1 /* Subroutines for insn-output.c for Windows NT.
2 Contributed by Douglas Rupp (drupp@cs.washington.edu)
3 Copyright (C) 1995, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
4 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, 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"
28 #include "hard-reg-set.h"
33 #include "diagnostic-core.h"
36 #include "langhooks.h"
39 #include "lto-streamer.h"
41 /* i386/PE specific attribute support.
43 i386/PE has two new attributes:
44 dllexport - for exporting a function/variable that will live in a dll
45 dllimport - for importing a function/variable from a dll
47 Microsoft allows multiple declspecs in one __declspec, separating
48 them with spaces. We do NOT support this. Instead, use __declspec
52 /* Handle a "shared" attribute;
53 arguments as in struct attribute_spec.handler. */
55 ix86_handle_shared_attribute (tree
*node
, tree name
,
56 tree args ATTRIBUTE_UNUSED
,
57 int flags ATTRIBUTE_UNUSED
, bool *no_add_attrs
)
59 if (TREE_CODE (*node
) != VAR_DECL
)
61 warning (OPT_Wattributes
, "%qE attribute only applies to variables",
69 /* Handle a "selectany" attribute;
70 arguments as in struct attribute_spec.handler. */
72 ix86_handle_selectany_attribute (tree
*node
, tree name
,
73 tree args ATTRIBUTE_UNUSED
,
74 int flags ATTRIBUTE_UNUSED
,
77 /* The attribute applies only to objects that are initialized and have
78 external linkage. However, we may not know about initialization
79 until the language frontend has processed the decl. We'll check for
80 initialization later in encode_section_info. */
81 if (TREE_CODE (*node
) != VAR_DECL
|| !TREE_PUBLIC (*node
))
83 error ("%qE attribute applies only to initialized variables"
84 " with external linkage", name
);
92 /* Return the type that we should use to determine if DECL is
93 imported or exported. */
96 associated_type (tree decl
)
98 return (DECL_CONTEXT (decl
) && TYPE_P (DECL_CONTEXT (decl
))
99 ? DECL_CONTEXT (decl
) : NULL_TREE
);
102 /* Return true if DECL should be a dllexport'd object. */
105 i386_pe_determine_dllexport_p (tree decl
)
107 if (TREE_CODE (decl
) != VAR_DECL
&& TREE_CODE (decl
) != FUNCTION_DECL
)
110 /* Don't export local clones of dllexports. */
111 if (!TREE_PUBLIC (decl
))
114 if (lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl
)))
120 /* Return true if DECL should be a dllimport'd object. */
123 i386_pe_determine_dllimport_p (tree decl
)
127 if (TREE_CODE (decl
) != VAR_DECL
&& TREE_CODE (decl
) != FUNCTION_DECL
)
130 if (DECL_DLLIMPORT_P (decl
))
133 /* The DECL_DLLIMPORT_P flag was set for decls in the class definition
134 by targetm.cxx.adjust_class_at_definition. Check again to emit
135 error message if the class attribute has been overridden by an
136 out-of-class definition of static data. */
137 assoc
= associated_type (decl
);
138 if (assoc
&& lookup_attribute ("dllimport", TYPE_ATTRIBUTES (assoc
))
139 && TREE_CODE (decl
) == VAR_DECL
140 && TREE_STATIC (decl
) && TREE_PUBLIC (decl
)
141 && !DECL_EXTERNAL (decl
)
142 /* vtable's are linkonce constants, so defining a vtable is not
143 an error as long as we don't try to import it too. */
144 && !DECL_VIRTUAL_P (decl
))
145 error ("definition of static data member %q+D of "
146 "dllimport'd class", decl
);
151 /* Handle the -mno-fun-dllimport target switch. */
154 i386_pe_valid_dllimport_attribute_p (const_tree decl
)
156 if (TARGET_NOP_FUN_DLLIMPORT
&& TREE_CODE (decl
) == FUNCTION_DECL
)
