| |
| /*--------------------------------------------------------------------*/ |
| /*--- Take snapshots of client stacks. m_stacktrace.c ---*/ |
| /*--------------------------------------------------------------------*/ |
| |
| /* |
| This file is part of Valgrind, a dynamic binary instrumentation |
| framework. |
| |
| Copyright (C) 2000-2013 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_vki.h" |
| #include "pub_core_libcsetjmp.h" // to keep _threadstate.h happy |
| #include "pub_core_threadstate.h" |
| #include "pub_core_debuginfo.h" // XXX: circular dependency |
| #include "pub_core_aspacemgr.h" // For VG_(is_addressable)() |
| #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_stacks.h" // VG_(stack_limits) |
| #include "pub_core_stacktrace.h" |
| #include "pub_core_xarray.h" |
| #include "pub_core_clientstate.h" // VG_(client__dl_sysinfo_int80) |
| #include "pub_core_trampoline.h" |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- ---*/ |
| /*--- BEGIN platform-dependent unwinder worker functions ---*/ |
| /*--- ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /* Take a snapshot of the client's stack, putting up to 'max_n_ips' |
| IPs into 'ips'. In order to be thread-safe, we pass in the |
| thread's IP SP, FP if that's meaningful, and LR if that's |
| meaningful. Returns number of IPs put in 'ips'. |
| |
| If you know what the thread ID for this stack is, send that as the |
| first parameter, else send zero. This helps generate better stack |
| traces on ppc64-linux and has no effect on other platforms. |
| */ |
| |
| /* Do frame merging in the _i frames in _ips array of recursive cycles |
| of up to _nframes. The merge is done during stack unwinding |
| (i.e. in platform specific unwinders) to collect as many |
| "interesting" stack traces as possible. */ |
| #define RECURSIVE_MERGE(_nframes,_ips,_i){ \ |
| Int dist; \ |
| for (dist = 1; dist <= _nframes && dist < (Int)_i; dist++) { \ |
| if (_ips[_i-1] == _ips[_i-1-dist]) { \ |
| _i = _i - dist; \ |
| break; \ |
| } \ |
| } \ |
| } |
| |
| |
| /* ------------------------ x86 ------------------------- */ |
| |
| #if defined(VGP_x86_linux) || defined(VGP_x86_darwin) |
| |
| #define N_FP_CF_VERIF 1021 |
| // prime number so that size of fp_CF_verif is just below 4K or 8K |
| // Note that this prime nr differs from the one chosen in |
| // m_debuginfo/debuginfo.c for the cfsi cache : in case we have |
| // a collision here between two IPs, we expect to not (often) have the |
| // same collision in the cfsi cache (and vice-versa). |
| |
| // unwinding with fp chain is ok: |
| #define FPUNWIND 0 |
| // there is no CFI info for this IP: |
| #define NOINFO 1 |
| // Unwind with FP is not ok, must use CF unwind: |
| #define CFUNWIND 2 |
| |
| static Addr fp_CF_verif_cache [N_FP_CF_VERIF]; |
| |
| /* An unwind done by following the fp chain technique can be incorrect |
| as not all frames are respecting the standard bp/sp ABI. |
| The CF information is now generated by default by gcc |
| (as part of the dwarf info). However, unwinding using CF information |
| is significantly slower : a slowdown of 20% has been observed |
| on an helgrind test case. |
| So, by default, the unwinding will be done using the fp chain. |
| But before accepting to unwind an IP with fp_chain, the result |
| of the unwind will be checked with the CF information. |
| This check can give 3 results: |
| FPUNWIND (0): there is CF info, and it gives the same result as fp unwind. |
| => it is assumed that future unwind for this IP can be done |
| with the fast fp chain, without further CF checking |
| NOINFO (1): there is no CF info (so, fp unwind is the only do-able thing) |
| CFUNWIND (2): there is CF info, but unwind result differs. |
| => it is assumed that future unwind for this IP must be done |
| with the CF info. |
| Of course, if each fp unwind implies a check done with a CF unwind, |
| it would just be slower => we cache the check result in an |
| array of checked Addr. |
| The check for an IP will be stored at |
| fp_CF_verif_cache[IP % N_FP_CF_VERIF] as one of: |
| IP ^ FPUNWIND |
| IP ^ NOINFO |
| IP ^ CFUNWIND |
| |
| Note: we can re-use the last (ROUNDDOWN (log (N_FP_CF_VERIF))) bits |
| to store the check result, as they are guaranteed to be non significant |
| in the comparison between 2 IPs stored in fp_CF_verif_cache). |
| In other words, if two IPs are only differing on the last 2 bits, |
| then they will not land in the same cache bucket. |
| */ |
| |
| static UInt fp_CF_verif_generation = 0; |
| // Our cache has to be maintained in sync with the CFI cache. |
| // Each time the CFI cache is changed, its generation will be incremented. |
| // We will clear our cache when our saved generation differs from |
| // the CFI cache generation. |
| |
| UInt VG_(get_StackTrace_wrk) ( ThreadId tid_if_known, |
| /*OUT*/Addr* ips, UInt max_n_ips, |
| /*OUT*/Addr* sps, /*OUT*/Addr* fps, |
| UnwindStartRegs* startRegs, |
| Addr fp_max_orig ) |
| { |
| const Bool do_stats = False; // compute and output some stats regularly. |
| static struct { |
| UInt nr; // nr of stacktraces computed |
| UInt nf; // nr of frames computed |
| UInt Ca; // unwind for which cache indicates CFUnwind must be used. |
| UInt FF; // unwind for which cache indicates FPUnwind can be used. |
| UInt Cf; // unwind at end of stack+store CFUNWIND (xip not end of stack). |
| UInt Fw; // unwind at end of stack+store FPUNWIND |
| UInt FO; // unwind + store FPUNWIND |
| UInt CF; // unwind + store CFUNWIND. Details below. |
| UInt xi; UInt xs; UInt xb; // register(s) which caused a 'store CFUNWIND'. |
| UInt Ck; // unwind fp invalid+store FPUNWIND |
| UInt MS; // microsoft unwind |
| } stats; |
| |
| const Bool debug = False; |
| // = VG_(debugLog_getLevel) () > 3; |
| // = True; |
| // = stats.nr >= 123456; |
| const HChar* unwind_case; // used when debug is True. |
| // Debugging this function is not straightforward. |
