/
machobj.c
2697 lines (2403 loc) · 81.7 KB
/
machobj.c
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// Copyright (c) 2009-2011 by Digital Mars
// All Rights Reserved
// written by Walter Bright
// http://www.digitalmars.com
// License for redistribution is by either the Artistic License
// in artistic.txt, or the GNU General Public License in gpl.txt.
// See the included readme.txt for details.
#if SCPP || MARS
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <ctype.h>
#if _WIN32 || __linux__
#include <malloc.h>
#endif
#if __linux__ || __APPLE__ || __FreeBSD__ || __OpenBSD__ || __sun
#include <signal.h>
#include <unistd.h>
#endif
#include "cc.h"
#include "global.h"
#include "code.h"
#include "type.h"
#include "mach.h"
#include "outbuf.h"
#include "filespec.h"
#include "cv4.h"
#include "cgcv.h"
#include "dt.h"
#include "aa.h"
#include "tinfo.h"
#if MACHOBJ
#if MARS
#include "mars.h"
#endif
#include "mach.h"
#include "dwarf.h"
// for x86_64
#define X86_64_RELOC_UNSIGNED 0
#define X86_64_RELOC_SIGNED 1
#define X86_64_RELOC_BRANCH 2
#define X86_64_RELOC_GOT_LOAD 3
#define X86_64_RELOC_GOT 4
#define X86_64_RELOC_SUBTRACTOR 5
#define X86_64_RELOC_SIGNED_1 6
#define X86_64_RELOC_SIGNED_2 7
#define X86_64_RELOC_SIGNED_4 8
static Outbuffer *fobjbuf;
static char __file__[] = __FILE__; // for tassert.h
#include "tassert.h"
#define DEST_LEN (IDMAX + IDOHD + 1)
char *obj_mangle2(Symbol *s,char *dest);
#if MARS
// C++ name mangling is handled by front end
#define cpp_mangle(s) ((s)->Sident)
#endif
/******************************************
*/
symbol *GOTsym; // global offset table reference
symbol *Obj::getGOTsym()
{
if (!GOTsym)
{
GOTsym = symbol_name("_GLOBAL_OFFSET_TABLE_",SCglobal,tspvoid);
}
return GOTsym;
}
static void objfile_write(FILE *fd, void *buffer, unsigned len);
STATIC char * objmodtoseg (const char *modname);
STATIC void objfixupp (struct FIXUP *);
STATIC void ledata_new (int seg,targ_size_t offset);
static long elf_align(targ_size_t size, long offset);
// The object file is built is several separate pieces
// String Table - String table for all other names
static Outbuffer *symtab_strings;
// Section Headers
Outbuffer *SECbuf; // Buffer to build section table in
#define SecHdrTab ((struct section *)SECbuf->buf)
#define SecHdrTab64 ((struct section_64 *)SECbuf->buf)
// The relocation for text and data seems to get lost.
// Try matching the order gcc output them
// This means defining the sections and then removing them if they are
// not used.
static int section_cnt; // Number of sections in table
#define SEC_TAB_INIT 16 // Initial number of sections in buffer
#define SEC_TAB_INC 4 // Number of sections to increment buffer by
#define SYM_TAB_INIT 100 // Initial number of symbol entries in buffer
#define SYM_TAB_INC 50 // Number of symbols to increment buffer by
/* Three symbol tables, because the different types of symbols
* are grouped into 3 different types (and a 4th for comdef's).
*/
static Outbuffer *local_symbuf;
static Outbuffer *public_symbuf;
static Outbuffer *extern_symbuf;
struct Comdef { symbol *sym; targ_size_t size; int count; };
static Outbuffer *comdef_symbuf; // Comdef's are stored here
static Outbuffer *indirectsymbuf1; // indirect symbol table of Symbol*'s
static int jumpTableSeg; // segment index for __jump_table
static Outbuffer *indirectsymbuf2; // indirect symbol table of Symbol*'s
static int pointersSeg; // segment index for __pointers
/* If an Obj::external_def() happens, set this to the string index,
* to be added last to the symbol table.
