| blob | bbf54a4d672cec2cd1fdfb9b93b91736411eebc7 |
1 /* PowerPC-specific support for 32-bit ELF
2 Copyright 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
3 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
4 Free Software Foundation, Inc.
5 Written by Ian Lance Taylor, Cygnus Support.
7 This file is part of BFD, the Binary File Descriptor library.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the
21 Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
22 Boston, MA 02110-1301, USA. */
25 /* This file is based on a preliminary PowerPC ELF ABI. The
26 information may not match the final PowerPC ELF ABI. It includes
27 suggestions from the in-progress Embedded PowerPC ABI, and that
28 information may also not match. */
31 #include <stdarg.h>
41 /* RELA relocations are used here. */
43 static bfd_reloc_status_type ppc_elf_addr16_ha_reloc
45 static bfd_reloc_status_type ppc_elf_unhandled_reloc
48 /* Branch prediction bit for branch taken relocs. */
49 #define BRANCH_PREDICT_BIT 0x200000
50 /* Mask to set RA in memory instructions. */
51 #define RA_REGISTER_MASK 0x001f0000
52 /* Value to shift register by to insert RA. */
53 #define RA_REGISTER_SHIFT 16
55 /* The name of the dynamic interpreter. This is put in the .interp
56 section. */
59 /* For old-style PLT. */
60 /* The number of single-slot PLT entries (the rest use two slots). */
61 #define PLT_NUM_SINGLE_ENTRIES 8192
63 /* For new-style .glink and .plt. */
64 #define GLINK_PLTRESOLVE 16*4
65 #define GLINK_ENTRY_SIZE 4*4
66 #define TLS_GET_ADDR_GLINK_SIZE 12*4
68 /* VxWorks uses its own plt layout, filled in by the static linker. */
70 /* The standard VxWorks PLT entry. */
71 #define VXWORKS_PLT_ENTRY_SIZE 32
72 static const bfd_vma ppc_elf_vxworks_plt_entry
74 {
83 };
84 static const bfd_vma ppc_elf_vxworks_pic_plt_entry
86 {
95 };
97 /* The initial VxWorks PLT entry. */
98 #define VXWORKS_PLT_INITIAL_ENTRY_SIZE 32
99 static const bfd_vma ppc_elf_vxworks_plt0_entry
101 {
110 };
111 static const bfd_vma ppc_elf_vxworks_pic_plt0_entry
113 {
122 };
124 /* For executables, we have some additional relocations in
125 .rela.plt.unloaded, for the kernel loader. */
127 /* The number of non-JMP_SLOT relocations per PLT0 slot. */
128 #define VXWORKS_PLT_NON_JMP_SLOT_RELOCS 3
129 /* The number of relocations in the PLTResolve slot. */
130 #define VXWORKS_PLTRESOLVE_RELOCS 2
131 /* The number of relocations in the PLTResolve slot when when creating
132 a shared library. */
133 #define VXWORKS_PLTRESOLVE_RELOCS_SHLIB 0
135 /* Some instructions. */
136 #define ADDIS_11_11 0x3d6b0000
137 #define ADDIS_11_30 0x3d7e0000
138 #define ADDIS_12_12 0x3d8c0000
139 #define ADDI_11_11 0x396b0000
140 #define ADD_0_11_11 0x7c0b5a14
141 #define ADD_3_12_2 0x7c6c1214
142 #define ADD_11_0_11 0x7d605a14
143 #define B 0x48000000
144 #define BCL_20_31 0x429f0005
145 #define BCTR 0x4e800420
146 #define BEQLR 0x4d820020
147 #define CMPWI_11_0 0x2c0b0000
148 #define LIS_11 0x3d600000
149 #define LIS_12 0x3d800000
150 #define LWZU_0_12 0x840c0000
151 #define LWZ_0_12 0x800c0000
152 #define LWZ_11_3 0x81630000
153 #define LWZ_11_11 0x816b0000
154 #define LWZ_11_30 0x817e0000
155 #define LWZ_12_3 0x81830000
156 #define LWZ_12_12 0x818c0000
157 #define MR_0_3 0x7c601b78
158 #define MR_3_0 0x7c030378
159 #define MFLR_0 0x7c0802a6
160 #define MFLR_12 0x7d8802a6
161 #define MTCTR_0 0x7c0903a6
162 #define MTCTR_11 0x7d6903a6
163 #define MTLR_0 0x7c0803a6
164 #define NOP 0x60000000
165 #define SUB_11_11_12 0x7d6c5850
167 /* Offset of tp and dtp pointers from start of TLS block. */
168 #define TP_OFFSET 0x7000
169 #define DTP_OFFSET 0x8000
171 /* The value of a defined global symbol. */
172 #define SYM_VAL(SYM) \
173 ((SYM)->root.u.def.section->output_section->vma \
174 + (SYM)->root.u.def.section->output_offset \
175 + (SYM)->root.u.def.value)
176 \f
180 /* This reloc does nothing. */
195 /* A standard 32 bit relocation. */
210 /* An absolute 26 bit branch; the lower two bits must be zero.
211 FIXME: we don't check that, we just clear them. */
226 /* A standard 16 bit relocation. */
241 /* A 16 bit relocation without overflow. */
256 /* The high order 16 bits of an address. */
271 /* The high order 16 bits of an address, plus 1 if the contents of
272 the low 16 bits, treated as a signed number, is negative. */
287 /* An absolute 16 bit branch; the lower two bits must be zero.
288 FIXME: we don't check that, we just clear them. */
303 /* An absolute 16 bit branch, for which bit 10 should be set to
304 indicate that the branch is expected to be taken. The lower two
305 bits must be zero. */
320 /* An absolute 16 bit branch, for which bit 10 should be set to
321 indicate that the branch is not expected to be taken. The lower
322 two bits must be zero. */
337 /* A relative 26 bit branch; the lower two bits must be zero. */
352 /* A relative 16 bit branch; the lower two bits must be zero. */
367 /* A relative 16 bit branch. Bit 10 should be set to indicate that
368 the branch is expected to be taken. The lower two bits must be
369 zero. */
384 /* A relative 16 bit branch. Bit 10 should be set to indicate that
385 the branch is not expected to be taken. The lower two bits must
386 be zero. */
401 /* Like R_PPC_ADDR16, but referring to the GOT table entry for the
402 symbol. */
417 /* Like R_PPC_ADDR16_LO, but referring to the GOT table entry for
418 the symbol. */
433 /* Like R_PPC_ADDR16_HI, but referring to the GOT table entry for
434 the symbol. */
449 /* Like R_PPC_ADDR16_HA, but referring to the GOT table entry for
450 the symbol. */
465 /* Like R_PPC_REL24, but referring to the procedure linkage table
466 entry for the symbol. */
481 /* This is used only by the dynamic linker. The symbol should exist
482 both in the object being run and in some shared library. The
483 dynamic linker copies the data addressed by the symbol from the
484 shared library into the object, because the object being
485 run has to have the data at some particular address. */
500 /* Like R_PPC_ADDR32, but used when setting global offset table
501 entries. */
516 /* Marks a procedure linkage table entry for a symbol. */
531 /* Used only by the dynamic linker. When the object is run, this
532 longword is set to the load address of the object, plus the
533 addend. */
548 /* Like R_PPC_REL24, but uses the value of the symbol within the
549 object rather than the final value. Normally used for
550 _GLOBAL_OFFSET_TABLE_. */
565 /* Like R_PPC_ADDR32, but may be unaligned. */
580 /* Like R_PPC_ADDR16, but may be unaligned. */
595 /* 32-bit PC relative */
610 /* 32-bit relocation to the symbol's procedure linkage table.
611 FIXME: not supported. */
626 /* 32-bit PC relative relocation to the symbol's procedure linkage table.
627 FIXME: not supported. */
642 /* Like R_PPC_ADDR16_LO, but referring to the PLT table entry for
643 the symbol. */
658 /* Like R_PPC_ADDR16_HI, but referring to the PLT table entry for
659 the symbol. */
674 /* Like R_PPC_ADDR16_HA, but referring to the PLT table entry for
675 the symbol. */
690 /* A sign-extended 16 bit value relative to _SDA_BASE_, for use with
691 small data items. */
706 /* 16-bit section relative relocation. */
721 /* 16-bit lower half section relative relocation. */
736 /* 16-bit upper half section relative relocation. */
751 /* 16-bit upper half adjusted section relative relocation. */
766 /* Marker relocs for TLS. */
809 /* Computes the load module index of the load module that contains the
810 definition of its TLS sym. */
825 /* Computes a dtv-relative displacement, the difference between the value
826 of sym+add and the base address of the thread-local storage block that
827 contains the definition of sym, minus 0x8000. */
842 /* A 16 bit dtprel reloc. */
857 /* Like DTPREL16, but no overflow. */
872 /* Like DTPREL16_LO, but next higher group of 16 bits. */
887 /* Like DTPREL16_HI, but adjust for low 16 bits. */
902 /* Computes a tp-relative displacement, the difference between the value of
903 sym+add and the value of the thread pointer (r13). */
918 /* A 16 bit tprel reloc. */
933 /* Like TPREL16, but no overflow. */
948 /* Like TPREL16_LO, but next higher group of 16 bits. */
963 /* Like TPREL16_HI, but adjust for low 16 bits. */
978 /* Allocates two contiguous entries in the GOT to hold a tls_index structure,
979 with values (sym+add)@dtpmod and (sym+add)@dtprel, and computes the offset
980 to the first entry. */
995 /* Like GOT_TLSGD16, but no overflow. */
1010 /* Like GOT_TLSGD16_LO, but next higher group of 16 bits. */
1025 /* Like GOT_TLSGD16_HI, but adjust for low 16 bits. */
1040 /* Allocates two contiguous entries in the GOT to hold a tls_index structure,
1041 with values (sym+add)@dtpmod and zero, and computes the offset to the
1042 first entry. */
1057 /* Like GOT_TLSLD16, but no overflow. */
1072 /* Like GOT_TLSLD16_LO, but next higher group of 16 bits. */
1087 /* Like GOT_TLSLD16_HI, but adjust for low 16 bits. */
1102 /* Allocates an entry in the GOT with value (sym+add)@dtprel, and computes
1103 the offset to the entry. */
1118 /* Like GOT_DTPREL16, but no overflow. */
1133 /* Like GOT_DTPREL16_LO, but next higher group of 16 bits. */
1148 /* Like GOT_DTPREL16_HI, but adjust for low 16 bits. */
1163 /* Allocates an entry in the GOT with value (sym+add)@tprel, and computes the
1164 offset to the entry. */
1179 /* Like GOT_TPREL16, but no overflow. */
1194 /* Like GOT_TPREL16_LO, but next higher group of 16 bits. */
1209 /* Like GOT_TPREL16_HI, but adjust for low 16 bits. */
1224 /* The remaining relocs are from the Embedded ELF ABI, and are not
1225 in the SVR4 ELF ABI. */
1227 /* 32 bit value resulting from the addend minus the symbol. */
1242 /* 16 bit value resulting from the addend minus the symbol. */
1257 /* 16 bit value resulting from the addend minus the symbol. */
1272 /* The high order 16 bits of the addend minus the symbol. */
1287 /* The high order 16 bits of the result of the addend minus the address,
1288 plus 1 if the contents of the low 16 bits, treated as a signed number,
1289 is negative. */
1304 /* 16 bit value resulting from allocating a 4 byte word to hold an
1305 address in the .sdata section, and returning the offset from
1306 _SDA_BASE_ for that relocation. */
1321 /* 16 bit value resulting from allocating a 4 byte word to hold an
1322 address in the .sdata2 section, and returning the offset from
