From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1666) id B18F438582A7; Wed, 31 Aug 2022 13:20:50 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B18F438582A7 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1661952050; bh=JzGlrMc4ZtzamZtw2bccB5DgfGS6B1DGcM6tfo/1SLs=; h=From:To:Subject:Date:From; b=vPKVnWwkoRdFWkENrgxQ1kLmy1z1Ot9H4NMVMRsErg14JSPkG9LoWAJH9N2da0HcJ yQk8meZfeqEZrLaSVWc2SaPyYoS2VAXTWRV9pqFamu9Tn9+n3K6ZPEHF6P/n2yHPc/ 1xkrxe6uRCPMRCo+QUMA/kAj4xmb538/gExtBvyU= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Richard Biener To: gcc-cvs@gcc.gnu.org Subject: [gcc r13-2310] tree-optimization/90994 - fix uninit diagnostics with EH X-Act-Checkin: gcc X-Git-Author: Richard Biener X-Git-Refname: refs/heads/master X-Git-Oldrev: 25dd2768afdb8fad7b11d511eb5f739958f9870d X-Git-Newrev: 88f29a8aa82f2788baf2f9865940d4c83012c580 Message-Id: <20220831132050.B18F438582A7@sourceware.org> Date: Wed, 31 Aug 2022 13:20:50 +0000 (GMT) List-Id: https://gcc.gnu.org/g:88f29a8aa82f2788baf2f9865940d4c83012c580 commit r13-2310-g88f29a8aa82f2788baf2f9865940d4c83012c580 Author: Richard Biener Date: Wed Aug 31 14:04:46 2022 +0200 tree-optimization/90994 - fix uninit diagnostics with EH 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. PR tree-optimization/90994 * gimple-predicate-analysis.cc (predicate::init_from_control_deps): 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. Diff: --- gcc/gimple-predicate-analysis.cc | 13 ++++++----- gcc/testsuite/g++.dg/torture/pr90994.C | 40 ++++++++++++++++++++++++++++++++++ 2 files changed, 48 insertions(+), 5 deletions(-) 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; +}