alias.c (init_alias_analysis): Avoid self-referential value when setting…

alias.c (init_alias_analysis): Avoid self-referential value when setting reg_known_value from REG_EQUAL notes.

        * alias.c (init_alias_analysis): Avoid self-referential value
        when setting reg_known_value from REG_EQUAL notes.

From-SVN: r25211

gcc/ChangeLog

+Mon Feb 15 00:40:45 1999  J"orn Rennecke <amylaar@cygnus.co.uk>
+
+	* alias.c (init_alias_analysis): Avoid self-referential value
+	when setting reg_known_value from REG_EQUAL notes.
+
 Sun Feb 14 23:12:10 1999  Richard Henderson  <rth@cygnus.com>
 
 	* i386.c (legitimate_address_p): Verify modes of base and index.

gcc/alias.c

@@ -1465,7 +1465,8 @@ init_alias_analysis ()
 		  && (((note = find_reg_note (insn, REG_EQUAL, 0)) != 0
 		       && REG_N_SETS (REGNO (SET_DEST (set))) == 1)
 		      || (note = find_reg_note (insn, REG_EQUIV, NULL_RTX)) != 0)
-		  && GET_CODE (XEXP (note, 0)) != EXPR_LIST)
+		  && GET_CODE (XEXP (note, 0)) != EXPR_LIST
+		  && ! reg_overlap_mentioned_p (SET_DEST (set), XEXP (note, 0)))
 		{
 		  int regno = REGNO (SET_DEST (set));
 		  reg_known_value[regno] = XEXP (note, 0);