1 /* Generic ECOFF support.
2    This does not include symbol information, found in sym.h and
3    symconst.h.
4 
5    Copyright (C) 2001-2020 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 3 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., 51 Franklin Street - Fifth Floor, Boston,
20    MA 02110-1301, USA.  */
21 
22 #ifndef ECOFF_H
23 #define ECOFF_H
24 
25 #include "coff/sym.h"
26 
27 /* Mips magic numbers used in filehdr.  MIPS_MAGIC_LITTLE is used on
28    little endian machines.  MIPS_MAGIC_BIG is used on big endian
29    machines.  Where is MIPS_MAGIC_1 from?  */
30 #define MIPS_MAGIC_1 0x0180
31 #define MIPS_MAGIC_LITTLE 0x0162
32 #define MIPS_MAGIC_BIG 0x0160
33 
34 /* These are the magic numbers used for MIPS code compiled at ISA
35    level 2.  */
36 #define MIPS_MAGIC_LITTLE2 0x0166
37 #define MIPS_MAGIC_BIG2 0x0163
38 
39 /* These are the magic numbers used for MIPS code compiled at ISA
40    level 3.  */
41 #define MIPS_MAGIC_LITTLE3 0x142
42 #define MIPS_MAGIC_BIG3 0x140
43 
44 /* Alpha magic numbers used in filehdr.  */
45 #define ALPHA_MAGIC 0x183
46 #define ALPHA_MAGIC_BSD 0x185
47 /* A compressed version of an ALPHA_MAGIC file created by DEC's tools.  */
48 #define ALPHA_MAGIC_COMPRESSED 0x188
49 
50 /* Magic numbers used in a.out header.  */
51 #define ECOFF_AOUT_OMAGIC 0407	/* not demand paged (ld -N).  */
52 #define ECOFF_AOUT_ZMAGIC 0413	/* demand load format, eg normal ld output */
53 
54 /* Names of special sections.  */
55 #define _TEXT   ".text"
56 #define _DATA   ".data"
57 #define _BSS    ".bss"
58 #define _RDATA	".rdata"
59 #define _SDATA	".sdata"
60 #define _SBSS	".sbss"
61 #define _LITA	".lita"
62 #define _LIT4	".lit4"
63 #define _LIT8	".lit8"
64 #define _LIB	".lib"
65 #define _INIT	".init"
66 #define _FINI	".fini"
67 #define _PDATA	".pdata"
68 #define _XDATA	".xdata"
69 #define _GOT	".got"
70 #define _HASH	".hash"
71 #define _DYNSYM	".dynsym"
72 #define _DYNSTR	".dynstr"
73 #define _RELDYN	".rel.dyn"
74 #define _CONFLIC ".conflic"
75 #define _COMMENT ".comment"
76 #define _LIBLIST ".liblist"
77 #define _DYNAMIC ".dynamic"
78 #define _RCONST	".rconst"
79 
80 /* ECOFF uses some additional section flags.  */
81 #define STYP_RDATA	     0x100
82 #define STYP_SDATA	     0x200
83 #define STYP_SBSS	     0x400
84 #define STYP_GOT	    0x1000
85 #define STYP_DYNAMIC	    0x2000
86 #define STYP_DYNSYM	    0x4000
87 #define STYP_RELDYN	    0x8000
88 #define STYP_DYNSTR	   0x10000
89 #define STYP_HASH	   0x20000
90 #define STYP_LIBLIST	   0x40000
91 #define STYP_CONFLIC	  0x100000
92 #define STYP_ECOFF_FINI	 0x1000000
93 #define STYP_EXTENDESC	 0x2000000 /* 0x02FFF000 bits => scn type, rest clr */
94 #define STYP_LITA	 0x4000000
95 #define STYP_LIT8	 0x8000000
96 #define STYP_LIT4	0x10000000
97 #define STYP_ECOFF_LIB	0x40000000
98 #define STYP_ECOFF_INIT 0x80000000
99 #define STYP_OTHER_LOAD (STYP_ECOFF_INIT | STYP_ECOFF_FINI)
100 
101 /* extended section types */
102 #define STYP_COMMENT	 0x2100000
103 #define STYP_RCONST	 0x2200000
104 #define STYP_XDATA	 0x2400000
105 #define STYP_PDATA	 0x2800000