| // Here is the easiest way I have found: |
| // 1. Change the above to True. |
| // 2. Start your program under Valgrind with --tool=none --vgdb-error=0 |
| // 3. Use GDB/vgdb to put a breakpoint where you want to debug the stacktrace |
| // 4. Continue till breakpoint is encountered |
| // 5. From GDB, use 'monitor v.info scheduler' and examine the unwind traces. |
| // You might have to do twice 'monitor v.info scheduler' to see |
| // the effect of caching the results of the verification. |
| // You can also modify the debug dynamically using by using |
| // 'monitor v.set debuglog 4. |
| |
| Int i; |
| Addr fp_max; |
| UInt n_found = 0; |
| const Int cmrf = VG_(clo_merge_recursive_frames); |
| |
| vg_assert(sizeof(Addr) == sizeof(UWord)); |
| vg_assert(sizeof(Addr) == sizeof(void*)); |
| |
| D3UnwindRegs fpverif_uregs; // result of CF unwind for a check reason. |
| Addr xip_verified = 0; // xip for which we have calculated fpverif_uregs |
| // 0 assigned to silence false positive -Wuninitialized warning |
| // This is a false positive as xip_verified is assigned when |
| // xip_verif > CFUNWIND and only used if xip_verif > CFUNWIND. |
| |
| D3UnwindRegs uregs; |
| uregs.xip = (Addr)startRegs->r_pc; |
| uregs.xsp = (Addr)startRegs->r_sp; |
| uregs.xbp = startRegs->misc.X86.r_ebp; |
| Addr fp_min = uregs.xsp; |
| |
| /* Snaffle IPs from the client's stack into ips[0 .. max_n_ips-1], |
| stopping when the trail goes cold, which we guess to be |
| when FP is not a reasonable stack location. */ |
| |
| // 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 = VG_PGROUNDUP(fp_max_orig); |
| if (fp_max >= sizeof(Addr)) |
| fp_max -= sizeof(Addr); |
| |
| if (debug) |
| VG_(printf)("max_n_ips=%d fp_min=0x%lx fp_max_orig=0x%lx, " |
| "fp_max=0x%lx ip=0x%lx fp=0x%lx\n", |
| max_n_ips, fp_min, fp_max_orig, fp_max, |
| uregs.xip, uregs.xbp); |
| |
| /* 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);*/ |
| // On Darwin, this kicks in for pthread-related stack traces, so they're |
| // only 1 entry long which is wrong. |
| # if !defined(VGO_darwin) |
| if (fp_min + 512 >= fp_max) { |
| /* If the stack limits look bogus, don't poke around ... but |
| don't bomb out either. */ |
| if (sps) sps[0] = uregs.xsp; |
| if (fps) fps[0] = uregs.xbp; |
| ips[0] = uregs.xip; |
| return 1; |
| } |
| # endif |
| |
| if (UNLIKELY (fp_CF_verif_generation != VG_(CF_info_generation)())) { |
| fp_CF_verif_generation = VG_(CF_info_generation)(); |
| VG_(memset)(&fp_CF_verif_cache, 0, sizeof(fp_CF_verif_cache)); |
| } |
| |
| |
| /* Loop unwinding the stack. Note that the IP value we get on |
| * each pass (whether from CFI info or a stack frame) is a |
| * return address so is actually after the calling instruction |
| * in the calling function. |
| * |
| * Because of this we subtract one from the IP after each pass |
| * of the loop so that we find the right CFI block on the next |
| * pass - otherwise we can find the wrong CFI info if it happens |
| * to change after the calling instruction and that will mean |
| * that we will fail to unwind the next step. |
| * |
| * This most frequently happens at the end of a function when |
| * a tail call occurs and we wind up using the CFI info for the |
| * next function which is completely wrong. |
| */ |
| if (sps) sps[0] = uregs.xsp; |
| if (fps) fps[0] = uregs.xbp; |
| ips[0] = uregs.xip; |
| i = 1; |
| if (do_stats) stats.nr++; |
| |
| while (True) { |
| |
| if (i >= max_n_ips) |
| break; |
| |
| UWord hash = uregs.xip % N_FP_CF_VERIF; |
| Addr xip_verif = uregs.xip ^ fp_CF_verif_cache [hash]; |
| if (debug) |
| VG_(printf)(" uregs.xip 0x%08lx xip_verif[0x%08lx]\n", |
| uregs.xip, xip_verif); |
| // If xip is in cache, then xip_verif will be <= CFUNWIND. |
| // Otherwise, if not in cache, xip_verif will be > CFUNWIND. |
| |
| /* Try to derive a new (ip,sp,fp) triple from the current set. */ |
| |
| /* Do we have to do CFI unwinding ? |
| We do CFI unwinding if one of the following condition holds: |
| a. fp_CF_verif_cache contains xip but indicates CFUNWIND must |
| be done (i.e. fp unwind check failed when we did the first |
| unwind for this IP). |
| b. fp_CF_verif_cache does not contain xip. |
| We will try CFI unwinding in fpverif_uregs and compare with |
| FP unwind result to insert xip in the cache with the correct |
| indicator. */ |
| if (UNLIKELY(xip_verif >= CFUNWIND)) { |
| if (xip_verif == CFUNWIND) { |
| /* case a : do "real" cfi unwind */ |
| if ( VG_(use_CF_info)( &uregs, fp_min, fp_max ) ) { |
| if (debug) unwind_case = "Ca"; |
| if (do_stats) stats.Ca++; |
| goto unwind_done; |
| } |
| /* ??? cache indicates we have to do CFI unwind (so, we |
| previously found CFI info, and failed the fp unwind |
| check). Now, we just failed with CFI. So, once we |
| succeed, once we fail. No idea what is going on => |
| cleanup the cache entry and fallover to fp unwind (this |
| time). */ |
| fp_CF_verif_cache [hash] = 0; |
| if (debug) VG_(printf)(" cache reset as CFI ok then nok\n"); |
| //??? stats |
| xip_verif = NOINFO; |
| } else { |
| /* case b : do "verif" cfi unwind in fpverif_uregs */ |
| fpverif_uregs = uregs; |
| xip_verified = uregs.xip; |
| if ( !VG_(use_CF_info)( &fpverif_uregs, fp_min, fp_max ) ) { |
| fp_CF_verif_cache [hash] = uregs.xip ^ NOINFO; |
| if (debug) VG_(printf)(" cache NOINFO fpverif_uregs\n"); |
| xip_verif = NOINFO; |
| } |
| } |
| } |
| |
| /* On x86, try the old-fashioned method of following the |
| %ebp-chain. This can be done if the fp_CF_verif_cache for xip |
| indicate fp unwind is ok. This must be done if the cache indicates |
| there is no info. This is also done to confirm what to put in the cache |
| if xip was not in the cache. */ |
| /* This deals with frames resulting from functions which begin "pushl% |
| ebp ; movl %esp, %ebp" which is the ABI-mandated preamble. */ |
| if (fp_min <= uregs.xbp && |
| uregs.xbp <= fp_max - 1 * sizeof(UWord)/*see comment below*/) |
