1 /* ARM ELF support for BFD.
2    Copyright (C) 1998-2016 Free Software Foundation, Inc.
3 
4    This file is part of BFD, the Binary File Descriptor library.
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 3 of the License, or
9    (at your option) any later version.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program; if not, write to the Free Software Foundation,
18    Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
19 
20 #ifndef _ELF_ARM_H
21 #define _ELF_ARM_H
22 
23 #include "elf/reloc-macros.h"
24 
25 /* Processor specific flags for the ELF header e_flags field.  */
26 #define EF_ARM_RELEXEC     0x01
27 #define EF_ARM_INTERWORK   0x04
28 #define EF_ARM_APCS_26     0x08
29 #define EF_ARM_APCS_FLOAT  0x10
30 #define EF_ARM_PIC         0x20
31 #define EF_ARM_ALIGN8	   0x40		/* 8-bit structure alignment is in use.  */
32 #define EF_ARM_NEW_ABI     0x80
33 #define EF_ARM_OLD_ABI     0x100
34 #define EF_ARM_SOFT_FLOAT  0x200
35 #define EF_ARM_VFP_FLOAT   0x400
36 #define EF_ARM_MAVERICK_FLOAT 0x800
37 
38 /* Frame unwind information */
39 #define PT_ARM_EXIDX (PT_LOPROC + 1)
40 
41 /* Other constants defined in the ARM ELF spec. version B-01.  */
42 #define EF_ARM_SYMSARESORTED 0x04	/* NB conflicts with EF_INTERWORK.  */
43 #define EF_ARM_DYNSYMSUSESEGIDX 0x08	/* NB conflicts with EF_APCS26.  */
44 #define EF_ARM_MAPSYMSFIRST 0x10	/* NB conflicts with EF_APCS_FLOAT.  */
45 #define EF_ARM_EABIMASK      0xFF000000
46 
47 /* New constants defined in the ARM ELF spec. version XXX.
48    Only valid in conjunction with EF_ARM_EABI_VER5. */
49 #define EF_ARM_ABI_FLOAT_SOFT 0x200	/* NB conflicts with EF_ARM_SOFT_FLOAT.  */
50 #define EF_ARM_ABI_FLOAT_HARD 0x400	/* NB conflicts with EF_ARM_VFP_FLOAT.  */
51 
52 /* Constants defined in AAELF.  */
53 #define EF_ARM_BE8	    0x00800000
54 #define EF_ARM_LE8	    0x00400000
55 
56 #define EF_ARM_EABI_VERSION(flags) ((flags) & EF_ARM_EABIMASK)
57 #define EF_ARM_EABI_UNKNOWN  0x00000000
58 #define EF_ARM_EABI_VER1     0x01000000
59 #define EF_ARM_EABI_VER2     0x02000000
60 #define EF_ARM_EABI_VER3     0x03000000
61 #define EF_ARM_EABI_VER4     0x04000000
62 #define EF_ARM_EABI_VER5     0x05000000
63 
64 /* Local aliases for some flags to match names used by COFF port.  */
65 #define F_INTERWORK	   EF_ARM_INTERWORK
66 #define F_APCS26	   EF_ARM_APCS_26
67 #define F_APCS_FLOAT	   EF_ARM_APCS_FLOAT
68 #define F_PIC              EF_ARM_PIC
69 #define F_SOFT_FLOAT	   EF_ARM_SOFT_FLOAT
70 #define F_VFP_FLOAT	   EF_ARM_VFP_FLOAT
71 
72 /* Additional symbol types for Thumb.  */
73 #define STT_ARM_TFUNC      STT_LOPROC   /* A Thumb function.  */
74 #define STT_ARM_16BIT      STT_HIPROC   /* A Thumb label.  */
