sysdeps/alpha/dl-machine.h

   1 /* Machine-dependent ELF dynamic relocation inline functions.  Alpha version.
   2    Copyright (C) 1996-2002, 2003, 2004 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Richard Henderson <rth@tamu.edu>.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library 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 GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 /* This was written in the absence of an ABI -- don't expect
  22    it to remain unchanged.  */
  23
  24 #ifndef dl_machine_h
  25 #define dl_machine_h 1
  26
  27 #define ELF_MACHINE_NAME "alpha"
  28
  29 #include <string.h>
  30
  31
  32 /* Mask identifying addresses reserved for the user program,
  33    where the dynamic linker should not map anything.  */
  34 #define ELF_MACHINE_USER_ADDRESS_MASK   0x120000000UL
  35
  36 /* Return nonzero iff ELF header is compatible with the running host.  */
  37 static inline int
  38 elf_machine_matches_host (const Elf64_Ehdr *ehdr)
  39 {
  40   return ehdr->e_machine == EM_ALPHA;
  41 }
  42
  43 /* Return the link-time address of _DYNAMIC.  The multiple-got-capable
  44    linker no longer allocates the first .got entry for this.  But not to
  45    worry, no special tricks are needed.  */
  46 static inline Elf64_Addr
  47 elf_machine_dynamic (void)
  48 {
  49 #ifndef NO_AXP_MULTI_GOT_LD
  50   return (Elf64_Addr) &_DYNAMIC;
  51 #else
  52   register Elf64_Addr *gp __asm__ ("$29");
  53   return gp[-4096];
  54 #endif
  55 }
  56
  57 /* Return the run-time load address of the shared object.  */
  58 static inline Elf64_Addr
  59 elf_machine_load_address (void)
  60 {
  61   /* NOTE: While it is generally unfriendly to put data in the text
  62      segment, it is only slightly less so when the "data" is an
  63      instruction.  While we don't have to worry about GLD just yet, an
  64      optimizing linker might decide that our "data" is an unreachable
  65      instruction and throw it away -- with the right switches, DEC's
  66      linker will do this.  What ought to happen is we should add
  67      something to GAS to allow us access to the new GPREL_HI32/LO32
  68      relocation types stolen from OSF/1 3.0.  */
  69   /* This code relies on the fact that BRADDR relocations do not
  70      appear in dynamic relocation tables.  Not that that would be very
  71      useful anyway -- br/bsr has a 4MB range and the shared libraries
  72      are usually many many terabytes away.  */
  73
  74   Elf64_Addr dot;
  75   long int zero_disp;
  76
  77   asm("br %0, 1f\n"
  78       "0:\n\t"
  79       "br $0, 2f\n"
  80       "1:\n\t"
  81       ".section\t.data\n"
  82       "2:\n\t"
  83       ".quad 0b\n\t"
  84       ".previous"
  85       : "=r"(dot));
  86
  87   zero_disp = *(int *) dot;
  88   zero_disp = (zero_disp << 43) >> 41;
  89
  90   return dot - *(Elf64_Addr *) (dot + 4 + zero_disp);
  91 }
  92
  93 /* Set up the loaded object described by L so its unrelocated PLT
  94    entries will jump to the on-demand fixup code in dl-runtime.c.  */
  95
  96 static inline int
  97 elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
  98 {
  99   Elf64_Addr plt;
 100   extern void _dl_runtime_resolve (void);
 101   extern void _dl_runtime_profile (void);
 102
 103   if (l->l_info[DT_JMPREL] && lazy)
 104     {
 105       /* The GOT entries for the functions in the PLT have not been
 106          filled in yet.  Their initial contents are directed to the
 107          PLT which arranges for the dynamic linker to be called.  */
 108       plt = D_PTR (l, l_info[DT_PLTGOT]);
 109
 110       /* This function will be called to perform the relocation.  */
 111       if (!profile)
 112         *(Elf64_Addr *)(plt + 16) = (Elf64_Addr) &_dl_runtime_resolve;
 113       else
 114         {
 115           *(Elf64_Addr *)(plt + 16) = (Elf64_Addr) &_dl_runtime_profile;
 116
 117           if (_dl_name_match_p (GLRO(dl_profile), l))
 118             {
 119               /* This is the object we are looking for.  Say that we really
 120                  want profiling and the timers are started.  */
 121               GL(dl_profile_map) = l;
 122             }
 123         }
 124
 125       /* Identify this shared object */
 126       *(Elf64_Addr *)(plt + 24) = (Elf64_Addr) l;
 127
 128       /* If the first instruction of the plt entry is not
