523 lines
14 KiB
C
523 lines
14 KiB
C
/* obj-evax.c - EVAX (openVMS/Alpha) object file format.
|
|
Copyright (C) 1996-2016 Free Software Foundation, Inc.
|
|
Contributed by Klaus Kämpf (kkaempf@progis.de) of
|
|
proGIS Software, Aachen, Germany.
|
|
Extensively enhanced by Douglas Rupp of AdaCore.
|
|
|
|
This file is part of GAS, the GNU Assembler
|
|
|
|
GAS 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 3, or (at your option)
|
|
any later version.
|
|
|
|
GAS 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 GAS; see the file COPYING. If not, write to
|
|
the Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
|
|
MA 02110-1301, USA. */
|
|
|
|
#define OBJ_HEADER "obj-evax.h"
|
|
|
|
#include "as.h"
|
|
#include "bfd.h"
|
|
#include "vms.h"
|
|
#include "subsegs.h"
|
|
#include "struc-symbol.h"
|
|
#include "safe-ctype.h"
|
|
|
|
static void s_evax_weak (int);
|
|
static unsigned int crc32 (unsigned char *, int);
|
|
static char *encode_32 (unsigned int);
|
|
static char *encode_16 (unsigned int);
|
|
static int decode_16 (const char *);
|
|
|
|
const pseudo_typeS obj_pseudo_table[] =
|
|
{
|
|
{ "weak", s_evax_weak, 0},
|
|
{0, 0, 0},
|
|
}; /* obj_pseudo_table */
|
|
|
|
void obj_read_begin_hook () {}
|
|
|
|
/* Handle the weak specific pseudo-op. */
|
|
|
|
static void
|
|
s_evax_weak (int ignore ATTRIBUTE_UNUSED)
|
|
{
|
|
char *name;
|
|
int c;
|
|
symbolS *symbolP;
|
|
char *stop = NULL;
|
|
char stopc;
|
|
|
|
if (flag_mri)
|
|
stop = mri_comment_field (&stopc);
|
|
|
|
do
|
|
{
|
|
c = get_symbol_name (&name);
|
|
symbolP = symbol_find_or_make (name);
|
|
(void) restore_line_pointer (c);
|
|
SKIP_WHITESPACE ();
|
|
S_SET_WEAK (symbolP);
|
|
if (c == ',')
|
|
{
|
|
input_line_pointer++;
|
|
SKIP_WHITESPACE ();
|
|
if (*input_line_pointer == '\n')
|
|
c = '\n';
|
|
}
|
|
}
|
|
while (c == ',');
|
|
|
|
if (flag_mri)
|
|
mri_comment_end (stop, stopc);
|
|
|
|
demand_empty_rest_of_line ();
|
|
}
|
|
|
|
void
|
|
evax_symbol_new_hook (symbolS *sym)
|
|
{
|
|
struct evax_private_udata_struct *udata;
|
|
|
|
udata = (struct evax_private_udata_struct *)
|
|
xmalloc (sizeof (struct evax_private_udata_struct));
|
|
|
|
udata->bsym = symbol_get_bfdsym (sym);
|
|
udata->enbsym = NULL;
|
|
udata->origname = xstrdup (S_GET_NAME (sym));
|
|
udata->lkindex = 0;
|
|
symbol_get_bfdsym(sym)->udata.p = (PTR) udata;
|
|
}
|
|
|
|
void
|
|
evax_frob_symbol (symbolS *sym, int *punt)
|
|
{
|
|
const char *symname = S_GET_NAME (sym);
|
|
int symlen = strlen (symname);
|
|
asymbol *symbol = symbol_get_bfdsym (sym);
|
|
|
|
if (symlen > 4
|
|
&& strcmp (symname + symlen - 4, "..en") == 0
|
|
&& S_GET_SEGMENT (sym) == undefined_section)
|
|
{
|
|
symbol_clear_used_in_reloc (sym);
|
|
*punt = 1;
|
|
}
|
|
|
|
else if ((symbol->flags & BSF_GLOBAL) && (symbol->flags & BSF_FUNCTION))
|
|
{
|
|