* Obviously, there can be only one.
*/
static IDXSTR extdef;
#if 0
#define STI_FILE 1 // Where file symbol table entry is
#define STI_TEXT 2
#define STI_DATA 3
#define STI_BSS 4
#define STI_GCC 5 // Where "gcc2_compiled" symbol is */
#define STI_RODAT 6 // Symbol for readonly data
#define STI_COM 8
#endif
// Each compiler segment is a section
// Predefined compiler segments CODE,DATA,CDATA,UDATA map to indexes
// into SegData[]
// New compiler segments are added to end.
/******************************
* Returns !=0 if this segment is a code segment.
*/
int seg_data::isCode()
{
// The codegen assumes that code->data references are indirect,
// but when CDATA is treated as code reftoident will emit a direct
// relocation.
if (this == SegData[CDATA])
return false;
if (I64)
{
//printf("SDshtidx = %d, x%x\n", SDshtidx, SecHdrTab64[SDshtidx].flags);
return strcmp(SecHdrTab64[SDshtidx].segname, "__TEXT") == 0;
}
else
{
//printf("SDshtidx = %d, x%x\n", SDshtidx, SecHdrTab[SDshtidx].flags);
return strcmp(SecHdrTab[SDshtidx].segname, "__TEXT") == 0;
}
}
seg_data **SegData;
int seg_count;
int seg_max;
int seg_tlsseg = UNKNOWN;
int seg_tlsseg_bss = UNKNOWN;
/*******************************************************
* Because the Mach-O relocations cannot be computed until after
* all the segments are written out, and we need more information
* than the Mach-O relocations provide, make our own relocation
* type. Later, translate to Mach-O relocation structure.
*/
struct Relocation
{ // Relocations are attached to the struct seg_data they refer to
targ_size_t offset; // location in segment to be fixed up
symbol *funcsym; // function in which offset lies, if any
symbol *targsym; // if !=NULL, then location is to be fixed up
// to address of this symbol
unsigned targseg; // if !=0, then location is to be fixed up
// to address of start of this segment
unsigned char rtype; // RELxxxx
#define RELaddr 0 // straight address
#define RELrel 1 // relative to location to be fixed up
short val; // 0, -1, -2, -4
};
/*******************************
* Output a string into a string table
* Input:
* strtab = string table for entry
* str = string to add
*
* Returns index into the specified string table.
*/
IDXSTR Obj::addstr(Outbuffer *strtab, const char *str)
{
//printf("Obj::addstr(strtab = %p str = '%s')\n",strtab,str);
IDXSTR idx = strtab->size(); // remember starting offset
strtab->writeString(str);
//printf("\tidx %d, new size %d\n",idx,strtab->size());
return idx;
}
/*******************************
* Find a string in a string table
* Input:
* strtab = string table for entry
* str = string to find
*
* Returns index into the specified string table or 0.
*/
static IDXSTR elf_findstr(Outbuffer *strtab, const char *str, const char *suffix)
{
const char *ent = (char *)strtab->buf+1;
const char *pend = ent+strtab->size() - 1;
const char *s = str;
const char *sx = suffix;
int len = strlen(str);
if (suffix)
len += strlen(suffix);
while(ent < pend)
{
if(*ent == 0) // end of table entry
{
if(*s == 0 && !sx) // end of string - found a match
{
return ent - (const char *)strtab->buf - len;
}
else // table entry too short
{
s = str; // back to beginning of string
sx = suffix;
ent++; // start of next table entry
}
}
else if (*s == 0 && sx && *sx == *ent)
{ // matched first string
s = sx+1; // switch to suffix
ent++;
sx = NULL;
}
else // continue comparing
{
if (*ent == *s)
{ // Have a match going
ent++;
s++;
}
else // no match
{
while(*ent != 0) // skip to end of entry
ent++;
ent++; // start of next table entry
s = str; // back to beginning of string
sx = suffix;
}
}
}
return 0; // never found match
}
/*******************************
* Output a mangled string into the symbol string table
* Input:
* str = string to add
*
* Returns index into the table.