 129          "br $28, plt0", we have to reinitialize .plt for lazy relocation.  */
 130       if (*(unsigned int *)(plt + 32) != 0xc39ffff7)
 131         {
 132           unsigned int val = 0xc39ffff7;
 133           unsigned int *slot, *end;
 134           const Elf64_Rela *rela = (const Elf64_Rela *)
 135                                    D_PTR (l, l_info[DT_JMPREL]);
 136           Elf64_Addr l_addr = l->l_addr;
 137
 138           /* br t12,.+4; ldq t12,12(t12); nop; jmp t12,(t12),.+4 */
 139           *(unsigned long *)plt = 0xa77b000cc3600000;
 140           *(unsigned long *)(plt + 8) = 0x6b7b000047ff041f;
 141           slot = (unsigned int *)(plt + 32);
 142           end = (unsigned int *)(plt + 32
 143                                  + l->l_info[DT_PLTRELSZ]->d_un.d_val / 2);
 144           while (slot < end)
 145             {
 146               /* br at,.plt+0 */
 147               *slot = val;
 148               *(Elf64_Addr *) rela->r_offset = (Elf64_Addr) slot - l_addr;
 149               val -= 3;
 150               slot += 3;
 151               ++rela;
 152             }
 153         }
 154     }
 155
 156   return lazy;
 157 }
 158
 159 /* This code is used in dl-runtime.c to call the `fixup' function
 160    and then redirect to the address it returns.  */
 161 #define TRAMPOLINE_TEMPLATE(tramp_name, fixup_name, IMB)        \
 162   extern void tramp_name (void);                                \
 163   asm ( "\
 164         .globl " #tramp_name "                                  \n\
 165         .ent " #tramp_name "                                    \n\
 166 " #tramp_name ":                                                \n\
 167         lda     $sp, -44*8($sp)                                 \n\
 168         .frame  $sp, 44*8, $26                                  \n\
 169         /* Preserve all integer registers that C normally       \n\
 170            doesn't.  */                                         \n\
 171         stq     $26, 0*8($sp)                                   \n\
 172         stq     $0, 1*8($sp)                                    \n\
 173         stq     $1, 2*8($sp)                                    \n\
 174         stq     $2, 3*8($sp)                                    \n\
 175         stq     $3, 4*8($sp)                                    \n\
 176         stq     $4, 5*8($sp)                                    \n\
 177         stq     $5, 6*8($sp)                                    \n\
 178         stq     $6, 7*8($sp)                                    \n\
 179         stq     $7, 8*8($sp)                                    \n\
 180         stq     $8, 9*8($sp)                                    \n\
 181         stq     $16, 10*8($sp)                                  \n\
 182         stq     $17, 11*8($sp)                                  \n\
 183         stq     $18, 12*8($sp)                                  \n\
 184         stq     $19, 13*8($sp)                                  \n\
 185         stq     $20, 14*8($sp)                                  \n\
 186         stq     $21, 15*8($sp)                                  \n\
 187         stq     $22, 16*8($sp)                                  \n\
 188         stq     $23, 17*8($sp)                                  \n\
 189         stq     $24, 18*8($sp)                                  \n\
 190         stq     $25, 19*8($sp)                                  \n\
 191         stq     $29, 20*8($sp)                                  \n\
 192         stt     $f0, 21*8($sp)                                  \n\
 193         stt     $f1, 22*8($sp)                                  \n\
 194         stt     $f10, 23*8($sp)                                 \n\
 195         stt     $f11, 24*8($sp)                                 \n\
 196         stt     $f12, 25*8($sp)                                 \n\
 197         stt     $f13, 26*8($sp)                                 \n\
 198         stt     $f14, 27*8($sp)                                 \n\
 199         stt     $f15, 28*8($sp)                                 \n\
 200         stt     $f16, 29*8($sp)                                 \n\
 201         stt     $f17, 30*8($sp)                                 \n\
 202         stt     $f18, 31*8($sp)                                 \n\
 203         stt     $f19, 32*8($sp)                                 \n\
