_CONST
#define MMU_PAGEOFFSET _CONST(MMU_PAGESIZE-1) /* assembler lameness */
subq $_CONST(_MUL(XMM_SIZE, nreg)), %rsp; \
addq $_CONST(_MUL(XMM_SIZE, nreg)), %rsp
subl $_CONST(_MUL(XMM_SIZE, nreg) + XMM_ALIGN), %esp; \
addl $_CONST(_MUL(XMM_SIZE, nreg) + XMM_ALIGN), %esp;
#define _BITNOT(const) ~_CONST(const)
#define _MUL(a, b) _CONST(a * b)