Commit efb6bc55a9 ("fwprop: Allow (subreg (mem)) simplifications")
introduced a check that was supposed to look at the propagated def's
number of uses. It uses insn_info::num_uses (), which in reality
returns the number of uses def's insn has. The whole change therefore
works only by accident.
Fix by looking at set_info's uses instead of insn_info's uses. This
requires passing around set_info instead of insn_info.
gcc/ChangeLog:
2021-03-02 Ilya Leoshkevich <iii@linux.ibm.com>
* fwprop.c (fwprop_propagation::fwprop_propagation): Look at
set_info's uses.
(try_fwprop_subst_note): Use set_info instead of insn_info.
(try_fwprop_subst_pattern): Likewise.
(try_fwprop_subst_notes): Likewise.
(try_fwprop_subst): Likewise.
(forward_propagate_subreg): Likewise.
(forward_propagate_and_simplify): Likewise.
(forward_propagate_into): Likewise.
* rtl-ssa/accesses.h (set_info::single_nondebug_use) New
method.
(set_info::single_nondebug_insn_use): Likewise.
(set_info::single_phi_use): Likewise.
* rtl-ssa/member-fns.inl (set_info::single_nondebug_use) New
method.
(set_info::single_nondebug_insn_use): Likewise.
(set_info::single_phi_use): Likewise.
gcc/testsuite/ChangeLog:
* gcc.target/s390/vector/long-double-asm-abi.c: New test.
b61461ac7f