From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 12062 invoked by alias); 19 Aug 2019 11:01:18 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 11866 invoked by uid 89); 19 Aug 2019 11:01:18 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-8.1 required=5.0 tests=AWL,BAYES_00,FREEMAIL_ENVFROM_END_DIGIT,FREEMAIL_FROM,KAM_NUMSUBJECT,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=no version=3.3.1 spammy=HX-HELO:sk:mail-ed, HX-Received:906, Tejas, complications X-HELO: mail-ed1-f54.google.com Received: from mail-ed1-f54.google.com (HELO mail-ed1-f54.google.com) (209.85.208.54) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Mon, 19 Aug 2019 11:01:17 +0000 Received: by mail-ed1-f54.google.com with SMTP id g8so1261835edm.6 for ; Mon, 19 Aug 2019 04:01:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to:cc; bh=Qdcz/9pPfLMG+NshF9VPG/NxCShisDkzQ1PWTNaXEFs=; b=LBul+hM1pqoGEVfXK0Dm9qPlssC5TcVHPkE/LFk8x/jrA2vUKtPkhssQn8Kmz1ljZz tzy2ipSuzVL7lDCvB/7M/OE97g+J5SiI+URbMoLwP1RohBl7K8dXmOmMJjsXQoAXpy5s eEpIA2KE5hUFEQyCi7yPnWa+WsLMK5/aHcYfJprnG76q7YSh5F/ziM3EGb0HbSmjnhcP KepSjrI8/Yzdu2A9u2VTePja/gMwqeSyAxCal6Enx7RhziO6jgrwz0ZKID2y5t/S3Wav l9qE8QnRHER/EwWPvgKEFKrP0EKXL8QCFdXandGzMAPtFsGGNW5C3owAcu57ARohO+no Ekmw== MIME-Version: 1.0 From: Tejas Joshi Date: Mon, 19 Aug 2019 11:01:00 -0000 Message-ID: Subject: [GSoC-19] Expanding fromfp variants on AArch64 To: gcc@gcc.gnu.org Cc: Martin Jambor , hubicka@ucw.cz, joseph@codesourcery.com Content-Type: text/plain; charset="UTF-8" X-IsSubscribed: yes X-SW-Source: 2019-08/txt/msg00132.txt.bz2 Hello. The fromfp/fromfpx variants round to integers with a specified number of bits, to a specified rounding mode. They come with their own complications as Joseph had stated in an initial mail and expected to expand them in AArch64 : > The fromfp / fromfpx / ufromfp / ufromfpx functions (round to integers > of a specified number of bits, in a specified rounding mode, with > specified handling of inexact results) are a case with some other > complications. Typically I'd expect them to be expanded inline only (for > constant arguments or) for constant values of the number of bits and > rounding mode, if the target machine has an appropriate instruction. A > target hook would need adding for a target to specify the FP_INT_* values > used in libm, since that's an ABI that's defined by libm, not by GCC. > Then you'd need instruction patterns that might only be supported in > certain cases. How can I add a target hook to specify the FP_INT_* values from libm ? Also as this includes rounding to integers, does it involve any RTL related complications that we have encountered in FADD ? Thanks, Tejas