7010665: Misplaced membar in C1 implementation of Unsafe.get/putXXX
Summary: Modify membars to match regular volatile variable handling
Reviewed-by: iveresov, kvn, never
--- a/hotspot/src/share/vm/c1/c1_LIRGenerator.cpp Fri Jan 07 13:59:48 2011 -0800
+++ b/hotspot/src/share/vm/c1/c1_LIRGenerator.cpp Sun Jan 09 17:16:16 2011 -0500
@@ -1990,9 +1990,8 @@
LIR_Opr reg = reg = rlock_result(x, x->basic_type());
+ get_Object_unsafe(reg, src.result(), off.result(), type, x->is_volatile());
if (x->is_volatile() && os::is_MP()) __ membar_acquire();
- get_Object_unsafe(reg, src.result(), off.result(), type, x->is_volatile());
- if (x->is_volatile() && os::is_MP()) __ membar();
}
@@ -2014,6 +2013,7 @@
if (x->is_volatile() && os::is_MP()) __ membar_release();
put_Object_unsafe(src.result(), off.result(), data.result(), type, x->is_volatile());
+ if (x->is_volatile() && os::is_MP()) __ membar();
}