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tccrun.c
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tccrun.c
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/*
* TCC - Tiny C Compiler - Support for -run switch
*
* Copyright (c) 2001-2004 Fabrice Bellard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "tcc.h"
/* only native compiler supports -run */
#ifdef TCC_IS_NATIVE
typedef struct rt_context
{
#ifdef CONFIG_TCC_BACKTRACE
/* --> tccelf.c:tcc_add_btstub wants those below in that order: */
union {
struct {
Stab_Sym *stab_sym, *stab_sym_end;
char *stab_str;
};
struct {
unsigned char *dwarf_line, *dwarf_line_end, *dwarf_line_str;
};
};
addr_t dwarf;
ElfW(Sym) *esym_start, *esym_end;
char *elf_str;
addr_t prog_base;
void *bounds_start;
struct rt_context *next;
/* <-- */
int num_callers;
addr_t ip, fp, sp;
void *top_func;
#endif
jmp_buf jb;
int do_jmp;
# define NR_AT_EXIT 32
int nr_exit;
void *exitfunc[NR_AT_EXIT];
void *exitarg[NR_AT_EXIT];
} rt_context;
static rt_context g_rtctxt;
static void rt_exit(int code)
{
rt_context *rc = &g_rtctxt;
if (rc->do_jmp)
longjmp(rc->jb, code ? code : 256);
exit(code);
}
#ifdef CONFIG_TCC_BACKTRACE
static void set_exception_handler(void);
static int _rt_error(void *fp, void *ip, const char *fmt, va_list ap);
#endif /* CONFIG_TCC_BACKTRACE */
/* defined when included from lib/bt-exe.c */
#ifndef CONFIG_TCC_BACKTRACE_ONLY
#ifndef _WIN32
# include <sys/mman.h>
#endif
static int set_pages_executable(TCCState *s1, int mode, void *ptr, unsigned long length);
static int tcc_relocate_ex(TCCState *s1, void *ptr, addr_t ptr_diff);
#ifdef _WIN64
static void *win64_add_function_table(TCCState *s1);
static void win64_del_function_table(void *);
#endif
/* ------------------------------------------------------------- */
/* Do all relocations (needed before using tcc_get_symbol())
Returns -1 on error. */
LIBTCCAPI int tcc_relocate(TCCState *s1, void *ptr)
{
int size;
addr_t ptr_diff = 0;
if (TCC_RELOCATE_AUTO != ptr)
return tcc_relocate_ex(s1, ptr, 0);
size = tcc_relocate_ex(s1, NULL, 0);
if (size < 0)
return -1;
#ifdef HAVE_SELINUX
{
/* Using mmap instead of malloc */
void *prx;
char tmpfname[] = "/tmp/.tccrunXXXXXX";
int fd = mkstemp(tmpfname);
unlink(tmpfname);
ftruncate(fd, size);
size = (size + (PAGESIZE-1)) & ~(PAGESIZE-1);
ptr = mmap(NULL, size * 2, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
/* mmap RX memory at a fixed distance */
prx = mmap((char*)ptr + size, size, PROT_READ|PROT_EXEC, MAP_SHARED|MAP_FIXED, fd, 0);
close(fd);
if (ptr == MAP_FAILED || prx == MAP_FAILED)
return tcc_error_noabort("tccrun: could not map memory");
ptr_diff = (char*)prx - (char*)ptr;
//printf("map %p %p %p\n", ptr, prx, (void*)ptr_diff);
}
#else
ptr = tcc_malloc(size);
#endif
if (tcc_relocate_ex(s1, ptr, ptr_diff))
return -1;
dynarray_add(&s1->runtime_mem, &s1->nb_runtime_mem, (void*)(addr_t)size);