| { |
| /* fp looks sane, so use it. */ |
| uregs.xip = (((UWord*)uregs.xbp)[1]); |
| // We stop if we hit a zero (the traditional end-of-stack |
| // marker) or a one -- these correspond to recorded IPs of 0 or -1. |
| // The latter because r8818 (in this file) changes the meaning of |
| // entries [1] and above in a stack trace, by subtracting 1 from |
| // them. Hence stacks that used to end with a zero value now end in |
| // -1 and so we must detect that too. |
| if (0 == uregs.xip || 1 == uregs.xip) { |
| if (xip_verif > CFUNWIND) { |
| // Check if we obtain the same result with fp unwind. |
| // If same result, then mark xip as fp unwindable |
| if (uregs.xip == fpverif_uregs.xip) { |
| fp_CF_verif_cache [hash] = xip_verified ^ FPUNWIND; |
| if (debug) VG_(printf)(" cache FPUNWIND 0\n"); |
| unwind_case = "Fw"; |
| if (do_stats) stats.Fw++; |
| break; |
| } else { |
| fp_CF_verif_cache [hash] = xip_verified ^ CFUNWIND; |
| uregs = fpverif_uregs; |
| if (debug) VG_(printf)(" cache CFUNWIND 0\n"); |
| unwind_case = "Cf"; |
| if (do_stats) stats.Cf++; |
| goto unwind_done; |
| } |
| } else { |
| // end of stack => out of the loop. |
| break; |
| } |
| } |
| |
| uregs.xsp = uregs.xbp + sizeof(Addr) /*saved %ebp*/ |
| + sizeof(Addr) /*ra*/; |
| uregs.xbp = (((UWord*)uregs.xbp)[0]); |
| if (xip_verif > CFUNWIND) { |
| if (uregs.xip == fpverif_uregs.xip |
| && uregs.xsp == fpverif_uregs.xsp |
| && uregs.xbp == fpverif_uregs.xbp) { |
| fp_CF_verif_cache [hash] = xip_verified ^ FPUNWIND; |
| if (debug) VG_(printf)(" cache FPUNWIND >2\n"); |
| if (debug) unwind_case = "FO"; |
| if (do_stats) stats.FO++; |
| } else { |
| fp_CF_verif_cache [hash] = xip_verified ^ CFUNWIND; |
| if (debug) VG_(printf)(" cache CFUNWIND >2\n"); |
| if (do_stats && uregs.xip != fpverif_uregs.xip) stats.xi++; |
| if (do_stats && uregs.xsp != fpverif_uregs.xsp) stats.xs++; |
| if (do_stats && uregs.xbp != fpverif_uregs.xbp) stats.xb++; |
| uregs = fpverif_uregs; |
| if (debug) unwind_case = "CF"; |
| if (do_stats) stats.CF++; |
| } |
| } else { |
| if (debug) unwind_case = "FF"; |
| if (do_stats) stats.FF++; |
| } |
| goto unwind_done; |
| } else { |
| // fp unwind has failed. |
| // If we were checking the validity of the cfi unwinding, |
| // we mark in the cache that the fp unwind cannot be done, and that |
| // cfi unwind is desired. |
| if (xip_verif > CFUNWIND) { |
| // We know that fpverif_uregs contains valid information, |
| // as a failed cf unwind would have put NOINFO in xip_verif. |
| fp_CF_verif_cache [hash] = xip_verified ^ CFUNWIND; |
| if (debug) VG_(printf)(" cache CFUNWIND as fp failed\n"); |
| uregs = fpverif_uregs; |
| if (debug) unwind_case = "Ck"; |
| if (do_stats) stats.Ck++; |
| goto unwind_done; |
| } |
| // xip_verif is FPUNWIND or NOINFO. |
| // We failed the cfi unwind and/or the fp unwind. |
| // => fallback to FPO info. |
| } |
| |
| /* And, similarly, try for MSVC FPO unwind info. */ |
| if ( VG_(use_FPO_info)( &uregs.xip, &uregs.xsp, &uregs.xbp, |
| fp_min, fp_max ) ) { |
| if (debug) unwind_case = "MS"; |
| if (do_stats) stats.MS++; |
| goto unwind_done; |
| } |
| |
| /* No luck. We have to give up. */ |
| break; |
| |
| unwind_done: |
| /* Add a frame in ips/sps/fps */ |
| /* fp is %ebp. sp is %esp. ip is %eip. */ |
| if (0 == uregs.xip || 1 == uregs.xip) break; |
| if (sps) sps[i] = uregs.xsp; |
| if (fps) fps[i] = uregs.xbp; |
| ips[i++] = uregs.xip - 1; |
| /* -1: refer to calling insn, not the RA */ |
| if (debug) |
| VG_(printf)(" ips%s[%d]=0x%08lx\n", unwind_case, i-1, ips[i-1]); |
| uregs.xip = uregs.xip - 1; |
| /* as per comment at the head of this loop */ |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| } |
| |
| if (do_stats) stats.nf += i; |
| if (do_stats && stats.nr % 10000 == 0) { |
| VG_(printf)("nr %u nf %u " |
| "Ca %u FF %u " |
| "Cf %u " |
| "Fw %u FO %u " |
| "CF %u (xi %u xs %u xb %u) " |
| "Ck %u MS %u\n", |
| stats.nr, stats.nf, |
| stats.Ca, stats.FF, |
| stats.Cf, |
| stats.Fw, stats.FO, |
| stats.CF, stats.xi, stats.xs, stats.xb, |
| stats.Ck, stats.MS); |
| } |
| n_found = i; |
| return n_found; |
| } |
| |
| #undef N_FP_CF_VERIF |
| #undef FPUNWIND |
| #undef NOINFO |
| #undef CFUNWIND |
| |
| #endif |
| |
| /* ----------------------- amd64 ------------------------ */ |
| |
| #if defined(VGP_amd64_linux) || defined(VGP_amd64_darwin) |
| |
| UInt VG_(get_StackTrace_wrk) ( ThreadId tid_if_known, |
| /*OUT*/Addr* ips, UInt max_n_ips, |
| /*OUT*/Addr* sps, /*OUT*/Addr* fps, |
| UnwindStartRegs* startRegs, |
| Addr fp_max_orig ) |
| { |
| Bool debug = False; |
| Int i; |
| Addr fp_max; |
| UInt n_found = 0; |
| const Int cmrf = VG_(clo_merge_recursive_frames); |
| |
| vg_assert(sizeof(Addr) == sizeof(UWord)); |
| vg_assert(sizeof(Addr) == sizeof(void*)); |
| |
| D3UnwindRegs uregs; |
| uregs.xip = startRegs->r_pc; |
| uregs.xsp = startRegs->r_sp; |
| uregs.xbp = startRegs->misc.AMD64.r_rbp; |
| Addr fp_min = uregs.xsp; |
| |
| /* Snaffle IPs from the client's stack into ips[0 .. max_n_ips-1], |
| stopping when the trail goes cold, which we guess to be |
| when FP is not a reasonable stack location. */ |
| |
| // 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 = VG_PGROUNDUP(fp_max_orig); |
| if (fp_max >= sizeof(Addr)) |
| fp_max -= sizeof(Addr); |
| |
| if (debug) |
| VG_(printf)("max_n_ips=%d fp_min=0x%lx fp_max_orig=0x%lx, " |
| "fp_max=0x%lx ip=0x%lx fp=0x%lx\n", |
| max_n_ips, fp_min, fp_max_orig, fp_max, |
| uregs.xip, uregs.xbp); |
| |
| /* 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);*/ |
| // On Darwin, this kicks in for pthread-related stack traces, so they're |
| // only 1 entry long which is wrong. |
| # if !defined(VGO_darwin) |
| if (fp_min + 256 >= fp_max) { |
| /* If the stack limits look bogus, don't poke around ... but |
| don't bomb out either. */ |
| if (sps) sps[0] = uregs.xsp; |
| if (fps) fps[0] = uregs.xbp; |
