/* Handle #pragma, system V.4 style. Supports #pragma weak and #pragma pack.
- Copyright (C) 1992, 1997 Free Software Foundation, Inc.
+ Copyright (C) 1992, 1997, 1998 Free Software Foundation, Inc.
This file is part of GNU CC.
#include "config.h"
#include "system.h"
+#include "rtl.h"
#include "tree.h"
#include "except.h"
#include "function.h"
#include "flags.h"
#include "toplev.h"
-#ifdef HANDLE_SYSV_PRAGMA
+#ifdef HANDLE_GENERIC_PRAGMAS
+#ifdef HANDLE_PRAGMA_PACK
/* 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. */
extern int maximum_field_alignment;
+#endif
-/* File used for outputting assembler code. */
-extern FILE *asm_out_file;
-/* Handle one token of a pragma directive. TOKEN is the
- current token, and STRING is its printable form. */
+#ifdef HANDLE_PRAGMA_PACK_PUSH_POP
+typedef struct align_stack
+{
+ int alignment;
+ unsigned int num_pushes;
+ struct align_stack * prev;
+} align_stack;
+
+static struct align_stack * alignment_stack = NULL;
+
+static int push_alignment PROTO((int));
+static int pop_alignment PROTO((void));
+
+/* Push an alignment value onto the stack. */
+static int
+push_alignment (alignment)
+ int alignment;
+{
+ switch (alignment)
+ {
+ case 0:
+ case 1:
+ case 2:
+ case 4:
+ case 8:
+ case 16:
+ break;
+ default:
+ warning ("\
+Alignment must be a small power of two, not %d, in #pragma pack",
+ alignment);
+ return 0;
+ }
+
+ if (alignment_stack == NULL
+ || alignment_stack->alignment != alignment)
+ {
+ align_stack * entry;
+
+ entry = (align_stack *) xmalloc (sizeof (* entry));
+
+ if (entry == NULL)
+ {
+ warning ("Out of memory pushing #pragma pack");
+ return 0;
+ }
+
+ entry->alignment = alignment;
+ entry->num_pushes = 1;
+ entry->prev = alignment_stack;
+
+ alignment_stack = entry;
+
+ if (alignment < 8)
+ maximum_field_alignment = alignment * 8;
+ else
+ /* MSVC ignores alignments > 4. */
+ maximum_field_alignment = 0;
+ }
+ else
+ alignment_stack->num_pushes ++;
+
+ return 1;
+}
+
+/* Undo a push of an alignment onto the stack. */
+static int
+pop_alignment ()
+{
+ if (alignment_stack == NULL)
+ {
+ warning ("\
+#pragma pack(pop) encountered without corresponding #pragma pack(push,<n>)");
+ return 0;
+ }
+
+ if (-- alignment_stack->num_pushes == 0)
+ {
+ align_stack * entry;
+
+ entry = alignment_stack->prev;
+
+ if (entry == NULL || entry->alignment > 4)
+ maximum_field_alignment = 0;
+ else
+ maximum_field_alignment = entry->alignment * 8;
+ free (alignment_stack);
+
+ alignment_stack = entry;
+ }
+
+ return 1;
+}
+
+/* Generate 'packed' and 'aligned' attributes for decls whilst a
+ #pragma pack(push... is in effect. */
void
+insert_pack_attributes (node, attributes, prefix)
+ tree node;
+ tree * attributes;
+ tree * prefix;
+{
+ tree a;
+
+ /* If we are not packing, then there is nothing to do. */
+ if (maximum_field_alignment == 0
+ || alignment_stack == NULL)
+ return;
+
+ /* We are only interested in fields. */
+ if (TREE_CODE_CLASS (TREE_CODE (node)) != 'd'
+ || TREE_CODE (node) != FIELD_DECL)
+ return;
+
+ /* Add a 'packed' attribute. */
+ * attributes = tree_cons (get_identifier ("packed"), NULL, * attributes);
+
+ /* If the alignment is > 8 then add an alignment attribute as well. */
+ if (maximum_field_alignment > 8)
+ {
+ /* If the aligned attribute is already present then do not override it. */
+ for (a = * attributes; a; a = TREE_CHAIN (a))
+ {
+ tree name = TREE_PURPOSE (a);
+ if (strcmp (IDENTIFIER_POINTER (name), "aligned") == 0)
+ break;
+ }
+
+ if (a == NULL)
+ for (a = * prefix; a; a = TREE_CHAIN (a))
+ {
+ tree name = TREE_PURPOSE (a);
+ if (strcmp (IDENTIFIER_POINTER (name), "aligned") == 0)
+ break;
+ }
+
+ if (a == NULL)
+ {
+ * attributes = tree_cons
+ (get_identifier ("aligned"),
+ tree_cons (NULL,
+ build_int_2 (maximum_field_alignment / 8, 0),
+ NULL),
+ * attributes);
+ }
+ }
+
+ return;
+}