dynarray_add(&s1->runtime_mem, &s1->nb_runtime_mem, ptr);
return 0;
}
ST_FUNC void tcc_run_free(TCCState *s1)
{
int i;
for (i = 0; i < s1->nb_runtime_mem; i += 2) {
unsigned size = (unsigned)(addr_t)s1->runtime_mem[i];
void *ptr = s1->runtime_mem[i+1];
#ifdef HAVE_SELINUX
munmap(ptr, size * 2);
#else
/* unprotect memory to make it usable for malloc again */
set_pages_executable(s1, 2, ptr, size);
#ifdef _WIN64
win64_del_function_table(*(void**)ptr);
#endif
tcc_free(ptr);
#endif
}
tcc_free(s1->runtime_mem);
}
static void run_cdtors(TCCState *s1, const char *start, const char *end,
int argc, char **argv, char **envp)
{
void **a = (void **)get_sym_addr(s1, start, 0, 0);
void **b = (void **)get_sym_addr(s1, end, 0, 0);
while (a != b)
((void(*)(int, char **, char **))*a++)(argc, argv, envp);
}
static void run_on_exit(int ret)
{
rt_context *rc = &g_rtctxt;
int n = rc->nr_exit;
while (n)
--n, ((void(*)(int,void*))rc->exitfunc[n])(ret, rc->exitarg[n]);
}
static int rt_on_exit(void *function, void *arg)
{
rt_context *rc = &g_rtctxt;
if (rc->nr_exit < NR_AT_EXIT) {
rc->exitfunc[rc->nr_exit] = function;
rc->exitarg[rc->nr_exit++] = arg;
return 0;
}
return 1;
}
static int rt_atexit(void *function)
{
return rt_on_exit(function, NULL);
}
/* launch the compiled program with the given arguments */
LIBTCCAPI int tcc_run(TCCState *s1, int argc, char **argv)
{
int (*prog_main)(int, char **, char **), ret;
rt_context *rc = &g_rtctxt;
#if defined(__APPLE__) || defined(__FreeBSD__)
char **envp = NULL;
#elif defined(__OpenBSD__) || defined(__NetBSD__)
extern char **environ;
char **envp = environ;
#else
char **envp = environ;
#endif
s1->runtime_main = s1->nostdlib ? "_start" : "main";
if ((s1->dflag & 16) && (addr_t)-1 == get_sym_addr(s1, s1->runtime_main, 0, 1))
return 0;
tcc_add_symbol(s1, "exit", rt_exit);
tcc_add_symbol(s1, "atexit", rt_atexit);
tcc_add_symbol(s1, "on_exit", rt_on_exit);
if (tcc_relocate(s1, TCC_RELOCATE_AUTO) < 0)
return -1;
prog_main = (void*)get_sym_addr(s1, s1->runtime_main, 1, 1);
if ((addr_t)-1 == (addr_t)prog_main)
return -1;
memset(rc, 0, sizeof *rc);
rc->do_jmp = 1;
#ifdef CONFIG_TCC_BACKTRACE
if (s1->do_debug) {
void *p;
if (s1->dwarf) {
rc->dwarf_line = dwarf_line_section->data;
rc->dwarf_line_end = dwarf_line_section->data + dwarf_line_section->data_offset;
if (dwarf_line_str_section)
rc->dwarf_line_str = dwarf_line_str_section->data;
}
else
{
rc->stab_sym = (Stab_Sym *)stab_section->data;
rc->stab_sym_end = (Stab_Sym *)(stab_section->data + stab_section->data_offset);
rc->stab_str = (char *)stab_section->link->data;
}
rc->dwarf = s1->dwarf;
rc->esym_start = (ElfW(Sym) *)(symtab_section->data);
rc->esym_end = (ElfW(Sym) *)(symtab_section->data + symtab_section->data_offset);
rc->elf_str = (char *)symtab_section->link->data;
#if PTR_SIZE == 8
rc->prog_base = text_section->sh_addr & 0xffffffff00000000ULL;
#if defined TCC_TARGET_MACHO
if (s1->dwarf)
rc->prog_base = (addr_t) -1;
#else
#endif
#endif
rc->top_func = tcc_get_symbol(s1, "main");
rc->num_callers = s1->rt_num_callers;
if ((p = tcc_get_symbol(s1, "__rt_error")))
*(void**)p = _rt_error;
#ifdef CONFIG_TCC_BCHECK
if (s1->do_bounds_check) {
rc->bounds_start = (void*)bounds_section->sh_addr;
if ((p = tcc_get_symbol(s1, "__bound_init")))
((void(*)(void*,int))p)(rc->bounds_start, 1);
}
#endif
set_exception_handler();
}
#endif
errno = 0; /* clean errno value */
fflush(stdout);
fflush(stderr);
/* These aren't C symbols, so don't need leading underscore handling. */
run_cdtors(s1, "__init_array_start", "__init_array_end", argc, argv, envp);
if (!(ret = setjmp(rc->jb)))
ret = prog_main(argc, argv, envp);
run_cdtors(s1, "__fini_array_start", "__fini_array_end", 0, NULL, NULL);
run_on_exit(ret);
if (s1->dflag & 16 && ret) /* tcc -dt -run ... */
fprintf(s1->ppfp, "[returns %d]\n", ret), fflush(s1->ppfp);
return ret;
}
#define DEBUG_RUNMEN 0
/* enable rx/ro/rw permissions */
#define CONFIG_RUNMEM_RO 1
#if CONFIG_RUNMEM_RO
# define PAGE_ALIGN PAGESIZE
#elif defined TCC_TARGET_I386 || defined TCC_TARGET_X86_64
/* To avoid that x86 processors would reload cached instructions
each time when data is written in the near, we need to make
sure that code and data do not share the same 64 byte unit */
# define PAGE_ALIGN 64
#else
# define PAGE_ALIGN 1
#endif
/* relocate code. Return -1 on error, required size if ptr is NULL,
otherwise copy code into buffer passed by the caller */
static int tcc_relocate_ex(TCCState *s1, void *ptr, addr_t ptr_diff)
{
Section *s;
unsigned offset, length, align, max_align, i, k, f;
unsigned n, copy;
addr_t mem, addr;
if (NULL == ptr) {
s1->nb_errors = 0;
#ifdef TCC_TARGET_PE
pe_output_file(s1, NULL);
#else
tcc_add_runtime(s1);
resolve_common_syms(s1);
build_got_entries(s1, 0);
#endif
if (s1->nb_errors)
return -1;
}
offset = max_align = 0, mem = (addr_t)ptr;
#ifdef _WIN64
offset += sizeof (void*); /* space for function_table pointer */
#endif
copy = 0;
redo:
for (k = 0; k < 3; ++k) { /* 0:rx, 1:ro, 2:rw sections */
n = 0; addr = 0;
for(i = 1; i < s1->nb_sections; i++) {
static const char shf[] = {
SHF_ALLOC|SHF_EXECINSTR, SHF_ALLOC, SHF_ALLOC|SHF_WRITE
};
s = s1->sections[i];
if (shf[k] != (s->sh_flags & (SHF_ALLOC|SHF_WRITE|SHF_EXECINSTR)))
continue;
length = s->data_offset;
if (copy) {
if (addr == 0)
addr = s->sh_addr;
n = (s->sh_addr - addr) + length;
ptr = (void*)s->sh_addr;
if (k == 0)
ptr = (void*)(s->sh_addr - ptr_diff);
if (NULL == s->data || s->sh_type == SHT_NOBITS)
memset(ptr, 0, length);
else
memcpy(ptr, s->data, length);
#ifdef _WIN64
if (s == s1->uw_pdata)
*(void**)mem = win64_add_function_table(s1);
#endif
if (s->data) {
tcc_free(s->data);
s->data = NULL;
s->data_allocated = 0;
}
s->data_offset = 0;
continue;
}
align = s->sh_addralign - 1;
