runtime/src/ARM/RTThread.m3


Copyright (C) 1994, Digital Equipment Corp.

UNSAFE MODULE RTThread;

IMPORT Word, Usignal;

CONST
  SP_pos = 13;  (* THESE DON'T AGREE WITH Csetjmp.jmp_buf !!! *)
  FP_pos = 15;

PROCEDURE SP (READONLY s: State): ADDRESS =
  BEGIN
    RETURN LOOPHOLE (s [SP_pos], ADDRESS);
  END SP;
--------------------------------------------------------- thread stacks ---

PROCEDURE NewStack (size: INTEGER;  VAR(*OUT*)s: Stack) =
  BEGIN
    s.words := NEW (StackSpace, size);
    s.first := ADR (s.words[0]);
    s.last  := s.first + size * ADRSIZE (s.words[0]);
  END NewStack;

PROCEDURE DisposeStack (VAR s: Stack) =
  BEGIN
    DISPOSE (s.words);
    s.words := NIL;
    s.first := NIL;
    s.last  := NIL;
  END DisposeStack;

PROCEDURE FlushStackCache () =
  VAR d: State;
  BEGIN
    Transfer (d, d);
  END FlushStackCache;
-------------------------------------------------- modifying the models ---

PROCEDURE UpdateStateForNewSP (VAR s: State; offset: INTEGER) =
  BEGIN
    INC (s [SP_pos], offset);
    INC (s [FP_pos], offset);
  END UpdateStateForNewSP;

PROCEDURE UpdateFrameForNewSP (<*UNUSED*> a: ADDRESS;
                               <*UNUSED*> offset: INTEGER) =
  BEGIN
  END UpdateFrameForNewSP;
------------------------------------ manipulating the SIGVTALRM handler ---

PROCEDURE setup_sigvtalrm (handler: Usignal.SignalHandler) =
  VAR sv, osv: Usignal.struct_sigvec;  i: INTEGER;
  BEGIN
    sv.sv_handler := handler;
    sv.sv_mask    := Usignal.empty_sv_mask;
    sv.sv_flags   := 0;
    i := Usignal.sigvec (Usignal.SIGVTALRM, sv, osv);
    <* ASSERT i = 0 *>
  END setup_sigvtalrm;

PROCEDURE allow_sigvtalrm () =
  VAR i : Word.T;
  BEGIN
    i := Usignal.sigsetmask (0);
    i := Word.And (i, Word.Not (Usignal.sigmask (Usignal.SIGVTALRM)));
    EVAL Usignal.sigsetmask (i);
  END allow_sigvtalrm;

PROCEDURE disallow_sigvtalrm () =
  VAR i : Word.T;
  BEGIN
    i := Usignal.sigsetmask (0);
    i := Word.Or (i, Usignal.sigmask (Usignal.SIGVTALRM));
    EVAL Usignal.sigsetmask (i);
  END disallow_sigvtalrm;

BEGIN
END RTThread.

interface Usignal is in: