------- Comment #7 from ubizjak at gmail dot com 2008-05-05 10:53 -------
validate_unshare_change was introduced by:
2007-06-26 Jan Hubicka <[EMAIL PROTECTED]>
* fwprop.c (try_fwprop_subst): Use validate_unshare_change.
* postreload.c (reload_cse_simplify_set): Instead of copying the rtx
early use validate_unshare_change.
(reload_combine): Likewise.
* recog.c (change_t): New field unshare.
(validate_change_1): Rename from validate_change; add argument unshare.
(validate_change): Turn into wrapper of validate_change_1; update
prototype for bools.
(validate_unshare_change): New.
(confirm_change_group): Unshare changes if asked for; avoid unnecesary
calls of df_insn_rescan.
* recog.h (validate_change): Replace ints by bools.
(validate_unshare_change): Declare.
The problem is, that validate_unshare_change logic creates sharing violation if
the same RTX is propagated into two places in the same insn pattern.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36111