if (++n == 1 && align < (PAGE_ALIGN - 1))
align = (PAGE_ALIGN - 1);
if (max_align < align)
max_align = align;
addr = k ? mem : mem + ptr_diff;
offset += -(addr + offset) & align;
s->sh_addr = mem ? addr + offset : 0;
offset += length;
#if DEBUG_RUNMEN
if (mem)
printf("%d: %-16s %p len %04x align %04x\n",
k, s->name, (void*)s->sh_addr, length, align + 1);
#endif
}
if (copy) { /* set permissions */
if (k == 0 && ptr_diff)
continue; /* not with HAVE_SELINUX */
f = k;
#if !CONFIG_RUNMEM_RO
if (f != 0)
continue;
f = 3; /* change only SHF_EXECINSTR to rwx */
#endif
#if DEBUG_RUNMEN
printf("protect %d %p %04x\n", f, (void*)addr, n);
#endif
if (n) {
if (set_pages_executable(s1, f, (void*)addr, n))
return -1;
}
}
}
if (copy)
return 0;
/* relocate symbols */
relocate_syms(s1, s1->symtab, !(s1->nostdlib));
if (s1->nb_errors)
return -1;
if (0 == mem)
return offset + max_align;
#ifdef TCC_TARGET_PE
s1->pe_imagebase = mem;
#endif
/* relocate sections */
#ifndef TCC_TARGET_PE
relocate_plt(s1);
#endif
relocate_sections(s1);
copy = 1;
goto redo;
}
/* ------------------------------------------------------------- */
/* allow to run code in memory */
static int set_pages_executable(TCCState *s1, int mode, void *ptr, unsigned long length)
{
#ifdef _WIN32
static const unsigned char protect[] = {
PAGE_EXECUTE_READ,
PAGE_READONLY,
PAGE_READWRITE,
PAGE_EXECUTE_READWRITE
};
DWORD old;
if (!VirtualProtect(ptr, length, protect[mode], &old))
return -1;
return 0;
#else
static const unsigned char protect[] = {
PROT_READ | PROT_EXEC,
PROT_READ,
PROT_READ | PROT_WRITE,
PROT_READ | PROT_WRITE | PROT_EXEC
};
addr_t start, end;
start = (addr_t)ptr & ~(PAGESIZE - 1);
end = (addr_t)ptr + length;
end = (end + PAGESIZE - 1) & ~(PAGESIZE - 1);
if (mprotect((void *)start, end - start, protect[mode]))
return tcc_error_noabort("mprotect failed: did you mean to configure --with-selinux?");
/* XXX: BSD sometimes dump core with bad system call */
# if (defined TCC_TARGET_ARM && !TARGETOS_BSD) || defined TCC_TARGET_ARM64
if (mode == 0 || mode == 3) {
void __clear_cache(void *beginning, void *end);
__clear_cache(ptr, (char *)ptr + length);
}
# endif
return 0;
#endif
}
#ifdef _WIN64
static void *win64_add_function_table(TCCState *s1)
{
void *p = NULL;
if (s1->uw_pdata) {
p = (void*)s1->uw_pdata->sh_addr;
RtlAddFunctionTable(
(RUNTIME_FUNCTION*)p,
s1->uw_pdata->data_offset / sizeof (RUNTIME_FUNCTION),
s1->pe_imagebase
);
s1->uw_pdata = NULL;
}
return p;
}
static void win64_del_function_table(void *p)
{
if (p) {
RtlDeleteFunctionTable((RUNTIME_FUNCTION*)p);
}
}
#endif
#endif //ndef CONFIG_TCC_BACKTRACE_ONLY
/* ------------------------------------------------------------- */
#ifdef CONFIG_TCC_BACKTRACE
static int rt_vprintf(const char *fmt, va_list ap)
{
int ret = vfprintf(stderr, fmt, ap);
fflush(stderr);
return ret;
}
static int rt_printf(const char *fmt, ...)
