From de702b3a1f3f7c1179023a9f340e4f2a5a9f3bce Mon Sep 17 00:00:00 2001
From: kvn <unknown>
Date: Mon, 31 Mar 2008 18:37:36 -0700
Subject: [PATCH] 6682236: C2 hits ideal nodes limit during IGVN optimization
 with EA Summary: missing check in LoadNode::Ideal() causes infinite
 generation of a value Phi. Reviewed-by: jrose, never

---
 src/share/vm/opto/memnode.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/share/vm/opto/memnode.cpp b/src/share/vm/opto/memnode.cpp
index d3027cec7..df47ccb0e 100644
--- a/src/share/vm/opto/memnode.cpp
+++ b/src/share/vm/opto/memnode.cpp
@@ -1122,6 +1122,12 @@ Node *LoadNode::Ideal(PhaseGVN *phase, bool can_reshape) {
         }
         // Split through Phi (see original code in loopopts.cpp).
         assert(phase->C->have_alias_type(addr_t), "instance should have alias type");
+
+        // Do nothing here if Identity will find a value
+        // (to avoid infinite chain of value phis generation).
+        if ( !phase->eqv(this, this->Identity(phase)) )
+          return NULL;
+
         const Type* this_type = this->bottom_type();
         int this_index  = phase->C->get_alias_index(addr_t);
         int this_offset = addr_t->offset();
-- 
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