I introduced jmpb_if_possible and jccb_if_possible to macroAssembler_x86 in order to deal with increased offsets when ShenandoahStoreCheck is enabled. This patch fixes it so that it also works correctly with release build and under correct conditions. http://cr.openjdk.java.net/~rkennke/fix-jmp-if-possible/webrev.00/ Ok?