From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dedi548.your-server.de (dedi548.your-server.de [85.10.215.148]) by sourceware.org (Postfix) with ESMTPS id E351F388EC1E for ; Mon, 19 Oct 2020 16:05:29 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org E351F388EC1E Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=embedded-brains.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=sebastian.huber@embedded-brains.de Received: from sslproxy02.your-server.de ([78.47.166.47]) by dedi548.your-server.de with esmtpsa (TLSv1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.92.3) (envelope-from ) id 1kUXf6-0004Ot-Uw for newlib@sourceware.org; Mon, 19 Oct 2020 18:05:28 +0200 Received: from [82.100.198.138] (helo=mail.embedded-brains.de) by sslproxy02.your-server.de with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.92) (envelope-from ) id 1kUXf1-0002og-Rk for newlib@sourceware.org; Mon, 19 Oct 2020 18:05:23 +0200 Received: from localhost (localhost.localhost [127.0.0.1]) by mail.embedded-brains.de (Postfix) with ESMTP id 8937E2A1610 for ; Mon, 19 Oct 2020 18:04:11 +0200 (CEST) Received: from mail.embedded-brains.de ([127.0.0.1]) by localhost (zimbra.eb.localhost [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id Geg-eY4PxB4Z for ; Mon, 19 Oct 2020 18:04:10 +0200 (CEST) Received: from localhost (localhost.localhost [127.0.0.1]) by mail.embedded-brains.de (Postfix) with ESMTP id 955BD2A1687 for ; Mon, 19 Oct 2020 18:04:10 +0200 (CEST) X-Virus-Scanned: amavisd-new at zimbra.eb.localhost Received: from mail.embedded-brains.de ([127.0.0.1]) by localhost (zimbra.eb.localhost [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id VUFra5GUPGSG for ; Mon, 19 Oct 2020 18:04:10 +0200 (CEST) Received: from linux-diu0.suse (unknown [192.168.96.161]) by mail.embedded-brains.de (Postfix) with ESMTP id 744CE2A1688 for ; Mon, 19 Oct 2020 18:04:10 +0200 (CEST) From: Sebastian Huber To: newlib@sourceware.org Subject: [PATCH 06/11] To reduce the size of an rb_node, drop the color Date: Mon, 19 Oct 2020 18:05:19 +0200 Message-Id: <20201019160522.15408-7-sebastian.huber@embedded-brains.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201019160522.15408-1-sebastian.huber@embedded-brains.de> References: <20201019160522.15408-1-sebastian.huber@embedded-brains.de> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Authenticated-Sender: smtp-embedded@poldinet.de X-Virus-Scanned: Clear (ClamAV 0.102.4/25962/Mon Oct 19 15:57:02 2020) X-Spam-Status: No, score=-12.0 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: newlib@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Newlib mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 19 Oct 2020 16:05:32 -0000 From: dougm field. Set the least significant bit in the pointer to the node from its = parent to indicate that the node is red. Have the tree rotation macros leave the old-parent/new-child node red and the new-parent/old-child node black. This change makes RB_LEFT and RB_RIGHT no longer assignable, and RB_COLOR no longer defined. Any code that modifies the tree or examines a node color would have to be modified after this change. Reviewed by: markj Tested by: pho Differential Revision: https://reviews.freebsd.org/D25105 --- newlib/libc/include/sys/tree.h | 281 +++++++++++++++++---------------- 