+#endif /* HANDLE_PRAGMA_PACK_PUSH_POP */
+\f
+#ifdef HANDLE_PRAGMA_WEAK
+static int add_weak PROTO((char *, char *));
+
+static int
+add_weak (name, value)
+ char * name;
+ char * value;
+{
+ struct weak_syms * weak;
+
+ weak = (struct weak_syms *) permalloc (sizeof (struct weak_syms));
+
+ if (weak == NULL)
+ return 0;
+
+ weak->next = weak_decls;
+ weak->name = name;
+ weak->value = value;
+ weak_decls = weak;
+
+ return 1;
+}
+#endif /* HANDLE_PRAGMA_WEAK */
+\f
+/* Handle one token of a pragma directive. TOKEN is the current token, and
+ STRING is its printable form. Some front ends do not support generating
+ tokens, and will only pass in a STRING. Also some front ends will reuse
+ the buffer containing STRING, so it must be copied to a local buffer if
+ it needs to be preserved.
+
+ If STRING is non-NULL, then the return value will be ignored, and there
+ will be futher calls to handle_pragma_token() in order to handle the rest of
+ the line containing the #pragma directive. If STRING is NULL, the entire
+ line has now been presented to handle_pragma_token() and the return value
+ should be zero if the pragma flawed in some way, or if the pragma was not
+ recognised, and non-zero if it was successfully handled. */
+
+int
handle_pragma_token (string, token)
- char *string;
+ char * string;
tree token;
{
- static enum pragma_state state = ps_start, type;
- static char *name;
- static char *value;
+ static enum pragma_state state = ps_start;
+ static enum pragma_state type;
+ static char * name;
+ static char * value;
static int align;
- if (string == 0)
+ /* If we have reached the end of the #pragma directive then
+ determine what value we should return. */
+
+ if (string == NULL)
{
- if (type == ps_pack)
+ int ret_val = 0;
+
+ switch (type)
{
+ default:
+ abort ();
+ break;
+
+ case ps_done:
+ /* The pragma was not recognised. */
+ break;
+
+#ifdef HANDLE_PRAGMA_PACK
+ case ps_pack:
if (state == ps_right)
- maximum_field_alignment = align * 8;
+ {
+ maximum_field_alignment = align * 8;
+ ret_val = 1;
+ }
else
warning ("malformed `#pragma pack'");
- }
- else if (type == ps_weak)
- {
+ break;
+#endif /* HANDLE_PRAGMA_PACK */
+
+#ifdef HANDLE_PRAGMA_PACK_PUSH_POP
+ case ps_push:
+ if (state == ps_right)
+ ret_val = push_alignment (align);
+ else
+ warning ("incomplete '#pragma pack(push,<n>)'");
+ break;
+
+ case ps_pop:
+ if (state == ps_right)
+ ret_val = pop_alignment ();
+ else
+ warning ("missing closing parenthesis in '#pragma pack(pop)'");
+ break;
+#endif /* HANDLE_PRAGMA_PACK_PUSH_POP */
+
#ifdef HANDLE_PRAGMA_WEAK
+ case ps_weak:
if (HANDLE_PRAGMA_WEAK)
- handle_pragma_weak (state, name, value);
-
+ {
+ if (state == ps_name)
+ ret_val = add_weak (name, NULL);
+ else if (state == ps_value)
+ ret_val = add_weak (name, value);
+ else
+ warning ("malformed `#pragma weak'");
+ }
+ else
+ ret_val = 1; /* Ignore the pragma. */
+ break;
#endif /* HANDLE_PRAGMA_WEAK */
}
type = state = ps_start;
- return;
+
+ return ret_val;
}
+ /* If we have been given a token, but it is not an identifier,
+ or a small constant, then something has gone wrong. */
+ if (token)
+ {
+ switch (TREE_CODE (token))
+ {
+ case IDENTIFIER_NODE:
+ break;
+
+ case INTEGER_CST:
+ if (TREE_INT_CST_HIGH (token) != 0)
+ return 0;
+ break;
+
+ default:
+ return 0;
+ }
+ }
+
switch (state)
{
case ps_start:
- if (token && TREE_CODE (token) == IDENTIFIER_NODE)
+ type = state = ps_done;
+#ifdef HANDLE_PRAGMA_PACK
+ if (strcmp (string, "pack") == 0)
+ type = state = ps_pack;
+#endif
+#ifdef HANDLE_PRAGMA_WEAK
+ if (strcmp (string, "weak") == 0)
+ type = state = ps_weak;
+#endif
+ break;
+
+#ifdef HANDLE_PRAGMA_WEAK
+ case ps_weak:
+ name = permalloc (strlen (string) + 1);
+ if (name == NULL)
{
- 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;
-
- /* Issue a warning message if we have been asked to do so.
