Remove global call sets: cfgcleanup.c

old_insns_match_p just tests whether two instructions are
similar enough to merge.  With insn_callee_abi it makes more
sense to compare the ABIs directly.

2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* cfgcleanup.c (old_insns_match_p): Compare the ABIs of calls
	instead of the call-clobbered sets.

From-SVN: r276314

gcc/ChangeLog

 2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>
 
+	* cfgcleanup.c (old_insns_match_p): Compare the ABIs of calls
+	instead of the call-clobbered sets.
+
+2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>
+
 	* caller-save.c (setup_save_areas): Remove redundant |s of
 	fixed_reg_set.
 	(save_call_clobbered_regs): Likewise.  Use the call ABI rather

gcc/cfgcleanup.c

@@ -1227,13 +1227,7 @@ old_insns_match_p (int mode ATTRIBUTE_UNUSED, rtx_insn *i1, rtx_insn *i2)
 	    }
 	}
 
-      HARD_REG_SET i1_used = insn_callee_abi (i1).full_reg_clobbers ();
-      HARD_REG_SET i2_used = insn_callee_abi (i2).full_reg_clobbers ();
-      /* ??? This preserves traditional behavior; it might not be needed.  */
-      i1_used |= fixed_reg_set;
-      i2_used |= fixed_reg_set;
-
-      if (i1_used != i2_used)
+      if (insn_callee_abi (i1) != insn_callee_abi (i2))
         return dir_none;
     }