1 /* Generic ECOFF support.
2    This does not include symbol information, found in sym.h and
3    symconst.h.
4 
5    Copyright 2001, 2002, 2003 Free Software Foundation, Inc.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 2 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program; if not, write to the Free Software
19    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
20 
21 #ifndef ECOFF_H
22 #define ECOFF_H
23 
24 /* Mips magic numbers used in filehdr.  MIPS_MAGIC_LITTLE is used on
25    little endian machines.  MIPS_MAGIC_BIG is used on big endian
26    machines.  Where is MIPS_MAGIC_1 from?  */
27 #define MIPS_MAGIC_1 0x0180
28 #define MIPS_MAGIC_LITTLE 0x0162
29 #define MIPS_MAGIC_BIG 0x0160
30 
31 /* These are the magic numbers used for MIPS code compiled at ISA
32    level 2.  */
33 #define MIPS_MAGIC_LITTLE2 0x0166
34 #define MIPS_MAGIC_BIG2 0x0163
35 
36 /* These are the magic numbers used for MIPS code compiled at ISA
37    level 3.  */
38 #define MIPS_MAGIC_LITTLE3 0x142
39 #define MIPS_MAGIC_BIG3 0x140
40 
41 /* Alpha magic numbers used in filehdr.  */
42 #define ALPHA_MAGIC 0x183
43 #define ALPHA_MAGIC_BSD 0x185
44 
45 /* Magic numbers used in a.out header.  */
46 #define ECOFF_AOUT_OMAGIC 0407	/* not demand paged (ld -N).  */
47 #define ECOFF_AOUT_ZMAGIC 0413	/* demand load format, eg normal ld output */
48 
49 /* Names of special sections.  */
50 #define _TEXT   ".text"
51 #define _DATA   ".data"
52 #define _BSS    ".bss"
53 #define _RDATA	".rdata"
54 #define _SDATA	".sdata"
55 #define _SBSS	".sbss"
56 #define _LITA	".lita"
57 #define _LIT4	".lit4"
58 #define _LIT8	".lit8"
59 #define _LIB	".lib"
60 #define _INIT	".init"
61 #define _FINI	".fini"
62 #define _PDATA	".pdata"
63 #define _XDATA	".xdata"
64 #define _GOT	".got"
65 #define _HASH	".hash"
66 #define _DYNSYM	".dynsym"
67 #define _DYNSTR	".dynstr"
68 #define _RELDYN	".rel.dyn"
69 #define _CONFLIC ".conflic"
70 #define _COMMENT ".comment"
71 #define _LIBLIST ".liblist"
72 #define _DYNAMIC ".dynamic"
73 #define _RCONST	".rconst"
74 
75 /* ECOFF uses some additional section flags.  */
76 #define STYP_RDATA	     0x100
77 #define STYP_SDATA	     0x200
78 #define STYP_SBSS	     0x400
79 #define STYP_GOT	    0x1000
80 #define STYP_DYNAMIC	    0x2000
81 #define STYP_DYNSYM	    0x4000
82 #define STYP_RELDYN	    0x8000
83 #define STYP_DYNSTR	   0x10000
84 #define STYP_HASH	   0x20000
85 #define STYP_LIBLIST	   0x40000
86 #define STYP_CONFLIC	  0x100000
87 #define STYP_ECOFF_FINI	 0x1000000
88 #define STYP_EXTENDESC	 0x2000000 /* 0x02FFF000 bits => scn type, rest clr */
89 #define STYP_LITA	 0x4000000
90 #define STYP_LIT8	 0x8000000
91 #define STYP_LIT4	0x10000000
92 #define STYP_ECOFF_LIB	0x40000000
93 #define STYP_ECOFF_INIT 0x80000000
94 #define STYP_OTHER_LOAD (STYP_ECOFF_INIT | STYP_ECOFF_FINI)
95 
96 /* extended section types */
97 #define STYP_COMMENT	 0x2100000
98 #define STYP_RCONST	 0x2200000
99 #define STYP_XDATA	 0x2400000
100 #define STYP_PDATA	 0x2800000
101 
102 /* The linker needs a section to hold small common variables while
103    linking.  There is no convenient way to create it when the linker
104    needs it, so we always create one for each BFD.  We then avoid
105    writing it out.  */
106 #define SCOMMON ".scommon"
107 
108 /* If the extern bit in a reloc is 1, then r_symndx is an index into
