include/elf/xtensa.h

   1 /* Xtensa ELF support for BFD.
   2    Copyright (C) 2003-2019 Free Software Foundation, Inc.
   3    Contributed by Bob Wilson (bwilson@tensilica.com) at Tensilica.
   4
   5    This file is part of BFD, the Binary File Descriptor library.
   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, MA 02110-1301,
  20    USA.  */
  21
  22 /* This file holds definitions specific to the Xtensa ELF ABI.  */
  23
  24 #ifndef _ELF_XTENSA_H
  25 #define _ELF_XTENSA_H
  26
  27 #include "elf/reloc-macros.h"
  28
  29 #ifdef __cplusplus
  30 extern "C" {
  31 #endif
  32
  33 /* Relocations.  */
  34 START_RELOC_NUMBERS (elf_xtensa_reloc_type)
  35      RELOC_NUMBER (R_XTENSA_NONE, 0)
  36      RELOC_NUMBER (R_XTENSA_32, 1)
  37      RELOC_NUMBER (R_XTENSA_RTLD, 2)
  38      RELOC_NUMBER (R_XTENSA_GLOB_DAT, 3)
  39      RELOC_NUMBER (R_XTENSA_JMP_SLOT, 4)
  40      RELOC_NUMBER (R_XTENSA_RELATIVE, 5)
  41      RELOC_NUMBER (R_XTENSA_PLT, 6)
  42      RELOC_NUMBER (R_XTENSA_OP0, 8)
  43      RELOC_NUMBER (R_XTENSA_OP1, 9)
  44      RELOC_NUMBER (R_XTENSA_OP2, 10)
  45      RELOC_NUMBER (R_XTENSA_ASM_EXPAND, 11)
  46      RELOC_NUMBER (R_XTENSA_ASM_SIMPLIFY, 12)
  47      RELOC_NUMBER (R_XTENSA_32_PCREL, 14)
  48      RELOC_NUMBER (R_XTENSA_GNU_VTINHERIT, 15)
  49      RELOC_NUMBER (R_XTENSA_GNU_VTENTRY, 16)
  50      RELOC_NUMBER (R_XTENSA_DIFF8, 17)
  51      RELOC_NUMBER (R_XTENSA_DIFF16, 18)
  52      RELOC_NUMBER (R_XTENSA_DIFF32, 19)
  53      RELOC_NUMBER (R_XTENSA_SLOT0_OP, 20)
  54      RELOC_NUMBER (R_XTENSA_SLOT1_OP, 21)
  55      RELOC_NUMBER (R_XTENSA_SLOT2_OP, 22)
  56      RELOC_NUMBER (R_XTENSA_SLOT3_OP, 23)
  57      RELOC_NUMBER (R_XTENSA_SLOT4_OP, 24)
  58      RELOC_NUMBER (R_XTENSA_SLOT5_OP, 25)
  59      RELOC_NUMBER (R_XTENSA_SLOT6_OP, 26)
  60      RELOC_NUMBER (R_XTENSA_SLOT7_OP, 27)
  61      RELOC_NUMBER (R_XTENSA_SLOT8_OP, 28)
  62      RELOC_NUMBER (R_XTENSA_SLOT9_OP, 29)
  63      RELOC_NUMBER (R_XTENSA_SLOT10_OP, 30)
  64      RELOC_NUMBER (R_XTENSA_SLOT11_OP, 31)
  65      RELOC_NUMBER (R_XTENSA_SLOT12_OP, 32)
  66      RELOC_NUMBER (R_XTENSA_SLOT13_OP, 33)
  67      RELOC_NUMBER (R_XTENSA_SLOT14_OP, 34)
  68      RELOC_NUMBER (R_XTENSA_SLOT0_ALT, 35)
  69      RELOC_NUMBER (R_XTENSA_SLOT1_ALT, 36)
  70      RELOC_NUMBER (R_XTENSA_SLOT2_ALT, 37)
  71      RELOC_NUMBER (R_XTENSA_SLOT3_ALT, 38)
  72      RELOC_NUMBER (R_XTENSA_SLOT4_ALT, 39)
  73      RELOC_NUMBER (R_XTENSA_SLOT5_ALT, 40)
  74      RELOC_NUMBER (R_XTENSA_SLOT6_ALT, 41)
  75      RELOC_NUMBER (R_XTENSA_SLOT7_ALT, 42)
  76      RELOC_NUMBER (R_XTENSA_SLOT8_ALT, 43)
  77      RELOC_NUMBER (R_XTENSA_SLOT9_ALT, 44)
  78      RELOC_NUMBER (R_XTENSA_SLOT10_ALT, 45)
  79      RELOC_NUMBER (R_XTENSA_SLOT11_ALT, 46)
  80      RELOC_NUMBER (R_XTENSA_SLOT12_ALT, 47)
  81      RELOC_NUMBER (R_XTENSA_SLOT13_ALT, 48)
  82      RELOC_NUMBER (R_XTENSA_SLOT14_ALT, 49)
  83      RELOC_NUMBER (R_XTENSA_TLSDESC_FN, 50)
  84      RELOC_NUMBER (R_XTENSA_TLSDESC_ARG, 51)
  85      RELOC_NUMBER (R_XTENSA_TLS_DTPOFF, 52)
  86      RELOC_NUMBER (R_XTENSA_TLS_TPOFF, 53)
  87      RELOC_NUMBER (R_XTENSA_TLS_FUNC, 54)
  88      RELOC_NUMBER (R_XTENSA_TLS_ARG, 55)
