[sanstats] Print the correct line information.

The instrumentation tracks the return address and not that of the
call so we remove one to compensate. Thanks for Peter Collingbourne
for confirming the analysis of the problem.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307871 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/tools/sanstats/Inputs/debuginfo.stats b/test/tools/sanstats/Inputs/debuginfo.stats
new file mode 100644 (file)
index 0000000..45de79b
Binary files /dev/null and b/test/tools/sanstats/Inputs/debuginfo.stats differ

diff --git a/test/tools/sanstats/debuginfo.test b/test/tools/sanstats/debuginfo.test
new file mode 100644 (file)
index 0000000..6585ff7
--- /dev/null
+++ b/test/tools/sanstats/debuginfo.test
@@ -0,0 +1,4 @@
+# RUN: sanstats %p/Inputs/debuginfo.stats | FileCheck %s
+
+# CHECK: stats.cpp:23 vcall.cfi cfi-vcall 37
+# CHECK: stats.cpp:28 nvcall.cfi cfi-nvcall 51

diff --git a/tools/sanstats/sanstats.cpp b/tools/sanstats/sanstats.cpp
index b2216eab119e124d7887bb5b139d061e88cd143a..4463c0f0e48c428c0fed06a92e866e8ea212441d 100644 (file)
--- a/tools/sanstats/sanstats.cpp
+++ b/tools/sanstats/sanstats.cpp
@@ -76,8 +76,11 @@ const char *ReadModule(char SizeofPtr, const char *Begin, const char *End) {
     if (Begin == End)
       return nullptr;
 
+    // As the instrumentation tracks the return address and not
+    // the address of the call to `__sanitizer_stats_report` we
+    // remove one from the address to get the correct DI.
     if (Expected<DILineInfo> LineInfo =
-            Symbolizer.symbolizeCode(Filename, Addr)) {
+            Symbolizer.symbolizeCode(Filename, Addr - 1)) {
       llvm::outs() << LineInfo->FileName << ':' << LineInfo->Line << ' '
                    << LineInfo->FunctionName << ' ';
     } else {