panic benchmark

main_test.go

package main

import (
	"errors"
	"fmt"
	"math"
	"testing"
)

var ErrDivideByZero error = errors.New("can't divide by zero")

const MaxIters = 1000

func BenchmarkDivide(b *testing.B) {
	p1, p2 := 10000, 2000

	callDivide := func(a, b int) int {
		acc := 0
		for j := 0; j < MaxIters; j++ {
			acc += Divide(a+j, b-j)
		}
		return acc
	}

	for i := 0; i < b.N; i++ {
		callDivide(p1, p2)
	}
}

func BenchmarkDivide2(b *testing.B) {
	p1, p2 := 10000, 2000

	callDivide := func(a, b int) int {
		acc := 0
		for j := 0; j < MaxIters; j++ {
			r, _ := Divide2(a+j, b-j)
			acc += r
		}
		return acc
	}

	for i := 0; i < b.N; i++ {
		callDivide(p1, p2)

	}
}

func BenchmarkDivide2Check(b *testing.B) {
	p1, p2 := 10000, 2000

	callDivide := func(a, b int) int {
		acc := 0
		for j := 0; j < MaxIters; j++ {
			r, err := Divide2(a+j, b-j)
			if err == nil {
				acc += r
			}
		}
		return acc
	}

	for i := 0; i < b.N; i++ {
		callDivide(p1, p2)
	}
}

func BenchmarkPanic(b *testing.B) {
	p1, p2 := 10000, 2000

	callDivide := func(a, b int) int {
		acc := 0
		for j := 0; j < MaxIters; j++ {
			acc += Divide(a+j, b-j)
		}
		return acc
	}

	for i := 0; i < b.N; i++ {
		callDivide(p1, p2)
	}
}
func BenchmarkPanicRecover(b *testing.B) {
	p1, p2 := 10000, 2000

	callDivide := func(a, b int) int {
		defer func() {
			if r := recover(); r != nil {
				fmt.Println("error")
			}
		}()

		acc := 0
		for j := 0; j < MaxIters; j++ {
			acc += Divide(a+j, b-j)
		}
		return acc
	}

	for i := 0; i < b.N; i++ {
		callDivide(p1, p2)
	}
}

//go:noinline
func Divide(a, b int) int {
	if b == 0 || math.Abs(float64(b)) > math.Abs(float64(a)) {
		return 0
	}
	return a / b
}

//go:noinline
func Divide2(a, b int) (int, error) {
	if b == 0 || math.Abs(float64(b)) > math.Abs(float64(a)) {
		return 0, ErrDivideByZero
	}
	return a / b, nil
}

//go:noinline
func DividePanic(a, b int) int {
	if b == 0 || math.Abs(float64(b)) > math.Abs(float64(a)) {
		panic(ErrDivideByZero)
	}
	return a / b
}