| ips[0] = uregs.xip; |
| return 1; |
| } |
| # endif |
| |
| /* fp is %rbp. sp is %rsp. ip is %rip. */ |
| |
| ips[0] = uregs.xip; |
| if (sps) sps[0] = uregs.xsp; |
| if (fps) fps[0] = uregs.xbp; |
| i = 1; |
| |
| /* Loop unwinding the stack. Note that the IP value we get on |
| * each pass (whether from CFI info or a stack frame) is a |
| * return address so is actually after the calling instruction |
| * in the calling function. |
| * |
| * Because of this we subtract one from the IP after each pass |
| * of the loop so that we find the right CFI block on the next |
| * pass - otherwise we can find the wrong CFI info if it happens |
| * to change after the calling instruction and that will mean |
| * that we will fail to unwind the next step. |
| * |
| * This most frequently happens at the end of a function when |
| * a tail call occurs and we wind up using the CFI info for the |
| * next function which is completely wrong. |
| */ |
| while (True) { |
| |
| if (i >= max_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_CF_info)( &uregs, fp_min, fp_max ) ) { |
| if (0 == uregs.xip || 1 == uregs.xip) break; |
| if (sps) sps[i] = uregs.xsp; |
| if (fps) fps[i] = uregs.xbp; |
| ips[i++] = uregs.xip - 1; /* -1: refer to calling insn, not the RA */ |
| if (debug) |
| VG_(printf)(" ipsC[%d]=%#08lx\n", i-1, ips[i-1]); |
| uregs.xip = uregs.xip - 1; /* as per comment at the head of this loop */ |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| continue; |
| } |
| |
| /* If VG_(use_CF_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 "pushq %rbp ; movq %rsp, %rbp". |
| 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. */ |
| /* Note: re "- 1 * sizeof(UWord)", need to take account of the |
| fact that we are prodding at & ((UWord*)fp)[1] and so need to |
| adjust the limit check accordingly. Omitting this has been |
| observed to cause segfaults on rare occasions. */ |
| if (fp_min <= uregs.xbp && uregs.xbp <= fp_max - 1 * sizeof(UWord)) { |
| /* fp looks sane, so use it. */ |
| uregs.xip = (((UWord*)uregs.xbp)[1]); |
| if (0 == uregs.xip || 1 == uregs.xip) break; |
| uregs.xsp = uregs.xbp + sizeof(Addr) /*saved %rbp*/ |
| + sizeof(Addr) /*ra*/; |
| uregs.xbp = (((UWord*)uregs.xbp)[0]); |
| if (sps) sps[i] = uregs.xsp; |
| if (fps) fps[i] = uregs.xbp; |
| ips[i++] = uregs.xip - 1; /* -1: refer to calling insn, not the RA */ |
| if (debug) |
| VG_(printf)(" ipsF[%d]=%#08lx\n", i-1, ips[i-1]); |
| uregs.xip = uregs.xip - 1; /* as per comment at the head of this loop */ |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| continue; |
| } |
| |
| /* Last-ditch hack (evidently GDB does something similar). We |
| are in the middle of nowhere and we have a nonsense value for |
| the frame pointer. If the stack pointer is still valid, |
| assume that what it points at is a return address. Yes, |
| desperate measures. Could do better here: |
| - check that the supposed return address is in |
| an executable page |
| - check that the supposed return address is just after a call insn |
| - given those two checks, don't just consider *sp as the return |
| address; instead scan a likely section of stack (eg sp .. sp+256) |
| and use suitable values found there. |
| */ |
| if (fp_min <= uregs.xsp && uregs.xsp < fp_max) { |
| uregs.xip = ((UWord*)uregs.xsp)[0]; |
| if (0 == uregs.xip || 1 == uregs.xip) break; |
| if (sps) sps[i] = uregs.xsp; |
| if (fps) fps[i] = uregs.xbp; |
| ips[i++] = uregs.xip == 0 |
| ? 0 /* sp[0] == 0 ==> stuck at the bottom of a |
| thread stack */ |
| : uregs.xip - 1; |
| /* -1: refer to calling insn, not the RA */ |
| if (debug) |
| VG_(printf)(" ipsH[%d]=%#08lx\n", i-1, ips[i-1]); |
| uregs.xip = uregs.xip - 1; /* as per comment at the head of this loop */ |
| uregs.xsp += 8; |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| continue; |
| } |
| |
| /* No luck at all. We have to give up. */ |
| break; |
| } |
| |
| n_found = i; |
| return n_found; |
| } |
| |
| #endif |
| |
| /* -----------------------ppc32/64 ---------------------- */ |
| |
| #if defined(VGP_ppc32_linux) || defined(VGP_ppc64_linux) |
| |
| UInt VG_(get_StackTrace_wrk) ( ThreadId tid_if_known, |
| /*OUT*/Addr* ips, UInt max_n_ips, |
| /*OUT*/Addr* sps, /*OUT*/Addr* fps, |
| UnwindStartRegs* startRegs, |
| Addr fp_max_orig ) |
| { |
| Bool lr_is_first_RA = False; |
| # if defined(VG_PLAT_USES_PPCTOC) |
| Word redir_stack_size = 0; |
| Word redirs_used = 0; |
| # endif |
| const Int cmrf = VG_(clo_merge_recursive_frames); |
| |
| Bool debug = False; |
| Int i; |
| Addr fp_max; |
| UInt n_found = 0; |
| |
| vg_assert(sizeof(Addr) == sizeof(UWord)); |
| vg_assert(sizeof(Addr) == sizeof(void*)); |
| |
| Addr ip = (Addr)startRegs->r_pc; |
| Addr sp = (Addr)startRegs->r_sp; |
| Addr fp = sp; |
| # if defined(VGP_ppc32_linux) |
| Addr lr = startRegs->misc.PPC32.r_lr; |
| # elif defined(VGP_ppc64_linux) |
| Addr lr = startRegs->misc.PPC64.r_lr; |
| # endif |
| Addr fp_min = sp; |
| |
| /* Snaffle IPs from the client's stack into ips[0 .. max_n_ips-1], |
| stopping when the trail goes cold, which we guess to be |
| when FP is not a reasonable stack location. */ |
| |
| // 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 = VG_PGROUNDUP(fp_max_orig); |
| if (fp_max >= sizeof(Addr)) |
| fp_max -= sizeof(Addr); |
| |
| if (debug) |
| VG_(printf)("max_n_ips=%d fp_min=0x%lx fp_max_orig=0x%lx, " |
| "fp_max=0x%lx ip=0x%lx fp=0x%lx\n", |
| max_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);*/ |
| if (fp_min + 512 >= fp_max) { |
| /* If the stack limits look bogus, don't poke around ... but |
| don't bomb out either. */ |
| if (sps) sps[0] = sp; |
| if (fps) fps[0] = fp; |
| ips[0] = ip; |
| return 1; |
| } |
| |
| /* fp is %r1. ip is %cia. Note, ppc uses r1 as both the stack and |
| frame pointers. */ |
| |
| # if defined(VGP_ppc64_linux) |
| redir_stack_size = VEX_GUEST_PPC64_REDIR_STACK_SIZE; |
| redirs_used = 0; |
| # endif |
| |