 204         stt     $f20, 33*8($sp)                                 \n\
 205         stt     $f21, 34*8($sp)                                 \n\
 206         stt     $f22, 35*8($sp)                                 \n\
 207         stt     $f23, 36*8($sp)                                 \n\
 208         stt     $f24, 37*8($sp)                                 \n\
 209         stt     $f25, 38*8($sp)                                 \n\
 210         stt     $f26, 39*8($sp)                                 \n\
 211         stt     $f27, 40*8($sp)                                 \n\
 212         stt     $f28, 41*8($sp)                                 \n\
 213         stt     $f29, 42*8($sp)                                 \n\
 214         stt     $f30, 43*8($sp)                                 \n\
 215         .mask   0x27ff01ff, -44*8                               \n\
 216         .fmask  0xfffffc03, -(44-21)*8                          \n\
 217         /* Set up our $gp */                                    \n\
 218         br      $gp, .+4                                        \n\
 219         ldgp    $gp, 0($gp)                                     \n\
 220         .prologue 0                                             \n\
 221         /* Set up the arguments for fixup: */                   \n\
 222         /* $16 = link_map out of plt0 */                        \n\
 223         /* $17 = offset of reloc entry = ($28 - $27 - 20) /12 * 24 */\n\
 224         /* $18 = return address */                              \n\
 225         subq    $28, $27, $17                                   \n\
 226         ldq     $16, 8($27)                                     \n\
 227         subq    $17, 20, $17                                    \n\
 228         mov     $26, $18                                        \n\
 229         addq    $17, $17, $17                                   \n\
 230         /* Do the fixup */                                      \n\
 231         bsr     $26, " #fixup_name "    !samegp                 \n\
 232         /* Move the destination address into position.  */      \n\
 233         mov     $0, $27                                         \n\
 234         /* Restore program registers.  */                       \n\
 235         ldq     $26, 0*8($sp)                                   \n\
 236         ldq     $0, 1*8($sp)                                    \n\
 237         ldq     $1, 2*8($sp)                                    \n\
 238         ldq     $2, 3*8($sp)                                    \n\
 239         ldq     $3, 4*8($sp)                                    \n\
 240         ldq     $4, 5*8($sp)                                    \n\
 241         ldq     $5, 6*8($sp)                                    \n\
 242         ldq     $6, 7*8($sp)                                    \n\
 243         ldq     $7, 8*8($sp)                                    \n\
 244         ldq     $8, 9*8($sp)                                    \n\
 245         ldq     $16, 10*8($sp)                                  \n\
 246         ldq     $17, 11*8($sp)                                  \n\
 247         ldq     $18, 12*8($sp)                                  \n\
 248         ldq     $19, 13*8($sp)                                  \n\
 249         ldq     $20, 14*8($sp)                                  \n\
 250         ldq     $21, 15*8($sp)                                  \n\
 251         ldq     $22, 16*8($sp)                                  \n\
 252         ldq     $23, 17*8($sp)                                  \n\
 253         ldq     $24, 18*8($sp)                                  \n\
 254         ldq     $25, 19*8($sp)                                  \n\
 255         ldq     $29, 20*8($sp)                                  \n\
 256         ldt     $f0, 21*8($sp)                                  \n\
 257         ldt     $f1, 22*8($sp)                                  \n\
 258         ldt     $f10, 23*8($sp)                                 \n\
 259         ldt     $f11, 24*8($sp)                                 \n\
 260         ldt     $f12, 25*8($sp)                                 \n\
 261         ldt     $f13, 26*8($sp)                                 \n\
 262         ldt     $f14, 27*8($sp)                                 \n\
 263         ldt     $f15, 28*8($sp)                                 \n\
