Fix and test recursive functions with fibonacci numbers

fib.gi

@@ -0,0 +1,17 @@
+//#!/usr/bin/env gi
+
+package main
+
+// Compute fibonacci numbers, no memoization
+func fib(n int) int {
+	if n < 2 {
+		return n
+	}
+	return fib(n-2) + fib(n-1)
+}
+
+func main() {
+	println(fib(35))
+	//println(fib(10))
+}
+

interp/cfg.go

@@ -73,6 +73,8 @@ func (e *Node) Cfg(i *Interpreter) int {
 				n.run = equal
 			case token.LSS:
 				n.run = lower
+			case token.SUB:
+				n.run = sub
 			}
 			maxIndex++
 			n.findex = maxIndex

interp/interp.go

@@ -82,10 +82,9 @@ func (i *Interpreter) Eval(src string) interface{} {
 	if i.opt.Cfg {
 		root.CfgDot(Dotty())
 	}
+	//root.OptimCfg()
 
 	// Execute CFG
-	entry := root.Child[1] // FIXME: entry point should be resolved from 'main' name
-	//entry.OptimCfg()
-	Run(entry, nil, nil, nil)
+	Run(i.def["main"], nil, nil, nil)
 	return i.out
 }

interp/run.go

@@ -4,6 +4,7 @@ import "fmt"
 
 // Run a Go function
 func Run(def *Node, cf *Frame, args []*Node, rets []int) {
+	//fmt.Println("run", def.Child[0].ident)
 	// Allocate a new Frame to store local variables
 	f := Frame(make([]interface{}, def.findex))
 
@@ -12,6 +13,7 @@ func Run(def *Node, cf *Frame, args []*Node, rets []int) {
 	for i, arg := range args {
 		f[param[i].findex] = value(arg, cf)
 	}
+	//fmt.Println("frame:", f)
 
 	// Execute by walking the CFG and running node func at each step
 	body := def.Child[2]
@@ -56,6 +58,7 @@ func printa(n []*Node, f *Frame) {
 }
 
 func (interp *Interpreter) call(n *Node, f *Frame) {
+	//fmt.Println("call", n.Child[0].ident)
 	if n.Child[0].ident == "println" {
 		printa(n.Child[1:], f)
 		return
@@ -81,6 +84,10 @@ func add(n *Node, f *Frame) {
 	(*f)[n.findex] = value(n.Child[0], f).(int64) + value(n.Child[1], f).(int64)
 }
 
+func sub(n *Node, f *Frame) {
+	(*f)[n.findex] = value(n.Child[0], f).(int64) - value(n.Child[1], f).(int64)
+}
+
 func equal(n *Node, f *Frame) {
 	(*f)[n.findex] = value(n.Child[0], f).(int64) == value(n.Child[1], f).(int64)
 }
@@ -99,4 +106,6 @@ func _return(n *Node, f *Frame) {
 	for i, c := range n.Child {
 		(*f)[i] = (*f)[c.findex]
 	}
+	// FIXME: should be done during compiling, not run
+	n.tnext = nil
 }