Fix review comments from <https://info.ravenbrook.com/mail/2013/05/28/22-21-11/0/>:

* Rename RangeOverlap to RangesOverlap.
* MVFF shouldn't assume that CBSInsert and CBSDelete can't fail.
* Remove unused function mps_mvff_stat.
* Don't call range methods in RangeCheck.
* RangeInit can't fail, so return void.

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 Change: 182297
 ServerID: perforce.ravenbrook.com

mps/code/poolmv2.c

@@ -605,7 +605,7 @@ static Bool MVTDeleteOverlapping(ABQDisposition *dispositionReturn,
   oldRange = element;
   newRange = closureP;
 
-  if (RangeOverlap(oldRange, newRange)) {
+  if (RangesOverlap(oldRange, newRange)) {
     *dispositionReturn = ABQDispositionDELETE;
   } else {
     *dispositionReturn = ABQDispositionKEEP;

mps/code/poolmvff.c

@@ -80,7 +80,7 @@ typedef MVFFDebugStruct *MVFFDebug;
  *
  * Updates MVFF counters for additional free space.  Returns maximally
  * coalesced range containing given range.  Does not attempt to free
- * segments (see MVFFFreeSegs).  Cannot(!) fail.
+ * segments (see MVFFFreeSegs).
  */
 static void MVFFAddToFreeList(Addr *baseIO, Addr *limitIO, MVFF mvff) {
   Res res;
@@ -94,6 +94,10 @@ static void MVFFAddToFreeList(Addr *baseIO, Addr *limitIO, MVFF mvff) {
   AVER(limit > base);
 
   res = CBSInsert(baseIO, limitIO, CBSOfMVFF(mvff), base, limit);
+  if (ResIsAllocFailure(res))
+    /* CBS ran out of memory for splay nodes: lose freed range. */
+    return;
+
   AVER(res == ResOK);
   mvff->free += AddrOffset(base, limit);
 
@@ -138,6 +142,10 @@ static void MVFFFreeSegs(MVFF mvff, Addr base, Addr limit)
     if (segBase >= base) { /* segment starts in range */
       Addr oldBase, oldLimit;
       res = CBSDelete(&oldBase, &oldLimit, CBSOfMVFF(mvff), segBase, segLimit);
+      if (ResIsAllocFailure(res))
+        /* CBS ran out of memory for splay nodes: can't delete. */
+        return;
+
       AVER(res == ResOK);
       AVER(oldBase <= segBase);
       AVER(segLimit <= oldLimit);
@@ -367,6 +375,10 @@ static Res MVFFBufferFill(Addr *baseReturn, Addr *limitReturn,
     Addr newBase, newLimit;
     foundBlock = FALSE;
     res = CBSInsert(&newBase, &newLimit, CBSOfMVFF(mvff), base, limit);
+    if (ResIsAllocFailure(res))
+      /* CBS ran out of memory for splay nodes: lose block. */
+      return res;
+
     AVER(newBase == base);
     AVER(newLimit == limit);
     AVER(res == ResOK);
@@ -722,31 +734,6 @@ static Bool MVFFCheck(MVFF mvff)
 }
 
 
-/* mps_mvff_stat -- a hack to get statistics emitted
- *
- * .stat: The SW temp pool cannot be destroyed, so we're providing this
- * to get the statistics.  It breaks modularity to access CBS internals.
- */
-
-#include "meter.h"
-extern void mps_mvff_stat(mps_pool_t pool);
-
-void mps_mvff_stat(mps_pool_t mps_pool)
-{
-  Pool pool;
-  MVFF mvff;
-
-  pool = (Pool)mps_pool;
-  AVERT(Pool, pool);
-  mvff = Pool2MVFF(pool);
-  AVERT(MVFF, mvff);
-
-  METER_EMIT(&CBSOfMVFF(mvff)->splaySearch);
-  /* FIXME: METER_EMIT(&CBSOfMVFF(mvff)->eblSearch); */
-  /* FIXME: METER_EMIT(&CBSOfMVFF(mvff)->eglSearch); */
-}
-
-
 /* C. COPYRIGHT AND LICENSE
  *
  * Copyright (C) 2001-2002 Ravenbrook Limited <http://www.ravenbrook.com/>.

mps/code/range.c

@@ -16,14 +16,13 @@ SRCID(range, "$Id$");
 Bool RangeCheck(Range range)
 {
   CHECKS(Range, range);
-  CHECKL(range != NULL);
-  CHECKL(RangeBase(range) != NULL);
-  CHECKL(RangeBase(range) <= RangeLimit(range));
+  CHECKL(range->base != NULL);
+  CHECKL(range->base <= range->limit);
 
   return TRUE;
 }
 
-Res RangeInit(Range range, Addr base, Addr limit)
+void RangeInit(Range range, Addr base, Addr limit)
 {
   AVER(range != NULL);
   AVER(base != NULL);
@@ -34,7 +33,6 @@ Res RangeInit(Range range, Addr base, Addr limit)
 
   range->sig = RangeSig;
   AVERT(Range, range);
-  return ResOK;
 }
 
 void RangeFinish(Range range)
@@ -64,7 +62,7 @@ Res RangeDescribe(Range range, mps_lib_FILE *stream)
   return ResOK;
 }
 
-Bool RangeOverlap(Range range1, Range range2)
+Bool RangesOverlap(Range range1, Range range2)
 {
   AVERT(Range, range1);
   AVERT(Range, range2);

mps/code/range.h

@@ -27,12 +27,12 @@ typedef struct RangeStruct *Range;
 #define RangeLimit(range) ((range)->limit)
 #define RangeSize(range) (AddrOffset(RangeBase(range), RangeLimit(range)))
 
-extern Res RangeInit(Range range, Addr base, Addr limit);
+extern void RangeInit(Range range, Addr base, Addr limit);
 extern void RangeFinish(Range range);
 extern Res RangeDescribe(Range range, mps_lib_FILE *stream);
 extern Bool RangeCheck(Range range);
 extern Bool RangeIsAligned(Range range, Align align);
-extern Bool RangeOverlap(Range range1, Range range2);
+extern Bool RangesOverlap(Range range1, Range range2);
 extern Addr (RangeBase)(Range range);
 extern Addr (RangeLimit)(Range range);
 extern Size (RangeSize)(Range range);

mps/design/range.txt

@@ -43,7 +43,7 @@ Interface
 inlined in client structures or allocated on the stack. Clients must
 not depend on its implementation details.
 
-``Res RangeInit(Range range, Addr base, Addr limit)``
+``void RangeInit(Range range, Addr base, Addr limit)``
 
 Initialize a range object to represent the half-open address range
 between ``base`` (inclusive) and ``limit`` (exclusive). It must be the
@@ -72,7 +72,7 @@ there is a function too.)
 Return the size of the range. (This is implemented as a macro, but
 there is a function too. The macro evaluates its argument twice.)
 
-``Bool RangeOverlap(Range range1, Range range2)``
+``Bool RangesOverlap(Range range1, Range range2)``
 
 Return ``TRUE`` if the two ranges overlap (have at least one address
 in common), or ``FALSE`` if they do not. Note that ranges [*A*, *B*) and