fixes #5301

config/nim.cfg

@@ -100,7 +100,7 @@ path="$lib/pure"
 @if windows:
   #gcc.path = r"$nim\dist\mingw\bin"
   @if gcc:
-    tlsEmulation:on
+    #tlsEmulation:on
   @end
 @end
 
@@ -110,7 +110,13 @@ path="$lib/pure"
   gcc.options.always = "-w"
   gcc.cpp.options.always = "-w -fpermissive"
 @else:
-  gcc.options.always = "-w"
+  @if cpu32:
+    gcc.options.always = "-w -m32"
+    gcc.options.linker = "-m32"
+  @else:
+    gcc.options.always = "-w -m64"
+    gcc.options.linker = "-m64"
+  @end
   gcc.cpp.options.always = "-w -fpermissive"
 @end
 

lib/system/alloc.nim

@@ -54,7 +54,7 @@ type
   BaseChunk {.pure, inheritable.} = object
     prevSize: int        # size of previous chunk; for coalescing
     size: int            # if < PageSize it is a small chunk
-    used: bool           # later will be optimized into prevSize...
+    origSize: int        # 0th bit == 1 if 'used'
 
   SmallChunk = object of BaseChunk
     next, prev: PSmallChunk  # chunks of the same size
@@ -65,11 +65,11 @@ type
 
   BigChunk = object of BaseChunk # not necessarily > PageSize!
     next, prev: PBigChunk    # chunks of the same (or bigger) size
-    align: int
+    heapLink: PBigChunk      # linked list of all chunks for bulk 'deallocPages'
     data: AlignType      # start of usable memory
 
-template smallChunkOverhead(): expr = sizeof(SmallChunk)-sizeof(AlignType)
-template bigChunkOverhead(): expr = sizeof(BigChunk)-sizeof(AlignType)
+template smallChunkOverhead(): untyped = sizeof(SmallChunk)-sizeof(AlignType)
+template bigChunkOverhead(): untyped = sizeof(BigChunk)-sizeof(AlignType)
 
 # ------------- chunk table ---------------------------------------------------
 # We use a PtrSet of chunk starts and a table[Page, chunksize] for chunk
@@ -98,6 +98,7 @@ type
     currMem, maxMem, freeMem: int # memory sizes (allocated from OS)
     lastSize: int # needed for the case that OS gives us pages linearly
     freeChunksList: PBigChunk # XXX make this a datastructure with O(1) access
+    heapLink: PBigChunk # used to link every chunk for bulk 'deallocPages'
     chunkStarts: IntSet
     root, deleted, last, freeAvlNodes: PAvlNode
     locked, blockChunkSizeIncrease: bool # if locked, we cannot free pages.
@@ -241,7 +242,7 @@ proc isSmallChunk(c: PChunk): bool {.inline.} =
   return c.size <= SmallChunkSize-smallChunkOverhead()
 
 proc chunkUnused(c: PChunk): bool {.inline.} =
-  result = not c.used
+  result = (c.origSize and 1) == 0
 
 iterator allObjects(m: var MemRegion): pointer {.inline.} =
   m.locked = true
@@ -310,12 +311,14 @@ proc requestOsChunks(a: var MemRegion, size: int): PBigChunk =
 
   incCurrMem(a, size)
   inc(a.freeMem, size)
+  result.heapLink = a.heapLink
+  result.origSize = size
+  a.heapLink = result
 
   sysAssert((cast[ByteAddress](result) and PageMask) == 0, "requestOsChunks 1")
   #zeroMem(result, size)
   result.next = nil
   result.prev = nil
-  result.used = false
   result.size = size
   # update next.prevSize:
   var nxt = cast[ByteAddress](result) +% size
@@ -336,19 +339,21 @@ proc requestOsChunks(a: var MemRegion, size: int): PBigChunk =
     result.prevSize = 0 # unknown
   a.lastSize = size # for next request
 
-proc freeOsChunks(a: var MemRegion, p: pointer, size: int) =
-  # update next.prevSize:
-  var c = cast[PChunk](p)
-  var nxt = cast[ByteAddress](p) +% c.size
-  sysAssert((nxt and PageMask) == 0, "freeOsChunks")
-  var next = cast[PChunk](nxt)
-  if pageIndex(next) in a.chunkStarts:
-    next.prevSize = 0 # XXX used
-  excl(a.chunkStarts, pageIndex(p))
-  osDeallocPages(p, size)
-  decCurrMem(a, size)
-  dec(a.freeMem, size)
-  #c_fprintf(stdout, "[Alloc] back to OS: %ld\n", size)
+when false:
+  # with the new linked list design this is not possible anymore:
+  proc freeOsChunks(a: var MemRegion, p: pointer, size: int) =
+    # update next.prevSize:
+    var c = cast[PChunk](p)
+    var nxt = cast[ByteAddress](p) +% c.size
+    sysAssert((nxt and PageMask) == 0, "freeOsChunks")
+    var next = cast[PChunk](nxt)
+    if pageIndex(next) in a.chunkStarts:
+      next.prevSize = 0 # XXX used
+    excl(a.chunkStarts, pageIndex(p))
+    osDeallocPages(p, size)
+    decCurrMem(a, size)
+    dec(a.freeMem, size)
+    #c_fprintf(stdout, "[Alloc] back to OS: %ld\n", size)
 
 proc isAccessible(a: MemRegion, p: pointer): bool {.inline.} =
   result = contains(a.chunkStarts, pageIndex(p))
@@ -414,19 +419,20 @@ proc freeBigChunk(a: var MemRegion, c: PBigChunk) =
           excl(a.chunkStarts, pageIndex(c))
           c = cast[PBigChunk](le)
 
