/* Handle #pragma, system V.4 style. Supports #pragma weak and #pragma pack.
- Copyright (C) 1992 Free Software Foundation, Inc.
+ Copyright (C) 1992, 1997, 1998, 1999, 2000, 2001, 2002
+ Free Software Foundation, Inc.
-This file is part of GNU CC.
+This file is part of GCC.
-GNU CC 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 2, or (at your option)
-any later version.
+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 2, or (at your option) any later
+version.
-GNU CC 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.
+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 GNU CC; see the file COPYING. If not, write to
-the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+along with GCC; see the file COPYING. If not, write to the Free
+Software Foundation, 59 Temple Place - Suite 330, Boston, MA
+02111-1307, USA. */
-#include <stdio.h>
#include "config.h"
+#include "system.h"
+#include "rtl.h"
#include "tree.h"
#include "function.h"
-#include "defaults.h"
+#include "cpplib.h"
#include "c-pragma.h"
+#include "flags.h"
+#include "toplev.h"
+#include "ggc.h"
+#include "c-common.h"
+#include "output.h"
+#include "tm_p.h"
-#ifdef HANDLE_SYSV_PRAGMA
+#define GCC_BAD(msgid) do { warning (msgid); return; } while (0)
+#define GCC_BAD2(msgid, arg) do { warning (msgid, arg); return; } while (0)
-/* When structure field packing is in effect, this variable is the
- number of bits to use as the maximum alignment. When packing is not
- in effect, this is zero. */
+#ifdef HANDLE_PRAGMA_PACK
+static void handle_pragma_pack PARAMS ((cpp_reader *));
-extern int maximum_field_alignment;
+#ifdef HANDLE_PRAGMA_PACK_PUSH_POP
+typedef struct align_stack
+{
+ int alignment;
+ unsigned int num_pushes;
+ tree id;
+ struct align_stack * prev;
+} align_stack;
-/* File used for outputting assembler code. */
-extern FILE *asm_out_file;
+static struct align_stack * alignment_stack = NULL;
-/* Handle one token of a pragma directive. TOKEN is the
- current token, and STRING is its printable form. */
+/* If we have a "global" #pragma pack(<n>) in effect when the first
+ #pragma pack(push,<n>) is encountered, this stores the value of
+ maximum_field_alignment in effect. When the final pop_alignment()
+ happens, we restore the value to this, not to a value of 0 for
+ maximum_field_alignment. Value is in bits. */
+static int default_alignment;
+#define SET_GLOBAL_ALIGNMENT(ALIGN) \
+ (default_alignment = maximum_field_alignment = (ALIGN))
-void
-handle_pragma_token (string, token)
- char *string;
- tree token;
-{
- static enum pragma_state state = ps_start, type;
- static char *name;
- static char *value;
- static int align;
+static void push_alignment PARAMS ((int, tree));
+static void pop_alignment PARAMS ((tree));
+static void mark_align_stack PARAMS ((void *));
- if (string == 0)
+/* Push an alignment value onto the stack. */
+static void
+push_alignment (alignment, id)
+ int alignment;
+ tree id;
+{
+ if (alignment_stack == NULL
+ || alignment_stack->alignment != alignment
+ || id != NULL_TREE)
{
- if (type == ps_pack)
- {
- if (state == ps_right)
