feat(gnovm): add benchmark system (gnolang#1624)

I was attempting some changes with performance ramifications and wanted
to measure their impact. Eventually, they turned out to be bad
performance-wise, but the code I made for measuring performance is
probably still useful.

This PR sets up a basic performance measurement system for the GnoVM. It
leverages Go's existing benchmarking system together with templates. It
allows us to measure impact on performance using standard go tools like
[benchstat](https://pkg.go.dev/golang.org/x/perf/cmd/benchstat).

```console
$ go test -bench . -run NONE .
goos: linux
goarch: amd64
pkg: github.com/gnolang/gno/gnovm/pkg/gnolang
cpu: AMD Ryzen 7 PRO 4750U with Radeon Graphics
BenchmarkPreprocess-16                      7737            152430 ns/op
BenchmarkBenchdata/fib.gno_param:4-16              47374             24664 ns/op
BenchmarkBenchdata/fib.gno_param:8-16              10000            213632 ns/op
BenchmarkBenchdata/fib.gno_param:16-16               100          10590462 ns/op
BenchmarkBenchdata/loop.gno-16                   2556032               509.3 ns/op
BenchmarkBenchdata/matrix_mult.gno_param:3-16       1976            590535 ns/op
BenchmarkBenchdata/matrix_mult.gno_param:4-16        740           1703166 ns/op
BenchmarkBenchdata/matrix_mult.gno_param:5-16        180           6797221 ns/op
BenchmarkBenchdata/matrix_mult.gno_param:6-16         36          34389320 ns/op
BenchmarkCreateNewMachine-16                       80518             13819 ns/op
PASS
ok      github.com/gnolang/gno/gnovm/pkg/gnolang        16.790s
```

A few benchmarks are provided to show its functioning and benchmark some
initial functions. `loop.gno` brings over the `LoopyMain` existing
benchmark, and makes its output more useful by correlating it with
`b.N`.

Making this to have a preliminary review and open up discussions:

- I removed `go_bench_data.go`, because as the name suggests it tests
out things in Go and isn't actually at all related to the GnoVM.
- Do we want to keep these benchmarks in `misc/` or somewhere? Or has
the information gathered from these tests already been used to act, and
as such they can be removed?
- Was something similar already in the works? @deelawn
@petar-dambovaliev
- Is it OK to place the benchmarking files in `benchdata`, or would we
prefer another location?
- Would these benchmarks be automatically picked up for
gnolang/benchmarks? cc/ @ajnavarro @albttx

gnovm/pkg/gnolang/benchdata/fib.gno

@@ -0,0 +1,16 @@
+// param: 4 8 16
+
+package main
+
+func main() {
+	for i := 0; i < {{ .N }}; i++ {
+		fib({{ .Param }})
+	}
+}
+
+func fib(n int) int {
+	if n < 2 {
+		return 1
+	}
+	return fib(n-1) + fib(n-2)
+}

gnovm/pkg/gnolang/benchdata/loop.gno

@@ -0,0 +1,5 @@
+package main
+
+func main() {
+	for i := 0; i < {{ .N }}; i++ {}
+}

gnovm/pkg/gnolang/benchdata/matrix.gno

@@ -0,0 +1,90 @@
+// param: 3 4 5 6
+
+package main
+
+func main() {
+	const p = {{ .Param }}
+	for i := 0; i < {{ .N }}; i++ {
+		_ = det(mul(dist(p), mul(id(p), dist(p))))
+	}
+}
+
+// identity matrix
+func id(sz int) [][]int {
+	r := make([][]int, sz)
+	for i := range r {
+		r[i] = make([]int, sz)
+		r[i][i] = 1
+	}
+	return r
+}
+
+// distance from corner
+func dist(sz int) [][]int {
+	half := sz / 2
+	r := make([][]int, sz)
+	for i := range r {
+		r[i] = make([]int, sz)
+		vdist := i
+		if vdist >= half {
+			vdist = sz - 1 - i
+		}
+		for j := range r[i] {
+			hdist := j
+			if hdist >= half {
+				hdist = sz - 1 - j
+			}
+			r[i][j] = vdist + hdist
+		}
+	}
+	return r
+}
+
+func det(m [][]int) int {
+    size := len(m)
+    if size == 2 {
+        return m[0][0]*m[1][1] - m[0][1]*m[1][0]
+    }
+	subMatrix := make([][]int, size-1)
+	for j := range subMatrix {
+		subMatrix[j] = make([]int, size-1)
+	}
+
+    determinant := 0
+    for i := 0; i < size; i++ {
+        for j := 1; j < size; j++ {
+            t := 0
+            for k := 0; k < size; k++ {
+                if k == i {
+                    continue
+                }
+                subMatrix[j-1][t] = m[j][k]
+                t++
+            }
+        }
+		sign := 1
+		if i % 2 == 1 {
+			sign = -1
+		}
+        determinant += m[0][i] * det(subMatrix) * sign
+    }
+    return determinant
+}
+
+func mul(m1, m2 [][]int) [][]int {
+	size := len(m1)
+	result := make([][]int, size)
+	for i := range result {
+		result[i] = make([]int, size)
+	}
+
+	for i := 0; i < size; i++ {
+		for j := 0; j < size; j++ {
+			for k := 0; k < size; k++ {
+				result[i][j] += m1[i][k] * m2[k][j]
+			}
+		}
+	}
+
+	return result
+}

