From c41884a09206be0e21cad7eea71b9754daa969d4 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Fri, 17 Apr 2020 10:33:27 +0200 Subject: [PATCH] Fix -fcompare-debug issue in delete_insn_and_edges [PR94618] delete_insn_and_edges calls purge_dead_edges whenever deleting the last insn in a bb, whatever it is. If it called it only for mandatory last insns in the basic block (that may not be followed by DEBUG_INSNs, dunno if that is control_flow_insn_p or something more complex), that wouldn't be a problem, but as it calls it on any last insn and can actually do something in the bb, if such an insn is followed by one more more DEBUG_INSNs and nothing else in the same bb, we don't call purge_dead_edges with -g and do call it with -g0. On the testcase, there are two reg-to-reg moves with REG_EH_REGION notes (previously memory accesses but simplified and yet not optimized), and the second is followed by DEBUG_INSNs; the second move is delete_insn_and_edges and after removing it, for -g0 purge_dead_edges removes the REG_EH_REGION from the now last insn in the bb (the first reg-to-reg move), while for -g it isn't called and things diverge from that quickly on. Fixed by calling purdge_dead_edges even if we remove the last real insn followed only by DEBUG_INSNs in the same bb. 2020-04-17 Jakub Jelinek PR rtl-optimization/94618 * cfgrtl.c (delete_insn_and_edges): Set purge not just when insn is the BB_END of its block, but also when it is only followed by DEBUG_INSNs in its block. * g++.dg/opt/pr94618.C: New test. --- gcc/ChangeLog | 5 +++++ gcc/cfgrtl.c | 18 ++++++++++++++---- gcc/testsuite/ChangeLog | 3 +++ gcc/testsuite/g++.dg/opt/pr94618.C | 25 +++++++++++++++++++++++++ 4 files changed, 47 insertions(+), 4 deletions(-) create mode 100644 gcc/testsuite/g++.dg/opt/pr94618.C diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 80b0534ba51..8bce0ea6146 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,10 @@ 2020-04-17 Jakub Jelinek + PR rtl-optimization/94618 + * cfgrtl.c (delete_insn_and_edges): Set purge not just when + insn is the BB_END of its block, but also when it is only followed + by DEBUG_INSNs in its block. + PR tree-optimization/94621 * tree-inline.c (remap_type_1): Don't dereference NULL TYPE_DOMAIN. Move id->adjust_array_error_bounds check first in the condition. diff --git a/gcc/cfgrtl.c b/gcc/cfgrtl.c index fb551e3efc0..e6ea687ef31 100644 --- a/gcc/cfgrtl.c +++ b/gcc/cfgrtl.c @@ -230,10 +230,20 @@ delete_insn_and_edges (rtx_insn *insn) { bool purge = false; - if (INSN_P (insn) - && BLOCK_FOR_INSN (insn) - && BB_END (BLOCK_FOR_INSN (insn)) == insn) - purge = true; + if (INSN_P (insn) && BLOCK_FOR_INSN (insn)) + { + basic_block bb = BLOCK_FOR_INSN (insn); + if (BB_END (bb) == insn) + purge = true; + else if (DEBUG_INSN_P (BB_END (bb))) + for (rtx_insn *dinsn = NEXT_INSN (insn); + DEBUG_INSN_P (dinsn); dinsn = NEXT_INSN (dinsn)) + if (BB_END (bb) == dinsn) + { + purge = true; + break; + } + } delete_insn (insn); if (purge) return purge_dead_edges (BLOCK_FOR_INSN (insn)); diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 64181e4e532..dd2cb04916f 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,5 +1,8 @@ 2020-04-17 Jakub Jelinek + PR rtl-optimization/94618 + * g++.dg/opt/pr94618.C: New test. + PR tree-optimization/94621 * gcc.c-torture/compile/pr94621.c: New test. diff --git a/gcc/testsuite/g++.dg/opt/pr94618.C b/gcc/testsuite/g++.dg/opt/pr94618.C new file mode 100644 index 00000000000..e6a81d2c5ab --- /dev/null +++ b/gcc/testsuite/g++.dg/opt/pr94618.C @@ -0,0 +1,25 @@ +// PR rtl-optimization/94618 +// { dg-do compile { target c++11 } } +// { dg-options "-O2 -fnon-call-exceptions -fcompare-debug" } + +struct S +{ + int a, b, c; + int foo () noexcept { return a; } + int bar () noexcept { return b; } + void baz (int); + void qux () { if (c) for (int x = foo (); x != bar (); ) baz (x); } +}; + +struct T +{ + S s; + void foo (); +}; + +void +T::foo () +{ + s.qux (); + s.qux (); +} -- 2.30.2