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 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"
38 /* i386/PE specific attribute support.
40 i386/PE has two new attributes:
41 dllexport - for exporting a function/variable that will live in a dll
42 dllimport - for importing a function/variable from a dll
44 Microsoft allows multiple declspecs in one __declspec, separating
45 them with spaces. We do NOT support this. Instead, use __declspec
49 /* Handle a "shared" attribute;
50 arguments as in struct attribute_spec.handler. */
52 ix86_handle_shared_attribute (tree *node, tree name,
53 tree args ATTRIBUTE_UNUSED,
54 int flags ATTRIBUTE_UNUSED, bool *no_add_attrs)
56 if (TREE_CODE (*node) != VAR_DECL)
58 warning (OPT_Wattributes, "%qs attribute only applies to variables",
59 IDENTIFIER_POINTER (name));
66 /* Handle a "selectany" attribute;
67 arguments as in struct attribute_spec.handler. */
69 ix86_handle_selectany_attribute (tree *node, tree name,
70 tree args ATTRIBUTE_UNUSED,
71 int flags ATTRIBUTE_UNUSED,
74 /* The attribute applies only to objects that are initialized and have
75 external linkage. However, we may not know about initialization
76 until the language frontend has processed the decl. We'll check for
77 initialization later in encode_section_info. */
78 if (TREE_CODE (*node) != VAR_DECL || !TREE_PUBLIC (*node))
80 error ("%qs attribute applies only to initialized variables"
81 " with external linkage", IDENTIFIER_POINTER (name));
89 /* Return the type that we should use to determine if DECL is
90 imported or exported. */
93 associated_type (tree decl)
95 return (DECL_CONTEXT (decl) && TYPE_P (DECL_CONTEXT (decl))
96 ? DECL_CONTEXT (decl) : NULL_TREE);
99 /* Return true if DECL should be a dllexport'd object. */
102 i386_pe_determine_dllexport_p (tree decl)
106 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL)
109 if (lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl)))
112 /* Also mark class members of exported classes with dllexport. */
113 assoc = associated_type (decl);
114 if (assoc && lookup_attribute ("dllexport", TYPE_ATTRIBUTES (assoc)))
115 return i386_pe_type_dllexport_p (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 /* Lookup the attribute in addition to checking the DECL_DLLIMPORT_P flag.
131 We may need to override an earlier decision. */
132 if (DECL_DLLIMPORT_P (decl))
135 /* The DECL_DLLIMPORT_P flag was set for decls in the class definition
136 by targetm.cxx.adjust_class_at_definition. Check again to emit
137 warnings if the class attribute has been overridden by an
138 out-of-class definition. */
139 assoc = associated_type (decl);
140 if (assoc && lookup_attribute ("dllimport", TYPE_ATTRIBUTES (assoc)))
141 return i386_pe_type_dllimport_p (decl);
146 /* Handle the -mno-fun-dllimport target switch. */
149 i386_pe_valid_dllimport_attribute_p (const_tree decl)
151 if (TARGET_NOP_FUN_DLLIMPORT && TREE_CODE (decl) == FUNCTION_DECL)