109    the external symbol table.  If the extern bit is 0, then r_symndx
110    indicates a section, and is one of the following values.  */
111 #define RELOC_SECTION_NONE	0
112 #define RELOC_SECTION_TEXT	1
113 #define RELOC_SECTION_RDATA	2
114 #define RELOC_SECTION_DATA	3
115 #define RELOC_SECTION_SDATA	4
116 #define RELOC_SECTION_SBSS	5
117 #define RELOC_SECTION_BSS	6
118 #define RELOC_SECTION_INIT	7
119 #define RELOC_SECTION_LIT8	8
120 #define RELOC_SECTION_LIT4	9
121 #define RELOC_SECTION_XDATA    10
122 #define RELOC_SECTION_PDATA    11
123 #define RELOC_SECTION_FINI     12
124 #define RELOC_SECTION_LITA     13
125 #define RELOC_SECTION_ABS      14
126 #define RELOC_SECTION_RCONST   15
127 
128 #define NUM_RELOC_SECTIONS     16
129 
130 /********************** STABS **********************/
131 
132 /* gcc uses mips-tfile to output type information in special stabs
133    entries.  These must match the corresponding definition in
134    gcc/config/mips.h.  At some point, these should probably go into a
135    shared include file, but currently gcc and gdb do not share any
136    directories. */
137 #define CODE_MASK 0x8F300
138 #define ECOFF_IS_STAB(sym) (((sym)->index & 0xFFF00) == CODE_MASK)
139 #define ECOFF_MARK_STAB(code) ((code)+CODE_MASK)
140 #define ECOFF_UNMARK_STAB(code) ((code)-CODE_MASK)
141 #define STABS_SYMBOL "@stabs"
142 
143 /********************** COFF **********************/
144 
145 /* gcc also uses mips-tfile to output COFF debugging information.
146    These are the values it uses when outputting the .type directive.
147    These should also be in a shared include file.  */
148 #define N_BTMASK	(017)
149 #define N_TMASK		(060)
150 #define N_BTSHFT	(4)
151 #define N_TSHIFT	(2)
152 
153 /********************** AUX **********************/
154 
155 /* The auxiliary type information is the same on all known ECOFF
156    targets.  I can't see any reason that it would ever change, so I am
157    going to gamble and define the external structures here, in the
158    target independent ECOFF header file.  The internal forms are
159    defined in coff/sym.h, which was originally donated by MIPS
160    Computer Systems.  */
161 
162 /* Type information external record */
163 
164 struct tir_ext {
165 	unsigned char	t_bits1[1];
166 	unsigned char	t_tq45[1];
167 	unsigned char	t_tq01[1];
168 	unsigned char	t_tq23[1];
169 };
170 
171 #define	TIR_BITS1_FBITFIELD_BIG		((unsigned int) 0x80)
172 #define	TIR_BITS1_FBITFIELD_LITTLE	((unsigned int) 0x01)
173 
174 #define	TIR_BITS1_CONTINUED_BIG		((unsigned int) 0x40)
175 #define	TIR_BITS1_CONTINUED_LITTLE	((unsigned int) 0x02)
176 
177 #define	TIR_BITS1_BT_BIG		((unsigned int) 0x3F)
178 #define	TIR_BITS1_BT_SH_BIG		0
179 #define	TIR_BITS1_BT_LITTLE		((unsigned int) 0xFC)
180 #define	TIR_BITS1_BT_SH_LITTLE		2
181 
182 #define	TIR_BITS_TQ4_BIG		((unsigned int) 0xF0)
183 #define	TIR_BITS_TQ4_SH_BIG		4
184 #define	TIR_BITS_TQ5_BIG		((unsigned int) 0x0F)
185 #define	TIR_BITS_TQ5_SH_BIG		0
186 #define	TIR_BITS_TQ4_LITTLE		((unsigned int) 0x0F)
187 #define	TIR_BITS_TQ4_SH_LITTLE		0
188 #define	TIR_BITS_TQ5_LITTLE		((unsigned int) 0xF0)
189 #define	TIR_BITS_TQ5_SH_LITTLE		4
190 
191 #define	TIR_BITS_TQ0_BIG		((unsigned int) 0xF0)
192 #define	TIR_BITS_TQ0_SH_BIG		4
193 #define	TIR_BITS_TQ1_BIG		((unsigned int) 0x0F)