  89      RELOC_NUMBER (R_XTENSA_TLS_CALL, 56)
  90 END_RELOC_NUMBERS (R_XTENSA_max)
  91
  92 /* Processor-specific flags for the ELF header e_flags field.  */
  93
  94 /* Four-bit Xtensa machine type field.  */
  95 #define EF_XTENSA_MACH                  0x0000000f
  96
  97 /* Various CPU types.  */
  98 #define E_XTENSA_MACH                   0x00000000
  99
 100 /* Leave bits 0xf0 alone in case we ever have more than 16 cpu types.
 101    Highly unlikely, but what the heck.  */
 102
 103 #define EF_XTENSA_XT_INSN               0x00000100
 104 #define EF_XTENSA_XT_LIT                0x00000200
 105
 106
 107 /* Processor-specific dynamic array tags.  */
 108
 109 /* Offset of the table that records the GOT location(s).  */
 110 #define DT_XTENSA_GOT_LOC_OFF           0x70000000
 111
 112 /* Number of entries in the GOT location table.  */
 113 #define DT_XTENSA_GOT_LOC_SZ            0x70000001
 114
 115
 116 /* Definitions for instruction and literal property tables.  The
 117    tables for ".gnu.linkonce.*" sections are placed in the following
 118    sections:
 119
 120    instruction tables:  .gnu.linkonce.x.*
 121    literal tables:      .gnu.linkonce.p.*
 122 */
 123
 124 #define XTENSA_INSN_SEC_NAME ".xt.insn"
 125 #define XTENSA_LIT_SEC_NAME  ".xt.lit"
 126 #define XTENSA_PROP_SEC_NAME ".xt.prop"
 127
 128 typedef struct property_table_entry_t
 129 {
 130   bfd_vma address;
 131   bfd_vma size;
 132   flagword flags;
 133 } property_table_entry;
 134
 135 /* Flags in the property tables to specify whether blocks of memory are
 136    literals, instructions, data, or unreachable.  For instructions,
 137    blocks that begin loop targets and branch targets are designated.
 138    Blocks that do not allow density instructions, instruction reordering
 139    or transformation are also specified.  Finally, for branch targets,
 140    branch target alignment priority is included.  Alignment of the next
 141    block is specified in the current block and the size of the current
 142    block does not include any fill required to align to the next
 143    block.  */
 144
 145 #define XTENSA_PROP_LITERAL             0x00000001
 146 #define XTENSA_PROP_INSN                0x00000002
 147 #define XTENSA_PROP_DATA                0x00000004
 148 #define XTENSA_PROP_UNREACHABLE         0x00000008
 149 /* Instruction-only properties at beginning of code. */
 150 #define XTENSA_PROP_INSN_LOOP_TARGET    0x00000010
 151 #define XTENSA_PROP_INSN_BRANCH_TARGET  0x00000020
 152 /* Instruction-only properties about code. */
 153 #define XTENSA_PROP_INSN_NO_DENSITY     0x00000040
 154 #define XTENSA_PROP_INSN_NO_REORDER     0x00000080
 155 /* Historically, NO_TRANSFORM was a property of instructions,
 156    but it should apply to literals under certain circumstances.  */
 157 #define XTENSA_PROP_NO_TRANSFORM        0x00000100
 158
 159 /*  Branch target alignment information.  This transmits information
 160     to the linker optimization about the priority of aligning a
 161     particular block for branch target alignment: None, low priority,
 162     high priority, or required.  These only need to be checked in
 163     instruction blocks marked as XTENSA_PROP_INSN_BRANCH_TARGET.