1323 _SDA2_BASE_ for that relocation. */
1338 /* A sign-extended 16 bit value relative to _SDA2_BASE_, for use with
1339 small data items. */
1354 /* Relocate against either _SDA_BASE_ or _SDA2_BASE_, filling in the 16 bit
1355 signed offset from the appropriate base, and filling in the register
1356 field with the appropriate register (0, 2, or 13). */
1371 /* Relocation not handled: R_PPC_EMB_MRKREF */
1372 /* Relocation not handled: R_PPC_EMB_RELSEC16 */
1373 /* Relocation not handled: R_PPC_EMB_RELST_LO */
1374 /* Relocation not handled: R_PPC_EMB_RELST_HI */
1375 /* Relocation not handled: R_PPC_EMB_RELST_HA */
1376 /* Relocation not handled: R_PPC_EMB_BIT_FLD */
1378 /* PC relative relocation against either _SDA_BASE_ or _SDA2_BASE_, filling
1379 in the 16 bit signed offset from the appropriate base, and filling in the
1380 register field with the appropriate register (0, 2, or 13). */
1409 /* A 16 bit relative relocation. */
1424 /* A 16 bit relative relocation without overflow. */
1439 /* The high order 16 bits of a relative address. */
1454 /* The high order 16 bits of a relative address, plus 1 if the contents of
1455 the low 16 bits, treated as a signed number, is negative. */
1470 /* GNU extension to record C++ vtable hierarchy. */
1485 /* GNU extension to record C++ vtable member usage. */
1500 /* Phony reloc to handle AIX style TOC entries. */
1514 };
1515 \f
1516 /* Initialize the ppc_elf_howto_table, so that linear accesses can be done. */
1518 static void
1520 {
1525 i++)
1526 {
1532 }
1533 }
1537 bfd_reloc_code_real_type code)
1538 {
1541 /* Initialize howto table if not already done. */
1546 {
1637 }
1640 };
1645 {
1650 i++)
1656 }
1658 /* Set the howto pointer for a PowerPC ELF reloc. */
1660 static void
1664 {
1665 /* Initialize howto table if not already done. */
1672 /* Just because the above assert didn't trigger doesn't mean that
1673 ELF32_R_TYPE (dst->r_info) is necessarily a valid relocation. */
1675 {
1681 }
1682 }
1684 /* Handle the R_PPC_ADDR16_HA and R_PPC_REL16_HA relocs. */
1686 static bfd_reloc_status_type
1694 {
1695 bfd_vma relocation;
1698 {
1701 }
1708 else
1720 }
1722 static bfd_reloc_status_type
1730 {
1731 /* If this is a relocatable link (output_bfd test tells us), just
1732 call the generic function. Any adjustment will be done at final
1733 link time. */
1739 {
1744 }
1746 }
1747 \f
1748 /* Sections created by the linker. */
1751 {
1752 /* Pointer to the bfd section. */
1754 /* Section name. */
1756 /* Associated bss section name. */
1758 /* Associated symbol name. */
1760 /* Associated symbol. */
1764 /* Linked list of allocated pointer entries. This hangs off of the
1765 symbol lists, and provides allows us to return different pointers,
1766 based on different addend's. */
1769 {
1770 /* next allocated pointer for this symbol */
1772 /* offset of pointer from beginning of section */
1773 bfd_vma offset;
1774 /* addend used */
1775 bfd_vma addend;
1776 /* which linker section this is */
1780 struct ppc_elf_obj_tdata
1781 {
1784 /* A mapping from local symbols to offsets into the various linker
1785 sections added. This is index by the symbol index. */
1788 /* Flags used to auto-detect plt type. */
1791 };
1793 #define ppc_elf_tdata(bfd) \
1794 ((struct ppc_elf_obj_tdata *) (bfd)->tdata.any)
1796 #define elf_local_ptr_offsets(bfd) \
1797 (ppc_elf_tdata (bfd)->linker_section_pointers)
1799 #define is_ppc_elf(bfd) \
1800 (bfd_get_flavour (bfd) == bfd_target_elf_flavour \
1801 && elf_object_id (bfd) == PPC32_ELF_DATA)
1803 /* Override the generic function because we store some extras. */
1805 static bfd_boolean
1807 {
1809 PPC32_ELF_DATA);
1810 }
1812 /* Fix bad default arch selected for a 32 bit input bfd when the
1813 default is 64 bit. */
1815 static bfd_boolean
1817 {
1819 {
1823 {
1824 /* Relies on arch after 64 bit default being 32 bit default. */
1827 }
1828 }
1830 }
1832 /* Function to set whether a module needs the -mrelocatable bit set. */
1834 static bfd_boolean
1836 {
1843 }
1845 /* Support for core dump NOTE sections. */
1847 static bfd_boolean
1849 {
1854 {
1859 /* pr_cursig */
1862 /* pr_pid */
1865 /* pr_reg */
1870 }
1872 /* Make a ".reg/999" section. */
1875 }
1877 static bfd_boolean
1879 {
1881 {
1892 }
1894 /* Note that for some reason, a spurious space is tacked
1895 onto the end of the args in some (at least one anyway)
1896 implementations, so strip it off if it exists. */
1898 {
1904 }
1907 }
1911 {
1913 {
1918 {
1929 }
1932 {
1951 }
1952 }
1953 }
1955 /* Return address for Ith PLT stub in section PLT, for relocation REL
1956 or (bfd_vma) -1 if it should not be included. */
1958 static bfd_vma
1962 {
1964 }
1966 /* Handle a PowerPC specific section when reading an object file. This
1967 is called when bfd_section_from_shdr finds a section with an unknown
1968 type. */
1970 static bfd_boolean
1975 {
1977 flagword flags;
1992 }
1994 /* Set up any other section flags and such that may be necessary. */
1996 static bfd_boolean
2000 {
2005 }
2007 /* If we have .sbss2 or .PPC.EMB.sbss0 output sections, we
2008 need to bump up the number of section headers. */
2010 static int
2013 {
2026 }
2028 /* Add extra PPC sections -- Note, for now, make .sbss2 and
2029 .PPC.EMB.sbss0 a normal section, and not a bss section so
2030 that the linker doesn't crater when trying to make more than
2031 2 sections. */
2034 {
2045 };
2047 /* This is what we want for new plt/got. */
2053 {
2056 /* See if this is one of the special sections. */
2063 {
2067 }
2070 }
2071 \f
2072 /* Very simple linked list structure for recording apuinfo values. */
2074 {
2077 }
2078 apuinfo_list;
2083 static void
2085 {
2088 }
2090 static void
2092 {
2096 {
2100 }
2109 }
2111 static unsigned
2113 {
2118 entry;
2123 }
2127 {
2133 ;
2136 }
2138 static void
2140 {
2144 {
2148 }
2151 }
2156 /* Scan the input BFDs and create a linked list of
2157 the APUinfo values that will need to be emitted. */
2159 static void
2161 {
2175 /* Read in the input sections contents. */
2177 {
2191 {
2198 }
2202 {
2205 }
2207 /* Verify the contents of the header. Note - we have to
2208 extract the values this way in order to allow for a
2209 host whose endian-ness is different from the target. */
2221 /* Get the number of bytes used for apuinfo entries. */
2226 /* Scan the apuinfo section, building a list of apuinfo numbers. */
2229 }
2234 {
2235 /* Compute the size of the output section. */
2238 /* Set the output section size, if it exists. */
2242 {
2245 }
2246 }
2248 fail:
2254 }
2256 /* Prevent the output section from accumulating the input sections'
2257 contents. We have already stored this in our linked list structure. */
2259 static bfd_boolean
2264 {
2266 }
2268 /* Finally we can generate the output section. */
2270 static void
2272 {
2277 bfd_size_type length;
2292 {
2296 }
2298 /* Create the apuinfo header. */
2307 {
2310 }
2321 }
2322 \f
2323 static bfd_boolean
2325 {
2335 }
2337 static bfd_boolean
2339 {
2344 }
2346 static long
2350 {
2355 bfd_vma stub_vma;
2379 /* Call common code to handle old-style executable PLTs. */
2384 /* If this object was prelinked, the prelinker stored the address
2385 of .glink at got[1]. If it wasn't prelinked, got[1] will be zero. */
2388 {
2402 {
2403 Elf_Internal_Dyn dyn;
2410 {
2418 }
2419 }
2421 }
2423 /* Otherwise we read the first plt entry. */
2425 {
2428 }
2433 /* The .glink section usually does not survive the final
2434 link; search for the section (usually .text) where the
2435 glink stubs now reside. */
2440 /* Determine glink PLT resolver by reading the relative branch
2441 from the first glink stub. */
2444 {
2447 /* The first glink stub may either branch to the resolver ... */
2452 /* ... or fall through a bunch of NOPs. */
2459 {
2462 }
2463 }
2467 /* If the stubs are those for -shared/-pie then we might have
2468 multiple stubs for each plt entry. If that is the case then
2469 there is no way to associate stubs with their plt entries short
2470 of figuring out the GOT pointer value used in the stub. */
2482 {
2486 }
2500 {
2504 /* Undefined syms won't have BSF_LOCAL or BSF_GLOBAL set. Since
2505 we are defining a symbol, ensure one of them is set. */
2517 {
2522 }
2527 }
2529 /* Add a symbol at the start of the glink branch table. */
2538 s++;
2539 count++;
2542 {
2543 /* Add a symbol for the glink PLT resolver. */
2552 s++;
2553 count++;
2554 }
2557 }
2558 \f
2559 /* The following functions are specific to the ELF linker, while
2560 functions above are used generally. They appear in this file more
2561 or less in the order in which they are called. eg.
2562 ppc_elf_check_relocs is called early in the link process,
2563 ppc_elf_finish_dynamic_sections is one of the last functions
2564 called. */
2566 /* Track PLT entries needed for a given symbol. We might need more
2567 than one glink entry per symbol when generating a pic binary. */
2568 struct plt_entry
2569 {
2572 /* -fPIC uses multiple GOT sections, one per file, called ".got2".
2573 This field stores the offset into .got2 used to initialise the
2574 GOT pointer reg. It will always be at least 32768. (Current
2575 gcc always uses an offset of 32768, but ld -r will pack .got2
2576 sections together resulting in larger offsets). */
2577 bfd_vma addend;
2579 /* The .got2 section. */
2582 /* PLT refcount or offset. */
2583 union
2584 {
2585 bfd_signed_vma refcount;
2586 bfd_vma offset;
2589 /* .glink stub offset. */
2590 bfd_vma glink_offset;
2591 };
2593 /* Of those relocs that might be copied as dynamic relocs, this function
2594 selects those that must be copied when linking a shared library,
2595 even when the symbol is local. */
2597 static int
2600 {
2602 {
2619 }
2620 }
2622 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
2623 copying dynamic variables from a shared lib into an app's dynbss
2624 section, and instead use a dynamic relocation to point into the
2625 shared lib. */
2626 #define ELIMINATE_COPY_RELOCS 1
2628 /* PPC ELF linker hash entry. */
2630 struct ppc_elf_link_hash_entry
2631 {
2634 /* If this symbol is used in the linker created sections, the processor
2635 specific backend uses this field to map the field into the offset
2636 from the beginning of the section. */
2639 /* Track dynamic relocs copied for this symbol. */
2642 /* Contexts in which symbol is used in the GOT (or TOC).