- maximum_field_alignment = align * 8;
- else
- warning ("malformed `#pragma pack'");
- }
- else if (type == ps_weak)
- {
-#ifdef HANDLE_PRAGMA_WEAK
- if (HANDLE_PRAGMA_WEAK)
- handle_pragma_weak (state, name, value);
+ align_stack * entry;
-#endif /* HANDLE_PRAMA_WEAK */
- }
+ entry = (align_stack *) xmalloc (sizeof (* entry));
- type = state = ps_start;
+ entry->alignment = alignment;
+ entry->num_pushes = 1;
+ entry->id = id;
+ entry->prev = alignment_stack;
+
+ /* The current value of maximum_field_alignment is not necessarily
+ 0 since there may be a #pragma pack(<n>) in effect; remember it
+ so that we can restore it after the final #pragma pop(). */
+ if (alignment_stack == NULL)
+ default_alignment = maximum_field_alignment;
+
+ alignment_stack = entry;
+
+ maximum_field_alignment = alignment;
+ }
+ else
+ alignment_stack->num_pushes ++;
+}
+
+/* Undo a push of an alignment onto the stack. */
+static void
+pop_alignment (id)
+ tree id;
+{
+ align_stack * entry;
+
+ if (alignment_stack == NULL)
+ {
+ warning ("\
+#pragma pack (pop) encountered without matching #pragma pack (push, <n>)"
+ );
return;
}
- switch (state)
+ /* If we got an identifier, strip away everything above the target
+ entry so that the next step will restore the state just below it. */
+ if (id)
{
- case ps_start:
- if (token && TREE_CODE (token) == IDENTIFIER_NODE)
- {
- if (strcmp (IDENTIFIER_POINTER (token), "pack") == 0)
- type = state = ps_pack;
- else if (strcmp (IDENTIFIER_POINTER (token), "weak") == 0)
- type = state = ps_weak;
- else
- type = state = ps_done;
- }
+ for (entry = alignment_stack; entry; entry = entry->prev)
+ if (entry->id == id)
+ {
+ entry->num_pushes = 1;
+ alignment_stack = entry;
+ break;
+ }
+ if (entry == NULL)
+ warning ("\
+#pragma pack(pop, %s) encountered without matching #pragma pack(push, %s, <n>)"
+ , IDENTIFIER_POINTER (id), IDENTIFIER_POINTER (id));
+ }
+
+ if (-- alignment_stack->num_pushes == 0)
+ {
+ entry = alignment_stack->prev;
+
+ if (entry == NULL)
+ maximum_field_alignment = default_alignment;
else
- type = state = ps_done;
- break;
+ maximum_field_alignment = entry->alignment;
- case ps_weak:
- if (token && TREE_CODE (token) == IDENTIFIER_NODE)
- {
- name = IDENTIFIER_POINTER (token);
- state = ps_name;
- }
+ free (alignment_stack);
+
+ alignment_stack = entry;
+ }
+}
+
+static void
+mark_align_stack (p)
+ void *p;
+{
+ align_stack *a = *(align_stack **) p;
+
+ while (a)
+ {
+ ggc_mark_tree (a->id);
+ a = a->prev;
+ }
+}
+#else /* not HANDLE_PRAGMA_PACK_PUSH_POP */
+#define SET_GLOBAL_ALIGNMENT(ALIGN) (maximum_field_alignment = (ALIGN))
+#define push_alignment(ID, N) \
+ GCC_BAD("#pragma pack(push[, id], <n>) is not supported on this target")
+#define pop_alignment(ID) \
+ GCC_BAD("#pragma pack(pop[, id], <n>) is not supported on this target")
+#endif /* HANDLE_PRAGMA_PACK_PUSH_POP */
+
+/* #pragma pack ()
+ #pragma pack (N)
+
+ #pragma pack (push, N)
+ #pragma pack (push, ID, N)
+ #pragma pack (pop)
+ #pragma pack (pop, ID) */
+static void
+handle_pragma_pack (dummy)
+ cpp_reader *dummy ATTRIBUTE_UNUSED;
+{
+ tree x, id = 0;
