diff -r fb0e525008c5 -r dcf7e9d7b506 src/arch/arm/isa/insts/macromem.isa
--- a/src/arch/arm/isa/insts/macromem.isa	Fri May 13 17:29:27 2011 -0500
+++ b/src/arch/arm/isa/insts/macromem.isa	Tue May 17 11:46:28 2011 -0700
@@ -541,6 +541,9 @@
             for (unsigned i = 0; i < %(sRegs)d; i++) {
                 destRegs.elements[i] = sourceRegs[i].elements[lane];
             }
+            for (unsigned i = %(sRegs)d; i < %(dRegs)d * perDReg; ++i) {
+                destRegs.elements[i] = 0;
+            }
 
             %(unloadRegs)s
             ''' % { "sRegs" : sRegs, "dRegs" : dRegs,