Merge pull request JuliaLang#8813 from pabloferz/pf/perf

Java microbenchmark fix

test/perf/micro/java/src/main/java/Complex.java

@@ -0,0 +1,21 @@
+public class Complex {
+ private final double re;
+ private final double im;
+
+ public Complex(double real, double imag) {
+ re = real;
+ im = imag;
+ }
+
+ public static double abs(Complex z) {
+ return Math.sqrt(z.re*z.re + z.im*z.im);
+ }
+
+ public static Complex add(Complex a, Complex b) {
+ return new Complex(a.re + b.re, a.im + b.im);
+ }
+
+ public static Complex mul(Complex a, Complex b) {
+ return new Complex(a.re*b.re - a.im*b.im, a.re*b.im + a.im*b.re);
+ }
+}

test/perf/micro/java/src/main/java/PerfBLAS.java

@@ -245,32 +245,22 @@ private static double pisum() {
  return sum;
  }
 
- private static int mandel(double zReal, double zImag) {
+ private static int mandel(double re, double im) {
  int n = 0;
- double cReal = zReal;
- double cImag = zImag;
+ Complex z = new Complex(re, im);
+ Complex c = new Complex(re, im);
  for (n=0; n<=79; ++n) {
- if (complexAbs(zReal,zImag) > 2.0) {
+ if (Complex.abs(z) > 2.0) {
  n -= 1;
  break;
  }
 
- // z^2
- double zSquaredReal = zReal*zReal-zImag*zImag;
- double zSquaredImag = zReal*zImag+zImag*zReal;
-
- // +c
- zReal = zSquaredReal+cReal;
- zImag = zSquaredImag+cImag;
-
+ // z = z*z + c
+ z = Complex.add(Complex.mul(z, z), c)
  }
  return n+1;
  }
 
- private static double complexAbs(double zReal, double zImag) {
- return Math.sqrt(zReal*zReal + zImag*zImag);
- }
-
  private static int mandelperf() {
  int mandel_sum = 0;
  for (double re=-2.0; re<=0.5; re+=0.1) {