sparc.c (sparc_option_override): If not set by the user, force flag_ira_share_save_slots to 0.

	* config/sparc/sparc.c (sparc_option_override): If not set by the user,
	force flag_ira_share_save_slots to 0.

From-SVN: r174148

gcc/ChangeLog

 2011-05-24  Eric Botcazou  <ebotcazou@adacore.com>
 
+	* config/sparc/sparc.c (sparc_option_override): If not set by the user,
+	force flag_ira_share_save_slots to 0.
+
+2011-05-24  Eric Botcazou  <ebotcazou@adacore.com>
+
 	* var-tracking.c (compute_cfa_pointer): Adjust head comment.
 	(vt_initialize): Set PROLOGUE_BB unconditionally.
 	Add block comment about CFA_BASE_RTX machinery.

gcc/config/sparc/sparc.c

@@ -933,6 +933,12 @@ sparc_option_override (void)
 			  ? 64 : 32),
 			 global_options.x_param_values,
 			 global_options_set.x_param_values);
+
+  /* Disable save slot sharing for call-clobbered registers by default.
+     The IRA sharing algorithm works on single registers only and this
+     pessimizes for double floating-point registers.  */
+  if (!global_options_set.x_flag_ira_share_save_slots)
+    flag_ira_share_save_slots = 0;
 }
 
 /* Miscellaneous utilities.  */