gnovm/pkg/gnolang/gno_test.go

@@ -3,12 +3,18 @@ package gnolang
 import (
 	"bytes"
 	"fmt"
+	"io"
+	"os"
+	"path/filepath"
 	"reflect"
+	"strings"
 	"testing"
+	"text/template"
 	"unsafe"
 
 	// "github.com/davecgh/go-spew/spew"
 	"github.com/jaekwon/testify/assert"
+	"github.com/jaekwon/testify/require"
 )
 
 // run empty main().
@@ -192,43 +198,84 @@ func main() {
 // Benchmarks
 
 func BenchmarkPreprocess(b *testing.B) {
-	for i := 0; i < b.N; i++ {
-		// stop timer
-		b.StopTimer()
-		pkg := &PackageNode{
-			PkgName: "main",
-			PkgPath: ".main",
-			FileSet: nil,
-		}
-		pkg.InitStaticBlock(pkg, nil)
-		main := FuncD("main", nil, nil, Ss(
-			A("mx", ":=", "1000000"),
-			For(
-				A("i", ":=", "0"),
-				X("i < mx"),
-				Inc("i"),
-			),
-		))
-		b.StartTimer()
-		// timer started
-		main = Preprocess(nil, pkg, main).(*FuncDecl)
+	pkg := &PackageNode{
+		PkgName: "main",
+		PkgPath: ".main",
+		FileSet: nil,
 	}
-}
-
-func BenchmarkLoopyMain(b *testing.B) {
-	m := NewMachine("test", nil)
+	pkg.InitStaticBlock(pkg, nil)
 	main := FuncD("main", nil, nil, Ss(
-		A("mx", ":=", "10000000"),
+		A("mx", ":=", "1000000"),
 		For(
 			A("i", ":=", "0"),
-			// X("i < 10000000"),
 			X("i < mx"),
 			Inc("i"),
 		),
 	))
-	m.RunDeclaration(main)
+	copies := make([]*FuncDecl, b.N)
+	for i := 0; i < b.N; i++ {
+		copies[i] = main.Copy().(*FuncDecl)
+	}
+	b.ResetTimer()
+
 	for i := 0; i < b.N; i++ {
-		m.RunMain()
+		main = Preprocess(nil, pkg, copies[i]).(*FuncDecl)
+	}
+}
+
+type bdataParams struct {
+	N     int
+	Param string
+}
+
+func BenchmarkBenchdata(b *testing.B) {
+	const bdDir = "./benchdata"
+	files, err := os.ReadDir(bdDir)
+	require.NoError(b, err)
+	for _, file := range files {
+		// Read file and parse template.
+		bcont, err := os.ReadFile(filepath.Join(bdDir, file.Name()))
+		cont := string(bcont)
+		require.NoError(b, err)
+		tpl, err := template.New("").Parse(cont)
+		require.NoError(b, err)
+
+		// Determine parameters.
+		const paramString = "// param: "
+		var params []string
+		pos := strings.Index(cont, paramString)
+		if pos >= 0 {
+			paramsRaw := strings.SplitN(cont[pos+len(paramString):], "\n", 2)[0]
+			params = strings.Fields(paramsRaw)
+		} else {
+			params = []string{""}
+		}
+
+		for _, param := range params {
+			name := file.Name()
+			if param != "" {
+				name += "_param:" + param
+			}
+			b.Run(name, func(b *testing.B) {
+				// Gen template with N and param.
+				var buf bytes.Buffer
+				require.NoError(b, tpl.Execute(&buf, bdataParams{
+					N:     b.N,
+					Param: param,
+				}))
+
+				// Set up machine.
+				m := NewMachineWithOptions(MachineOptions{
+					PkgPath: "main",
+					Output:  io.Discard,
+				})
+				n := MustParseFile("main.go", buf.String())
+				m.RunFiles(n)
+
+				b.ResetTimer()
+				m.RunMain()
+			})
+		}
 	}
 }