2643 TLS_GD .. TLS_TLS bits are or'd into the mask as the
2644 corresponding relocs are encountered during check_relocs.
2645 tls_optimize clears TLS_GD .. TLS_TPREL when optimizing to
2646 indicate the corresponding GOT entry type is not needed. */
2656 /* Nonzero if we have seen a small data relocation referring to this
2657 symbol. */
2659 };
2661 #define ppc_elf_hash_entry(ent) ((struct ppc_elf_link_hash_entry *) (ent))
2663 /* PPC ELF linker hash table. */
2665 struct ppc_elf_link_hash_table
2666 {
2669 /* Short-cuts to get to dynamic linker sections. */
2685 /* The (unloaded but important) .rela.plt.unloaded on VxWorks. */
2688 /* The .got.plt section (VxWorks only)*/
2691 /* Shortcut to __tls_get_addr. */
2694 /* The bfd that forced an old-style PLT. */
2697 /* TLS local dynamic got entry handling. */
2699 bfd_signed_vma refcount;
2700 bfd_vma offset;
2703 /* Offset of branch table to PltResolve function in glink. */
2704 bfd_vma glink_pltresolve;
2706 /* Size of reserved GOT entries. */
2708 /* Non-zero if allocating the header left a gap. */
2711 /* The type of PLT we have chosen to use. */
2714 /* Set if we should emit symbols for stubs. */
2717 /* Set if __tls_get_addr optimization should not be done. */
2720 /* True if the target system is VxWorks. */
2723 /* The size of PLT entries. */
2725 /* The distance between adjacent PLT slots. */
2727 /* The size of the first PLT entry. */
2730 /* Small local sym cache. */
2732 };
2734 /* Rename some of the generic section flags to better document how they
2735 are used here. */
2737 /* Nonzero if this section has TLS related relocations. */
2738 #define has_tls_reloc sec_flg0
2740 /* Nonzero if this section has a call to __tls_get_addr. */
2741 #define has_tls_get_addr_call sec_flg1
2743 /* Get the PPC ELF linker hash table from a link_info structure. */
2745 #define ppc_elf_hash_table(p) \
2746 (elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) \
2747 == PPC32_ELF_DATA ? ((struct ppc_elf_link_hash_table *) ((p)->hash)) : NULL)
2749 /* Create an entry in a PPC ELF linker hash table. */
2755 {
2756 /* Allocate the structure if it has not already been allocated by a
2757 subclass. */
2759 {
2764 }
2766 /* Call the allocation method of the superclass. */
2769 {
2774 }
2777 }
2779 /* Create a PPC ELF linker hash table. */
2783 {
2791 ppc_elf_link_hash_newfunc,
2793 PPC32_ELF_DATA))
2794 {
2797 }
2817 }
2819 /* Create .got and the related sections. */
2821 static bfd_boolean
2823 {
2826 flagword flags;
2837 {
2841 }
2842 else
2843 {
2844 /* The powerpc .got has a blrl instruction in it. Mark it
2845 executable. */
2850 }
2857 }
2859 static bfd_boolean
2861 {
2864 flagword flags;
2875 {
2883 }
2900 }
2902 /* We have to create .dynsbss and .rela.sbss here so that they get mapped
2903 to output sections (just like _bfd_elf_create_dynamic_sections has
2904 to create .dynbss and .rela.bss). */
2906 static bfd_boolean
2908 {
2911 flagword flags;
2934 {
2943 }
2956 /* The VxWorks PLT is a loaded section with contents. */
2959 }
2961 /* Copy the extra info we tack onto an elf_link_hash_entry. */
2963 static void
2967 {
2976 /* If called to transfer flags for a weakdef during processing
2977 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
2978 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
2991 {
2993 {
2997 /* Add reloc counts against the indirect sym to the direct sym
2998 list. Merge any entries against the same section. */
3000 {
3005 {
3010 }
3013 }
3015 }
3019 }
3021 /* If we were called to copy over info for a weak sym, that's all.
3022 You might think dyn_relocs need not be copied over; After all,
3023 both syms will be dynamic or both non-dynamic so we're just
3024 moving reloc accounting around. However, ELIMINATE_COPY_RELOCS
3025 code in ppc_elf_adjust_dynamic_symbol needs to check for
3026 dyn_relocs in read-only sections, and it does so on what is the
3027 DIR sym here. */
3031 /* Copy over the GOT refcount entries that we may have already seen to
3032 the symbol which just became indirect. */
3036 /* And plt entries. */
3038 {
3040 {
3045 {
3050 {
3054 }
3057 }
3059 }
3063 }
3066 {
3074 }
3075 }
3077 /* Hook called by the linker routine which adds symbols from an object
3078 file. We use it to put .comm items in .sbss, and not .bss. */
3080 static bfd_boolean
3088 {
3093 {
3094 /* Common symbols less than or equal to -G nn bytes are automatically
3095 put into .sbss. */
3100 {
3108 flags);
3111 }
3115 }
3123 }
3124 \f
3125 static bfd_boolean
3127 {
3139 }
3141 /* Create a special linker section. */
3143 static bfd_boolean
3146 flagword flags,
3148 {
3155 /* Record the first bfd that needs the special sections. */
3161 flags);
3168 }
3170 /* Find a linker generated pointer with a given addend and type. */
3173 elf_find_pointer_linker_section
3175 bfd_vma addend,
3177 {
3183 }
3185 /* Allocate a pointer to live in a linker created section. */
3187 static bfd_boolean
3192 {
3196 bfd_size_type amt;
3200 /* Is this a global symbol? */
3202 {
3205 /* Has this symbol already been allocated? If so, our work is done. */
3209 lsect))
3213 }
3214 else
3215 {
3218 /* Allocation of a pointer to a local symbol. */
3221 /* Allocate a table to hold the local symbols if first time. */
3223 {
3234 }
3236 /* Has this symbol already been allocated? If so, our work is done. */
3239 lsect))
3243 }
3245 /* Allocate space for a pointer in the linker section, and allocate
3246 a new pointer record from internal memory. */
3262 #ifdef DEBUG
3267 #endif
3270 }
3277 {
3283 {
3293 }
3301 }
3303 static bfd_boolean
3306 {
3315 {
3325 }
3328 }
3332 {
3341 }
3343 static bfd_boolean
3345 {
3356 }
3358 static void
3360 {
3363 abfd,
3366 }
3368 /* Look through the relocs for a section during the first phase, and
3369 allocate space in the global offset table or procedure linkage
3370 table. */
3372 static bfd_boolean
3377 {
3389 /* Don't do anything special with non-loaded, non-alloced sections.
3390 In particular, any relocs in such sections should not affect GOT
3391 and PLT reference counting (ie. we don't allow them to create GOT
3392 or PLT entries), there's no possibility or desire to optimize TLS
3393 relocs, and there's not much point in propagating relocs to shared
3394 libs that the dynamic linker won't relocate. */
3398 #ifdef DEBUG
3401 #endif
3405 /* Initialize howto table if not already done. */
3411 {
3416 }
3426 {
3435 else
3436 {
3441 }
3443 /* If a relocation refers to _GLOBAL_OFFSET_TABLE_, create the .got.
3444 This shows up in particular in an R_PPC_ADDR32 in the eabi
3445 startup code. */
3449 {
3455 }
3460 {
3469 {
3471 bfd_vma addend;
3474 PLT_IFUNC);
3478 /* STT_GNU_IFUNC symbols must have a PLT entry;
3479 In a non-pie executable even when there are
3480 no plt calls. */
3483 {
3487 }
3490 }
3491 }
3497 {
3501 /* We have a new-style __tls_get_addr call with a marker
3502 reloc. */
3503 ;
3504 else
3505 /* Mark this section as having an old-style call. */
3507 }
3510 {
3513 /* These special tls relocs tie a call to __tls_get_addr with
3514 its parameter symbol. */
3545 dogottls:
3547 /* Fall thru */
3549 /* GOT16 relocations */
3554 /* This symbol requires a global offset table entry. */
3556 {
3561 }
3563 {
3566 }
3567 else
3568 /* This is a global offset table entry for a local symbol. */
3572 /* We may also need a plt entry if the symbol turns out to be
3573 an ifunc. */
3575 {
3578 }
3581 /* Indirect .sdata relocation. */
3584 {
3587 }
3596 {
3599 }
3602 /* Indirect .sdata2 relocation. */
3605 {
3608 }
3617 {
3620 }
3628 {
3631 }
3636 {
3639 }
3644 {
3647 }
3653 {
3656 }
3664 {
3667 }
3676 {
3679 }
3687 /* Fall through */
3693 #ifdef DEBUG
3695 #endif
3696 /* This symbol requires a procedure linkage table entry. We
3697 actually build the entry in finish_dynamic_symbol,
3698 because this might be a case of linking PIC code without
3699 linking in any dynamic objects, in which case we don't
3700 need to generate a procedure linkage table after all. */
3703 {
3704 /* It does not make sense to have a procedure linkage
3705 table entry for a local symbol. */
3711 }
3712 else
3713 {
3717 {
3721 }
3725 }
3728 /* The following relocations don't need to propagate the
3729 relocation if linking a shared object since they are
3730 section relative. */
3749 /* These are just markers. */
3759 /* These should only appear in dynamic objects. */
3767 /* These aren't handled yet. We'll report an error later. */
3776 /* This refers only to functions defined in the shared library. */
3779 {
3782 }
3785 /* This relocation describes the C++ object vtable hierarchy.
3786 Reconstruct it for later use during GC. */
3792 /* This relocation describes which C++ vtable entries are actually
3793 used. Record for later use during GC. */
3801 /* We shouldn't really be seeing these. */
3811 /* Nor these. */
3822 {
3823 /* Old -fPIC gcc code has .long LCTOC1-LCFx just before
3824 the start of a function, which assembles to a REL32
3825 reference to .got2. If we detect one of these, then
3826 force the old PLT layout because the linker cannot
3827 reliably deduce the GOT pointer value needed for
3828 PLT call stubs. */
3839 {
3842 }
3843 }
3846 /* fall through */
3856 {
3857 /* We may need a plt entry if the symbol turns out to be
3858 a function defined in a dynamic object. */
3862 /* We may need a copy reloc too. */
3865 }
3875 {
3877 {
3880 }
3882 }
3883 /* fall through */
3890 {
3891 /* We may need a plt entry if the symbol turns out to be
3892 a function defined in a dynamic object. */
3897 }
3899 dodyn:
3900 /* If we are creating a shared library, and this is a reloc
3901 against a global symbol, or a non PC relative reloc
3902 against a local symbol, then we need to copy the reloc
3903 into the shared library. However, if we are linking with
3904 -Bsymbolic, we do not need to copy a reloc against a
3905 global symbol which is defined in an object we are
3906 including in the link (i.e., DEF_REGULAR is set). At
3907 this point we have not seen all the input files, so it is
3908 possible that DEF_REGULAR is not set now but will be set
3909 later (it is never cleared). In case of a weak definition,
3910 DEF_REGULAR may be cleared later by a strong definition in
3911 a shared library. We account for that possibility below by
3912 storing information in the dyn_relocs field of the hash
3913 table entry. A similar situation occurs when creating
3914 shared libraries and symbol visibility changes render the
3915 symbol local.
