small changes

profile.go

@@ -0,0 +1,61 @@
+//go:build ignore
+
+package main
+
+import (
+	"monkey/internal/compiler"
+	"monkey/internal/parser"
+	"monkey/internal/vm"
+	"os"
+	"runtime/pprof"
+)
+
+const fib = `
+fib := fn(n) {
+	if (n < 2) {
+		return n
+	}
+	return fib(n-1) + fib(n-2)
+}
+
+print(fib(35))`
+
+func check(err error) {
+	if err != nil {
+		panic(err)
+	}
+}
+
+func code(path string) string {
+	b, err := os.ReadFile(path)
+	check(err)
+
+	return string(b)
+}
+
+func fileOrDefault() string {
+	if len(os.Args) > 1 {
+		return code(os.Args[1])
+	}
+	return fib
+}
+
+func main() {
+	cpuf, err := os.Create("cpu.prof")
+	check(err)
+
+	code := fileOrDefault()
+	tree, errs := parser.Parse("<profiler>", code)
+	if len(errs) > 0 {
+		panic("parser errors")
+	}
+
+	c := compiler.New()
+	c.SetFileInfo("<profiler>", code)
+	check(c.Compile(tree))
+
+	check(pprof.StartCPUProfile(cpuf))
+	defer pprof.StopCPUProfile()
+	mvm := vm.New("<profiler>", c.Bytecode())
+	mvm.Run()
+}