updating qsort benchmark for issue #562

Author: JeffBezanson

test/perf/perf.jl

@@ -62,9 +62,31 @@ mandelperf() = [ mandel(complex(r,i)) | r=-2.0:.1:0.5, i=-1.:.1:1. ]
 
 ## numeric vector sort ##
 
+function qsort_kernel(a, lo, hi)
+    i = lo
+    j = hi
+    while i < hi
+        pivot = a[ifloor((lo+hi)/2)]
+    	while i <= j
+            while a[i] < pivot; i = i + 1; end
+            while a[j] > pivot; j = j - 1; end
+            if i <= j
+	      	t = a[i]
+	    	a[i] = a[j]
+	    	a[j] = t
+            	i = i + 1
+            	j = j - 1
+            end
+    	end
+        if lo < j; qsort_kernel(a, lo, j); end
+        lo = i
+	j = hi
+    end
+    return a
+end
+
 function sortperf(n)
-  v = rand(n)
-  sort!(v)
+    qsort_kernel(rand(n), 1, n)
 end
 @assert issorted(sortperf(5000))
 @timeit sortperf(5000) "quicksort"