diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 281540f416f..7c1030c5bf1 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2012-09-10  Richard Sandiford  <rdsandiford@googlemail.com>
+
+	* ira.c (setup_pressure_classes): Handle synonymous classes.
+
 2012-09-10  Marc Glisse  <marc.glisse@inria.fr>
 
         * tree-ssa-forwprop.c (simplify_bitfield_ref): New function.
diff --git a/gcc/ira.c b/gcc/ira.c
index 691614e8d5a..ad0ae0a8e6e 100644
--- a/gcc/ira.c
+++ b/gcc/ira.c
@@ -789,7 +789,7 @@ setup_pressure_classes (void)
 	     hard registers and movement between them is costly
 	     (e.g. SPARC FPCC registers).  We still should consider it
 	     as a candidate for a pressure class.  */
-	  && alloc_reg_class_subclasses[cl][0] != LIM_REG_CLASSES)
+	  && alloc_reg_class_subclasses[cl][0] < cl)
 	{
 	  /* Check that the moves between any hard registers of the
 	     current class are not more expensive for a legal mode