8224580: Matcher can cause oop field/array element to be reloaded
Reviewed-by: neliasso, rkennke, dlong
--- a/src/hotspot/share/opto/matcher.cpp Wed Jun 05 12:02:01 2019 +0100
+++ b/src/hotspot/share/opto/matcher.cpp Tue May 21 09:08:01 2019 +0200
@@ -2066,6 +2066,12 @@
// Node is shared and has no reason to clone. Flag it as shared.
// This causes it to match into a register for the sharing.
set_shared(n); // Flag as shared and
+ if (n->is_DecodeNarrowPtr()) {
+ // Oop field/array element loads must be shared but since
+ // they are shared through a DecodeN they may appear to have
+ // a single use so force sharing here.
+ set_shared(n->in(1));
+ }
mstack.pop(); // remove node from stack
continue;
}
@@ -2098,13 +2104,6 @@
continue; // for(int i = ...)
}
- if( mop == Op_AddP && m->in(AddPNode::Base)->is_DecodeNarrowPtr()) {
- // Bases used in addresses must be shared but since
- // they are shared through a DecodeN they may appear
- // to have a single use so force sharing here.
- set_shared(m->in(AddPNode::Base)->in(1));
- }
-
// if 'n' and 'm' are part of a graph for BMI instruction, clone this node.
#ifdef X86
if (UseBMI1Instructions && is_bmi_pattern(n, m)) {