8005956: C2: assert(!def_outside->member(r)) failed: Use of external LRG overlaps the same LRG defined in this block
Summary: Disable re-materialization of reaching definitions (which have live inputs) for phi nodes when spilling.
Reviewed-by: twisti, kvn
--- a/hotspot/src/share/vm/opto/reg_split.cpp Mon Jun 03 08:52:20 2013 +0200
+++ b/hotspot/src/share/vm/opto/reg_split.cpp Mon Jun 03 12:39:33 2013 -0700
@@ -51,6 +51,15 @@
static const char out_of_nodes[] = "out of nodes during split";
+static bool contains_no_live_range_input(const Node* def) {
+ for (uint i = 1; i < def->req(); ++i) {
+ if (def->in(i) != NULL && def->in_RegMask(i).is_NotEmpty()) {
+ return false;
+ }
+ }
+ return true;
+}
+
//------------------------------get_spillcopy_wide-----------------------------
// Get a SpillCopy node with wide-enough masks. Use the 'wide-mask', the
// wide ideal-register spill-mask if possible. If the 'wide-mask' does
@@ -1312,7 +1321,7 @@
Node *def = Reaches[pidx][slidx];
assert( def, "must have reaching def" );
// If input up/down sense and reg-pressure DISagree
- if( def->rematerialize() ) {
+ if (def->rematerialize() && contains_no_live_range_input(def)) {
// Place the rematerialized node above any MSCs created during
// phi node splitting. end_idx points at the insertion point
// so look at the node before it.