| |
| /*--------------------------------------------------------------------*/ |
| /*--- Take snapshots of client stacks. m_stacktrace.c ---*/ |
| /*--------------------------------------------------------------------*/ |
| |
| /* |
| This file is part of Valgrind, a dynamic binary instrumentation |
| framework. |
| |
| Copyright (C) 2000-2005 Julian Seward |
| jseward@acm.org |
| |
| This program 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 2 of the |
| License, or (at your option) any later version. |
| |
| This program 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. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307, USA. |
| |
| The GNU General Public License is contained in the file COPYING. |
| */ |
| |
| #include "pub_core_basics.h" |
| #include "pub_core_threadstate.h" |
| #include "pub_core_aspacemgr.h" |
| #include "pub_core_libcbase.h" |
| #include "pub_core_libcassert.h" |
| #include "pub_core_libcprint.h" |
| #include "pub_core_machine.h" |
| #include "pub_core_options.h" |
| #include "pub_core_profile.h" |
| #include "pub_core_stacktrace.h" |
| #include "pub_core_trampoline.h" |
| |
| /*------------------------------------------------------------*/ |
| /*--- Exported functions. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| // Stack frame layout and linkage |
| #if defined(VGA_x86) |
| # define FIRST_STACK_FRAME(ebp) (ebp) |
| # define STACK_FRAME_RET(ebp) (((UWord*)ebp)[1]) |
| # define STACK_FRAME_NEXT(ebp) (((UWord*)ebp)[0]) |
| #elif defined(VGA_amd64) |
| # define FIRST_STACK_FRAME(rbp) (rbp) |
| # define STACK_FRAME_RET(rbp) (((UWord*)rbp)[1]) |
| # define STACK_FRAME_NEXT(rbp) (((UWord*)rbp)[0]) |
| #else |
| # error Unknown platform |
| #endif |
| |
| /* Take a snapshot of the client's stack, putting the up to 'n_ips' IPs |
| into 'ips'. In order to be thread-safe, we pass in the thread's IP |
| and FP. Returns number of IPs put in 'ips'. */ |
| UInt VG_(get_StackTrace2) ( Addr* ips, UInt n_ips, |
| Addr ip, Addr sp, Addr fp, |
| Addr fp_min, Addr fp_max_orig ) |
| { |
| static const Bool debug = False; |
| Int i; |
| Addr fp_max; |
| UInt n_found = 0; |
| |
| VGP_PUSHCC(VgpExeContext); |
| |
| /* First snaffle IPs from the client's stack into ips[0 .. n_ips-1], |
| putting zeroes in when the trail goes cold, which we guess to be when |
| FP is not a reasonable stack location. We also assert that FP |
| increases down the chain. */ |
| |
| // Gives shorter stack trace for tests/badjump.c |
| // JRS 2002-aug-16: I don't think this is a big deal; looks ok for |
| // most "normal" backtraces. |
| // NJN 2002-sep-05: traces for pthreaded programs are particularly bad. |
| |
| // JRS 2002-sep-17: hack, to round up fp_max to the end of the |
| // current page, at least. Dunno if it helps. |
| // NJN 2002-sep-17: seems to -- stack traces look like 1.0.X again |
| fp_max = (fp_max_orig + VKI_PAGE_SIZE - 1) & ~(VKI_PAGE_SIZE - 1); |
| fp_max -= sizeof(Addr); |
| |
| if (debug) |
| VG_(printf)("n_ips=%d fp_min=%p fp_max_orig=%p, fp_max=%p ip=%p fp=%p\n", |
| n_ips, fp_min, fp_max_orig, fp_max, ip, fp); |
| |
| /* Assertion broken before main() is reached in pthreaded programs; the |
| * offending stack traces only have one item. --njn, 2002-aug-16 */ |
| /* vg_assert(fp_min <= fp_max);*/ |
| |
| ips[0] = ip; |
| i = 1; |
| |
| if (fp_min + VG_(clo_max_stackframe) <= fp_max) { |
| /* If the stack is ridiculously big, don't poke around ... but |
| don't bomb out either. Needed to make John Regehr's |
| user-space threads package work. JRS 20021001 */ |
| } else { |
| |
| // XXX: I think this line is needed for PPC to work, but I'm not |
| // certain, so I'm commenting it out for the moment. |
| //fp = FIRST_STACK_FRAME(fp) |
| |
| while (True) { |
| |
| if (i >= n_ips) |
| break; |
| |
| /* Try to derive a new (ip,sp,fp) triple from the current |
| set. */ |
| |
| /* First off, see if there is any CFI info to hand which can |
| be used. */ |
| if ( VG_(use_CFI_info)( &ip, &sp, &fp, fp_min, fp_max ) ) { |
| ips[i++] = ip; |
| if (debug) |
| VG_(printf)(" ipsC[%d]=%08p\n", i-1, ips[i-1]); |
| continue; |
| } |
| |
| /* If VG_(use_CFI_info) fails, it won't modify ip/sp/fp, so |