| # if defined(VG_PLAT_USES_PPCTOC) |
| /* Deal with bogus LR values caused by function |
| interception/wrapping on ppc-TOC platforms; see comment on |
| similar code a few lines further down. */ |
| if (ULong_to_Ptr(lr) == (void*)&VG_(ppctoc_magic_redirect_return_stub) |
| && VG_(is_valid_tid)(tid_if_known)) { |
| Word hsp = VG_(threads)[tid_if_known].arch.vex.guest_REDIR_SP; |
| redirs_used++; |
| if (hsp >= 1 && hsp < redir_stack_size) |
| lr = VG_(threads)[tid_if_known] |
| .arch.vex.guest_REDIR_STACK[hsp-1]; |
| } |
| # endif |
| |
| /* We have to determine whether or not LR currently holds this fn |
| (call it F)'s return address. It might not if F has previously |
| called some other function, hence overwriting LR with a pointer |
| to some part of F. Hence if LR and IP point to the same |
| function then we conclude LR does not hold this function's |
| return address; instead the LR at entry must have been saved in |
| the stack by F's prologue and so we must get it from there |
| instead. Note all this guff only applies to the innermost |
| frame. */ |
| lr_is_first_RA = False; |
| { |
| # define M_VG_ERRTXT 1000 |
| HChar buf_lr[M_VG_ERRTXT], buf_ip[M_VG_ERRTXT]; |
| /* The following conditional looks grossly inefficient and |
| surely could be majorly improved, with not much effort. */ |
| if (VG_(get_fnname_raw) (lr, buf_lr, M_VG_ERRTXT)) |
| if (VG_(get_fnname_raw) (ip, buf_ip, M_VG_ERRTXT)) |
| if (VG_(strncmp)(buf_lr, buf_ip, M_VG_ERRTXT)) |
| lr_is_first_RA = True; |
| # undef M_VG_ERRTXT |
| } |
| |
| if (sps) sps[0] = fp; /* NB. not sp */ |
| if (fps) fps[0] = fp; |
| ips[0] = ip; |
| i = 1; |
| |
| if (fp_min <= fp && fp < fp_max-VG_WORDSIZE+1) { |
| |
| /* initial FP is sane; keep going */ |
| fp = (((UWord*)fp)[0]); |
| |
| while (True) { |
| |
| /* On ppc64-linux (ppc64-elf, really), the lr save |
| slot is 2 words back from sp, whereas on ppc32-elf(?) it's |
| only one word back. */ |
| # if defined(VG_PLAT_USES_PPCTOC) |
| const Int lr_offset = 2; |
| # else |
| const Int lr_offset = 1; |
| # endif |
| |
| if (i >= max_n_ips) |
| break; |
| |
| /* Try to derive a new (ip,fp) pair from the current set. */ |
| |
| if (fp_min <= fp && fp <= fp_max - lr_offset * sizeof(UWord)) { |
| /* fp looks sane, so use it. */ |
| |
| if (i == 1 && lr_is_first_RA) |
| ip = lr; |
| else |
| ip = (((UWord*)fp)[lr_offset]); |
| |
| # if defined(VG_PLAT_USES_PPCTOC) |
| /* Nasty hack to do with function replacement/wrapping on |
| ppc64-linux. If LR points to our magic return stub, |
| then we are in a wrapped or intercepted function, in |
| which LR has been messed with. The original LR will |
| have been pushed onto the thread's hidden REDIR stack |
| one down from the top (top element is the saved R2) and |
| so we should restore the value from there instead. |
| Since nested redirections can and do happen, we keep |
| track of the number of nested LRs used by the unwinding |
| so far with 'redirs_used'. */ |
| if (ip == (Addr)&VG_(ppctoc_magic_redirect_return_stub) |
| && VG_(is_valid_tid)(tid_if_known)) { |
| Word hsp = VG_(threads)[tid_if_known] |
| .arch.vex.guest_REDIR_SP; |
| hsp -= 2 * redirs_used; |
| redirs_used ++; |
| if (hsp >= 1 && hsp < redir_stack_size) |
| ip = VG_(threads)[tid_if_known] |
| .arch.vex.guest_REDIR_STACK[hsp-1]; |
| } |
| # endif |
| |
| if (0 == ip || 1 == ip) break; |
| if (sps) sps[i] = fp; /* NB. not sp */ |
| if (fps) fps[i] = fp; |
| fp = (((UWord*)fp)[0]); |
| ips[i++] = ip - 1; /* -1: refer to calling insn, not the RA */ |
| if (debug) |
| VG_(printf)(" ipsF[%d]=%#08lx\n", i-1, ips[i-1]); |
| ip = ip - 1; /* ip is probably dead at this point, but |
| play safe, a la x86/amd64 above. See |
| extensive comments above. */ |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| continue; |
| } |
| |
| /* No luck there. We have to give up. */ |
| break; |
| } |
| } |
| |
| n_found = i; |
| return n_found; |
| } |
| |
| #endif |
| |
| /* ------------------------ arm ------------------------- */ |
| |
| #if defined(VGP_arm_linux) |
| |
| static Bool in_same_fn ( Addr a1, Addr a2 ) |
| { |
| # define M_VG_ERRTXT 500 |
| HChar buf_a1[M_VG_ERRTXT], buf_a2[M_VG_ERRTXT]; |
| /* The following conditional looks grossly inefficient and |
| surely could be majorly improved, with not much effort. */ |
| if (VG_(get_fnname_raw) (a1, buf_a1, M_VG_ERRTXT)) |
| if (VG_(get_fnname_raw) (a2, buf_a2, M_VG_ERRTXT)) |
| if (VG_(strncmp)(buf_a1, buf_a2, M_VG_ERRTXT)) |
| return True; |
| # undef M_VG_ERRTXT |
| return False; |
| } |
| |
| static Bool in_same_page ( Addr a1, Addr a2 ) { |
| return (a1 & ~0xFFF) == (a2 & ~0xFFF); |
| } |
| |
| static Addr abs_diff ( Addr a1, Addr a2 ) { |
| return (Addr)(a1 > a2 ? a1 - a2 : a2 - a1); |
| } |
| |
| static Bool has_XT_perms ( Addr a ) |
| { |
| NSegment const* seg = VG_(am_find_nsegment)(a); |
| return seg && seg->hasX && seg->hasT; |
| } |
| |
| static Bool looks_like_Thumb_call32 ( UShort w0, UShort w1 ) |
| { |
| if (0) |
| VG_(printf)("isT32call %04x %04x\n", (UInt)w0, (UInt)w1); |
| // BL simm26 |
| if ((w0 & 0xF800) == 0xF000 && (w1 & 0xC000) == 0xC000) return True; |
| // BLX simm26 |
| if ((w0 & 0xF800) == 0xF000 && (w1 & 0xC000) == 0xC000) return True; |
| return False; |
| } |
| |
| static Bool looks_like_Thumb_call16 ( UShort w0 ) |
| { |
| return False; |
| } |
| |
| static Bool looks_like_ARM_call ( UInt a0 ) |
| { |
| if (0) |
| VG_(printf)("isA32call %08x\n", a0); |
| // Leading E forces unconditional only -- fix |
| if ((a0 & 0xFF000000) == 0xEB000000) return True; |
| return False; |
| } |
| |
| static Bool looks_like_RA ( Addr ra ) |
| { |
| /* 'ra' is a plausible return address if it points to |
| an instruction after a call insn. */ |
| Bool isT = (ra & 1); |
| if (isT) { |
| // returning to Thumb code |
| ra &= ~1; |
| ra -= 4; |
| if (has_XT_perms(ra)) { |
| UShort w0 = *(UShort*)ra; |
| UShort w1 = in_same_page(ra, ra+2) ? *(UShort*)(ra+2) : 0; |
