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/*
* recordmcount.h
*
* This code was taken out of recordmcount.c written by
* Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved.
*
* The original code had the same algorithms for both 32bit
* and 64bit ELF files, but the code was duplicated to support
* the difference in structures that were used. This
* file creates a macro of everything that is different between
* the 64 and 32 bit code, such that by including this header
* twice we can create both sets of functions by including this
* header once with RECORD_MCOUNT_64 undefined, and again with
* it defined.
*
* This conversion to macros was done by:
* Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc.
*
* Licensed under the GNU General Public License, version 2 (GPLv2).
*/
#undef append_func
#undef sift_rel_mcount
#undef find_secsym_ndx
#undef __has_rel_mcount
#undef has_rel_mcount
#undef tot_relsize
#undef do_func
#undef Elf_Ehdr
#undef Elf_Shdr
#undef Elf_Rel
#undef Elf_Rela
#undef Elf_Sym
#undef ELF_R_SYM
#undef Elf_r_sym
#undef ELF_R_INFO
#undef Elf_r_info
#undef ELF_ST_BIND
#undef fn_ELF_R_SYM
#undef fn_ELF_R_INFO
#undef uint_t
#undef _w
#undef _align
#undef _size
#ifdef RECORD_MCOUNT_64
# define append_func append64
# define sift_rel_mcount sift64_rel_mcount
# define find_secsym_ndx find64_secsym_ndx
# define __has_rel_mcount __has64_rel_mcount
# define has_rel_mcount has64_rel_mcount
# define tot_relsize tot64_relsize
# define do_func do64
# define Elf_Ehdr Elf64_Ehdr
# define Elf_Shdr Elf64_Shdr
# define Elf_Rel Elf64_Rel
# define Elf_Rela Elf64_Rela
# define Elf_Sym Elf64_Sym
# define ELF_R_SYM ELF64_R_SYM
# define Elf_r_sym Elf64_r_sym
# define ELF_R_INFO ELF64_R_INFO
# define Elf_r_info Elf64_r_info
# define ELF_ST_BIND ELF64_ST_BIND
# define fn_ELF_R_SYM fn_ELF64_R_SYM
# define fn_ELF_R_INFO fn_ELF64_R_INFO
# define uint_t uint64_t
# define _w w8
# define _align 7u
# define _size 8
#else
# define append_func append32
# define sift_rel_mcount sift32_rel_mcount
# define find_secsym_ndx find32_secsym_ndx
# define __has_rel_mcount __has32_rel_mcount
# define has_rel_mcount has32_rel_mcount
# define tot_relsize tot32_relsize
# define do_func do32
# define Elf_Ehdr Elf32_Ehdr
# define Elf_Shdr Elf32_Shdr
# define Elf_Rel Elf32_Rel
# define Elf_Rela Elf32_Rela
# define Elf_Sym Elf32_Sym
# define ELF_R_SYM ELF32_R_SYM
# define Elf_r_sym Elf32_r_sym
# define ELF_R_INFO ELF32_R_INFO
# define Elf_r_info Elf32_r_info
# define ELF_ST_BIND ELF32_ST_BIND
# define fn_ELF_R_SYM fn_ELF32_R_SYM
# define fn_ELF_R_INFO fn_ELF32_R_INFO
# define uint_t uint32_t
# define _w w
# define _align 3u
# define _size 4
#endif
/* Functions and pointers that 64-bit EM_MIPS can override. */
static uint_t fn_ELF_R_SYM(Elf_Rel const *rp)
{
return ELF_R_SYM(_w(rp->r_info));
}
static uint_t (*Elf_r_sym)(Elf_Rel const *rp) = fn_ELF_R_SYM;
static void fn_ELF_R_INFO(Elf_Rel *const rp, unsigned sym, unsigned type)
{
rp->r_info = ELF_R_INFO(sym, type);
}
static void (*Elf_r_info)(Elf_Rel *const rp, unsigned sym, unsigned type) = fn_ELF_R_INFO;
/* Append the new shstrtab, Elf_Shdr[], __mcount_loc and its relocations. */
static void append_func(Elf_Ehdr *const ehdr,
Elf_Shdr *const shstr,
uint_t const *const mloc0,
uint_t const *const mlocp,
Elf_Rel const *const mrel0,
Elf_Rel const *const mrelp,
unsigned int const rel_entsize,
unsigned int const symsec_sh_link)
{
/* Begin constructing output file */
Elf_Shdr mcsec;
char const *mc_name = (sizeof(Elf_Rela) == rel_entsize)
? ".rela__mcount_loc"
: ".rel__mcount_loc";
unsigned const old_shnum = w2(ehdr->e_shnum);
