b8aaa2c367
i386-only section, and fix a comment about the amd64 kernel trapframe not having stackregs. tf_rsp doesn't need decoding on amd64, but had an old clone of i386 code to do this in 1 place, and since the amd64 kernel trapframe does have stackregs, the result was an off-by-16 error for %rsp in an error message.