3917 If on the other hand, we are creating an executable, we
3918 may need to keep relocations for symbols satisfied by a
3919 dynamic library if we manage to avoid copy relocs for the
3920 symbol. */
3927 || (ELIMINATE_COPY_RELOCS
3932 {
3936 #ifdef DEBUG
3938 "ppc_elf_check_relocs needs to "
3942 #endif
3944 {
3948 sreloc = _bfd_elf_make_dynamic_reloc_section
3953 }
3955 /* If this is a global symbol, we count the number of
3956 relocations we need for this symbol. */
3958 {
3960 }
3961 else
3962 {
3963 /* Track dynamic relocs needed for local syms too.
3964 We really need local syms available to do this
3965 easily. Oh well. */
3981 }
3985 {
3994 }
3999 }
4002 }
4003 }
4006 }
4007 \f
4009 /* Merge object attributes from IBFD into OBFD. Raise an error if
4010 there are conflicting attributes. */
4011 static bfd_boolean
4013 {
4018 {
4019 /* This is the first object. Copy the attributes. */
4022 /* Use the Tag_null value to indicate the attributes have been
4023 initialized. */
4027 }
4032 /* Check for conflicting Tag_GNU_Power_ABI_FP attributes and merge
4033 non-conflicting ones. */
4037 {
4042 ;
4044 _bfd_error_handler
4047 _bfd_error_handler
4051 _bfd_error_handler
4055 _bfd_error_handler
4059 _bfd_error_handler
4062 _bfd_error_handler
4065 else
4066 _bfd_error_handler
4069 }
4071 /* Check for conflicting Tag_GNU_Power_ABI_Vector attributes and
4072 merge non-conflicting ones. */
4076 {
4080 {
4084 }
4087 {
4091 }
4097 ;
4098 /* For now, allow generic to transition to AltiVec or SPE
4099 without a warning. If GCC marked files with their stack
4100 alignment and used don't-care markings for files which are
4101 not affected by the vector ABI, we could warn about this
4102 case too. */
4106 ;
4108 _bfd_error_handler
4112 _bfd_error_handler
4115 else
4116 _bfd_error_handler
4119 }
4121 /* Check for conflicting Tag_GNU_Power_ABI_Struct_Return attributes
4122 and merge non-conflicting ones. */
4126 {
4131 ;
4133 _bfd_error_handler
4136 _bfd_error_handler
4139 _bfd_error_handler
4142 else
4143 _bfd_error_handler
4146 }
4148 /* Merge Tag_compatibility attributes and any common GNU ones. */
4152 }
4154 /* Merge backend specific data from an object file to the output
4155 object file when linking. */
4157 static bfd_boolean
4159 {
4160 flagword old_flags;
4161 flagword new_flags;
4162 bfd_boolean error;
4167 /* Check if we have the same endianness. */
4177 {
4178 /* First call, no flags set. */
4181 }
4183 /* Compatible flags are ok. */
4185 ;
4187 /* Incompatible flags. */
4188 else
4189 {
4190 /* Warn about -mrelocatable mismatch. Allow -mrelocatable-lib
4191 to be linked with either. */
4195 {
4200 }
4203 {
4208 }
4210 /* The output is -mrelocatable-lib iff both the input files are. */
4214 /* The output is -mrelocatable iff it can't be -mrelocatable-lib,
4215 but each input file is either -mrelocatable or -mrelocatable-lib. */
4221 /* Do not warn about eabi vs. V.4 mismatch, just or in the bit if
4222 any module uses it. */
4228 /* Warn about any other mismatches. */
4230 {
4236 }
4239 {
4242 }
4243 }
4246 }
4247 \f
4248 /* Choose which PLT scheme to use, and set .plt flags appropriately.
4249 Returns -1 on error, 0 for old PLT, 1 for new PLT. */
4250 int
4255 {
4257 flagword flags;
4264 {
4279 {
4280 /* Profiling of shared libs (and pies) is not supported with
4281 secure plt, because ppc32 does profiling before a
4282 function prologue and a secure plt pic call stubs needs
4283 r30 to be set up. */
4285 }
4286 else
4287 {
4291 /* Look through the reloc flags left by ppc_elf_check_relocs.
4292 Use the old style bss plt if a file makes plt calls
4293 without using the new relocs, and if ld isn't given
4294 --secure-plt and we never see REL16 relocs. */
4299 {
4303 {
4307 }
4308 }
4310 }
4311 }
4313 {
4317 else
4319 }
4324 {
4328 /* The new PLT is a loaded section. */
4333 /* The new GOT is not executable. */
4337 }
4338 else
4339 {
4340 /* Stop an unused .glink section from affecting .text alignment. */
4344 }
4346 }
4347 \f
4348 /* Return the section that should be marked against GC for a given
4349 relocation. */
4357 {
4360 {
4364 }
4367 }
4369 /* Update the got, plt and dynamic reloc reference counts for the
4370 section being removed. */
4372 static bfd_boolean
4377 {
4401 {
4408 {
4420 {
4421 /* Everything must go for SEC. */
4424 }
4425 }
4433 {
4439 {
4450 }
4451 }
4454 {
4476 {
4480 {
4486 }
4487 }
4489 {
4492 }
4502 /* Fall thru */
4525 {
4534 }
4539 }
4540 }
4542 }
4543 \f
4544 /* Set plt output section type, htab->tls_get_addr, and call the
4545 generic ELF tls_setup function. */
4547 asection *
4551 {
4558 {
4565 {
4566 /* If glibc supports an optimized __tls_get_addr call stub,
4567 signalled by the presence of __tls_get_addr_opt, and we'll
4568 be calling __tls_get_addr via a plt call stub, then
4569 make __tls_get_addr point to __tls_get_addr_opt. */
4578 {
4584 {
4589 {
4590 /* Use __tls_get_addr_opt in dynamic relocations. */
4596 }
4598 }
4599 }
4600 }
4601 else
4603 }
4608 {
4611 }
4614 }
4616 /* Return TRUE iff REL is a branch reloc with a global symbol matching
4617 HASH. */
4619 static bfd_boolean
4623 {
4629 {
4639 }
4641 }
4643 /* Run through all the TLS relocs looking for optimization
4644 opportunities. */
4646 bfd_boolean
4649 {
4662 /* Make two passes through the relocs. First time check that tls
4663 relocs involved in setting up a tls_get_addr call are indeed
4664 followed by such a call. If they are not, don't do any tls
4665 optimization. On the second pass twiddle tls_mask flags to
4666 notify relocate_section that optimization can be done, and
4667 adjust got and plt refcounts. */
4670 {
4677 {
4681 /* Read the relocations. */
4689 {
4695 bfd_boolean is_local;
4700 {
4708 }
4716 /* If this section has old-style __tls_get_addr calls
4717 without marker relocs, then check that each
4718 __tls_get_addr call reloc is preceded by a reloc
4719 that conceivably belongs to the __tls_get_addr arg
4720 setup insn. If we don't find matching arg setup
4721 relocs, don't do any tls optimization. */
4726 && !expecting_tls_get_addr
4728 {
4735 }
4739 {
4743 /* Fall thru */
4747 /* These relocs should never be against a symbol
4748 defined in a shared lib. Leave them alone if
4749 that turns out to be the case. */
4753 /* LD -> LE */
4761 /* Fall thru */
4766 /* GD -> LE */
4768 else
4769 /* GD -> IE */
4779 {
4780 /* IE -> LE */
4784 }
4785 else
4797 }
4800 {
4811 /* Uh oh, we didn't find the expected call. We
4812 could just mark this symbol to exclude it
4813 from tls optimization but it's safer to skip
4814 the entire optimization. */
4821 }
4824 {
4838 }
4841 {
4844 }
4845 else
4846 {
4852 {
4859 {
4863 }
4864 }
4873 }
4876 {
4877 /* We managed to get rid of a got entry. */
4880 }
4884 }
4888 }
4892 {
4895 else
4897 }
4898 }
4900 }
4901 \f
4902 /* Return true if we have dynamic relocs that apply to read-only sections. */
4904 static bfd_boolean
4906 {
4910 {
4917 }
4919 }
4921 /* Adjust a symbol defined by a dynamic object and referenced by a
4922 regular object. The current definition is in some section of the
4923 dynamic object, but we're not including those sections. We have to
4924 change the definition to something the rest of the link can
4925 understand. */
4927 static bfd_boolean
4930 {
4934 #ifdef DEBUG
4937 #endif
4939 /* Make sure we know what is going on here. */
4949 /* Deal with function syms. */
4953 {
4954 /* Clear procedure linkage table information for any symbol that
4955 won't need a .plt entry. */
4965 {
4966 /* A PLT entry is not required/allowed when:
4968 1. We are not using ld.so; because then the PLT entry
4969 can't be set up, so we can't use one. In this case,
4970 ppc_elf_adjust_dynamic_symbol won't even be called.
4972 2. GC has rendered the entry unused.
4974 3. We know for certain that a call to this symbol
4975 will go to this object, or will remain undefined. */
4978 }
4979 else
4980 {
4981 /* After adjust_dynamic_symbol, non_got_ref set in the
4982 non-shared case means that we have allocated space in
4983 .dynbss for the symbol and thus dyn_relocs for this
4984 symbol should be discarded.
4985 If we get here we know we are making a PLT entry for this
4986 symbol, and in an executable we'd normally resolve
4987 relocations against this symbol to the PLT entry. Allow
4988 dynamic relocs if the reference is weak, and the dynamic
4989 relocs will not cause text relocation. */
4997 }
4999 }
5000 else
5003 /* If this is a weak symbol, and there is a real definition, the
5004 processor independent code will have arranged for us to see the
5005 real definition first, and we can just use the same value. */
5007 {
5015 }
5017 /* This is a reference to a symbol defined by a dynamic object which
5018 is not a function. */
5020 /* If we are creating a shared library, we must presume that the
5021 only references to the symbol are via the global offset table.
5022 For such cases we need not do anything here; the relocations will
5023 be handled correctly by relocate_section. */
5027 /* If there are no references to this symbol that do not use the
5028 GOT, we don't need to generate a copy reloc. */
5032 /* If we didn't find any dynamic relocs in read-only sections, then
5033 we'll be keeping the dynamic relocs and avoiding the copy reloc.
5034 We can't do this if there are any small data relocations. This
5035 doesn't work on VxWorks, where we can not have dynamic
5036 relocations (other than copy and jump slot relocations) in an
5037 executable. */
5043 {
5046 }
5049 {
5053 }
5055 /* We must allocate the symbol in our .dynbss section, which will
5056 become part of the .bss section of the executable. There will be
5057 an entry for this symbol in the .dynsym section. The dynamic
5058 object will contain position independent code, so all references
5059 from the dynamic object to this symbol will go through the global
5060 offset table. The dynamic linker will use the .dynsym entry to
5061 determine the address it must put in the global offset table, so
5062 both the dynamic object and the regular object will refer to the
5063 same memory location for the variable.
