m3core/src/runtime/common/RTAllocStats.i3

 Copyright (C) 1995, Digital Equipment Corporation         
 All rights reserved.                                      
 See the file COPYRIGHT for a full description.            
                                                           
| Last modified on Thu May  4 16:25:48 PDT 1995 by kalsow  
|      modified on Mon Mar  6 23:49:50 PST 1995 by detlefs 


INTERFACE RTAllocStats;

 This interface controls the collection of per-call-site
   allocation statistics.  This interface is only useful on
   platforms with a stack walker (ie. DS3100 & ALPHA_OSF),
   on all other platforms these routines are no-ops.


   NOTE: The implementation of this interface uses the spare
         fields of REF headers.



FROM RT0 IMPORT Typecode;

VAR siteDepth := 3;

 The number of procedure frames included in a site. 

PROCEDURE EnableTrace (tc: Typecode);

 Begin recording allocation statistics for type tc.  It is a
   checked runtime error to pass an improper typecode or one that
   corresponds to an untraced type. 

PROCEDURE NSites (tc: Typecode): INTEGER;

 Returns the number of sites recorded for type tc.  If sites are
   not being recorded for tc, returns -1. 

PROCEDURE GetSiteText (tc: Typecode; site, depth: CARDINAL): TEXT;

 If sites are being traced for type tc, site is a valid tag for
   the type, and depth is less than the siteDepth when the site
   was captured, return a description of the procedure frame corresponding
   to the captured PC.  Otherwise, return NIL. 

END RTAllocStats.