From patchwork Wed Dec 1 14:27:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Siddhesh Poyarekar X-Patchwork-Id: 48355 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id E54F63858006 for ; Wed, 1 Dec 2021 14:28:38 +0000 (GMT) X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from olivedrab.birch.relay.mailchannels.net (olivedrab.birch.relay.mailchannels.net [23.83.209.135]) by sourceware.org (Postfix) with ESMTPS id B134E385840D for ; Wed, 1 Dec 2021 14:28:20 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org B134E385840D Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=gotplt.org Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gotplt.org X-Sender-Id: dreamhost|x-authsender|siddhesh@gotplt.org Received: from relay.mailchannels.net (localhost [127.0.0.1]) by relay.mailchannels.net (Postfix) with ESMTP id C71AB8818F6; Wed, 1 Dec 2021 14:28:18 +0000 (UTC) Received: from pdx1-sub0-mail-a307.dreamhost.com (unknown [127.0.0.6]) (Authenticated sender: dreamhost) by relay.mailchannels.net (Postfix) with ESMTPA id 549E388222C; Wed, 1 Dec 2021 14:28:17 +0000 (UTC) X-Sender-Id: dreamhost|x-authsender|siddhesh@gotplt.org Received: from pdx1-sub0-mail-a307.dreamhost.com (pop.dreamhost.com [64.90.62.162]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384) by 100.114.196.229 (trex/6.4.3); Wed, 01 Dec 2021 14:28:18 +0000 X-MC-Relay: Neutral X-MailChannels-SenderId: dreamhost|x-authsender|siddhesh@gotplt.org X-MailChannels-Auth-Id: dreamhost X-Oafish-Power: 0988537a1dfa68ca_1638368898624_3065580470 X-MC-Loop-Signature: 1638368898624:3287245388 X-MC-Ingress-Time: 1638368898624 Received: from rhbox.intra.reserved-bit.com (unknown [1.186.123.150]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: siddhesh@gotplt.org) by pdx1-sub0-mail-a307.dreamhost.com (Postfix) with ESMTPSA id 4J41f732Zbz3L; Wed, 1 Dec 2021 06:28:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=gotplt.org; s=gotplt.org; t=1638368897; bh=uu/5iinxT1pJpqrzmgrm2aDSlYM=; h=From:To:Cc:Subject:Date:Content-Transfer-Encoding; b=DRNEUH20d14cM3bGnk7k5QWZvXsnTzVDSqmW8afSLZoVnBvxl5s96z1Arf/l6JnbE gbnv+hWlbuPpXW/35aPBJvGrWPRV9IybcG6uBdatCawqGTQaWZl1oDM9pI3ADZvHm7 16Ms55KEpRCLlopCnKpUaIDxMLaWNW/BgkNj5Cxc= From: Siddhesh Poyarekar To: gcc-patches@gcc.gnu.org Subject: [PATCH v4 4/6] tree-object-size: Handle function parameters Date: Wed, 1 Dec 2021 19:57:55 +0530 Message-Id: <20211201142757.4086840-5-siddhesh@gotplt.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211201142757.4086840-1-siddhesh@gotplt.org> References: <20211109190137.1107736-1-siddhesh@gotplt.org> <20211201142757.4086840-1-siddhesh@gotplt.org> MIME-Version: 1.0 X-Spam-Status: No, score=-3039.6 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, RCVD_IN_SBL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: jakub@redhat.com Errors-To: gcc-patches-bounces+patchwork=sourceware.org@gcc.gnu.org Sender: "Gcc-patches" Handle hints provided by __attribute__ ((access (...))) to compute dynamic sizes for objects. gcc/ChangeLog: * tree-object-size.c: Include tree-dfa.h. (parm_object_size): New function. (collect_object_sizes_for): Call it. gcc/testsuite/ChangeLog: * gcc.dg/builtin-dynamic-object-size-0.c (test_parmsz_simple): New function. (main): Call it. Signed-off-by: Siddhesh Poyarekar --- .../gcc.dg/builtin-dynamic-object-size-0.c | 11 ++++ gcc/tree-object-size.c | 50 ++++++++++++++++++- 2 files changed, 60 insertions(+), 1 deletion(-) diff --git a/gcc/testsuite/gcc.dg/builtin-dynamic-object-size-0.c b/gcc/testsuite/gcc.dg/builtin-dynamic-object-size-0.c index ddedf6a49bd..ce0f4eb17f3 100644 --- a/gcc/testsuite/gcc.dg/builtin-dynamic-object-size-0.c +++ b/gcc/testsuite/gcc.dg/builtin-dynamic-object-size-0.c @@ -46,6 +46,14 @@ test_deploop (size_t sz, size_t cond) return __builtin_dynamic_object_size (bin, 0); } +size_t +__attribute__ ((access (__read_write__, 1, 2))) +__attribute__ ((noinline)) +test_parmsz_simple (void *obj, size_t sz) +{ + return __builtin_dynamic_object_size (obj, 0); +} + unsigned nfails = 0; #define FAIL() ({ \ @@ -64,6 +72,9 @@ main (int argc, char **argv) FAIL (); if (test_deploop (128, 129) != 32) FAIL (); + if (test_parmsz_simple (argv[0], __builtin_strlen (argv[0]) + 1) + != __builtin_strlen (argv[0]) + 1) + FAIL (); if (nfails > 0) __builtin_abort (); diff --git a/gcc/tree-object-size.c b/gcc/tree-object-size.c index dd6c90efebf..bbc708f8ade 100644 --- a/gcc/tree-object-size.c +++ b/gcc/tree-object-size.c @@ -32,6 +32,7 @@ along with GCC; see the file COPYING3. If not see #include "gimple-fold.h" #include "gimple-iterator.h" #include "tree-cfg.h" +#include "tree-dfa.h" #include "stringpool.h" #include "attribs.h" #include "builtins.h" @@ -1449,6 +1450,53 @@ cond_expr_object_size (struct object_size_info *osi, tree var, gimple *stmt) return reexamine; } +/* Find size of an object passed as a parameter to the function. */ + +static void +parm_object_size (struct object_size_info *osi, tree var) +{ + int object_size_type = osi->object_size_type; + tree parm = SSA_NAME_VAR (var); + + if (!(object_size_type & OST_DYNAMIC) || !POINTER_TYPE_P (TREE_TYPE (parm))) + expr_object_size (osi, var, parm); + + /* Look for access attribute. */ + rdwr_map rdwr_idx; + + tree fndecl = cfun->decl; + const attr_access *access = get_parm_access (rdwr_idx, parm, fndecl); + tree typesize = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (parm))); + tree sz = NULL_TREE; + + if (access && access->sizarg != UINT_MAX) + { + tree fnargs = DECL_ARGUMENTS (fndecl); + tree arg = NULL_TREE; + unsigned argpos = 0; + + /* Walk through the parameters to pick the size parameter and safely + scale it by the type size. */ + for (arg = fnargs; argpos != access->sizarg && arg; + arg = TREE_CHAIN (arg), ++argpos); + + if (arg != NULL_TREE && INTEGRAL_TYPE_P (TREE_TYPE (arg))) + { + sz = get_or_create_ssa_default_def (cfun, arg); + if (sz != NULL_TREE) + { + sz = fold_convert (sizetype, sz); + if (typesize) + sz = size_binop (MULT_EXPR, sz, typesize); + } + } + } + if (!sz) + sz = size_unknown (object_size_type); + + object_sizes_set (osi, SSA_NAME_VERSION (var), sz, sz); +} + /* Compute an object size expression for VAR, which is the result of a PHI node. */ @@ -1606,7 +1654,7 @@ collect_object_sizes_for (struct object_size_info *osi, tree var) case GIMPLE_NOP: if (SSA_NAME_VAR (var) && TREE_CODE (SSA_NAME_VAR (var)) == PARM_DECL) - expr_object_size (osi, var, SSA_NAME_VAR (var)); + parm_object_size (osi, var); else /* Uninitialized SSA names point nowhere. */ unknown_object_size (osi, var);