5065 Of course, if the symbol is referenced using SDAREL relocs, we
5066 must instead allocate it in .sbss. */
5070 else
5074 /* We must generate a R_PPC_COPY reloc to tell the dynamic linker to
5075 copy the initial value out of the dynamic object and into the
5076 runtime process image. We need to remember the offset into the
5077 .rela.bss section we are going to use. */
5079 {
5084 else
5089 }
5092 }
5093 \f
5094 /* Generate a symbol to mark plt call stubs. For non-PIC code the sym is
5095 xxxxxxxx.plt_call32.<callee> where xxxxxxxx is a hex number, usually 0,
5096 specifying the addend on the plt relocation. For -fpic code, the sym
5097 is xxxxxxxx.plt_pic32.<callee>, and for -fPIC
5098 xxxxxxxx.got2.plt_pic32.<callee>. */
5100 static bfd_boolean
5104 {
5113 else
5133 {
5142 }
5144 }
5146 /* Allocate NEED contiguous space in .got, and return the offset.
5147 Handles allocation of the got header when crossing 32k. */
5149 static bfd_vma
5151 {
5152 bfd_vma where;
5156 {
5159 }
5160 else
5161 {
5164 {
5167 }
5168 else
5169 {
5172 {
5175 }
5178 }
5179 }
5181 }
5183 /* Allocate space in associated reloc sections for dynamic relocs. */
5185 static bfd_boolean
5187 {
5199 {
5203 bfd_boolean dyn;
5207 {
5208 /* Make sure this symbol is output as a dynamic symbol. */
5213 {
5216 }
5222 {
5228 {
5230 {
5233 }
5238 {
5244 }
5249 {
5252 }
5258 }
5259 else
5260 {
5262 {
5263 /* If this is the first .plt entry, make room
5264 for the special first entry. */
5268 /* The PowerPC PLT is actually composed of two
5269 parts, the first part is 2 words (for a load
5270 and a jump), and then there is a remaining
5271 word available at the end. */
5278 /* If this symbol is not defined in a regular
5279 file, and we are not generating a shared
5280 library, then set the symbol to this location
5281 in the .plt. This is to avoid text
5282 relocations, and is required to make
5283 function pointers compare as equal between
5284 the normal executable and the shared library. */
5288 {
5291 }
5293 /* Make room for this entry. */
5295 /* After the 8192nd entry, room for two entries
5296 is allocated. */
5302 }
5304 }
5306 /* We also need to make an entry in the .rela.plt section. */
5308 {
5312 else
5313 {
5317 {
5318 /* Allocate space for the unloaded relocations. */
5321 {
5324 {
5328 }
5333 }
5335 /* Every PLT entry has an associated GOT entry in
5336 .got.plt. */
5338 }
5339 }
5341 }
5342 }
5343 else
5345 }
5346 else
5350 {
5353 }
5354 }
5355 else
5356 {
5359 }
5363 {
5364 bfd_boolean dyn;
5367 /* Make sure this symbol is output as a dynamic symbol. */
5372 {
5375 }
5379 {
5381 {
5383 /* We'll just use htab->tlsld_got.offset. This should
5384 always be the case. It's a little odd if we have
5385 a local dynamic reloc against a non-local symbol. */
5387 else
5389 }
5396 }
5397 else
5401 else
5402 {
5409 {
5411 /* All the entries we allocated need relocs.
5412 Except LD only needs one. */
5417 }
5418 }
5419 }
5420 else
5427 /* In the shared -Bsymbolic case, discard space allocated for
5428 dynamic pc-relative relocs against symbols which turn out to be
5429 defined in regular objects. For the normal shared case, discard
5430 space for relocs that have become local due to symbol visibility
5431 changes. */
5434 {
5435 /* Relocs that use pc_count are those that appear on a call insn,
5436 or certain REL relocs (see must_be_dyn_reloc) that can be
5437 generated via assembly. We want calls to protected symbols to
5438 resolve directly to the function rather than going via the plt.
5439 If people want function pointer comparisons to work as expected
5440 then they should avoid writing weird assembly. */
5442 {
5446 {
5451 else
5453 }
5454 }
5457 {
5461 {
5464 else
5466 }
5467 }
5469 /* Discard relocs on undefined symbols that must be local. */
5476 /* Also discard relocs on undefined weak syms with non-default
5477 visibility. */
5480 {
5484 /* Make sure undefined weak symbols are output as a dynamic
5485 symbol in PIEs. */
5489 {
5492 }
5493 }
5494 }
5496 {
5497 /* For the non-shared case, discard space for relocs against
5498 symbols which turn out to need copy relocs or are not
5499 dynamic. */
5503 {
5504 /* Make sure this symbol is output as a dynamic symbol.
5505 Undefined weak syms won't yet be marked as dynamic. */
5508 {
5511 }
5513 /* If that succeeded, we know we'll be keeping all the
5514 relocs. */
5517 }
5521 keep: ;
5522 }
5524 /* Finally, allocate space. */
5526 {
5531 }
5534 }
5536 /* Set DF_TEXTREL if we find any dynamic relocs that apply to
5537 read-only sections. */
5539 static bfd_boolean
5541 {
5546 {
5549 /* Not an error, just cut short the traversal. */
5551 }
5553 }
5556 {
5567 };
5569 /* Set the sizes of the dynamic sections. */
5571 static bfd_boolean
5574 {
5577 bfd_boolean relocs;
5580 #ifdef DEBUG
5582 #endif
5588 {
5589 /* Set the contents of the .interp section to the interpreter. */
5591 {
5596 }
5597 }
5604 /* Set up .got offsets for local syms, and space for local dynamic
5605 relocs. */
5607 {
5613 bfd_size_type locsymcount;
5620 {
5627 {
5630 {
5631 /* Input section has been discarded, either because
5632 it is a copy of a linkonce section or due to
5633 linker script /DISCARD/, so we'll be discarding
5634 the relocs too. */
5635 }
5639 {
5640 /* Relocations in vxworks .tls_vars sections are
5641 handled specially by the loader. */
5642 }
5644 {
5653 }
5654 }
5655 }
5670 {
5673 {
5682 }
5683 else
5687 else
5688 {
5693 }
5694 }
5695 else
5701 /* Allocate space for calls to local STT_GNU_IFUNC syms in .iplt. */
5703 {
5710 {
5714 {
5717 }
5722 {
5725 }
5729 {
5732 }
5733 }
5734 else
5736 }
5737 }
5739 /* Allocate space for global sym dynamic relocs. */
5743 {
5747 }
5748 else
5752 {
5755 /* If we haven't allocated the header, do so now. When we get here,
5756 for old plt/got the got size will be 0 to 32764 (not allocated),
5757 or 32780 to 65536 (header allocated). For new plt/got, the
5758 corresponding ranges are 0 to 32768 and 32780 to 65536. */
5760 {
5765 }
5768 }
5770 {
5775 {
5779 }
5780 }
5785 {
5787 /* Space for the branch table. */
5789 /* Pad out to align the start of PLTresolve. */
5794 {
5801 {
5810 }
5816 {
5825 }
5826 }
5827 }
5833 {
5837 {
5841 }
5842 }
5844 /* We've now determined the sizes of the various dynamic sections.
5845 Allocate memory for them. */
5848 {
5856 {
5857 /* We'd like to strip these sections if they aren't needed, but if
5858 we've exported dynamic symbols from them we must leave them.
5859 It's too late to tell BFD to get rid of the symbols. */
5862 /* Strip this section if we don't need it; see the
5863 comment below. */
5864 }
5874 {
5875 /* Strip these too. */
5876 }
5878 {
5880 {
5881 /* Remember whether there are any relocation sections. */
5884 /* We use the reloc_count field as a counter if we need
5885 to copy relocs into the output file. */
5887 }
5888 }
5889 else
5890 {
5891 /* It's not one of our sections, so don't allocate space. */
5893 }
5896 {
5897 /* If we don't need this section, strip it from the
5898 output file. This is mostly to handle .rela.bss and
5899 .rela.plt. We must create both sections in
5900 create_dynamic_sections, because they must be created
5901 before the linker maps input sections to output
5902 sections. The linker does that before
5903 adjust_dynamic_symbol is called, and it is that
5904 function which decides whether anything needs to go
5905 into these sections. */
5908 }
5913 /* Allocate memory for the section contents. */
5917 }
5920 {
5921 /* Add some entries to the .dynamic section. We fill in the
5922 values later, in ppc_elf_finish_dynamic_sections, but we
5923 must add the entries now so that we get the correct size for
5924 the .dynamic section. The DT_DEBUG entry is filled in by the
5925 dynamic linker and used by the debugger. */
5926 #define add_dynamic_entry(TAG, VAL) \
5927 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
5930 {
5933 }
5936 {
5942 }
5945 {
5953 }
5956 {
5961 }
5963 /* If any dynamic relocs apply to a read-only section, then we
5964 need a DT_TEXTREL entry. */
5967 info);
5970 {
5973 }
5977 }
5978 #undef add_dynamic_entry
5981 }
5983 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
5985 static bfd_boolean
5987 {
5995 }
5996 \f
5997 #define ARRAY_SIZE(a) (sizeof (a) / sizeof ((a)[0]))
5999 /* Relaxation trampolines. r12 is available for clobbering (r11, is
6000 used for some functions that are allowed to break the ABI). */
6002 {
6011 };
6014 {
6019 };
6021 static bfd_boolean
6026 {
6027 struct one_fixup
6028 {
6031 /* Final link, can use the symbol offset. For a
6032 relocatable link we use the symbol's index. */
6033 bfd_vma toff;
6034 bfd_vma trampoff;
6035 };
6045 bfd_size_type trampoff;
6047 bfd_boolean maybe_pasted;
6051 /* Nothing to do if there are no relocations, and no need to do
6052 anything with non-alloc or non-code sections. */
6059 /* We cannot represent the required PIC relocs in the output, so don't
6060 do anything. The linker doesn't support mixing -shared and -r
6061 anyway. */
6068 /* Space for a branch around any trampolines. */
6074 /* Get a copy of the native relocations. */
6085 {
6099 {
6114 }
6116 /* Get the value of the symbol referred to by the reloc. */
6119 {
6120 /* A local symbol. */
6123 /* Read this BFD's local symbols. */
6125 {
6133 }
6141 else
6146 }
6147 else
6148 {
6149 /* Global symbol handling. */
6161 {
6164 }
6167 {
6170 }
6171 else
6175 }
6177 /* The condition here under which we call find_plt_ent must
6178 match that in relocate_section. If we call find_plt_ent here
6179 but not in relocate_section, or vice versa, then the branch
6180 destination used here may be incorrect. */
6183 {
6184 /* We know is_branch_reloc (r_type) is true. */
6188 }
6191 {
6196 }
6198 {
6206 {
6211 {
6214 }
6215 else
6216 {
6219 }
6220 }
6221 }
6223 /* If the branch and target are in the same section, you have
6224 no hope of adding stubs. We'll error out later should the
6225 branch overflow. */
6229 /* There probably isn't any reason to handle symbols in
6230 SEC_MERGE sections; SEC_MERGE doesn't seem a likely
6231 attribute for a code section, and we are only looking at
6232 branches. However, implement it correctly here as a
6233 reference for other target relax_section functions. */
6235 {
6236 /* At this stage in linking, no SEC_MERGE symbol has been
6237 adjusted, so all references to such symbols need to be
6238 passed through _bfd_merged_section_offset. (Later, in
6239 relocate_section, all SEC_MERGE symbols *except* for
6240 section symbols have been adjusted.)