 264         ldt     $f16, 29*8($sp)                                 \n\
 265         ldt     $f17, 30*8($sp)                                 \n\
 266         ldt     $f18, 31*8($sp)                                 \n\
 267         ldt     $f19, 32*8($sp)                                 \n\
 268         ldt     $f20, 33*8($sp)                                 \n\
 269         ldt     $f21, 34*8($sp)                                 \n\
 270         ldt     $f22, 35*8($sp)                                 \n\
 271         ldt     $f23, 36*8($sp)                                 \n\
 272         ldt     $f24, 37*8($sp)                                 \n\
 273         ldt     $f25, 38*8($sp)                                 \n\
 274         ldt     $f26, 39*8($sp)                                 \n\
 275         ldt     $f27, 40*8($sp)                                 \n\
 276         ldt     $f28, 41*8($sp)                                 \n\
 277         ldt     $f29, 42*8($sp)                                 \n\
 278         ldt     $f30, 43*8($sp)                                 \n\
 279         /* Flush the Icache after having modified the .plt code.  */\n\
 280         " #IMB "                                                \n\
 281         /* Clean up and turn control to the destination */      \n\
 282         lda     $sp, 44*8($sp)                                  \n\
 283         jmp     $31, ($27)                                      \n\
 284         .end " #tramp_name)
 285
 286 #ifndef PROF
 287 #define ELF_MACHINE_RUNTIME_TRAMPOLINE                          \
 288   TRAMPOLINE_TEMPLATE (_dl_runtime_resolve, fixup, imb);        \
 289   TRAMPOLINE_TEMPLATE (_dl_runtime_profile, profile_fixup, /* nop */);
 290 #else
 291 #define ELF_MACHINE_RUNTIME_TRAMPOLINE                          \
 292   TRAMPOLINE_TEMPLATE (_dl_runtime_resolve, fixup, imb);        \
 293   strong_alias (_dl_runtime_resolve, _dl_runtime_profile);
 294 #endif
 295
 296 /* Initial entry point code for the dynamic linker.
 297    The C function `_dl_start' is the real entry point;
 298    its return value is the user program's entry point.  */
 299
 300 #define RTLD_START asm ("\
 301         .section .text                                          \n\
 302         .set at                                                 \n\
 303         .globl _start                                           \n\
 304         .ent _start                                             \n\
 305 _start:                                                         \n\
 306         .frame $31,0,$31,0                                      \n\
 307         br      $gp, 0f                                         \n\
 308 0:      ldgp    $gp, 0($gp)                                     \n\
 309         .prologue 0                                             \n\
 310         /* Pass pointer to argument block to _dl_start.  */     \n\
 311         mov     $sp, $16                                        \n\
 312         bsr     $26, _dl_start          !samegp                 \n\
 313         .end _start                                             \n\
 314         /* FALLTHRU */                                          \n\
 315         .globl _dl_start_user                                   \n\
 316         .ent _dl_start_user                                     \n\
 317 _dl_start_user:                                                 \n\
 318         .frame $31,0,$31,0                                      \n\
 319         .prologue 0                                             \n\
 320         /* Save the user entry point address in s0.  */         \n\
 321         mov     $0, $9                                          \n\
 322         /* See if we were run as a command with the executable  \n\
 323            file name as an extra leading argument.  */          \n\
 324         ldah    $1, _dl_skip_args($gp)  !gprelhigh              \n\
 325         ldl     $1, _dl_skip_args($1)   !gprellow               \n\
 326         bne     $1, $fixup_stack                                \n\
 327 $fixup_stack_ret:                                               \n\
 328         /* The special initializer gets called with the stack   \n\
 329            just as the application's entry point will see it;   \n\
 330            it can switch stacks if it moves these contents      \n\
