Fixed issue with resuming from incremental compilation

src/backend/vm.nim

@@ -220,7 +220,7 @@ proc markRoots(self: var PeonVM): HashSet[ptr HeapObject] =
             result.incl(obj)
     for obj in self.operands:
         if obj in self.gc.pointers:
-            result.incl(obj)
+            result.incl(obj)        
     var obj: ptr HeapObject
     for p in result:
         obj = cast[ptr HeapObject](p)
@@ -1063,14 +1063,13 @@ proc run*(self: var PeonVM, chunk: Chunk, breakpoints: seq[uint64] = @[], repl:
 proc resume*(self: var PeonVM, chunk: Chunk) =
     ## Resumes execution of the given chunk (which
     ## may have changed since the last call to run()).
-    ## The instruction pointer is set to address 12,
-    ## as it is assumed that the compiler has produced
-    ## new code in the chunk, replacing the previous one.
     ## No other state mutation occurs and all stacks as 
-    ## well as other metadata are left intact
+    ## well as other metadata are left intact. This should
+    ## not be used directly unless you know what you're
+    ## doing, as incremental compilation support is very
+    ## experimental and highly unstable
+    self.chunk = chunk
     try:
-        self.ip = 12
-        self.chunk = chunk
         self.dispatch()
     except NilAccessDefect:
         stderr.writeLine("Memory Access Violation: SIGSEGV")

src/frontend/compiler/targets/bytecode/target.nim

@@ -1981,12 +1981,12 @@ proc funDecl(self: BytecodeCompiler, node: FunDecl, name: Name) =
             self.patchJump(jump)
         self.endScope()
         # Terminates the function's context
+        let stop = self.chunk.code.len().toTriple()
         self.emitByte(OpCode.Return, self.peek().token.line)
         if hasVal:
             self.emitByte(1, self.peek().token.line)
         else:
             self.emitByte(0, self.peek().token.line)
-        let stop = self.chunk.code.len().toTriple()
         self.chunk.functions[idx] = stop[0]
         self.chunk.functions[idx + 1] = stop[1]
         self.chunk.functions[idx + 2] = stop[2]

src/main.nim

@@ -58,7 +58,7 @@ proc repl(warnings: seq[WarningKind] = @[], mismatches: bool = false, mode: Comp
         tokens: seq[Token] = @[]
         tree: seq[Declaration] = @[]
         compiler = newBytecodeCompiler(replMode=true)
-        compiled: Chunk
+        compiled: Chunk = newChunk()
         serialized: Serialized
         tokenizer = newLexer()
         vm = newPeonVM()
@@ -104,7 +104,7 @@ proc repl(warnings: seq[WarningKind] = @[], mismatches: bool = false, mode: Comp
                 for node in tree:
                     styledEcho fgGreen, "\t", $node
                 echo ""
-            compiled = compiler.compile(tree, "stdin", tokenizer.getLines(), input, showMismatches=mismatches, disabledWarnings=warnings, mode=mode)
+            compiled = compiler.compile(tree, "stdin", tokenizer.getLines(), input, chunk=compiled, showMismatches=mismatches, disabledWarnings=warnings, mode=mode, incremental=true)
             when debugCompiler:
                 styledEcho fgCyan, "Compilation step:\n"
                 debugger.disassembleChunk(compiled, "stdin")

src/peon/stdlib/std.pn

@@ -16,4 +16,9 @@ export comparisons;
 
 var version* = 1;
 var _private = 5;  # Invisible outside the module (underscore is to silence warning)
-var test* = 0x60;
+var test* = 0x60;
+
+
+fn testGlobals*: bool {
+    return version == 1 and _private == 5 and test == 0x60;
+}