fusl/arch/arm/bits/user.h

typedef struct user_fpregs {
  struct fp_reg {
    unsigned sign1 : 1;
    unsigned unused : 15;
    unsigned sign2 : 1;
    unsigned exponent : 14;
    unsigned j : 1;
    unsigned mantissa1 : 31;
    unsigned mantissa0 : 32;
  } fpregs[8];
  unsigned fpsr : 32;
  unsigned fpcr : 32;
  unsigned char ftype[8];
  unsigned int init_flag;
} elf_fpregset_t;

struct user_regs {
  unsigned long uregs[18];
};
#define ELF_NGREG 18
typedef unsigned long elf_greg_t, elf_gregset_t[ELF_NGREG];

struct user {
  struct user_regs regs;
  int u_fpvalid;
  unsigned long u_tsize, u_dsize, u_ssize;
  unsigned long start_code, start_stack;
  long signal;
  int reserved;
  struct user_regs* u_ar0;
  unsigned long magic;
  char u_comm[32];
  int u_debugreg[8];
  struct user_fpregs u_fp;
  struct user_fpregs* u_fp0;
};