6242 gas may reduce relocations against symbols in SEC_MERGE
6243 sections to a relocation against the section symbol when
6244 the original addend was zero. When the reloc is against
6245 a section symbol we should include the addend in the
6246 offset passed to _bfd_merged_section_offset, since the
6247 location of interest is the original symbol. On the
6248 other hand, an access to "sym+addend" where "sym" is not
6249 a section symbol should not include the addend; Such an
6250 access is presumed to be an offset from "sym"; The
6251 location of interest is just "sym". */
6257 toff);
6261 }
6262 /* PLTREL24 addends are special. */
6266 /* Attempted -shared link of non-pic code loses. */
6272 /* If the branch is in range, no need to do anything. */
6275 /* A relocatable link may have sections moved during
6276 final link, so do not presume they remain in range. */
6278 {
6285 }
6287 /* Look for an existing fixup to this address. */
6293 {
6299 /* Oh dear, we can't reach a trampoline. Don't try to add
6300 one. We'll report an error later. */
6304 {
6307 }
6308 else
6309 {
6312 }
6316 {
6320 }
6322 /* Hijack the old relocation. Since we need two
6323 relocations for this use a "composite" reloc. */
6325 stub_rtype);
6331 /* Record the fixup so we don't do it again this section. */
6340 changes++;
6341 }
6342 else
6343 {
6348 /* Nop out the reloc, since we're finalizing things here. */
6350 }
6352 /* Get the section contents. */
6354 {
6355 /* Get cached copy if it exists. */
6358 else
6359 {
6360 /* Go get them off disk. */
6363 }
6364 }
6366 /* Fix up the existing branch to hit the trampoline. */
6369 {
6387 }
6388 }
6390 /* Write out the trampolines. */
6392 {
6397 do
6398 {
6402 }
6411 /* Branch around the trampolines. */
6413 {
6417 }
6421 {
6424 }
6425 else
6426 {
6429 }
6433 {
6435 i++;
6439 }
6441 }
6445 {
6448 else
6449 {
6450 /* Cache the symbols for elf_link_input_bfd. */
6452 }
6453 }
6457 {
6460 else
6461 {
6462 /* Cache the section contents for elf_link_input_bfd. */
6464 }
6465 }
6468 {
6469 /* Append sufficient NOP relocs so we can write out relocation
6470 information for the trampolines. */
6481 {
6485 }
6492 }
6498 {
6499 /* Convert the internal relax relocs to external form. */
6502 {
6505 /* Rewrite the reloc and convert one of the trailing nop
6506 relocs to describe this relocation. */
6508 /* The relocs are at the bottom 2 bytes */
6514 irel++;
6515 }
6516 }
6520 error_return:
6530 }
6531 \f
6532 /* What to do when ld finds relocations against symbols defined in
6533 discarded sections. */
6535 static unsigned int
6537 {
6545 }
6546 \f
6547 /* Fill in the address for a pointer generated in a linker section. */
6549 static bfd_vma
6553 bfd_vma relocation,
6555 {
6561 {
6562 /* Handle global symbol. */
6568 }
6569 else
6570 {
6571 /* Handle local symbol. */
6577 }
6581 lsect);
6584 /* Offset will always be a multiple of four, so use the bottom bit
6585 as a "written" flag. */
6587 {
6592 }
6599 #ifdef DEBUG
6603 #endif
6606 }
6608 #define PPC_LO(v) ((v) & 0xffff)
6609 #define PPC_HI(v) (((v) >> 16) & 0xffff)
6610 #define PPC_HA(v) PPC_HI ((v) + 0x8000)
6612 static void
6615 {
6618 bfd_vma plt;
6625 {
6638 {
6647 }
6648 else
6649 {
6658 }
6659 }
6660 else
6661 {
6670 }
6671 }
6673 /* Return true if symbol is defined statically. */
6675 static bfd_boolean
6677 {
6682 }
6684 /* If INSN is an opcode that may be used with an @tls operand, return
6685 the transformed insn for TLS optimisation, otherwise return 0. If
6686 REG is non-zero only match an insn with RB or RA equal to REG. */
6688 unsigned int
6690 {
6700 else
6704 /* add -> addi. */
6710 /* load and store indexed -> dform. */
6713 /* ldx, ldux, stdx, stdux -> ld, ldu, std, stdu. */
6716 /* lwax -> lwa. */
6718 else
6722 }
6724 /* If INSN is an opcode that may be used with an @tprel operand, return
6725 the transformed insn for an undefined weak symbol, ie. with the
6726 thread pointer REG operand removed. Otherwise return 0. */
6728 unsigned int
6730 {
6751 {
6753 }
6758 {
6763 }
6764 else
6767 }
6769 /* The RELOCATE_SECTION function is called by the ELF backend linker
6770 to handle the relocations for a section.
6772 The relocs are always passed as Rela structures; if the section
6773 actually uses Rel structures, the r_addend field will always be
6774 zero.
6776 This function is responsible for adjust the section contents as
6777 necessary, and (if using Rela relocs and generating a
6778 relocatable output file) adjusting the reloc addend as
6779 necessary.
6781 This function does not have to worry about setting the reloc
6782 address or the reloc symbol index.
6784 LOCAL_SYMS is a pointer to the swapped in local symbols.
6786 LOCAL_SECTIONS is an array giving the section in the input file
6787 corresponding to the st_shndx field of each local symbol.
6789 The global hash table entry for the global symbols can be found
6790 via elf_sym_hashes (input_bfd).
6792 When generating relocatable output, this function must handle
6793 STB_LOCAL/STT_SECTION symbols specially. The output symbol is
6794 going to be the section symbol corresponding to the output
6795 section, which means that the addend must be adjusted
6796 accordingly. */
6798 static bfd_boolean
6807 {
6813 Elf_Internal_Rela outrel;
6818 bfd_boolean is_vxworks_tls;
6820 #ifdef DEBUG
6826 #endif
6830 /* Initialize howto table if not already done. */
6838 /* We have to handle relocations in vxworks .tls_vars sections
6839 specially, because the dynamic loader is 'weird'. */
6846 {
6848 bfd_vma addend;
6849 bfd_reloc_status_type r;
6856 bfd_vma relocation;
6858 bfd_boolean unresolved_reloc;
6859 bfd_boolean warned;
6872 {
6878 }
6879 else
6880 {
6887 }
6890 {
6891 /* For relocs against symbols from removed linkonce sections,
6892 or sections discarded by a linker script, we just want the
6893 section contents zeroed. Avoid any special processing. */
6899 }
6902 {
6906 {
6907 /* R_PPC_PLTREL24 is rather special. If non-zero, the
6908 addend specifies the GOT pointer offset within .got2. */
6910 }
6912 }
6914 /* TLS optimizations. Replace instruction sequences and relocs
6915 based on information we collected in tls_optimize. We edit
6916 RELOCS so that --emit-relocs will output something sensible
6917 for the final instruction stream. */
6923 {
6926 local_plt
6930 }
6932 /* Ensure reloc mapping code below stays sane. */
6943 {
6951 {
6952 bfd_vma insn;
6960 }
6966 {
6967 bfd_vma insn;
6977 /* Was PPC_TLS which sits on insn boundary, now
6978 PPC_TPREL16_LO which is at low-order half-word. */
6980 }
6993 {
6994 tls_gdld_hi:
6998 else
6999 {
7003 }
7005 }
7018 {
7020 bfd_vma offset;
7022 tls_ldgd_opt:
7024 /* If not using the newer R_PPC_TLSGD/LD to mark
7025 __tls_get_addr calls, we must trust that the call
7026 stays with its arg setup insns, ie. that the next
7027 reloc is the __tls_get_addr call associated with
7028 the current reloc. Edit both insns. */
7035 {
7036 /* IE */
7042 {
7046 }
7050 }
7051 else
7052 {
7053 /* LE */
7056 {
7057 /* Was an LD reloc. */
7060 r_symndx++)
7070 }
7074 {
7080 }
7081 }
7085 {
7086 /* We changed the symbol on an LD reloc. Start over
7087 in order to get h, sym, sec etc. right. */
7088 rel--;
7090 }
7091 }
7096 {
7101 {
7102 /* IE */
7105 }
7106 else
7107 {
7108 /* LE */
7112 }
7115 /* Zap the reloc on the _tls_get_addr call too. */
7118 }
7123 {
7128 r_symndx++)
7144 /* Zap the reloc on the _tls_get_addr call too. */
7147 rel--;
7149 }
7151 }
7153 /* Handle other relocations that tweak non-addend part of insn. */
7156 {
7160 /* Branch taken prediction relocations. */
7164 /* Fall thru */
7166 /* Branch not taken prediction relocations. */
7169 {
7170 bfd_vma insn;
7180 /* Invert 'y' bit if not the default. */
7186 }
7187 }
7191 {
7195 {
7198 }
7201 {
7207 }
7213 {
7218 }
7220 {
7222 {
7223 Elf_Internal_Rela rela;
7237 }
7239 {
7244 }
7253 else
7257 }
7258 }
7266 {
7285 /* GOT16 relocations. Like an ADDR16 using the symbol's
7286 address in the GOT as relocation value instead of the
7287 symbol's value itself. Also, create a GOT entry for the
7288 symbol and put the symbol value there. */
7322 dogot:
7323 {
7324 /* Relocation is to the entry for this symbol in the global
7325 offset table. */
7326 bfd_vma off;
7339 {
7340 bfd_boolean dyn;
7345 /* This is actually a static link, or it is a
7346 -Bsymbolic link and the symbol is defined
7347 locally, or the symbol was forced to be local
7348 because of a version file. */
7349 ;
7350 else
7351 {
7354 }
7356 }
7357 else
7358 {
7362 }
7364 /* The offset must always be a multiple of 4. We use the
7365 least significant bit to record whether we have already
7366 processed this entry. */
7370 else
7371 {
7382 /* We might have multiple got entries for this sym.
7383 Initialize them all. */
7384 do
7385 {
7389 {
7392 }
7394 {
7397 }
7399 {
7402 }
7404 {
7407 }
7409 /* Generate relocs for the dynamic linker. */
7415 {
7424 {
7427 {
7434 outrel.r_info
7436 }
7437 }
7446 else
7449 {
7453 }
7458 }
7460 /* Init the .got section contents if we're not
7461 emitting a reloc. */
7462 else
7463 {
7469 {
7475 {
7479 }
7480 }
7483 }
7488 }
7493 }
7499 {
7501 {
7507 {
7511 {
7514 }
7515 }
7516 }
7517 }
7521 + off
7524 /* Addends on got relocations don't make much sense.