-  if c.size < ChunkOsReturn or doNotUnmap or a.locked:
-    incl(a, a.chunkStarts, pageIndex(c))
-    updatePrevSize(a, c, c.size)
-    listAdd(a.freeChunksList, c)
-    c.used = false
-  else:
-    freeOsChunks(a, c, c.size)
+  #if c.size < ChunkOsReturn or doNotUnmap or a.locked:
+  incl(a, a.chunkStarts, pageIndex(c))
+  updatePrevSize(a, c, c.size)
+  listAdd(a.freeChunksList, c)
+  # set 'used' to false:
+  c.origSize = c.origSize and not 1
+  #else:
+  #  freeOsChunks(a, c, c.size)
 
 proc splitChunk(a: var MemRegion, c: PBigChunk, size: int) =
   var rest = cast[PBigChunk](cast[ByteAddress](c) +% size)
   sysAssert(rest notin a.freeChunksList, "splitChunk")
   rest.size = c.size - size
-  rest.used = false
+  rest.origSize = 0 # not used and size irrelevant
   rest.next = nil
   rest.prev = nil
   rest.prevSize = size
@@ -461,7 +467,8 @@ proc getBigChunk(a: var MemRegion, size: int): PBigChunk =
       if result.size > size:
         splitChunk(a, result, size)
   result.prevSize = 0 # XXX why is this needed?
-  result.used = true
+  # set 'used' to to true:
+  result.origSize = result.origSize or 1
   incl(a, a.chunkStarts, pageIndex(result))
   dec(a.freeMem, size)
 
@@ -704,18 +711,26 @@ proc realloc(allocator: var MemRegion, p: pointer, newsize: Natural): pointer =
 
 proc deallocOsPages(a: var MemRegion) =
   # we free every 'ordinarily' allocated page by iterating over the page bits:
-  for p in elements(a.chunkStarts):
-    var page = cast[PChunk](p shl PageShift)
-    when not doNotUnmap:
-      var size = if page.size < PageSize: PageSize else: page.size
-      osDeallocPages(page, size)
-    else:
-      # Linux on PowerPC for example frees MORE than asked if 'munmap'
-      # receives the start of an originally mmap'ed memory block. This is not
-      # too bad, but we must not access 'page.size' then as that could trigger
-      # a segfault. But we don't need to access 'page.size' here anyway,
-      # because calling munmap with PageSize suffices:
-      osDeallocPages(page, PageSize)
+  var it = a.heapLink
+  while it != nil:
+    let next = it.heapLink
+    sysAssert it.origSize >= PageSize, "origSize too small"
+    # note:
+    osDeallocPages(it, it.origSize and not 1)
+    it = next
+  when false:
+    for p in elements(a.chunkStarts):
+      var page = cast[PChunk](p shl PageShift)
+      when not doNotUnmap:
+        var size = if page.size < PageSize: PageSize else: page.size
+        osDeallocPages(page, size)
+      else:
+        # Linux on PowerPC for example frees MORE than asked if 'munmap'
+        # receives the start of an originally mmap'ed memory block. This is not
+        # too bad, but we must not access 'page.size' then as that could trigger
+        # a segfault. But we don't need to access 'page.size' here anyway,
+        # because calling munmap with PageSize suffices:
+        osDeallocPages(page, PageSize)
   # And then we free the pages that are in use for the page bits:
   llDeallocAll(a)
 

lib/system/osalloc.nim

@@ -132,7 +132,7 @@ elif defined(windows):
                     header: "<windows.h>", stdcall, importc: "VirtualAlloc".}
 
   proc virtualFree(lpAddress: pointer, dwSize: int,
-                   dwFreeType: int32) {.header: "<windows.h>", stdcall,
+                   dwFreeType: int32): cint {.header: "<windows.h>", stdcall,
                    importc: "VirtualFree".}
 
   proc osAllocPages(size: int): pointer {.inline.} =
@@ -151,7 +151,10 @@ elif defined(windows):
     # Windows :-(. We have to live with MEM_DECOMMIT instead.
     # Well that used to be the case but MEM_DECOMMIT fragments the address
     # space heavily, so we now treat Windows as a strange unmap target.
-    when reallyOsDealloc: virtualFree(p, 0, MEM_RELEASE)
+    when reallyOsDealloc:
+      if virtualFree(p, 0, MEM_RELEASE) == 0:
+        cprintf "yes, failing!"
+        quit 1
     #VirtualFree(p, size, MEM_DECOMMIT)
 
 elif hostOS == "standalone":