194 #define	TIR_BITS_TQ1_SH_BIG		0
195 #define	TIR_BITS_TQ0_LITTLE		((unsigned int) 0x0F)
196 #define	TIR_BITS_TQ0_SH_LITTLE		0
197 #define	TIR_BITS_TQ1_LITTLE		((unsigned int) 0xF0)
198 #define	TIR_BITS_TQ1_SH_LITTLE		4
199 
200 #define	TIR_BITS_TQ2_BIG		((unsigned int) 0xF0)
201 #define	TIR_BITS_TQ2_SH_BIG		4
202 #define	TIR_BITS_TQ3_BIG		((unsigned int) 0x0F)
203 #define	TIR_BITS_TQ3_SH_BIG		0
204 #define	TIR_BITS_TQ2_LITTLE		((unsigned int) 0x0F)
205 #define	TIR_BITS_TQ2_SH_LITTLE		0
206 #define	TIR_BITS_TQ3_LITTLE		((unsigned int) 0xF0)
207 #define	TIR_BITS_TQ3_SH_LITTLE		4
208 
209 /* Relative symbol external record */
210 
211 struct rndx_ext {
212 	unsigned char	r_bits[4];
213 };
214 
215 #define	RNDX_BITS0_RFD_SH_LEFT_BIG	4
216 #define	RNDX_BITS1_RFD_BIG		((unsigned int) 0xF0)
217 #define	RNDX_BITS1_RFD_SH_BIG		4
218 
219 #define	RNDX_BITS0_RFD_SH_LEFT_LITTLE	0
220 #define	RNDX_BITS1_RFD_LITTLE		((unsigned int) 0x0F)
221 #define	RNDX_BITS1_RFD_SH_LEFT_LITTLE	8
222 
223 #define	RNDX_BITS1_INDEX_BIG		((unsigned int) 0x0F)
224 #define	RNDX_BITS1_INDEX_SH_LEFT_BIG	16
225 #define	RNDX_BITS2_INDEX_SH_LEFT_BIG	8
226 #define	RNDX_BITS3_INDEX_SH_LEFT_BIG	0
227 
228 #define	RNDX_BITS1_INDEX_LITTLE		((unsigned int) 0xF0)
229 #define	RNDX_BITS1_INDEX_SH_LITTLE	4
230 #define	RNDX_BITS2_INDEX_SH_LEFT_LITTLE	4
231 #define	RNDX_BITS3_INDEX_SH_LEFT_LITTLE	12
232 
233 /* Auxiliary symbol information external record */
234 
235 union aux_ext {
236 	struct tir_ext	a_ti;
237 	struct rndx_ext	a_rndx;
238 	unsigned char	a_dnLow[4];
239 	unsigned char	a_dnHigh[4];
240 	unsigned char	a_isym[4];
241 	unsigned char	a_iss[4];
242 	unsigned char	a_width[4];
243 	unsigned char	a_count[4];
244 };
245 
246 #define AUX_GET_ANY(bigend, ax, field) \
247   ((bigend) ? bfd_getb32 ((ax)->field) : bfd_getl32 ((ax)->field))
248 
249 #define	AUX_GET_DNLOW(bigend, ax)	AUX_GET_ANY ((bigend), (ax), a_dnLow)
250 #define	AUX_GET_DNHIGH(bigend, ax)	AUX_GET_ANY ((bigend), (ax), a_dnHigh)
251 #define	AUX_GET_ISYM(bigend, ax)	AUX_GET_ANY ((bigend), (ax), a_isym)
252 #define AUX_GET_ISS(bigend, ax)		AUX_GET_ANY ((bigend), (ax), a_iss)
253 #define AUX_GET_WIDTH(bigend, ax)	AUX_GET_ANY ((bigend), (ax), a_width)
254 #define AUX_GET_COUNT(bigend, ax)	AUX_GET_ANY ((bigend), (ax), a_count)
255 
256 #define AUX_PUT_ANY(bigend, val, ax, field) \
257   ((bigend) \
258    ? (bfd_putb32 ((bfd_vma) (val), (ax)->field), 0) \
259    : (bfd_putl32 ((bfd_vma) (val), (ax)->field), 0))
260 
261 #define AUX_PUT_DNLOW(bigend, val, ax) \
262   AUX_PUT_ANY ((bigend), (val), (ax), a_dnLow)
263 #define AUX_PUT_DNHIGH(bigend, val, ax) \
264   AUX_PUT_ANY ((bigend), (val), (ax), a_dnHigh)
265 #define AUX_PUT_ISYM(bigend, val, ax) \
266   AUX_PUT_ANY ((bigend), (val), (ax), a_isym)
267 #define AUX_PUT_ISS(bigend, val, ax) \
268   AUX_PUT_ANY ((bigend), (val), (ax), a_iss)
269 #define AUX_PUT_WIDTH(bigend, val, ax) \
270   AUX_PUT_ANY ((bigend), (val), (ax), a_width)
271 #define AUX_PUT_COUNT(bigend, val, ax) \
272   AUX_PUT_ANY ((bigend), (val), (ax), a_count)
273 
274 /********************** SYMBOLS **********************/
275 
276 /* For efficiency, gdb deals directly with the unswapped symbolic
277    information (that way it only takes the time to swap information
278    that it really needs to read).  gdb originally retrieved the