*/
static IDXSTR elf_addmangled(Symbol *s)
{
//printf("elf_addmangled(%s)\n", s->Sident);
char dest[DEST_LEN];
char *destr;
const char *name;
int len;
IDXSTR namidx;
namidx = symtab_strings->size();
destr = obj_mangle2(s, dest);
name = destr;
if (CPP && name[0] == '_' && name[1] == '_')
{
if (strncmp(name,"__ct__",6) == 0)
name += 4;
#if 0
switch(name[2])
{
case 'c':
if (strncmp(name,"__ct__",6) == 0)
name += 4;
break;
case 'd':
if (strcmp(name,"__dl__FvP") == 0)
name = "__builtin_delete";
break;
case 'v':
//if (strcmp(name,"__vec_delete__FvPiUIPi") == 0)
//name = "__builtin_vec_del";
//else
//if (strcmp(name,"__vn__FPUI") == 0)
//name = "__builtin_vec_new";
break;
case 'n':
if (strcmp(name,"__nw__FPUI") == 0)
name = "__builtin_new";
break;
}
#endif
}
else if (tyfunc(s->ty()) && s->Sfunc && s->Sfunc->Fredirect)
name = s->Sfunc->Fredirect;
len = strlen(name);
symtab_strings->reserve(len+1);
strcpy((char *)symtab_strings->p,name);
symtab_strings->setsize(namidx+len+1);
if (destr != dest) // if we resized result
mem_free(destr);
//dbg_printf("\telf_addmagled symtab_strings %s namidx %d len %d size %d\n",name, namidx,len,symtab_strings->size());
return namidx;
}
/**************************
* Ouput read only data and generate a symbol for it.
*
*/
symbol * Obj::sym_cdata(tym_t ty,char *p,int len)
{
symbol *s;
#if 0
if (I64)
{
alignOffset(DATA, tysize(ty));
s = symboldata(Doffset, ty);
SegData[DATA]->SDbuf->write(p,len);
s->Sseg = DATA;
s->Soffset = Doffset; // Remember its offset into DATA section
Doffset += len;
}
else
#endif
{
//printf("Obj::sym_cdata(ty = %x, p = %x, len = %d, CDoffset = %x)\n", ty, p, len, CDoffset);
alignOffset(CDATA, tysize(ty));
s = symboldata(CDoffset, ty);
s->Sseg = CDATA;
//Obj::pubdef(CDATA, s, CDoffset);
Obj::bytes(CDATA, CDoffset, len, p);
}
s->Sfl = /*(config.flags3 & CFG3pic) ? FLgotoff :*/ FLextern;
return s;
}
/**************************
* Ouput read only data for data
*
*/
int Obj::data_readonly(char *p, int len, int *pseg)
{
int oldoff = CDoffset;
SegData[CDATA]->SDbuf->reserve(len);
SegData[CDATA]->SDbuf->writen(p,len);
CDoffset += len;
*pseg = CDATA;
return oldoff;
}
int Obj::data_readonly(char *p, int len)
{
int pseg;
return Obj::data_readonly(p, len, &pseg);
}
/******************************
* Perform initialization that applies to all .o output files.
