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Diffstat (limited to 'gcc/config/pa/fptr.c')
| -rw-r--r-- | gcc/config/pa/fptr.c | 131 |
1 files changed, 0 insertions, 131 deletions
diff --git a/gcc/config/pa/fptr.c b/gcc/config/pa/fptr.c deleted file mode 100644 index 320d182..0000000 --- a/gcc/config/pa/fptr.c +++ /dev/null @@ -1,131 +0,0 @@ -/* Subroutine for function pointer canonicalization on PA-RISC with ELF32. - Copyright 2002, 2003, 2004, 2007, 2009 Free Software Foundation, Inc. - Contributed by John David Anglin (dave.anglin@nrc.ca). - -This file is part of GCC. - -GCC is free software; you can redistribute it and/or modify it under -the terms of the GNU General Public License as published by the Free -Software Foundation; either version 3, or (at your option) any later -version. - -GCC is distributed in the hope that it will be useful, but WITHOUT ANY -WARRANTY; without even the implied warranty of MERCHANTABILITY or -FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -for more details. - -Under Section 7 of GPL version 3, you are granted additional -permissions described in the GCC Runtime Library Exception, version -3.1, as published by the Free Software Foundation. - -You should have received a copy of the GNU General Public License and -a copy of the GCC Runtime Library Exception along with this program; -see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -<http://www.gnu.org/licenses/>. */ - - -/* WARNING: The code is this function depends on internal and undocumented - details of the GNU linker and dynamic loader as implemented for parisc - linux. */ - -/* This MUST match the defines sysdeps/hppa/dl-machine.h and - bfd/elf32-hppa.c. */ -#define GOT_FROM_PLT_STUB (4*4) - -/* List of byte offsets in _dl_runtime_resolve to search for "bl" branches. - The first "bl" branch instruction found MUST be a call to fixup. See - the define for TRAMPOLINE_TEMPLATE in sysdeps/hppa/dl-machine.h. If - the trampoline template is changed, the list must be appropriately - updated. The offset of -4 allows for a magic branch at the start of - the template should it be necessary to change the current branch - position. */ -#define NOFFSETS 2 -static int fixup_branch_offset[NOFFSETS] = { 32, -4 }; - -#define GET_FIELD(X, FROM, TO) \ - ((X) >> (31 - (TO)) & ((1 << ((TO) - (FROM) + 1)) - 1)) -#define SIGN_EXTEND(VAL,BITS) \ - ((int) ((VAL) >> ((BITS) - 1) ? (-1 << (BITS)) | (VAL) : (VAL))) - -struct link_map; -typedef int (*fptr_t) (void); -typedef int (*fixup_t) (struct link_map *, unsigned int); -extern unsigned int _GLOBAL_OFFSET_TABLE_; - -/* __canonicalize_funcptr_for_compare must be hidden so that it is not - placed in the dynamic symbol table. Like millicode functions, it - must be linked into all binaries in order access the got table of - that binary. However, we don't use the millicode calling convention - and the routine must be a normal function so that it can be compiled - as pic code. */ -unsigned int __canonicalize_funcptr_for_compare (fptr_t) - __attribute__ ((visibility ("hidden"))); - -unsigned int -__canonicalize_funcptr_for_compare (fptr_t fptr) -{ - static unsigned int fixup_plabel[2]; - static fixup_t fixup; - unsigned int *plabel, *got; - - /* -1 and page 0 are special. -1 is used in crtend to mark the end of - a list of function pointers. Also return immediately if the plabel - bit is not set in the function pointer. In this case, the function - pointer points directly to the function. */ - if ((int) fptr == -1 || (unsigned int) fptr < 4096 || !((int) fptr & 2)) - return (unsigned int) fptr; - - /* The function pointer points to a function descriptor (plabel). If - the plabel hasn't been resolved, the first word of the plabel points - to the entry of the PLT stub just before the global offset table. - The second word in the plabel contains the relocation offset for the - function. */ - plabel = (unsigned int *) ((unsigned int) fptr & ~3); - got = (unsigned int *) (plabel[0] + GOT_FROM_PLT_STUB); - - /* Return the address of the function if the plabel has been resolved. */ - if (got != &_GLOBAL_OFFSET_TABLE_) - return plabel[0]; - - /* Initialize our plabel for calling fixup if we haven't done so already. - This code needs to be thread safe but we don't have to be too careful - as the result is invariant. */ - if (!fixup) - { - int i; - unsigned int *iptr; - - /* Find the first "bl" branch in the offset search list. This is a - call to fixup or a magic branch to fixup at the beginning of the - trampoline template. The fixup function does the actual runtime - resolution of function descriptors. We only look for "bl" branches - with a 17-bit pc-relative displacement. */ - for (i = 0; i < NOFFSETS; i++) - { - iptr = (unsigned int *) (got[-2] + fixup_branch_offset[i]); - if ((*iptr & 0xfc00e000) == 0xe8000000) - break; - } - - /* This should not happen... */ - if (i == NOFFSETS) - return ~0; - - /* Extract the 17-bit displacement from the instruction. */ - iptr += SIGN_EXTEND (GET_FIELD (*iptr, 19, 28) | - GET_FIELD (*iptr, 29, 29) << 10 | - GET_FIELD (*iptr, 11, 15) << 11 | - GET_FIELD (*iptr, 31, 31) << 16, 17); - - /* Build a plabel for an indirect call to fixup. */ - fixup_plabel[0] = (unsigned int) iptr + 8; /* address of fixup */ - fixup_plabel[1] = got[-1]; /* ltp for fixup */ - fixup = (fixup_t) ((int) fixup_plabel | 3); - } - - /* Call fixup to resolve the function address. got[1] contains the - link_map pointer and plabel[1] the relocation offset. */ - fixup ((struct link_map *) got[1], plabel[1]); - - return plabel[0]; -} |