From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1666) id 7F6A63858D39; Wed, 3 Nov 2021 14:00:21 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 7F6A63858D39 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 r12-4865] tree-optimization/102970 - remap cliques when translating over backedges X-Act-Checkin: gcc X-Git-Author: Richard Biener X-Git-Refname: refs/heads/master X-Git-Oldrev: 67b0d47e20e655c0dd53a76ea88aab60fafb2059 X-Git-Newrev: 1967fd8f2197f2b0334ab0fbc26abc3d9efe56c9 Message-Id: <20211103140021.7F6A63858D39@sourceware.org> Date: Wed, 3 Nov 2021 14:00:21 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 03 Nov 2021 14:00:21 -0000 https://gcc.gnu.org/g:1967fd8f2197f2b0334ab0fbc26abc3d9efe56c9 commit r12-4865-g1967fd8f2197f2b0334ab0fbc26abc3d9efe56c9 Author: Richard Biener Date: Wed Nov 3 13:26:48 2021 +0100 tree-optimization/102970 - remap cliques when translating over backedges The following makes sure to remap (or rather drop for simplicity) dependence info encoded in MR_DEPENDENCE_CLIQUE when PRE PHI translation translates a reference over a backedge since that ends up interleaving two different loop iterations which boils down to two different inline copies. 2021-11-03 Richard Biener PR tree-optimization/102970 * tree-ssa-pre.c (phi_translate_1): Drop clique and base when translating a MEM_REF over a backedge. * g++.dg/opt/pr102970.C: New testcase. Diff: --- gcc/testsuite/g++.dg/opt/pr102970.C | 60 +++++++++++++++++++++++++++++++++++++ gcc/tree-ssa-pre.c | 15 ++++++++++ 2 files changed, 75 insertions(+) diff --git a/gcc/testsuite/g++.dg/opt/pr102970.C b/gcc/testsuite/g++.dg/opt/pr102970.C new file mode 100644 index 00000000000..cf5b0ed70b4 --- /dev/null +++ b/gcc/testsuite/g++.dg/opt/pr102970.C @@ -0,0 +1,60 @@ +// { dg-do run } +// { dg-require-effective-target c++11 } +// { dg-options "-O2 -funroll-loops -fno-tree-vectorize" } + +#include +#include +#include + +struct box { + box(int xmin, int xmax, int ymin, int ymax) noexcept + : m_xmin(xmin), + m_xmax(xmax), + m_ymin(ymin), + m_ymax(ymax) { + } + + box(box const & o) noexcept + : m_xmin(o.m_xmin), + m_xmax(o.m_xmax), + m_ymin(o.m_ymin), + m_ymax(o.m_ymax) { } + + int m_xmin; + int m_xmax; + int m_ymin; + int m_ymax; +}; + + +int main() { + std::vector vRects{ // requires 18 elements + { 900, 11, 22, 33 }, + { 901, 11, 22, 33 }, + { 902, 11, 22, 33 }, + { 903, 11, 22, 33 }, + { 704, 11, 22, 33 }, + { 705, 11, 22, 33 }, + { 706, 11, 22, 33 }, + { 707, 11, 22, 33 }, + { 808, 11, 22, 33 }, + { 809, 11, 22, 33 }, + { 810, 11, 22, 33 }, + { 811, 11, 22, 33 }, + { 812, 11, 22, 33 }, + { 813, 11, 22, 33 }, + { 814, 11, 22, 33 }, + { 815, 11, 22, 33 }, + { 816, 11, 22, 33 }, + { 817, 11, 22, 33 }, + { 818, 11, 22, 33 }, + }; + + std::stable_sort(vRects.begin(), vRects.end(), + [](auto const &r1, auto const &r2) -> bool + { + if (r2.m_xmax==0||r2.m_ymin==0||r2.m_ymax==0){__builtin_abort();} + return r1.m_xmin < r2.m_xmin; + }); + return 0; +} diff --git a/gcc/tree-ssa-pre.c b/gcc/tree-ssa-pre.c index 1cc1aae694f..dc55d868cc1 100644 --- a/gcc/tree-ssa-pre.c +++ b/gcc/tree-ssa-pre.c @@ -1588,6 +1588,21 @@ phi_translate_1 (bitmap_set_t dest, newoperands.release (); return NULL; } + /* When we translate a MEM_REF across a backedge and we have + restrict info that's not from our functions parameters + we have to remap it since we now may deal with a different + instance where the dependence info is no longer valid. + See PR102970. Note instead of keeping a remapping table + per backedge we simply throw away restrict info. */ + if ((newop.opcode == MEM_REF + || newop.opcode == TARGET_MEM_REF) + && newop.clique > 1 + && (e->flags & EDGE_DFS_BACK)) + { + newop.clique = 0; + newop.base = 0; + changed = true; + } if (!changed) continue; if (!newoperands.exists ())