106 
107 /* The linker needs a section to hold small common variables while
108    linking.  There is no convenient way to create it when the linker
109    needs it, so we always create one for each BFD.  We then avoid
110    writing it out.  */
111 #define SCOMMON ".scommon"
112 
113 /* If the extern bit in a reloc is 1, then r_symndx is an index into
114    the external symbol table.  If the extern bit is 0, then r_symndx
115    indicates a section, and is one of the following values.  */
116 #define RELOC_SECTION_NONE	0
117 #define RELOC_SECTION_TEXT	1
118 #define RELOC_SECTION_RDATA	2
119 #define RELOC_SECTION_DATA	3
120 #define RELOC_SECTION_SDATA	4
121 #define RELOC_SECTION_SBSS	5
122 #define RELOC_SECTION_BSS	6
123 #define RELOC_SECTION_INIT	7
124 #define RELOC_SECTION_LIT8	8
125 #define RELOC_SECTION_LIT4	9
126 #define RELOC_SECTION_XDATA    10
127 #define RELOC_SECTION_PDATA    11
128 #define RELOC_SECTION_FINI     12
129 #define RELOC_SECTION_LITA     13
130 #define RELOC_SECTION_ABS      14
131 #define RELOC_SECTION_RCONST   15
132 
133 #define NUM_RELOC_SECTIONS     16
134 
135 /********************** STABS **********************/
136 
137 /* gcc uses mips-tfile to output type information in special stabs
138    entries.  These must match the corresponding definition in
139    gcc/config/mips.h.  At some point, these should probably go into a
140    shared include file, but currently gcc and gdb do not share any
141    directories. */
142 #define CODE_MASK 0x8F300
143 #define ECOFF_IS_STAB(sym) (((sym)->index & 0xFFF00) == CODE_MASK)
144 #define ECOFF_MARK_STAB(code) ((code)+CODE_MASK)
145 #define ECOFF_UNMARK_STAB(code) ((code)-CODE_MASK)
146 #define STABS_SYMBOL "@stabs"
147 
148 /********************** COFF **********************/
149 
150 /* gcc also uses mips-tfile to output COFF debugging information.
151    These are the values it uses when outputting the .type directive.
152    These should also be in a shared include file.  */
153 #define N_BTMASK	(017)
154 #define N_TMASK		(060)
155 #define N_BTSHFT	(4)
156 #define N_TSHIFT	(2)
157 
158 /********************** AUX **********************/
159 
160 /* The auxiliary type information is the same on all known ECOFF
161    targets.  I can't see any reason that it would ever change, so I am
162    going to gamble and define the external structures here, in the
163    target independent ECOFF header file.  The internal forms are
164    defined in coff/sym.h, which was originally donated by MIPS
165    Computer Systems.  */
166 
167 /* Type information external record */
168 
169 struct tir_ext {
170 	unsigned char	t_bits1[1];
171 	unsigned char	t_tq45[1];
172 	unsigned char	t_tq01[1];
173 	unsigned char	t_tq23[1];
174 };
175 
176 #define	TIR_BITS1_FBITFIELD_BIG		((unsigned int) 0x80)
177 #define	TIR_BITS1_FBITFIELD_LITTLE	((unsigned int) 0x01)
178 
179 #define	TIR_BITS1_CONTINUED_BIG		((unsigned int) 0x40)
180 #define	TIR_BITS1_CONTINUED_LITTLE	((unsigned int) 0x02)
181 
182 #define	TIR_BITS1_BT_BIG		((unsigned int) 0x3F)
183 #define	TIR_BITS1_BT_SH_BIG		0
