[Mono-bugs] [Bug 78642][Wis] Changed - Bad performance of Mono (JIT-compiler)

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Changed by vargaz at gmail.com.

http://bugzilla.ximian.com/show_bug.cgi?id=78642

--- shadow/78642	2006-06-16 06:54:50.000000000 -0400
+++ shadow/78642.tmp.32220	2006-06-16 09:14:02.000000000 -0400
@@ -336,6 +336,18 @@
 Elapsed time =3.153726
 [zag at zag Serdyuk]$ mono PerformanceTest2.exe
 Elapsed time =3.157437 
 
 That is, MS .NET outperforms Mono in more than 2,5 times 
 on this example.
+
+------- Additional Comments From vargaz at gmail.com  2006-06-16 09:14 -------
+The MS JIT is certainly better than ours, so these kinds of differences
+can be expected. Changing 'i' to be an uint improves perf on mono
+by about 30% though.
+
+Some optimizations which can be performed but we don't do it are:
+- conversion of division by / 8 into a right shift when the
+  value to be divided is known to be positive ('i' in the inner loop)
+- array bound check removal on the array accesses in the inner loop.
+
+