1 file changed, 143 insertions(+), 138 deletions(-) diff --git a/newlib/libc/include/sys/tree.h b/newlib/libc/include/sys/tre= e.h index 372c001b9..29b731822 100644 --- a/newlib/libc/include/sys/tree.h +++ b/newlib/libc/include/sys/tree.h @@ -307,34 +307,31 @@ struct name { \ (root)->rbh_root =3D NULL; \ } while (/*CONSTCOND*/ 0) =20 -#define RB_BLACK 0 -#define RB_RED 1 #define RB_ENTRY(type) \ struct { \ struct type *rbe_left; /* left element */ \ struct type *rbe_right; /* right element */ \ struct type *rbe_parent; /* parent element */ \ - int rbe_color; /* node color */ \ } =20 -#define RB_LEFT(elm, field) (elm)->field.rbe_left -#define RB_RIGHT(elm, field) (elm)->field.rbe_right +#define RB_LF(elm, field) (elm)->field.rbe_left +#define RB_RT(elm, field) (elm)->field.rbe_right +#define RB_FLIP(elm) (*(__uintptr_t *)&(elm) ^=3D 1) +#define RB_FLIP_LF(elm, field) RB_FLIP(RB_LF(elm, field)) +#define RB_FLIP_RT(elm, field) RB_FLIP(RB_RT(elm, field)) +#define RB_ISRED(elm) ((*(__uintptr_t *)&(elm) & 1) !=3D 0) +#define RB_RED_LF(elm, field) RB_ISRED(RB_LF(elm, field)) +#define RB_RED_RT(elm, field) RB_ISRED(RB_RT(elm, field)) +#define RB_PTR(elm, field) ((__typeof(elm->field.rbe_parent)) \ + ((__uintptr_t)(elm) & ~(__uintptr_t)1)) +#define RB_LEFT(elm, field) RB_PTR(RB_LF(elm, field), field) +#define RB_RIGHT(elm, field) RB_PTR(RB_RT(elm, field), field) #define RB_PARENT(elm, field) (elm)->field.rbe_parent -#define RB_COLOR(elm, field) (elm)->field.rbe_color -#define RB_ISRED(elm, field) ((elm) !=3D NULL && RB_COLOR(elm, field) =3D= =3D RB_RED) #define RB_ROOT(head) (head)->rbh_root #define RB_EMPTY(head) (RB_ROOT(head) =3D=3D NULL) - -#define RB_SET(elm, parent, field) do { \ - RB_PARENT(elm, field) =3D parent; \ - RB_LEFT(elm, field) =3D RB_RIGHT(elm, field) =3D NULL; \ - RB_COLOR(elm, field) =3D RB_RED; \ -} while (/*CONSTCOND*/ 0) - -#define RB_SET_BLACKRED(black, red, field) do { \ - RB_COLOR(black, field) =3D RB_BLACK; \ - RB_COLOR(red, field) =3D RB_RED; \ -} while (/*CONSTCOND*/ 0) +#define RB_BOOL int +#define RB_TRUE 1 +#define RB_FALSE 0 =20 /* * Something to be invoked in a loop at the root of every modified subtr= ee, @@ -344,37 +341,42 @@ struct { \ #define RB_AUGMENT(x) break #endif =20 +/* + * Fix pointers to a parent, and from a parent, as part of rotation. + */ +#define RB_ROTATE_PARENT(head, elm, tmp, field) do { \ + if ((RB_PARENT(tmp, field) =3D RB_PARENT(elm, field)) =3D=3D NULL) \ + RB_ROOT(head) =3D (tmp); \ + else if ((elm) =3D=3D RB_LEFT(RB_PARENT(elm, field), field)) \ + RB_LF(RB_PARENT(elm, field), field) =3D (tmp); \ + else \ + RB_RT(RB_PARENT(elm, field), field) =3D (tmp); \ + RB_PARENT(elm, field) =3D (tmp); \ +} while (/*CONSTCOND*/ 0) + +/* + * Rotation makes the descending node red, and the ascending + * node not-red. + */ #define RB_ROTATE_LEFT(head, elm, tmp, field) do { \ (tmp) =3D RB_RIGHT(elm, field); \ - if ((RB_RIGHT(elm, field) =3D RB_LEFT(tmp, field)) !=3D NULL) { \ + if ((RB_RT(elm, field) =3D RB_LF(tmp, field)) !=3D NULL) { \ RB_PARENT(RB_LEFT(tmp, field), field) =3D (elm); \ } \ - if ((RB_PARENT(tmp, field) =3D RB_PARENT(elm, field)) !