75 
76 /* Additional section types.  */
77 #define SHT_ARM_EXIDX	       0x70000001	/* Section holds ARM unwind info.  */
78 #define SHT_ARM_PREEMPTMAP     0x70000002	/* Section pre-emption details.  */
79 #define SHT_ARM_ATTRIBUTES     0x70000003	/* Section holds attributes.  */
80 #define SHT_ARM_DEBUGOVERLAY   0x70000004	/* Section holds overlay debug info.  */
81 #define SHT_ARM_OVERLAYSECTION 0x70000005	/* Section holds GDB and overlay integration info.  */
82 
83 /* ARM-specific values for sh_flags.  */
84 #define SHF_ENTRYSECT      0x10000000   /* Section contains an entry point.  */
85 #define SHF_ARM_NOREAD     0x20000000   /* Section contains code that can be place on no read memory area.  */
86 #define SHF_COMDEF         0x80000000   /* Section may be multiply defined in the input to a link step.  */
87 
88 /* ARM-specific program header flags.  */
89 #define PF_ARM_SB          0x10000000   /* Segment contains the location addressed by the static base.  */
90 #define PF_ARM_PI          0x20000000   /* Segment is position-independent.  */
91 #define PF_ARM_ABS         0x40000000   /* Segment must be loaded at its base address.  */
92 
93 /* Values for the Tag_CPU_arch EABI attribute.  */
94 #define TAG_CPU_ARCH_PRE_V4	0
95 #define TAG_CPU_ARCH_V4		1
96 #define TAG_CPU_ARCH_V4T	2
97 #define TAG_CPU_ARCH_V5T	3
98 #define TAG_CPU_ARCH_V5TE	4
99 #define TAG_CPU_ARCH_V5TEJ	5
100 #define TAG_CPU_ARCH_V6		6
101 #define TAG_CPU_ARCH_V6KZ	7
102 #define TAG_CPU_ARCH_V6T2	8
103 #define TAG_CPU_ARCH_V6K	9
104 #define TAG_CPU_ARCH_V7		10
105 #define TAG_CPU_ARCH_V6_M	11
106 #define TAG_CPU_ARCH_V6S_M	12
107 #define TAG_CPU_ARCH_V7E_M	13
108 #define TAG_CPU_ARCH_V8		14
109 #define TAG_CPU_ARCH_V8M_BASE	16
110 #define TAG_CPU_ARCH_V8M_MAIN	17
111 #define MAX_TAG_CPU_ARCH	TAG_CPU_ARCH_V8M_MAIN
112 /* Pseudo-architecture to allow objects to be compatible with the subset of
113    armv4t and armv6-m.  This value should never be stored in object files.  */
114 #define TAG_CPU_ARCH_V4T_PLUS_V6_M (MAX_TAG_CPU_ARCH + 1)
115 
116 /* Relocation types.  */
117 
118 START_RELOC_NUMBERS (elf_arm_reloc_type)
119 /* AAELF official names and numbers.  */
120   RELOC_NUMBER (R_ARM_NONE,            	  0)
121   RELOC_NUMBER (R_ARM_PC24,            	  1)   /* deprecated */
122   RELOC_NUMBER (R_ARM_ABS32,           	  2)
123   RELOC_NUMBER (R_ARM_REL32,           	  3)
124   RELOC_NUMBER (R_ARM_LDR_PC_G0,       	  4)
125   RELOC_NUMBER (R_ARM_ABS16,           	  5)
126   RELOC_NUMBER (R_ARM_ABS12,           	  6)
127   RELOC_NUMBER (R_ARM_THM_ABS5,        	  7)
128   RELOC_NUMBER (R_ARM_ABS8,            	  8)
129   RELOC_NUMBER (R_ARM_SBREL32,         	  9)