161 /* Return string which is the function name, identified by ID, modified
162 with a suffix consisting of an atsign (@) followed by the number of
163 bytes of arguments. If ID is NULL use the DECL_NAME as base. If
164 FASTCALL is true, also add the FASTCALL_PREFIX.
165 Return NULL if no change required. */
168 gen_stdcall_or_fastcall_suffix (tree decl
, tree id
, bool fastcall
)
170 HOST_WIDE_INT total
= 0;
171 const char *old_str
= IDENTIFIER_POINTER (id
!= NULL_TREE
? id
: DECL_NAME (decl
));
173 tree type
= TREE_TYPE (decl
);
175 function_args_iterator args_iter
;
177 gcc_assert (TREE_CODE (decl
) == FUNCTION_DECL
);
179 if (prototype_p (type
))
181 /* This attribute is ignored for variadic functions. */
185 /* Quit if we hit an incomplete type. Error is reported
186 by convert_arguments in c-typeck.c or cp/typeck.c. */
187 FOREACH_FUNCTION_ARGS(type
, arg
, args_iter
)
189 HOST_WIDE_INT parm_size
;
190 HOST_WIDE_INT parm_boundary_bytes
= PARM_BOUNDARY
/ BITS_PER_UNIT
;
192 if (! COMPLETE_TYPE_P (arg
))
195 parm_size
= int_size_in_bytes (arg
);
199 /* Must round up to include padding. This is done the same
200 way as in store_one_arg. */
201 parm_size
= ((parm_size
+ parm_boundary_bytes
- 1)
202 / parm_boundary_bytes
* parm_boundary_bytes
);
206 /* Assume max of 8 base 10 digits in the suffix. */
207 p
= new_str
= XALLOCAVEC (char, 1 + strlen (old_str
) + 1 + 8 + 1);
209 *p
++ = FASTCALL_PREFIX
;
210 sprintf (p
, "%s@" HOST_WIDE_INT_PRINT_DEC
, old_str
, total
);
212 return get_identifier (new_str
);
215 /* Maybe decorate and get a new identifier for the DECL of a stdcall or
216 fastcall function. The original identifier is supplied in ID. */
219 i386_pe_maybe_mangle_decl_assembler_name (tree decl
, tree id
)
221 tree new_id
= NULL_TREE
;
223 if (TREE_CODE (decl
) == FUNCTION_DECL
)
225 tree type_attributes
= TYPE_ATTRIBUTES (TREE_TYPE (decl
));
226 if (lookup_attribute ("stdcall", type_attributes
))
227 new_id
= gen_stdcall_or_fastcall_suffix (decl
, id
, false);
228 else if (lookup_attribute ("fastcall", type_attributes
))
229 new_id
= gen_stdcall_or_fastcall_suffix (decl
, id
, true);
235 /* This is used as a target hook to modify the DECL_ASSEMBLER_NAME
236 in the language-independent default hook
237 langhooks,c:lhd_set_decl_assembler_name ()
238 and in cp/mangle,c:mangle_decl (). */
240 i386_pe_mangle_decl_assembler_name (tree decl
, tree id
)
242 tree new_id
= i386_pe_maybe_mangle_decl_assembler_name (decl
, id
);
244 return (new_id
? new_id
: id
);
248 i386_pe_encode_section_info (tree decl
, rtx rtl
, int first
)
253 /* Do this last, due to our frobbing of DECL_DLLIMPORT_P above. */
254 default_encode_section_info (decl
, rtl
, first
);
256 /* Careful not to prod global register variables. */
260 symbol
= XEXP (rtl
, 0);
261 gcc_assert (GET_CODE (symbol
) == SYMBOL_REF
);
263 switch (TREE_CODE (decl
))
266 /* FIXME: Imported stdcall names are not modified by the Ada frontend.