| if (looks_like_Thumb_call16(w1) || looks_like_Thumb_call32(w0,w1)) |
| return True; |
| } |
| } else { |
| // ARM |
| ra &= ~3; |
| ra -= 4; |
| if (has_XT_perms(ra)) { |
| UInt a0 = *(UInt*)ra; |
| if (looks_like_ARM_call(a0)) |
| return True; |
| } |
| } |
| return False; |
| } |
| |
| UInt VG_(get_StackTrace_wrk) ( ThreadId tid_if_known, |
| /*OUT*/Addr* ips, UInt max_n_ips, |
| /*OUT*/Addr* sps, /*OUT*/Addr* fps, |
| UnwindStartRegs* startRegs, |
| Addr fp_max_orig ) |
| { |
| Bool debug = False; |
| Int i; |
| Addr fp_max; |
| UInt n_found = 0; |
| const Int cmrf = VG_(clo_merge_recursive_frames); |
| |
| vg_assert(sizeof(Addr) == sizeof(UWord)); |
| vg_assert(sizeof(Addr) == sizeof(void*)); |
| |
| D3UnwindRegs uregs; |
| uregs.r15 = startRegs->r_pc & 0xFFFFFFFE; |
| uregs.r14 = startRegs->misc.ARM.r14; |
| uregs.r13 = startRegs->r_sp; |
| uregs.r12 = startRegs->misc.ARM.r12; |
| uregs.r11 = startRegs->misc.ARM.r11; |
| uregs.r7 = startRegs->misc.ARM.r7; |
| Addr fp_min = uregs.r13; |
| |
| /* Snaffle IPs from the client's stack into ips[0 .. max_n_ips-1], |
| stopping when the trail goes cold, which we guess to be |
| when FP is not a reasonable stack location. */ |
| |
| // 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 = VG_PGROUNDUP(fp_max_orig); |
| if (fp_max >= sizeof(Addr)) |
| fp_max -= sizeof(Addr); |
| |
| if (debug) |
| VG_(printf)("\nmax_n_ips=%d fp_min=0x%lx fp_max_orig=0x%lx, " |
| "fp_max=0x%lx r15=0x%lx r13=0x%lx\n", |
| max_n_ips, fp_min, fp_max_orig, fp_max, |
| uregs.r15, uregs.r13); |
| |
| /* 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);*/ |
| // On Darwin, this kicks in for pthread-related stack traces, so they're |
| // only 1 entry long which is wrong. |
| if (fp_min + 512 >= fp_max) { |
| /* If the stack limits look bogus, don't poke around ... but |
| don't bomb out either. */ |
| if (sps) sps[0] = uregs.r13; |
| if (fps) fps[0] = 0; |
| ips[0] = uregs.r15; |
| return 1; |
| } |
| |
| /* */ |
| |
| if (sps) sps[0] = uregs.r13; |
| if (fps) fps[0] = 0; |
| ips[0] = uregs.r15; |
| i = 1; |
| |
| /* Loop unwinding the stack. */ |
| Bool do_stack_scan = False; |
| |
| /* First try the Official Way, using Dwarf CFI. */ |
| while (True) { |
| if (debug) { |
| VG_(printf)("i: %d, r15: 0x%lx, r13: 0x%lx\n", |
| i, uregs.r15, uregs.r13); |
| } |
| |
| if (i >= max_n_ips) |
| break; |
| |
| if (VG_(use_CF_info)( &uregs, fp_min, fp_max )) { |
| if (sps) sps[i] = uregs.r13; |
| if (fps) fps[i] = 0; |
| ips[i++] = (uregs.r15 & 0xFFFFFFFE) - 1; |
| if (debug) |
| VG_(printf)("USING CFI: r15: 0x%lx, r13: 0x%lx\n", |
| uregs.r15, uregs.r13); |
| uregs.r15 = (uregs.r15 & 0xFFFFFFFE) - 1; |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| continue; |
| } |
| |
| /* No luck. We have to give up. */ |
| do_stack_scan = True; |
| break; |
| } |
| |
| /* Now try Plan B (maybe) -- stack scanning. This often gives |
| pretty bad results, so this has to be enabled explicitly by the |
| user. */ |
| if (do_stack_scan |
| && i < max_n_ips && i < (Int)VG_(clo_unw_stack_scan_thresh)) { |
| Int nByStackScan = 0; |
| Addr lr = uregs.r14; |
| Addr sp = uregs.r13 & ~3; |
| Addr pc = uregs.r15; |
| // First see if LR contains |
| // something that could be a valid return address. |
| if (!in_same_fn(lr, pc) && looks_like_RA(lr)) { |
| // take it only if 'cand' isn't obviously a duplicate |
| // of the last found IP value |
| Addr cand = (lr & 0xFFFFFFFE) - 1; |
| if (abs_diff(cand, ips[i-1]) > 1) { |
| if (sps) sps[i] = 0; |
| if (fps) fps[i] = 0; |
| ips[i++] = cand; |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| nByStackScan++; |
| } |
| } |
| while (in_same_page(sp, uregs.r13)) { |
| if (i >= max_n_ips) |
| break; |
| // we're in the same page; fairly safe to keep going |
| UWord w = *(UWord*)(sp & ~0x3); |
| if (looks_like_RA(w)) { |
| Addr cand = (w & 0xFFFFFFFE) - 1; |
| // take it only if 'cand' isn't obviously a duplicate |
| // of the last found IP value |
| if (abs_diff(cand, ips[i-1]) > 1) { |
| if (sps) sps[i] = 0; |
| if (fps) fps[i] = 0; |
| ips[i++] = cand; |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| if (++nByStackScan >= VG_(clo_unw_stack_scan_frames)) break; |
| } |
| } |
| sp += 4; |
| } |
| } |
| |
| n_found = i; |
| return n_found; |
| } |
| |
| #endif |
| |
| /* ------------------------ arm64 ------------------------- */ |
| |
| #if defined(VGP_arm64_linux) |
| |
| UInt VG_(get_StackTrace_wrk) ( ThreadId tid_if_known, |
| /*OUT*/Addr* ips, UInt max_n_ips, |
| /*OUT*/Addr* sps, /*OUT*/Addr* fps, |
| UnwindStartRegs* startRegs, |
| Addr fp_max_orig ) |
| { |
| Bool debug = False; |
| Int i; |
| Addr fp_max; |
| UInt n_found = 0; |
| const Int cmrf = VG_(clo_merge_recursive_frames); |
| |
| vg_assert(sizeof(Addr) == sizeof(UWord)); |
| vg_assert(sizeof(Addr) == sizeof(void*)); |
| |
| D3UnwindRegs uregs; |
| uregs.pc = startRegs->r_pc; |
| uregs.sp = startRegs->r_sp; |
| uregs.x30 = startRegs->misc.ARM64.x30; |
| uregs.x29 = startRegs->misc.ARM64.x29; |
| Addr fp_min = uregs.sp; |
| |
| /* Snaffle IPs from the client's stack into ips[0 .. max_n_ips-1], |
| stopping when the trail goes cold, which we guess to be |
| when FP is not a reasonable stack location. */ |
| |
| // 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 = VG_PGROUNDUP(fp_max_orig); |
| if (fp_max >= sizeof(Addr)) |
| fp_max -= sizeof(Addr); |
| |
| if (debug) |
| VG_(printf)("\nmax_n_ips=%d fp_min=0x%lx fp_max_orig=0x%lx, " |
| "fp_max=0x%lx PC=0x%lx SP=0x%lx\n", |
| max_n_ips, fp_min, fp_max_orig, fp_max, |
| uregs.pc, uregs.sp); |
| |
| /* 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);*/ |
| // On Darwin, this kicks in for pthread-related stack traces, so they're |
| // only 1 entry long which is wrong. |
| if (fp_min + 512 >= fp_max) { |
| /* If the stack limits look bogus, don't poke around ... but |
| don't bomb out either. */ |
| if (sps) sps[0] = uregs.sp; |
