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/* Copyright (C) 2012 Matthew Fluet.
* Copyright (C) 1999-2008 Henry Cejtin, Matthew Fluet, Suresh
* Jagannathan, and Stephen Weeks.
* Copyright (C) 1997-2000 NEC Research Institute.
*
* MLton is released under a BSD-style license.
* See the file MLton-LICENSE for details.
*/
/* ---------------------------------------------------------------- */
/* Cheney Copying Collection */
/* ---------------------------------------------------------------- */
void updateWeaksForCheneyCopy (GC_state s) {
pointer p;
GC_weak w;
for (w = s->weaks; w != NULL; w = w->link) {
assert (BOGUS_OBJPTR != w->objptr);
if (DEBUG_WEAK)
fprintf (stderr, "updateWeaksForCheneyCopy w = "FMTPTR" ", (uintptr_t)w);
p = objptrToPointer (w->objptr, s->heap.start);
if (GC_FORWARDED == getHeader (p)) {
if (DEBUG_WEAK)
fprintf (stderr, "forwarded from "FMTOBJPTR" to "FMTOBJPTR"\n",
w->objptr,
*(objptr*)p);
w->objptr = *(objptr*)p;
} else {
if (DEBUG_WEAK)
fprintf (stderr, "cleared\n");
*(getHeaderp((pointer)w - offsetofWeak (s))) = GC_WEAK_GONE_HEADER;
w->objptr = BOGUS_OBJPTR;
}
}
s->weaks = NULL;
}
void swapHeapsForCheneyCopy (GC_state s) {
struct GC_heap tempHeap;
tempHeap = s->secondaryHeap;
s->secondaryHeap = s->heap;
s->heap = tempHeap;
setCardMapAndCrossMap (s);
}
void majorCheneyCopyGC (GC_state s) {
size_t bytesCopied;
struct rusage ru_start;
pointer toStart;
assert (s->secondaryHeap.size >= s->heap.oldGenSize);
if (detailedGCTime (s))
startTiming (&ru_start);
s->cumulativeStatistics.numCopyingGCs++;
s->forwardState.amInMinorGC = FALSE;
if (DEBUG or s->controls.messages) {
fprintf (stderr,
"[GC: Starting major Cheney-copy;]\n");
fprintf (stderr,
"[GC:\tfrom heap at "FMTPTR" of size %s bytes,]\n",
(uintptr_t)(s->heap.start),
uintmaxToCommaString(s->heap.size));
fprintf (stderr,
"[GC:\tto heap at "FMTPTR" of size %s bytes.]\n",
(uintptr_t)(s->secondaryHeap.start),
uintmaxToCommaString(s->secondaryHeap.size));
}
s->forwardState.toStart = s->secondaryHeap.start;
s->forwardState.toLimit = s->secondaryHeap.start + s->secondaryHeap.size;
assert (s->secondaryHeap.start != (pointer)NULL);
/* The next assert ensures there is enough space for the copy to
* succeed. It does not assert
* (s->secondaryHeap.size >= s->heap.size)
* because that is too strong.
*/
assert (s->secondaryHeap.size >= s->heap.oldGenSize);
toStart = alignFrontier (s, s->secondaryHeap.start);
s->forwardState.back = toStart;
foreachGlobalObjptr (s, forwardObjptr);
foreachObjptrInRange (s, toStart, &s->forwardState.back, forwardObjptr, TRUE);
updateWeaksForCheneyCopy (s);
s->secondaryHeap.oldGenSize = (size_t)(s->forwardState.back - s->secondaryHeap.start);
bytesCopied = s->secondaryHeap.oldGenSize;
s->cumulativeStatistics.bytesCopied += bytesCopied;
swapHeapsForCheneyCopy (s);
s->lastMajorStatistics.kind = GC_COPYING;
if (detailedGCTime (s))
stopTiming (&ru_start, &s->cumulativeStatistics.ru_gcCopying);
if (DEBUG or s->controls.messages)
fprintf (stderr,
"[GC: Finished major Cheney-copy; copied %s bytes.]\n",
uintmaxToCommaString(bytesCopied));
}
/* ---------------------------------------------------------------- */
/* Minor Cheney Copying Collection */
/* ---------------------------------------------------------------- */
void minorCheneyCopyGC (GC_state s) {
size_t bytesAllocated;
size_t bytesCopied;
struct rusage ru_start;
if (DEBUG_GENERATIONAL)
fprintf (stderr, "minorGC nursery = "FMTPTR" frontier = "FMTPTR"\n",
(uintptr_t)s->heap.nursery, (uintptr_t)s->frontier);
assert (invariantForGC (s));
bytesAllocated = (size_t)(s->frontier - s->heap.nursery);
if (bytesAllocated == 0)
return;
s->cumulativeStatistics.bytesAllocated += bytesAllocated;
if (not s->canMinor) {
s->heap.oldGenSize += bytesAllocated;
} else {
if (detailedGCTime (s))
startTiming (&ru_start);
s->cumulativeStatistics.numMinorGCs++;
s->forwardState.amInMinorGC = TRUE;
if (DEBUG_GENERATIONAL or s->controls.messages) {
fprintf (stderr,
"[GC: Starting minor Cheney-copy;]\n");
fprintf (stderr,
"[GC:\tfrom nursery at "FMTPTR" of size %s bytes.]\n",
(uintptr_t)(s->heap.nursery),
uintmaxToCommaString(bytesAllocated));
}
s->forwardState.toStart = s->heap.start + s->heap.oldGenSize;
assert (isFrontierAligned (s, s->forwardState.toStart));
s->forwardState.toLimit = s->forwardState.toStart + bytesAllocated;
assert (invariantForGC (s));
s->forwardState.back = s->forwardState.toStart;
/* Forward all globals. Would like to avoid doing this once all
* the globals have been assigned.
*/
foreachGlobalObjptr (s, forwardObjptrIfInNursery);
forwardInterGenerationalObjptrs (s);
foreachObjptrInRange (s, s->forwardState.toStart, &s->forwardState.back,
forwardObjptrIfInNursery, TRUE);
updateWeaksForCheneyCopy (s);
bytesCopied = (size_t)(s->forwardState.back - s->forwardState.toStart);
s->cumulativeStatistics.bytesCopiedMinor += bytesCopied;
s->heap.oldGenSize += bytesCopied;
s->lastMajorStatistics.numMinorGCs++;
if (detailedGCTime (s))
stopTiming (&ru_start, &s->cumulativeStatistics.ru_gcMinor);
if (DEBUG_GENERATIONAL or s->controls.messages)
fprintf (stderr,
"[GC: Finished minor Cheney-copy; copied %s bytes.]\n",
uintmaxToCommaString(bytesCopied));
}
}
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