diff options
Diffstat (limited to 'lib/system/alloc.nim')
| -rwxr-xr-x | lib/system/alloc.nim | 71 |
1 files changed, 29 insertions, 42 deletions
diff --git a/lib/system/alloc.nim b/lib/system/alloc.nim index 2280415e1..c12dc253a 100755 --- a/lib/system/alloc.nim +++ b/lib/system/alloc.nim @@ -1,7 +1,7 @@ # # # Nimrod's Runtime Library -# (c) Copyright 2009 Andreas Rumpf +# (c) Copyright 2011 Andreas Rumpf # # See the file "copying.txt", included in this # distribution, for details about the copyright. @@ -80,7 +80,7 @@ else: # system immediately. const - ChunkOsReturn = 256 * PageSize + ChunkOsReturn = 256 * PageSize # 1 MB InitialMemoryRequest = ChunkOsReturn div 2 # < ChunkOsReturn! SmallChunkSize = PageSize @@ -101,6 +101,7 @@ type next: ptr TFreeCell # next free cell in chunk (overlaid with refcount) zeroField: int # 0 means cell is not used (overlaid with typ field) # 1 means cell is manually managed pointer + # otherwise a PNimType is stored in there PChunk = ptr TBaseChunk PBigChunk = ptr TBigChunk @@ -151,6 +152,7 @@ type TAllocator {.final, pure.} = object llmem: PLLChunk currMem, maxMem, freeMem: int # memory sizes (allocated from OS) + lastSize: int # needed for the case that OS gives us pages linearly freeSmallChunks: array[0..SmallChunkSize div MemAlign-1, PSmallChunk] freeChunksList: PBigChunk # XXX make this a datastructure with O(1) access chunkStarts: TIntSet @@ -167,10 +169,7 @@ proc getMaxMem(a: var TAllocator): int = # maxPagesCount may not be up to date. Thus we use the # maximum of these both values here: return max(a.currMem, a.maxMem) - -var - allocator: TAllocator - + proc llAlloc(a: var TAllocator, size: int): pointer = # *low-level* alloc for the memory managers data structures. Deallocation # is never done. @@ -192,10 +191,10 @@ proc IntSetGet(t: TIntSet, key: int): PTrunk = it = it.next result = nil -proc IntSetPut(t: var TIntSet, key: int): PTrunk = +proc IntSetPut(a: var TAllocator, t: var TIntSet, key: int): PTrunk = result = IntSetGet(t, key) if result == nil: - result = cast[PTrunk](llAlloc(allocator, sizeof(result[]))) + result = cast[PTrunk](llAlloc(a, sizeof(result[]))) result.next = t.data[key and high(t.data)] t.data[key and high(t.data)] = result result.key = key @@ -208,8 +207,8 @@ proc Contains(s: TIntSet, key: int): bool = else: result = false -proc Incl(s: var TIntSet, key: int) = - var t = IntSetPut(s, key shr TrunkShift) +proc Incl(a: var TAllocator, s: var TIntSet, key: int) = + var t = IntSetPut(a, s, key shr TrunkShift) var u = key and TrunkMask t.bits[u shr IntShift] = t.bits[u shr IntShift] or (1 shl (u and IntMask)) @@ -219,18 +218,6 @@ proc Excl(s: var TIntSet, key: int) = var u = key and TrunkMask t.bits[u shr IntShift] = t.bits[u shr IntShift] and not (1 shl (u and IntMask)) - -proc ContainsOrIncl(s: var TIntSet, key: int): bool = - var t = IntSetGet(s, key shr TrunkShift) - if t != nil: - var u = key and TrunkMask - result = (t.bits[u shr IntShift] and (1 shl (u and IntMask))) != 0 - if not result: - t.bits[u shr IntShift] = t.bits[u shr IntShift] or - (1 shl (u and IntMask)) - else: - Incl(s, key) - result = false # ------------- chunk management ---------------------------------------------- proc pageIndex(c: PChunk): int {.inline.} = @@ -241,9 +228,7 @@ proc pageIndex(p: pointer): int {.inline.} = proc pageAddr(p: pointer): PChunk {.inline.} = result = cast[PChunk](cast[TAddress](p) and not PageMask) - assert(Contains(allocator.chunkStarts, pageIndex(result))) - -var lastSize = PageSize + #assert(Contains(allocator.chunkStarts, pageIndex(result))) proc requestOsChunks(a: var TAllocator, size: int): PBigChunk = incCurrMem(a, size) @@ -263,6 +248,7 @@ proc requestOsChunks(a: var TAllocator, size: int): PBigChunk = #echo("Next already allocated!") next.prevSize = size # set result.prevSize: + var lastSize = if a.lastSize != 0: a.lastSize else: PageSize var prv = cast[TAddress](result) -% lastSize assert((nxt and PageMask) == 0) var prev = cast[PChunk](prv) @@ -271,7 +257,7 @@ proc requestOsChunks(a: var TAllocator, size: int): PBigChunk = result.prevSize = lastSize else: result.prevSize = 0 # unknown - lastSize = size # for next request + a.lastSize = size # for next request proc freeOsChunks(a: var TAllocator, p: pointer, size: int) = # update next.prevSize: @@ -287,8 +273,8 @@ proc freeOsChunks(a: var TAllocator, p: pointer, size: int) = dec(a.freeMem, size) #c_fprintf(c_stdout, "[Alloc] back to OS: %ld\n", size) -proc isAccessible(p: pointer): bool {.inline.