- Ignoring unknown pragmas in system header file unless
- an explcit -Wunknown-pragmas has been given. */
- if (warn_unknown_pragmas > 1
- || (warn_unknown_pragmas && ! in_system_header))
- warning ("ignoring pragma: %s", string);
- }
+ warning ("Out of memory parsing #pragma weak");
+ state = ps_bad;
}
else
- type = state = ps_done;
- break;
-
- case ps_weak:
- if (token && TREE_CODE (token) == IDENTIFIER_NODE)
{
- name = IDENTIFIER_POINTER (token);
+ strcpy (name, string);
state = ps_name;
}
- else
- state = ps_bad;
break;
-
+
case ps_name:
state = (strcmp (string, "=") ? ps_bad : ps_equals);
break;
case ps_equals:
- if (token && TREE_CODE (token) == IDENTIFIER_NODE)
+ value = permalloc (strlen (string) + 1);
+ if (value == NULL)
{
- value = IDENTIFIER_POINTER (token);
- state = ps_value;
+ warning ("Out of memory parsing #pragma weak");
+ state = ps_bad;
}
else
- state = ps_bad;
+ {
+ strcpy (value, string);
+ state = ps_value;
+ }
break;
case ps_value:
state = ps_bad;
break;
-
+#endif /* HANDLE_PRAGMA_WEAK */
+
+#ifdef HANDLE_PRAGMA_PACK
case ps_pack:
- if (strcmp (string, "(") == 0)
- state = ps_left;
- else
- state = ps_bad;
+ state = (strcmp (string, "(") ? ps_bad : ps_left);
break;
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;
- default:
- state = ps_bad;
- }
- else if (! token && strcmp (string, ")") == 0)
+ if (token && TREE_CODE(token) == INTEGER_CST)
+ align = TREE_INT_CST_LOW(token);
+ else
+ align = atoi (string);
+ switch (align)
{
- align = 0;
- state = ps_right;
+ case 1:
+ case 2:
+ case 4:
+ state = ps_align;
+ break;
+
+ case 0:
+ state = (strcmp (string, ")") ? ps_bad : ps_right);
+#ifdef HANDLE_PRAGMA_PACK_PUSH_POP
+ if (state == ps_bad)
+ {
+ if (strcmp (string, "push") == 0)
+ type = state = ps_push;
+ else if (strcmp (string, "pop") == 0)
+ type = state = ps_pop;
+ }
+#endif
+ break;
+
+ default:
+ state = ps_bad;
+ break;
}
- else
- state = ps_bad;
break;
+#ifdef HANDLE_PRAGMA_PACK_PUSH_POP
+ case ps_pop:
+#endif
case ps_align:
- if (strcmp (string, ")") == 0)
- state = ps_right;
- else
- state = ps_bad;
+ state = (strcmp (string, ")") ? ps_bad : ps_right);
break;
case ps_right:
state = ps_bad;
break;
+#endif /* HANDLE_PRAGMA_PACK */
+
+#ifdef HANDLE_PRAGMA_PACK_PUSH_POP
+ case ps_push:
+ state = (strcmp (string, ",") ? ps_bad : ps_comma);
+ break;
+ case ps_comma:
+ align = atoi (string);
+ state = ps_align;
+ break;
+#endif /* HANDLE_PRAGMA_PACK_PUSH_POP */
+
case ps_bad:
case ps_done:
break;
default:
abort ();
}
+
+ return 1;
}
-#endif /* HANDLE_SYSV_PRAGMA */
+#endif /* HANDLE_GENERIC_PRAGMAS */
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