gdb/

gdb/
	Display @entry parameter values even for references.
	* ada-valprint.c (ada_val_print_1) <TYPE_CODE_REF>: Try also
	coerce_ref_if_computed.
	* c-valprint.c (c_val_print) <TYPE_CODE_REF>: Likewise.
	* dwarf2expr.c (dwarf_block_to_dwarf_reg_deref): New function.
	(execute_stack_op) <DW_OP_GNU_entry_value>: Add -1 deref_size to the
	existing push_dwarf_reg_entry_value call.  Add new detection calling
	dwarf_block_to_dwarf_reg_deref.  Update the error message.
	(ctx_no_push_dwarf_reg_entry_value): New parameter deref_size.
	* dwarf2expr.h
	(struct dwarf_expr_context_funcs) <push_dwarf_reg_entry_value>: Add new
	parameter deref_size, describe it in the comment.
	(ctx_no_push_dwarf_reg_entry_value): Add new parameter deref_size.
	(dwarf_block_to_dwarf_reg_deref): New declaration.
	* dwarf2loc.c (dwarf_entry_parameter_to_value): Add new parameter
	deref_size, describe it in the function comment.  New variables
	data_src and size, fetch the alternative block accoring to DEREF_SIZE.
	(dwarf_expr_push_dwarf_reg_entry_value): Add new parameter deref_size,
	describe it in the function comment.  Fetch the alternative block
	accoring to DEREF_SIZE.
	(entry_data_value_coerce_ref, entry_data_value_copy_closure)
	(entry_data_value_free_closure, entry_data_value_funcs): New.
	(value_of_dwarf_reg_entry): New variables checked_type, target_type,
	outer_val, target_val, val and addr.  Try to fetch and create also
	referenced value content.
	(pieced_value_funcs): NULL value for coerce_ref.
	(needs_dwarf_reg_entry_value): Add new parameter deref_size.
	* f-valprint.c (f_val_print) <TYPE_CODE_REF>: Try also
	coerce_ref_if_computed.
	* opencl-lang.c (opencl_value_funcs): NULL value for coerce_ref.
	* p-valprint.c (pascal_val_print) <TYPE_CODE_REF>: Likewise.
	* stack.c (read_frame_arg): Compare also dereferenced values.
	* value.c (value_computed_funcs): Make the parameter v const, use
	value_lval_const for it.
	(value_lval_const, coerce_ref_if_computed): New function.
	(coerce_ref): New variable retval.  Call also coerce_ref_if_computed.
	* value.h (struct lval_funcs): New field coerce_ref.
	(value_computed_funcs): Make the parameter v const.
	(value_lval_const, coerce_ref_if_computed): New declarations.

gdb/testsuite/
	Display @entry parameter values even for references.
	* gdb.arch/amd64-entry-value.cc (reference, datap, datap_input): New
	functions.
	(main): New variables regvar, nodatavarp, stackvar1, stackvar2.  Call
	reference and datap_input.
	* gdb.arch/amd64-entry-value.exp (reference, breakhere_reference): New
	breakpoints.
	(continue to breakpoint: entry_reference: reference)
	(entry_reference: bt at entry)
	(continue to breakpoint: entry_reference: breakhere_reference)
	(entry_reference: bt, entry_reference: ptype regparam)
	(entry_reference: p regparam, entry_reference: ptype regparam@entry)
	(entry_reference: p regparam@entry, entry_reference: p &regparam@entry)
	(entry_reference: p regcopy, entry_reference: p nodataparam)
	(entry_reference: p nodataparam@entry): New tests.