& vs new

result.txt

BenchmarkNewV1Arr-8     2000000000               1.86 ns/op
BenchmarkNewV1Struct-8  1000000000               2.04 ns/op
BenchmarkNewV2Arr-8     1000000000               3.18 ns/op
BenchmarkNewV2Struct-8  500000000                3.24 ns/op

vec2.go

package math

import (
	//"fmt"
	//"math"
)

type Vec2 [4]float32

type Vec22 struct {
	x, y, z, w float32
}

func NewV1Vec2Arr(x, y float32) *Vec2 {
	vec2 := new(Vec2)

	vec2[0], vec2[1] = x, y

	return vec2
}

func NewV1Vec2Struct(x, y float32) *Vec22 {
	vec2 := new(Vec22)

	vec2.x, vec2.y = x, y

	return vec2
}

func NewV2Vec2Arr(x, y float32) *Vec2 {
	return &Vec2{x, y}
}

func NewV2Vec2Struct(x, y float32) *Vec22 {
	return &Vec22{x:x, y:y}
}

vec2_test.go

package math

import "testing"

func BenchmarkNewV1Arr(b *testing.B) {
	for i := 0; i < b.N; i++ {
		_ = NewV1Vec2Arr(1, 4)
	}
}

func BenchmarkNewV1Struct(b *testing.B) {
	for i := 0; i < b.N; i++ {
		_ = NewV1Vec2Struct(1, 4)
	}
}

func BenchmarkNewV2Arr(b *testing.B) {
	for i := 0; i < b.N; i++ {
		_ = NewV2Vec2Arr(1, 4)
	}
}

func BenchmarkNewV2Struct(b *testing.B) {
	for i := 0; i < b.N; i++ {
		_ = NewV2Vec2Struct(1, 4)
	}
}