184 #define	TIR_BITS1_BT_LITTLE		((unsigned int) 0xFC)
185 #define	TIR_BITS1_BT_SH_LITTLE		2
186 
187 #define	TIR_BITS_TQ4_BIG		((unsigned int) 0xF0)
188 #define	TIR_BITS_TQ4_SH_BIG		4
189 #define	TIR_BITS_TQ5_BIG		((unsigned int) 0x0F)
190 #define	TIR_BITS_TQ5_SH_BIG		0
191 #define	TIR_BITS_TQ4_LITTLE		((unsigned int) 0x0F)
192 #define	TIR_BITS_TQ4_SH_LITTLE		0
193 #define	TIR_BITS_TQ5_LITTLE		((unsigned int) 0xF0)
194 #define	TIR_BITS_TQ5_SH_LITTLE		4
195 
196 #define	TIR_BITS_TQ0_BIG		((unsigned int) 0xF0)
197 #define	TIR_BITS_TQ0_SH_BIG		4
198 #define	TIR_BITS_TQ1_BIG		((unsigned int) 0x0F)
199 #define	TIR_BITS_TQ1_SH_BIG		0
200 #define	TIR_BITS_TQ0_LITTLE		((unsigned int) 0x0F)
201 #define	TIR_BITS_TQ0_SH_LITTLE		0
202 #define	TIR_BITS_TQ1_LITTLE		((unsigned int) 0xF0)
203 #define	TIR_BITS_TQ1_SH_LITTLE		4
204 
205 #define	TIR_BITS_TQ2_BIG		((unsigned int) 0xF0)
206 #define	TIR_BITS_TQ2_SH_BIG		4
207 #define	TIR_BITS_TQ3_BIG		((unsigned int) 0x0F)
208 #define	TIR_BITS_TQ3_SH_BIG		0
209 #define	TIR_BITS_TQ2_LITTLE		((unsigned int) 0x0F)
210 #define	TIR_BITS_TQ2_SH_LITTLE		0
211 #define	TIR_BITS_TQ3_LITTLE		((unsigned int) 0xF0)
212 #define	TIR_BITS_TQ3_SH_LITTLE		4
213 
214 /* Relative symbol external record */
215 
216 struct rndx_ext {
217 	unsigned char	r_bits[4];
218 };
219 
220 #define	RNDX_BITS0_RFD_SH_LEFT_BIG	4
221 #define	RNDX_BITS1_RFD_BIG		((unsigned int) 0xF0)
222 #define	RNDX_BITS1_RFD_SH_BIG		4
223 
224 #define	RNDX_BITS0_RFD_SH_LEFT_LITTLE	0
225 #define	RNDX_BITS1_RFD_LITTLE		((unsigned int) 0x0F)
226 #define	RNDX_BITS1_RFD_SH_LEFT_LITTLE	8
227 
228 #define	RNDX_BITS1_INDEX_BIG		((unsigned int) 0x0F)
229 #define	RNDX_BITS1_INDEX_SH_LEFT_BIG	16
230 #define	RNDX_BITS2_INDEX_SH_LEFT_BIG	8
231 #define	RNDX_BITS3_INDEX_SH_LEFT_BIG	0
232 
233 #define	RNDX_BITS1_INDEX_LITTLE		((unsigned int) 0xF0)
234 #define	RNDX_BITS1_INDEX_SH_LITTLE	4
235 #define	RNDX_BITS2_INDEX_SH_LEFT_LITTLE	4
236 #define	RNDX_BITS3_INDEX_SH_LEFT_LITTLE	12
237 
238 /* Auxiliary symbol information external record */
239 
240 union aux_ext {
241 	struct tir_ext	a_ti;
242 	struct rndx_ext	a_rndx;
243 	unsigned char	a_dnLow[4];
244 	unsigned char	a_dnHigh[4];
245 	unsigned char	a_isym[4];
246 	unsigned char	a_iss[4];
247 	unsigned char	a_width[4];
248 	unsigned char	a_count[4];
249 };
250 
251 #define AUX_GET_ANY(bigend, ax, field) \
252   ((bigend) ? bfd_getb32 ((ax)->field) : bfd_getl32 ((ax)->field))
253 
254 #define	AUX_GET_DNLOW(bigend, ax)	AUX_GET_ANY ((bigend), (ax), a_dnLow)
255 #define	AUX_GET_DNHIGH(bigend, ax)	AUX_GET_ANY ((bigend), (ax), a_dnHigh)
256 #define	AUX_GET_ISYM(bigend, ax)	AUX_GET_ANY ((bigend), (ax), a_isym)
257 #define AUX_GET_ISS(bigend, ax)		AUX_GET_ANY ((bigend), (ax), a_iss)
258 #define AUX_GET_WIDTH(bigend, ax)	AUX_GET_ANY ((bigend), (ax), a_width)
259 #define AUX_GET_COUNT(bigend, ax)	AUX_GET_ANY ((bigend), (ax), a_count)
260 
261 #define AUX_PUT_ANY(bigend, val, ax, field) \
262   ((bigend) \
263    ? (bfd_putb32 ((bfd_vma) (val), (ax)->field), 0) \
264    : (bfd_putl32 ((bfd_vma) (val), (ax)->field), 0))
265 
266 #define AUX_PUT_DNLOW(bigend, val, ax) \
