From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id 9AFE538582BF for ; Mon, 26 Sep 2022 17:24:52 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 9AFE538582BF Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1664213092; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=FSdMGyNqojanvG4K38b10gQ4xk2xJqYVUlhlLbFwsJU=; b=aH4a/A8ezlA8qz4nhht5qHh8QcnJmfULa5ku6XtTDg50u8cgVN0F31o6iEaNrbjpnR5M6b 8HmLOfQP9HB1Wvf2Ula9F5PtwTcCTbKhN8Pbln+S2FixL3JJtHM8PgqHS6iqgaaIEfatjG UpW8TMUPczKsDJNGsVbK4PntdKGXnYQ= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-13-bLJjZqeJMjihm8iB-ngX4w-1; Mon, 26 Sep 2022 13:24:50 -0400 X-MC-Unique: bLJjZqeJMjihm8iB-ngX4w-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 504373817964 for ; Mon, 26 Sep 2022 17:24:50 +0000 (UTC) Received: from abulafia.quesejoda.com (unknown [10.39.195.119]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E1FDF492B05; Mon, 26 Sep 2022 17:24:49 +0000 (UTC) Received: from abulafia.quesejoda.com (localhost [127.0.0.1]) by abulafia.quesejoda.com (8.17.1/8.17.1) with ESMTPS id 28QHOltD3219498 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Mon, 26 Sep 2022 19:24:47 +0200 Received: (from aldyh@localhost) by abulafia.quesejoda.com (8.17.1/8.17.1/Submit) id 28QHOln73219497; Mon, 26 Sep 2022 19:24:47 +0200 From: Aldy Hernandez To: GCC patches Cc: Andrew MacLeod , Aldy Hernandez Subject: [COMMITTED] Optimize [0 = x & MASK] in range-ops. Date: Mon, 26 Sep 2022 19:24:41 +0200 Message-Id: <20220926172441.3219466-1-aldyh@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII"; x-default=true X-Spam-Status: No, score=-12.3 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,GIT_PATCH_0,RCVD_IN_DNSWL_LOW,SPF_HELO_NONE,SPF_NONE,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: For [0 = x & MASK], we can determine that x is ~MASK. This is something we're picking up in DOM thanks to maybe_set_nonzero_bits, but is something we should handle natively. This is a good example of how much easier to maintain the range-ops entries are versus the ad-hoc pattern matching stuff we had to do before. For the curious, compare the changes to range-op here, versus maybe_set_nonzero_bits. I'm leaving the call to maybe_set_nonzero_bits until I can properly audit it to make sure we're catching it all in range-ops. It won't hurt, since both set_range_info() and set_nonzero_bits() are intersect operations, so we'll never lose information if we do both. Tested on x86-64 Linux. PR tree-optimization/107009 gcc/ChangeLog: * range-op.cc (operator_bitwise_and::op1_range): Optimize 0 = x & MASK. (range_op_bitwise_and_tests): New test. --- gcc/range-op.cc | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/gcc/range-op.cc b/gcc/range-op.cc index 072ebd32109..fc930f4d613 100644 --- a/gcc/range-op.cc +++ b/gcc/range-op.cc @@ -2951,6 +2951,15 @@ operator_bitwise_and::op1_range (irange &r, tree type, } if (r.undefined_p ()) set_nonzero_range_from_mask (r, type, lhs); + + // For 0 = op1 & MASK, op1 is ~MASK. + if (lhs.zero_p () && op2.singleton_p ()) + { + wide_int nz = wi::bit_not (op2.get_nonzero_bits ()); + int_range<2> tmp (type); + tmp.set_nonzero_bits (nz); + r.intersect (tmp); + } return true; } @@ -4612,6 +4621,15 @@ range_op_bitwise_and_tests () op_bitwise_and.op1_range (res, integer_type_node, i1, i2); ASSERT_TRUE (res == int_range<1> (integer_type_node)); + // For 0 = x & MASK, x is ~MASK. + { + int_range<2> zero (integer_zero_node, integer_zero_node); + int_range<2> mask = int_range<2> (INT (7), INT (7)); + op_bitwise_and.op1_range (res, integer_type_node, zero, mask); + wide_int inv = wi::shwi (~7U, TYPE_PRECISION (integer_type_node)); + ASSERT_TRUE (res.get_nonzero_bits () == inv); + } + // (NONZERO | X) is nonzero. i1.set_nonzero (integer_type_node); i2.set_varying (integer_type_node); -- 2.37.1