https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86489
--- Comment #3 from kugan at gcc dot gnu.org ---
(In reply to Richard Biener from comment #2)
> gimple *phi = SSA_NAME_DEF_STMT (b_11);
> if (gimple_code (phi) != GIMPLE_PHI
> || (gimple_assign_lhs (and_stmt)
> != gimple_phi_arg_def (phi, loop_latch_edge (loop)->dest_idx)))
> return false;
>
> this may fail if the PHI in question is not the correct one in which case
> it may not have the argument at the latch dest_idx. Try first verifying
> that the loop latch destination is indeed gimple_bb (phi).
yes, thanks for spotting. I am testing the following patch:
diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c
index f6fa2f7..fbdf838 100644
--- a/gcc/tree-ssa-loop-niter.c
+++ b/gcc/tree-ssa-loop-niter.c
@@ -2555,6 +2555,7 @@ number_of_iterations_popcount (loop_p loop, edge exit,
... = PHI <b_5(2), b_6(3)>. */
gimple *phi = SSA_NAME_DEF_STMT (b_11);
if (gimple_code (phi) != GIMPLE_PHI
+ || (gimple_bb (phi) != loop_latch_edge (loop)->dest)
|| (gimple_assign_lhs (and_stmt)
!= gimple_phi_arg_def (phi, loop_latch_edge (loop)->dest_idx)))
return false;
is checking that there is argument at the latch dest_idx (argument count of
PHI) is still necessary?