+ int align = -1;
+ enum cpp_ttype token;
+ enum { set, push, pop } action;
+
+ if (c_lex (&x) != CPP_OPEN_PAREN)
+ GCC_BAD ("missing '(' after '#pragma pack' - ignored");
+
+ token = c_lex (&x);
+ if (token == CPP_CLOSE_PAREN)
+ {
+ action = set;
+ align = 0;
+ }
+ else if (token == CPP_NUMBER)
+ {
+ align = TREE_INT_CST_LOW (x);
+ action = set;
+ if (c_lex (&x) != CPP_CLOSE_PAREN)
+ GCC_BAD ("malformed '#pragma pack' - ignored");
+ }
+ else if (token == CPP_NAME)
+ {
+#define GCC_BAD_ACTION do { if (action == push) \
+ GCC_BAD ("malformed '#pragma pack(push[, id], <n>)' - ignored"); \
+ else \
+ GCC_BAD ("malformed '#pragma pack(pop[, id])' - ignored"); \
+ } while (0)
+
+ const char *op = IDENTIFIER_POINTER (x);
+ if (!strcmp (op, "push"))
+ action = push;
+ else if (!strcmp (op, "pop"))
+ action = pop;
else
- state = ps_bad;
- break;
+ GCC_BAD2 ("unknown action '%s' for '#pragma pack' - ignored", op);
- case ps_name:
- state = (strcmp (string, "=") ? ps_bad : ps_equals);
- break;
+ token = c_lex (&x);
+ if (token != CPP_COMMA && action == push)
+ GCC_BAD_ACTION;
- case ps_equals:
- if (token && TREE_CODE (token) == IDENTIFIER_NODE)
+ if (token == CPP_COMMA)
{
- value = IDENTIFIER_POINTER (token);
- state = ps_value;
+ token = c_lex (&x);
+ if (token == CPP_NAME)
+ {
+ id = x;
+ if (action == push && c_lex (&x) != CPP_COMMA)
+ GCC_BAD_ACTION;
+ token = c_lex (&x);
+ }
+
+ if (action == push)
+ {
+ if (token == CPP_NUMBER)
+ {
+ align = TREE_INT_CST_LOW (x);
+ token = c_lex (&x);
+ }
+ else
+ GCC_BAD_ACTION;
+ }
}
- else
- state = ps_bad;
- break;
- case ps_value:
- state = ps_bad;
- break;
+ if (token != CPP_CLOSE_PAREN)
+ GCC_BAD_ACTION;
+#undef GCC_BAD_ACTION
+ }
+ else
+ GCC_BAD ("malformed '#pragma pack' - ignored");
- case ps_pack:
- if (strcmp (string, "(") == 0)
- state = ps_left;
- else
- state = ps_bad;
- break;
+ if (c_lex (&x) != CPP_EOF)
+ warning ("junk at end of '#pragma pack'");
- case ps_left:
- if (token && TREE_CODE (token) == INTEGER_CST
- && TREE_INT_CST_HIGH (token) == 0)
- switch (TREE_INT_CST_LOW (token))
- {
- case 1:
- case 2:
- case 4:
- align = TREE_INT_CST_LOW (token);
- state = ps_align;
- break;
+ if (action != pop)
+ switch (align)
+ {
+ case 0:
+ case 1:
+ case 2:
+ case 4:
+ case 8:
+ case 16:
+ align *= BITS_PER_UNIT;
+ break;
+ default:
+ GCC_BAD2 ("alignment must be a small power of two, not %d", align);
+ }
- default:
- state = ps_bad;
- }
- else if (! token && strcmp (string, ")") == 0)
+ switch (action)
+ {
+ case set: SET_GLOBAL_ALIGNMENT (align); break;
+ case push: push_alignment (align, id); break;
+ case pop: pop_alignment (id); break;
+ }
+}
+#endif /* HANDLE_PRAGMA_PACK */
+
+#ifdef HANDLE_PRAGMA_WEAK
+static void apply_pragma_weak PARAMS ((tree, tree));
+static void handle_pragma_weak PARAMS ((cpp_reader *));
+
+static tree pending_weaks;
+
+static void
+apply_pragma_weak (decl, value)
+ tree decl, value;
+{
+ if (value)
+ {
+ value = build_string (IDENTIFIER_LENGTH (value),
+ IDENTIFIER_POINTER (value));
+ decl_attributes (&decl, build_tree_list (get_identifier ("alias"),
+ build_tree_list (NULL, value)),
