From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl1-x62d.google.com (mail-pl1-x62d.google.com [IPv6:2607:f8b0:4864:20::62d]) by sourceware.org (Postfix) with ESMTPS id 6F9E33858D28 for ; Tue, 2 May 2023 22:04:44 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 6F9E33858D28 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-pl1-x62d.google.com with SMTP id d9443c01a7336-1ab13da70a3so8896885ad.1 for ; Tue, 02 May 2023 15:04:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1683065083; x=1685657083; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=G/tToci/2pSvWtzEp5GBxuT9kgADHQNBJpha2WzcEeI=; b=U72rKRttyL+xG8J0r7D7eZLYwC1TcX3EffUgdVdVvbmsBhEJB7U1oWH0GEBC52qTbP uFvS892tEfig2wb0cgFA6d3h/NF3VQ/ydxPUxGJlA0QaINE0JjQAflVasHHT8Q23zSVw 6f9Cz2HqhME86oaPUgN9jQHicebdFzZsHPNwlhCWhPX4IeW/IPNoavU82LjF4HdcGygm EtENy7Gsi87imhYQ+YArYeiuTxJah2RCkzjZf3ha06vJ4Wn9gptn8M/WCc65Jx9lQW2n gEmfrbuucPtA97UuhqGShgmCHAkTayeQL8v8USn2hWwva4HsA5CNrJQxuMcXIp3NUOgs SkVA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683065083; x=1685657083; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=G/tToci/2pSvWtzEp5GBxuT9kgADHQNBJpha2WzcEeI=; b=h9Qy1eHJ+KzqIRr9sIQKbVxB8TiToXvVGNBe3imTYbJUNoeyEBXbfvsNZFrB0faBxd Q8GuYICmfzgTOhSdFv5t2T2s/f3w6tVe9dJGPYKFlntQnToMTE5Cctodq/mZOzjc8YSp R7DBBOhImcsoGdQGlLsd+s0nYKCz2/UmndsXKP+Db5Z0AR8YcF8RW3f5YHU7VQ2IjHSG FD/U8FK/l5PUDJOZIPhoeEHUSdDLTwZN5vxh1vrPeAI3HPgJnqHb1prvXB5PX/i4DZXP PDWgJec8tvc4xJGfz5AJjdhzee4aZXNh0TYqyzxHpbOBaGsMJNQonxJ3HUYVoZz+iOGW wIeg== X-Gm-Message-State: AC+VfDxBViGqd+tLCYRbifgVlLDzdXUpTa5Kw3qnJ7oXyiF+Wk2Uyu6S dQCV+sqX1PKMZsQAtr4GTS5hYyr9uwdDbDig1pY= X-Google-Smtp-Source: ACHHUZ6hOTLtRawmzOQiX7v1igYtp23Ik851B86PNcL9alMNlj+FxOMIlQB+Am7M0iYCzFFDlD3mWWUXgg2N3S57S2o= X-Received: by 2002:a17:90a:f415:b0:24e:1144:ef52 with SMTP id ch21-20020a17090af41500b0024e1144ef52mr6133004pjb.11.1683065082712; Tue, 02 May 2023 15:04:42 -0700 (PDT) MIME-Version: 1.0 References: <20230430211356.762030-1-apinski@marvell.com> In-Reply-To: From: Andrew Pinski Date: Tue, 2 May 2023 15:04:30 -0700 Message-ID: Subject: Re: [PATCH] PHIOPT: Improve replace_phi_edge_with_variable for diamond shapped bb To: Richard Biener Cc: Andrew Pinski , gcc-patches@gcc.gnu.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-7.4 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM,GIT_PATCH_0,RCVD_IN_DNSWL_NONE,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 List-Id: On Tue, May 2, 2023 at 5:26=E2=80=AFAM Richard Biener via Gcc-patches wrote: > > On Sun, Apr 30, 2023 at 11:14=E2=80=AFPM Andrew Pinski via Gcc-patches > wrote: > > > > While looking at differences between what minmax_replacement > > and match_simplify_replacement does. I noticed that they sometimes > > chose different edges to remove. I decided we should be able to do > > better and be able to remove both empty basic blocks in the > > case of match_simplify_replacement