https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68522
Yuri Rumyantsev <ysrumyan at gmail dot com> changed:
What |Removed |Added
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CC| |ysrumyan at gmail dot com
--- Comment #5 from Yuri Rumyantsev <ysrumyan at gmail dot com> ---
I did deeper investigation of 435.gromacs miscomparison and found out that
1. It is caused by precision lost, i.e. this is not bug in split-paths phase.
2. This is caused by fmadd-sub instructions only (reproduced on avx2 with
fma-support), i.e. with -fno-fma option bench is passed.
3. I found the first guilty routine split-paths for which leads to
miscomparison: (fsettle) which is an ordinary fp-routine with big exit bb which
is replicated. I assume that restriction on size of exit bb to be duplicated
must be introduced to avoid useless code size growth. So you can close it after
adding correspondent parameter-limit.
