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author | Jakub Jelinek <jakub@redhat.com> | 2020-04-17 10:33:27 +0200 |
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committer | Jakub Jelinek <jakub@redhat.com> | 2020-04-17 10:33:27 +0200 |
commit | c41884a09206be0e21cad7eea71b9754daa969d4 (patch) | |
tree | 9a197fc01c6e4fa97c82c78963dc71548fbe50e0 /gcc/cfgrtl.c | |
parent | c58cb6ac6891886b7aa01c440ac71a5e7cbcba97 (diff) | |
download | gcc-c41884a09206be0e21cad7eea71b9754daa969d4.zip gcc-c41884a09206be0e21cad7eea71b9754daa969d4.tar.gz gcc-c41884a09206be0e21cad7eea71b9754daa969d4.tar.bz2 |
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 <jakub@redhat.com>
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.
Diffstat (limited to 'gcc/cfgrtl.c')
-rw-r--r-- | gcc/cfgrtl.c | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/gcc/cfgrtl.c b/gcc/cfgrtl.c index fb551e3..e6ea687 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)); |