struct evax_private_udata_struct *udata
|
|
= (struct evax_private_udata_struct *)symbol->udata.p;
|
|
|
|
/* Fix up equates of function definitions. */
|
|
while (udata->enbsym == NULL)
|
|
{
|
|
/* ??? Equates have been resolved at this point so their
|
|
expression is O_constant; but they previously were
|
|
O_symbol and we hope the equated symbol is still there. */
|
|
sym = symbol_get_value_expression (sym)->X_add_symbol;
|
|
if (sym == NULL)
|
|
{
|
|
as_bad (_("no entry symbol for global function '%s'"), symname);
|
|
return;
|
|
}
|
|
symbol = symbol_get_bfdsym (sym);
|
|
udata->enbsym
|
|
= ((struct evax_private_udata_struct *)symbol->udata.p)->enbsym;
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
evax_frob_file_before_adjust (void)
|
|
{
|
|
struct alpha_linkage_fixups *l;
|
|
segT current_section = now_seg;
|
|
int current_subsec = now_subseg;
|
|
segment_info_type *seginfo;
|
|
int linkage_index = 1;
|
|
|
|
subseg_set (alpha_link_section, 0);
|
|
seginfo = seg_info (alpha_link_section);
|
|
|
|
/* Handle .linkage fixups. */
|
|
for (l = alpha_linkage_fixup_root; l != NULL; l = l->next)
|
|
{
|
|
if (S_GET_SEGMENT (l->fixp->fx_addsy) == alpha_link_section)
|
|
{
|
|
/* The symbol is defined in the file. The linkage entry decays to
|
|
two relocs. */
|
|
symbolS *entry_sym;
|
|
fixS *fixpentry, *fixppdesc, *fixtail;
|
|
|
|
fixtail = seginfo->fix_tail;
|
|
|
|
/* Replace the linkage with the local symbols */
|
|
entry_sym = symbol_find
|
|
(((struct evax_private_udata_struct *)symbol_get_bfdsym (l->fixp->fx_addsy)->udata.p)->enbsym->name);
|
|
if (!entry_sym)
|
|
abort ();
|
|
fixpentry = fix_new (l->fixp->fx_frag, l->fixp->fx_where, 8,
|
|
entry_sym, l->fixp->fx_offset, 0,
|
|
BFD_RELOC_64);
|
|
fixppdesc = fix_new (l->fixp->fx_frag, l->fixp->fx_where + 8, 8,
|
|
l->fixp->fx_addsy, l->fixp->fx_offset, 0,
|
|
BFD_RELOC_64);
|
|
l->fixp->fx_size = 0;
|
|
l->fixp->fx_done = 1;
|
|
|
|
/* If not already at the tail, splice the new fixups into
|
|
the chain right after the one we are nulling out */
|
|
if (fixtail != l->fixp)
|
|
{
|
|
fixppdesc->fx_next = l->fixp->fx_next;
|
|
l->fixp->fx_next = fixpentry;
|
|
fixtail->fx_next = 0;
|
|
seginfo->fix_tail = fixtail;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* Assign a linkage index. */
|
|
((struct evax_private_udata_struct *)
|
|
symbol_get_bfdsym (l->label)->udata.p)->lkindex = linkage_index;
|
|
|
|
l->fixp->fx_addnumber = linkage_index;
|
|
|
|
linkage_index += 2;
|
|
}
|
|
}
|
|
|
|
subseg_set (current_section, current_subsec);
|
|
}
|
|
|
|
void
|
|
evax_frob_file_before_fix (void)
|
|
{
|
|
/* Now that the fixups are done earlier, we need to transfer the values
|
|
into the BFD symbols before calling fix_segment (ideally should not
|
|
be done also later). */
|
|
if (symbol_rootP)
|
|
{
|
|
symbolS *symp;
|
|
|
|