{
va_list ap;
int r;
va_start(ap, fmt);
r = rt_vprintf(fmt, ap);
va_end(ap);
return r;
}
static char *rt_elfsym(rt_context *rc, addr_t wanted_pc, addr_t *func_addr)
{
ElfW(Sym) *esym;
for (esym = rc->esym_start + 1; esym < rc->esym_end; ++esym) {
int type = ELFW(ST_TYPE)(esym->st_info);
if ((type == STT_FUNC || type == STT_GNU_IFUNC)
&& wanted_pc >= esym->st_value
&& wanted_pc < esym->st_value + esym->st_size) {
*func_addr = esym->st_value;
return rc->elf_str + esym->st_name;
}
}
return NULL;
}
/* print the position in the source file of PC value 'pc' by reading
the stabs debug information */
static addr_t rt_printline (rt_context *rc, addr_t wanted_pc,
const char *msg, const char *skip)
{
char func_name[128];
addr_t func_addr, last_pc, pc;
const char *incl_files[INCLUDE_STACK_SIZE];
int incl_index, last_incl_index, len, last_line_num, i;
const char *str, *p;
Stab_Sym *sym;
next:
func_name[0] = '\0';
func_addr = 0;
incl_index = 0;
last_pc = (addr_t)-1;
last_line_num = 1;
last_incl_index = 0;
for (sym = rc->stab_sym + 1; sym < rc->stab_sym_end; ++sym) {
str = rc->stab_str + sym->n_strx;
pc = sym->n_value;
switch(sym->n_type) {
case N_SLINE:
if (func_addr)
goto rel_pc;
case N_SO:
case N_SOL:
goto abs_pc;
case N_FUN:
if (sym->n_strx == 0) /* end of function */
goto rel_pc;
abs_pc:
#if PTR_SIZE == 8
/* Stab_Sym.n_value is only 32bits */
pc += rc->prog_base;
#endif
goto check_pc;
rel_pc:
pc += func_addr;
check_pc:
if (pc >= wanted_pc && wanted_pc >= last_pc)
goto found;
break;
}
switch(sym->n_type) {
/* function start or end */
case N_FUN:
if (sym->n_strx == 0)
goto reset_func;
p = strchr(str, ':');
if (0 == p || (len = p - str + 1, len > sizeof func_name))
len = sizeof func_name;
pstrcpy(func_name, len, str);
func_addr = pc;
break;
/* line number info */
case N_SLINE:
last_pc = pc;
last_line_num = sym->n_desc;
last_incl_index = incl_index;
break;
/* include files */
case N_BINCL:
if (incl_index < INCLUDE_STACK_SIZE)
incl_files[incl_index++] = str;
break;
case N_EINCL:
if (incl_index > 1)
incl_index--;
break;
/* start/end of translation unit */
case N_SO:
incl_index = 0;
if (sym->n_strx) {
/* do not add path */
len = strlen(str);
if (len > 0 && str[len - 1] != '/')
incl_files[incl_index++] = str;
}
reset_func:
func_name[0] = '\0';
func_addr = 0;
last_pc = (addr_t)-1;
break;
/* alternative file name (from #line or #include directives) */
case N_SOL:
if (incl_index)
incl_files[incl_index-1] = str;
break;
}
}
func_name[0] = '\0';
func_addr = 0;
last_incl_index = 0;
/* we try symtab symbols (no line number info) */
p = rt_elfsym(rc, wanted_pc, &func_addr);
if (p) {
pstrcpy(func_name, sizeof func_name, p);
goto found;
}
if ((rc = rc->next))
goto next;
found:
i = last_incl_index;
if (i > 0) {
str = incl_files[--i];
if (skip[0] && strstr(str, skip))
return (addr_t)-1;
rt_printf("%s:%d: ", str, last_line_num);
} else
rt_printf("%08llx : ", (long long)wanted_pc);
rt_printf("%s %s", msg, func_name[0] ? func_name : "???");
