From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by sourceware.org (Postfix) with ESMTPS id A1B8C383E058 for ; Wed, 31 Aug 2022 13:19:43 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org A1B8C383E058 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id 738B822197 for ; Wed, 31 Aug 2022 13:19:42 +0000 (UTC) Received: from wotan.suse.de (wotan.suse.de [10.160.0.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id 6D7CC2C141 for ; Wed, 31 Aug 2022 13:19:42 +0000 (UTC) Date: Wed, 31 Aug 2022 13:19:42 +0000 (UTC) From: Richard Biener To: gcc-patches@gcc.gnu.org Subject: [PATCH] tree-optimization/90994 - fix uninit diagnostics with EH User-Agent: Alpine 2.22 (LSU 394 2020-01-19) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Spam-Status: No, score=-10.6 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, MISSING_MID, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) 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: , X-List-Received-Date: Wed, 31 Aug 2022 13:19:45 -0000 Message-ID: <20220831131942.8IpDA1KANDXnctre0q31y6xGXqXh0wIsz-3Gy17s154@z> r12-3640-g94c12ffac234b2 sneaked in a hack to avoid the diagnostic for the testcase in PR90994 which sees non-call EH control flow confusing predicate analysis. The following patch instead adjusts the existing code handling EH to handle non-calls and do what I think was intented. Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed. PR tree-optimization/90994 * gimple-predicate-analysis.cc (): Ignore exceptional control flow and skip the edge for the purpose of predicate generation also for non-calls. * g++.dg/torture/pr90994.C: New testcase. --- gcc/gimple-predicate-analysis.cc | 13 +++++---- gcc/testsuite/g++.dg/torture/pr90994.C | 40 ++++++++++++++++++++++++++ 2 files changed, 48 insertions(+), 5 deletions(-) create mode 100644 gcc/testsuite/g++.dg/torture/pr90994.C diff --git a/gcc/gimple-predicate-analysis.cc b/gcc/gimple-predicate-analysis.cc index 49500b77832..58eade433dc 100644 --- a/gcc/gimple-predicate-analysis.cc +++ b/gcc/gimple-predicate-analysis.cc @@ -41,6 +41,7 @@ #include "calls.h" #include "value-query.h" #include "cfganal.h" +#include "tree-eh.h" #include "gimple-predicate-analysis.h" @@ -1709,9 +1710,6 @@ predicate::init_from_control_deps (const vec *dep_chains, } /* Get the conditional controlling the bb exit edge. */ gimple *cond_stmt = gsi_stmt (gsi); - if (is_gimple_call (cond_stmt) && EDGE_COUNT (e->src->succs) >= 2) - /* Ignore EH edge. Can add assertion on the other edge's flag. */ - continue; /* Skip this edge if it is bypassing an abort - when the condition is not satisfied we are neither reaching the definition nor the use so it isn't meaningful. Note if @@ -1819,10 +1817,15 @@ predicate::init_from_control_deps (const vec *dep_chains, has_valid_pred = true; } } + else if (stmt_can_throw_internal (cfun, cond_stmt) + && !(e->flags & EDGE_EH)) + /* Ignore the exceptional control flow and proceed as if + E were a fallthru without a controlling predicate for + both the USE (valid) and DEF (questionable) case. */ + has_valid_pred = true; else { - /* Disabled. See PR 90994. - has_valid_pred = false; */ + has_valid_pred = false; break; } } diff --git a/gcc/testsuite/g++.dg/torture/pr90994.C b/gcc/testsuite/g++.dg/torture/pr90994.C new file mode 100644 index 00000000000..8feb36f2361 --- /dev/null +++ b/gcc/testsuite/g++.dg/torture/pr90994.C @@ -0,0 +1,40 @@ +// { dg-do compile } +// { dg-additional-options "-fnon-call-exceptions -Wuninitialized" } + +extern void printval(unsigned char v); + +inline int readbyte(unsigned char *__restrict presult, + unsigned char volatile *ptr) +{ + unsigned char v; + try { + v = *ptr; + } catch (...) { + return -1; + } + *presult = v; + return 0; +} + +int incorrectWarning(unsigned char volatile *ptr) +{ + int error; + unsigned char first; + unsigned char second; + + error = readbyte(&first, ptr); + asm("\n\n\n\n\n" : : "X" (error != 0)); + if (error != 0) + goto err; + + error = readbyte(&second, ptr); + if (error != 0) + goto err; + + printval(first); // { dg-bogus "uninitialized" } + printval(second); + return 0; + +err: + return error; +} -- 2.35.3