1 /* BFD back-end for ns32k a.out-ish binaries.
2    Copyright 1990, 1991, 1992, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
3    2002, 2003, 2005, 2007 Free Software Foundation, Inc.
4    Contributed by Ian Dall (idall@eleceng.adelaide.edu.au).
5 
6    This file is part of BFD, the Binary File Descriptor library.
7 
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12 
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with this program; if not, write to the Free Software
20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21    MA 02110-1301, USA.  */
22 
23 #include "bfd.h"
24 #include "aout/aout64.h"
25 #include "ns32k.h"
26 
27 /* Do not "beautify" the CONCAT* macro args.  Traditional C will not
28    remove whitespace added here, and thus will fail to concatenate
29    the tokens.  */
30 #define MYNS(OP) CONCAT2 (ns32kaout_,OP)
31 
32 reloc_howto_type * MYNS (bfd_reloc_type_lookup) (bfd *, bfd_reloc_code_real_type);
33 reloc_howto_type * MYNS (bfd_reloc_name_lookup) (bfd *, const char *);
34 bfd_boolean        MYNS (write_object_contents) (bfd *);
35 
36 /* Avoid multiple definitions from aoutx if supporting
37    standard a.out format(s) as well as this one.  */
38 #define NAME(x,y) CONCAT3 (ns32kaout,_32_,y)
39 
40 void bfd_ns32k_arch (void);
41 
42 #include "libaout.h"
43 
44 #define MY(OP) MYNS (OP)
45 
46 #define MY_swap_std_reloc_in   MY (swap_std_reloc_in)
47 #define MY_swap_std_reloc_out  MY (swap_std_reloc_out)
48 
49 /* The ns32k series is ah, unusual, when it comes to relocation.
50    There are three storage methods for relocatable objects.  There
51    are displacements, immediate operands and ordinary twos complement
52    data. Of these, only the last fits into the standard relocation
53    scheme.  Immediate operands are stored huffman encoded and
54    immediate operands are stored big endian (where as the natural byte
55    order is little endian for this architecture).
56 
57    Note that the ns32k displacement storage method is orthogonal to
58    whether the relocation is pc relative or not. The "displacement"
59    storage scheme is used for essentially all address constants. The
60    displacement can be relative to zero (absolute displacement),
61    relative to the pc (pc relative), the stack pointer, the frame
62    pointer, the static base register and general purpose register etc.
63 
64    For example:
65 
66    sym1: .long .	 # pc relative 2's complement
67    sym1: .long foo	 # 2's complement not pc relative
68 
69    self:  movd @self, r0 # pc relative displacement
70           movd foo, r0   # non pc relative displacement
71 
72    self:  movd self, r0  # pc relative immediate
73           movd foo, r0   # non pc relative immediate
74 
75    In addition, for historical reasons the encoding of the relocation types
76    in the a.out format relocation entries is such that even the relocation
77    methods which are standard are not encoded the standard way.  */
78 
79 reloc_howto_type MY (howto_table)[] =
80 {
81   /* ns32k immediate operands.  */
82   HOWTO (BFD_RELOC_NS32K_IMM_8, 0, 0, 8, FALSE, 0, complain_overflow_signed,
83 	 _bfd_ns32k_reloc_imm, "NS32K_IMM_8",
84 	 TRUE, 0x000000ff,0x000000ff, FALSE),
85   HOWTO (BFD_RELOC_NS32K_IMM_16, 0, 1, 16, FALSE, 0, complain_overflow_signed,
86 	 _bfd_ns32k_reloc_imm,  "NS32K_IMM_16",
