Copyright (C) 1994, Digital Equipment Corporation.       
 All rights reserved.                                     
 See the file COPYRIGHT for a full description.           
 Last modified on Tue May  2 11:42:57 PDT 1995 by kalsow  

This interface defines platform (machine + OS) dependent types and constants.


IMPORT Csetjmp;
IMPORT Usignal;
FROM Upthread IMPORT pthread_t;
--------------------------------------------------------- thread state ---

TBD: remove userthread and gcvm support, which includes much of the below

  State = Csetjmp.jmp_buf;
  (* The machine state is saved in a "State".  This is opaque to the client. *)

<*EXTERNAL "_setjmp" *>
PROCEDURE SaveState (VAR s: State): INTEGER;
Capture the currently running thread's state
------------------------------------------------------------------ heap ---

The heap page size is machine-dependent, since it might depend on the architecture's VM page size (if VM is TRUE). Otherwise, 8192 bytes is a reasonable page size. The page size must be a power of two.

  BytesPerHeapPage    = 8192;        (* bytes per page *)
  LogBytesPerHeapPage = 13;
  AdrPerHeapPage      = 8192;        (* addresses per page *)
  LogAdrPerHeapPage   = 13;
--------------------------------------------------------- thread stacks ---

PointerAlignment = BYTESIZE(INTEGER);
  (* The C compiler allocates all pointers on 'PointerAlignment'-byte
     boundaries.  The garbage collector scans thread stacks, but only
     looks at these possible pointer locations.  Setting this value
     smaller than is needed will only make your system run slower.
     Setting it too large will cause the collector to collect storage
     that is not free. *)
----------------------------------------------- exception stack walking --- The FrameInfo type must minimally include fields named pc and sp.

Has_stack_walker = FALSE;
  (* Indicates whether this platform supports the stack walking functions
     defined in the "RTStack" interface. *)

TYPE FrameInfo = RECORD pc, sp: ADDRESS END;

  SIG_SUSPEND = Usignal.NSIG-1; (* SIGRTMAX *)
  SuspendThread: PROCEDURE(t: pthread_t): BOOLEAN = NIL;
  RestartThread: PROCEDURE(t: pthread_t) = NIL;
  GetState: PROCEDURE(t: pthread_t; VAR state: ThreadState): ADDRESS = NIL;
  SaveRegsInStack: PROCEDURE(): ADDRESS = NIL;

TYPE ThreadState = RECORD END;

END RTMachine.

interface Csetjmp is in:

interface Usignal is in:

interface Upthread is in: