Integrate JTempl's new OFront heap implementation using unsigned address arithmetic.

This commit is contained in:
David Brown 2016-12-19 16:00:57 +00:00
parent 6f43c272c9
commit 43117e79f7

View file

@ -8,7 +8,7 @@ MODULE Heap;
CmdNameLen = 24;
SZA = SIZE(S.ADDRESS); (* Size of address *)
Unit = 4*SZA; (* smallest possible heap block *)
nofLists = 9; (* number of free_lists *)
nofLists = 9; (* number of freelist entries excluding sentinel *)
heapSize0 = 8000*Unit; (* startup heap size *)
(* all blocks look the same:
@ -50,7 +50,7 @@ MODULE Heap;
enumPtrs-: EnumProc;
reserved1,
reserved2: LONGINT
END ;
END;
Command- = PROCEDURE;
@ -58,7 +58,7 @@ MODULE Heap;
next-: Cmd;
name-: CmdName;
cmd-: Command
END ;
END;
Finalizer = PROCEDURE(obj: S.PTR);
@ -68,7 +68,7 @@ MODULE Heap;
obj: S.ADDRESS; (* weak pointer *)
marked: BOOLEAN;
finalize: Finalizer;
END ;
END;
VAR
(* the list of loaded (=initialization started) modules *)
@ -81,10 +81,8 @@ MODULE Heap;
(* extensible heap *)
heap-: S.ADDRESS; (* the sorted list of heap chunks *)
heapNegMin: S.ADDRESS; (* Range of pointer values, used for stack collection *)
heapNegMax: S.ADDRESS;
heapPosMin: S.ADDRESS;
heapPosMax: S.ADDRESS;
heapMin: S.ADDRESS; (* Range of valid pointer values, used for stack collection *)
heapMax: S.ADDRESS;
heapsize*: S.ADDRESS; (* the sum of all heap chunk sizes *)
(* finalization candidates *)
@ -114,6 +112,9 @@ MODULE Heap;
END Unlock;
PROCEDURE -uLT(x, y: S.ADDRESS): BOOLEAN "((size_t)x < (size_t)y)";
PROCEDURE -uLE(x, y: S.ADDRESS): BOOLEAN "((size_t)x <= (size_t)y)";
(*
PROCEDURE TAS*(VAR flag:BOOLEAN): BOOLEAN; (* added for compatibility with ulmSYSTEM module; noch *)
VAR oldflag : BOOLEAN;
@ -200,13 +201,8 @@ MODULE Heap;
bigBlocks := blk; (* Prepend block to list of big blocks *)
INC(heapsize, blksz);
(* Maintain heap range limits *)
IF chnk > 0 THEN
IF chnk < heapPosMin THEN heapPosMin := blk + SZA END;
IF end > heapPosMax THEN heapPosMax := end END
ELSE (* chnk < 0 *)
IF chnk < heapNegMin THEN heapNegMin := blk + SZA END;
IF end > heapNegMax THEN heapNegMax := end END
END
IF uLT(blk + SZA, heapMin) THEN heapMin := blk + SZA END;
IF uLT(heapMax, end) THEN heapMax := end END
END;
RETURN chnk
END NewChunk;
@ -214,17 +210,17 @@ MODULE Heap;
PROCEDURE ExtendHeap(blksz: S.ADDRESS);
VAR size, chnk, j, next: S.ADDRESS;
BEGIN
IF blksz > 10000*Unit THEN size := blksz
IF uLT(10000*Unit, blksz) THEN size := blksz
ELSE size := 10000*Unit (* additional heuristics *)
END ;
END;
chnk := NewChunk(size);
IF chnk # 0 THEN
(*sorted insertion*)
IF chnk < heap THEN
IF uLT(chnk, heap) THEN
S.PUT(chnk, heap); heap := chnk
ELSE
j := heap; S.GET(j, next);
WHILE (next # 0) & (chnk - next > 0) DO
WHILE (next # 0) & uLT(next, chnk) DO
j := next;
S.GET(j, next)
END;
@ -248,13 +244,13 @@ MODULE Heap;
ASSERT(blksz MOD Unit = 0);
i0 := blksz DIV Unit; i := i0;
IF i < nofLists THEN adr := freeList[i];
IF uLT(i, nofLists) THEN adr := freeList[i];
WHILE adr = 0 DO INC(i); adr := freeList[i] END
END ;
IF i < nofLists THEN (* unlink *)
END;
IF uLT(i, nofLists) THEN (* Unlink from freelist[i] *)
S.GET(adr + nextOff, next);
freeList[i] := next;
IF i # i0 THEN (* split *)
IF i # i0 THEN (* Split *)
di := i - i0; restsize := di * Unit; end := adr + restsize;
S.PUT(end + sizeOff, blksz);
S.PUT(end + sntlOff, NoPtrSntl);
@ -264,60 +260,61 @@ MODULE Heap;
freeList[di] := adr;
INC(adr, restsize)
END
ELSE
ELSE (* Search in bigBlocks *)
adr := bigBlocks; prev := 0;
LOOP
IF adr = 0 THEN
IF adr = 0 THEN (* Nothing free *)
IF firstTry THEN
GC(TRUE); INC(blksz, Unit);
IF (heapsize - allocated - blksz) * 4 < heapsize THEN
(* heap is still almost full; expand to avoid thrashing *)
IF uLT(heapsize - allocated, blksz)
OR uLT((heapsize - allocated - blksz) * 4, heapsize) THEN
(* heap would still be more than 3/4 full; expand to avoid thrashing *)
ExtendHeap((allocated + blksz) DIV (3*Unit) * (4*Unit) - heapsize)
END ;
END;
firstTry := FALSE; new := NEWREC(tag); firstTry := TRUE;
IF new = NIL THEN
(* depending on the fragmentation, the heap may not have been extended by
the anti-thrashing heuristics above *)
ExtendHeap((allocated + blksz) DIV (3*Unit) * (4*Unit) - heapsize);
new := NEWREC(tag); (* will find a free block if heap has been expanded properly *)
END ;
END;
Unlock(); RETURN new
ELSE
Unlock(); RETURN NIL
END
END ;
END;
S.GET(adr+sizeOff, t);
IF t >= blksz THEN EXIT END ;
IF uLE(blksz, t) THEN EXIT END;
prev := adr; S.GET(adr + nextOff, adr)
END ;
END;
restsize := t - blksz; end := adr + restsize;
S.PUT(end + sizeOff, blksz);
S.PUT(end + sntlOff, NoPtrSntl);
S.PUT(end, end + sizeOff);
IF restsize > nofLists * Unit THEN (*resize*)
IF uLT(nofLists * Unit, restsize) THEN (* Resize *)
S.PUT(adr + sizeOff, restsize)
ELSE (*unlink*)
ELSE (* Unlink *)
S.GET(adr + nextOff, next);
IF prev = 0 THEN bigBlocks := next
ELSE S.PUT(prev + nextOff, next);
END ;
IF restsize > 0 THEN (*move*)
END;
IF restsize # 0 THEN (* Move *)
di := restsize DIV Unit;
S.PUT(adr + sizeOff, restsize);
S.PUT(adr + nextOff, freeList[di]);
freeList[di] := adr
END
END ;
END;
INC(adr, restsize)
END ;
END;
i := adr + 4*SZA; end := adr + blksz;
WHILE end - i > 0 DO (*deliberately unrolled*)
WHILE uLT(i, end) DO (* Deliberately unrolled *)
S.PUT(i, AddressZero);
S.PUT(i + SZA, AddressZero);
S.PUT(i + 2*SZA, AddressZero);
S.PUT(i + 3*SZA, AddressZero);
INC(i, 4*SZA)
END ;
END;
S.PUT(adr + nextOff, AddressZero);
S.PUT(adr, tag);
S.PUT(adr + sizeOff, AddressZero);
@ -355,7 +352,7 @@ MODULE Heap;
S.GET(tag, offset); (* Get next ptr field offset *)
IF offset < 0 THEN (* Sentinel reached: Value is -8*(#fields+1) *)
S.PUT(q - SZA, tag + offset + 1); (* Rotate base ptr into tag *)
IF p = 0 THEN EXIT END ;
IF p = 0 THEN EXIT END;
n := q; q := p;
S.GET(q - SZA, tag); DEC(tag, 1);
S.GET(tag, offset); fld := q + offset;
@ -373,7 +370,7 @@ MODULE Heap;
tag := tagbits
END
END
END ;
END;
INC(tag, SZA)
END
END
@ -388,24 +385,24 @@ MODULE Heap;
PROCEDURE Scan;
VAR chnk, adr, end, start, tag, i, size, freesize: S.ADDRESS;
BEGIN bigBlocks := 0; i := 1;
WHILE i < nofLists DO freeList[i] := 0; INC(i) END ;
WHILE i < nofLists DO freeList[i] := 0; INC(i) END;
freesize := 0; allocated := 0; chnk := heap;
WHILE chnk # 0 DO
adr := chnk + blkOff;
S.GET(chnk + endOff, end);
WHILE end - adr > 0 DO
WHILE uLT(adr, end) DO
S.GET(adr, tag);
IF ODD(tag) THEN (*marked*)
IF freesize > 0 THEN
IF ODD(tag) THEN (* Marked *)
IF freesize # 0 THEN
start := adr - freesize;
S.PUT(start, start+SZA);
S.PUT(start+sizeOff, freesize);
S.PUT(start+sntlOff, NoPtrSntl);
i := freesize DIV Unit; freesize := 0;
IF i < nofLists THEN S.PUT(start + nextOff, freeList[i]); freeList[i] := start
ELSE S.PUT(start + nextOff, bigBlocks); bigBlocks := start
IF uLT(i, nofLists) THEN S.PUT(start + nextOff, freeList[i]); freeList[i] := start
ELSE S.PUT(start + nextOff, bigBlocks); bigBlocks := start
END
END ;
END;
DEC(tag, 1);
S.PUT(adr, tag);
S.GET(tag, size);
@ -416,17 +413,17 @@ MODULE Heap;
INC(freesize, size);
INC(adr, size)
END
END ;
IF freesize > 0 THEN (*collect last block*)
END;
IF freesize # 0 THEN (* Collect last block *)
start := adr - freesize;
S.PUT(start, start+SZA);
S.PUT(start+sizeOff, freesize);
S.PUT(start+sntlOff, NoPtrSntl);
i := freesize DIV Unit; freesize := 0;
IF i < nofLists THEN S.PUT(start + nextOff, freeList[i]); freeList[i] := start
ELSE S.PUT(start + nextOff, bigBlocks); bigBlocks := start
IF uLT(i, nofLists) THEN S.PUT(start + nextOff, freeList[i]); freeList[i] := start
ELSE S.PUT(start + nextOff, bigBlocks); bigBlocks := start
END
END ;
END;
S.GET(chnk, chnk)
END
END Scan;
@ -435,8 +432,8 @@ MODULE Heap;
VAR i, j, x: S.ADDRESS;
BEGIN j := l; x := a[j];
LOOP i := j; j := 2*j + 1;
IF (j < r) & (a[j] < a[j+1]) THEN INC(j) END;
IF (j > r) OR (a[j] <= x) THEN EXIT END;
IF (j < r) & uLT(a[j], a[j+1]) THEN INC(j) END;
IF (j > r) OR uLE(a[j], x) THEN EXIT END;
a[i] := a[j]
END;
a[i] := x
@ -449,29 +446,27 @@ MODULE Heap;
WHILE r > 0 DO x := a[0]; a[0] := a[r]; a[r] := x; DEC(r); Sift(l, r, a) END
END HeapSort;
PROCEDURE MarkCandidates(n: S.ADDRESS; VAR cand: ARRAY OF S.ADDRESS);
VAR chnk, adr, tag, next, lim, lim1, i, ptr, size: S.ADDRESS;
PROCEDURE MarkCandidates(n: LONGINT; VAR cand: ARRAY OF S.ADDRESS);
VAR chnk, end, adr, tag, next, i, ptr, size: S.ADDRESS;
BEGIN
chnk := heap; i := 0; lim := cand[n-1];
WHILE (chnk # 0 ) & (lim - chnk > 0) DO
ASSERT(n > 0);
chnk := heap; i := 0;
WHILE chnk # 0 DO
S.GET(chnk + endOff, end);
adr := chnk + blkOff;
S.GET(chnk + endOff, lim1);
IF lim1 - lim > 0 THEN lim1 := lim END ;
WHILE lim1 - adr > 0 DO
WHILE uLT(adr, end) DO
S.GET(adr, tag);
IF ODD(tag) THEN (*already marked*)
S.GET(tag-1, size); INC(adr, size)
S.GET(tag-1, size); INC(adr, size); ptr := adr + SZA;
WHILE uLT(cand[i], ptr) DO INC(i); IF i = n THEN RETURN END END ;
ELSE
S.GET(tag, size);
ptr := adr + SZA;
WHILE ptr - cand[i] > 0 DO INC(i) END ;
IF i = n THEN RETURN END ;
next := adr + size;
IF next - cand[i] > 0 THEN Mark(ptr) END ;
adr := next
END
S.GET(tag, size); ptr := adr + SZA; INC(adr, size);
WHILE uLT(cand[i], ptr) DO INC(i); IF i = n THEN RETURN END END ;
IF uLT(cand[i], adr) THEN Mark(ptr) END
END ;
IF uLE(end, cand[i]) THEN (*skip rest of this heap chunk*) adr := end END
END ;
S.GET(chnk, chnk)
S.GET(chnk + nextChnkOff, chnk)
END
END MarkCandidates;
@ -483,7 +478,7 @@ MODULE Heap;
S.GET(n.obj - SZA, tag);
IF ~ODD(tag) THEN n.marked := FALSE; Mark(n.obj)
ELSE n.marked := TRUE
END ;
END;
n := n.next
END
END CheckFin;
@ -493,7 +488,7 @@ MODULE Heap;
BEGIN n := fin; prev := NIL;
WHILE n # NIL DO
IF ~n.marked THEN
IF n = fin THEN fin := fin.next ELSE prev.next := n.next END ;
IF n = fin THEN fin := fin.next ELSE prev.next := n.next END;
n.finalize(S.VAL(S.PTR, n.obj));
(* new nodes may have been pushed in n.finalize, therefore: *)
IF prev = NIL THEN n := fin ELSE n := n.next END
@ -518,28 +513,27 @@ MODULE Heap;
PROCEDURE MarkStack(n: S.ADDRESS; VAR cand: ARRAY OF S.ADDRESS);
VAR
frame: S.PTR;
inc, nofcand: S.ADDRESS;
sp, p, stack0: S.ADDRESS;
align: RECORD ch: CHAR; p: S.PTR END ;
nofcand: LONGINT;
inc, sp, p, stack0: S.ADDRESS;
align: RECORD ch: CHAR; p: S.PTR END;
BEGIN
IF n > 0 THEN MarkStack(n-1, cand); (* flush register windows by means of recursive calls *)
IF n > 100 THEN RETURN END (* prevent tail recursion optimization *)
END ;
END;
IF n = 0 THEN
nofcand := 0; sp := S.ADR(frame);
stack0 := ModulesMainStackFrame();
(* check for minimum alignment of pointers *)
inc := S.ADR(align.p) - S.ADR(align);
IF sp - stack0 > 0 THEN inc := -inc END ;
IF uLT(stack0, sp) THEN inc := -inc END;
WHILE sp # stack0 DO
S.GET(sp, p);
IF (p > 0) & (p >= heapPosMin) & (p < heapPosMax)
OR (p < 0) & (p >= heapNegMin) & (p < heapNegMax) THEN
IF nofcand = LEN(cand) THEN HeapSort(nofcand, cand); MarkCandidates(nofcand, cand); nofcand := 0 END ;
IF uLE(heapMin, p) & uLT(p, heapMax) THEN
IF nofcand = LEN(cand) THEN HeapSort(nofcand, cand); MarkCandidates(nofcand, cand); nofcand := 0 END;
cand[nofcand] := p; INC(nofcand)
END ;
END;
INC(sp, inc)
END ;
END;
IF nofcand > 0 THEN HeapSort(nofcand, cand); MarkCandidates(nofcand, cand) END
END
END MarkStack;
@ -555,9 +549,9 @@ MODULE Heap;
Lock();
m := S.VAL(Module, modules);
WHILE m # NIL DO
IF m.enumPtrs # NIL THEN m.enumPtrs(MarkP) END ;
IF m.enumPtrs # NIL THEN m.enumPtrs(MarkP) END;
m := m^.next
END ;
END;
IF markStack THEN
(* generate register pressure to force callee saved registers to memory;
may be simplified by inlining OS calls or processor specific instructions
@ -569,10 +563,10 @@ MODULE Heap;
INC(i8, 9); INC(i9, 10); INC(i10, 11); INC(i11, 12); INC(i12, 13); INC(i13, 14); INC(i14, 15); INC(i15, 16);
INC(i16, 17); INC(i17, 18); INC(i18, 19); INC(i19, 20); INC(i20, 21); INC(i21, 22); INC(i22, 23); INC(i23, 24);
IF (i0 = -99) & (i15 = 24) THEN MarkStack(32, cand); EXIT END
END ;
END;
IF i0 + i1 + i2 + i3 + i4 + i5 + i6 + i7 + i8 + i9 + i10 + i11 + i12 + i13 + i14 + i15
+ i16 + i17 + i18 + i19 + i20 + i21 + i22 + i23 > 10000 THEN RETURN (* use all variables *)
END ;
END;
END;
CheckFin;
Scan;
@ -600,20 +594,18 @@ MODULE Heap;
heapsize := 0;
allocated := 0;
lockdepth := 0;
heapPosMin := MAX(S.ADDRESS);
heapPosMax := 0;
heapNegMin := 0;
heapNegMax := MIN(S.ADDRESS);
heapMin := -1; (* all bits set *)
heapMax := 0;
bigBlocks := 0;
heap := NewChunk(heapSize0);
S.PUT(heap + nextChnkOff, AddressZero);
firstTry := TRUE;
freeList[nofLists] := 1;
freeList[nofLists] := 1; (* Sentinel, # 0 *)
FileCount := 0;
modules := NIL;
bigBlocks := 0;
fin := NIL;
interrupted := FALSE;