* Called before any other obj_xxx routines
*/
Obj *Obj::init(Outbuffer *objbuf, const char *filename, const char *csegname)
{
//printf("Obj::init()\n");
MachObj *obj = new MachObj();
cseg = CODE;
fobjbuf = objbuf;
seg_tlsseg = UNKNOWN;
seg_tlsseg_bss = UNKNOWN;
GOTsym = NULL;
// Initialize buffers
if (symtab_strings)
symtab_strings->setsize(1);
else
{ symtab_strings = new Outbuffer(1024);
symtab_strings->reserve(2048);
symtab_strings->writeByte(0);
}
if (!local_symbuf)
local_symbuf = new Outbuffer(sizeof(symbol *) * SYM_TAB_INIT);
local_symbuf->setsize(0);
if (!public_symbuf)
public_symbuf = new Outbuffer(sizeof(symbol *) * SYM_TAB_INIT);
public_symbuf->setsize(0);
if (!extern_symbuf)
extern_symbuf = new Outbuffer(sizeof(symbol *) * SYM_TAB_INIT);
extern_symbuf->setsize(0);
if (!comdef_symbuf)
comdef_symbuf = new Outbuffer(sizeof(symbol *) * SYM_TAB_INIT);
comdef_symbuf->setsize(0);
extdef = 0;
if (indirectsymbuf1)
indirectsymbuf1->setsize(0);
jumpTableSeg = 0;
if (indirectsymbuf2)
indirectsymbuf2->setsize(0);
pointersSeg = 0;
// Initialize segments for CODE, DATA, UDATA and CDATA
size_t struct_section_size = I64 ? sizeof(struct section_64) : sizeof(struct section);
if (SECbuf)
{
SECbuf->setsize(struct_section_size);
}
else
{
SECbuf = new Outbuffer(SYM_TAB_INC * struct_section_size);
SECbuf->reserve(SEC_TAB_INIT * struct_section_size);
// Ignore the first section - section numbers start at 1
SECbuf->writezeros(struct_section_size);
}
section_cnt = 1;
seg_count = 0;
int align = I64 ? 4 : 2; // align to 16 bytes for floating point
MachObj::getsegment("__text", "__TEXT", 2, S_REGULAR | S_ATTR_PURE_INSTRUCTIONS | S_ATTR_SOME_INSTRUCTIONS);
MachObj::getsegment("__data", "__DATA", align, S_REGULAR); // DATA
MachObj::getsegment("__const", "__TEXT", 2, S_REGULAR); // CDATA
MachObj::getsegment("__bss", "__DATA", 4, S_ZEROFILL); // UDATA
MachObj::getsegment("__const", "__DATA", align, S_REGULAR); // CDATAREL
if (config.fulltypes)
dwarf_initfile(filename);
return obj;
}
/**************************
* Initialize the start of object output for this particular .o file.
*
* Input:
* filename: Name of source file
* csegname: User specified default code segment name
*/
void Obj::initfile(const char *filename, const char *csegname, const char *modname)
{
//dbg_printf("Obj::initfile(filename = %s, modname = %s)\n",filename,modname);
#if SCPP
if (csegname && *csegname && strcmp(csegname,".text"))
{ // Define new section and make it the default for cseg segment
// NOTE: cseg is initialized to CODE
IDXSEC newsecidx;
Elf32_Shdr *newtextsec;
IDXSYM newsymidx;
assert(!I64); // fix later
SegData[cseg]->SDshtidx = newsecidx =
elf_newsection(csegname,0,SHT_PROGDEF,SHF_ALLOC|SHF_EXECINSTR);
newtextsec = &SecHdrTab[newsecidx];
newtextsec->sh_addralign = 4;
SegData[cseg]->SDsymidx =
elf_addsym(0, 0, 0, STT_SECTION, STB_LOCAL, newsecidx);
}
#endif
if (config.fulltypes)
dwarf_initmodule(filename, modname);
}
/************************************
* Patch pseg/offset by adding in the vmaddr difference from
* pseg/offset to start of seg.