/* Set the value into the BFD symbol. Up til now the value
|
|
has only been kept in the gas symbolS struct. */
|
|
for (symp = symbol_rootP; symp; symp = symbol_next (symp))
|
|
symbol_get_bfdsym (symp)->value = S_GET_VALUE (symp);
|
|
}
|
|
}
|
|
|
|
/* The length is computed from the maximum allowable length of 64 less the
|
|
4 character ..xx extension that must be preserved (removed before
|
|
krunching and appended back on afterwards). The $<nnn>.. prefix is
|
|
also removed and prepened back on, but doesn't enter into the length
|
|
computation because symbols with that prefix are always resolved
|
|
by the assembler and will never appear in the symbol table. At least
|
|
I hope that's true, TBD. */
|
|
#define MAX_LABEL_LENGTH 60
|
|
|
|
static char *shorten_identifier (char *);
|
|
static int is_truncated_identifier (char *);
|
|
|
|
char *
|
|
evax_shorten_name (char *id)
|
|
{
|
|
int prefix_dotdot = 0;
|
|
char prefix [64];
|
|
int len = strlen (id);
|
|
int suffix_dotdot = len;
|
|
char suffix [64];
|
|
char *base_id;
|
|
|
|
/* This test may be too conservative. */
|
|
if (len <= MAX_LABEL_LENGTH)
|
|
return id;
|
|
|
|
suffix [0] = 0;
|
|
prefix [0] = 0;
|
|
|
|
/* Check for ..xx suffix and save it. */
|
|
if (strncmp (&id[len-4], "..", 2) == 0)
|
|
{
|
|
suffix_dotdot = len - 4;
|
|
strncpy (suffix, &id[len-4], 4);
|
|
suffix [4] = 0;
|
|
}
|
|
|
|
/* Check for $<nnn>.. prefix and save it. */
|
|
if ((id[0] == '$') && ISDIGIT (id[1]))
|
|
{
|
|
int i;
|
|
|
|
for (i=2; i < len; i++)
|
|
{
|
|
if (!ISDIGIT (id[i]))
|
|
{
|
|
if (id[i] == '.' && id [i+1] == '.')
|
|
{
|
|
prefix_dotdot = i+2;
|
|
strncpy (prefix, id, prefix_dotdot);
|
|
prefix [prefix_dotdot] = 0;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* We only need worry about krunching the base symbol. */
|
|
base_id = xmalloc (suffix_dotdot - prefix_dotdot + 1);
|
|
strncpy (base_id, &id[prefix_dotdot], suffix_dotdot - prefix_dotdot);
|
|
base_id [suffix_dotdot - prefix_dotdot] = 0;
|
|
|
|
if (strlen (base_id) > MAX_LABEL_LENGTH)
|
|
{
|
|
char new_id [4096];
|
|
char *return_id;
|
|
|
|
strcpy (new_id, base_id);
|
|
|
|
/* Shorten it. */
|
|
strcpy (new_id, shorten_identifier (new_id));
|
|
|
|
/* Prepend back the prefix if there was one. */
|
|
if (prefix_dotdot)
|
|
{
|
|
memmove (&new_id [prefix_dotdot], new_id, strlen (new_id) + 1);
|
|
strncpy (new_id, prefix, prefix_dotdot);
|
|
}
|
|
|
|
/* Append back the suffix if there was one. */
|
|
if (strlen (suffix))
|
|
strcat (new_id, suffix);
|
|
|
|
/* Save it on the heap and return. */
|
|
return_id = xmalloc (strlen (new_id) + 1);
|
|
strcpy (return_id, new_id);
|
|
|
|
return return_id;
|
|
}
|
|
else
|
|
return id;
|
|
}
|
|
|
|
/* The code below implements a mechanism for truncating long
|
|
identifiers to an arbitrary length (set by MAX_LABEL_LENGTH).
