The dump_* API attempts to capture emission location metadata for the
various dump messages, but looking in -fsave-optimization-record shows
that many dump messages are lacking useful impl_location values, instead
having this location within dumpfile.c:

            "impl_location": {
                "file": "../../src/gcc/dumpfile.c",
                "function": "ensure_pending_optinfo",
                "line": 1169
            },

The problem is that the auto-capturing of dump_impl_location_t is tied to
dump_location_t, and this is tied to the dump_*_loc calls.  If a message
comes from a dump_* call without a "_loc" suffix (e.g. dump_printf), the
current code synthesizes the dump_location_t within
dump_context::ensure_pending_optinfo, and thus saves the useless
impl_location seen above.

This patch fixes things by changing the dump_* API so that, rather than
taking a dump_flags_t, they take a new class dump_metadata_t, which is
constructed from a dump_flags_t, but captures the emission location.

Hence e.g.:

  dump_printf (MSG_NOTE, "some message\n");

implicitly builds a dump_metadata_t wrapping the MSG_NOTE and the
emission location.  If there are several dump_printf calls without
a dump_*_loc call, the emission location within the optinfo is that
of the first dump call within it.

The patch updates selftest::test_capture_of_dump_calls to verify
that the impl location of various dump_* calls is captured.  I also
verified things manually.