#if 0
if (--i >= 0) {
rt_printf(" (included from ");
for (;;) {
rt_printf("%s", incl_files[i]);
if (--i < 0)
break;
rt_printf(", ");
}
rt_printf(")");
}
#endif
return func_addr;
}
/* ------------------------------------------------------------- */
/* rt_printline - dwarf version */
#define MAX_128 ((8 * sizeof (long long) + 6) / 7)
#define DIR_TABLE_SIZE (64)
#define FILE_TABLE_SIZE (512)
#define dwarf_read_1(ln,end) \
((ln) < (end) ? *(ln)++ : 0)
#define dwarf_read_2(ln,end) \
((ln) + 2 < (end) ? (ln) += 2, read16le((ln) - 2) : 0)
#define dwarf_read_4(ln,end) \
((ln) + 4 < (end) ? (ln) += 4, read32le((ln) - 4) : 0)
#define dwarf_read_8(ln,end) \
((ln) + 8 < (end) ? (ln) += 8, read64le((ln) - 8) : 0)
#define dwarf_ignore_type(ln, end) /* timestamp/size/md5/... */ \
switch (entry_format[j].form) { \
case DW_FORM_data1: (ln) += 1; break; \
case DW_FORM_data2: (ln) += 2; break; \
case DW_FORM_data4: (ln) += 3; break; \
case DW_FORM_data8: (ln) += 8; break; \
case DW_FORM_data16: (ln) += 16; break; \
case DW_FORM_udata: dwarf_read_uleb128(&(ln), (end)); break; \
default: goto next_line; \
}
static unsigned long long
dwarf_read_uleb128(unsigned char **ln, unsigned char *end)
{
unsigned char *cp = *ln;
unsigned long long retval = 0;
int i;
for (i = 0; i < MAX_128; i++) {
unsigned long long byte = dwarf_read_1(cp, end);
retval |= (byte & 0x7f) << (i * 7);
if ((byte & 0x80) == 0)
break;
}
*ln = cp;
return retval;
}
static long long
dwarf_read_sleb128(unsigned char **ln, unsigned char *end)
{
unsigned char *cp = *ln;
long long retval = 0;
int i;
for (i = 0; i < MAX_128; i++) {
unsigned long long byte = dwarf_read_1(cp, end);
retval |= (byte & 0x7f) << (i * 7);
if ((byte & 0x80) == 0) {
if ((byte & 0x40) && (i + 1) * 7 < 64)
retval |= -1LL << ((i + 1) * 7);
break;
}
}
*ln = cp;
return retval;
}
static addr_t rt_printline_dwarf (rt_context *rc, addr_t wanted_pc,
const char *msg, const char *skip)
{
unsigned char *ln;
unsigned char *cp;
unsigned char *end;
unsigned char *opcode_length;
unsigned long long size;
unsigned int length;
unsigned char version;
unsigned int min_insn_length;
unsigned int max_ops_per_insn;
int line_base;
unsigned int line_range;
unsigned int opcode_base;
unsigned int opindex;
unsigned int col;
unsigned int i;
unsigned int j;
unsigned int len;
unsigned long long value;
struct {
unsigned int type;
unsigned int form;
} entry_format[256];
unsigned int dir_size;
#if 0
char *dirs[DIR_TABLE_SIZE];
#endif
unsigned int filename_size;
struct dwarf_filename_struct {
unsigned int dir_entry;
char *name;
} filename_table[FILE_TABLE_SIZE];
addr_t last_pc;
addr_t pc;
addr_t func_addr;
int line;
char *filename;
char *function;
next:
ln = rc->dwarf_line;
while (ln < rc->dwarf_line_end) {
dir_size = 0;
filename_size = 0;
last_pc = 0;
pc = 0;
func_addr = 0;
line = 1;
filename = NULL;
function = NULL;
length = 4;
size = dwarf_read_4(ln, rc->dwarf_line_end);
if (size == 0xffffffffu) // dwarf 64