as that moves the statements. > > > > This also updates the testcases as now match_simplify_replacement > > will remove the unused MIN/MAX_EXPR and they were checking for > > those. > > > > OK? Bootstrapped and tested on x86_64-linux-gnu with no regressions. > > > > gcc/ChangeLog: > > > > * tree-ssa-phiopt.cc (copy_phi_args): New function. > > (replace_phi_edge_with_variable): Handle diamond form bb > > with forwarder only empty blocks better. > > > > gcc/testsuite/ChangeLog: > > > > * gcc.dg/tree-ssa/minmax-15.c: Update test. > > * gcc.dg/tree-ssa/minmax-16.c: Update test. > > * gcc.dg/tree-ssa/minmax-3.c: Update test. > > * gcc.dg/tree-ssa/minmax-4.c: Update test. > > * gcc.dg/tree-ssa/minmax-5.c: Update test. > > * gcc.dg/tree-ssa/minmax-8.c: Update test. > > --- > > gcc/testsuite/gcc.dg/tree-ssa/minmax-15.c | 3 +- > > gcc/testsuite/gcc.dg/tree-ssa/minmax-16.c | 9 ++-- > > gcc/testsuite/gcc.dg/tree-ssa/minmax-3.c | 2 +- > > gcc/testsuite/gcc.dg/tree-ssa/minmax-4.c | 2 +- > > gcc/testsuite/gcc.dg/tree-ssa/minmax-5.c | 2 +- > > gcc/testsuite/gcc.dg/tree-ssa/minmax-8.c | 2 +- > > gcc/tree-ssa-phiopt.cc | 51 ++++++++++++++++++++++- > > 7 files changed, 59 insertions(+), 12 deletions(-) > > > > diff --git a/gcc/testsuite/gcc.dg/tree-ssa/minmax-15.c b/gcc/testsuite/= gcc.dg/tree-ssa/minmax-15.c > > index 8a39871c938..6731f91e6c3 100644 > > --- a/gcc/testsuite/gcc.dg/tree-ssa/minmax-15.c > > +++ b/gcc/testsuite/gcc.dg/tree-ssa/minmax-15.c > > @@ -30,5 +30,6 @@ main (void) > > return 0; > > } > > > > -/* { dg-final { scan-tree-dump-times "MIN_EXPR" 3 "phiopt1" } } */ > > +/* There should only be two MIN_EXPR left, the 3rd one was removed. */ > > +/* { dg-final { scan-tree-dump-times "MIN_EXPR" 2 "phiopt1" } } */ > > /* { dg-final { scan-tree-dump-times "MAX_EXPR" 0 "phiopt1" } } */ > > diff --git a/gcc/testsuite/gcc.dg/tree-ssa/minmax-16.c b/gcc/testsuite/= gcc.dg/tree-ssa/minmax-16.c > > index 623b12b3f74..094364e6424 100644 > > --- a/gcc/testsuite/gcc.dg/tree-ssa/minmax-16.c > > +++ b/gcc/testsuite/gcc.dg/tree-ssa/minmax-16.c > > @@ -25,11 +25,8 @@ main (void) > > return 0; > > } > > > > -/* After phiopt1, there really should be only 3 MIN_EXPR in the IR (in= cluding debug statements). > > - But the way phiopt does not cleanup the CFG all the time, the PHI m= ight still reference the > > - alternative bb's moved statement. > > - Note in the end, we do dce the statement and other debug statements= to end up with only 2 MIN_EXPR. > > - So check that too. */ > > -/* { dg-final { scan-tree-dump-times "MIN_EXPR" 4 "phiopt1" } } */ > > +/* After phiopt1, will be only 2 MIN_EXPR in the IR (including debug s= tatements). */ > > +/* xk will only have the final result so the extra debug info does not= change anything. */ > > +/* { dg-final { scan-tree-dump-times "MIN_EXPR" 2 "phiopt1" } } */ > > /* { dg-final { scan-tree-dump-times "MIN_EXPR" 2 "optimized" } } */ > > /* { dg-final { scan-tree-dump-times "MAX_EXPR" 0 "phiopt1" } } */ > > diff --git a/gcc/testsuite/gcc.dg/tree-ssa/minmax-3.c b/gcc/testsuite/g= cc.dg/tree-ssa/minmax-3.c > > index 2af10776346..521afe3e4d9 100644 > > --- a/gcc/testsuite/gcc.dg/tree-ssa/minmax-3.c > > +++ b/gcc/testsuite/gcc.dg/tree-ssa/minmax-3.c > > @@ -25,5 +25,5 @@ main (void) > > return 0; > > } > > > > -/* { dg-final { scan-tree-dump-times "MIN_EXPR" 3 "phiopt1" } } */ > > +/* { dg-final { scan-tree-dump-times "MIN_EXPR" 2 "phiopt1" } } */ > > /* { dg-final { scan-tree-dump-times "MAX_EXPR" 0 "phiopt1" } } */ > > diff --git a/gcc/testsuite/gcc.dg/tree-ssa/minmax-4.c b/gcc/testsuite/g= cc.dg/tree-ssa/minmax-4.c > > index 973f39bfed3..49e27185b5e 100644 > > --- a/gcc/testsuite/gcc.dg/tree-ssa/minmax-4.c > > +++ b/gcc/testsuite/gcc.dg/tree-ssa/minmax-4.c > > @@ -26,4 +26,4 @@ main (void) > > } > > > > /* { dg-final { scan-tree-dump-times "MIN_EXPR" 0 "phiopt1" } } */ > > -/* { dg-final { scan-tree-dump-times "MAX_EXPR" 3 "phiopt1" } } */ > > +/* { dg-final { scan-tree-dump-times "MAX_EXPR" 2 "phiopt1" } } */ > > diff --git a/gcc/testsuite/gcc.dg/tree-ssa/minmax-5.c b/gcc/testsuite/g= cc.dg/tree-ssa/minmax-5.c > > index 34e4e720511..194c881cc98 100644 > > --- a/gcc/testsuite/gcc.dg/tree-ssa/minmax-5.c > > +++ b/gcc/testsuite/gcc.dg/tree-ssa/minmax-5.c > > @@ -25,5 +25,5 @@ main (void) > > return 0; > > } > > > > -/* { dg-final { scan-tree-dump-times "MIN_EXPR" 2 "phiopt1" } } */ > > +/* { dg-final { scan-tree-dump-times "MIN_EXPR" 1 "phiopt1" } } */ > > /* { dg-final { scan-tree-dump-times "MAX_EXPR" 1 "phiopt1" } } */ > > diff --git a/gcc/testsuite/gcc.dg/tree-ssa/minmax-8.c b/gcc/testsuite/g= cc.dg/tree-ssa/minmax-8.c > > index 0160e573fef..d5cb53145ea 100644 > > --- a/gcc/testsuite/gcc.dg/tree-ssa/minmax-8.c > > +++ b/gcc/testsuite/gcc.dg/tree-ssa/minmax-8.c > > @@ -26,4 +26,4 @@ main (void) > > } > > > > /* { dg-final { scan-tree-dump-times "MIN_EXPR" 1 "phiopt1" } } */ > > -/* { dg-final { scan-tree-dump-times "MAX_EXPR" 2 "phiopt1" } } */ > > +/* { dg-final { scan-tree-dump-times "MAX_EXPR" 1 "phiopt1" } } */ > > diff --git a/gcc/tree-ssa-phiopt.cc b/gcc/tree-ssa-phiopt.cc > > index 65b3deea34a..311423efeb5 100644 > > --- a/gcc/tree-ssa-phiopt.cc > > +++ b/gcc/tree-ssa-phiopt.cc > > @@ -82,6 +82,25 @@ single_non_singleton_phi_for_edges (gimple_seq seq, = edge e0, edge e1) > > return phi; > > } > > > > +/* For each PHI in BB, copy the argument associated with SRC_E to TGT_= E. */ > > + > > +static void > > +copy_phi_args (basic_block bb, edge src_e, edge tgt_e) > > +{ > > + gphi_iterator gsi; > > + int src_indx =3D src_e->dest_idx; > > + > > + for (gsi =3D gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) > > + { > > + gphi *phi =3D gsi.phi (); > > + tree def =3D gimple_phi_arg_def (phi, src_indx); > > + location_t locus =3D gimple_phi_arg_location (phi, src_indx); > > + > > + add_phi_arg (phi, def, tgt_e, locus); > > + } > > +} > > Doesn't flush_pending_stmts (tgt_e) do this? No, In fact the above code is very similar to the code from remove_forwarder_block in tree-cfgcleanup.cc (I copied it and changed it from copy_phi_args in tree-ssa-threadupdate.cc though as I don't need a mapping). Let me factor out the code from remove_forwarder_block and put it in some common spot and then use that; it will be the same logic even. Thanks, Andrew > > > + > > + > > /* Replace PHI node element whose edge is E in block BB with variable = NEW. > > Remove the edge from COND_BLOCK which does not lead to BB (COND_BLO= CK > > is known to have two edges, one of which must reach BB). */ > > @@ -94,6 +113,7 @@ replace_phi_edge_with_variable (basic_block cond_blo= ck, > > basic_block bb =3D gimple_bb (phi); > > gimple_stmt_iterator gsi; > > tree phi_result =3D PHI_RESULT (phi); > > + bool deleteboth =3D false; > > > > /* Duplicate range info if they are the only things setting the targ= et PHI. > > This is needed as later on, the new_tree will be replacing > > @@ -137,7 +157,14 @@ replace_phi_edge_with_variable (basic_block cond_b= lock, > > keep_edge =3D EDGE_SUCC (cond_block, 1); > > } > > else if ((keep_edge =3D find_edge (cond_block, e->src))) > > - ; > > + { > > + basic_block bb1 =3D EDGE_SUCC (cond_block, 0)->dest; > > + basic_block bb2 =3D EDGE_SUCC (cond_block, 1)->dest; > > + if (single_pred_p (bb1) && single_pred_p (bb2) > > + && single_succ_p (bb1) && single_succ_p (bb2) > > + && empty_block_p (bb1) && empty_block_p (bb2)) > > + deleteboth =3D true; > > + } > > else > > gcc_unreachable (); > > > > @@ -148,6 +175,28 @@ replace_phi_edge_with_variable (basic_block cond_b= lock, > > e->probability =3D profile_probability::always (); > > delete_basic_block (edge_to_remove->dest); > > > > + /* Eliminate the COND_EXPR at the end of COND_BLOCK. */ > > + gsi =3D gsi_last_bb (cond_block); > > + gsi_remove (&gsi, true); > > + } > > + else if (deleteboth) > > + { > > + basic_block bb1 =3D EDGE_SUCC (cond_block, 0)->dest; > > + basic_block bb2 =3D EDGE_SUCC (cond_block, 1)->dest; > > + > > + edge newedge =3D redirect_edge_and_branch (keep_edge, bb); > > + /* no new edge should be the same. */ > > + gcc_assert (newedge =3D=3D keep_edge); > > + keep_edge->flags |=3D EDGE_FALLTHRU; > > + keep_edge->flags &=3D ~(EDGE_TRUE_VALUE | EDGE_FALSE_VALUE); > > + keep_edge->probability =3D profile_probability::always (); > > + /* Copy the edge's phi entry from the old one */ > > + copy_phi_args(bb, e, keep_edge); > > + > > + /* Delete the old 2 empty basic blocks */ > > + delete_basic_block (bb1); > > + delete_basic_block (bb2); > > + > > /* Eliminate the COND_EXPR at the end of COND_BLOCK. */ > > gsi =3D gsi_last_bb (cond_block); > > gsi_remove (&gsi, true); > > -- > > 2.31.1 > >