| if (fps) fps[0] = uregs.x29; |
| ips[0] = uregs.pc; |
| return 1; |
| } |
| |
| /* */ |
| |
| if (sps) sps[0] = uregs.sp; |
| if (fps) fps[0] = uregs.x29; |
| ips[0] = uregs.pc; |
| i = 1; |
| |
| /* Loop unwinding the stack, using CFI. */ |
| while (True) { |
| if (debug) { |
| VG_(printf)("i: %d, pc: 0x%lx, sp: 0x%lx\n", |
| i, uregs.pc, uregs.sp); |
| } |
| |
| if (i >= max_n_ips) |
| break; |
| |
| if (VG_(use_CF_info)( &uregs, fp_min, fp_max )) { |
| if (sps) sps[i] = uregs.sp; |
| if (fps) fps[i] = uregs.x29; |
| ips[i++] = uregs.pc - 1; |
| if (debug) |
| VG_(printf)("USING CFI: pc: 0x%lx, sp: 0x%lx\n", |
| uregs.pc, uregs.sp); |
| uregs.pc = uregs.pc - 1; |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| continue; |
| } |
| |
| /* No luck. We have to give up. */ |
| break; |
| } |
| |
| n_found = i; |
| return n_found; |
| } |
| |
| #endif |
| |
| /* ------------------------ s390x ------------------------- */ |
| |
| #if defined(VGP_s390x_linux) |
| |
| UInt VG_(get_StackTrace_wrk) ( ThreadId tid_if_known, |
| /*OUT*/Addr* ips, UInt max_n_ips, |
| /*OUT*/Addr* sps, /*OUT*/Addr* fps, |
| UnwindStartRegs* startRegs, |
| Addr fp_max_orig ) |
| { |
| Bool debug = False; |
| Int i; |
| Addr fp_max; |
| UInt n_found = 0; |
| const Int cmrf = VG_(clo_merge_recursive_frames); |
| |
| vg_assert(sizeof(Addr) == sizeof(UWord)); |
| vg_assert(sizeof(Addr) == sizeof(void*)); |
| |
| D3UnwindRegs uregs; |
| uregs.ia = startRegs->r_pc; |
| uregs.sp = startRegs->r_sp; |
| Addr fp_min = uregs.sp; |
| uregs.fp = startRegs->misc.S390X.r_fp; |
| uregs.lr = startRegs->misc.S390X.r_lr; |
| |
| fp_max = VG_PGROUNDUP(fp_max_orig); |
| if (fp_max >= sizeof(Addr)) |
| fp_max -= sizeof(Addr); |
| |
| if (debug) |
| VG_(printf)("max_n_ips=%d fp_min=0x%lx fp_max_orig=0x%lx, " |
| "fp_max=0x%lx IA=0x%lx SP=0x%lx FP=0x%lx\n", |
| max_n_ips, fp_min, fp_max_orig, fp_max, |
| uregs.ia, uregs.sp,uregs.fp); |
| |
| /* The first frame is pretty obvious */ |
| ips[0] = uregs.ia; |
| if (sps) sps[0] = uregs.sp; |
| if (fps) fps[0] = uregs.fp; |
| i = 1; |
| |
| /* for everything else we have to rely on the eh_frame. gcc defaults to |
| not create a backchain and all the other tools (like gdb) also have |
| to use the CFI. */ |
| while (True) { |
| if (i >= max_n_ips) |
| break; |
| |
| if (VG_(use_CF_info)( &uregs, fp_min, fp_max )) { |
| if (sps) sps[i] = uregs.sp; |
| if (fps) fps[i] = uregs.fp; |
| ips[i++] = uregs.ia - 1; |
| uregs.ia = uregs.ia - 1; |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| continue; |
| } |
| /* A problem on the first frame? Lets assume it was a bad jump. |
| We will use the link register and the current stack and frame |
| pointers and see if we can use the CFI in the next round. */ |
| if (i == 1) { |
| if (sps) { |
| sps[i] = sps[0]; |
| uregs.sp = sps[0]; |
| } |
| if (fps) { |
| fps[i] = fps[0]; |
| uregs.fp = fps[0]; |
| } |
| uregs.ia = uregs.lr - 1; |
| ips[i++] = uregs.lr - 1; |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| continue; |
| } |
| |
| /* No luck. We have to give up. */ |
| break; |
| } |
| |
| n_found = i; |
| return n_found; |
| } |
| |
| #endif |
| |
| /* ------------------------ mips 32/64 ------------------------- */ |
| #if defined(VGP_mips32_linux) || defined(VGP_mips64_linux) |
| UInt VG_(get_StackTrace_wrk) ( ThreadId tid_if_known, |
| /*OUT*/Addr* ips, UInt max_n_ips, |
| /*OUT*/Addr* sps, /*OUT*/Addr* fps, |
| UnwindStartRegs* startRegs, |
| Addr fp_max_orig ) |
| { |
| Bool debug = False; |
| Int i; |
| Addr fp_max; |
| UInt n_found = 0; |
| const Int cmrf = VG_(clo_merge_recursive_frames); |
| |
| vg_assert(sizeof(Addr) == sizeof(UWord)); |
| vg_assert(sizeof(Addr) == sizeof(void*)); |
| |
| D3UnwindRegs uregs; |
| uregs.pc = startRegs->r_pc; |
| uregs.sp = startRegs->r_sp; |
| Addr fp_min = uregs.sp; |
| |
| #if defined(VGP_mips32_linux) |
| uregs.fp = startRegs->misc.MIPS32.r30; |
| uregs.ra = startRegs->misc.MIPS32.r31; |
| #elif defined(VGP_mips64_linux) |
| uregs.fp = startRegs->misc.MIPS64.r30; |
| uregs.ra = startRegs->misc.MIPS64.r31; |
| #endif |
| |
| /* Snaffle IPs from the client's stack into ips[0 .. max_n_ips-1], |
| stopping when the trail goes cold, which we guess to be |
| when FP is not a reasonable stack location. */ |
| |
| fp_max = VG_PGROUNDUP(fp_max_orig); |
| if (fp_max >= sizeof(Addr)) |
| fp_max -= sizeof(Addr); |
| |
| if (debug) |
| VG_(printf)("max_n_ips=%d fp_min=0x%lx fp_max_orig=0x%lx, " |
| "fp_max=0x%lx pc=0x%lx sp=0x%lx fp=0x%lx\n", |
| max_n_ips, fp_min, fp_max_orig, fp_max, |
| uregs.pc, uregs.sp, uregs.fp); |
| |
| if (sps) sps[0] = uregs.sp; |
| if (fps) fps[0] = uregs.fp; |
| ips[0] = uregs.pc; |
| i = 1; |
| |
| /* Loop unwinding the stack. */ |
| |
| while (True) { |
| if (debug) { |
| VG_(printf)("i: %d, pc: 0x%lx, sp: 0x%lx, ra: 0x%lx\n", |
| i, uregs.pc, uregs.sp, uregs.ra); |
| } |
| if (i >= max_n_ips) |
| break; |
| |
| D3UnwindRegs uregs_copy = uregs; |
| if (VG_(use_CF_info)( &uregs, fp_min, fp_max )) { |
| if (debug) |
| VG_(printf)("USING CFI: pc: 0x%lx, sp: 0x%lx, ra: 0x%lx\n", |
| uregs.pc, uregs.sp, uregs.ra); |
| if (0 != uregs.pc && 1 != uregs.pc) { |
| if (sps) sps[i] = uregs.sp; |
| if (fps) fps[i] = uregs.fp; |
| ips[i++] = uregs.pc - 4; |
| uregs.pc = uregs.pc - 4; |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| continue; |
| } else |
| uregs = uregs_copy; |
| } |
| |
| int seen_sp_adjust = 0; |
| long frame_offset = 0; |
| PtrdiffT offset; |
| if (VG_(get_inst_offset_in_function)(uregs.pc, &offset)) { |
| Addr start_pc = uregs.pc - offset; |
| Addr limit_pc = uregs.pc; |
| Addr cur_pc; |
| for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += 4) { |
| unsigned long inst, high_word, low_word; |
| unsigned long * cur_inst; |
| /* Fetch the instruction. */ |
| cur_inst = (unsigned long *)cur_pc; |
| inst = *((UInt *) cur_inst); |
| if(debug) |
| VG_(printf)("cur_pc: 0x%lx, inst: 0x%lx\n", cur_pc, inst); |
