Minor changes and fixes

src/backend/vm.nim

@@ -25,7 +25,7 @@ import ../frontend/meta/bytecode
 import ../util/multibyte
 
 
-when debugVM or debugMem:
+when debugVM or debugMem or debugGC:
     import std/strformat
     import std/terminal
 
@@ -97,7 +97,6 @@ proc collect*(self: PeonGC)
 
 proc reallocate*(self: PeonGC, p: pointer, oldSize: int, newSize: int): pointer =
     ## Simple wrapper around realloc/dealloc
-    self.bytesAllocated.total += newSize - oldSize
     self.bytesAllocated.current += newSize - oldSize
     if self.bytesAllocated.current > self.nextGC:
         self.collect()
@@ -110,6 +109,7 @@ proc reallocate*(self: PeonGC, p: pointer, oldSize: int, newSize: int): pointer
                     echo "DEBUG - Memory manager: Deallocating 1 byte of memory"
             dealloc(p)
         elif (oldSize > 0 and not p.isNil() and newSize > oldSize) or oldSize == 0:
+            self.bytesAllocated.total += newSize - oldSize
             when debugStressGC:
                 self.collect()
             when debugMem:
@@ -127,7 +127,6 @@ proc reallocate*(self: PeonGC, p: pointer, oldSize: int, newSize: int): pointer
             elif oldSize > 0 and p.isNil():
                 echo &"DEBUG - Memory manager: Warning, asked to realloc() nil pointer from {oldSize} to {newSize} bytes, ignoring request"
     except NilAccessDefect:
-        raise
         stderr.write("Peon: could not manage memory, segmentation fault\n")
         quit(139) # For now, there's not much we can do if we can't get the memory we need, so we exit
 
@@ -173,33 +172,32 @@ proc mark(self: ptr HeapObject): bool =
     return true
 
 
-proc mark(self: PeonGC): seq[ptr HeapObject] =
+proc markRoots(self: PeonGC): seq[ptr HeapObject]  =
-    ## Marks objects *not* to be
+    ## Marks root objects *not* to be
     ## collected by the GC and returns
-    ## them
+    ## their addresses
 
     # Unlike what bob does in his book,
     # we keep track of objects in a different
     # way due to how the whole thing is designed.
     # Specifically, we don't have neat structs for
-    # all peon objects 
+    # all peon objects: When we allocate() an object, 
-    # When we allocate() an object, we keep track
+    # we keep track of the small wrapper it created 
-    # of the box it created along with its type and
+    # along with its type and other metadata. Then, 
-    # other metadata, as well as the address of said
+    # we can go through the various sources of roots 
-    # box. Then, we can go through the various sources
+    # in the VM, see if they match any pointers we 
-    # of roots in the VM, see if they match any pointers
+    # already know about (we store them a hash set so 
-    # we already know about (using a hash set so it's
+    # it's really fast), and then we can be sure that 
-    # really fast), and then we can be sure that anything
+    # anything that's in the difference (i.e. mathematical
-    # that's in the difference (i.e. mathematical set difference) 
+    # set difference) between our full list of pointers
-    # between our full list of pointers and the live ones
+    # and the live ones is not a root object, so if it's not 
-    # is not a root object, so if it's not indirectly reachable
+    # indirectly reachable through a root itself, it can be 
-    # through a root itself, it can be freed. I'm not sure if I
+    # freed. I'm not sure if I can call this GC strategy precise,
-    # can call this GC strategy precise, since technically there
+    # since technically there is a chance for a regular value to 
-    # is a chance for a regular value to collide with one of the
+    # collide with one of the pointers we allocated and that would 
-    # pointers we allocated and that would cause a memory leak,
+    # cause a memory leak, but with a 64-bit address-space it probably 
-    # but with a 64-bit address-space it probably hardly matters,
+    # hardly matters, so I guess this is a mostly-precise Mark&Sweep collector
-    # so I guess this is a mostly-precise Mark&Sweep collector
+    var live = initHashSet[uint64]()
-    var live: HashSet[uint64] = initHashSet[uint64]()
     for obj in self.vm.calls:
         if obj in self.pointers:
             live.incl(obj)
@@ -217,8 +215,8 @@ proc mark(self: PeonGC): seq[ptr HeapObject] =
         if obj.mark():
             result.add(obj)
         when debugMem:
-            if result.len() > 0:
+            if obj.marked:
-                echo &"DEBUG - GC: Marking object: {result[^1][]}"
+                echo &"DEBUG - GC: Marking object: {obj[]}"
 
 
 proc trace(self: PeonGC, roots: seq[ptr HeapObject]) = 
@@ -282,7 +280,7 @@ proc collect(self: PeonGC) =
     let before = self.bytesAllocated.current
     when debugGC:
         echo "DEBUG - GC: Starting collection cycle"
-    self.trace(self.mark())
+    self.trace(self.markRoots())
     self.sweep()
     self.nextGC = self.bytesAllocated.current * HeapGrowFactor
     when debugGC:

src/main.nim

@@ -14,12 +14,23 @@
 
 ## Peon's main executable
 
+# Our stuff
+import frontend/lexer as l
+import frontend/parser as p
+import frontend/compiler as c
+import backend/vm as v
+import util/serializer as s
+import util/debugger
+import util/symbols
+import config
+
 # Builtins & external libs
 import std/strformat
 import std/strutils
 import std/terminal
 import std/parseopt
-import std/times
+when debugSerializer:
+    import std/times
 import std/os
 
 # Thanks art <3
@@ -30,15 +41,6 @@ import jale/plugin/editor_history
 import jale/keycodes
 import jale/multiline
 
-# Our stuff
-import frontend/lexer as l
-import frontend/parser as p
-import frontend/compiler as c
-import backend/vm as v
-import util/serializer as s
-import util/debugger
-import util/symbols
-import config
 
 # Forward declarations
 proc getLineEditor: LineEditor