1 /* Common VxWorks target definitions for GNU compiler.
2 Copyright (C) 2007, 2008
3 Free Software Foundation, Inc.
4 Contributed by CodeSourcery, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
24 #include "coretypes.h"
31 /* Like default_named_section_asm_out_constructor, except that even
32 constructors with DEFAULT_INIT_PRIORITY must go in a numbered
33 section on VxWorks. The VxWorks runtime uses a clever trick to get
34 the sentinel entry (-1) inserted at the beginning of the .ctors
35 segment. This trick will not work if we ever generate any entries
36 in plain .ctors sections; we must always use .ctors.PRIORITY. */
39 vxworks_asm_out_constructor (rtx symbol
, int priority
)
43 sec
= get_cdtor_priority_section (priority
,
44 /*constructor_p=*/true);
45 assemble_addr_to_section (symbol
, sec
);
48 /* See comment for vxworks_asm_out_constructor. */
51 vxworks_asm_out_destructor (rtx symbol
, int priority
)
55 sec
= get_cdtor_priority_section (priority
,
56 /*constructor_p=*/false);
57 assemble_addr_to_section (symbol
, sec
);
60 /* Return the list of FIELD_DECLs that make up an emulated TLS
61 variable's control object. TYPE is the structure these are fields
62 of and *NAME will be filled in with the structure tag that should
66 vxworks_emutls_var_fields (tree type
, tree
*name
)
68 tree field
, next_field
;
70 *name
= get_identifier ("__tls_var");
72 field
= build_decl (FIELD_DECL
, get_identifier ("size"),
74 DECL_CONTEXT (field
) = type
;
77 field
= build_decl (FIELD_DECL
, get_identifier ("module_id"),
79 DECL_CONTEXT (field
) = type
;
80 TREE_CHAIN (field
) = next_field
;
83 field
= build_decl (FIELD_DECL
, get_identifier ("offset"),
85 DECL_CONTEXT (field
) = type
;
86 TREE_CHAIN (field
) = next_field
;
91 /* Return the CONSTRUCTOR to initialize an emulated TLS control
92 object. VAR is the control object. DECL is the TLS object itself
93 and TMPL_ADDR is the address (an ADDR_EXPR) of the initializer for
97 vxworks_emutls_var_init (tree var
, tree decl
, tree tmpl_addr
)
99 VEC(constructor_elt
,gc
) *v
= VEC_alloc (constructor_elt
, gc
, 3);
100 constructor_elt
*elt
;
102 tree type
= TREE_TYPE (var
);
103 tree field
= TYPE_FIELDS (type
);
105 elt
= VEC_quick_push (constructor_elt
, v
, NULL
);
107 elt
->value
= fold_convert (TREE_TYPE (field
), tmpl_addr
);
109 elt
= VEC_quick_push (constructor_elt
, v
, NULL
);
110 field
= TREE_CHAIN (field
);
112 elt
->value
= build_int_cst (TREE_TYPE (field
), 0);
114 elt
= VEC_quick_push (constructor_elt
, v
, NULL
);
115 field
= TREE_CHAIN (field
);
117 elt
->value
= fold_convert (TREE_TYPE (field
), DECL_SIZE_UNIT (decl
));
119 return build_constructor (type
, v
);
122 /* Do VxWorks-specific parts of OVERRIDE_OPTIONS. */
125 vxworks_override_options (void)
127 /* We don't support __thread via target hooks. */
128 targetm
.have_tls
= false;
130 targetm
.emutls
.get_address
= "__builtin___tls_lookup";
131 targetm
.emutls
.register_common
= NULL
;
132 targetm
.emutls
.var_section
= ".tls_vars";
133 targetm
.emutls
.tmpl_section
= ".tls_data";
134 targetm
.emutls
.var_prefix
= "__tls__";
135 targetm
.emutls
.tmpl_prefix
= "";
136 targetm
.emutls
.var_fields
= vxworks_emutls_var_fields
;
137 targetm
.emutls
.var_init
= vxworks_emutls_var_init
;
138 targetm
.emutls
.var_align_fixed
= true;
139 targetm
.emutls
.debug_form_tls_address
= true;
141 /* We can use .ctors/.dtors sections only in RTP mode. */
142 targetm
.have_ctors_dtors
= TARGET_VXWORKS_RTP
;
144 /* PIC is only supported for RTPs. */
145 if (flag_pic
&& !TARGET_VXWORKS_RTP
)
146 error ("PIC is only supported for RTPs");