7525 x+off@got is actually x@got+off, and since the got is
7526 generated by a hash table traversal, the value in the
7527 got at entry m+n bears little relation to the entry m. */
7533 sym_name);
7534 }
7537 /* Relocations that need no special processing. */
7539 /* It makes no sense to point a local relocation
7540 at a symbol not in this object. */
7542 {
7545 input_bfd,
7546 input_section,
7548 TRUE))
7551 }
7561 /* Relocations that may need to be propagated if this is a shared
7562 object. */
7570 {
7571 /* Make this relocation against an undefined weak symbol
7572 resolve to zero. This is really just a tweak, since
7573 code using weak externs ought to check that they are
7574 defined before using them. */
7581 }
7583 /* The TPREL16 relocs shouldn't really be used in shared
7584 libs as they will result in DT_TEXTREL being set, but
7585 support them anyway. */
7610 /* fall through */
7625 /* If these relocations are not to a named symbol, they can be
7626 handled right here, no need to bother the dynamic linker. */
7630 /* fall through */
7638 /* fall through */
7640 dodyn:
7654 || (ELIMINATE_COPY_RELOCS
7660 {
7663 #ifdef DEBUG
7668 #endif
7670 /* When generating a shared object, these relocations
7671 are copied into the output file to be resolved at run
7672 time. */
7674 {
7680 }
7684 input_section,
7698 {
7702 }
7703 else
7704 {
7708 {
7712 {
7713 /* If we get here when building a static
7714 executable, then the libc startup function
7715 responsible for applying indirect function
7716 relocations is going to complain about
7717 the reloc type.
7718 If we get here when building a dynamic
7719 executable, it will be because we have
7720 a text relocation. The dynamic loader
7721 will set the text segment writable and
7722 non-executable to apply text relocations.
7723 So we'll segfault when trying to run the
7724 indirection function to resolve the reloc. */
7730 sym_name);
7732 }
7734 ;
7736 {
7739 }
7740 else
7741 {
7744 /* We are turning this relocation into one
7745 against a section symbol. It would be
7746 proper to subtract the symbol's value,
7747 osec->vma, from the emitted reloc addend,
7748 but ld.so expects buggy relocs.
7749 FIXME: Why not always use a zero index? */
7753 {
7756 }
7758 #ifdef DEBUG
7763 #endif
7764 }
7767 }
7770 else
7772 }
7781 /* This reloc will be computed at runtime. We clear the memory
7782 so that it contains predictable value. */
7786 {
7790 }
7791 }
7797 {
7802 {
7806 }
7812 else
7816 }
7817 /* Fall thru */
7825 {
7832 /* We're clearing the bits for R_PPC_ADDR16_HA
7833 and R_PPC_ADDR16_LO here. */
7837 /* t0 is HA, t1 is LO */
7845 /* Rewrite the reloc and convert one of the trailing nop
7846 relocs to describe this relocation. */
7848 /* The relocs are at the bottom 2 bytes */
7854 rel++;
7855 }
7858 /* Indirect .sdata relocation. */
7862 {
7865 }
7866 relocation
7872 /* Indirect .sdata2 relocation. */
7876 {
7879 }
7880 relocation
7886 /* Handle the TOC16 reloc. We want to use the offset within the .got
7887 section, not the actual VMA. This is appropriate when generating
7888 an embedded ELF object, for which the .got section acts like the
7889 AIX .toc section. */
7892 {
7895 }
7905 /* Relocation is to the entry for this symbol in the
7906 procedure linkage table. */
7907 {
7913 {
7914 /* We didn't make a PLT entry for this symbol. This
7915 happens when statically linking PIC code, or when
7916 using -Bsymbolic. */
7918 }
7925 else
7929 }
7932 /* Relocate against _SDA_BASE_. */
7934 {
7941 {
7944 }
7952 {
7956 input_bfd,
7957 sym_name,
7959 name);
7960 }
7961 }
7964 /* Relocate against _SDA2_BASE_. */
7966 {
7973 {
7976 }
7982 {
7986 input_bfd,
7987 sym_name,
7989 name);
7990 }
7991 }
7994 /* Relocate against either _SDA_BASE_, _SDA2_BASE_, or 0. */
7997 {
8003 {
8006 }
8013 {
8016 }
8019 {
8022 }
8025 {
8027 }
8028 else
8029 {
8033 input_bfd,
8034 sym_name,
8036 name);
8041 }
8044 {
8046 {
8049 }
8051 }
8054 {
8060 }
8061 }
8064 /* Relocate against the beginning of the section. */
8070 {
8073 }
8077 /* Negative relocations. */
8104 input_bfd,
8106 sym_name);
8111 }
8113 /* Do any further special processing. */
8115 {
8126 /* It's just possible that this symbol is a weak symbol
8127 that's not actually defined anywhere. In that case,
8128 'sec' would be NULL, and we should leave the symbol
8129 alone (it will be set to zero elsewhere in the link). */
8132 /* Fall thru */
8140 /* Add 0x10000 if sign bit in 0:15 is set.
8141 Bits 0:15 are not used. */
8144 }
8146 #ifdef DEBUG
8151 sym_name,
8152 r_symndx,
8155 #endif
8162 {
8167 sym_name);
8169 }
8172 input_bfd,
8173 input_section,
8174 contents,
8176 relocation,
8177 addend);
8180 {
8182 {
8188 {
8189 /* Assume this is a call protected by other code that
8190 detect the symbol is undefined. If this is the case,
8191 we can safely ignore the overflow. If not, the
8192 program is hosed anyway, and a little warning isn't
8193 going to help. */
8196 }
8200 sym_name,
8203 input_bfd,
8204 input_section,
8207 }
8208 else
8209 {
8215 }
8216 }
8217 }
8219 #ifdef DEBUG
8221 #endif
8224 }
8225 \f
8226 /* Finish up dynamic symbol handling. We set the contents of various
8227 dynamic sections here. */
8229 static bfd_boolean
8234 {
8237 bfd_boolean doneone;
8239 #ifdef DEBUG
8242 #endif
8250 {
8252 {
8253 Elf_Internal_Rela rela;
8255 bfd_vma reloc_index;
8261 else
8262 {
8268 }
8270 /* This symbol has an entry in the procedure linkage table.
8271 Set it up. */
8275 {
8276 bfd_vma got_offset;
8279 /* The first three entries in .got.plt are reserved. */
8282 /* Use the right PLT. */
8286 /* Fill in the .plt on VxWorks. */
8288 {
8295 }
8296 else
8297 {
8306 }
8313 /* This instruction is an immediate load. The value loaded is
8314 the byte offset of the R_PPC_JMP_SLOT relocation from the
8315 start of the .rela.plt section. The value is stored in the
8316 low-order 16 bits of the load instruction. */
8317 /* NOTE: It appears that this is now an index rather than a
8318 prescaled offset. */
8322 /* This instruction is a PC-relative branch whose target is
8323 the start of the PLT section. The address of this branch
8324 instruction is 20 bytes beyond the start of this PLT entry.
8325 The address is encoded in bits 6-29, inclusive. The value
8326 stored is right-shifted by two bits, permitting a 26-bit
8327 offset. */
8337 /* Fill in the GOT entry corresponding to this PLT slot with
8338 the address immediately after the the "bctr" instruction
8339 in this PLT entry. */
8346 {
8347 /* Fill in a couple of entries in .rela.plt.unloaded. */
8353 /* Provide the @ha relocation for the first instruction. */
8358 R_PPC_ADDR16_HA);
8363 /* Provide the @l relocation for the second instruction. */
8368 R_PPC_ADDR16_LO);
8373 /* Provide a relocation for the GOT entry corresponding to this
8374 PLT slot. Point it at the middle of the .plt entry. */
8379 R_PPC_ADDR32);
8382 }
8384 /* VxWorks uses non-standard semantics for R_PPC_JMP_SLOT.
8385 In particular, the offset for the relocation is not the
8386 address of the PLT entry for this function, as specified
8387 by the ABI. Instead, the offset is set to the address of
8388 the GOT slot for this function. See EABI 4.4.4.1. */
8393 }
8394 else
8395 {
8407 {
8408 /* We don't need to fill in the .plt. The ppc dynamic
8409 linker will fill it in. */
8410 }
8411 else
8412 {
8418 }
8419 }
8421 /* Fill in the entry in the .rela.plt section. */
8425 {
8432 }
8433 else
8441 else
8447 {
8448 /* Mark the symbol as undefined, rather than as
8449 defined in the .plt section. Leave the value if
8450 there were any relocations where pointer equality
8451 matters (this is a clue for the dynamic linker, to
8452 make function pointer comparisons work between an
8453 application and shared library), otherwise set it
8454 to zero. */
8459 {
8460 /* This breaks function pointer comparisons, but
8461 that is better than breaking tests for a NULL
8462 function pointer. */
8464 }
8465 }
8468 {
8469 /* Set the value of ifunc symbols in a non-pie
8470 executable to the glink entry. This is to avoid
8471 text relocations. We can't do this for ifunc in
8472 allocate_dynrelocs, as we do for normal dynamic
8473 function symbols with plt entries, because we need
8474 to keep the original value around for the ifunc
8475 relocation. */
8481 }
8483 }
8488 {
8498 {
8515 }
8520 /* We only need one non-PIC glink stub. */
8522 }
8523 else
8525 }
8528 {
8530 Elf_Internal_Rela rela;
8533 /* This symbols needs a copy reloc. Set it up. */
8535 #ifdef DEBUG
8537 #endif
8543 else
8552 }
8554 #ifdef DEBUG
8556 #endif
8558 /* Mark some specially defined symbols as absolute. */
8567 }
8568 \f
8569 static enum elf_reloc_type_class
8571 {
8573 {
8584 }
8585 }
8586 \f
8587 /* Finish up the dynamic sections. */
8589 static bfd_boolean
8592 {
8596 bfd_vma got;
8600 #ifdef DEBUG
8602 #endif
8609 else
8617 {
8625 {
8626 Elf_Internal_Dyn dyn;
8632 {
8636 else
8656 {
8660 }
8668 }
8671 }
8672 }
8675 {
8678 {
8683 {
8684 /* Add a blrl instruction at _GLOBAL_OFFSET_TABLE_-4
8685 so that a function can easily find the address of
8686 _GLOBAL_OFFSET_TABLE_. */
8690 }
8693 {
8698 }
8699 }
8700 else
8701 {
8708 }
8711 }
8713 /* Fill in the first entry in the VxWorks procedure linkage table. */
8715 {
8716 /* Use the right PLT. */
8718 ? ppc_elf_vxworks_pic_plt0_entry
8722 {
8729 }
8730 else
8731 {
8734 }
8743 {
8744 Elf_Internal_Rela rela;
8749 /* Output the @ha relocation for the first instruction. */
8758 /* Output the @l relocation for the second instruction. */
8767 /* Fix up the remaining relocations. They may have the wrong
8768 symbol index for _G_O_T_ or _P_L_T_ depending on the order
8769 in which symbols were output. */
8771 {
8772 Elf_Internal_Rela rel;
8788 }
8789 }
8790 }
8795 {
8798 bfd_vma res0;
8801 /*
8802 * PIC glink code is the following:
8803 *
8804 * # ith PLT code stub.
8805 * addis 11,30,(plt+(i-1)*4-got)@ha
8806 * lwz 11,(plt+(i-1)*4-got)@l(11)
8807 * mtctr 11
8808 * bctr
8809 *
8810 * # A table of branches, one for each plt entry.
8811 * # The idea is that the plt call stub loads ctr and r11 with these
8812 * # addresses, so (r11 - res_0) gives the plt index * 4.
