Hi Jakub,
Can you please an updated patch in the attachment?
On Mon, Nov 18, 2013 at 8:23 PM, Jakub Jelinek <ja...@redhat.com> wrote:
> On Mon, Nov 18, 2013 at 07:50:33PM +0400, Alexey Samsonov wrote:
>> On Mon, Nov 18, 2013 at 7:49 PM, Alexey Samsonov <samso...@google.com> wrote:
>> Unfortunately, recently there were a few enhancements to
>> sanitizer_symbolizer_posix_libcdep.cc (and friends),
>> in LLVM trunk, and now it looks different from gcc version (apparently, the
>> changes were committed
>> after the merge to gcc happened, I should have pointed this out earlier,
>> sorry).
>>
>> Kostya (or Jakub), is it possible to somehow pick up the changes? Otherwise
>> this patch can't go in ASan runtime
>> in gcc - the code will significantly diverge.
>
> Here is an (untested) forward port of the patch to what is in llvm svn right
> now. The unpatched code always had either internal_symbolizer_ != NULL, or
> external_symbolizer_ != NULL, or both NULL, but not both set. The patch
> just adds a third variant, libbacktrace_symbolizer_, again, at most one
> of the 3 will be non-NULL, and the priorities are that internal_symbolizer_
> has highest priority, then libbacktrace (if available/usable), then the
> external one.
>
> --- sanitizer_symbolizer_posix_libcdep.cc.jj 2013-11-12 19:35:30.000000000
> +0100
> +++ sanitizer_symbolizer_posix_libcdep.cc 2013-11-18 17:16:03.202643957
> +0100
> @@ -27,6 +27,16 @@
> #include <sys/wait.h>
> #include <unistd.h>
>
> +#ifdef SANITIZER_LIBBACKTRACE
> +#include "backtrace-supported.h"
> +#if SANITIZER_LINUX && BACKTRACE_SUPPORTED \
> + && !BACKTRACE_USES_MALLOC && BACKTRACE_SUPPORTS_THREADS
> +#include "backtrace.h"
> +#else
> +#undef SANITIZER_LIBBACKTRACE
> +#endif
> +#endif
> +
> // C++ demangling function, as required by Itanium C++ ABI. This is weak,
> // because we do not require a C++ ABI library to be linked to a program
> // using sanitizers; if it's not present, we'll just use the mangled name.
> @@ -364,12 +374,124 @@ class InternalSymbolizer {
>
> #endif // SANITIZER_SUPPORTS_WEAK_HOOKS
>
> +#if SANITIZER_LIBBACKTRACE
> +namespace {
> +
> +struct SymbolizeCodeData {
> + AddressInfo *frames;
> + uptr n_frames;
> + uptr max_frames;
max_frames is not used anywhere.
> + const char *module_name;
> + uptr module_offset;
> +};
> +
> +extern "C" {
why do you need extern "C" here?
> +
> +static int SymbolizeCodePCInfoCallback(void *vdata, uintptr_t addr,
> + const char *filename, int lineno,
> + const char *function) {
> + SymbolizeCodeData *cdata = (SymbolizeCodeData *)vdata;
> + if (function) {
> + AddressInfo *info = &cdata->frames[cdata->n_frames++];
> + info->Clear();
> + info->FillAddressAndModuleInfo(addr, cdata->module_name,
> cdata->module_offset);
> + info->function = internal_strdup(function);
> + if (filename)
> + info->file = internal_strdup(filename);
> + info->line = lineno;
> + }
> + return 0;
> +}
> +
> +static void SymbolizeCodeCallback(void *vdata, uintptr_t addr,
> + const char *symname, uintptr_t) {
> + SymbolizeCodeData *cdata = (SymbolizeCodeData *)vdata;
> + if (symname) {
> + AddressInfo *info = &cdata->frames[0];
> + info->Clear();
> + info->FillAddressAndModuleInfo(addr, cdata->module_name,
> cdata->module_offset);
> + info->function = internal_strdup(symname);
> + cdata->n_frames = 1;
> + }
> +}
> +
> +static void SymbolizeDataCallback(void *vdata, uintptr_t,
> + const char *symname, uintptr_t symval) {
> + DataInfo *info = (DataInfo *)vdata;
> + if (symname && symval) {
> + info->name = internal_strdup(symname);
> + info->start = symval;
> + }
> +}
> +
> +static void ErrorCallback(void *, const char *, int) {
> +}
> +
> +}
> +
> +}
> +
> +class LibbacktraceSymbolizer {
> + public:
> + static LibbacktraceSymbolizer *get(LowLevelAllocator *alloc) {
> + backtrace_state *state
> + = backtrace_create_state("/proc/self/exe", 1, ErrorCallback, NULL);
You may want to use ReadBinaryName() here (in case it was cached
earlier, e.g. before
we create a sandbox).