130   RELOC_NUMBER (R_ARM_THM_CALL,        	 10)
131   RELOC_NUMBER (R_ARM_THM_PC8,         	 11)
132   RELOC_NUMBER (R_ARM_BREL_ADJ,	       	 12)
133   RELOC_NUMBER (R_ARM_TLS_DESC,          13)
134   RELOC_NUMBER (R_ARM_THM_SWI8,        	 14)   /* obsolete */
135   RELOC_NUMBER (R_ARM_XPC25,           	 15)   /* obsolete */
136   RELOC_NUMBER (R_ARM_THM_XPC22,       	 16)   /* obsolete */
137   RELOC_NUMBER (R_ARM_TLS_DTPMOD32,    	 17)
138   RELOC_NUMBER (R_ARM_TLS_DTPOFF32,    	 18)
139   RELOC_NUMBER (R_ARM_TLS_TPOFF32,     	 19)
140   RELOC_NUMBER (R_ARM_COPY,            	 20)   /* Copy symbol at runtime.  */
141   RELOC_NUMBER (R_ARM_GLOB_DAT,        	 21)   /* Create GOT entry.  */
142   RELOC_NUMBER (R_ARM_JUMP_SLOT,       	 22)   /* Create PLT entry.  */
143   RELOC_NUMBER (R_ARM_RELATIVE,        	 23)   /* Adjust by program base.  */
144   RELOC_NUMBER (R_ARM_GOTOFF32,        	 24)   /* 32 bit offset to GOT.  */
145   RELOC_NUMBER (R_ARM_BASE_PREL,       	 25)   /* 32 bit PC relative offset to GOT.  */
146   RELOC_NUMBER (R_ARM_GOT_BREL,        	 26)   /* 32 bit GOT entry.  */
147   RELOC_NUMBER (R_ARM_PLT32,           	 27)   /* deprecated - 32 bit PLT address.  */
148   RELOC_NUMBER (R_ARM_CALL,            	 28)
149   RELOC_NUMBER (R_ARM_JUMP24,          	 29)
150   RELOC_NUMBER (R_ARM_THM_JUMP24,      	 30)
151   RELOC_NUMBER (R_ARM_BASE_ABS,        	 31)
152   RELOC_NUMBER (R_ARM_ALU_PCREL7_0,    	 32)   /* obsolete */
153   RELOC_NUMBER (R_ARM_ALU_PCREL15_8,   	 33)   /* obsolete */
154   RELOC_NUMBER (R_ARM_ALU_PCREL23_15,  	 34)   /* obsolete */
155   RELOC_NUMBER (R_ARM_LDR_SBREL_11_0,  	 35)   /* deprecated, should have _NC suffix */
156   RELOC_NUMBER (R_ARM_ALU_SBREL_19_12, 	 36)   /* deprecated, should have _NC suffix */
157   RELOC_NUMBER (R_ARM_ALU_SBREL_27_20, 	 37)   /* deprecated, should have _CK suffix */
158   RELOC_NUMBER (R_ARM_TARGET1,         	 38)
159   RELOC_NUMBER (R_ARM_SBREL31,         	 39)   /* deprecated */
160   RELOC_NUMBER (R_ARM_V4BX,            	 40)
161   RELOC_NUMBER (R_ARM_TARGET2,	       	 41)
162   RELOC_NUMBER (R_ARM_PREL31,	       	 42)
163   RELOC_NUMBER (R_ARM_MOVW_ABS_NC,     	 43)
164   RELOC_NUMBER (R_ARM_MOVT_ABS,        	 44)
165   RELOC_NUMBER (R_ARM_MOVW_PREL_NC,    	 45)
166   RELOC_NUMBER (R_ARM_MOVT_PREL,       	 46)
167   RELOC_NUMBER (R_ARM_THM_MOVW_ABS_NC, 	 47)
168   RELOC_NUMBER (R_ARM_THM_MOVT_ABS,    	 48)
169   RELOC_NUMBER (R_ARM_THM_MOVW_PREL_NC,	 49)
170   RELOC_NUMBER (R_ARM_THM_MOVT_PREL,   	 50)
171   RELOC_NUMBER (R_ARM_THM_JUMP19,      	 51)
172   RELOC_NUMBER (R_ARM_THM_JUMP6,       	 52)
173   RELOC_NUMBER (R_ARM_THM_ALU_PREL_11_0, 53)
174   RELOC_NUMBER (R_ARM_THM_PC12,        	 54)