| we can safely try the old-fashioned method. */ |
| /* This bit is supposed to deal with frames resulting from |
| functions which begin "pushl% ebp ; movl %esp, %ebp" (x86) |
| or "pushq %rbp ; movq %rsp, %rbp" (amd64). Unfortunately, |
| since we can't (easily) look at the insns at the start of |
| the fn, like GDB does, there's no reliable way to tell. |
| Hence the hack of first trying out CFI, and if that fails, |
| then use this as a fallback. */ |
| if (fp_min <= fp && fp <= fp_max) { |
| /* fp looks sane, so use it. */ |
| ip = STACK_FRAME_RET(fp); |
| sp = fp + sizeof(Addr) /*saved %ebp/%rbp*/ |
| + sizeof(Addr) /*ra*/; |
| fp = STACK_FRAME_NEXT(fp); |
| ips[i++] = ip; |
| if (debug) |
| VG_(printf)(" ipsF[%d]=%08p\n", i-1, ips[i-1]); |
| continue; |
| } |
| |
| /* No luck there. We have to give up. */ |
| break; |
| } |
| |
| } |
| n_found = i; |
| |
| /* Put zeroes in the rest. */ |
| for (; i < n_ips; i++) { |
| ips[i] = 0; |
| } |
| VGP_POPCC(VgpExeContext); |
| |
| return n_found; |
| } |
| |
| UInt VG_(get_StackTrace) ( ThreadId tid, StackTrace ips, UInt n_ips ) |
| { |
| /* thread in thread table */ |
| Addr ip = VG_(get_IP)(tid); |
| Addr fp = VG_(get_FP)(tid); |
| Addr sp = VG_(get_SP)(tid); |
| Addr stack_highest_word = VG_(threads)[tid].client_stack_highest_word; |
| |
| #if defined(VGP_x86_linux) |
| /* Nasty little hack to deal with sysinfo syscalls - if libc is |
| using the sysinfo page for syscalls (the TLS version does), then |
| ip will always appear to be in that page when doing a syscall, |
| not the actual libc function doing the syscall. This check sees |
| if IP is within the syscall code, and pops the return address |
| off the stack so that ip is placed within the library function |
| calling the syscall. This makes stack backtraces much more |
| useful. */ |
| if (ip >= VG_(client_trampoline_code)+VG_(tramp_syscall_offset) && |
| ip < VG_(client_trampoline_code)+VG_(trampoline_code_length) && |
| VG_(is_addressable)(sp, sizeof(Addr), VKI_PROT_READ)) { |
| ip = *(Addr *)sp; |
| sp += sizeof(Addr); |
| } |
| #endif |
| if (0) |
| VG_(printf)("tid %d: stack_highest=%p ip=%p sp=%p fp=%p\n", |
| tid, stack_highest_word, ip, sp, fp); |
| |
| return VG_(get_StackTrace2)(ips, n_ips, ip, sp, fp, sp, stack_highest_word); |
| } |
| |
| static void printIpDesc(UInt n, Addr ip) |
| { |
| #define BUF_LEN 4096 |
| |
| static UChar buf[BUF_LEN]; |
| |
| VG_(describe_IP)(ip, buf, BUF_LEN); |
| |
| if (VG_(clo_xml)) { |
| VG_(message)(Vg_UserMsg, " %s", buf); |
| } else { |
| VG_(message)(Vg_UserMsg, " %s %s", ( n == 0 ? "at" : "by" ), buf); |
| } |
| } |
| |
| /* Print a StackTrace. */ |
| void VG_(pp_StackTrace) ( StackTrace ips, UInt n_ips ) |
| { |
| vg_assert( n_ips > 0 ); |
| |
| if (VG_(clo_xml)) |
| VG_(message)(Vg_UserMsg, " <stack>"); |
| |
| VG_(apply_StackTrace)( printIpDesc, ips, n_ips ); |
| |
| if (VG_(clo_xml)) |
| VG_(message)(Vg_UserMsg, " </stack>"); |
| } |
| |
| /* Get and immediately print a StackTrace. */ |
| void VG_(get_and_pp_StackTrace) ( ThreadId tid, UInt n_ips ) |
| { |
| Addr ips[n_ips]; |
| VG_(get_StackTrace)(tid, ips, n_ips); |
| VG_(pp_StackTrace) ( ips, n_ips); |
| } |
| |
| |
| void VG_(apply_StackTrace)( void(*action)(UInt n, Addr ip), |
| StackTrace ips, UInt n_ips ) |
| { |
| #define MYBUF_LEN 10 // only needs to be long enough for "main" |
| |
| Bool main_done = False; |
| Char mybuf[MYBUF_LEN]; // ok to stack allocate mybuf[] -- it's tiny |
| Int i = 0; |
| |
| vg_assert(n_ips > 0); |
| do { |
| Addr ip = ips[i]; |
| if (i > 0) |
| ip -= VGA_MIN_INSTR_SZB; // point to calling line |
| |
| // Stop after "main"; if main() is recursive, stop after last main(). |
| if ( ! VG_(clo_show_below_main)) { |
| VG_(get_fnname_nodemangle)( ip, mybuf, MYBUF_LEN ); |
| if ( VG_STREQ("main", mybuf) ) |
| main_done = True; |
| else if (main_done) |
| break; |
| } |
| |
| // Act on the ip |
| action(i, ip); |
| |
| i++; |
| } while (i < n_ips && ips[i] != 0); |
| |
| #undef MYBUF_LEN |
| } |
| |
| |
| /*--------------------------------------------------------------------*/ |
| /*--- end m_stacktrace.c ---*/ |
| /*--------------------------------------------------------------------*/ |