87 	 TRUE, 0x0000ffff,0x0000ffff, FALSE),
88   HOWTO (BFD_RELOC_NS32K_IMM_32, 0, 2, 32, FALSE, 0, complain_overflow_signed,
89 	 _bfd_ns32k_reloc_imm, "NS32K_IMM_32",
90 	 TRUE, 0xffffffff,0xffffffff, FALSE),
91   HOWTO (BFD_RELOC_NS32K_IMM_8_PCREL, 0, 0, 8, TRUE, 0, complain_overflow_signed,
92 	 _bfd_ns32k_reloc_imm, "PCREL_NS32K_IMM_8",
93 	 TRUE, 0x000000ff, 0x000000ff, FALSE),
94   HOWTO (BFD_RELOC_NS32K_IMM_16_PCREL, 0, 1, 16, TRUE, 0, complain_overflow_signed,
95 	 _bfd_ns32k_reloc_imm, "PCREL_NS32K_IMM_16",
96 	 TRUE, 0x0000ffff,0x0000ffff, FALSE),
97   HOWTO (BFD_RELOC_NS32K_IMM_32_PCREL, 0, 2, 32, TRUE, 0, complain_overflow_signed,
98 	 _bfd_ns32k_reloc_imm, "PCREL_NS32K_IMM_32",
99 	 TRUE, 0xffffffff,0xffffffff, FALSE),
100 
101   /* ns32k displacements.  */
102   HOWTO (BFD_RELOC_NS32K_DISP_8, 0, 0, 7, FALSE, 0, complain_overflow_signed,
103 	 _bfd_ns32k_reloc_disp, "NS32K_DISP_8",
104 	 TRUE, 0x000000ff,0x000000ff, FALSE),
105   HOWTO (BFD_RELOC_NS32K_DISP_16, 0, 1, 14, FALSE, 0, complain_overflow_signed,
106 	 _bfd_ns32k_reloc_disp, "NS32K_DISP_16",
107 	 TRUE, 0x0000ffff, 0x0000ffff, FALSE),
108   HOWTO (BFD_RELOC_NS32K_DISP_32, 0, 2, 30, FALSE, 0, complain_overflow_signed,
109 	 _bfd_ns32k_reloc_disp, "NS32K_DISP_32",
110 	 TRUE, 0xffffffff, 0xffffffff, FALSE),
111   HOWTO (BFD_RELOC_NS32K_DISP_8_PCREL, 0, 0, 7, TRUE, 0, complain_overflow_signed,
112 	   _bfd_ns32k_reloc_disp, "PCREL_NS32K_DISP_8",
113 	 TRUE, 0x000000ff,0x000000ff, FALSE),
114   HOWTO (BFD_RELOC_NS32K_DISP_16_PCREL, 0, 1, 14, TRUE, 0, complain_overflow_signed,
115 	 _bfd_ns32k_reloc_disp, "PCREL_NS32K_DISP_16",
116 	 TRUE, 0x0000ffff,0x0000ffff, FALSE),
117   HOWTO (BFD_RELOC_NS32K_DISP_32_PCREL, 0, 2, 30, TRUE, 0, complain_overflow_signed,
118 	 _bfd_ns32k_reloc_disp, "PCREL_NS32K_DISP_32",
119 	 TRUE, 0xffffffff,0xffffffff, FALSE),
120 
121   /* Normal 2's complement.  */
122   HOWTO (BFD_RELOC_8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield,0,
123 	 "8", TRUE, 0x000000ff,0x000000ff, FALSE),
124   HOWTO (BFD_RELOC_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,0,
125 	 "16", TRUE, 0x0000ffff,0x0000ffff, FALSE),
126   HOWTO (BFD_RELOC_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,0,
127 	 "32", TRUE, 0xffffffff,0xffffffff, FALSE),
128   HOWTO (BFD_RELOC_8_PCREL, 0, 0, 8, TRUE, 0, complain_overflow_signed, 0,
129 	 "PCREL_8", TRUE, 0x000000ff,0x000000ff, FALSE),
130   HOWTO (BFD_RELOC_16_PCREL, 0, 1, 16, TRUE, 0, complain_overflow_signed, 0,
131 	 "PCREL_16", TRUE, 0x0000ffff,0x0000ffff, FALSE),
132   HOWTO (BFD_RELOC_32_PCREL, 0, 2, 32, TRUE, 0, complain_overflow_signed, 0,
133 	 "PCREL_32", TRUE, 0xffffffff,0xffffffff, FALSE),
134 };
135 
136 #define CTOR_TABLE_RELOC_HOWTO(BFD) (MY (howto_table) + 14)
137 
138 #define RELOC_STD_BITS_NS32K_TYPE_BIG 		0x06
139 #define RELOC_STD_BITS_NS32K_TYPE_LITTLE 	0x60
140 #define RELOC_STD_BITS_NS32K_TYPE_SH_BIG 	1
141 #define RELOC_STD_BITS_NS32K_TYPE_SH_LITTLE 	5
142 
143 static reloc_howto_type *
144 MY (reloc_howto) (bfd *abfd ATTRIBUTE_UNUSED,
145 		  struct reloc_std_external *rel,
146 		  int *r_index,
147 		  int *r_extern,
148 		  int *r_pcrel)
149 {
150   unsigned int r_length;
151   int r_ns32k_type;
152 
153   *r_index =  ((rel->r_index[2] << 16)
154 	       | (rel->r_index[1] << 8)
155 	       |  rel->r_index[0] );
156   *r_extern  = (0 != (rel->r_type[0] & RELOC_STD_BITS_EXTERN_LITTLE));