+ 0);
+ }
+
+ if (SUPPORTS_WEAK && DECL_EXTERNAL (decl) && TREE_USED (decl)
+ && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))
+ warning_with_decl (decl, "applying #pragma weak `%s' after first use results in unspecified behavior");
+
+ declare_weak (decl);
+}
+
+void
+maybe_apply_pragma_weak (decl)
+ tree decl;
+{
+ tree *p, t, id;
+
+ /* Copied from the check in set_decl_assembler_name. */
+ if (TREE_CODE (decl) == FUNCTION_DECL
+ || (TREE_CODE (decl) == VAR_DECL
+ && (TREE_STATIC (decl)
+ || DECL_EXTERNAL (decl)
+ || TREE_PUBLIC (decl))))
+ id = DECL_ASSEMBLER_NAME (decl);
+ else
+ return;
+
+ for (p = &pending_weaks; (t = *p) ; p = &TREE_CHAIN (t))
+ if (id == TREE_PURPOSE (t))
+ {
+ apply_pragma_weak (decl, TREE_VALUE (t));
+ *p = TREE_CHAIN (t);
+ break;
+ }
+}
+
+/* #pragma weak name [= value] */
+static void
+handle_pragma_weak (dummy)
+ cpp_reader *dummy ATTRIBUTE_UNUSED;
+{
+ tree name, value, x, decl;
+ enum cpp_ttype t;
+
+ value = 0;
+
+ if (c_lex (&name) != CPP_NAME)
+ GCC_BAD ("malformed #pragma weak, ignored");
+ t = c_lex (&x);
+ if (t == CPP_EQ)
+ {
+ if (c_lex (&value) != CPP_NAME)
+ GCC_BAD ("malformed #pragma weak, ignored");
+ t = c_lex (&x);
+ }
+ if (t != CPP_EOF)
+ warning ("junk at end of #pragma weak");
+
+ decl = identifier_global_value (name);
+ if (decl && TREE_CODE_CLASS (TREE_CODE (decl)) == 'd')
+ {
+ apply_pragma_weak (decl, value);
+ if (value)
+ assemble_alias (decl, value);
+ }
+ else
+ pending_weaks = tree_cons (name, value, pending_weaks);
+}
+#else
+void
+maybe_apply_pragma_weak (decl)
+ tree decl ATTRIBUTE_UNUSED;
+{
+}
+#endif /* HANDLE_PRAGMA_WEAK */
+
+#ifdef HANDLE_PRAGMA_REDEFINE_EXTNAME
+static void handle_pragma_redefine_extname PARAMS ((cpp_reader *));
+
+static tree pending_redefine_extname;
+
+/* #pragma redefined_extname oldname newname */
+static void
+handle_pragma_redefine_extname (dummy)
+ cpp_reader *dummy ATTRIBUTE_UNUSED;
+{
+ tree oldname, newname, decl, x;
+ enum cpp_ttype t;
+
+ if (c_lex (&oldname) != CPP_NAME)
+ {
+ warning ("malformed #pragma redefine_extname, ignored");
+ return;
+ }
+ if (c_lex (&newname) != CPP_NAME)
+ {
+ warning ("malformed #pragma redefine_extname, ignored");
+ return;
+ }
+ t = c_lex (&x);
+ if (t != CPP_EOF)
+ warning ("junk at end of #pragma redefine_extname");
+
+ decl = identifier_global_value (oldname);
+ if (decl && TREE_CODE_CLASS (TREE_CODE (decl)) == 'd')
+ {
+ if (DECL_ASSEMBLER_NAME_SET_P (decl)
+ && DECL_ASSEMBLER_NAME (decl) != newname)
+ warning ("#pragma redefine_extname conflicts with declaration");
+ SET_DECL_ASSEMBLER_NAME (decl, newname);
+ }
+ else
+ pending_redefine_extname
+ = tree_cons (oldname, newname, pending_redefine_extname);
+}
+#endif
+
+#ifdef HANDLE_PRAGMA_EXTERN_PREFIX
+static void handle_pragma_extern_prefix PARAMS ((cpp_reader *));
+
+static tree pragma_extern_prefix;
+
+/* #pragma extern_prefix "prefix" */
+static void
+handle_pragma_extern_prefix (dummy)
+ cpp_reader *dummy ATTRIBUTE_UNUSED;
+{
+ tree prefix, x;
+ enum cpp_ttype t;
+
+ if (c_lex (&prefix) != CPP_STRING)
+ {
+ warning ("malformed #pragma extern_prefix, ignored");