267 Check and decorate the RTL name now. */
268 if (strcmp (lang_hooks
.name
, "GNU Ada") == 0)
271 tree old_id
= DECL_ASSEMBLER_NAME (decl
);
272 const char* asm_str
= IDENTIFIER_POINTER (old_id
);
273 /* Do not change the identifier if a verbatim asmspec
274 or if stdcall suffix already added. */
275 if (!(*asm_str
== '*' || strchr (asm_str
, '@'))
276 && (new_id
= i386_pe_maybe_mangle_decl_assembler_name (decl
,
278 XSTR (symbol
, 0) = IDENTIFIER_POINTER (new_id
);
283 if (lookup_attribute ("selectany", DECL_ATTRIBUTES (decl
)))
285 if (DECL_INITIAL (decl
)
286 /* If an object is initialized with a ctor, the static
287 initialization and destruction code for it is present in
288 each unit defining the object. The code that calls the
289 ctor is protected by a link-once guard variable, so that
290 the object still has link-once semantics, */
291 || TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (decl
)))
292 make_decl_one_only (decl
, DECL_ASSEMBLER_NAME (decl
));
294 error ("%q+D:'selectany' attribute applies only to "
295 "initialized objects", decl
);
303 /* Mark the decl so we can tell from the rtl whether the object is
304 dllexport'd or dllimport'd. tree.c: merge_dllimport_decl_attributes
305 handles dllexport/dllimport override semantics. */
306 flags
= (SYMBOL_REF_FLAGS (symbol
) &
307 ~(SYMBOL_FLAG_DLLIMPORT
| SYMBOL_FLAG_DLLEXPORT
));
308 if (i386_pe_determine_dllexport_p (decl
))
309 flags
|= SYMBOL_FLAG_DLLEXPORT
;
310 else if (i386_pe_determine_dllimport_p (decl
))
311 flags
|= SYMBOL_FLAG_DLLIMPORT
;
313 SYMBOL_REF_FLAGS (symbol
) = flags
;
317 i386_pe_binds_local_p (const_tree exp
)
319 /* PE does not do dynamic binding. Indeed, the only kind of
320 non-local reference comes from a dllimport'd symbol. */
321 if ((TREE_CODE (exp
) == VAR_DECL
|| TREE_CODE (exp
) == FUNCTION_DECL
)
322 && DECL_DLLIMPORT_P (exp
))
325 /* Or a weak one, now that they are supported. */
326 if ((TREE_CODE (exp
) == VAR_DECL
|| TREE_CODE (exp
) == FUNCTION_DECL
)
328 /* But x64 gets confused and attempts to use unsupported GOTPCREL
329 relocations if we tell it the truth, so we still return true in
330 that case until the deeper problem can be fixed. */
331 return (TARGET_64BIT
&& DEFAULT_ABI
== MS_ABI
);
336 /* Also strip the fastcall prefix and stdcall suffix. */
339 i386_pe_strip_name_encoding_full (const char *str
)
342 const char *name
= default_strip_name_encoding (str
);
344 /* Strip leading '@' on fastcall symbols. */
348 /* Strip trailing "@n". */
349 p
= strchr (name
, '@');
351 return ggc_alloc_string (name
, p
- name
);
357 i386_pe_unique_section (tree decl
, int reloc
)
360 const char *name
, *prefix
;
363 name
= IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl
));
364 name
= i386_pe_strip_name_encoding_full (name
);
366 /* The object is put in, for example, section .text$foo.
367 The linker will then ultimately place them in .text
368 (everything from the $ on is stripped). Don't put
369 read-only data in .rdata section to avoid a PE linker
370 bug when .rdata$* grouped sections are used in code
371 without a .rdata section. */
372 if (TREE_CODE (decl
) == FUNCTION_DECL
)
374 else if (decl_readonly_section (decl
, reloc
))
378 len
= strlen (name
) + strlen (prefix
);
379 string
= XALLOCAVEC (char, len
+ 1);
380 sprintf (string
, "%s%s", prefix
, name
);
382 DECL_SECTION_NAME (decl
) = build_string (len
, string
);
385 /* Select a set of attributes for section NAME based on the properties
386 of DECL and whether or not RELOC indicates that DECL's initializer
387 might contain runtime relocations.
389 We make the section read-only and executable for a function decl,
390 read-only for a const data decl, and writable for a non-const data decl.
392 If the section has already been defined, to not allow it to have
393 different attributes, as (1) this is ambiguous since we're not seeing
394 all the declarations up front and (2) some assemblers (e.g. SVR4)
395 do not recognize section redefinitions. */
396 /* ??? This differs from the "standard" PE implementation in that we
397 handle the SHARED variable attribute. Should this be done for all