*/
int32_t *patchAddr(int seg, targ_size_t offset)
{
return(int32_t *)(fobjbuf->buf + SecHdrTab[SegData[seg]->SDshtidx].offset + offset);
}
int32_t *patchAddr64(int seg, targ_size_t offset)
{
return(int32_t *)(fobjbuf->buf + SecHdrTab64[SegData[seg]->SDshtidx].offset + offset);
}
void patch(seg_data *pseg, targ_size_t offset, int seg, targ_size_t value)
{
//printf("patch(offset = x%04x, seg = %d, value = x%llx)\n", (unsigned)offset, seg, value);
if (I64)
{
int32_t *p = (int32_t *)(fobjbuf->buf + SecHdrTab64[pseg->SDshtidx].offset + offset);
#if 0
printf("\taddr1 = x%llx\n\taddr2 = x%llx\n\t*p = x%llx\n\tdelta = x%llx\n",
SecHdrTab64[pseg->SDshtidx].addr,
SecHdrTab64[SegData[seg]->SDshtidx].addr,
*p,
SecHdrTab64[SegData[seg]->SDshtidx].addr -
(SecHdrTab64[pseg->SDshtidx].addr + offset));
#endif
*p += SecHdrTab64[SegData[seg]->SDshtidx].addr -
(SecHdrTab64[pseg->SDshtidx].addr - value);
}
else
{
int32_t *p = (int32_t *)(fobjbuf->buf + SecHdrTab[pseg->SDshtidx].offset + offset);
#if 0
printf("\taddr1 = x%x\n\taddr2 = x%x\n\t*p = x%x\n\tdelta = x%x\n",
SecHdrTab[pseg->SDshtidx].addr,
SecHdrTab[SegData[seg]->SDshtidx].addr,
*p,
SecHdrTab[SegData[seg]->SDshtidx].addr -
(SecHdrTab[pseg->SDshtidx].addr + offset));
#endif
*p += SecHdrTab[SegData[seg]->SDshtidx].addr -
(SecHdrTab[pseg->SDshtidx].addr - value);
}
}
/***************************
* Number symbols so they are
* ordered as locals, public and then extern/comdef
*/
void mach_numbersyms()
{
//printf("mach_numbersyms()\n");
int n = 0;
int dim;
dim = local_symbuf->size() / sizeof(symbol *);
for (int i = 0; i < dim; i++)
{ symbol *s = ((symbol **)local_symbuf->buf)[i];
s->Sxtrnnum = n;
n++;
}
dim = public_symbuf->size() / sizeof(symbol *);
for (int i = 0; i < dim; i++)
{ symbol *s = ((symbol **)public_symbuf->buf)[i];
s->Sxtrnnum = n;
n++;
}
dim = extern_symbuf->size() / sizeof(symbol *);
for (int i = 0; i < dim; i++)
{ symbol *s = ((symbol **)extern_symbuf->buf)[i];
s->Sxtrnnum = n;
n++;
}
dim = comdef_symbuf->size() / sizeof(Comdef);
for (int i = 0; i < dim; i++)
{ Comdef *c = ((Comdef *)comdef_symbuf->buf) + i;
c->sym->Sxtrnnum = n;
n++;
}
}
/***************************
* Fixup and terminate object file.
*/
void Obj::termfile()
{
//dbg_printf("Obj::termfile\n");
if (configv.addlinenumbers)
{
dwarf_termmodule();
}
}
/*********************************
* Terminate package.
