#ifdef __STDC__
# define __CONCAT(x,y)  x ## y
# define __STRING(x)    #x
#else
# define __CONCAT(x,y)  x/**/y
# define __STRING(x)    "x"
#endif

#define SET_CPUVAR(off,reg) \
         mvhi    r25, hi(_C_LABEL(cpu_info_store)) ; \
         ori     r25, r25, lo(_C_LABEL(cpu_info_store)) ; \
         lw      reg, (r25+__CONCAT(CPU_INFO_,off))

or

.macro set_cpuvar off, reg
        mvhi    r25, hi(_C_LABEL(cpu_info_store))
        ori     r25, r25, lo(_C_LABEL(cpu_info_store))
        lw      \reg, (r25+__CONCAT(CPU_INFO_,\off))
.endm