gc:destructors: more progress

lib/core/allocators.nim

@@ -18,6 +18,8 @@ type
     realloc*: proc (a: Allocator; p: pointer; oldSize, newSize: int): pointer {.nimcall.}
     deallocAll*: proc (a: Allocator) {.nimcall.}
     flags*: set[AllocatorFlag]
+    allocCount: int
+    deallocCount: int
 
 var
   localAllocator {.threadvar.}: Allocator
@@ -30,8 +32,10 @@ proc getLocalAllocator*(): Allocator =
     result = addr allocatorStorage
     result.alloc = proc (a: Allocator; size: int; alignment: int = 8): pointer {.nimcall.} =
       result = system.alloc(size)
+      inc a.allocCount
     result.dealloc = proc (a: Allocator; p: pointer; size: int) {.nimcall.} =
       system.dealloc(p)
+      inc a.deallocCount
     result.realloc = proc (a: Allocator; p: pointer; oldSize, newSize: int): pointer {.nimcall.} =
       result = system.realloc(p, newSize)
     result.deallocAll = nil
@@ -47,15 +51,6 @@ proc getSharedAllocator*(): Allocator =
 proc setSharedAllocator*(a: Allocator) =
   sharedAllocator = a
 
-when false:
-  proc alloc*(size: int; alignment: int = 8): pointer =
-    let a = getCurrentAllocator()
-    result = a.alloc(a, size, alignment)
-
-  proc dealloc*(p: pointer; size: int) =
-    let a = getCurrentAllocator()
-    a.dealloc(a, p, size)
-
-  proc realloc*(p: pointer; oldSize, newSize: int): pointer =
-    let a = getCurrentAllocator()
-    result = a.realloc(a, p, oldSize, newSize)
+proc allocCounters*(): (int, int) =
+  let a = getLocalAllocator()
+  result = (a.allocCount, a.deallocCount)

lib/core/seqs.nim

@@ -126,18 +126,19 @@ proc grow*[T](x: var seq[T]; newLen: Natural; value: T) =
   let oldLen = x.len
   if newLen <= oldLen: return
   var xu = cast[ptr NimSeqV2[T]](addr x)
-
-  xu.p = cast[typeof(xu.p)](prepareSeqAdd(oldLen, xu.p, newLen - oldLen, sizeof(T)))
+  if xu.p == nil or xu.p.cap < newLen:
+    xu.p = cast[typeof(xu.p)](prepareSeqAdd(oldLen, xu.p, newLen - oldLen, sizeof(T)))
   xu.len = newLen
   for i in oldLen .. newLen-1:
     xu.p.data[i] = value
 
 proc setLen[T](s: var seq[T], newlen: Natural) =
-  if newlen < s.len:
-    shrink(s, newLen)
-  else:
-    var v: T # get the default value of 'v'
-    grow(s, newLen, v)
+  {.noSideEffect.}:
+    if newlen < s.len:
+      shrink(s, newLen)
+    else:
+      var v: T # get the default value of 'v'
+      grow(s, newLen, v)
 
 when false:
   proc resize[T](s: var NimSeqV2[T]) =