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perf: Improve mandelbrot/1.go #489

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56 changes: 24 additions & 32 deletions bench/algorithm/mandelbrot/1.go
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Original file line number Diff line number Diff line change
Expand Up @@ -18,18 +18,17 @@ func main() {
chunk_size := size / 8
inv := 2.0 / float64(size)
xloc := make([][8]float64, chunk_size)
for i := 0; i < size; i++ {
for i := range size {
xloc[i/8][i%8] = float64(i)*inv - 1.5
}
fmt.Printf("P4\n%d %d\n", size, size)

pixels := make([]byte, size*chunk_size)
for chunk_id := 0; chunk_id < size; chunk_id++ {
for chunk_id := range size {
ci := float64(chunk_id)*inv - 1.0
offset := chunk_id * chunk_size
for i := 0; i < chunk_size; i++ {
r := mbrot8(&xloc[i], ci)
if r > 0 {
for i := range chunk_size {
if r := mbrot8(&xloc[i], ci); r > 0 {
pixels[offset+i] = r
}
}
Expand All @@ -42,14 +41,9 @@ func main() {

func mbrot8(cr *[8]float64, civ float64) byte {
ci := [8]float64{civ, civ, civ, civ, civ, civ, civ, civ}
zr := [8]float64{}
zi := [8]float64{}
tr := [8]float64{}
ti := [8]float64{}
absz := [8]float64{}
tmp := [8]float64{}
for _i := 0; _i < 10; _i++ {
for _j := 0; _j < 5; _j++ {
var zr, zi, tr, ti, absz, tmp [8]float64
for range 10 {
for range 5 {
add(&zr, &zr, &tmp)
mul(&tmp, &zi, &tmp)
add(&tmp, &ci, &zi)
Expand All @@ -61,19 +55,15 @@ func mbrot8(cr *[8]float64, civ float64) byte {
mul(&zi, &zi, &ti)
}
add(&tr, &ti, &absz)
terminate := true
for i := 0; i < 8; i++ {
if absz[i] <= 4.0 {
terminate = false
break
}
}
if terminate {
if !(absz[0] <= 4.0 || absz[1] <= 4.0 ||
absz[2] <= 4.0 || absz[3] <= 4.0 ||
absz[4] <= 4.0 || absz[5] <= 4.0 ||
absz[6] <= 4.0 || absz[7] <= 4.0) {
return 0
}
}
accu := byte(0)
for i := 0; i < 8; i++ {
for i := range 8 {
if absz[i] <= 4.0 {
accu |= byte(0x80) >> i
}
Expand All @@ -82,19 +72,21 @@ func mbrot8(cr *[8]float64, civ float64) byte {
}

func add(a, b, r *[8]float64) {
for i := 0; i < 8; i++ {
r[i] = a[i] + b[i]
}
r[0], r[1] = a[0]+b[0], a[1]+b[1]
r[2], r[3] = a[2]+b[2], a[3]+b[3]
r[4], r[5] = a[4]+b[4], a[5]+b[5]
r[6], r[7] = a[6]+b[6], a[7]+b[7]
}

func minus(a, b, r *[8]float64) {
for i := 0; i < 8; i++ {
r[i] = a[i] - b[i]
}
r[0], r[1] = a[0]-b[0], a[1]-b[1]
r[2], r[3] = a[2]-b[2], a[3]-b[3]
r[4], r[5] = a[4]-b[4], a[5]-b[5]
r[6], r[7] = a[6]-b[6], a[7]-b[7]
}

func mul(a, b, r *[8]float64) {
for i := 0; i < 8; i++ {
r[i] = a[i] * b[i]
}
r[0], r[1] = a[0]*b[0], a[1]*b[1]
r[2], r[3] = a[2]*b[2], a[3]*b[3]
r[4], r[5] = a[4]*b[4], a[5]*b[5]
r[6], r[7] = a[6]*b[6], a[7]*b[7]
}