From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from nikam.ms.mff.cuni.cz (nikam.ms.mff.cuni.cz [195.113.20.16]) by sourceware.org (Postfix) with ESMTPS id CF8C7385E02E for ; Tue, 14 Jun 2022 11:37:58 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org CF8C7385E02E Received: by nikam.ms.mff.cuni.cz (Postfix, from userid 16202) id 573D7289AB6; Tue, 14 Jun 2022 13:37:57 +0200 (CEST) Date: Tue, 14 Jun 2022 13:37:57 +0200 From: Jan Hubicka To: "Kewen.Lin" Cc: GCC Patches , Richard Sandiford , Segher Boessenkool Subject: Re: [PATCH] predict: Adjust optimize_function_for_size_p [PR105818] Message-ID: References: <23b4998b-bbe6-b052-d7f5-5304ee0f46a3@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <23b4998b-bbe6-b052-d7f5-5304ee0f46a3@linux.ibm.com> X-Spam-Status: No, score=-11.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, GIT_PATCH_0, KAM_SHORT, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, 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: Tue, 14 Jun 2022 11:38:01 -0000 > Hi, > > Function optimize_function_for_size_p returns OPTIMIZE_SIZE_NO > if func->decl is not null but no cgraph node is available for it. > As PR105818 shows, this could give unexpected result. For the > case in PR105818, when parsing bar decl in function foo, the cfun > is a function structure for foo, for which there is none cgraph > node, so it returns OPTIMIZE_SIZE_NO. But it's incorrect since > the context is to optimize for size, the flag optimize_size is > true. > > The patch is to make optimize_function_for_size_p to check > optimize_size as what it does when func->decl is unavailable. > > One regression failure got exposed on aarch64-linux-gnu: > > PASS->FAIL: gcc.dg/guality/pr54693-2.c -Os \ > -DPREVENT_OPTIMIZATION line 21 x == 10 - i > > The difference comes from the macro LOGICAL_OP_NON_SHORT_CIRCUIT > used in function fold_range_test during c parsing, it uses > optimize_function_for_speed_p which is equal to the invertion > of optimize_function_for_size_p. At that time cfun->decl is valid > but no cgraph node for it, w/o this patch function > optimize_function_for_speed_p returns true eventually, while it > returns false with this patch. Since the command line option -Os > is specified, there is no reason to interpret it as "for speed". > I think this failure is expected and adjust the test case > accordingly. > > Is it ok for trunk? > > BR, > Kewen > ----- > > PR target/105818 > > gcc/ChangeLog: > > * predict.cc (optimize_function_for_size_p): Check optimize_size when > func->decl is valid but its cgraph node is unavailable. > > gcc/testsuite/ChangeLog: > > * gcc.target/powerpc/pr105818.c: New test. > * gcc.dg/guality/pr54693-2.c: Adjust for aarch64. > --- > gcc/predict.cc | 2 +- > gcc/testsuite/gcc.dg/guality/pr54693-2.c | 2 +- > gcc/testsuite/gcc.target/powerpc/pr105818.c | 9 +++++++++ > 3 files changed, 11 insertions(+), 2 deletions(-) > create mode 100644 gcc/testsuite/gcc.target/powerpc/pr105818.c > > diff --git a/gcc/predict.cc b/gcc/predict.cc > index 5734e4c8516..6c60a973236 100644 > --- a/gcc/predict.cc > +++ b/gcc/predict.cc > @@ -268,7 +268,7 @@ optimize_function_for_size_p (struct function *fun) > cgraph_node *n = cgraph_node::get (fun->decl); > if (n) > return n->optimize_for_size_p (); > - return OPTIMIZE_SIZE_NO; > + return optimize_size ? OPTIMIZE_SIZE_MAX : OPTIMIZE_SIZE_NO; We could also do (opt_for_fn (cfun->decl, optimize_size) that is probably better since one can change optimize_size with optimization attribute. However I think in most cases we check for optimize_size early I think we are doing something wrong, since at that time htere is no profile available. Why exactly PR105818 hits the flag change issue? Honza > } > > /* Return true if function FUN should always be optimized for speed. */ > diff --git a/gcc/testsuite/gcc.dg/guality/pr54693-2.c b/gcc/testsuite/gcc.dg/guality/pr54693-2.c > index 68aa6c63d71..14ca94ad37d 100644 > --- a/gcc/testsuite/gcc.dg/guality/pr54693-2.c > +++ b/gcc/testsuite/gcc.dg/guality/pr54693-2.c > @@ -17,7 +17,7 @@ foo (int x, int y, int z) > int i = 0; > while (x > 3 && y > 3 && z > 3) > { /* { dg-final { gdb-test .+2 "i" "v + 1" } } */ > - /* { dg-final { gdb-test .+1 "x" "10 - i" } } */ > + /* { dg-final { gdb-test .+1 "x" "10 - i" { xfail { aarch64*-*-* && { any-opts "-Os" } } } } } */ > bar (i); /* { dg-final { gdb-test . "y" "20 - 2 * i" } } */ > /* { dg-final { gdb-test .-1 "z" "30 - 3 * i" { xfail { aarch64*-*-* && { any-opts "-fno-fat-lto-objects" "-Os" } } } } } */ > i++, x--, y -= 2, z -= 3; > diff --git a/gcc/testsuite/gcc.target/powerpc/pr105818.c b/gcc/testsuite/gcc.target/powerpc/pr105818.c > new file mode 100644 > index 00000000000..18781edbf9e > --- /dev/null > +++ b/gcc/testsuite/gcc.target/powerpc/pr105818.c > @@ -0,0 +1,9 @@ > +/* { dg-options "-Os -fno-tree-vectorize" } */ > + > +#pragma GCC optimize "-fno-tree-vectorize" > + > +void > +foo (void) > +{ > + void bar (void); > +} > -- > 2.27.0