8813 * res_0: b PLTresolve
8814 * res_1: b PLTresolve
8815 * .
8816 * # Some number of entries towards the end can be nops
8817 * res_n_m3: nop
8818 * res_n_m2: nop
8819 * res_n_m1:
8820 *
8821 * PLTresolve:
8822 * addis 11,11,(1f-res_0)@ha
8823 * mflr 0
8824 * bcl 20,31,1f
8825 * 1: addi 11,11,(1b-res_0)@l
8826 * mflr 12
8827 * mtlr 0
8828 * sub 11,11,12 # r11 = index * 4
8829 * addis 12,12,(got+4-1b)@ha
8830 * lwz 0,(got+4-1b)@l(12) # got[1] address of dl_runtime_resolve
8831 * lwz 12,(got+8-1b)@l(12) # got[2] contains the map address
8832 * mtctr 0
8833 * add 0,11,11
8834 * add 11,0,11 # r11 = index * 12 = reloc offset.
8835 * bctr
8836 */
8838 {
8839 ADDIS_11_11,
8840 MFLR_0,
8841 BCL_20_31,
8842 ADDI_11_11,
8843 MFLR_12,
8844 MTLR_0,
8845 SUB_11_11_12,
8846 ADDIS_12_12,
8847 LWZ_0_12,
8848 LWZ_12_12,
8849 MTCTR_0,
8850 ADD_0_11_11,
8851 ADD_11_0_11,
8852 BCTR,
8853 NOP,
8854 NOP
8855 };
8857 /*
8858 * Non-PIC glink code is a little simpler.
8859 *
8860 * # ith PLT code stub.
8861 * lis 11,(plt+(i-1)*4)@ha
8862 * lwz 11,(plt+(i-1)*4)@l(11)
8863 * mtctr 11
8864 * bctr
8865 *
8866 * The branch table is the same, then comes
8867 *
8868 * PLTresolve:
8869 * lis 12,(got+4)@ha
8870 * addis 11,11,(-res_0)@ha
8871 * lwz 0,(got+4)@l(12) # got[1] address of dl_runtime_resolve
8872 * addi 11,11,(-res_0)@l # r11 = index * 4
8873 * mtctr 0
8874 * add 0,11,11
8875 * lwz 12,(got+8)@l(12) # got[2] contains the map address
8876 * add 11,0,11 # r11 = index * 12 = reloc offset.
8877 * bctr
8878 */
8880 {
8881 LIS_12,
8882 ADDIS_11_11,
8883 LWZ_0_12,
8884 ADDI_11_11,
8885 MTCTR_0,
8886 ADD_0_11_11,
8887 LWZ_12_12,
8888 ADD_11_0_11,
8889 BCTR,
8890 NOP,
8891 NOP,
8892 NOP,
8893 NOP,
8894 NOP,
8895 NOP,
8896 NOP
8897 };
8904 /* Build the branch table, one for each plt entry (less one),
8905 and perhaps some padding. */
8911 {
8914 }
8916 {
8919 }
8925 /* Last comes the PLTresolve stub. */
8927 {
8928 bfd_vma bcl;
8931 {
8934 }
8948 {
8953 }
8954 else
8955 {
8960 }
8961 }
8962 else
8963 {
8965 {
8968 }
8978 {
8983 }
8984 else
8985 {
8990 }
8991 }
8992 }
8996 {
8998 bfd_vma val;
9001 /* CIE length (rewrite in case little-endian). */
9004 /* FDE length. */
9008 /* CIE pointer. */
9012 /* Offset to .glink. */
9020 /* .glink size. */
9023 /* Augmentation. */
9028 {
9033 {
9036 }
9038 {
9042 }
9043 else
9044 {
9048 }
9051 p++;
9055 }
9064 }
9067 }
9068 \f
9069 #define TARGET_LITTLE_SYM bfd_elf32_powerpcle_vec
9071 #define TARGET_BIG_SYM bfd_elf32_powerpc_vec
9073 #define ELF_ARCH bfd_arch_powerpc
9074 #define ELF_TARGET_ID PPC32_ELF_DATA
9075 #define ELF_MACHINE_CODE EM_PPC
9076 #ifdef __QNXTARGET__
9077 #define ELF_MAXPAGESIZE 0x1000
9078 #else
9079 #define ELF_MAXPAGESIZE 0x10000
9080 #endif
9081 #define ELF_MINPAGESIZE 0x1000
9082 #define ELF_COMMONPAGESIZE 0x1000
9083 #define elf_info_to_howto ppc_elf_info_to_howto
9085 #ifdef EM_CYGNUS_POWERPC
9086 #define ELF_MACHINE_ALT1 EM_CYGNUS_POWERPC
9087 #endif
9089 #ifdef EM_PPC_OLD
9090 #define ELF_MACHINE_ALT2 EM_PPC_OLD
9091 #endif
9093 #define elf_backend_plt_not_loaded 1
9094 #define elf_backend_can_gc_sections 1
9095 #define elf_backend_can_refcount 1
9096 #define elf_backend_rela_normal 1
9098 #define bfd_elf32_mkobject ppc_elf_mkobject
9099 #define bfd_elf32_bfd_merge_private_bfd_data ppc_elf_merge_private_bfd_data
9100 #define bfd_elf32_bfd_relax_section ppc_elf_relax_section
9101 #define bfd_elf32_bfd_reloc_type_lookup ppc_elf_reloc_type_lookup
9102 #define bfd_elf32_bfd_reloc_name_lookup ppc_elf_reloc_name_lookup
9103 #define bfd_elf32_bfd_set_private_flags ppc_elf_set_private_flags
9104 #define bfd_elf32_bfd_link_hash_table_create ppc_elf_link_hash_table_create
9105 #define bfd_elf32_get_synthetic_symtab ppc_elf_get_synthetic_symtab
9107 #define elf_backend_object_p ppc_elf_object_p
9108 #define elf_backend_gc_mark_hook ppc_elf_gc_mark_hook
9109 #define elf_backend_gc_sweep_hook ppc_elf_gc_sweep_hook
9110 #define elf_backend_section_from_shdr ppc_elf_section_from_shdr
9111 #define elf_backend_relocate_section ppc_elf_relocate_section
9112 #define elf_backend_create_dynamic_sections ppc_elf_create_dynamic_sections
9113 #define elf_backend_check_relocs ppc_elf_check_relocs
9114 #define elf_backend_copy_indirect_symbol ppc_elf_copy_indirect_symbol
9115 #define elf_backend_adjust_dynamic_symbol ppc_elf_adjust_dynamic_symbol
9116 #define elf_backend_add_symbol_hook ppc_elf_add_symbol_hook
9117 #define elf_backend_size_dynamic_sections ppc_elf_size_dynamic_sections
9118 #define elf_backend_hash_symbol ppc_elf_hash_symbol
9119 #define elf_backend_finish_dynamic_symbol ppc_elf_finish_dynamic_symbol
9120 #define elf_backend_finish_dynamic_sections ppc_elf_finish_dynamic_sections
9121 #define elf_backend_fake_sections ppc_elf_fake_sections
9122 #define elf_backend_additional_program_headers ppc_elf_additional_program_headers
9123 #define elf_backend_grok_prstatus ppc_elf_grok_prstatus
9124 #define elf_backend_grok_psinfo ppc_elf_grok_psinfo
9125 #define elf_backend_write_core_note ppc_elf_write_core_note
9126 #define elf_backend_reloc_type_class ppc_elf_reloc_type_class
9127 #define elf_backend_begin_write_processing ppc_elf_begin_write_processing
9128 #define elf_backend_final_write_processing ppc_elf_final_write_processing
9129 #define elf_backend_write_section ppc_elf_write_section
9130 #define elf_backend_get_sec_type_attr ppc_elf_get_sec_type_attr
9131 #define elf_backend_plt_sym_val ppc_elf_plt_sym_val
9132 #define elf_backend_action_discarded ppc_elf_action_discarded
9133 #define elf_backend_init_index_section _bfd_elf_init_1_index_section
9134 #define elf_backend_post_process_headers _bfd_elf_set_osabi
9138 /* FreeBSD Target */
9140 #undef TARGET_LITTLE_SYM
9141 #undef TARGET_LITTLE_NAME
9143 #undef TARGET_BIG_SYM
9144 #define TARGET_BIG_SYM bfd_elf32_powerpc_freebsd_vec
9145 #undef TARGET_BIG_NAME
9148 #undef ELF_OSABI
9149 #define ELF_OSABI ELFOSABI_FREEBSD
9151 #undef elf32_bed
9152 #define elf32_bed elf32_powerpc_fbsd_bed
9156 /* VxWorks Target */
9158 #undef TARGET_LITTLE_SYM
9159 #undef TARGET_LITTLE_NAME
9161 #undef TARGET_BIG_SYM
9162 #define TARGET_BIG_SYM bfd_elf32_powerpc_vxworks_vec
9163 #undef TARGET_BIG_NAME
9166 #undef ELF_OSABI
9168 /* VxWorks uses the elf default section flags for .plt. */
9171 {
9179 }
9181 /* Like ppc_elf_link_hash_table_create, but overrides
9182 appropriately for VxWorks. */
9185 {
9190 {
9198 }
9200 }
9202 /* Tweak magic VxWorks symbols as they are loaded. */
9203 static bfd_boolean
9211 {
9213 valp))
9217 }
9219 static void
9221 {
9224 }
9226 /* On VxWorks, we emit relocations against _PROCEDURE_LINKAGE_TABLE_, so
9227 define it. */
9228 #undef elf_backend_want_plt_sym
9229 #define elf_backend_want_plt_sym 1
9230 #undef elf_backend_want_got_plt
9231 #define elf_backend_want_got_plt 1
9232 #undef elf_backend_got_symbol_offset
9233 #define elf_backend_got_symbol_offset 0
9234 #undef elf_backend_plt_not_loaded
9235 #define elf_backend_plt_not_loaded 0
9236 #undef elf_backend_plt_readonly
9237 #define elf_backend_plt_readonly 1
9238 #undef elf_backend_got_header_size
9239 #define elf_backend_got_header_size 12
9241 #undef bfd_elf32_get_synthetic_symtab
9243 #undef bfd_elf32_bfd_link_hash_table_create
9244 #define bfd_elf32_bfd_link_hash_table_create \
9245 ppc_elf_vxworks_link_hash_table_create
9246 #undef elf_backend_add_symbol_hook
9247 #define elf_backend_add_symbol_hook \
9248 ppc_elf_vxworks_add_symbol_hook
9249 #undef elf_backend_link_output_symbol_hook
9250 #define elf_backend_link_output_symbol_hook \
9251 elf_vxworks_link_output_symbol_hook
9252 #undef elf_backend_final_write_processing
9253 #define elf_backend_final_write_processing \
9254 ppc_elf_vxworks_final_write_processing
9255 #undef elf_backend_get_sec_type_attr
9256 #define elf_backend_get_sec_type_attr \
9257 ppc_elf_vxworks_get_sec_type_attr
9258 #undef elf_backend_emit_relocs
9259 #define elf_backend_emit_relocs \
9260 elf_vxworks_emit_relocs
9262 #undef elf32_bed
9263 #define elf32_bed ppc_elf_vxworks_bed
9264 #undef elf_backend_post_process_headers