From patchwork Thu Dec  6 20:15:26 2012
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Subject: [rs6000] Update default loop peel limits
From: Pat Haugen <pthaugen@linux.vnet.ibm.com>
X-Patchwork-Id: 204311
Message-Id: <50C0FCDE.5010508@linux.vnet.ibm.com>
To: GCC Patches <gcc-patches@gcc.gnu.org>
Cc: David Edelsohn <dje.gcc@gmail.com>
Date: Thu, 06 Dec 2012 14:15:26 -0600

The following patch restores the old default limits for loop peeling 
that were recently changed to 100 and caused a 20% degradation in 
454.calculix.

Bootstrap/regtest on powerpc64-linux with no new regressions. Ok for trunk?

-Pat


2012-12-06  Pat Haugen <pthaugen@us.ibm.com>
         * config/rs6000/rs6000.c (rs6000_option_override_internal): Set
         default loop peeling limits.


Index: gcc/config/rs6000/rs6000.c
===================================================================
--- gcc/config/rs6000/rs6000.c	(revision 194260)
+++ gcc/config/rs6000/rs6000.c	(working copy)
@@ -3120,6 +3120,14 @@ rs6000_option_override_internal (bool gl
 			     global_options.x_param_values,
 			     global_options_set.x_param_values);
 
+      /* Increase loop peeling limits based on performance analysis. */
+      maybe_set_param_value (PARAM_MAX_PEELED_INSNS, 400,
+			     global_options.x_param_values,
+			     global_options_set.x_param_values);
+      maybe_set_param_value (PARAM_MAX_COMPLETELY_PEELED_INSNS, 400,
+			     global_options.x_param_values,
+			     global_options_set.x_param_values);
+
       /* If using typedef char *va_list, signal that
 	 __builtin_va_start (&ap, 0) can be optimized to
 	 ap = __builtin_next_arg (0).  */