=3D NULL) { \ - if ((elm) =3D=3D RB_LEFT(RB_PARENT(elm, field), field)) \ - RB_LEFT(RB_PARENT(elm, field), field) =3D (tmp); \ - else \ - RB_RIGHT(RB_PARENT(elm, field), field) =3D (tmp); \ - } else \ - (head)->rbh_root =3D (tmp); \ - RB_LEFT(tmp, field) =3D (elm); \ - RB_PARENT(elm, field) =3D (tmp); \ + RB_ROTATE_PARENT(head, elm, tmp, field); \ + RB_LF(tmp, field) =3D (elm); \ + RB_FLIP_LF(tmp, field); \ RB_AUGMENT(elm); \ } while (/*CONSTCOND*/ 0) =20 #define RB_ROTATE_RIGHT(head, elm, tmp, field) do { \ (tmp) =3D RB_LEFT(elm, field); \ - if ((RB_LEFT(elm, field) =3D RB_RIGHT(tmp, field)) !=3D NULL) { \ + if ((RB_LF(elm, field) =3D RB_RT(tmp, field)) !=3D NULL) { \ RB_PARENT(RB_RIGHT(tmp, field), field) =3D (elm); \ } \ - if ((RB_PARENT(tmp, field) =3D RB_PARENT(elm, field)) !=3D NULL) { \ - if ((elm) =3D=3D RB_LEFT(RB_PARENT(elm, field), field)) \ - RB_LEFT(RB_PARENT(elm, field), field) =3D (tmp); \ - else \ - RB_RIGHT(RB_PARENT(elm, field), field) =3D (tmp); \ - } else \ - (head)->rbh_root =3D (tmp); \ - RB_RIGHT(tmp, field) =3D (elm); \ - RB_PARENT(elm, field) =3D (tmp); \ + RB_ROTATE_PARENT(head, elm, tmp, field); \ + RB_RT(tmp, field) =3D (elm); \ + RB_FLIP_RT(tmp, field); \ RB_AUGMENT(elm); \ } while (/*CONSTCOND*/ 0) =20 @@ -439,110 +441,105 @@ struct { \ attr void \ name##_RB_INSERT_COLOR(struct name *head, struct type *elm) \ { \ - struct type *parent, *gparent, *tmp; \ - while (RB_ISRED((parent =3D RB_PARENT(elm, field)), field)) { \ - gparent =3D RB_PARENT(parent, field); \ - if (parent =3D=3D RB_LEFT(gparent, field)) { \ - tmp =3D RB_RIGHT(gparent, field); \ - if (RB_ISRED(tmp, field)) { \ - RB_COLOR(tmp, field) =3D RB_BLACK; \ - RB_SET_BLACKRED(parent, gparent, field);\ - elm =3D gparent; \ - continue; \ - } \ + struct type *gparent, *parent; \ + while ((parent =3D RB_PARENT(elm, field)) !=3D NULL) { \ + if (RB_LEFT(parent, field) =3D=3D elm) \ + RB_FLIP_LF(parent, field); \ + else \ + RB_FLIP_RT(parent, field); \ + if ((gparent =3D RB_PARENT(parent, field)) =3D=3D NULL) \ + break; \ + if (RB_RED_LF(gparent, field) && \ + RB_RED_RT(gparent, field)) { \ + RB_FLIP_LF(gparent, field); \ + RB_FLIP_RT(gparent, field); \ + elm =3D gparent; \ + continue; \ + } \ + if (RB_RED_LF(gparent, field) && \ + parent =3D=3D RB_LEFT(gparent, field)) { \ if (RB_RIGHT(parent, field) =3D=3D elm) { \ - RB_ROTATE_LEFT(head, parent, tmp, field);\ - tmp =3D parent; \ + RB_ROTATE_LEFT(head, parent, elm, field);\ parent =3D elm; \ - elm =3D tmp; \ - } \ - RB_SET_BLACKRED(parent, gparent, field); \ - RB_ROTATE_RIGHT(head, gparent, tmp, field); \ - } else { \ - tmp =3D RB_LEFT(gparent, field); \ - if (RB_ISRED(tmp, field)) { \ - RB_COLOR(tmp, field) =3D RB_BLACK; \ - RB_SET_BLACKRED(parent, gparent, field);\ - elm =3D gparent; \ - continue; \ } \ + RB_ROTATE_RIGHT(head, gparent, parent, field); \ + } else if (RB_RED_RT(gparent, field) && \ + parent =3D=3D RB_RIGHT(gparent, field)) { \ if (RB_LEFT(parent, field) =3D=3D elm) { \ - RB_ROTATE_RIGHT(head, parent, tmp, field);\ - tmp =3D parent; \ + RB_ROTATE_RIGHT(head, parent, elm, field);\ parent =3D elm; \ - elm =3D tmp; \ } \ - RB_SET_BLACKRED(parent, gparent, field); \ - RB_ROTATE_LEFT(head, gparent, tmp, field); \ + RB_ROTATE_LEFT(head, gparent, parent, field); \ } \ + break; \ } \ - RB_COLOR(head->rbh_root, field) =3D RB_BLACK; \ } =20 #define RB_GENERATE_REMOVE_COLOR(name, type, field, attr) \ attr void \ -name##_RB_REMOVE_COLOR(struct name *head, struct