400 #define SECTION_PE_SHARED SECTION_MACH_DEP
403 i386_pe_section_type_flags (tree decl
, const char *name
, int reloc
)
409 /* The names we put in the hashtable will always be the unique
410 versions given to us by the stringtable, so we can just use
411 their addresses as the keys. */
413 htab
= htab_create (31, htab_hash_pointer
, htab_eq_pointer
, NULL
);
415 if (decl
&& TREE_CODE (decl
) == FUNCTION_DECL
)
416 flags
= SECTION_CODE
;
417 else if (decl
&& decl_readonly_section (decl
, reloc
))
419 else if (current_function_decl
421 && crtl
->subsections
.unlikely_text_section_name
422 && strcmp (name
, crtl
->subsections
.unlikely_text_section_name
) == 0)
423 flags
= SECTION_CODE
;
425 && (!current_function_decl
|| !cfun
)
426 && strcmp (name
, UNLIKELY_EXECUTED_TEXT_SECTION_NAME
) == 0)
427 flags
= SECTION_CODE
;
430 flags
= SECTION_WRITE
;
432 if (decl
&& TREE_CODE (decl
) == VAR_DECL
433 && lookup_attribute ("shared", DECL_ATTRIBUTES (decl
)))
434 flags
|= SECTION_PE_SHARED
;
437 if (decl
&& DECL_ONE_ONLY (decl
))
438 flags
|= SECTION_LINKONCE
;
440 /* See if we already have an entry for this section. */
441 slot
= (unsigned int **) htab_find_slot (htab
, name
, INSERT
);
444 *slot
= (unsigned int *) xmalloc (sizeof (unsigned int));
449 if (decl
&& **slot
!= flags
)
450 error ("%q+D causes a section type conflict", decl
);
457 i386_pe_asm_named_section (const char *name
, unsigned int flags
,
460 char flagchars
[8], *f
= flagchars
;
462 if ((flags
& (SECTION_CODE
| SECTION_WRITE
)) == 0)
465 *f
++ ='d'; /* This is necessary for older versions of gas. */
470 if (flags
& SECTION_CODE
)
472 if (flags
& SECTION_WRITE
)
474 if (flags
& SECTION_PE_SHARED
)
478 /* LTO sections need 1-byte alignment to avoid confusing the
479 zlib decompression algorithm with trailing zero pad bytes. */
480 if (strncmp (name
, LTO_SECTION_NAME_PREFIX
,
481 strlen (LTO_SECTION_NAME_PREFIX
)) == 0)
486 fprintf (asm_out_file
, "\t.section\t%s,\"%s\"\n", name
, flagchars
);
488 if (flags
& SECTION_LINKONCE
)
490 /* Functions may have been compiled at various levels of
491 optimization so we can't use `same_size' here.
492 Instead, have the linker pick one, without warning.
493 If 'selectany' attribute has been specified, MS compiler
494 sets 'discard' characteristic, rather than telling linker
495 to warn of size or content mismatch, so do the same. */
496 bool discard
= (flags
& SECTION_CODE
)
497 || lookup_attribute ("selectany",
498 DECL_ATTRIBUTES (decl
));
499 fprintf (asm_out_file
, "\t.linkonce %s\n",
500 (discard
? "discard" : "same_size"));
504 /* Beware, DECL may be NULL if compile_file() is emitting the LTO marker. */
507 i386_pe_asm_output_aligned_decl_common (FILE *stream
, tree decl
,
508 const char *name
, HOST_WIDE_INT size
,
509 HOST_WIDE_INT align ATTRIBUTE_UNUSED
)
511 HOST_WIDE_INT rounded
;
513 /* Compute as in assemble_noswitch_variable, since we don't have
514 support for aligned common on older binutils. We must also
515 avoid emitting a common symbol of size zero, as this is the
516 overloaded representation that indicates an undefined external
517 symbol in the PE object file format. */
518 rounded
= size
? size
: 1;
519 rounded
+= (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
) - 1;
520 rounded
= (rounded
/ (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
)
521 * (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
));
523 i386_pe_maybe_record_exported_symbol (decl
, name
, 1);
525 fprintf (stream
, "\t.comm\t");
526 assemble_name (stream
, name
);
527 if (use_pe_aligned_common
)
528 fprintf (stream
, ", " HOST_WIDE_INT_PRINT_DEC
", %d\n",
529 size
? size
: (HOST_WIDE_INT
) 1,
530 exact_log2 (align
) - exact_log2 (CHAR_BIT
));
532 fprintf (stream
, ", " HOST_WIDE_INT_PRINT_DEC
"\t" ASM_COMMENT_START
533 " " HOST_WIDE_INT_PRINT_DEC
"\n", rounded
, size
);
536 /* The Microsoft linker requires that every function be marked as
537 DT_FCN. When using gas on cygwin, we must emit appropriate .type
542 /* Mark a function appropriately. This should only be called for
543 functions for which we are not emitting COFF debugging information.
