From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pj1-x1029.google.com (mail-pj1-x1029.google.com [IPv6:2607:f8b0:4864:20::1029]) by sourceware.org (Postfix) with ESMTPS id 4AA30385828C for ; Mon, 7 Nov 2022 22:08:01 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 4AA30385828C Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=dabbelt.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=dabbelt.com Received: by mail-pj1-x1029.google.com with SMTP id d59-20020a17090a6f4100b00213202d77e1so16092956pjk.2 for ; Mon, 07 Nov 2022 14:08:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dabbelt-com.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:to:from:cc :in-reply-to:subject:date:from:to:cc:subject:date:message-id :reply-to; bh=WKPd/CAAitivQJzTZFIXssQ9cb40KGl6CMPGttUYRJ0=; b=jagcnnB8MzCgOGTP/huO3zdIPskSj7uzaAr/SJsgz4+CNdVxNIjOVkjaPE/A3Po8lD 03ZPhY/UwWV9+yiIxYX+dgXrXV8fzPSsrobZoAUvEf7HyXbG3uTczVj6lQZkAoTOM0PE kRk17h6YYW6CVXNrIk9Dxrt6Eh4KNBFwCSLclzKqcmh7aUAaU4Pwgng950KyfNQWzGk0 yMtoAy6m/oZdPYG6PEyhyBnah8RbJ0K0JNetGytMrk/9CPo7ZVsnDeJjDwJQYPy0AYAe sdz7yQ2YxdxW3JGfG/DVO+V2Vt0XUlcZcMXaFdwiwesjrKvIwj5aE99WYSqx5/K5kmcu GY3A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:to:from:cc :in-reply-to:subject:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=WKPd/CAAitivQJzTZFIXssQ9cb40KGl6CMPGttUYRJ0=; b=aN8exYTgCe4HTgNmUNIp2H8WEhZ5J4Knbn3crkoQtgLYMNj9df2HwS2y8clkhXiaie +YjljbeK7GmmI9RttE0U7D5i0m/4vTFk9pvrjM1Dxmm8T0+0/oMN5uVOIF1WekZCFx96 L2BDk4YA6204m8EtwXxjkT4eRd1U2oTAmuutPplIR6LjYkUczKLytHTBiTSyBfYkgi+g avvvVVHKff63f2Nu7h4ZyqkTOhy+y2rpphe8sJ9DJ0AEVPRICD5Nk2axMMMtz9IMi/hm 9EnwWCdV4jELxCTlKb+Yq9Fo1ysKLZ+Z2C8MaW5/mlnDBV+J85ffIZa7YasOgpvdVjDE 6Eaw== X-Gm-Message-State: ACrzQf3ITXxxPGnNKJNx/UplJRzZ54ycBX1LQq0YQj8HCUhuIWeci+Ut slrwrNjUV6psJZWLZSS1QpdYHAxOPR+t7Q== X-Google-Smtp-Source: AMsMyM6jS1ZWV/+tJkpSO4KUkOckwYyDCayTn16Ig0/dBp9gis+3GaPrc58LclhpuySAtSYE26FkTw== X-Received: by 2002:a17:90a:b383:b0:216:df8f:3c3 with SMTP id e3-20020a17090ab38300b00216df8f03c3mr21837615pjr.8.1667858879463; Mon, 07 Nov 2022 14:07:59 -0800 (PST) Received: from localhost ([50.221.140.188]) by smtp.gmail.com with ESMTPSA id r11-20020a170902c60b00b001830ed575c3sm5416964plr.117.2022.11.07.14.07.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Nov 2022 14:07:58 -0800 (PST) Date: Mon, 07 Nov 2022 14:07:58 -0800 (PST) X-Google-Original-Date: Mon, 07 Nov 2022 14:07:55 PST (-0800) Subject: Re: [PATCH] Enable shrink wrapping for the RISC-V target. In-Reply-To: CC: gcc-patches@gcc.gnu.org, Vineet Gupta , Kito Cheng , philipp.tomsich@vrull.eu From: Palmer Dabbelt To: jlaw@ventanamicro.com Message-ID: Mime-Version: 1.0 (MHng) Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-4.8 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Thu, 03 Nov 2022 15:23:28 PDT (-0700), jlaw@ventanamicro.com wrote: > > On 11/2/22 18:26, Palmer Dabbelt wrote: >> >>>> I also tried to remove that restriction but it looks like it can't >>>> work because we can't create >>>> pseudo-registers during shrink wrapping and shrink wrapping can't >>>> work either. >>>> >>>> I believe this means that shrink wrapping cannot interfere with a long >>>> stack frame >>>> so there is nothing to test against in this case? >>> >>> It'd be marginally better to have such a test case to ensure we don't >>> shrink wrap it -- that would ensure that someone doesn't accidentally >>> introduce shrink wrapping with large offsets.   Just a bit of future >>> proofing. >> >> If there's passing test cases that fail with that check removed then >> it's probably good enough, though I think in this case just having a >> comment there saying why the short-stack check is necessary should be >> fine. > > I can live with this. Which one (or either)? I'm fine with either option, just trying to avoid another re-spin as this one is a bit vague.