267   AUX_PUT_ANY ((bigend), (val), (ax), a_dnLow)
268 #define AUX_PUT_DNHIGH(bigend, val, ax) \
269   AUX_PUT_ANY ((bigend), (val), (ax), a_dnHigh)
270 #define AUX_PUT_ISYM(bigend, val, ax) \
271   AUX_PUT_ANY ((bigend), (val), (ax), a_isym)
272 #define AUX_PUT_ISS(bigend, val, ax) \
273   AUX_PUT_ANY ((bigend), (val), (ax), a_iss)
274 #define AUX_PUT_WIDTH(bigend, val, ax) \
275   AUX_PUT_ANY ((bigend), (val), (ax), a_width)
276 #define AUX_PUT_COUNT(bigend, val, ax) \
277   AUX_PUT_ANY ((bigend), (val), (ax), a_count)
278 
279 /********************** SYMBOLS **********************/
280 
281 /* For efficiency, gdb deals directly with the unswapped symbolic
282    information (that way it only takes the time to swap information
283    that it really needs to read).  gdb originally retrieved the
284    information directly from the BFD backend information, but that
285    strategy, besides being sort of ugly, does not work for MIPS ELF,
286    which also uses ECOFF debugging information.  This structure holds
287    pointers to the (mostly) unswapped symbolic information.  */
288 
289 struct ecoff_debug_info
290 {
291   /* The swapped ECOFF symbolic header.  */
292   HDRR symbolic_header;
293 
294   /* Pointers to the unswapped symbolic information.  Note that the
295      pointers to external structures point to different sorts of
296      information on different ECOFF targets.  The ecoff_debug_swap
297      structure provides the sizes of the structures and the functions
298      needed to swap the information in and out.  These pointers are
299      all pointers to arrays, not single structures.  They will be NULL
300      if there are no instances of the relevant structure.  These
301      fields are also used by the assembler to output ECOFF debugging
302      information.  */
303   unsigned char *line;
304   void *external_dnr;	/* struct dnr_ext */
305   void *external_pdr;	/* struct pdr_ext */
306   void *external_sym;	/* struct sym_ext */
307   void *external_opt;	/* struct opt_ext */
308   union aux_ext *external_aux;
309   char *ss;
310   char *ssext;
311   void *external_fdr;	/* struct fdr_ext */
312   void *external_rfd;	/* struct rfd_ext */
313   void *external_ext;	/* struct ext_ext */
314 
315   /* These fields are used when linking.  They may disappear at some
316      point.  */
317   char *ssext_end;
318   void *external_ext_end;
319 
320   /* When linking, this field holds a mapping from the input FDR
321      numbers to the output numbers, and is used when writing out the
322      external symbols.  It is NULL if no mapping is required.  */
323   RFDT *ifdmap;
324 
325   /* The swapped FDR information.  Currently this is never NULL, but
326      code using this structure should probably double-check in case
327      this changes in the future.  This is a pointer to an array, not a
328      single structure.  */
329   FDR *fdr;
330 };
331 
332 /* These structures are used by the ECOFF find_nearest_line function.  */
333 
334 struct ecoff_fdrtab_entry
335 {
336   /* Base address in .text of this FDR.  */
