This patch restructures how the prologues/epilogues are inserted. Sibcalls
that run without prologue are now handled in shrink-wrap.c; it communicates
what is already handled by setting the EDGE_IGNORE flag. The
try_shrink_wrapping function then doesn't need to be passed the bb_flags
anymore.
* function.c (make_epilogue_seq): Remove epilogue_end parameter.
(thread_prologue_and_epilogue_insns): Remove bb_flags. Restructure
code. Ignore sibcalls on EDGE_IGNORE edges.
* shrink-wrap.c (handle_simple_exit): New function. Set EDGE_IGNORE
on edges for sibcalls that run without prologue. The rest of the
function is combined from...
(fix_fake_fallthrough_edge): ... this, and ...
(try_shrink_wrapping): ... a part of this. Remove the bb_with
function argument, make it a local variable.
From-SVN: r236491