*/
void Obj::term(const char *objfilename)
{
//printf("Obj::term()\n");
#if SCPP
if (!errcnt)
#endif
{
outfixlist(); // backpatches
}
if (configv.addlinenumbers)
{
dwarf_termfile();
}
#if SCPP
if (errcnt)
return;
#endif
/* Write out the object file in the following order:
* header
* commands
* segment_command
* { sections }
* symtab_command
* dysymtab_command
* { segment contents }
* { relocations }
* symbol table
* string table
* indirect symbol table
*/
unsigned foffset;
unsigned headersize;
unsigned sizeofcmds;
// Write out the bytes for the header
if (I64)
{
mach_header_64 header;
header.magic = MH_MAGIC_64;
header.cputype = CPU_TYPE_X86_64;
header.cpusubtype = CPU_SUBTYPE_I386_ALL;
header.filetype = MH_OBJECT;
header.ncmds = 3;
header.sizeofcmds = sizeof(segment_command_64) +
(section_cnt - 1) * sizeof(struct section_64) +
sizeof(symtab_command) +
sizeof(dysymtab_command);
header.flags = MH_SUBSECTIONS_VIA_SYMBOLS;
header.reserved = 0;
fobjbuf->write(&header, sizeof(header));
foffset = sizeof(header); // start after header
headersize = sizeof(header);
sizeofcmds = header.sizeofcmds;
// Write the actual data later
fobjbuf->writezeros(header.sizeofcmds);
foffset += header.sizeofcmds;
}
else
{
mach_header header;
header.magic = MH_MAGIC;
header.cputype = CPU_TYPE_I386;
header.cpusubtype = CPU_SUBTYPE_I386_ALL;
header.filetype = MH_OBJECT;
header.ncmds = 3;
header.sizeofcmds = sizeof(segment_command) +
(section_cnt - 1) * sizeof(struct section) +
sizeof(symtab_command) +
sizeof(dysymtab_command);
header.flags = MH_SUBSECTIONS_VIA_SYMBOLS;
fobjbuf->write(&header, sizeof(header));
foffset = sizeof(header); // start after header
headersize = sizeof(header);
sizeofcmds = header.sizeofcmds;
// Write the actual data later
fobjbuf->writezeros(header.sizeofcmds);
foffset += header.sizeofcmds;
}
struct segment_command segment_cmd;
struct segment_command_64 segment_cmd64;
struct symtab_command symtab_cmd;
struct dysymtab_command dysymtab_cmd;
memset(&segment_cmd, 0, sizeof(segment_cmd));
memset(&segment_cmd64, 0, sizeof(segment_cmd64));
memset(&symtab_cmd, 0, sizeof(symtab_cmd));
memset(&dysymtab_cmd, 0, sizeof(dysymtab_cmd));
if (I64)
{
segment_cmd64.cmd = LC_SEGMENT_64;
segment_cmd64.cmdsize = sizeof(segment_cmd64) +
(section_cnt - 1) * sizeof(struct section_64);
segment_cmd64.nsects = section_cnt - 1;
segment_cmd64.maxprot = 7;
segment_cmd64.initprot = 7;
}
else
{
segment_cmd.cmd = LC_SEGMENT;
segment_cmd.cmdsize = sizeof(segment_cmd) +
(section_cnt - 1) * sizeof(struct section);
segment_cmd.nsects = section_cnt - 1;
segment_cmd.maxprot = 7;
segment_cmd.initprot = 7;
}
symtab_cmd.cmd = LC_SYMTAB;
symtab_cmd.cmdsize = sizeof(symtab_cmd);
dysymtab_cmd.cmd = LC_DYSYMTAB;
dysymtab_cmd.cmdsize = sizeof(dysymtab_cmd);
/* If a __pointers section was emitted, need to set the .reserved1
* field to the symbol index in the indirect symbol table of the
* start of the __pointers symbols.