|
|
|
|
It attempts to make each truncated identifier unique by replacing
|
|
part of the identifier with an encoded 32-bit CRC and an associated
|
|
checksum (the checksum is used as a way to determine that the name
|
|
was truncated).
|
|
|
|
Note that both a portion of the start and of the end of the
|
|
identifier may be kept. The macro ID_SUFFIX_LENGTH will return the
|
|
number of characters in the suffix of the identifier that should be
|
|
kept.
|
|
|
|
The portion of the identifier that is going to be removed is
|
|
checksummed. The checksum is then encoded as a 5-character string,
|
|
the characters of which are then summed. This sum is then encoded
|
|
as a 3-character string. Finally, the original length of the
|
|
identifier is encoded as a 3-character string.
|
|
|
|
These three strings are then concatenated together (along with an _h
|
|
which further designates that the name was truncated):
|
|
|
|
"original_identifier"_haaaaabbbccc
|
|
|
|
aaaaa = 32-bit CRC
|
|
bbb = length of original identifier
|
|
ccc = sum of 32-bit CRC characters
|
|
|
|
The resulting identifier will be MAX_LABEL_LENGTH characters long.
|
|
|
|
*/
|
|
|
|
|
|
/* Table used to convert an integer into a string. */
|
|
|
|
static const char codings[] = {
|
|
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o',
|
|
'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
|
|
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O',
|
|
'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
|
|
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '_'};
|
|
|
|
/* The number of codings in the above table. */
|
|
static const int number_of_codings = sizeof (codings) / sizeof (char);
|
|
|
|
/* Table used by decode_16 () to convert an encoded string back into
|
|
an integer. */
|
|
static char decodings[256];
|
|
|
|
/* Table used by the crc32 function to calcuate the checksum. */
|
|
static unsigned int crc32_table[256] = {0, 0};
|
|
|
|
/* Given a string in BUF, calculate a 32-bit CRC for it.
|
|
|
|
This is used as a reasonably unique hash for the given string. */
|
|
|
|
static unsigned int
|
|
crc32 (unsigned char *buf, int len)
|
|
{
|
|
unsigned int crc = 0xffffffff;
|
|
|
|
if (! crc32_table[1])
|
|
{
|
|
/* Initialize the CRC table and the decoding table. */
|
|
int i, j;
|
|
unsigned int c;
|
|
|
|
for (i = 0; i < 256; i++)
|
|
{
|
|
for (c = i << 24, j = 8; j > 0; --j)
|
|
c = c & 0x80000000 ? (c << 1) ^ 0x04c11db7 : (c << 1);
|
|
crc32_table[i] = c;
|
|
decodings[i] = 0;
|
|
}
|
|
for (i = 0; i < number_of_codings; i++)
|
|
decodings[codings[i] & 255] = i;
|
|
}
|
|
|
|
while (len--)
|
|
{
|
|
crc = (crc << 8) ^ crc32_table[(crc >> 24) ^ *buf];
|
|
buf++;
|
|
}
|
|
return crc;
|
|
}
|
|
|
|
/* Encode the lower 32 bits of VALUE as a 5-character string. */
|
|
|
|
static char *
|
|
encode_32 (unsigned int value)
|
|
{
|
|
static char res[6];
|
|
int x;
|
|
|
|
res[5] = 0;
|
|
for(x = 0; x < 5; x++)
|
|
{
|
|
res[x] = codings[value % number_of_codings];
|
|
value = value / number_of_codings;
|
|
}
|
|
return res;
|
|
}
|
|
|
|
/* Encode the lower 16 bits of VALUE as a 3-character string. */