type *parent) \ +name##_RB_REMOVE_COLOR(struct name *head, struct type *elm) \ { \ - struct type *elm, *tmp; \ - elm =3D NULL; \ + struct type *par, *sib, *tmp; \ + RB_BOOL go_left, left_child, red_par; \ + left_child =3D (RB_LEFT(elm, field) =3D=3D NULL); \ do { \ - if (RB_LEFT(parent, field) =3D=3D elm) { \ - tmp =3D RB_RIGHT(parent, field); \ - if (RB_COLOR(tmp, field) =3D=3D RB_RED) { \ - RB_SET_BLACKRED(tmp, parent, field); \ - RB_ROTATE_LEFT(head, parent, tmp, field);\ - tmp =3D RB_RIGHT(parent, field); \ + go_left =3D left_child; \ + if (go_left ? \ + !RB_RED_RT(elm, field) : \ + !RB_RED_LF(elm, field)) { \ + par =3D RB_PARENT(elm, field); \ + left_child =3D par !=3D NULL && \ + RB_LEFT(par, field) =3D=3D elm; \ + red_par =3D left_child ? RB_RED_LF(par, field) : \ + par =3D=3D NULL ? RB_TRUE : \ + RB_RED_RT(par, field); \ + } \ + if (go_left) { \ + if (RB_RED_RT(elm, field)) { \ + red_par =3D RB_TRUE; \ + RB_ROTATE_LEFT(head, elm, par, field); \ } \ - if (RB_ISRED(RB_LEFT(tmp, field), field)) { \ - struct type *oleft; \ - oleft =3D RB_LEFT(tmp, field); \ - RB_COLOR(oleft, field) =3D RB_BLACK; \ - RB_COLOR(tmp, field) =3D RB_RED; \ - RB_ROTATE_RIGHT(head, tmp, oleft, field); \ - tmp =3D RB_RIGHT(parent, field); \ - } else if (!RB_ISRED(RB_RIGHT(tmp, field), field)) { \ - RB_COLOR(tmp, field) =3D RB_RED; \ - elm =3D parent; \ - parent =3D RB_PARENT(elm, field); \ + sib =3D RB_RIGHT(elm, field); \ + if (RB_RED_LF(sib, field)) { \ + RB_ROTATE_RIGHT(head, sib, tmp, field); \ + sib =3D tmp; \ + } else if (!RB_RED_RT(sib, field)) { \ + RB_FLIP_RT(elm, field); \ + elm =3D par; \ continue; \ } \ - if (RB_ISRED(RB_RIGHT(tmp, field), field)) \ - RB_COLOR(RB_RIGHT(tmp, field), field) =3D RB_BLACK; \ - RB_COLOR(tmp, field) =3D RB_COLOR(parent, field); \ - RB_COLOR(parent, field) =3D RB_BLACK; \ - RB_ROTATE_LEFT(head, parent, tmp, field); \ - elm =3D RB_ROOT(head); \ + if (RB_RED_RT(sib, field)) \ + RB_FLIP_RT(sib, field); \ + RB_ROTATE_LEFT(head, elm, sib, field); \ + RB_FLIP_LF(sib, field); \ break; \ } else { \ - tmp =3D RB_LEFT(parent, field); \ - if (RB_COLOR(tmp, field) =3D=3D RB_RED) { \ - RB_SET_BLACKRED(tmp, parent, field); \ - RB_ROTATE_RIGHT(head, parent, tmp, field);\ - tmp =3D RB_LEFT(parent, field); \ + if (RB_RED_LF(elm, field)) { \ + red_par =3D RB_TRUE; \ + RB_ROTATE_RIGHT(head, elm, par, field); \ } \ - if (RB_ISRED(RB_RIGHT(tmp, field), field)) { \ - struct type *oright; \ - oright =3D RB_RIGHT(tmp, field); \ - RB_COLOR(oright, field) =3D RB_BLACK; \ - RB_COLOR(tmp, field) =3D RB_RED; \ - RB_ROTATE_LEFT(head, tmp, oright, field); \ - tmp =3D RB_LEFT(parent, field); \ - } else if (!RB_ISRED(RB_LEFT(tmp, field), field)) { \ - RB_COLOR(tmp, field) =3D RB_RED; \ - elm =3D parent; \ - parent =3D RB_PARENT(elm, field); \ + sib =3D RB_LEFT(elm, field); \ + if (RB_RED_RT(sib, field)) { \ + RB_ROTATE_LEFT(head, sib, tmp, field); \ + sib =3D tmp; \ + } else if (!RB_RED_LF(sib, field)) { \ + RB_FLIP_LF(elm, field); \ + elm =3D par; \ continue; \ } \ - if (RB_ISRED(RB_LEFT(tmp, field), field)) \ - RB_COLOR(RB_LEFT(tmp, field), field) =3D RB_BLACK; \ - RB_COLOR(tmp, field) =3D RB_COLOR(parent, field); \ - RB_COLOR(parent, field) =3D RB_BLACK; \ - RB_ROTATE_RIGHT(head, parent, tmp, field); \ - elm =3D RB_ROOT(head); \ + if (RB_RED_LF(sib, field)) \ + RB_FLIP_LF(sib, field); \ + RB_ROTATE_RIGHT(head, elm, sib, field); \ + RB_FLIP_RT(sib, field); \ break; \ } \ - } while (!RB_ISRED(elm, field) && parent !