[Bug rtl-optimization/44194] struct returned by value generates useless stores

[eraman at google dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44194

--- Comment #9 from Easwaran Raman <eraman at google dot com> 2011-04-12 22:39:23 UTC ---
Created attachment 23968
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23968
Patch to dse.c to be less conservative with calls.

Currently dse kills all stores on a call since call can do a wild read. But
calls can not read off frame unless it is a local variable that can escape.
This patch ensures frame based stores are not killed on a call if they can't
escape. For the first struct return case, this removes the redundant stores to
the local variable. Does this look reasonable?