gdb/

gdb/
	Implement basic support for DW_TAG_GNU_call_site.
	* block.c: Include gdbtypes.h and exceptions.h.
	(call_site_for_pc): New function.
	* block.h (call_site_for_pc): New declaration.
	* defs.h: Include hashtab.h.
	(make_cleanup_htab_delete, core_addr_hash, core_addr_eq): New
	declarations.
	* dwarf2-frame.c (dwarf2_frame_ctx_funcs): Install
	ctx_no_push_dwarf_reg_entry_value.
	* dwarf2expr.c (read_uleb128, read_sleb128): Support R as NULL.
	(dwarf_block_to_dwarf_reg): New function.
	(execute_stack_op) <DW_OP_GNU_entry_value>: Implement it.
	(ctx_no_push_dwarf_reg_entry_value): New function.
	* dwarf2expr.h (struct dwarf_expr_context_funcs): New field
	push_dwarf_reg_entry_value.
	(ctx_no_push_dwarf_reg_entry_value, dwarf_block_to_dwarf_reg): New
	declarations.
	* dwarf2loc.c: Include gdbcmd.h.
	(dwarf_expr_ctx_funcs): New forward declaration.
	(entry_values_debug, show_entry_values_debug, call_site_to_target_addr)
	(dwarf_expr_reg_to_entry_parameter)
	(dwarf_expr_push_dwarf_reg_entry_value): New.
	(dwarf_expr_ctx_funcs): Install dwarf_expr_push_dwarf_reg_entry_value.
	(dwarf2_evaluate_loc_desc_full): Handle NO_ENTRY_VALUE_ERROR.
	(needs_dwarf_reg_entry_value): New function.
	(needs_frame_ctx_funcs): Install it.
	(_initialize_dwarf2loc): New function.
	* dwarf2loc.h (entry_values_debug): New declaration.
	* dwarf2read.c (struct dwarf2_cu): New field call_site_htab.
	(read_call_site_scope): New forward declaration.
	(process_full_comp_unit): Copy call_site_htab.
	(process_die): Support DW_TAG_GNU_call_site.
	(read_call_site_scope): New function.
	(dwarf2_get_pc_bounds): Support NULL HIGHPC.
	(dwarf_tag_name): Support DW_TAG_GNU_call_site.
	(cleanup_htab): Delete.
	(write_psymtabs_to_index): Use make_cleanup_htab_delete instead of it.
	* exceptions.h (enum errors): New NO_ENTRY_VALUE_ERROR.
	* gdb-gdb.py (StructMainTypePrettyPrinter): Support
	FIELD_LOC_KIND_DWARF_BLOCK.
	* gdbtypes.h (enum field_loc_kind): New entry
	FIELD_LOC_KIND_DWARF_BLOCK.
	(struct main_type): New loc entry dwarf_block.
	(struct call_site, FIELD_DWARF_BLOCK, SET_FIELD_DWARF_BLOCK)
	(TYPE_FIELD_DWARF_BLOCK): New.
	* python/py-type.c: Include dwarf2loc.h.
	(check_types_equal): Support FIELD_LOC_KIND_DWARF_BLOCK.  New
	internal_error call on unknown FIELD_LOC_KIND.
	* symtab.h (struct symtab): New field call_site_htab.
	* utils.c (do_htab_delete_cleanup, make_cleanup_htab_delete)
	(core_addr_hash, core_addr_eq): New functions.

gdb/testsuite/
	Implement basic support for DW_TAG_GNU_call_site.
	* gdb.arch/Makefile.in (EXECUTABLES): Add amd64-entry-value.
	* gdb.arch/amd64-entry-value.cc: New file.
	* gdb.arch/amd64-entry-value.exp: New file.