337   bfd_vma base_addr;
338   FDR *fdr;
339 };
340 
341 struct ecoff_find_line
342 {
343   /* Allocated memory to hold function and file names.  */
344   char *find_buffer;
345 
346   /* FDR table, sorted by address: */
347   long fdrtab_len;
348   struct ecoff_fdrtab_entry *fdrtab;
349 
350   /* Cache entry for most recently found line information.  The sect
351      field is NULL if this cache does not contain valid information.  */
352   struct
353     {
354       asection *sect;
355       bfd_vma start;
356       bfd_vma stop;
357       const char *filename;
358       const char *functionname;
359       unsigned int line_num;
360     } cache;
361 };
362 
363 /********************** SWAPPING **********************/
364 
365 /* The generic ECOFF code needs to be able to swap debugging
366    information in and out in the specific format used by a particular
367    ECOFF implementation.  This structure provides the information
368    needed to do this.  */
369 
370 struct ecoff_debug_swap
371 {
372   /* Symbol table magic number.  */
373   int sym_magic;
374   /* Alignment of debugging information.  E.g., 4.  */
375   bfd_size_type debug_align;
376   /* Sizes of external symbolic information.  */
377   bfd_size_type external_hdr_size;
378   bfd_size_type external_dnr_size;
379   bfd_size_type external_pdr_size;
380   bfd_size_type external_sym_size;
381   bfd_size_type external_opt_size;
382   bfd_size_type external_fdr_size;
383   bfd_size_type external_rfd_size;
384   bfd_size_type external_ext_size;
385   /* Functions to swap in external symbolic data.  */
386   void (*swap_hdr_in) (bfd *, void *, HDRR *);
387   void (*swap_dnr_in) (bfd *, void *, DNR *);
388   void (*swap_pdr_in) (bfd *, void *, PDR *);
389   void (*swap_sym_in) (bfd *, void *, SYMR *);
390   void (*swap_opt_in) (bfd *, void *, OPTR *);
391   void (*swap_fdr_in) (bfd *, void *, FDR *);
392   void (*swap_rfd_in) (bfd *, void *, RFDT *);
393   void (*swap_ext_in) (bfd *, void *, EXTR *);
394   void (*swap_tir_in) (int, const struct tir_ext *, TIR *);
395   void (*swap_rndx_in) (int, const struct rndx_ext *, RNDXR *);
396   /* Functions to swap out external symbolic data.  */
397   void (*swap_hdr_out) (bfd *, const HDRR *, void *);
398   void (*swap_dnr_out) (bfd *, const DNR *, void *);
399   void (*swap_pdr_out) (bfd *, const PDR *, void *);
400   void (*swap_sym_out) (bfd *, const SYMR *, void *);
401   void (*swap_opt_out) (bfd *, const OPTR *, void *);
402   void (*swap_fdr_out) (bfd *, const FDR *, void *);
403   void (*swap_rfd_out) (bfd *, const RFDT *, void *);
404   void (*swap_ext_out) (bfd *, const EXTR *, void *);
405   void (*swap_tir_out) (int, const TIR *, struct tir_ext *);
406   void (*swap_rndx_out) (int, const RNDXR *, struct rndx_ext *);
407   /* Function to read symbol data and set up pointers in
408      ecoff_debug_info structure.  The section argument is used for
409      ELF, not straight ECOFF.  */
410   bfd_boolean (*read_debug_info) (bfd *, asection *, struct ecoff_debug_info *);
411 };
412 
413 #endif /* ! defined (ECOFF_H) */
414