uint_t const old_shoff = _w(ehdr->e_shoff);
uint_t const old_shstr_sh_size = _w(shstr->sh_size);
uint_t const old_shstr_sh_offset = _w(shstr->sh_offset);
uint_t t = 1 + strlen(mc_name) + _w(shstr->sh_size);
uint_t new_e_shoff;
shstr->sh_size = _w(t);
shstr->sh_offset = _w(sb.st_size);
t += sb.st_size;
t += (_align & -t); /* word-byte align */
new_e_shoff = t;
/* body for new shstrtab */
ulseek(fd_map, sb.st_size, SEEK_SET);
uwrite(fd_map, old_shstr_sh_offset + (void *)ehdr, old_shstr_sh_size);
uwrite(fd_map, mc_name, 1 + strlen(mc_name));
/* old(modified) Elf_Shdr table, word-byte aligned */
ulseek(fd_map, t, SEEK_SET);
t += sizeof(Elf_Shdr) * old_shnum;
uwrite(fd_map, old_shoff + (void *)ehdr,
sizeof(Elf_Shdr) * old_shnum);
/* new sections __mcount_loc and .rel__mcount_loc */
t += 2*sizeof(mcsec);
mcsec.sh_name = w((sizeof(Elf_Rela) == rel_entsize) + strlen(".rel")
+ old_shstr_sh_size);
mcsec.sh_type = w(SHT_PROGBITS);
mcsec.sh_flags = _w(SHF_ALLOC);
mcsec.sh_addr = 0;
mcsec.sh_offset = _w(t);
mcsec.sh_size = _w((void *)mlocp - (void *)mloc0);
mcsec.sh_link = 0;
mcsec.sh_info = 0;
mcsec.sh_addralign = _w(_size);
mcsec.sh_entsize = _w(_size);
uwrite(fd_map, &mcsec, sizeof(mcsec));
mcsec.sh_name = w(old_shstr_sh_size);
mcsec.sh_type = (sizeof(Elf_Rela) == rel_entsize)
? w(SHT_RELA)
: w(SHT_REL);
mcsec.sh_flags = 0;
mcsec.sh_addr = 0;
mcsec.sh_offset = _w((void *)mlocp - (void *)mloc0 + t);
mcsec.sh_size = _w((void *)mrelp - (void *)mrel0);
mcsec.sh_link = w(symsec_sh_link);
mcsec.sh_info = w(old_shnum);
mcsec.sh_addralign = _w(_size);
mcsec.sh_entsize = _w(rel_entsize);
uwrite(fd_map, &mcsec, sizeof(mcsec));
uwrite(fd_map, mloc0, (void *)mlocp - (void *)mloc0);
uwrite(fd_map, mrel0, (void *)mrelp - (void *)mrel0);
ehdr->e_shoff = _w(new_e_shoff);
ehdr->e_shnum = w2(2 + w2(ehdr->e_shnum)); /* {.rel,}__mcount_loc */
ulseek(fd_map, 0, SEEK_SET);
uwrite(fd_map, ehdr, sizeof(*ehdr));
}
/*
* Look at the relocations in order to find the calls to mcount.
* Accumulate the section offsets that are found, and their relocation info,
* onto the end of the existing arrays.
*/
static uint_t *sift_rel_mcount(uint_t *mlocp,
unsigned const offbase,
Elf_Rel **const mrelpp,
Elf_Shdr const *const relhdr,
Elf_Ehdr const *const ehdr,
unsigned const recsym,
uint_t const recval,
unsigned const reltype)
{
uint_t *const mloc0 = mlocp;
Elf_Rel *mrelp = *mrelpp;
Elf_Shdr *const shdr0 = (Elf_Shdr *)(_w(ehdr->e_shoff)
+ (void *)ehdr);
unsigned const symsec_sh_link = w(relhdr->sh_link);
Elf_Shdr const *const symsec = &shdr0[symsec_sh_link];
Elf_Sym const *const sym0 = (Elf_Sym const *)(_w(symsec->sh_offset)
+ (void *)ehdr);
Elf_Shdr const *const strsec = &shdr0[w(symsec->sh_link)];
char const *const str0 = (char const *)(_w(strsec->sh_offset)
+ (void *)ehdr);
Elf_Rel const *const rel0 = (Elf_Rel const *)(_w(relhdr->sh_offset)
+ (void *)ehdr);
unsigned rel_entsize = _w(relhdr->sh_entsize);
unsigned const nrel = _w(relhdr->sh_size) / rel_entsize;
Elf_Rel const *relp = rel0;
unsigned mcountsym = 0;
unsigned t;
for (t = nrel; t; --t) {
if (!mcountsym) {
Elf_Sym const *const symp =
&sym0[Elf_r_sym(relp)];
char const *symname = &str0[w(symp->st_name)];
if ('.' == symname[0])
++symname; /* ppc64 hack */
if (0 == strcmp((('_' == gpfx) ? "_mcount" : "mcount"),
symname))
mcountsym = Elf_r_sym(relp);
}
if (mcountsym == Elf_r_sym(relp)) {
uint_t const addend = _w(_w(relp->r_offset) - recval);
mrelp->r_offset = _w(offbase
+ ((void *)mlocp - (void *)mloc0));
Elf_r_info(mrelp, recsym, reltype);
if (sizeof(Elf_Rela
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