From patchwork Wed Aug 9 19:38:03 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: 9891731 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 89606602D7 for ; Wed, 9 Aug 2017 19:39:07 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7B2D02832D for ; Wed, 9 Aug 2017 19:39:07 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 702D828672; Wed, 9 Aug 2017 19:39:07 +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 058B42832D for ; Wed, 9 Aug 2017 19:39:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751927AbdHITjG (ORCPT ); Wed, 9 Aug 2017 15:39:06 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:33837 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751884AbdHITjG (ORCPT ); Wed, 9 Aug 2017 15:39:06 -0400 Received: by mail-wm0-f65.google.com with SMTP id x64so618341wmg.1 for ; Wed, 09 Aug 2017 12:39:05 -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=W+C7mnF77E+MoTsUqsubfVe7e+OmobOq8JrZUl2Edew=; b=hhSRFMdTmxHUaxvODL0hqPSkYz78gZuR+sEdyawJZzaTuovATCdilFBtHKSfoxgJtj y9DSqANuJmFt40pXuXQFjDFvejxqU0M1a59UwWetxdAjPK2BTcc/n/DAmFOCJ7Dm+8ss 809564EUnhLZobFwqtCnXyVYiBfEdK8ZK6w5qthRotRJSkCANxTt5vL8ASTjiPKIMNRb JQEhC8GetElW4RvsmH17qiK5GfdXGgglJTsY2fBcT3Wfbg3PEuFkyvamZqCO7yuqMvwi b7l4VZIOT0MtkGjni0ZOPqi3gV+bZpEHbhH7fytEcvyzbOAvFDYRDJAqFooQphhTj/sv 7nqQ== 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=W+C7mnF77E+MoTsUqsubfVe7e+OmobOq8JrZUl2Edew=; b=fdMw93bWdWScFk9iPaXSqBQqI236TRdlQiioDo+Xse+iP+IYkhF30BhRYOwk2bIbsz iH/Qcvc2qQG09uEohToZ75h4sn0ZHBrG4WdnY00MgYAiHaPP1UQ+uERCbHsiaqb0sVF9 jcnKK/BMggXdottvHcckLfPyPf40/8nFwgZesRPNspix3KbSJ0MkcWxT/8y/iouZHop5 4jc3DTvgvgpVfzvJLOad2OsS2dct9fpGORQxPe+KpvFM8nx4CBm7fFsfHySVR2xPtpdl Z4l0OxLXSnoZ6aPNPX7ncc5ocT7lB6/PBjJBydqUyj/UYNdOKCbY/lmNN/pKl4CpBBUU qTVA== X-Gm-Message-State: AHYfb5jNB9RYhYgI94NP2wecXtJvvp89X4wGj76w5RV8pCrPDn1S2PtS z0y0hPq1ca8nBa+F9fg= X-Received: by 10.80.224.135 with SMTP id f7mr9094049edl.202.1502307544620; Wed, 09 Aug 2017 12:39:04 -0700 (PDT) Received: from localhost.localdomain ([2a02:a03f:4076:600:a54f:2a42:70ce:5bd2]) by smtp.gmail.com with ESMTPSA id t36sm2984437edb.38.2017.08.09.12.39.03 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 09 Aug 2017 12:39:04 -0700 (PDT) From: Luc Van Oostenryck To: linux-sparse@vger.kernel.org Cc: Christopher Li , Luc Van Oostenryck Subject: [PATCH v4 6/9] simplify ((A & M') | B ) & M when M' & M == 0 Date: Wed, 9 Aug 2017 21:38:03 +0200 Message-Id: <20170809193806.30975-7-luc.vanoostenryck@gmail.com> X-Mailer: git-send-email 2.14.0 In-Reply-To: <20170809193806.30975-1-luc.vanoostenryck@gmail.com> References: <20170809193806.30975-1-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 specially usefull when A is in fact undefined. Reported-by: Dibyendu Majumdar Signed-off-by: Luc Van Oostenryck --- simplify.c | 42 +++++++++++++++++++++- validation/optim/store-load-bitfield.c | 66 ++++++++++++++++++++++++++++++++++ 2 files changed, 107 insertions(+), 1 deletion(-) create mode 100644 validation/optim/store-load-bitfield.c diff --git a/simplify.c b/simplify.c index 30961cf39..40d4f0068 100644 --- a/simplify.c +++ b/simplify.c @@ -501,6 +501,46 @@ static int simplify_seteq_setne(struct instruction *insn, long long value) } } +static int simplify_and_or_mask(struct instruction *insn, pseudo_t and, pseudo_t other, unsigned long long mask) +{ + struct instruction *def = and->def; + pseudo_t old; + + if (!constant(def->src2)) + return 0; + if (def->src2->value & mask) + return 0; + old = insn->src1; + use_pseudo(insn, other, &insn->src1); + remove_usage(old, &insn->src1); + return REPEAT_CSE; +} + +static int simplify_constant_mask(struct instruction *insn, unsigned long long mask) +{ + struct instruction *left; + pseudo_t src1, src2; + + switch (def_opcode(insn->src1)) { + case OP_OR: + // Let's handle ((A & M') | B ) & M + // or (B | (A & M')) & M + // when M' & M == 0 + left = insn->src1->def; + src1 = left->src1; + src2 = left->src2; + if (def_opcode(src1) == OP_AND) + return simplify_and_or_mask(insn, src1, src2, mask); + if (def_opcode(src2) == OP_AND) + return simplify_and_or_mask(insn, src2, src1, mask); + break; + + default: + break; + } + return 0; +} + static int simplify_constant_rightside(struct instruction *insn) { long long value = insn->src2->value; @@ -545,7 +585,7 @@ static int simplify_constant_rightside(struct instruction *insn) case OP_AND: if (!value) return replace_with_pseudo(insn, insn->src2); - return 0; + return simplify_constant_mask(insn, value); case OP_SET_NE: case OP_SET_EQ: diff --git a/validation/optim/store-load-bitfield.c b/validation/optim/store-load-bitfield.c new file mode 100644 index 000000000..b74022602 --- /dev/null +++ b/validation/optim/store-load-bitfield.c @@ -0,0 +1,66 @@ +int ufoo(int a) +{ + struct u { + unsigned int :2; + unsigned int a:3; + } bf; + + bf.a = a; + return bf.a; +} + +int sfoo(int a) +{ + struct s { + signed int :2; + signed int a:3; + } bf; + + bf.a = a; + return bf.a; +} + +int xfoo(int a) +{ + struct x { + int :2; + int a:3; // unsigned ! + } bf; + + bf.a = a; + return bf.a; +} + + +/* + * check-name: optim store/load bitfields + * check-command: test-linearize -Wno-decl $file + * + * check-output-start +ufoo: +.L0: + + scast.3 %r2 <- (32) %arg1 + and.32 %r9 <- %r2, $7 + ret.32 %r9 + + +sfoo: +.L2: + + scast.3 %r13 <- (32) %arg1 + and.32 %r20 <- %r13, $7 + scast.32 %r21 <- (3) %r20 + ret.32 %r21 + + +xfoo: +.L4: + + scast.3 %r24 <- (32) %arg1 + and.32 %r31 <- %r24, $7 + ret.32 %r31 + + + * check-output-end + */