+ return;
+ }
+ t = c_lex (&x);
+ if (t != CPP_EOF)
+ warning ("junk at end of #pragma extern_prefix");
+
+ /* Note that the length includes the null terminator. */
+ pragma_extern_prefix = (TREE_STRING_LENGTH (prefix) > 1 ? prefix : NULL);
+}
+#endif
+
+/* Hook from the front ends to apply the results of one of the preceeding
+ pragmas that rename variables. */
+
+tree
+maybe_apply_renaming_pragma (decl, asmname)
+ tree decl, asmname;
+{
+ tree oldname;
+
+ /* Copied from the check in set_decl_assembler_name. */
+ if (TREE_CODE (decl) == FUNCTION_DECL
+ || (TREE_CODE (decl) == VAR_DECL
+ && (TREE_STATIC (decl)
+ || DECL_EXTERNAL (decl)
+ || TREE_PUBLIC (decl))))
+ oldname = DECL_ASSEMBLER_NAME (decl);
+ else
+ return asmname;
+
+ /* If the name begins with a *, that's a sign of an asmname attached to
+ a previous declaration. */
+ if (IDENTIFIER_POINTER (oldname)[0] == '*')
+ {
+ const char *oldasmname = IDENTIFIER_POINTER (oldname) + 1;
+ if (asmname && strcmp (TREE_STRING_POINTER (asmname), oldasmname) != 0)
+ warning ("asm declaration conficts with previous rename");
+ asmname = build_string (strlen (oldasmname), oldasmname);
+ }
+
+#ifdef HANDLE_PRAGMA_REDEFINE_EXTNAME
+ {
+ tree *p, t;
+
+ for (p = &pending_redefine_extname; (t = *p) ; p = &TREE_CHAIN (t))
+ if (oldname == TREE_PURPOSE (t))
{
- align = 0;
- state = ps_right;
+ const char *newname = IDENTIFIER_POINTER (TREE_VALUE (t));
+
+ if (asmname && strcmp (TREE_STRING_POINTER (asmname), newname) != 0)
+ warning ("#pragma redefine_extname conflicts with declaration");
+ *p = TREE_CHAIN (t);
+
+ return build_string (strlen (newname), newname);
}
- else
- state = ps_bad;
- break;
+ }
+#endif
- case ps_align:
- if (strcmp (string, ")") == 0)
- state = ps_right;
- else
- state = ps_bad;
- break;
+#ifdef HANDLE_PRAGMA_EXTERN_PREFIX
+ if (pragma_extern_prefix && !asmname)
+ {
+ char *x = concat (TREE_STRING_POINTER (pragma_extern_prefix),
+ IDENTIFIER_POINTER (oldname), NULL);
+ asmname = build_string (strlen (x), x);
+ free (x);
+ return asmname;
+ }
+#endif
+
+ return asmname;
+}
- case ps_right:
- state = ps_bad;
- break;
+void
+init_pragma ()
+{
+#ifdef HANDLE_PRAGMA_PACK
+ cpp_register_pragma (parse_in, 0, "pack", handle_pragma_pack);
+#endif
+#ifdef HANDLE_PRAGMA_WEAK
+ cpp_register_pragma (parse_in, 0, "weak", handle_pragma_weak);
+ ggc_add_tree_root (&pending_weaks, 1);
+#endif
+#ifdef HANDLE_PRAGMA_REDEFINE_EXTNAME
+ cpp_register_pragma (parse_in, 0, "redefine_extname",
+ handle_pragma_redefine_extname);
+ ggc_add_tree_root (&pending_redefine_extname, 1);
+#endif
+#ifdef HANDLE_PRAGMA_EXTERN_PREFIX
+ cpp_register_pragma (parse_in, 0, "extern_prefix",
+ handle_pragma_extern_prefix);
+ ggc_add_tree_root (&pragma_extern_prefix, 1);
+#endif
- case ps_bad:
- case ps_done:
- break;
+#ifdef REGISTER_TARGET_PRAGMAS
+ REGISTER_TARGET_PRAGMAS (parse_in);
+#endif
- default:
- abort ();
- }
+#ifdef HANDLE_PRAGMA_PACK_PUSH_POP
+ ggc_add_root (&alignment_stack, 1, sizeof(alignment_stack),
+ mark_align_stack);
+#endif
}
-#endif /* HANDLE_SYSV_PRAGMA */
OSDN Git Service