=3D NULL); \ - RB_COLOR(elm, field) =3D RB_BLACK; \ + } while (!red_par); \ + if (par !=3D NULL && red_par) { \ + if (left_child) \ + RB_FLIP_LF(par, field); \ + else \ + RB_FLIP_RT(par, field); \ + } \ } =20 #define RB_GENERATE_REMOVE(name, type, field, attr) \ @@ -550,12 +547,11 @@ attr struct type * \ name##_RB_REMOVE(struct name *head, struct type *elm) \ { \ struct type *child, *old, *parent, *parent_old, *right; \ - int color; \ + RB_BOOL old_red, red; \ \ old =3D elm; \ parent_old =3D parent =3D RB_PARENT(elm, field); \ right =3D RB_RIGHT(elm, field); \ - color =3D RB_COLOR(elm, field); \ if (RB_LEFT(elm, field) =3D=3D NULL) \ elm =3D child =3D right; \ else if (right =3D=3D NULL) \ @@ -563,7 +559,8 @@ name##_RB_REMOVE(struct name *head, struct type *elm)= \ else { \ if ((child =3D RB_LEFT(right, field)) =3D=3D NULL) { \ child =3D RB_RIGHT(right, field); \ - RB_RIGHT(old, field) =3D child; \ + red =3D RB_RED_RT(old, field); \ + RB_RT(old, field) =3D child; \ parent =3D elm =3D right; \ } else { \ do \ @@ -571,23 +568,31 @@ name##_RB_REMOVE(struct name *head, struct type *el= m) \ while ((child =3D RB_LEFT(elm, field)) !=3D NULL); \ child =3D RB_RIGHT(elm, field); \ parent =3D RB_PARENT(elm, field); \ - RB_LEFT(parent, field) =3D child; \ + red =3D RB_RED_LF(parent, field); \ + RB_LF(parent, field) =3D child; \ RB_PARENT(RB_RIGHT(old, field), field) =3D elm; \ } \ RB_PARENT(RB_LEFT(old, field), field) =3D elm; \ - color =3D RB_COLOR(elm, field); \ elm->field =3D old->field; \ } \ - if (parent_old =3D=3D NULL) \ + if (parent_old =3D=3D NULL) { \ RB_ROOT(head) =3D elm; \ - else if (RB_LEFT(parent_old, field) =3D=3D old) \ - RB_LEFT(parent_old, field) =3D elm; \ - else \ - RB_RIGHT(parent_old, field) =3D elm; \ - if (child !=3D NULL) { \ + old_red =3D RB_FALSE; \ + } else if (RB_LEFT(parent_old, field) =3D=3D old) { \ + old_red =3D RB_RED_LF(parent_old, field); \ + RB_LF(parent_old, field) =3D elm; \ + if (old_red && parent !=3D parent_old) \ + RB_FLIP_LF(parent_old, field); \ + } else { \ + old_red =3D RB_RED_RT(parent_old, field); \ + RB_RT(parent_old, field) =3D elm; \ + if (old_red && parent !=3D parent_old) \ + RB_FLIP_RT(parent_old, field); \ + } \ + if (child !=3D NULL) \ RB_PARENT(child, field) =3D parent; \ - RB_COLOR(child, field) =3D RB_BLACK; \ - } else if (color !=3D RB_RED && parent !=3D NULL) \ + else if (parent !=3D NULL && \ + (parent !=3D parent_old ? !red : !old_red)) \ name##_RB_REMOVE_COLOR(head, parent); \ while (parent !=3D NULL) { \ RB_AUGMENT(parent); \ @@ -615,14 +620,14 @@ name##_RB_INSERT(struct name *head, struct type *el= m) \ else \ return (tmp); \ } \ - RB_SET(elm, parent, field); \ - if (parent !=3D NULL) { \ - if (comp < 0) \ - RB_LEFT(parent, field) =3D elm; \ - else \ - RB_RIGHT(parent, field) =3D elm; \ - } else \ + RB_PARENT(elm, field) =3D parent; \ + RB_LF(elm, field) =3D RB_RT(elm, field) =3D NULL; \ + if (parent =3D=3D NULL) \ RB_ROOT(head) =3D elm; \ + else if (comp < 0) \ + RB_LF(parent, field) =3D elm; \ + else \ + RB_RT(parent, field) =3D elm; \ name##_RB_INSERT_COLOR(head, elm); \ while (elm !=3D NULL) { \ RB_AUGMENT(elm); \ --=20 2.26.2