 164     Common usage is:
 165
 166     switch (GET_XTENSA_PROP_BT_ALIGN(flags))
 167     case XTENSA_PROP_BT_ALIGN_NONE:
 168     case XTENSA_PROP_BT_ALIGN_LOW:
 169     case XTENSA_PROP_BT_ALIGN_HIGH:
 170     case XTENSA_PROP_BT_ALIGN_REQUIRE:
 171 */
 172 #define XTENSA_PROP_BT_ALIGN_MASK       0x00000600
 173
 174 /* No branch target alignment.  */
 175 #define XTENSA_PROP_BT_ALIGN_NONE       0x0
 176 /* Low priority branch target alignment.  */
 177 #define XTENSA_PROP_BT_ALIGN_LOW        0x1
 178 /* High priority branch target alignment. */
 179 #define XTENSA_PROP_BT_ALIGN_HIGH       0x2
 180 /* Required branch target alignment.  */
 181 #define XTENSA_PROP_BT_ALIGN_REQUIRE    0x3
 182
 183 #define GET_XTENSA_PROP_BT_ALIGN(flag) \
 184   (((unsigned)((flag) & (XTENSA_PROP_BT_ALIGN_MASK))) >> 9)
 185 #define SET_XTENSA_PROP_BT_ALIGN(flag, align) \
 186   (((flag) & (~XTENSA_PROP_BT_ALIGN_MASK)) | \
 187     (((align) << 9) & XTENSA_PROP_BT_ALIGN_MASK))
 188
 189 /* Alignment is specified in the block BEFORE the one that needs
 190    alignment.  Up to 5 bits.  Use GET_XTENSA_PROP_ALIGNMENT(flags) to
 191    get the required alignment specified as a power of 2.  Use
 192    SET_XTENSA_PROP_ALIGNMENT(flags, pow2) to set the required
 193    alignment.  Be careful of side effects since the SET will evaluate
 194    flags twice.  Also, note that the SIZE of a block in the property
 195    table does not include the alignment size, so the alignment fill
 196    must be calculated to determine if two blocks are contiguous.
 197    TEXT_ALIGN is not currently implemented but is a placeholder for a
 198    possible future implementation.  */
 199
 200 #define XTENSA_PROP_ALIGN               0x00000800
 201
 202 #define XTENSA_PROP_ALIGNMENT_MASK      0x0001f000
 203
 204 #define GET_XTENSA_PROP_ALIGNMENT(flag) \
 205   (((unsigned)((flag) & (XTENSA_PROP_ALIGNMENT_MASK))) >> 12)
 206 #define SET_XTENSA_PROP_ALIGNMENT(flag, align) \
 207   (((flag) & (~XTENSA_PROP_ALIGNMENT_MASK)) | \
 208     (((align) << 12) & XTENSA_PROP_ALIGNMENT_MASK))
 209
 210 #define XTENSA_PROP_INSN_ABSLIT        0x00020000
 211
 212 extern asection *xtensa_make_property_section (asection *, const char *);
 213 extern int
 214 xtensa_read_table_entries (bfd *abfd,
 215                            asection *section,
 216                            property_table_entry **table_p,
 217                            const char *sec_name,
 218                            bfd_boolean output_addr);
 219 extern int
 220 xtensa_compute_fill_extra_space (property_table_entry *entry);
 221
 222 #ifdef __cplusplus
 223 }
 224 #endif
 225
 226 #endif /* _ELF_XTENSA_H */