length = 8, size = dwarf_read_8(ln, rc->dwarf_line_end);
end = ln + size;
if (end < ln || end > rc->dwarf_line_end)
break;
version = dwarf_read_2(ln, end);
if (version >= 5)
ln += length + 2; // address size, segment selector, prologue Length
else
ln += length; // prologue Length
min_insn_length = dwarf_read_1(ln, end);
if (version >= 4)
max_ops_per_insn = dwarf_read_1(ln, end);
else
max_ops_per_insn = 1;
ln++; // Initial value of 'is_stmt'
line_base = dwarf_read_1(ln, end);
line_base |= line_base >= 0x80 ? ~0xff : 0;
line_range = dwarf_read_1(ln, end);
opcode_base = dwarf_read_1(ln, end);
opcode_length = ln;
ln += opcode_base - 1;
opindex = 0;
if (version >= 5) {
col = dwarf_read_1(ln, end);
for (i = 0; i < col; i++) {
entry_format[i].type = dwarf_read_uleb128(&ln, end);
entry_format[i].form = dwarf_read_uleb128(&ln, end);
}
dir_size = dwarf_read_uleb128(&ln, end);
for (i = 0; i < dir_size; i++) {
for (j = 0; j < col; j++) {
if (entry_format[j].type == DW_LNCT_path) {
if (entry_format[j].form != DW_FORM_line_strp)
goto next_line;
#if 0
value = length == 4 ? dwarf_read_4(ln, end)
: dwarf_read_8(ln, end);
if (i < DIR_TABLE_SIZE)
dirs[i] = (char *)rc->dwarf_line_str + value;
#else
length == 4 ? dwarf_read_4(ln, end)
: dwarf_read_8(ln, end);
#endif
}
else
dwarf_ignore_type(ln, end);
}
}
col = dwarf_read_1(ln, end);
for (i = 0; i < col; i++) {
entry_format[i].type = dwarf_read_uleb128(&ln, end);
entry_format[i].form = dwarf_read_uleb128(&ln, end);
}
filename_size = dwarf_read_uleb128(&ln, end);
for (i = 0; i < filename_size; i++)
for (j = 0; j < col; j++) {
if (entry_format[j].type == DW_LNCT_path) {
if (entry_format[j].form != DW_FORM_line_strp)
goto next_line;
value = length == 4 ? dwarf_read_4(ln, end)
: dwarf_read_8(ln, end);
if (i < FILE_TABLE_SIZE)
filename_table[i].name =
(char *)rc->dwarf_line_str + value;
}
else if (entry_format[j].type == DW_LNCT_directory_index) {
switch (entry_format[j].form) {
case DW_FORM_data1: value = dwarf_read_1(ln, end); break;
case DW_FORM_data2: value = dwarf_read_2(ln, end); break;
case DW_FORM_data4: value = dwarf_read_4(ln, end); break;
case DW_FORM_udata: value = dwarf_read_uleb128(&ln, end); break;
default: goto next_line;
}
if (i < FILE_TABLE_SIZE)
filename_table[i].dir_entry = value;
}
else
dwarf_ignore_type(ln, end);
}
}
else {
while ((dwarf_read_1(ln, end))) {
#if 0
if (++dir_size < DIR_TABLE_SIZE)
dirs[dir_size - 1] = (char *)ln - 1;
#endif
while (dwarf_read_1(ln, end)) {}
}
while ((dwarf_read_1(ln, end))) {
if (++filename_size < FILE_TABLE_SIZE) {
filename_table[filename_size - 1].name = (char *)ln - 1;
while (dwarf_read_1(ln, end)) {}
filename_table[filename_size - 1].dir_entry =
dwarf_read_uleb128(&ln, end);
}
else {
while (dwarf_read_1(ln, end)) {}
dwarf_read_uleb128(&ln, end);
}
dwarf_read_uleb128(&ln, end); // time
dwarf_read_uleb128(&ln, end); // size
}
}
if (filename_size >= 1)
filename = filename_table[0].name;
while (ln < end) {
