8335220: C2: Missing check for Opaque4 node in EscapeAnalysis

Reviewed-by: vlivanov
Backport-of: 9d986a013d01a5bcc0942bcc490258038291c22c
This commit is contained in:
Vladimir Kozlov 2024-06-29 02:20:07 +00:00
parent 32ed61572c
commit 87a29629e3

View File

@ -574,18 +574,23 @@ bool ConnectionGraph::can_reduce_check_users(Node* n, uint nesting) const {
// CmpP/N used by the If controlling the cast.
if (use->in(0)->is_IfTrue() || use->in(0)->is_IfFalse()) {
Node* iff = use->in(0)->in(0);
if (iff->Opcode() == Op_If && iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp()) {
// We may have Opaque4 node between If and Bool nodes.
// Bail out in such case - we need to preserve Opaque4 for correct
// processing predicates after loop opts.
bool can_reduce = (iff->Opcode() == Op_If) && iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp();
if (can_reduce) {
Node* iff_cmp = iff->in(1)->in(1);
int opc = iff_cmp->Opcode();
if ((opc == Op_CmpP || opc == Op_CmpN) && !can_reduce_cmp(n, iff_cmp)) {
can_reduce = (opc == Op_CmpP || opc == Op_CmpN) && can_reduce_cmp(n, iff_cmp);
}
if (!can_reduce) {
#ifndef PRODUCT
if (TraceReduceAllocationMerges) {
tty->print_cr("Can NOT reduce Phi %d on invocation %d. CastPP %d doesn't have simple control.", n->_idx, _invocation, use->_idx);
n->dump(5);
}
#endif
return false;
if (TraceReduceAllocationMerges) {
tty->print_cr("Can NOT reduce Phi %d on invocation %d. CastPP %d doesn't have simple control.", n->_idx, _invocation, use->_idx);
n->dump(5);
}
#endif
return false;
}
}
}
@ -651,7 +656,12 @@ Node* ConnectionGraph::specialize_cmp(Node* base, Node* curr_ctrl) {
if (curr_ctrl == nullptr || curr_ctrl->is_Region()) {
con = _igvn->zerocon(t->basic_type());
} else {
Node* curr_cmp = curr_ctrl->in(0)->in(1)->in(1); // true/false -> if -> bool -> cmp
// can_reduce_check_users() verified graph: true/false -> if -> bool -> cmp
assert(curr_ctrl->in(0)->Opcode() == Op_If, "unexpected node %s", curr_ctrl->in(0)->Name());
Node* bol = curr_ctrl->in(0)->in(1);
assert(bol->is_Bool(), "unexpected node %s", bol->Name());
Node* curr_cmp = bol->in(1);
assert(curr_cmp->Opcode() == Op_CmpP || curr_cmp->Opcode() == Op_CmpN, "unexpected node %s", curr_cmp->Name());
con = curr_cmp->in(1)->is_Con() ? curr_cmp->in(1) : curr_cmp->in(2);
}