157   *r_pcrel   = (0 != (rel->r_type[0] & RELOC_STD_BITS_PCREL_LITTLE));
158   r_length  =  ((rel->r_type[0] & RELOC_STD_BITS_LENGTH_LITTLE)
159 		>> RELOC_STD_BITS_LENGTH_SH_LITTLE);
160   r_ns32k_type  =  ((rel->r_type[0] & RELOC_STD_BITS_NS32K_TYPE_LITTLE)
161 		    >> RELOC_STD_BITS_NS32K_TYPE_SH_LITTLE);
162   return (MY (howto_table) + r_length + 3 * (*r_pcrel) + 6 * r_ns32k_type);
163 }
164 
165 #define MY_reloc_howto(BFD, REL, IN, EX, PC) \
166   MY (reloc_howto) (BFD, REL, &IN, &EX, &PC)
167 
168 static void
169 MY (put_reloc) (bfd *abfd,
170 		int r_extern,
171 		int r_index,
172 		bfd_vma value,
173 		reloc_howto_type *howto,
174 		struct reloc_std_external *reloc)
175 {
176   unsigned int r_length;
177   int r_pcrel;
178   int r_ns32k_type;
179 
180   PUT_WORD (abfd, value, reloc->r_address);
181   r_length = howto->size ;	/* Size as a power of two.  */
182   r_pcrel  = (int) howto->pc_relative; /* Relative to PC?  */
183   r_ns32k_type = (howto - MY (howto_table) )/6;
184 
185   reloc->r_index[2] = r_index >> 16;
186   reloc->r_index[1] = r_index >> 8;
187   reloc->r_index[0] = r_index;
188   reloc->r_type[0] =
189     (r_extern?    RELOC_STD_BITS_EXTERN_LITTLE: 0)
190       | (r_pcrel?     RELOC_STD_BITS_PCREL_LITTLE: 0)
191 	| (r_length <<  RELOC_STD_BITS_LENGTH_SH_LITTLE)
192 	  | (r_ns32k_type <<  RELOC_STD_BITS_NS32K_TYPE_SH_LITTLE);
193 }
194 
195 #define MY_put_reloc(BFD, EXT, IDX, VAL, HOWTO, RELOC) \
196   MY (put_reloc) (BFD, EXT, IDX, VAL, HOWTO, RELOC)
197 
198 #define STAT_FOR_EXEC
199 
200 #define MY_final_link_relocate _bfd_ns32k_final_link_relocate
201 #define MY_relocate_contents   _bfd_ns32k_relocate_contents
202 
203 static void MY_swap_std_reloc_in (bfd *, struct reloc_std_external *, arelent *, asymbol **, bfd_size_type);
204 static void MY_swap_std_reloc_out (bfd *, arelent *, struct reloc_std_external *);
205 
206 #include "aoutx.h"
207 
208 reloc_howto_type *
209 MY (bfd_reloc_type_lookup) (bfd *abfd, bfd_reloc_code_real_type code)
210 {
211 #define ENTRY(i,j)	case i: return &MY (howto_table)[j]
212 
213   int ext = obj_reloc_entry_size (abfd) == RELOC_EXT_SIZE;
214 
215   BFD_ASSERT (ext == 0);
216   if (code == BFD_RELOC_CTOR)
217     switch (bfd_get_arch_info (abfd)->bits_per_address)
218       {
219       case 32:
220 	code = BFD_RELOC_32;
221 	break;
222       default:
223 	break;
224       }
225   switch (code)
226     {
227       ENTRY (BFD_RELOC_NS32K_IMM_8, 0);
228       ENTRY (BFD_RELOC_NS32K_IMM_16, 1);
229       ENTRY (BFD_RELOC_NS32K_IMM_32, 2);
230       ENTRY (BFD_RELOC_NS32K_IMM_8_PCREL, 3);
231       ENTRY (BFD_RELOC_NS32K_IMM_16_PCREL, 4);
232       ENTRY (BFD_RELOC_NS32K_IMM_32_PCREL, 5);
233       ENTRY (BFD_RELOC_NS32K_DISP_8, 6);
234       ENTRY (BFD_RELOC_NS32K_DISP_16, 7);
235       ENTRY (BFD_RELOC_NS32K_DISP_32, 8);
236       ENTRY (BFD_RELOC_NS32K_DISP_8_PCREL, 9);
237       ENTRY (BFD_RELOC_NS32K_DISP_16_PCREL, 10);
238       ENTRY (BFD_RELOC_NS32K_DISP_32_PCREL, 11);
239       ENTRY (BFD_RELOC_8, 12);
240       ENTRY (BFD_RELOC_16, 13);
241       ENTRY (BFD_RELOC_32, 14);
242       ENTRY (BFD_RELOC_8_PCREL, 15);
243       ENTRY (BFD_RELOC_16_PCREL, 16);
244       ENTRY (BFD_RELOC_32_PCREL, 17);
245     default:
246       return NULL;
247     }
248 #undef ENTRY
249 }
250 
251 reloc_howto_type *
