From patchwork Tue Aug 8 23:06:32 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luc Van Oostenryck X-Patchwork-Id: 9889239 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 7B00D603F2 for ; Tue, 8 Aug 2017 23:07:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6E39F2891C for ; Tue, 8 Aug 2017 23:07:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6327128958; Tue, 8 Aug 2017 23:07:03 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.3 required=2.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, RCVD_IN_SORBS_SPAM, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0294028951 for ; Tue, 8 Aug 2017 23:07:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752522AbdHHXHB (ORCPT ); Tue, 8 Aug 2017 19:07:01 -0400 Received: from mail-wm0-f67.google.com ([74.125.82.67]:34813 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752521AbdHHXG7 (ORCPT ); Tue, 8 Aug 2017 19:06:59 -0400 Received: by mail-wm0-f67.google.com with SMTP id x64so4929589wmg.1 for ; Tue, 08 Aug 2017 16:06:59 -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; bh=2qpZVE2L8KX1ESz5+DrPD/tG8rILq8qJvYA/cI3IYKA=; b=g0IQXuw/r1lwEv/BrueUAkyB/0FxF8XkQdH8EIWdLaMy2pkmmd7mySmMEkNVKm7A1u 3Cz7LO4noWr1snW2OaitvxZJnuxZ1wKKfmDkeJhmK0Kzh2kezwciofh9P4u7F4X//62i Kz6nHprKoSlpHheh2qNJJXiQJdwAwcjKNAuz/LpfOZxPn1dvcjtF+TFJ2B42jo9HTjLH vCdgbOzEomAt/+l/vBnyK+mLMV82Tp5L3kRL+NwYzqLm2IY9XcakgpV4cqxkMre2r8Oz Rk+DPak6BeV2epeF4S/SBb9ohVconwIamo9O6fuZaERB4WXBCRK26tpcE/w9p+LUz32P gsvA== 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; bh=2qpZVE2L8KX1ESz5+DrPD/tG8rILq8qJvYA/cI3IYKA=; b=AkMijMFtDAZ/WvOu6HO0DyxHSiHBJbyk9XrB0DFELuI0A58LxpXITyUi9Js+FZE7Pa y14ddD1NM3s//vzT5kD2DNjDfNwyK1JXLfqNZBQt9286xlyPpOj0kpDPPuEfCfC+NdkX OGucA6bFiss6A3i22T0thQnQlgrolx9rKqKKxI5hAgRuOHKIyAhhujps2o0FV8M/5qEN 7xigXJhWGGJyAmlRTUN6XtvnIuufdNQV6PYuTw6WxDN2YMDumwFPOCFmQ4oEa1TcFC23 NbvCHAfbk+QLyjY86475KEFOgskTIuzPvc7WjfJGvKqxUV0X6bLF5v1dYo+o5ZwGmukW 3U5Q== X-Gm-Message-State: AHYfb5hlBKLTmTf1oDRIXn4qi7ARZW0ibAH/ca8inNlVufZQJEjUAHkb b+bRZMrobg3YZmWc/S4= X-Received: by 10.80.170.213 with SMTP id r21mr6192609edc.208.1502233618472; Tue, 08 Aug 2017 16:06:58 -0700 (PDT) Received: from localhost.localdomain ([2a02:a03f:4076:600:6494:649b:1a34:f1b]) by smtp.gmail.com with ESMTPSA id n15sm1133490edb.87.2017.08.08.16.06.57 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 08 Aug 2017 16:06:57 -0700 (PDT) From: Luc Van Oostenryck To: linux-sparse@vger.kernel.org Cc: Christopher Li , Linus Torvalds , Dibyendu Majumdar , Luc Van Oostenryck Subject: [PATCH v3 6/8] transform (A & M) >> S to (A >> S) & (M >> S) Date: Wed, 9 Aug 2017 01:06:32 +0200 Message-Id: <20170808230634.16227-7-luc.vanoostenryck@gmail.com> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20170808230634.16227-1-luc.vanoostenryck@gmail.com> References: <20170808230634.16227-1-luc.vanoostenryck@gmail.com> Sender: linux-sparse-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sparse@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This is especially usefull when simplifying code accessing bitfields. Signed-off-by: Luc Van Oostenryck --- simplify.c | 29 ++++++++++++++++++++++++++++- validation/bitfield-size.c | 4 +--- 2 files changed, 29 insertions(+), 4 deletions(-) diff --git a/simplify.c b/simplify.c index 9893613da..f1a898700 100644 --- a/simplify.c +++ b/simplify.c @@ -412,6 +412,32 @@ static int simplify_asr(struct instruction *insn, pseudo_t pseudo, long long val return 0; } +static int simplify_lsr(struct instruction *insn, pseudo_t pseudo, long long value) +{ + struct instruction *def; + unsigned long long mask; + + if (!value) + return replace_with_pseudo(insn, pseudo); + switch (def_opcode(insn->src1)) { + case OP_AND: + // replace (A & M) >> S + // by (A >> S) & (M >> S) + def = insn->src1->def; + if (!constant(def->src2)) + break; + if (nbr_pseudo_users(insn->src1) > 1) + break; + mask = def->src2->value; + def->opcode = OP_LSR; + def->src2 = value_pseudo(value); + insn->opcode = OP_AND; + insn->src2 = value_pseudo(mask >> value); + return REPEAT_CSE; + } + return 0; +} + static int simplify_mul_div(struct instruction *insn, long long value) { unsigned long long sbit = 1ULL << (insn->size - 1); @@ -562,13 +588,14 @@ static int simplify_constant_rightside(struct instruction *insn) case OP_ADD: case OP_OR: case OP_XOR: case OP_SHL: - case OP_LSR: case_neutral_zero: if (!value) return replace_with_pseudo(insn, insn->src1); return 0; case OP_ASR: return simplify_asr(insn, insn->src1, value); + case OP_LSR: + return simplify_lsr(insn, insn->src1, value); case OP_MODU: case OP_MODS: if (value == 1) diff --git a/validation/bitfield-size.c b/validation/bitfield-size.c index c8c94bb15..34400479a 100644 --- a/validation/bitfield-size.c +++ b/validation/bitfield-size.c @@ -36,8 +36,6 @@ unsigned int get_pbfi_b(struct bfi *bf) { return bf->b; } * check-output-ignore * * check-output-excludes: cast\\.4 - * check-output-pattern-6-times: cast\\. * check-output-pattern-6-times: lsr\\..*\\$6 - * check-output-pattern-6-times: and\\..*\\$15 - * check-output-pattern-6-times: and\\..*\\$960 + * check-output-pattern-12-times: and\\..*\\$15 */