Branch imports for masters.

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1 files changed, 81 insertions, 0 deletions

diff --git a/mps/code/ref.c b/mps/code/ref.c
new file mode 100644
index 00000000000..8614cd5b451
--- /dev/null
+++ b/mps/code/ref.c
@@ -0,0 +1,81 @@
+/* impl.c.ref: REFERENCES
+ *
+ * $HopeName: MMsrc!ref.c(trunk.12) $
+ * Copyright (C) 1999 Harlequin Limited.  All rights reserved.
+ *
+ * .purpose: Implement operations on Ref, RefSet, ZoneSet, and Rank.
+ *
+ * .design: See design.mps.ref and design.mps.refset.
+ */
+
+#include "mpm.h"
+
+SRCID(ref, "$HopeName: MMsrc!ref.c(trunk.12) $");
+
+
+/* RankCheck -- check a rank value */
+
+Bool RankCheck(Rank rank)
+{
+  CHECKL(rank < RankLIMIT);
+  UNUSED(rank); /* impl.c.mpm.check.unused */
+  return TRUE;
+}
+
+
+/* RankSetCheck -- check a rank set */
+
+Bool RankSetCheck(RankSet rankSet)
+{
+  CHECKL(rankSet < (1uL << RankLIMIT));
+  UNUSED(rankSet); /* impl.c.mpm.check.unused */
+  return TRUE;
+}
+
+
+/* ZoneSetOfRange -- calculate the zone set of a range of addresses */
+
+RefSet ZoneSetOfRange(Arena arena, Addr base, Addr limit)
+{
+  Word zbase, zlimit;
+
+  AVERT(Arena, arena);
+  AVER(limit > base);
+
+  /* The base and limit zones of the range are calculated.  The limit */
+  /* zone is the zone after the last zone of the range, not the zone of */
+  /* the limit address. */
+  zbase = (Word)base >> arena->zoneShift;
+  zlimit = (((Word)limit-1) >> arena->zoneShift) + 1;
+
+
+  /* If the range is large enough to span all zones, its zone set is */
+  /* universal. */
+  if (zlimit - zbase >= MPS_WORD_WIDTH)
+    return ZoneSetUNIV;
+
+  zbase  &= MPS_WORD_WIDTH - 1;
+  zlimit &= MPS_WORD_WIDTH - 1;
+
+  /* If the base zone is less than the limit zone, the zone set looks */
+  /* like 000111100, otherwise it looks like 111000011. */
+  if (zbase < zlimit)
+    return ((ZoneSet)1<<zlimit) - ((ZoneSet)1<<zbase);
+  else
+    return ~(((ZoneSet)1<<zbase) - ((ZoneSet)1<<zlimit));
+}
+
+
+/* ZoneSetOfSeg -- calculate the zone set of segment addresses
+ *
+ * .rsor.def: The zone set of a segment is the union of the zones the
+ * segment occupies.
+ */
+
+ZoneSet ZoneSetOfSeg(Arena arena, Seg seg)
+{
+  /* arena is checked by ZoneSetOfRange */
+  AVERT(Seg, seg);
+
+  return ZoneSetOfRange(arena, SegBase(seg), SegLimit(seg));
+}