diff -r c76c13577460 -r b2cb497dec28 src/share/vm/opto/library_call.cpp
--- a/src/share/vm/opto/library_call.cpp	Thu May 26 16:39:34 2011 -0700
+++ b/src/share/vm/opto/library_call.cpp	Fri May 27 12:47:48 2011 -0700
@@ -5225,15 +5225,16 @@
 
   // Look at the alignment of the starting offsets.
   int abase = arrayOopDesc::base_offset_in_bytes(basic_elem_type);
-  const intptr_t BIG_NEG = -128;
-  assert(BIG_NEG + 2*abase < 0, "neg enough");
-
-  intptr_t src_off  = abase + ((intptr_t) find_int_con(src_offset, -1)  << scale);
-  intptr_t dest_off = abase + ((intptr_t) find_int_con(dest_offset, -1) << scale);
-  if (src_off < 0 || dest_off < 0)
+
+  intptr_t src_off_con  = (intptr_t) find_int_con(src_offset, -1);
+  intptr_t dest_off_con = (intptr_t) find_int_con(dest_offset, -1);
+  if (src_off_con < 0 || dest_off_con < 0)
     // At present, we can only understand constants.
     return false;
 
+  intptr_t src_off  = abase + (src_off_con  << scale);
+  intptr_t dest_off = abase + (dest_off_con << scale);
+
   if (((src_off | dest_off) & (BytesPerLong-1)) != 0) {
     // Non-aligned; too bad.
     // One more chance:  Pick off an initial 32-bit word.