 331            over.  */                                            \n\
 332 " RTLD_START_SPECIAL_INIT "                                     \n\
 333         /* Call _dl_init(_dl_loaded, argc, argv, envp) to run   \n\
 334            initializers.  */                                    \n\
 335         ldah    $16, _rtld_local($gp)   !gprelhigh              \n\
 336         ldq     $16, _rtld_local($16)   !gprellow               \n\
 337         ldq     $17, 0($sp)                                     \n\
 338         lda     $18, 8($sp)                                     \n\
 339         s8addq  $17, 8, $19                                     \n\
 340         addq    $19, $18, $19                                   \n\
 341         bsr     $26, _dl_init_internal  !samegp                 \n\
 342         /* Pass our finalizer function to the user in $0. */    \n\
 343         ldah    $0, _dl_fini($gp)       !gprelhigh              \n\
 344         lda     $0, _dl_fini($0)        !gprellow               \n\
 345         /* Jump to the user's entry point.  */                  \n\
 346         mov     $9, $27                                         \n\
 347         jmp     ($9)                                            \n\
 348 $fixup_stack:                                                   \n\
 349         /* Adjust the stack pointer to skip _dl_skip_args words.\n\
 350            This involves copying everything down, since the     \n\
 351            stack pointer must always be 16-byte aligned.  */    \n\
 352         ldah    $7, _dl_argv_internal($gp) !gprelhigh           \n\
 353         ldq     $2, 0($sp)                                      \n\
 354         ldq     $5, _dl_argv_internal($7) !gprellow             \n\
 355         subq    $31, $1, $6                                     \n\
 356         subq    $2, $1, $2                                      \n\
 357         s8addq  $6, $5, $5                                      \n\
 358         mov     $sp, $4                                         \n\
 359         s8addq  $1, $sp, $3                                     \n\
 360         stq     $2, 0($sp)                                      \n\
 361         stq     $5, _dl_argv_internal($7) !gprellow             \n\
 362         /* Copy down argv.  */                                  \n\
 363 0:      ldq     $5, 8($3)                                       \n\
 364         addq    $4, 8, $4                                       \n\
 365         addq    $3, 8, $3                                       \n\
 366         stq     $5, 0($4)                                       \n\
 367         bne     $5, 0b                                          \n\
 368         /* Copy down envp.  */                                  \n\
 369 1:      ldq     $5, 8($3)                                       \n\
 370         addq    $4, 8, $4                                       \n\
 371         addq    $3, 8, $3                                       \n\
 372         stq     $5, 0($4)                                       \n\
 373         bne     $5, 1b                                          \n\
 374         /* Copy down auxiliary table.  */                       \n\
 375 2:      ldq     $5, 8($3)                                       \n\
 376         ldq     $6, 16($3)                                      \n\
 377         addq    $4, 16, $4                                      \n\
 378         addq    $3, 16, $3                                      \n\
 379         stq     $5, -8($4)                                      \n\
 380         stq     $6, 0($4)                                       \n\
 381         bne     $5, 2b                                          \n\
 382         br      $fixup_stack_ret                                \n\
 383         .end _dl_start_user                                     \n\
 384         .set noat                                               \n\
 385 .previous");
 386
 387 #ifndef RTLD_START_SPECIAL_INIT
 388 #define RTLD_START_SPECIAL_INIT /* nothing */
 389 #endif
 390
 391 /* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry
 392    or TLS variables, so undefined references should not be allowed
 393    to define the value.
 394
 395    ELF_RTYPE_CLASS_NOCOPY iff TYPE should not be allowed to resolve
 396    to one of the main executable's symbols, as for a COPY reloc.
