Better debug info for inlined functions.

Better debug info for inlined functions.

* dwarf2out.c (add_call_src_coords_attributes): New.
(gen_inlined_subroutine_die): Call it.
(maybe_emit_file, init_file_table): Add comments.
(prune_unused_types_walk_attribs): Pass DW_AT_call_file through
maybe_emit_file.
* tree-inline.c (remap_block): Copy BLOCK_SOURCE_LOCATION.
(expand_call_inline): Set BLOCK_SOURCE_LOCATION.
* tree.h (BLOCK_SOURCE_LOCATION): New.
(struct tree_block): New field locus.

From-SVN: r102379