175   RELOC_NUMBER (R_ARM_ABS32_NOI,       	 55)
176   RELOC_NUMBER (R_ARM_REL32_NOI,       	 56)
177   RELOC_NUMBER (R_ARM_ALU_PC_G0_NC,      57)
178   RELOC_NUMBER (R_ARM_ALU_PC_G0,         58)
179   RELOC_NUMBER (R_ARM_ALU_PC_G1_NC,      59)
180   RELOC_NUMBER (R_ARM_ALU_PC_G1,         60)
181   RELOC_NUMBER (R_ARM_ALU_PC_G2,         61)
182   RELOC_NUMBER (R_ARM_LDR_PC_G1,         62)
183   RELOC_NUMBER (R_ARM_LDR_PC_G2,         63)
184   RELOC_NUMBER (R_ARM_LDRS_PC_G0,        64)
185   RELOC_NUMBER (R_ARM_LDRS_PC_G1,        65)
186   RELOC_NUMBER (R_ARM_LDRS_PC_G2,        66)
187   RELOC_NUMBER (R_ARM_LDC_PC_G0,         67)
188   RELOC_NUMBER (R_ARM_LDC_PC_G1,         68)
189   RELOC_NUMBER (R_ARM_LDC_PC_G2,         69)
190   RELOC_NUMBER (R_ARM_ALU_SB_G0_NC,      70)
191   RELOC_NUMBER (R_ARM_ALU_SB_G0,         71)
192   RELOC_NUMBER (R_ARM_ALU_SB_G1_NC,      72)
193   RELOC_NUMBER (R_ARM_ALU_SB_G1,         73)
194   RELOC_NUMBER (R_ARM_ALU_SB_G2,         74)
195   RELOC_NUMBER (R_ARM_LDR_SB_G0,         75)
196   RELOC_NUMBER (R_ARM_LDR_SB_G1,         76)
197   RELOC_NUMBER (R_ARM_LDR_SB_G2,         77)
198   RELOC_NUMBER (R_ARM_LDRS_SB_G0,        78)
199   RELOC_NUMBER (R_ARM_LDRS_SB_G1,        79)
200   RELOC_NUMBER (R_ARM_LDRS_SB_G2,        80)
201   RELOC_NUMBER (R_ARM_LDC_SB_G0,         81)
202   RELOC_NUMBER (R_ARM_LDC_SB_G1,         82)
203   RELOC_NUMBER (R_ARM_LDC_SB_G2,         83)
204   RELOC_NUMBER (R_ARM_MOVW_BREL_NC,    	 84)
205   RELOC_NUMBER (R_ARM_MOVT_BREL,       	 85)
206   RELOC_NUMBER (R_ARM_MOVW_BREL,       	 86)
207   RELOC_NUMBER (R_ARM_THM_MOVW_BREL_NC,	 87)
208   RELOC_NUMBER (R_ARM_THM_MOVT_BREL,   	 88)
209   RELOC_NUMBER (R_ARM_THM_MOVW_BREL,   	 89)
210   RELOC_NUMBER (R_ARM_TLS_GOTDESC,       90)
211   RELOC_NUMBER (R_ARM_TLS_CALL,          91)
212   RELOC_NUMBER (R_ARM_TLS_DESCSEQ,       92)
213   RELOC_NUMBER (R_ARM_THM_TLS_CALL,      93)
214   RELOC_NUMBER (R_ARM_PLT32_ABS,       	 94)
215   RELOC_NUMBER (R_ARM_GOT_ABS,	       	 95)
216   RELOC_NUMBER (R_ARM_GOT_PREL,	       	 96)
217   RELOC_NUMBER (R_ARM_GOT_BREL12,      	 97)
218   RELOC_NUMBER (R_ARM_GOTOFF12,	       	 98)
219   RELOC_NUMBER (R_ARM_GOTRELAX,	       	 99)
220   RELOC_NUMBER (R_ARM_GNU_VTENTRY,    	100)   /* deprecated - old C++ abi */
221   RELOC_NUMBER (R_ARM_GNU_VTINHERIT,  	101)   /* deprecated - old C++ abi */
222   RELOC_NUMBER (R_ARM_THM_JUMP11,     	102)
223   RELOC_NUMBER (R_ARM_THM_JUMP8,      	103)
224   RELOC_NUMBER (R_ARM_TLS_GD32,	      	104)
225   RELOC_NUMBER (R_ARM_TLS_LDM32,      	105)
226   RELOC_NUMBER (R_ARM_TLS_LDO32,      	106)
227   RELOC_NUMBER (R_ARM_TLS_IE32,       	107)
228   RELOC_NUMBER (R_ARM_TLS_LE32,	      	108)
