__getcontextx_size
ctx = malloc(__getcontextx_size());
ctx = malloc(__getcontextx_size());
ctx = malloc(__getcontextx_size());
ctx = malloc(__getcontextx_size());
DEFINE_UIFUNC(, int, __getcontextx_size, (void))
uc_len = __getcontextx_size();
uc_len = __getcontextx_size();
int __getcontextx_size(void);