 397    This is unused on Alpha.  */
 398
 399 #if defined USE_TLS && (!defined RTLD_BOOTSTRAP || USE___THREAD)
 400 #define elf_machine_type_class(type)    \
 401   (((type) == R_ALPHA_JMP_SLOT          \
 402     || (type) == R_ALPHA_DTPMOD64       \
 403     || (type) == R_ALPHA_DTPREL64       \
 404     || (type) == R_ALPHA_TPREL64) * ELF_RTYPE_CLASS_PLT)
 405 #else
 406 #define elf_machine_type_class(type)    \
 407   (((type) == R_ALPHA_JMP_SLOT) * ELF_RTYPE_CLASS_PLT)
 408 #endif
 409
 410 /* A reloc type used for ld.so cmdline arg lookups to reject PLT entries.  */
 411 #define ELF_MACHINE_JMP_SLOT     R_ALPHA_JMP_SLOT
 412
 413 /* The alpha never uses Elf64_Rel relocations.  */
 414 #define ELF_MACHINE_NO_REL 1
 415
 416 /* Fix up the instructions of a PLT entry to invoke the function
 417    rather than the dynamic linker.  */
 418 static inline Elf64_Addr
 419 elf_machine_fixup_plt (struct link_map *l, lookup_t t,
 420                        const Elf64_Rela *reloc,
 421                        Elf64_Addr *got_addr, Elf64_Addr value)
 422 {
 423   const Elf64_Rela *rela_plt;
 424   Elf64_Word *plte;
 425   long int edisp;
 426
 427   /* Store the value we are going to load.  */
 428   *got_addr = value;
 429
 430   /* Recover the PLT entry address by calculating reloc's index into the
 431      .rela.plt, and finding that entry in the .plt.  */
 432   rela_plt = (void *) D_PTR (l, l_info[DT_JMPREL]);
 433   plte = (void *) (D_PTR (l, l_info[DT_PLTGOT]) + 32);
 434   plte += 3 * (reloc - rela_plt);
 435
 436   /* Find the displacement from the plt entry to the function.  */
 437   edisp = (long int) (value - (Elf64_Addr)&plte[3]) / 4;
 438
 439   if (edisp >= -0x100000 && edisp < 0x100000)
 440     {
 441       /* If we are in range, use br to perfect branch prediction and
 442          elide the dependency on the address load.  This case happens,
 443          e.g., when a shared library call is resolved to the same library.  */
 444
 445       int hi, lo;
 446       hi = value - (Elf64_Addr)&plte[0];
 447       lo = (short int) hi;
 448       hi = (hi - lo) >> 16;
 449
 450       /* Emit "lda $27,lo($27)" */
 451       plte[1] = 0x237b0000 | (lo & 0xffff);
 452
 453       /* Emit "br $31,function" */
 454       plte[2] = 0xc3e00000 | (edisp & 0x1fffff);
 455
 456       /* Think about thread-safety -- the previous instructions must be
 457          committed to memory before the first is overwritten.  */
 458       __asm__ __volatile__("wmb" : : : "memory");
 459
 460       /* Emit "ldah $27,hi($27)" */
 461       plte[0] = 0x277b0000 | (hi & 0xffff);
 462     }
 463   else
 464     {
 465       /* Don't bother with the hint since we already know the hint is
 466          wrong.  Eliding it prevents the wrong page from getting pulled
 467          into the cache.  */
 468
 469       int hi, lo;
 470       hi = (Elf64_Addr)got_addr - (Elf64_Addr)&plte[0];
 471       lo = (short)hi;
 472       hi = (hi - lo) >> 16;
 473
 474       /* Emit "ldq $27,lo($27)" */
 475       plte[1] = 0xa77b0000 | (lo & 0xffff);
 476
 477       /* Emit "jmp $31,($27)" */
 478       plte[2] = 0x6bfb0000;
 479
 480       /* Think about thread-safety -- the previous instructions must be
 481          committed to memory before the first is overwritten.  */
 482       __asm__ __volatile__("wmb" : : : "memory");
 483
 484       /* Emit "ldah $27,hi($27)" */
 485       plte[0] = 0x277b0000 | (hi & 0xffff);
 486     }
 487
 488   /* At this point, if we've been doing runtime resolution, Icache is dirty.
 489      This will be taken care of in _dl_runtime_resolve.  If instead we are
 490      doing this as part of non-lazy startup relocation, that bit of code
 491      hasn't made it into Icache yet, so there's nothing to clean up.  */
 492
 493   return value;
 494 }
 495
 496 /* Return the final value of a plt relocation.  */
 497 static inline Elf64_Addr
 498 elf_machine_plt_value (struct link_map *map, const Elf64_Rela *reloc,
 499                        Elf64_Addr value)
 500 {
 501   return value + reloc->r_addend;
 502 }
 503
 504 #endif /* !dl_machine_h */
 505
 506 #ifdef RESOLVE
 507
 508 /* Perform the relocation specified by RELOC and SYM (which is fully resolved).