|
|
|
|
static char *
|
|
encode_16 (unsigned int value)
|
|
{
|
|
static char res[4];
|
|
int x;
|
|
|
|
res[3] = 0;
|
|
for(x = 0; x < 3; x++)
|
|
{
|
|
res[x] = codings[value % number_of_codings];
|
|
value = value / number_of_codings;
|
|
}
|
|
return res;
|
|
}
|
|
|
|
/* Convert the encoded string obtained from encode_16 () back into a
|
|
16-bit integer. */
|
|
|
|
static int
|
|
decode_16 (const char *string)
|
|
{
|
|
return decodings[(int) string[2]] * number_of_codings * number_of_codings
|
|
+ decodings[(int) string[1]] * number_of_codings
|
|
+ decodings[(int) string[0]];
|
|
}
|
|
|
|
/* ID_SUFFIX_LENGTH is used to determine how many characters in the
|
|
suffix of the identifier are to be preserved, if any. */
|
|
|
|
#ifndef ID_SUFFIX_LENGTH
|
|
#define ID_SUFFIX_LENGTH(ID) (0)
|
|
#endif
|
|
|
|
/* Return a reasonably-unique version of NAME that is less than or
|
|
equal to MAX_LABEL_LENGTH characters long. The string returned from
|
|
this function may be a copy of NAME; the function will never
|
|
actually modify the contents of NAME. */
|
|
|
|
static char newname[MAX_LABEL_LENGTH + 1];
|
|
|
|
static char *
|
|
shorten_identifier (char *name)
|
|
{
|
|
int crc, len, sum, x, final_len;
|
|
char *crc_chars;
|
|
int suffix_length = ID_SUFFIX_LENGTH (name);
|
|
|
|
if ((len = strlen (name)) <= MAX_LABEL_LENGTH)
|
|
return name;
|
|
|
|
final_len = MAX_LABEL_LENGTH - 2 - 5 - 3 - 3 - suffix_length;
|
|
crc = crc32 ((unsigned char *)name + final_len,
|
|
len - final_len - suffix_length);
|
|
crc_chars = encode_32 (crc);
|
|
sum = 0;
|
|
for (x = 0; x < 5; x++)
|
|
sum += crc_chars [x];
|
|
strncpy (newname, name, final_len);
|
|
newname [MAX_LABEL_LENGTH] = 0;
|
|
/* Now append the suffix of the original identifier, if any. */
|
|
if (suffix_length)
|
|
strncpy (newname + MAX_LABEL_LENGTH - suffix_length,
|
|
name + len - suffix_length,
|
|
suffix_length);
|
|
strncpy (newname + final_len, "_h", 2);
|
|
strncpy (newname + final_len + 2 , crc_chars, 5);
|
|
strncpy (newname + final_len + 2 + 5, encode_16 (len), 3);
|
|
strncpy (newname + final_len + 2 + 5 + 3, encode_16 (sum), 3);
|
|
if (!is_truncated_identifier (newname))
|
|
abort ();
|
|
return newname;
|
|
}
|
|
|
|
/* Determine whether or not ID is a truncated identifier, and return a
|
|
non-zero value if it is. */
|
|
|
|
static int
|
|
is_truncated_identifier (char *id)
|
|
{
|
|
char *ptr;
|
|
int len = strlen (id);
|
|
/* If it's not exactly MAX_LABEL_LENGTH characters long, it can't be
|
|
a truncated identifier. */
|
|
if (len != MAX_LABEL_LENGTH)
|
|
return 0;
|
|
|
|
/* Start scanning backwards for a _h. */
|
|
len = len - 3 - 3 - 5 - 2;
|
|
ptr = id + len;
|
|
while (ptr >= id)
|
|
{
|
|
if (ptr[0] == '_' && ptr[1] == 'h')
|
|
{
|
|
/* Now see if the sum encoded in the identifer matches. */
|
|
int x, sum;
|
|
sum = 0;
|
|
for (x = 0; x < 5; x++)
|
|
sum += ptr[x + 2];
|
|
/* If it matches, this is probably a truncated identifier. */
|
|
if (sum == decode_16 (ptr + 5 + 2 + 3))
|
|
return 1;
|
|
}
|
|
ptr--;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* end of obj-evax.c */
|