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Enable array prefetching also with -fprofile-use


Hi,
with -fprofile-use the prefetching should not be risky since we have idea about
what loops are hot and what are their average number of iterations.  So I think
we ought to enable the pass as we do with -O3.

If there will not be complains, I will commit the following tonight.
bootstrapped/regtested x86_64-linux
Honza
	* config/i386/i386.c (override_options): Enable prefetching also with
	-fprofile-use.
Index: config/i386/i386.c
===================================================================
--- config/i386/i386.c	(revision 161690)
+++ config/i386/i386.c	(working copy)
@@ -3558,7 +3558,7 @@ override_options (bool main_args_p)
   /* Enable sw prefetching at -O3 for CPUS that prefetching is helpful.  */
   if (flag_prefetch_loop_arrays < 0
       && HAVE_prefetch
-      && optimize >= 3
+      && (optimize >= 3 || flag_profile_use)
       && software_prefetching_beneficial_p ())
     flag_prefetch_loop_arrays = 1;
 


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