middle-end/111422 - wrong stack var coalescing, handle PHIs

The gcc.c-torture/execute/pr111422.c testcase after installing the
sink pass improvement reveals that we also need to handle

 _65 = &g + _58;              _44 = &g + _43;
 # _59 = PHI <_65, _44>
 *_59 = 8;
 g = {v} {CLOBBER(eos)};
 ...
 n[0] = &f;
 *_59 = 8;
 g = {v} {CLOBBER(eos)};

where we fail to see the conflict between n and g after the first
clobber of g.  Before the sinking improvement there was a conflict
recorded on a path where _65/_44 are unused, so the real conflict
was missed but the fake one avoided the miscompile.

The following handles PHI defs in add_scope_conflicts_2 which
fixes the issue.

	PR middle-end/111422
	* cfgexpand.cc (add_scope_conflicts_2): Handle PHIs
	by recursing to their arguments.

0 files changed, 0 insertions, 0 deletions