https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83296
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |ASSIGNED
Last reconfirmed| |2017-12-07
Assignee|unassigned at gcc dot gnu.org |rguenth at gcc dot
gnu.org
Ever confirmed|0 |1
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Happens because:
/* Create an SSA var to hold the min/max result. If we're the only
things setting the target PHI, then we can clone the PHI
variable. Otherwise we must create a new one. */
result = PHI_RESULT (phi);
if (EDGE_COUNT (gimple_bb (phi)->preds) == 2)
result = duplicate_ssa_name (result, NULL);
else
result = make_ssa_name (TREE_TYPE (result));
/* Emit the statement to compute min/max. */
new_stmt = gimple_build_assign (result, minmax, arg0, arg1);
gsi = gsi_last_bb (cond_bb);
gsi_insert_before (&gsi, new_stmt, GSI_NEW_STMT);
replace_phi_edge_with_variable (cond_bb, e1, phi, result);
ok until here but then:
reset_flow_sensitive_info_in_bb (cond_bb);
added by r228341. I don't see immediately why we need that - it resets
flow-sensitive info in the BB of the conditional not in a block only
dominated by the true/false edge.
I have a patch.
