* final.c (SEEN_BB, SEEN_NOTE, SEEN_EMITTED): Define.
(final_scan_insn): Update to take an additional SEEN argument. Emit
a line note after the prologue. Make static.
(line_note_exists): Remove.
(final): Don't initialize line_note_exists. Update call to
final_scan_insn.
* output.h (final_scan_insn): Remove prologue.
* function.c (set_insn_locators): Update comment.
(thread_prologue_and_epilogue_insns): Add a comment.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@76060 138bc75d-0d04-0410-961f-82ee72b054a4