544 FILE is the assembler output file, NAME is the name of the
545 function, and PUB is nonzero if the function is globally
549 i386_pe_declare_function_type (FILE *file
, const char *name
, int pub
)
551 fprintf (file
, "\t.def\t");
552 assemble_name (file
, name
);
553 fprintf (file
, ";\t.scl\t%d;\t.type\t%d;\t.endef\n",
554 pub
? (int) C_EXT
: (int) C_STAT
,
555 (int) DT_FCN
<< N_BTSHFT
);
558 /* Keep a list of external functions. */
560 struct GTY(()) extern_list
562 struct extern_list
*next
;
567 static GTY(()) struct extern_list
*extern_head
;
569 /* Assemble an external function reference. We need to keep a list of
570 these, so that we can output the function types at the end of the
571 assembly. We can't output the types now, because we might see a
572 definition of the function later on and emit debugging information
576 i386_pe_record_external_function (tree decl
, const char *name
)
578 struct extern_list
*p
;
580 p
= ggc_alloc_extern_list ();
581 p
->next
= extern_head
;
587 /* Keep a list of exported symbols. */
589 struct GTY(()) export_list
591 struct export_list
*next
;
593 int is_data
; /* used to type tag exported symbols. */
596 static GTY(()) struct export_list
*export_head
;
598 /* Assemble an export symbol entry. We need to keep a list of
599 these, so that we can output the export list at the end of the
600 assembly. We used to output these export symbols in each function,
601 but that causes problems with GNU ld when the sections are
602 linkonce. Beware, DECL may be NULL if compile_file() is emitting
606 i386_pe_maybe_record_exported_symbol (tree decl
, const char *name
, int is_data
)
609 struct export_list
*p
;
614 symbol
= XEXP (DECL_RTL (decl
), 0);
615 gcc_assert (GET_CODE (symbol
) == SYMBOL_REF
);
616 if (!SYMBOL_REF_DLLEXPORT_P (symbol
))
619 gcc_assert (TREE_PUBLIC (decl
));
621 p
= ggc_alloc_export_list ();
622 p
->next
= export_head
;
624 p
->is_data
= is_data
;
628 #ifdef CXX_WRAP_SPEC_LIST
630 /* Hash table equality helper function. */
633 wrapper_strcmp (const void *x
, const void *y
)
635 return !strcmp ((const char *) x
, (const char *) y
);
638 /* Search for a function named TARGET in the list of library wrappers
639 we are using, returning a pointer to it if found or NULL if not.
640 This function might be called on quite a few symbols, and we only
641 have the list of names of wrapped functions available to us as a
642 spec string, so first time round we lazily initialise a hash table
643 to make things quicker. */
646 i386_find_on_wrapper_list (const char *target
)
648 static char first_time
= 1;
649 static htab_t wrappers
;
653 /* Beware that this is not a complicated parser, it assumes
654 that any sequence of non-whitespace beginning with an
655 underscore is one of the wrapped symbols. For now that's
656 adequate to distinguish symbols from spec substitutions
657 and command-line options. */
658 static char wrapper_list_buffer
[] = CXX_WRAP_SPEC_LIST
;
660 /* Breaks up the char array into separated strings
661 strings and enter them into the hash table. */
662 wrappers
= htab_create_alloc (8, htab_hash_string
, wrapper_strcmp
,
664 for (bufptr
= wrapper_list_buffer
; *bufptr
; ++bufptr
)
667 if (ISSPACE (*bufptr
))
671 while (*bufptr
&& !ISSPACE (*bufptr
))
676 *htab_find_slot (wrappers
, found
, INSERT
) = found
;
681 return (const char *) htab_find (wrappers
, target
);
684 #endif /* CXX_WRAP_SPEC_LIST */
686 /* This is called at the end of assembly. For each external function
687 which has not been defined, we output a declaration now. We also
688 output the .drectve section. */
691 i386_pe_file_end (void)
693 struct extern_list
*p
;
695 for (p
= extern_head
; p
!= NULL
; p
= p
->next
)
701 /* Positively ensure only one declaration for any given symbol. */
702 if (! TREE_ASM_WRITTEN (decl
)
703 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl
)))
705 #ifdef CXX_WRAP_SPEC_LIST
706 /* To ensure the DLL that provides the corresponding real
707 functions is still loaded at runtime, we must reference
708 the real function so that an (unused) import is created. */
709 const char *realsym
= i386_find_on_wrapper_list (p
->name
);
711 i386_pe_declare_function_type (asm_out_file
,
712 concat ("__real_", realsym
, NULL
), TREE_PUBLIC (decl
));
713 #endif /* CXX_WRAP_SPEC_LIST */
714 TREE_ASM_WRITTEN (decl
) = 1;
715 i386_pe_declare_function_type (asm_out_file
, p
->name
,
722 struct export_list
*q
;
724 for (q
= export_head
; q
!= NULL
; q
= q
->next
)
726 fprintf (asm_out_file
, "\t.ascii \" -export:\\\"%s\\\"%s\"\n",
727 default_strip_name_encoding (q
->name
),
728 (q
->is_data
? ",data" : ""));
733 #include "gt-winnt.h"