re PR bootstrap/51725 (segfault in stage 3 when compiling gcc/opts.c for sparc64...

re PR bootstrap/51725 (segfault in stage 3 when compiling gcc/opts.c for sparc64-linux)

PR bootstrap/51725
* cselib.c (new_elt_loc_list): Promote addr_list to canonical node.
Add canonical node to containing_mem chain after the non-canonical
one, even if there weren't any locs to propagate.
(remove_useless_values): Keep only canonical values.
(add_mem_for_addr, cselib_lookup_mem): Canonicalize addr.
(cselib_invalidate_mem): Likewise.  Ensure v is canonical, and
canonicalize mem_chain elements that are not discarded.

From-SVN: r182982