252 MY (bfd_reloc_name_lookup) (bfd *abfd ATTRIBUTE_UNUSED,
253 			    const char *r_name)
254 {
255   unsigned int i;
256 
257   for (i = 0;
258        i < sizeof (MY (howto_table)) / sizeof (MY (howto_table)[0]);
259        i++)
260     if (MY (howto_table)[i].name != NULL
261 	&& strcasecmp (MY (howto_table)[i].name, r_name) == 0)
262       return &MY (howto_table)[i];
263 
264   return NULL;
265 }
266 
267 static void
268 MY_swap_std_reloc_in (bfd *abfd,
269 		      struct reloc_std_external *bytes,
270 		      arelent *cache_ptr,
271 		      asymbol **symbols,
272 		      bfd_size_type symcount ATTRIBUTE_UNUSED)
273 {
274   int r_index;
275   int r_extern;
276   int r_pcrel;
277   struct aoutdata  *su = &(abfd->tdata.aout_data->a);
278 
279   cache_ptr->address = H_GET_32 (abfd, bytes->r_address);
280 
281   /* Now the fun stuff.  */
282   cache_ptr->howto = MY_reloc_howto (abfd, bytes, r_index, r_extern, r_pcrel);
283 
284   MOVE_ADDRESS (0);
285 }
286 
287 static void
288 MY_swap_std_reloc_out (bfd *abfd,
289 		       arelent *g,
290 		       struct reloc_std_external *natptr)
291 {
292   int r_index;
293   asymbol *sym = *(g->sym_ptr_ptr);
294   int r_extern;
295   asection *output_section = sym->section->output_section;
296 
297   /* Name was clobbered by aout_write_syms to be symbol index.  */
298 
299   /* If this relocation is relative to a symbol then set the
300      r_index to the symbols index, and the r_extern bit.
301 
302      Absolute symbols can come in in two ways, either as an offset
303      from the abs section, or as a symbol which has an abs value.
304      Check for that here.  */
305   if (bfd_is_com_section (output_section)
306       || output_section == &bfd_abs_section
307       || output_section == &bfd_und_section)
308     {
309       if (bfd_abs_section.symbol == sym)
310 	{
311 	  /* Whoops, looked like an abs symbol, but is really an offset
312 	     from the abs section.  */
313 	  r_index = 0;
314 	  r_extern = 0;
315 	}
316       else
317 	{
318 	  /* Fill in symbol.  */
319 	  r_extern = 1;
320 #undef KEEPIT
321 #define KEEPIT udata.i
322 	  r_index =  (*(g->sym_ptr_ptr))->KEEPIT;
323 #undef KEEPIT
324 	}
325     }
326   else
327     {
328       /* Just an ordinary section.  */
329       r_extern = 0;
330       r_index  = output_section->target_index;
331     }
332 
333   MY_put_reloc (abfd, r_extern, r_index, g->address, g->howto, natptr);
334 }
335 
336 bfd_reloc_status_type
337 _bfd_ns32k_relocate_contents (reloc_howto_type *howto,
338 			      bfd *input_bfd,
339 			      bfd_vma relocation,
340 			      bfd_byte *location)
341 {
342   int r_ns32k_type = (howto - MY (howto_table)) / 6;
343   bfd_vma (*get_data) (bfd_byte *, int);
344   void (*put_data) (bfd_vma, bfd_byte *, int);
345 
346   switch (r_ns32k_type)
347     {
348     case 0:
349       get_data = _bfd_ns32k_get_immediate;
350       put_data = _bfd_ns32k_put_immediate;
351       break;
352     case 1:
353       get_data = _bfd_ns32k_get_displacement;
354       put_data = _bfd_ns32k_put_displacement;
355       break;
356     case 2:
357       return _bfd_relocate_contents (howto, input_bfd, relocation,
358 				    location);
359     default:
360       return bfd_reloc_notsupported;
361     }
362   return _bfd_do_ns32k_reloc_contents (howto, input_bfd, relocation,
363 				       location, get_data, put_data);
364 }
365