279    information directly from the BFD backend information, but that
280    strategy, besides being sort of ugly, does not work for MIPS ELF,
281    which also uses ECOFF debugging information.  This structure holds
282    pointers to the (mostly) unswapped symbolic information.  */
283 
284 struct ecoff_debug_info
285 {
286   /* The swapped ECOFF symbolic header.  */
287   HDRR symbolic_header;
288 
289   /* Pointers to the unswapped symbolic information.  Note that the
290      pointers to external structures point to different sorts of
291      information on different ECOFF targets.  The ecoff_debug_swap
292      structure provides the sizes of the structures and the functions
293      needed to swap the information in and out.  These pointers are
294      all pointers to arrays, not single structures.  They will be NULL
295      if there are no instances of the relevant structure.  These
296      fields are also used by the assembler to output ECOFF debugging
297      information.  */
298   unsigned char *line;
299   void *external_dnr;	/* struct dnr_ext */
300   void *external_pdr;	/* struct pdr_ext */
301   void *external_sym;	/* struct sym_ext */
302   void *external_opt;	/* struct opt_ext */
303   union aux_ext *external_aux;
304   char *ss;
305   char *ssext;
306   void *external_fdr;	/* struct fdr_ext */
307   void *external_rfd;	/* struct rfd_ext */
308   void *external_ext;	/* struct ext_ext */
309 
310   /* These fields are used when linking.  They may disappear at some
311      point.  */
312   char *ssext_end;
313   void *external_ext_end;
314 
315   /* When linking, this field holds a mapping from the input FDR
316      numbers to the output numbers, and is used when writing out the
317      external symbols.  It is NULL if no mapping is required.  */
318   RFDT *ifdmap;
319 
320   /* The swapped FDR information.  Currently this is never NULL, but
321      code using this structure should probably double-check in case
322      this changes in the future.  This is a pointer to an array, not a
323      single structure.  */
324   FDR *fdr;
325 
326   /* When relaxing MIPS embedded PIC code, we may need to adjust
327      symbol values when they are output.  This is a linked list of
328      structures indicating how values should be adjusted.  There is no
329      requirement that the entries be in any order, or that they not
330      overlap.  This field is normally NULL, in which case no
331      adjustments need to be made.  */
332   struct ecoff_value_adjust *adjust;
333 };
334 
335 /* This structure describes how to adjust symbol values when
336    outputting MIPS embedded PIC code.  These adjustments only apply to
337    the internal symbols, as the external symbol values will come from
338    the hash table and have already been adjusted.  */
339 
340 struct ecoff_value_adjust
341 {
342   /* Next entry on adjustment list.  */
343   struct ecoff_value_adjust *next;
344   /* Starting VMA of adjustment.  This is the VMA in the ECOFF file,
345      not the offset from the start of the section.  Thus it should
346      indicate a particular section.  */
347   bfd_vma start;
348   /* Ending VMA of adjustment.  */
349   bfd_vma end;
350   /* Adjustment.  This should be added to the value of the symbol, or