156 /* Return string which is the function name, identified by ID, modified
157 with a suffix consisting of an atsign (@) followed by the number of
158 bytes of arguments. If ID is NULL use the DECL_NAME as base. If
159 FASTCALL is true, also add the FASTCALL_PREFIX.
160 Return NULL if no change required. */
163 gen_stdcall_or_fastcall_suffix (tree decl, tree id, bool fastcall)
165 HOST_WIDE_INT total = 0;
166 const char *old_str = IDENTIFIER_POINTER (id != NULL_TREE ? id : DECL_NAME (decl));
168 tree type = TREE_TYPE (decl);
170 function_args_iterator args_iter;
172 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL);
174 if (prototype_p (type))
176 /* This attribute is ignored for variadic functions. */
180 /* Quit if we hit an incomplete type. Error is reported
181 by convert_arguments in c-typeck.c or cp/typeck.c. */
182 FOREACH_FUNCTION_ARGS(type, arg, args_iter)
184 HOST_WIDE_INT parm_size;
185 HOST_WIDE_INT parm_boundary_bytes = PARM_BOUNDARY / BITS_PER_UNIT;
187 if (! COMPLETE_TYPE_P (arg))
190 parm_size = int_size_in_bytes (arg);
194 /* Must round up to include padding. This is done the same
195 way as in store_one_arg. */
196 parm_size = ((parm_size + parm_boundary_bytes - 1)
197 / parm_boundary_bytes * parm_boundary_bytes);
201 /* Assume max of 8 base 10 digits in the suffix. */
202 p = new_str = alloca (1 + strlen (old_str) + 1 + 8 + 1);
204 *p++ = FASTCALL_PREFIX;
205 sprintf (p, "%s@" HOST_WIDE_INT_PRINT_DEC, old_str, total);
207 return get_identifier (new_str);
210 /* Maybe decorate and get a new identifier for the DECL of a stdcall or
211 fastcall function. The original identifier is supplied in ID. */
214 i386_pe_maybe_mangle_decl_assembler_name (tree decl, tree id)
216 tree new_id = NULL_TREE;
218 if (TREE_CODE (decl) == FUNCTION_DECL)
220 tree type_attributes = TYPE_ATTRIBUTES (TREE_TYPE (decl));
221 if (lookup_attribute ("stdcall", type_attributes))
222 new_id = gen_stdcall_or_fastcall_suffix (decl, id, false);
223 else if (lookup_attribute ("fastcall", type_attributes))
224 new_id = gen_stdcall_or_fastcall_suffix (decl, id, true);
230 /* This is used as a target hook to modify the DECL_ASSEMBLER_NAME
231 in the language-independent default hook
232 langhooks,c:lhd_set_decl_assembler_name ()
233 and in cp/mangle,c:mangle_decl (). */
235 i386_pe_mangle_decl_assembler_name (tree decl, tree id)
237 tree new_id = i386_pe_maybe_mangle_decl_assembler_name (decl, id);
239 return (new_id ? new_id : id);
243 i386_pe_encode_section_info (tree decl, rtx rtl, int first)
248 /* Do this last, due to our frobbing of DECL_DLLIMPORT_P above. */
249 default_encode_section_info (decl, rtl, first);
251 /* Careful not to prod global register variables. */
255 symbol = XEXP (rtl, 0);
256 gcc_assert (GET_CODE (symbol) == SYMBOL_REF);
258 switch (TREE_CODE (decl))
263 /* FIXME: In Ada, and perhaps other language frontends,
264 imported stdcall names may not yet have been modified.
265 Check and do it know. */
267 tree old_id = DECL_ASSEMBLER_NAME (decl);
268 const char* asm_str = IDENTIFIER_POINTER (old_id);
269 /* Do not change the identifier if a verbatim asmspec
270 or if stdcall suffix already added. */
271 if (*asm_str == '*' || strchr (asm_str, '@'))
273 if ((new_id = i386_pe_maybe_mangle_decl_assembler_name (decl, old_id)))
275 /* These attributes must be present on first declaration,
276 change_decl_assembler_name will warn if they are added
277 later and the decl has been referenced, but duplicate_decls
278 should catch the mismatch first. */
279 change_decl_assembler_name (decl, new_id);
280 XSTR (symbol, 0) = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
286 if (lookup_attribute ("selectany", DECL_ATTRIBUTES (decl)))
288 if (DECL_INITIAL (decl)
289 /* If an object is initialized with a ctor, the static
290 initialization and destruction code for it is present in
291 each unit defining the object. The code that calls the
292 ctor is protected by a link-once guard variable, so that
293 the object still has link-once semantics, */
294 || TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (decl)))
295 make_decl_one_only (decl);
297 error ("%q+D:'selectany' attribute applies only to "
298 "initialized objects", decl);
306 /* Mark the decl so we can tell from the rtl whether the object is
