commit a56d81f4fb034eaf8fd9f9e216cf65d40a275364
author Peter Collingbourne <peter@pcc.me.uk> Mon Aug 05 20:59:25 2019 +0000
committer Peter Collingbourne <peter@pcc.me.uk> Mon Aug 05 20:59:25 2019 +0000
tree 0e0fdea619916a816a15be22864f049d90a4492f
parent 1d92925a5ad8869d208fcbfb3c093e9dee016ddc

llvm-symbolizer: Untag addresses in object files by default.

Any addresses that we pass to llvm-symbolizer are going to be untagged,
while any HWASAN instrumented globals are going to be tagged in the
symbol table. Therefore we need to untag the addresses before using them.

Differential Revision: https://reviews.llvm.org/D65769

llvm-svn: 367926

llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.cpp

diff --git a/llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.cpp b/llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.cpp
index 2765bf4..03c5c6b 100644
--- a/llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.cpp
+++ b/llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.cpp
@@ -43,10 +43,11 @@
 
 ErrorOr<std::unique_ptr<SymbolizableObjectFile>>
 SymbolizableObjectFile::create(const object::ObjectFile *Obj,
-                               std::unique_ptr<DIContext> DICtx) {
+                               std::unique_ptr<DIContext> DICtx,
+                               bool UntagAddresses) {
   assert(DICtx);
   std::unique_ptr<SymbolizableObjectFile> res(
-      new SymbolizableObjectFile(Obj, std::move(DICtx)));
+      new SymbolizableObjectFile(Obj, std::move(DICtx), UntagAddresses));
   std::unique_ptr<DataExtractor> OpdExtractor;
   uint64_t OpdAddress = 0;
   // Find the .opd (function descriptor) section if any, for big-endian
@@ -103,8 +104,10 @@
 }
 
 SymbolizableObjectFile::SymbolizableObjectFile(const ObjectFile *Obj,
-                                               std::unique_ptr<DIContext> DICtx)
-    : Module(Obj), DebugInfoContext(std::move(DICtx)) {}
+                                               std::unique_ptr<DIContext> DICtx,
+                                               bool UntagAddresses)
+    : Module(Obj), DebugInfoContext(std::move(DICtx)),
+      UntagAddresses(UntagAddresses) {}
 
 namespace {
 
@@ -172,6 +175,11 @@
   if (!SymbolAddressOrErr)
     return errorToErrorCode(SymbolAddressOrErr.takeError());
   uint64_t SymbolAddress = *SymbolAddressOrErr;
+  if (UntagAddresses) {
+    // For kernel addresses, bits 56-63 need to be set, so we sign extend bit 55
+    // into bits 56-63 instead of masking them out.
+    SymbolAddress = (int64_t(SymbolAddress) << 8) >> 8;
+  }
   if (OpdExtractor) {
     // For big-endian PowerPC64 ELF, symbols in the .opd section refer to
     // function descriptors. The first word of the descriptor is a pointer to

llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.h

diff --git a/llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.h b/llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.h
index 9cab941..b5b9793 100644
--- a/llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.h
+++ b/llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.h
@@ -31,7 +31,8 @@
 class SymbolizableObjectFile : public SymbolizableModule {
 public:
   static ErrorOr<std::unique_ptr<SymbolizableObjectFile>>
-  create(const object::ObjectFile *Obj, std::unique_ptr<DIContext> DICtx);
+  create(const object::ObjectFile *Obj, std::unique_ptr<DIContext> DICtx,
+         bool UntagAddresses);
 
   DILineInfo symbolizeCode(object::SectionedAddress ModuleOffset,
                            FunctionNameKind FNKind,
@@ -70,6 +71,7 @@
 
   const object::ObjectFile *Module;
   std::unique_ptr<DIContext> DebugInfoContext;
+  bool UntagAddresses;
 
   struct SymbolDesc {
     uint64_t Addr;
@@ -85,7 +87,8 @@
   std::vector<std::pair<SymbolDesc, StringRef>> Objects;
 
   SymbolizableObjectFile(const object::ObjectFile *Obj,
-                         std::unique_ptr<DIContext> DICtx);
+                         std::unique_ptr<DIContext> DICtx,
+                         bool UntagAddresses);
 };
 
 } // end namespace symbolize

llvm/lib/DebugInfo/Symbolize/Symbolize.cpp

diff --git a/llvm/lib/DebugInfo/Symbolize/Symbolize.cpp b/llvm/lib/DebugInfo/Symbolize/Symbolize.cpp
index 6a619f8..51aa0d7 100644
--- a/llvm/lib/DebugInfo/Symbolize/Symbolize.cpp
+++ b/llvm/lib/DebugInfo/Symbolize/Symbolize.cpp
@@ -418,8 +418,8 @@
 LLVMSymbolizer::createModuleInfo(const ObjectFile *Obj,
                                  std::unique_ptr<DIContext> Context,
                                  StringRef ModuleName) {
-  auto InfoOrErr =
-      SymbolizableObjectFile::create(Obj, std::move(Context));
+  auto InfoOrErr = SymbolizableObjectFile::create(Obj, std::move(Context),
+                                                  Opts.UntagAddresses);
   std::unique_ptr<SymbolizableModule> SymMod;
   if (InfoOrErr)
     SymMod = std::move(*InfoOrErr);