mps br/vmem: simple-chunk-return:

arenavm.c -- move chunk-return into new function "VMCompact".
 (also, in VMArenaFinish, null out arena->primary in VMArenaFinish, so it is not left dangling).

 arena.c, arenavm.c, mpm.h, mpmst.h, mpmtypes.h:
 arena->class->compact: ArenaCompact, ArenaTrivCompact, VMCompact

 trace.c -- traceReclaim calls ArenaCompact!

Copied from Perforce
 Change: 170095
 ServerID: perforce.ravenbrook.com

1 files changed, 2 insertions, 0 deletions

diff --git a/mps/code/trace.c b/mps/code/trace.c
index b4b17c11b49..5cffa818009 100644
--- a/mps/code/trace.c
+++ b/mps/code/trace.c
@@ -813,6 +813,8 @@ static void traceReclaim(Trace trace)
     PoolTraceEnd(pool, trace);
   }
 
+  ArenaCompact(arena, trace);  /* let arenavm drop chunks */
+
   TracePostMessage(trace);  /* trace end */
   /* Immediately pre-allocate messages for next time; failure is okay */
   (void)TraceIdMessagesCreate(arena, trace->ti);