307 dllexport'd or dllimport'd. tree.c: merge_dllimport_decl_attributes
308 handles dllexport/dllimport override semantics. */
309 flags = (SYMBOL_REF_FLAGS (symbol) &
310 ~(SYMBOL_FLAG_DLLIMPORT | SYMBOL_FLAG_DLLEXPORT));
311 if (i386_pe_determine_dllexport_p (decl))
312 flags |= SYMBOL_FLAG_DLLEXPORT;
313 else if (i386_pe_determine_dllimport_p (decl))
315 flags |= SYMBOL_FLAG_DLLIMPORT;
316 /* If we went through the associated_type path, this won't already
317 be set. Though, frankly, this seems wrong, and should be fixed
319 if (!DECL_DLLIMPORT_P (decl))
321 DECL_DLLIMPORT_P (decl) = 1;
322 flags &= ~SYMBOL_FLAG_LOCAL;
325 SYMBOL_REF_FLAGS (symbol) = flags;
329 i386_pe_binds_local_p (const_tree exp)
331 /* PE does not do dynamic binding. Indeed, the only kind of
332 non-local reference comes from a dllimport'd symbol. */
333 if ((TREE_CODE (exp) == VAR_DECL || TREE_CODE (exp) == FUNCTION_DECL)
334 && DECL_DLLIMPORT_P (exp))
340 /* Also strip the fastcall prefix and stdcall suffix. */
343 i386_pe_strip_name_encoding_full (const char *str)
346 const char *name = default_strip_name_encoding (str);
348 /* Strip leading '@' on fastcall symbols. */
352 /* Strip trailing "@n". */
353 p = strchr (name, '@');
355 return ggc_alloc_string (name, p - name);
361 i386_pe_unique_section (tree decl, int reloc)
364 const char *name, *prefix;
367 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
368 name = i386_pe_strip_name_encoding_full (name);
370 /* The object is put in, for example, section .text$foo.
371 The linker will then ultimately place them in .text
372 (everything from the $ on is stripped). Don't put
373 read-only data in .rdata section to avoid a PE linker
374 bug when .rdata$* grouped sections are used in code
375 without a .rdata section. */
376 if (TREE_CODE (decl) == FUNCTION_DECL)
378 else if (decl_readonly_section (decl, reloc))
382 len = strlen (name) + strlen (prefix);
383 string = alloca (len + 1);
384 sprintf (string, "%s%s", prefix, name);
386 DECL_SECTION_NAME (decl) = build_string (len, string);
389 /* Select a set of attributes for section NAME based on the properties
390 of DECL and whether or not RELOC indicates that DECL's initializer
391 might contain runtime relocations.
393 We make the section read-only and executable for a function decl,
394 read-only for a const data decl, and writable for a non-const data decl.
396 If the section has already been defined, to not allow it to have
397 different attributes, as (1) this is ambiguous since we're not seeing
398 all the declarations up front and (2) some assemblers (e.g. SVR4)
399 do not recognize section redefinitions. */
400 /* ??? This differs from the "standard" PE implementation in that we
401 handle the SHARED variable attribute. Should this be done for all
404 #define SECTION_PE_SHARED SECTION_MACH_DEP
407 i386_pe_section_type_flags (tree decl, const char *name, int reloc)
413 /* The names we put in the hashtable will always be the unique
414 versions given to us by the stringtable, so we can just use
415 their addresses as the keys. */
417 htab = htab_create (31, htab_hash_pointer, htab_eq_pointer, NULL);
419 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
420 flags = SECTION_CODE;
421 else if (decl && decl_readonly_section (decl, reloc))
425 flags = SECTION_WRITE;
427 if (decl && TREE_CODE (decl) == VAR_DECL
428 && lookup_attribute ("shared", DECL_ATTRIBUTES (decl)))
429 flags |= SECTION_PE_SHARED;
432 if (decl && DECL_ONE_ONLY (decl))
433 flags |= SECTION_LINKONCE;
435 /* See if we already have an entry for this section. */
436 slot = (unsigned int **) htab_find_slot (htab, name, INSERT);
439 *slot = (unsigned int *) xmalloc (sizeof (unsigned int));
444 if (decl && **slot != flags)
445 error ("%q+D causes a section type conflict", decl);
452 i386_pe_asm_named_section (const char *name, unsigned int flags,
455 char flagchars[8], *f = flagchars;
457 if ((flags & (SECTION_CODE | SECTION_WRITE)) == 0)
460 *f++ ='d'; /* This is necessary for older versions of gas. */
465 if (flags & SECTION_CODE)
467 if (flags & SECTION_WRITE)
469 if (flags & SECTION_PE_SHARED)
475 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
477 if (flags & SECTION_LINKONCE)
479 /* Functions may have been compiled at various levels of
480 optimization so we can't use `same_size' here.