} = - result = Contains(allocator.chunkStarts, pageIndex(p)) +proc isAccessible(a: TAllocator, p: pointer): bool {.inline.} = + result = Contains(a.chunkStarts, pageIndex(p)) proc contains[T](list, x: T): bool = var it = list @@ -337,7 +323,7 @@ proc updatePrevSize(a: var TAllocator, c: PBigChunk, prevSize: int) {.inline.} = var ri = cast[PChunk](cast[TAddress](c) +% c.size) assert((cast[TAddress](ri) and PageMask) == 0) - if isAccessible(ri): + if isAccessible(a, ri): ri.prevSize = prevSize proc freeBigChunk(a: var TAllocator, c: PBigChunk) = @@ -347,7 +333,7 @@ proc freeBigChunk(a: var TAllocator, c: PBigChunk) = when coalescRight: var ri = cast[PChunk](cast[TAddress](c) +% c.size) assert((cast[TAddress](ri) and PageMask) == 0) - if isAccessible(ri) and chunkUnused(ri): + if isAccessible(a, ri) and chunkUnused(ri): assert(not isSmallChunk(ri)) if not isSmallChunk(ri): ListRemove(a.freeChunksList, cast[PBigChunk](ri)) @@ -357,7 +343,7 @@ proc freeBigChunk(a: var TAllocator, c: PBigChunk) = if c.prevSize != 0: var le = cast[PChunk](cast[TAddress](c) -% c.prevSize) assert((cast[TAddress](le) and PageMask) == 0) - if isAccessible(le) and chunkUnused(le): + if isAccessible(a, le) and chunkUnused(le): assert(not isSmallChunk(le)) if not isSmallChunk(le): ListRemove(a.freeChunksList, cast[PBigChunk](le)) @@ -366,7 +352,7 @@ proc freeBigChunk(a: var TAllocator, c: PBigChunk) = c = cast[PBigChunk](le) if c.size < ChunkOsReturn: - incl(a.chunkStarts, pageIndex(c)) + incl(a, a.chunkStarts, pageIndex(c)) updatePrevSize(a, c, c.size) ListAdd(a.freeChunksList, c) c.used = false @@ -383,7 +369,7 @@ proc splitChunk(a: var TAllocator, c: PBigChunk, size: int) = rest.prevSize = size updatePrevSize(a, c, rest.size) c.size = size - incl(a.chunkStarts, pageIndex(rest)) + incl(a, a.chunkStarts, pageIndex(rest)) ListAdd(a.freeChunksList, rest) proc getBigChunk(a: var TAllocator, size: int): PBigChunk = @@ -410,7 +396,7 @@ proc getBigChunk(a: var TAllocator, size: int): PBigChunk = result = requestOsChunks(a, size) result.prevSize = 0 # XXX why is this needed? result.used = true - incl(a.chunkStarts, pageIndex(result)) + incl(a, a.chunkStarts, pageIndex(result)) dec(a.freeMem, size) proc getSmallChunk(a: var TAllocator): PSmallChunk = @@ -472,7 +458,7 @@ proc rawAlloc(a: var TAllocator, requestedSize: int): pointer = assert c.size == size result = addr(c.data) assert((cast[TAddress](result) and (MemAlign-1)) == 0) - assert(isAccessible(result)) + assert(isAccessible(a, result)) proc rawDealloc(a: var TAllocator, p: pointer) = var c = pageAddr(p) @@ -509,7 +495,7 @@ proc rawDealloc(a: var TAllocator, p: pointer) = freeBigChunk(a, cast[PBigChunk](c)) proc isAllocatedPtr(a: TAllocator, p: pointer): bool = - if isAccessible(p): + if isAccessible(a, p): var c = pageAddr(p) if not chunkUnused(c): if isSmallChunk(c): @@ -522,11 +508,12 @@ proc isAllocatedPtr(a: TAllocator, p: pointer): bool = var c = cast[PBigChunk](c) result = p == addr(c.data) and cast[ptr TFreeCell](p).zeroField >% 1 +var + allocator {.rtlThreadVar.}: TAllocator + # ---------------------- interface to programs ------------------------------- when not defined(useNimRtl): - var heapLock: TSysLock - InitSysLock(HeapLock) proc unlockedAlloc(size: int): pointer {.inline.} = result = rawAlloc(allocator, size+sizeof(TFreeCell)) @@ -545,18 +532,18 @@ when not defined(useNimRtl): assert(not isAllocatedPtr(allocator, x)) proc alloc(size: int): pointer = - when hasThreadSupport: AquireSys(HeapLock) + when hasThreadSupport and hasSharedHeap: AquireSys(HeapLock) result = unlockedAlloc(size) - when hasThreadSupport: ReleaseSys(HeapLock) + when hasThreadSupport and hasSharedHeap: ReleaseSys(HeapLock) proc alloc0(size: int): pointer = result = alloc(size) zeroMem(result, size) proc dealloc(p: pointer) = - when hasThreadSupport: AquireSys(HeapLock) + when hasThreadSupport and hasSharedHeap: AquireSys(HeapLock) unlockedDealloc(p) - when hasThreadSupport: ReleaseSys(HeapLock) + when hasThreadSupport and hasSharedHeap: ReleaseSys(HeapLock) proc ptrSize(p: pointer): int = var x = cast[pointer](cast[TAddress](p) -% sizeof(TFreeCell)) |