*/
if (pointersSeg)
{
seg_data *pseg = SegData[pointersSeg];
if (I64)
{
struct section_64 *psechdr = &SecHdrTab64[pseg->SDshtidx]; // corresponding section
psechdr->reserved1 = indirectsymbuf1
? indirectsymbuf1->size() / sizeof(Symbol *)
: 0;
}
else
{
struct section *psechdr = &SecHdrTab[pseg->SDshtidx]; // corresponding section
psechdr->reserved1 = indirectsymbuf1
? indirectsymbuf1->size() / sizeof(Symbol *)
: 0;
}
}
// Walk through sections determining size and file offsets
//
// First output individual section data associate with program
// code and data
//
foffset = elf_align(I64 ? 8 : 4, foffset);
if (I64)
segment_cmd64.fileoff = foffset;
else
segment_cmd.fileoff = foffset;
unsigned vmaddr = 0;
//printf("Setup offsets and sizes foffset %d\n\tsection_cnt %d, seg_count %d\n",foffset,section_cnt,seg_count);
// Zero filled segments go at the end, so go through segments twice
for (int i = 0; i < 2; i++)
{
for (int seg = 1; seg <= seg_count; seg++)
{
seg_data *pseg = SegData[seg];
if (I64)
{
struct section_64 *psechdr = &SecHdrTab64[pseg->SDshtidx]; // corresponding section
// Do zero-fill the second time through this loop
if (i ^ (psechdr->flags == S_ZEROFILL))
continue;
int align = 1 << psechdr->align;
while (align < pseg->SDalignment)
{
psechdr->align += 1;
align <<= 1;
}
foffset = elf_align(align, foffset);
vmaddr = (vmaddr + align - 1) & ~(align - 1);
if (psechdr->flags == S_ZEROFILL)
{
psechdr->offset = 0;
psechdr->size = pseg->SDoffset; // accumulated size
}
else
{
psechdr->offset = foffset;
psechdr->size = 0;
//printf("\tsection name %s,", psechdr->sectname);
if (pseg->SDbuf && pseg->SDbuf->size())
{
//printf("\tsize %d\n", pseg->SDbuf->size());
psechdr->size = pseg->SDbuf->size();
fobjbuf->write(pseg->SDbuf->buf, psechdr->size);
foffset += psechdr->size;
}
}
psechdr->addr = vmaddr;
vmaddr += psechdr->size;
//printf(" assigned offset %d, size %d\n", foffset, psechdr->sh_size);
}
else
{
struct section *psechdr = &SecHdrTab[pseg->SDshtidx]; // corresponding section
// Do zero-fill the second time through this loop
if (i ^ (psechdr->flags == S_ZEROFILL))
continue;
int align = 1 << psechdr->align;
while (align < pseg->SDalignment)
{
psechdr->align += 1;
align <<= 1;
}
foffset = elf_align(align, foffset);
vmaddr = (vmaddr + align - 1) & ~(align - 1);
if (psechdr->flags == S_ZEROFILL)
{
psechdr->offset = 0;
psechdr->size = pseg->SDoffset; // accumulated size
}
else
{
psechdr->offset = foffset;
psechdr->size = 0;
//printf("\tsection name %s,", psechdr->sectname);
if (pseg->SDbuf && pseg->SDbuf->size())
{
//printf("\tsize %d\n", pseg->SDbuf->size());
psechdr->size = pseg->SDbuf->size();
fobjbuf->write(pseg->SDbuf->buf, psechdr->size);
foffset += psechdr->size;
}
}
psechdr->addr = vmaddr;
vmaddr += psechdr->size;
//printf(" assigned offset %d, size %d\n", foffset, psechdr->sh_size);
}
}
}
if (I64)
{
segment_cmd64.vmsize = vmaddr;
segment_cmd64.filesize = foffset - segment_cmd64.fileoff;
/* Bugzilla 5331: Apparently having the filesize field greater than the vmsize field is an
* error, and is happening sometimes.
*/
if (segment_cmd64.filesize > vmaddr)
segment_cmd64.vmsize = segment_cmd64.filesize;
}
else
{
segment_cmd.vmsize = vmaddr;
segment_cmd.filesize = foffset - segment_cmd.fileoff;
/* Bugzilla 5331: Apparently having the filesize field greater than the vmsize field is an
* error, and is happening sometimes.