| |
| /* Save some code by pre-extracting some useful fields. */ |
| high_word = (inst >> 16) & 0xffff; |
| low_word = inst & 0xffff; |
| |
| if (high_word == 0x27bd /* addiu $sp,$sp,-i */ |
| || high_word == 0x23bd /* addi $sp,$sp,-i */ |
| || high_word == 0x67bd) { /* daddiu $sp,$sp,-i */ |
| if (low_word & 0x8000) /* negative stack adjustment? */ |
| frame_offset += 0x10000 - low_word; |
| else |
| /* Exit loop if a positive stack adjustment is found, which |
| usually means that the stack cleanup code in the function |
| epilogue is reached. */ |
| break; |
| seen_sp_adjust = 1; |
| } |
| } |
| if(debug) |
| VG_(printf)("offset: 0x%lx\n", frame_offset); |
| } |
| if (seen_sp_adjust) { |
| if (0 == uregs.pc || 1 == uregs.pc) break; |
| if (uregs.pc == uregs.ra - 8) break; |
| if (sps) { |
| sps[i] = uregs.sp + frame_offset; |
| } |
| uregs.sp = uregs.sp + frame_offset; |
| |
| if (fps) { |
| fps[i] = fps[0]; |
| uregs.fp = fps[0]; |
| } |
| if (0 == uregs.ra || 1 == uregs.ra) break; |
| uregs.pc = uregs.ra - 8; |
| ips[i++] = uregs.ra - 8; |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| continue; |
| } |
| |
| if (i == 1) { |
| if (sps) { |
| sps[i] = sps[0]; |
| uregs.sp = sps[0]; |
| } |
| if (fps) { |
| fps[i] = fps[0]; |
| uregs.fp = fps[0]; |
| } |
| if (0 == uregs.ra || 1 == uregs.ra) break; |
| uregs.pc = uregs.ra - 8; |
| ips[i++] = uregs.ra - 8; |
| if (UNLIKELY(cmrf > 0)) {RECURSIVE_MERGE(cmrf,ips,i);}; |
| continue; |
| } |
| /* No luck. We have to give up. */ |
| break; |
| } |
| |
| n_found = i; |
| return n_found; |
| } |
| |
| #endif |
| |
| |
| /*------------------------------------------------------------*/ |
| /*--- ---*/ |
| /*--- END platform-dependent unwinder worker functions ---*/ |
| /*--- ---*/ |
| /*------------------------------------------------------------*/ |
| |
| /*------------------------------------------------------------*/ |
| /*--- Exported functions. ---*/ |
| /*------------------------------------------------------------*/ |
| |
| UInt VG_(get_StackTrace) ( ThreadId tid, |
| /*OUT*/StackTrace ips, UInt max_n_ips, |
| /*OUT*/StackTrace sps, |
| /*OUT*/StackTrace fps, |
| Word first_ip_delta ) |
| { |
| /* Get the register values with which to start the unwind. */ |
| UnwindStartRegs startRegs; |
| VG_(memset)( &startRegs, 0, sizeof(startRegs) ); |
| VG_(get_UnwindStartRegs)( &startRegs, tid ); |
| |
| Addr stack_highest_word = VG_(threads)[tid].client_stack_highest_word; |
| Addr stack_lowest_word = 0; |
| |
| # if defined(VGP_x86_linux) |
| /* Nasty little hack to deal with syscalls - if libc is using its |
| _dl_sysinfo_int80 function for syscalls (the TLS version does), |
| then ip will always appear to be in that function when doing a |
| syscall, not the actual libc function doing the syscall. This |
| check sees if IP is within that function, 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. |
| |
| The function is assumed to look like this (from glibc-2.3.6 sources): |
| _dl_sysinfo_int80: |
| int $0x80 |
| ret |
| That is 3 (2+1) bytes long. We could be more thorough and check |
| the 3 bytes of the function are as expected, but I can't be |
| bothered. |
| */ |
| if (VG_(client__dl_sysinfo_int80) != 0 /* we know its address */ |
| && startRegs.r_pc >= VG_(client__dl_sysinfo_int80) |
| && startRegs.r_pc < VG_(client__dl_sysinfo_int80)+3 |
| && VG_(am_is_valid_for_client)(startRegs.r_pc, sizeof(Addr), |
| VKI_PROT_READ)) { |
| startRegs.r_pc = (ULong) *(Addr*)(UWord)startRegs.r_sp; |
| startRegs.r_sp += (ULong) sizeof(Addr); |
| } |
| # endif |
| |
| /* See if we can get a better idea of the stack limits */ |
| VG_(stack_limits)( (Addr)startRegs.r_sp, |
| &stack_lowest_word, &stack_highest_word ); |
| |
| /* Take into account the first_ip_delta. */ |
| startRegs.r_pc += (Long)(Word)first_ip_delta; |
| |
| if (0) |
| VG_(printf)("tid %d: stack_highest=0x%08lx ip=0x%010llx " |
| "sp=0x%010llx\n", |
| tid, stack_highest_word, |
| startRegs.r_pc, startRegs.r_sp); |
| |
| return VG_(get_StackTrace_wrk)(tid, ips, max_n_ips, |
| sps, fps, |
| &startRegs, |
| stack_highest_word); |
| } |
| |
| static void printIpDesc(UInt n, Addr ip, void* uu_opaque) |
| { |
| #define BUF_LEN 4096 |
| |
| static HChar buf[BUF_LEN]; |
| |
| VG_(describe_IP)(ip, buf, BUF_LEN); |
| |
| if (VG_(clo_xml)) { |
| VG_(printf_xml)(" %s\n", buf); |
| } else { |
| VG_(message)(Vg_UserMsg, " %s %s\n", ( 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_(printf_xml)(" <stack>\n"); |
| |
| VG_(apply_StackTrace)( printIpDesc, NULL, ips, n_ips ); |
| |
| if (VG_(clo_xml)) |
| VG_(printf_xml)(" </stack>\n"); |
| } |
| |
| /* Get and immediately print a StackTrace. */ |
| void VG_(get_and_pp_StackTrace) ( ThreadId tid, UInt max_n_ips ) |
| { |
| Addr ips[max_n_ips]; |
| UInt n_ips |
| = VG_(get_StackTrace)(tid, ips, max_n_ips, |
| NULL/*array to dump SP values in*/, |
| NULL/*array to dump FP values in*/, |
| 0/*first_ip_delta*/); |
| VG_(pp_StackTrace)(ips, n_ips); |
| } |
| |
| void VG_(apply_StackTrace)( |
| void(*action)(UInt n, Addr ip, void* opaque), |
| void* opaque, |
| StackTrace ips, UInt n_ips |
| ) |
| { |
| Bool main_done = False; |
| Int i = 0; |
| |
| vg_assert(n_ips > 0); |
| do { |
| Addr ip = ips[i]; |
| |
| // Stop after the first appearance of "main" or one of the other names |
| // (the appearance of which is a pretty good sign that we've gone past |
| // main without seeing it, for whatever reason) |
| if ( ! VG_(clo_show_below_main) ) { |
| Vg_FnNameKind kind = VG_(get_fnname_kind_from_IP)(ip); |
| if (Vg_FnNameMain == kind || Vg_FnNameBelowMain == kind) { |
| main_done = True; |
| } |
| } |
| |
| // Act on the ip |
| action(i, ip, opaque); |
| |
| i++; |
| } while (i < n_ips && !main_done); |
| } |
| |
| |
| /*--------------------------------------------------------------------*/ |
| /*--- end ---*/ |
| /*--------------------------------------------------------------------*/ |
