Subversion Repositories hf-risc

#include <sysdep.h>

#include <sys/asm.h>

#include <sys/ucontext.h>

#include <stdarg.h>

#include <assert.h>

void __makecontext (ucontext_t *ucp, void (*func) (void), int argc,

                    long a0, long a1, long a2, long a3, long a4, ...)

{

  extern void __start_context(void) attribute_hidden;

  long i, sp;

  assert(REG_NARGS == 8);

  /* Set up the stack. */

  sp = ((long)ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size) & ALMASK;

  /* Set up the register context.

     ra = s0 = 0, terminating the stack for backtracing purposes.

     s1 = the function we must call.

     s2 = the subsequent context to run.  */

  ucp->uc_mcontext.gregs[REG_RA] = 0;

  ucp->uc_mcontext.gregs[REG_S0 + 0] = 0;

  ucp->uc_mcontext.gregs[REG_S0 + 1] = (long)func;

  ucp->uc_mcontext.gregs[REG_S0 + 2] = (long)ucp->uc_link;

  ucp->uc_mcontext.gregs[REG_SP] = sp;

  ucp->uc_mcontext.gregs[REG_PC] = (long)&__start_context;

  /* Put args in a0-a7, then put any remaining args on the stack. */

  ucp->uc_mcontext.gregs[REG_A0 + 0] = a0;

  ucp->uc_mcontext.gregs[REG_A0 + 1] = a1;

  ucp->uc_mcontext.gregs[REG_A0 + 2] = a2;

  ucp->uc_mcontext.gregs[REG_A0 + 3] = a3;

  ucp->uc_mcontext.gregs[REG_A0 + 4] = a4;

  if (__builtin_expect (argc > 5, 0))

    {

      va_list vl;

      va_start(vl, a4);

      long reg_args = argc < REG_NARGS ? argc : REG_NARGS;

      sp = (sp - (argc - reg_args) * sizeof(long)) & ALMASK;

      for (i = 5; i < reg_args; i++)

        ucp->uc_mcontext.gregs[REG_A0 + i] = va_arg(vl, long);

      for (i = 0; i < argc - reg_args; i++)

        ((long*)sp)[i] = va_arg(vl, long);

      va_end(vl);

    }

}

weak_alias (__makecontext, makecontext)