| Message ID | ZS7yiPmkNmgUNDrh@arm.com |
|---|---|
| State | New |
| Headers | show |
| Series | aarch64: Add new load/store pair fusion pass | expand |
Alex Coplan <alex.coplan@arm.com> writes: > In the case that !insn->is_debug_insn () && next->is_debug_insn (), this > function was missing an update of the prev pointer on the first nondebug > insn following the sequence of debug insns starting at next. > > This can lead to corruption of the insn chain, in that we end up with: > > insn->next_any_insn ()->prev_any_insn () != insn > > in this case. This patch fixes that. > > Bootstrapped/regtested as a series on aarch64-linux-gnu, OK for trunk? > > gcc/ChangeLog: > > * rtl-ssa/insns.cc (function_info::add_insn_after): Ensure we > update the prev pointer on the following nondebug insn in the > case that !insn->is_debug_insn () && next->is_debug_insn (). OK, thanks. Richard > --- > gcc/rtl-ssa/insns.cc | 14 +++++++++++--- > 1 file changed, 11 insertions(+), 3 deletions(-) > > diff --git a/gcc/rtl-ssa/insns.cc b/gcc/rtl-ssa/insns.cc > index a0c2fec2b70..f970375d906 100644 > --- a/gcc/rtl-ssa/insns.cc > +++ b/gcc/rtl-ssa/insns.cc > @@ -291,9 +291,17 @@ function_info::add_insn_after (insn_info *insn, insn_info *after) > first->set_last_debug_insn (insn); > } > else // !insn->is_debug_insn () && next->is_debug_insn () > - // At present we don't (need to) support inserting a nondebug > - // instruction between two existing debug instructions. > - gcc_assert (!after->is_debug_insn ()); > + { > + // At present we don't (need to) support inserting a nondebug > + // instruction between two existing debug instructions. > + gcc_assert (!after->is_debug_insn ()); > + > + // Find the next nondebug insn and update its previous pointer > + // to point to INSN. > + auto next_nondebug = next->last_debug_insn ()->next_any_insn (); > + gcc_checking_assert (!next_nondebug->is_debug_insn ()); > + next_nondebug->set_prev_sametype_insn (insn); > + } > > // If AFTER and NEXT are separated by at least two points, we can > // use a unique point number for INSN. Otherwise INSN will have
diff --git a/gcc/rtl-ssa/insns.cc b/gcc/rtl-ssa/insns.cc index a0c2fec2b70..f970375d906 100644 --- a/gcc/rtl-ssa/insns.cc +++ b/gcc/rtl-ssa/insns.cc @@ -291,9 +291,17 @@ function_info::add_insn_after (insn_info *insn, insn_info *after) first->set_last_debug_insn (insn); } else // !insn->is_debug_insn () && next->is_debug_insn () - // At present we don't (need to) support inserting a nondebug - // instruction between two existing debug instructions. - gcc_assert (!after->is_debug_insn ()); + { + // At present we don't (need to) support inserting a nondebug + // instruction between two existing debug instructions. + gcc_assert (!after->is_debug_insn ()); + + // Find the next nondebug insn and update its previous pointer + // to point to INSN. + auto next_nondebug = next->last_debug_insn ()->next_any_insn (); + gcc_checking_assert (!next_nondebug->is_debug_insn ()); + next_nondebug->set_prev_sametype_insn (insn); + } // If AFTER and NEXT are separated by at least two points, we can // use a unique point number for INSN. Otherwise INSN will have