229   RELOC_NUMBER (R_ARM_TLS_LDO12,      	109)
230   RELOC_NUMBER (R_ARM_TLS_LE12,	      	110)
231   RELOC_NUMBER (R_ARM_TLS_IE12GP,     	111)
232   /* 112 - 127 private range */
233   RELOC_NUMBER (R_ARM_ME_TOO,	        128)   /* obsolete */
234   RELOC_NUMBER (R_ARM_THM_TLS_DESCSEQ  ,129)
235 
236   RELOC_NUMBER (R_ARM_THM_ALU_ABS_G0_NC,132)
237   RELOC_NUMBER (R_ARM_THM_ALU_ABS_G1_NC,133)
238   RELOC_NUMBER (R_ARM_THM_ALU_ABS_G2_NC,134)
239   RELOC_NUMBER (R_ARM_THM_ALU_ABS_G3_NC,135)
240 
241   RELOC_NUMBER (R_ARM_IRELATIVE,      	160)
242 
243   /* Extensions?  R=read-only?  */
244   RELOC_NUMBER (R_ARM_RXPC25,         	249)
245   RELOC_NUMBER (R_ARM_RSBREL32,       	250)
246   RELOC_NUMBER (R_ARM_THM_RPC22,      	251)
247   RELOC_NUMBER (R_ARM_RREL32,         	252)
248   RELOC_NUMBER (R_ARM_RABS32,         	253)
249   RELOC_NUMBER (R_ARM_RPC24,          	254)
250   RELOC_NUMBER (R_ARM_RBASE,          	255)
251 
252   /* Unofficial names for some of the relocs.  */
253   FAKE_RELOC (R_ARM_GOTOFF,             R_ARM_GOTOFF32)   /* 32 bit offset to GOT.  */
254   FAKE_RELOC (R_ARM_THM_PC22,           R_ARM_THM_CALL)
255   FAKE_RELOC (R_ARM_THM_PC11,           R_ARM_THM_JUMP11)
256   FAKE_RELOC (R_ARM_THM_PC9,            R_ARM_THM_JUMP8)
257 
258   /* Relocs with both a different name, and (apparently) different meaning in
259      GNU usage.  */
260   FAKE_RELOC (R_ARM_GOTPC,              R_ARM_BASE_PREL)  /* 32 bit PC relative offset to GOT.  */
261   FAKE_RELOC (R_ARM_GOT32,              R_ARM_GOT_BREL)   /* 32 bit GOT entry.  */
262   FAKE_RELOC (R_ARM_ROSEGREL32,         R_ARM_SBREL31)    /* ??? */
263   FAKE_RELOC (R_ARM_AMP_VCALL9,         R_ARM_BREL_ADJ)   /* Thumb-something.  Not used.  */
264 
265 END_RELOC_NUMBERS (R_ARM_max = 256)
266 
267 #ifdef BFD_ARCH_SIZE
268 /* EABI object attributes.  */
269 
270 enum
271 {
272   /* 0-3 are generic.  */
273   Tag_CPU_raw_name = 4,
274   Tag_CPU_name,
275   Tag_CPU_arch,
276   Tag_CPU_arch_profile,
277   Tag_ARM_ISA_use,
278   Tag_THUMB_ISA_use,
279   Tag_FP_arch,
280   Tag_WMMX_arch,
281   Tag_Advanced_SIMD_arch,
282   Tag_PCS_config,
283   Tag_ABI_PCS_R9_use,
284   Tag_ABI_PCS_RW_data,
285   Tag_ABI_PCS_RO_data,
286   Tag_ABI_PCS_GOT_use,
287   Tag_ABI_PCS_wchar_t,
288   Tag_ABI_FP_rounding,
289   Tag_ABI_FP_denormal,
290   Tag_ABI_FP_exceptions,
291   Tag_ABI_FP_user_exceptions,
292   Tag_ABI_FP_number_model,
293   Tag_ABI_align_needed,
294   Tag_ABI_align_preserved,
295   Tag_ABI_enum_size,
296   Tag_ABI_HardFP_use,
297   Tag_ABI_VFP_args,
298   Tag_ABI_WMMX_args,
299   Tag_ABI_optimization_goals,
300   Tag_ABI_FP_optimization_goals,
301   /* 32 is generic (Tag_compatibility).  */
