwibhUboOKXSRDkOgiD8XJPEz nAI7NOYqc8X9Rslg9RfxE5o4egmWI+5KLap/9czDiOID137SGVTNjCP5D9uYY7Q3weW6 9N8Ik+lnjeTkYjPL1veSIic2RmRjFx9FiekuLolwBA071IZZBwlDjNtMzlCi3PO9noju JmMTB2S+xHVqGX7uhYMzeG7BzVM8h6IG0b0b8fvWC+8c8QGTMjG9chg51cqQkyV+3Reg uvTrFugqc8NQtIbrnCc1C+4k8BPkstpP8Bae1U3ptZT4MYwfrLh9lmKKj8858gJE3wRi jbdA== X-Gm-Message-State: AGi0PuZkaGLy2lrd+LESwbSdGjTe8wK1JVxGtfbQHB0LA4foPL9NMrWN qqm5A/Zbs915vT/XstR9eYgQpNUyUxuC X-Google-Smtp-Source: APiQypJbx+AsTfv2WcA4VEbGnEOcx6a6Rp0MiE4H3CaO6J5uiyFDgN0xh6jdmpHTjVojbQr5zfV2dfywL3rZ X-Received: by 2002:ad4:42c7:: with SMTP id f7mr1750659qvr.127.1588233126251; Thu, 30 Apr 2020 00:52:06 -0700 (PDT) Date: Thu, 30 Apr 2020 00:51:42 -0700 In-Reply-To: <20200430075144.132716-1-irogers@google.com> Message-Id: <20200430075144.132716-11-irogers@google.com> Mime-Version: 1.0 References: <20200430075144.132716-1-irogers@google.com> X-Mailer: git-send-email 2.26.2.303.gf8c07b1a785-goog Subject: [PATCH v3 10/12] perf expr: print a debug message for division by zero From: Ian Rogers To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Kan Liang , Andi Kleen , Haiyan Song , Jin Yao , Song Liu , Ravi Bangoria , John Garry , Leo Yan , Adrian Hunter , Paul Clarke , linux-kernel@vger.kernel.org, kajoljain , linux-perf-users@vger.kernel.org Cc: Stephane Eranian , Ian Rogers Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If an expression yields 0 and is then divided-by/modulus-by then the parsing aborts. Add a debug error message to better enable debugging when this happens. Signed-off-by: Ian Rogers --- tools/perf/util/expr.y | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/expr.y b/tools/perf/util/expr.y index 54260094b947..21e82a1e11a2 100644 --- a/tools/perf/util/expr.y +++ b/tools/perf/util/expr.y @@ -103,8 +103,18 @@ expr: NUMBER | expr '+' expr { $$ = $1 + $3; } | expr '-' expr { $$ = $1 - $3; } | expr '*' expr { $$ = $1 * $3; } - | expr '/' expr { if ($3 == 0) YYABORT; $$ = $1 / $3; } - | expr '%' expr { if ((long)$3 == 0) YYABORT; $$ = (long)$1 % (long)$3; } + | expr '/' expr { if ($3 == 0) { + pr_debug("division by zero\n"); + YYABORT; + } + $$ = $1 / $3; + } + | expr '%' expr { if ((long)$3 == 0) { + pr_debug("division by zero\n"); + YYABORT; + } + $$ = (long)$1 % (long)$3; + } | '-' expr %prec NEG { $$ = -$2; } | '(' if_expr ')' { $$ = $2; } | MIN '(' expr ',' expr ')' { $$ = $3 < $5 ? $3 : $5; } -- 2.26.2.303.gf8c07b1a785-goog