[compiler-rt] r194805 - [Sanitizer] Make slow unwinder on Linux more robust

[Alexey Samsonov]

Author: samsonov
Date: Fri Nov 15 04:57:56 2013
New Revision: 194805

URL: http://llvm.org/viewvc/llvm-project?rev=194805&view=rev
Log:
[Sanitizer] Make slow unwinder on Linux more robust

Modified:
    compiler-rt/trunk/lib/asan/lit_tests/TestCases/double-free.cc
    compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux_libcdep.cc
    compiler-rt/trunk/lib/sanitizer_common/sanitizer_stacktrace.cc
    compiler-rt/trunk/lib/sanitizer_common/sanitizer_stacktrace.h

Modified: compiler-rt/trunk/lib/asan/lit_tests/TestCases/double-free.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/lit_tests/TestCases/double-free.cc?rev=194805&r1=194804&r2=194805&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/lit_tests/TestCases/double-free.cc (original)
+++ compiler-rt/trunk/lib/asan/lit_tests/TestCases/double-free.cc Fri Nov 15 04:57:56 2013
@@ -14,10 +14,12 @@ int main(int argc, char **argv) {
   free(x);
   free(x + argc - 1);  // BOOM
   // CHECK: AddressSanitizer: attempting double-free{{.*}}in thread T0
-  // CHECK: double-free.cc:[[@LINE-2]]
+  // CHECK: #0 0x{{.*}} in {{.*}}free
+  // CHECK: #1 0x{{.*}} in main {{.*}}double-free.cc:[[@LINE-3]]
   // CHECK: freed by thread T0 here:
-  // MALLOC-CTX: double-free.cc:[[@LINE-5]]
+  // MALLOC-CTX: #0 0x{{.*}} in {{.*}}free
+  // MALLOC-CTX: #1 0x{{.*}} in main {{.*}}double-free.cc:[[@LINE-7]]
   // CHECK: allocated by thread T0 here:
-  // MALLOC-CTX: double-free.cc:[[@LINE-10]]
+  // MALLOC-CTX: double-free.cc:[[@LINE-12]]
   return res;
 }

Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux_libcdep.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux_libcdep.cc?rev=194805&r1=194804&r2=194805&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux_libcdep.cc (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_linux_libcdep.cc Fri Nov 15 04:57:56 2013
@@ -161,7 +161,7 @@ void StackTrace::SlowUnwindStack(uptr pc
   UnwindTraceArg arg = {this, Min(max_depth + 1, kStackTraceMax)};
   _Unwind_Backtrace(Unwind_Trace, &arg);
   // We need to pop a few frames so that pc is on top.
-  uptr to_pop = LocatePcInTrace(pc, 6);
+  uptr to_pop = LocatePcInTrace(pc);
   // trace[0] belongs to the current function so we always pop it.
   if (to_pop == 0)
     to_pop = 1;

Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_stacktrace.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_stacktrace.cc?rev=194805&r1=194804&r2=194805&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_stacktrace.cc (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_stacktrace.cc Fri Nov 15 04:57:56 2013
@@ -158,12 +158,11 @@ static bool MatchPc(uptr cur_pc, uptr tr
   return cur_pc - trace_pc <= threshold || trace_pc - cur_pc <= threshold;
 }
 
-uptr
-StackTrace::LocatePcInTrace(uptr pc, uptr max_pc_depth) {
+uptr StackTrace::LocatePcInTrace(uptr pc) {
   // Use threshold to find PC in stack trace, as PC we want to unwind from may
   // slightly differ from return address in the actual unwinded stack trace.
-  const int kPcThreshold = 64;
-  for (uptr i = 0; i < max_pc_depth && i < size; ++i) {
+  const int kPcThreshold = 96;
+  for (uptr i = 0; i < size; ++i) {
     if (MatchPc(pc, trace[i], kPcThreshold))
       return i;
   }

Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_stacktrace.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_stacktrace.h?rev=194805&r1=194804&r2=194805&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_stacktrace.h (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_stacktrace.h Fri Nov 15 04:57:56 2013
@@ -69,7 +69,7 @@ struct StackTrace {
                        uptr max_depth);
   void SlowUnwindStack(uptr pc, uptr max_depth);
   void PopStackFrames(uptr count);
-  uptr LocatePcInTrace(uptr pc, uptr max_pc_depth = -1);
+  uptr LocatePcInTrace(uptr pc);
 };
 
 }  // namespace __sanitizer