/* Common VxWorks target definitions for GNU compiler.
Copyright (C) 2007-2017 Free Software Foundation, Inc.
Contributed by CodeSourcery, Inc.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "target.h"
#include "tree.h"
#include "stringpool.h"
#include "diagnostic-core.h"
#include "output.h"
#include "fold-const.h"
/* Like default_named_section_asm_out_constructor, except that even
constructors with DEFAULT_INIT_PRIORITY must go in a numbered
section on VxWorks. The VxWorks runtime uses a clever trick to get
the sentinel entry (-1) inserted at the beginning of the .ctors
segment. This trick will not work if we ever generate any entries
in plain .ctors sections; we must always use .ctors.PRIORITY. */
void
vxworks_asm_out_constructor (rtx symbol, int priority)
{
section *sec;
sec = get_cdtor_priority_section (priority,
/*constructor_p=*/true);
assemble_addr_to_section (symbol, sec);
}
/* See comment for vxworks_asm_out_constructor. */
void
vxworks_asm_out_destructor (rtx symbol, int priority)
{
section *sec;
sec = get_cdtor_priority_section (priority,
/*constructor_p=*/false);
assemble_addr_to_section (symbol, sec);
}
/* Return the list of FIELD_DECLs that make up an emulated TLS
variable's control object. TYPE is the structure these are fields
of and *NAME will be filled in with the structure tag that should
be used. */
static tree
vxworks_emutls_var_fields (tree type, tree *name)
{
tree field, next_field;
*name = get_identifier ("__tls_var");
field = build_decl (BUILTINS_LOCATION, FIELD_DECL,
get_identifier ("size"), unsigned_type_node);
DECL_CONTEXT (field) = type;
next_field = field;
field = build_decl (BUILTINS_LOCATION, FIELD_DECL,
get_identifier ("module_id"), unsigned_type_node);
DECL_CONTEXT (field) = type;
DECL_CHAIN (field) = next_field;
next_field = field;
/* The offset field is declared as an unsigned int with pointer mode. */
field = build_decl (BUILTINS_LOCATION, FIELD_DECL,
get_identifier ("offset"), long_unsigned_type_node);
DECL_CONTEXT (field) = type;
DECL_CHAIN (field) = next_field;
return field;
}
/* Return the CONSTRUCTOR to initialize an emulated TLS control
object. VAR is the control object. DECL is the TLS object itself
and TMPL_ADDR is the address (an ADDR_EXPR) of the initializer for
that object. */
static tree
vxworks_emutls_var_init (tree var, tree decl, tree tmpl_addr)
{
vec *v;
vec_alloc (v, 3);
tree type = TREE_TYPE (var);
tree field = TYPE_FIELDS (type);
constructor_elt elt = {field, fold_convert (TREE_TYPE (field), tmpl_addr)};
v->quick_push (elt);
field = DECL_CHAIN (field);
elt.index = field;
elt.value = build_int_cst (TREE_TYPE (field), 0);
v->quick_push (elt);
field = DECL_CHAIN (field);
elt.index = field;
elt.value = fold_convert (TREE_TYPE (field), DECL_SIZE_UNIT (decl));
v->quick_push (elt);
return build_constructor (type, v);
}
/* Do VxWorks-specific parts of TARGET_OPTION_OVERRIDE. */
void
vxworks_override_options (void)
{
/* Setup the tls emulation bits if the OS misses proper
tls support. */
targetm.have_tls = VXWORKS_HAVE_TLS;
if (!VXWORKS_HAVE_TLS)
{
targetm.emutls.get_address = "__builtin___tls_lookup";
targetm.emutls.register_common = NULL;
targetm.emutls.var_section = ".tls_vars";
targetm.emutls.tmpl_section = ".tls_data";
targetm.emutls.var_prefix = "__tls__";
targetm.emutls.tmpl_prefix = "";
targetm.emutls.var_fields = vxworks_emutls_var_fields;
targetm.emutls.var_init = vxworks_emutls_var_init;
targetm.emutls.var_align_fixed = true;
targetm.emutls.debug_form_tls_address = true;
}
/* We can use .ctors/.dtors sections only in RTP mode. */
targetm.have_ctors_dtors = TARGET_VXWORKS_RTP;
/* PIC is only supported for RTPs. */
if (flag_pic && !TARGET_VXWORKS_RTP)
error ("PIC is only supported for RTPs");
/* Default to strict dwarf-2 to prevent potential difficulties observed with
non-gdb debuggers on extensions > 2. */
if (!global_options_set.x_dwarf_strict)
dwarf_strict = 1;
if (!global_options_set.x_dwarf_version)
dwarf_version = 2;
}