new implementations for --gc:orc (#14121)

* cycle collector: new implementation
* cycle collector: make self-adaptive based on its previous effectiveness
* cycle collector: added Lins's jump stack to improve traversal from 3*N to 2*N
* cycle collector: make tests green
* API extensions and bugfixes
* code cleanup and use --gc:orc for tasyncawait

tests/arc/tasyncawait.nim

@@ -1,6 +1,6 @@
 discard """
   outputsub: "result: 5000"
-  cmd: "nim c --gc:arc $file"
+  cmd: "nim c --gc:orc $file"
 """
 
 import asyncdispatch, asyncnet, nativesockets, net, strutils, os
@@ -71,4 +71,5 @@ main()
 
 assert msgCount == swarmSize * messagesToSend
 echo "result: ", msgCount
+GC_fullCollect()
 echo "memory: ", formatSize(getOccupiedMem() - mem)

tests/destructor/tarc2.nim

@@ -27,4 +27,5 @@ proc main(rootName: string) =
 
 let mem = getOccupiedMem()
 main("yeah")
+GC_fullCollect()
 echo "leak: ", getOccupiedMem() - mem > 0

tests/destructor/tasync_prototype_cyclic.nim

@@ -51,4 +51,5 @@ proc main =
   discard serve(PAsyncHttpServer(value: "asdas"))
 
 main()
+GC_fullCollect()
 echo "MEMORY ", getOccupiedMem() - mem

tests/destructor/tcycle1.nim

@@ -50,4 +50,5 @@ proc main =
 
 let mem = getOccupiedMem()
 main()
+GC_fullCollect()
 echo "MEM ", getOccupiedMem() - mem

tests/destructor/tcycle2.nim

@@ -15,4 +15,6 @@ proc main(x: int) =
 
 let mem = getOccupiedMem()
 main(90)
+GC_fullCollect()
+
 echo "MEM ", getOccupiedMem() - mem

tests/destructor/tcycle3.nim

@@ -61,4 +61,5 @@ proc main =
 
 let mem = getOccupiedMem()
 main()
+GC_fullCollect()
 echo getOccupiedMem() - mem

tests/gc/thavlak.nim

@@ -394,7 +394,7 @@ proc run(self: var LoopTesterApp) =
   echo "Constructing CFG..."
   var n = 2
 
-  when not defined(gcOrc):
+  when true: # not defined(gcOrc):
     # currently cycle detection is so slow that we disable this part
     for parlooptrees in 1..10:
       discard self.cfg.createNode(n + 1)
@@ -437,4 +437,5 @@ proc main =
 let mem = getOccupiedMem()
 main()
 when defined(gcOrc):
+  GC_fullCollect()
   doAssert getOccupiedMem() == mem