481 Instead, have the linker pick one, without warning.
482 If 'selectany' attribute has been specified, MS compiler
483 sets 'discard' characteristic, rather than telling linker
484 to warn of size or content mismatch, so do the same. */
485 bool discard = (flags & SECTION_CODE)
486 || lookup_attribute ("selectany",
487 DECL_ATTRIBUTES (decl));
488 fprintf (asm_out_file, "\t.linkonce %s\n",
489 (discard ? "discard" : "same_size"));
494 i386_pe_asm_output_aligned_decl_common (FILE *stream, tree decl,
495 const char *name, HOST_WIDE_INT size,
496 HOST_WIDE_INT align ATTRIBUTE_UNUSED)
498 HOST_WIDE_INT rounded;
500 /* Compute as in assemble_noswitch_variable, since we don't actually
501 support aligned common. */
502 rounded = size ? size : 1;
503 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
504 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
505 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
507 i386_pe_maybe_record_exported_symbol (decl, name, 1);
509 fprintf (stream, "\t.comm\t");
510 assemble_name (stream, name);
511 fprintf (stream, ", " HOST_WIDE_INT_PRINT_DEC "\t" ASM_COMMENT_START
512 " " HOST_WIDE_INT_PRINT_DEC "\n",
516 /* The Microsoft linker requires that every function be marked as
517 DT_FCN. When using gas on cygwin, we must emit appropriate .type
522 /* Mark a function appropriately. This should only be called for
523 functions for which we are not emitting COFF debugging information.
524 FILE is the assembler output file, NAME is the name of the
525 function, and PUBLIC is nonzero if the function is globally
529 i386_pe_declare_function_type (FILE *file, const char *name, int public)
531 fprintf (file, "\t.def\t");
532 assemble_name (file, name);
533 fprintf (file, ";\t.scl\t%d;\t.type\t%d;\t.endef\n",
534 public ? (int) C_EXT : (int) C_STAT,
535 (int) DT_FCN << N_BTSHFT);
538 /* Keep a list of external functions. */
540 struct extern_list GTY(())
542 struct extern_list *next;
547 static GTY(()) struct extern_list *extern_head;
549 /* Assemble an external function reference. We need to keep a list of
550 these, so that we can output the function types at the end of the
551 assembly. We can't output the types now, because we might see a
552 definition of the function later on and emit debugging information
556 i386_pe_record_external_function (tree decl, const char *name)
558 struct extern_list *p;
560 p = (struct extern_list *) ggc_alloc (sizeof *p);
561 p->next = extern_head;
567 /* Keep a list of exported symbols. */
569 struct export_list GTY(())
571 struct export_list *next;
573 int is_data; /* used to type tag exported symbols. */
576 static GTY(()) struct export_list *export_head;
578 /* Assemble an export symbol entry. We need to keep a list of
579 these, so that we can output the export list at the end of the
580 assembly. We used to output these export symbols in each function,
581 but that causes problems with GNU ld when the sections are
585 i386_pe_maybe_record_exported_symbol (tree decl, const char *name, int is_data)
588 struct export_list *p;
590 symbol = XEXP (DECL_RTL (decl), 0);
591 gcc_assert (GET_CODE (symbol) == SYMBOL_REF);
592 if (!SYMBOL_REF_DLLEXPORT_P (symbol))
595 p = (struct export_list *) ggc_alloc (sizeof *p);
596 p->next = export_head;
598 p->is_data = is_data;
602 /* This is called at the end of assembly. For each external function
603 which has not been defined, we output a declaration now. We also
604 output the .drectve section. */
607 i386_pe_file_end (void)
609 struct extern_list *p;
613 for (p = extern_head; p != NULL; p = p->next)
619 /* Positively ensure only one declaration for any given symbol. */
620 if (! TREE_ASM_WRITTEN (decl)
621 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
623 TREE_ASM_WRITTEN (decl) = 1;
624 i386_pe_declare_function_type (asm_out_file, p->name,
631 struct export_list *q;
633 for (q = export_head; q != NULL; q = q->next)
635 fprintf (asm_out_file, "\t.ascii \" -export:%s%s\"\n",
636 default_strip_name_encoding (q->name),
637 (q->is_data ? ",data" : ""));
642 #include "gt-winnt.h"