302   Tag_undefined33 = 33,
303   Tag_CPU_unaligned_access,
304   Tag_undefined35,
305   Tag_FP_HP_extension,
306   Tag_undefined37,
307   Tag_ABI_FP_16bit_format,
308   Tag_undefined39,
309   Tag_undefined40,
310   Tag_undefined41,
311   Tag_MPextension_use,
312   Tag_undefined_43,
313   Tag_DIV_use,
314   Tag_DSP_extension = 46,
315   Tag_nodefaults = 64,
316   Tag_also_compatible_with,
317   Tag_T2EE_use,
318   Tag_conformance,
319   Tag_Virtualization_use,
320   Tag_undefined69,
321   Tag_MPextension_use_legacy,
322 
323   /* The following tags are legacy names for other tags.  */
324   Tag_VFP_arch = Tag_FP_arch,
325   Tag_ABI_align8_needed = Tag_ABI_align_needed,
326   Tag_ABI_align8_preserved = Tag_ABI_align_preserved,
327   Tag_VFP_HP_extension = Tag_FP_HP_extension
328 };
329 
330 /* Values for Tag_ABI_FP_number_model.  */
331 enum
332 {
333   AEABI_FP_number_model_none = 0,
334   AEABI_FP_number_model_ieee754_number = 1,
335   AEABI_FP_number_model_rtabi = 2,
336   AEABI_FP_number_model_ieee754_all = 3
337 };
338 
339 /* Values for Tag_ABI_VFP_args.  */
340 enum
341 {
342   AEABI_VFP_args_base = 0,
343   AEABI_VFP_args_vfp = 1,
344   AEABI_VFP_args_toolchain = 2,
345   AEABI_VFP_args_compatible = 3
346 };
347 #endif
348 
349 /* The name of the note section used to identify arm variants.  */
350 #define ARM_NOTE_SECTION ".note.gnu.arm.ident"
351 
352 /* Special section names.  */
353 #define ELF_STRING_ARM_unwind           ".ARM.exidx"
354 #define ELF_STRING_ARM_unwind_info      ".ARM.extab"
355 #define ELF_STRING_ARM_unwind_once      ".gnu.linkonce.armexidx."
356 #define ELF_STRING_ARM_unwind_info_once ".gnu.linkonce.armextab."
357 
358 enum arm_st_branch_type {
359   ST_BRANCH_TO_ARM,
360   ST_BRANCH_TO_THUMB,
361   ST_BRANCH_LONG,
362   ST_BRANCH_UNKNOWN,
363   ST_BRANCH_ENUM_SIZE
364 };
365 
366 #define NUM_ENUM_ARM_ST_BRANCH_TYPE_BITS 2
367 #define ENUM_ARM_ST_BRANCH_TYPE_BITMASK	\
368   ((1 << NUM_ENUM_ARM_ST_BRANCH_TYPE_BITS) - 1)
369 
370 #define ARM_GET_SYM_BRANCH_TYPE(STI) \
371   ((enum arm_st_branch_type) ((STI) & ENUM_ARM_ST_BRANCH_TYPE_BITMASK))
372 #ifdef BFD_ASSERT
373 #define ARM_SET_SYM_BRANCH_TYPE(STI, TYPE)			\
374   do {								\
375     BFD_ASSERT (TYPE <= ST_BRANCH_ENUM_SIZE);			\
376     BFD_ASSERT ((1 << NUM_ENUM_ARM_ST_BRANCH_TYPE_BITS)		\
377 		>= ST_BRANCH_ENUM_SIZE);			\
378     (STI) = (((STI) & ~ENUM_ARM_ST_BRANCH_TYPE_BITMASK)		\
379 	     | ((TYPE) & ENUM_ARM_ST_BRANCH_TYPE_BITMASK));	\
380   } while (0)
381 #else
382 #define ARM_SET_SYM_BRANCH_TYPE(STI, TYPE)			\
383   (STI) = (((STI) & ~ENUM_ARM_ST_BRANCH_TYPE_BITMASK)		\
384 	   | ((TYPE) & ENUM_ARM_ST_BRANCH_TYPE_BITMASK))
385 #endif
386 
387 #endif /* _ELF_ARM_H */
388