gcc/ChangeLog:
	* dump-context.h (dump_context::dump_loc): Convert 1st param from
	dump_flags_t to const dump_metadata_t &.  Convert 2nd param from
	const dump_location_t & to const dump_user_location_t &.
	(dump_context::dump_loc_immediate): Convert 2nd param from
	const dump_location_t & to const dump_user_location_t &.
	(dump_context::dump_gimple_stmt): Convert 1st param from
	dump_flags_t to const dump_metadata_t &.
	(dump_context::void dump_gimple_stmt_loc): Likewise; convert
	2nd param from const dump_location_t & to
	const dump_user_location_t &.
	(dump_context::dump_gimple_expr): Convert 1st param from
	dump_flags_t to const dump_metadata_t &.
	(dump_context::dump_gimple_expr_loc): Likewise; convert
	2nd param from const dump_location_t & to
	const dump_user_location_t &.
	(dump_context::dump_generic_expr): Convert 1st param from
	dump_flags_t to const dump_metadata_t &.
	(dump_context::dump_generic_expr_loc): Likewise; convert
	2nd param from const dump_location_t & to
	const dump_user_location_t &.
	(dump_context::dump_printf_va): Convert 1st param from
	dump_flags_t to const dump_metadata_t &.
	(dump_context::dump_printf_loc_va): Likewise; convert
	2nd param from const dump_location_t & to
	const dump_user_location_t &.
	(dump_context::dump_dec): Convert 1st param from
	dump_flags_t to const dump_metadata_t &.
	(dump_context::dump_symtab_node): Likewise.
	(dump_context::begin_scope): Split out 2nd param into
	user and impl locations.
	(dump_context::ensure_pending_optinfo): Add metadata param.
	(dump_context::begin_next_optinfo): Replace dump_location_t param
	with metadata and user location.
	* dumpfile.c (dump_context::dump_loc): Convert 1st param from
	dump_flags_t to const dump_metadata_t &.  Convert 2nd param from
	const dump_location_t & to const dump_user_location_t &.
	(dump_context::dump_loc_immediate): Convert 2nd param from
	const dump_location_t & to const dump_user_location_t &.
	(dump_context::dump_gimple_stmt): Convert 1st param from
	dump_flags_t to const dump_metadata_t &.
	(dump_context::void dump_gimple_stmt_loc): Likewise; convert
	2nd param from const dump_location_t & to
	const dump_user_location_t &.
	(dump_context::dump_gimple_expr): Convert 1st param from
	dump_flags_t to const dump_metadata_t &.
	(dump_context::dump_gimple_expr_loc): Likewise; convert
	2nd param from const dump_location_t & to
	const dump_user_location_t &.
	(dump_context::dump_generic_expr): Convert 1st param from
	dump_flags_t to const dump_metadata_t &.
	(dump_context::dump_generic_expr_loc): Likewise; convert
	2nd param from const dump_location_t & to
	const dump_user_location_t &.
	(dump_context::dump_printf_va): Convert 1st param from
	dump_flags_t to const dump_metadata_t &.
	(dump_context::dump_printf_loc_va): Likewise; convert
	2nd param from const dump_location_t & to
	const dump_user_location_t &.
	(dump_context::dump_dec): Convert 1st param from
	dump_flags_t to const dump_metadata_t &.
	(dump_context::dump_symtab_node): Likewise.
	(dump_context::begin_scope): Split out 2nd param into
	user and impl locations.
	(dump_context::ensure_pending_optinfo): Add metadata param.
	(dump_context::begin_next_optinfo): Replace dump_location_t param
	with metadata and user location.
	(dump_gimple_stmt): Convert 1st param from dump_flags_t to
	const dump_metadata_t &.
	(dump_gimple_stmt_loc): Likewise; convert 2nd param from
	const dump_location_t & to const dump_user_location_t &.
	(dump_gimple_expr): Convert 1st param from dump_flags_t to
	const dump_metadata_t &.
	(dump_gimple_expr_loc): Likewise; convert 2nd param from
	const dump_location_t & to const dump_user_location_t &.
	(dump_generic_expr): Convert 1st param from dump_flags_t to
	const dump_metadata_t &.
	(dump_generic_expr_loc): Likewise; convert 2nd param from
	const dump_location_t & to const dump_user_location_t &.
	(dump_printf): Convert 1st param from dump_flags_t to
	const dump_metadata_t &.
	(dump_printf_loc): Likewise; convert 2nd param from
	const dump_location_t & to const dump_user_location_t &.
	(dump_dec): Convert 1st param from dump_flags_t to
	const dump_metadata_t &.
	(dump_symtab_node): Likewise.
	(dump_begin_scope): Split out 2nd param into user and impl
	locations.
	(selftest::assert_impl_location_eq): New function.
	(ASSERT_IMPL_LOCATION_EQ): New macro.
	(selftest::test_impl_location): Update to use
	ASSERT_IMPL_LOCATION_EQ.
	(selftest::test_capture_of_dump_calls): Convert "loc" to
	dump_user_location_t.  Add ASSERT_IMPL_LOCATION_EQ throughout,
	verifying line numbers of dump emissions.
	* dumpfile.h (class dump_metadata_t): New class.
	(dump_printf): Convert 1st param from dump_flags_t to
	const dump_metadata_t &.
	(dump_printf_loc): Likewise; convert 2nd param from
	const dump_location_t & to const dump_user_location_t &.
	(dump_generic_expr_loc): Likewise.
	(dump_generic_expr): Convert 1st param from dump_flags_t to
	const dump_metadata_t &.
	(dump_gimple_stmt_loc): Likewise; convert 2nd param from
	const dump_location_t & to const dump_user_location_t &.
	(dump_gimple_stmt): Convert 1st param from dump_flags_t to
	const dump_metadata_t &.
	(dump_gimple_expr_loc): Likewise; convert 2nd param from
	const dump_location_t & to const dump_user_location_t &.
	(dump_gimple_expr): Convert 1st param from dump_flags_t to
	const dump_metadata_t &.
	(dump_symtab_node): Likewise.
	(dump_dec): Likewise.
	(dump_begin_scope): Split out 2nd param into user and impl
	locations.
	(auto_dump_scope::auto_dump_scope): Split "loc" param into a user
	location and impl_location, and capture the impl_location.
	(AUTO_DUMP_SCOPE): Rename param from LOC to USER_LOC.
	* loop-unroll.c (report_unroll): Update for changes to
	dump_printf_loc and dump_printf.
	* opt-problem.cc (opt_problem::opt_problem): Update for change to
	dump_loc.
	* optinfo-emit-json.cc
	(selftest::test_building_json_from_dump_calls): Convert "loc" from
	dump_location_t to dump_user_location_t.
	* optinfo.cc (optinfo::emit_for_opt_problem): Update for change in
	dump_loc_immediate.
	* profile.c (compute_branch_probabilities): Update for change to
	dump_printf_loc.
	* selftest.h (ASSERT_STR_CONTAINS_AT): New macro.
	* tree-vect-slp.c (vect_print_slp_tree): Update for change to
	dump_printf_loc.

From-SVN: r266501