This fixes build failure on i586, even though we never visit this code in i586 binary: http://cr.openjdk.java.net/~shade/shenandoah/build/masm-matrix-ptr/webrev.01/ In x86_64, imulptr/addptr alias to the same imulq/addq we have now. Testing: hotspot_gc_shenandoah Thanks, -Aleksey