351      FDR.  This is zero for the last entry in the array.  */
352   long adjust;
353 };
354 
355 /* These structures are used by the ECOFF find_nearest_line function.  */
356 
357 struct ecoff_fdrtab_entry
358 {
359   /* Base address in .text of this FDR.  */
360   bfd_vma base_addr;
361   FDR *fdr;
362 };
363 
364 struct ecoff_find_line
365 {
366   /* Allocated memory to hold function and file names.  */
367   char *find_buffer;
368 
369   /* FDR table, sorted by address: */
370   long fdrtab_len;
371   struct ecoff_fdrtab_entry *fdrtab;
372 
373   /* Cache entry for most recently found line information.  The sect
374      field is NULL if this cache does not contain valid information.  */
375   struct
376     {
377       asection *sect;
378       bfd_vma start;
379       bfd_vma stop;
380       const char *filename;
381       const char *functionname;
382       unsigned int line_num;
383     } cache;
384 };
385 
386 /********************** SWAPPING **********************/
387 
388 /* The generic ECOFF code needs to be able to swap debugging
389    information in and out in the specific format used by a particular
390    ECOFF implementation.  This structure provides the information
391    needed to do this.  */
392 
393 struct ecoff_debug_swap
394 {
395   /* Symbol table magic number.  */
396   int sym_magic;
397   /* Alignment of debugging information.  E.g., 4.  */
398   bfd_size_type debug_align;
399   /* Sizes of external symbolic information.  */
400   bfd_size_type external_hdr_size;
401   bfd_size_type external_dnr_size;
402   bfd_size_type external_pdr_size;
403   bfd_size_type external_sym_size;
404   bfd_size_type external_opt_size;
405   bfd_size_type external_fdr_size;
406   bfd_size_type external_rfd_size;
407   bfd_size_type external_ext_size;
408   /* Functions to swap in external symbolic data.  */
409   void (*swap_hdr_in) (bfd *, void *, HDRR *);
410   void (*swap_dnr_in) (bfd *, void *, DNR *);
411   void (*swap_pdr_in) (bfd *, void *, PDR *);
412   void (*swap_sym_in) (bfd *, void *, SYMR *);
413   void (*swap_opt_in) (bfd *, void *, OPTR *);
414   void (*swap_fdr_in) (bfd *, void *, FDR *);
415   void (*swap_rfd_in) (bfd *, void *, RFDT *);
416   void (*swap_ext_in) (bfd *, void *, EXTR *);
417   void (*swap_tir_in) (int, const struct tir_ext *, TIR *);
418   void (*swap_rndx_in) (int, const struct rndx_ext *, RNDXR *);
419   /* Functions to swap out external symbolic data.  */
420   void (*swap_hdr_out) (bfd *, const HDRR *, void *);
421   void (*swap_dnr_out) (bfd *, const DNR *, void *);
422   void (*swap_pdr_out) (bfd *, const PDR *, void *);
423   void (*swap_sym_out) (bfd *, const SYMR *, void *);
424   void (*swap_opt_out) (bfd *, const OPTR *, void *);
425   void (*swap_fdr_out) (bfd *, const FDR *, void *);
426   void (*swap_rfd_out) (bfd *, const RFDT *, void *);
427   void (*swap_ext_out) (bfd *, const EXTR *, void *);
428   void (*swap_tir_out) (int, const TIR *, struct tir_ext *);
429   void (*swap_rndx_out) (int, const RNDXR *, struct rndx_ext *);
430   /* Function to read symbol data and set up pointers in
431      ecoff_debug_info structure.  The section argument is used for
432      ELF, not straight ECOFF.  */
433   bfd_boolean (*read_debug_info) (bfd *, asection *, struct ecoff_debug_info *);
434 };
435 
436 #endif /* ! defined (ECOFF_H) */
437