*/
if (segment_cmd.filesize > vmaddr)
segment_cmd.vmsize = segment_cmd.filesize;
}
// Put out relocation data
mach_numbersyms();
for (int seg = 1; seg <= seg_count; seg++)
{
seg_data *pseg = SegData[seg];
struct section *psechdr = NULL;
struct section_64 *psechdr64 = NULL;
if (I64)
{
psechdr64 = &SecHdrTab64[pseg->SDshtidx]; // corresponding section
//printf("psechdr->addr = x%llx\n", psechdr64->addr);
}
else
{
psechdr = &SecHdrTab[pseg->SDshtidx]; // corresponding section
//printf("psechdr->addr = x%x\n", psechdr->addr);
}
foffset = elf_align(I64 ? 8 : 4, foffset);
unsigned reloff = foffset;
unsigned nreloc = 0;
if (pseg->SDrel)
{ Relocation *r = (Relocation *)pseg->SDrel->buf;
Relocation *rend = (Relocation *)(pseg->SDrel->buf + pseg->SDrel->size());
for (; r != rend; r++)
{ symbol *s = r->targsym;
const char *rs = r->rtype == RELaddr ? "addr" : "rel";
//printf("%d:x%04llx : tseg %d tsym %s REL%s\n", seg, r->offset, r->targseg, s ? s->Sident : "0", rs);
relocation_info rel;
scattered_relocation_info srel;
if (s)
{
//printf("Relocation\n");
//symbol_print(s);
if (pseg->isCode())
{
if (I64)
{
rel.r_type = (r->rtype == RELrel)
? X86_64_RELOC_BRANCH
: X86_64_RELOC_SIGNED;
if (r->val == -1)
rel.r_type = X86_64_RELOC_SIGNED_1;
else if (r->val == -2)
rel.r_type = X86_64_RELOC_SIGNED_2;
if (r->val == -4)
rel.r_type = X86_64_RELOC_SIGNED_4;
if (s->Sclass == SCextern ||
s->Sclass == SCcomdef ||
s->Sclass == SCcomdat ||
s->Sclass == SCglobal)
{
if ((s->Sfl == FLfunc || s->Sfl == FLextern || s->Sclass == SCglobal || s->Sclass == SCcomdat || s->Sclass == SCcomdef) && r->rtype == RELaddr)
rel.r_type = X86_64_RELOC_GOT_LOAD;
rel.r_address = r->offset;
rel.r_symbolnum = s->Sxtrnnum;
rel.r_pcrel = 1;
rel.r_length = 2;
rel.r_extern = 1;
fobjbuf->write(&rel, sizeof(rel));
foffset += sizeof(rel);
nreloc++;
continue;
}
else
{
rel.r_address = r->offset;
rel.r_symbolnum = s->Sseg;
rel.r_pcrel = 1;
rel.r_length = 2;
rel.r_extern = 0;
fobjbuf->write(&rel, sizeof(rel));
foffset += sizeof(rel);
nreloc++;
int32_t *p = patchAddr64(seg, r->offset);
// Absolute address; add in addr of start of targ seg
//printf("*p = x%x, .addr = x%x, Soffset = x%x\n", *p, (int)SecHdrTab64[SegData[s->Sseg]->SDshtidx].addr, (int)s->Soffset);
//printf("pseg = x%x, r->offset = x%x\n", (int)SecHdrTab64[pseg->SDshtidx].addr, (int)r->offset);
*p += SecHdrTab64[SegData[s->Sseg]->SDshtidx].addr;
*p += s->Soffset;
*p -= SecHdrTab64[pseg->SDshtidx].addr + r->offset + 4;
//patch(pseg, r->offset, s->Sseg, s->Soffset);
continue;
}
}
}
else
{
if (s->Sclass == SCextern ||
s->Sclass == SCcomdef ||
s->Sclass == SCcomdat)
{
rel.r_address = r->offset;
rel.r_symbolnum = s->Sxtrnnum;
rel.r_pcrel = 0;
rel.r_length = 2;
rel.r_extern = 1;
rel.r_type = GENERIC_RELOC_VANILLA;
if (I64)
{
rel.r_type = X86_64_RELOC_UNSIGNED;
rel.r_length = 3;
}
fobjbuf->write(&rel, sizeof(rel));
foffset += sizeof(rel);
nreloc++;
continue;
}