 509    MAP is the object containing the reloc.  */
 510 auto inline void
 511 elf_machine_rela (struct link_map *map,
 512                   const Elf64_Rela *reloc,
 513                   const Elf64_Sym *sym,
 514                   const struct r_found_version *version,
 515                   void *const reloc_addr_arg)
 516 {
 517   Elf64_Addr *const reloc_addr = reloc_addr_arg;
 518   unsigned long int const r_type = ELF64_R_TYPE (reloc->r_info);
 519
 520 #if !defined RTLD_BOOTSTRAP && !defined HAVE_Z_COMBRELOC && !defined SHARED
 521   /* This is defined in rtld.c, but nowhere in the static libc.a; make the
 522      reference weak so static programs can still link.  This declaration
 523      cannot be done when compiling rtld.c (i.e.  #ifdef RTLD_BOOTSTRAP)
 524      because rtld.c contains the common defn for _dl_rtld_map, which is
 525      incompatible with a weak decl in the same file.  */
 526   weak_extern (_dl_rtld_map);
 527 #endif
 528
 529   /* We cannot use a switch here because we cannot locate the switch
 530      jump table until we've self-relocated.  */
 531
 532 #if !defined RTLD_BOOTSTRAP || !defined HAVE_Z_COMBRELOC
 533   if (__builtin_expect (r_type == R_ALPHA_RELATIVE, 0))
 534     {
 535 # if !defined RTLD_BOOTSTRAP && !defined HAVE_Z_COMBRELOC
 536       /* Already done in dynamic linker.  */
 537       if (map != &GL(dl_rtld_map))
 538 # endif
 539         {
 540           /* XXX Make some timings.  Maybe it's preferable to test for
 541              unaligned access and only do it the complex way if necessary.  */
 542           Elf64_Addr reloc_addr_val;
 543
 544           /* Load value without causing unaligned trap. */
 545           memcpy (&reloc_addr_val, reloc_addr_arg, 8);
 546           reloc_addr_val += map->l_addr;
 547
 548           /* Store value without causing unaligned trap. */
 549           memcpy (reloc_addr_arg, &reloc_addr_val, 8);
 550         }
 551     }
 552   else
 553 #endif
 554     if (__builtin_expect (r_type == R_ALPHA_NONE, 0))
 555       return;
 556   else
 557     {
 558       Elf64_Addr sym_value;
 559       Elf64_Addr sym_raw_value;
 560
 561 #if defined USE_TLS && !defined RTLD_BOOTSTRAP
 562       struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type);
 563       sym_raw_value = sym_value = reloc->r_addend;
 564       if (sym)
 565         {
 566           sym_raw_value += sym->st_value;
 567           sym_value = sym_raw_value + sym_map->l_addr;
 568         }
 569 #else
 570       Elf64_Addr loadbase = RESOLVE (&sym, version, r_type);
 571       sym_raw_value = sym_value = reloc->r_addend;
 572       if (sym)
 573         {
 574           sym_raw_value += sym->st_value;
 575           sym_value = sym_raw_value + loadbase;
 576         }
 577 #endif
 578
 579       if (r_type == R_ALPHA_GLOB_DAT)
 580         *reloc_addr = sym_value;
 581 #ifdef RESOLVE_CONFLICT_FIND_MAP
 582       /* In .gnu.conflict section, R_ALPHA_JMP_SLOT relocations have
 583          R_ALPHA_JMP_SLOT in lower 8 bits and the remaining 24 bits
 584          are .rela.plt index.  */
 585       else if ((r_type & 0xff) == R_ALPHA_JMP_SLOT)
 586         {
 587           /* elf_machine_fixup_plt needs the map reloc_addr points into,
 588              while in _dl_resolve_conflicts map is _dl_loaded.  */