last_pc = pc;
i = dwarf_read_1(ln, end);
if (i >= opcode_base) {
if (max_ops_per_insn == 1)
pc += ((i - opcode_base) / line_range) * min_insn_length;
else {
pc += (opindex + (i - opcode_base) / line_range) /
max_ops_per_insn * min_insn_length;
opindex = (opindex + (i - opcode_base) / line_range) %
max_ops_per_insn;
}
i = (int)((i - opcode_base) % line_range) + line_base;
check_pc:
if (pc >= wanted_pc && wanted_pc >= last_pc)
goto found;
line += i;
}
else {
switch (i) {
case 0:
len = dwarf_read_uleb128(&ln, end);
cp = ln;
ln += len;
if (len == 0)
goto next_line;
switch (dwarf_read_1(cp, end)) {
case DW_LNE_end_sequence:
break;
case DW_LNE_set_address:
#if PTR_SIZE == 4
pc = dwarf_read_4(cp, end);
#else
pc = dwarf_read_8(cp, end);
#endif
#if defined TCC_TARGET_MACHO
if (rc->prog_base != (addr_t) -1)
pc += rc->prog_base;
#endif
opindex = 0;
break;
case DW_LNE_define_file: /* deprecated */
if (++filename_size < FILE_TABLE_SIZE) {
filename_table[filename_size - 1].name = (char *)ln - 1;
while (dwarf_read_1(ln, end)) {}
filename_table[filename_size - 1].dir_entry =
dwarf_read_uleb128(&ln, end);
}
else {
while (dwarf_read_1(ln, end)) {}
dwarf_read_uleb128(&ln, end);
}
dwarf_read_uleb128(&ln, end); // time
dwarf_read_uleb128(&ln, end); // size
break;
case DW_LNE_hi_user - 1:
function = (char *)cp;
func_addr = pc;
break;
default:
break;
}
break;
case DW_LNS_advance_pc:
if (max_ops_per_insn == 1)
pc += dwarf_read_uleb128(&ln, end) * min_insn_length;
else {
unsigned long long off = dwarf_read_uleb128(&ln, end);
pc += (opindex + off) / max_ops_per_insn *
min_insn_length;
opindex = (opindex + off) % max_ops_per_insn;
}
i = 0;
goto check_pc;
case DW_LNS_advance_line:
line += dwarf_read_sleb128(&ln, end);
break;
case DW_LNS_set_file:
i = dwarf_read_uleb128(&ln, end);
i -= i > 0 && version < 5;
if (i < FILE_TABLE_SIZE && i < filename_size)
filename = filename_table[i].name;
break;
case DW_LNS_const_add_pc:
if (max_ops_per_insn == 1)
pc += ((255 - opcode_base) / line_range) * min_insn_length;
else {
unsigned int off = (255 - opcode_base) / line_range;
pc += ((opindex + off) / max_ops_per_insn) *
min_insn_length;
opindex = (opindex + off) % max_ops_per_insn;
}
i = 0;
goto check_pc;
case DW_LNS_fixed_advance_pc:
i = dwarf_read_2(ln, end);
pc += i;
opindex = 0;
i = 0;
goto check_pc;
default:
for (j = 0; j < opcode_length[i - 1]; j++)
dwarf_read_uleb128 (&ln, end);
break;
}
}
}
next_line:
ln = end;
}
filename = NULL;
func_addr = 0;
/* we try symtab symbols (no line number info) */
function = rt_elfsym(rc, wanted_pc, &func_addr);
if (function)
goto found;
if ((rc = rc->next))
goto next;
found:
if (filename) {
if (skip[0] && strstr(filename, skip))
return (addr_t)-1;
rt_printf("%s:%d: ", filename, line);
}
else
rt_printf("0x%08llx : ", (long long)wanted_pc);
rt_printf("%s %s", msg, function ? function : "???");
return (addr_t)func_addr;
}
/* ------------------------------------------------------------- */