> + if (!state)
> + return 0;
> + return new(*alloc) LibbacktraceSymbolizer(state);
> + }
> +
> + uptr SymbolizeCode(uptr addr, AddressInfo *frames, uptr max_frames,
> + const char *module_name, uptr module_offset) {
> + SymbolizeCodeData data;
> + data.frames = frames;
> + data.n_frames = 0;
> + data.max_frames = max_frames;
> + data.module_name = module_name;
> + data.module_offset = module_offset;
> + backtrace_pcinfo(state_, addr, SymbolizeCodePCInfoCallback,
> ErrorCallback,
> + &data);
> + if (data.n_frames)
> + return data.n_frames;
> + backtrace_syminfo(state_, addr, SymbolizeCodeCallback, ErrorCallback,
> &data);
> + return data.n_frames;
> + }
> +
> + void SymbolizeData(DataInfo *info) {
> + backtrace_syminfo(state_, info->address, SymbolizeDataCallback,
> + ErrorCallback, info);
> + }
> +
> + private:
> + LibbacktraceSymbolizer(backtrace_state *state) : state_(state) { }
> +
> + backtrace_state *state_; // Leaked.
> +};
> +#else
> +class LibbacktraceSymbolizer {
> + public:
> + static LibbacktraceSymbolizer *get(LowLevelAllocator *) {
> + return 0;
> + }
> +
> + uptr SymbolizeCode(uptr addr, AddressInfo *frames, uptr max_frames,
> + const char *module_name, uptr module_offset) {
> + return 0;
> + }
> +
> + void SymbolizeData(DataInfo *info) {
> + }
> +};
> +#endif
Looks like Libbacktrace symbolizer is now wrapped in a straightforward
interface. Could you please
move it it sanitizer_symbolizer_libbacktrace.{h,cc}, and keep changes
to sanitizer_symbolizer_posix_libcdep.cc
minimal?
> +
> class POSIXSymbolizer : public Symbolizer {
> public:
> POSIXSymbolizer(ExternalSymbolizer *external_symbolizer,
> + LibbacktraceSymbolizer *libbacktrace_symbolizer,
> InternalSymbolizer *internal_symbolizer)
> : Symbolizer(),
> external_symbolizer_(external_symbolizer),
> + libbacktrace_symbolizer_(libbacktrace_symbolizer),
> internal_symbolizer_(internal_symbolizer) {}
>
> uptr SymbolizeCode(uptr addr, AddressInfo *frames, uptr max_frames) {
> @@ -381,7 +503,18 @@ class POSIXSymbolizer : public Symbolize
> return 0;
> const char *module_name = module->full_name();
> uptr module_offset = addr - module->base_address();
> - const char *str = SendCommand(false, module_name, module_offset);
> + const char *str = 0;
> + if (libbacktrace_symbolizer_)
> + {
> + uptr ret
> + = libbacktrace_symbolizer_->SymbolizeCode(addr, frames, max_frames,
> + module_name,
> + module_offset);
> + if (ret)
> + return ret;
> + }
> + else
> + str = SendCommand(false, module_name, module_offset);
> if (str == 0) {
> // External symbolizer was not initialized or failed. Fill only data
> // about module name and offset.
> @@ -444,6 +577,10 @@ class POSIXSymbolizer : public Symbolize
> info->address = addr;
> info->module = internal_strdup(module_name);
> info->module_offset = module_offset;
> + if (libbacktrace_symbolizer_) {
> + libbacktrace_symbolizer_->SymbolizeData(info);
> + return true;
> + }
> const char *str = SendCommand(true, module_name, module_offset);
> if (str == 0)
> return true;
> @@ -455,7 +594,9 @@ class POSIXSymbolizer : public Symbolize
> }
>
> bool IsAvailable() {
> - return internal_symbolizer_ != 0 || external_symbolizer_ != 0;
> + return internal_symbolizer_ != 0 ||
> + libbacktrace_symbolizer_ != 0 ||
> + external_symbolizer_ != 0;
> }
>
> bool IsExternalAvailable() {
> @@ -573,14 +714,19 @@ class POSIXSymbolizer : public Symbolize
>
> ExternalSymbolizer *external_symbolizer_; // Leaked.
> InternalSymbolizer *const internal_symbolizer_; // Leaked.
> + LibbacktraceSymbolizer *libbacktrace_symbolizer_; // Leaked.
> };
>
> Symbolizer *Symbolizer::PlatformInit(const char *path_to_external) {
> InternalSymbolizer* internal_symbolizer =
> InternalSymbolizer::get(&symbolizer_allocator_);
> + LibbacktraceSymbolizer* libbacktrace_symbolizer = 0;
> ExternalSymbolizer *external_symbolizer = 0;
>
> - if (!internal_symbolizer) {
> + if (!internal_symbolizer)
> + libbacktrace_symbolizer =
> + LibbacktraceSymbolizer::get(&symbolizer_allocator_);
> + if (!internal_symbolizer && !libbacktrace_symbolizer) {
> if (!path_to_external || path_to_external[0] == '\0')
> path_to_external = FindPathToBinary("llvm-symbolizer");
>
> @@ -593,7 +739,8 @@ Symbolizer *Symbolizer::PlatformInit(con
> }
>
> return new(symbolizer_allocator_)
> - POSIXSymbolizer(external_symbolizer, internal_symbolizer);
> + POSIXSymbolizer(external_symbolizer, libbacktrace_symbolizer,
> + internal_symbolizer);
> }
>
> } // namespace __sanitizer
>
>
> Jakub
--
Alexey Samsonov, MSK