 589           RESOLVE_CONFLICT_FIND_MAP (map, reloc_addr);
 590           reloc = ((const Elf64_Rela *) D_PTR (map, l_info[DT_JMPREL]))
 591                   + (r_type >> 8);
 592           elf_machine_fixup_plt (map, 0, reloc, reloc_addr, sym_value);
 593         }
 594 #else
 595       else if (r_type == R_ALPHA_JMP_SLOT)
 596         elf_machine_fixup_plt (map, 0, reloc, reloc_addr, sym_value);
 597 #endif
 598 #ifndef RTLD_BOOTSTRAP
 599       else if (r_type == R_ALPHA_REFQUAD)
 600         {
 601           /* Store value without causing unaligned trap.  */
 602           memcpy (reloc_addr_arg, &sym_value, 8);
 603         }
 604 #endif
 605 #if defined USE_TLS && (!defined RTLD_BOOTSTRAP || USE___THREAD)
 606       else if (r_type == R_ALPHA_DTPMOD64)
 607         {
 608 #ifdef RTLD_BOOTSTRAP
 609           /* During startup the dynamic linker is always index 1.  */
 610           *reloc_addr = 1;
 611 #else
 612           /* Get the information from the link map returned by the
 613              resolv function.  */
 614           if (sym_map != NULL)
 615             *reloc_addr = sym_map->l_tls_modid;
 616 #endif
 617         }
 618       else if (r_type == R_ALPHA_DTPREL64)
 619         {
 620 #ifndef RTLD_BOOTSTRAP
 621           /* During relocation all TLS symbols are defined and used.
 622              Therefore the offset is already correct.  */
 623           *reloc_addr = sym_raw_value;
 624 #endif
 625         }
 626       else if (r_type == R_ALPHA_TPREL64)
 627         {
 628 #ifdef RTLD_BOOTSTRAP
 629           *reloc_addr = sym_raw_value + map->l_tls_offset;
 630 #else
 631           if (sym_map)
 632             {
 633               CHECK_STATIC_TLS (map, sym_map);
 634               *reloc_addr = sym_raw_value + sym_map->l_tls_offset;
 635             }
 636 #endif
 637         }
 638 #endif /* USE_TLS */
 639       else
 640         _dl_reloc_bad_type (map, r_type, 0);
 641     }
 642 }
 643
 644 /* Let do-rel.h know that on Alpha if l_addr is 0, all RELATIVE relocs
 645    can be skipped.  */
 646 #define ELF_MACHINE_REL_RELATIVE 1
 647
 648 auto inline void
 649 elf_machine_rela_relative (Elf64_Addr l_addr, const Elf64_Rela *reloc,
 650                            void *const reloc_addr_arg)
 651 {
 652   /* XXX Make some timings.  Maybe it's preferable to test for
 653      unaligned access and only do it the complex way if necessary.  */
 654   Elf64_Addr reloc_addr_val;
 655
 656   /* Load value without causing unaligned trap. */
 657   memcpy (&reloc_addr_val, reloc_addr_arg, 8);
 658   reloc_addr_val += l_addr;
 659
 660   /* Store value without causing unaligned trap. */
 661   memcpy (reloc_addr_arg, &reloc_addr_val, 8);
 662 }
 663
 664 auto inline void
 665 elf_machine_lazy_rel (struct link_map *map,
 666                       Elf64_Addr l_addr, const Elf64_Rela *reloc)
 667 {
 668   Elf64_Addr * const reloc_addr = (void *)(l_addr + reloc->r_offset);
 669   unsigned long int const r_type = ELF64_R_TYPE (reloc->r_info);
 670
 671   if (r_type == R_ALPHA_JMP_SLOT)
 672     {
 673       /* Perform a RELATIVE reloc on the .got entry that transfers
 674          to the .plt.  */
 675       *reloc_addr += l_addr;
 676     }
 677   else if (r_type == R_ALPHA_NONE)
 678     return;
 679   else
 680     _dl_reloc_bad_type (map, r_type, 1);
 681 }
 682
 683 #endif /* RESOLVE */