[symbolizer] Support symbol lookup

Recent versions of GNU binutils starting from 2.39 support symbol+offset
lookup in addition to the usual numeric address lookup. This change adds
symbol lookup to llvm-symbolize and llvm-addr2line.

Now llvm-symbolize behaves closer to GNU addr2line, - if the value specified
as address in command line or input stream is not a number, it is treated as
a symbol name. For example:

    llvm-symbolize --obj=abc.so func_22
    llvm-symbolize --obj=abc.so "CODE func_22"

This lookup is now supported only for functions. Specification with
offset is not supported yet.

Differential Revision: https://reviews.llvm.org/D149759

llvm/docs/CommandGuide/llvm-symbolizer.rst

@@ -14,7 +14,7 @@ DESCRIPTION
 :program:`llvm-symbolizer` reads input names and addresses from the command-line
 and prints corresponding source code locations to standard output. It can also
 symbolize logs containing :doc:`Symbolizer Markup </SymbolizerMarkupFormat>` via
-:option:`--filter-markup`.
+:option:`--filter-markup`. Addresses may be specified as numbers or symbol names.
 
 If no address is specified on the command-line, it reads the addresses from
 standard input. If no input name is specified on the command-line, but addresses
@@ -196,6 +196,17 @@ shows --relativenames.
   main
   foo/test.cpp:15:0
 
+Example 7 - Addresses as symbol names:
+
+.. code-block:: console
+
+  $ llvm-symbolizer --obj=test.elf main
+  main
+  /tmp/test.cpp:14:0
+  $ llvm-symbolizer --obj=test.elf "CODE foz"
+  foz
+  /tmp/test.h:1:0
+
 OPTIONS
 -------
 

llvm/docs/ReleaseNotes.rst

@@ -180,6 +180,8 @@ Changes to the LLVM tools
 * ``llvm-nm`` now supports the ``--line-numbers`` (``-l``) option to use
   debugging information to print symbols' filenames and line numbers.
 
+* llvm-symbolizer and llvm-addr2line now support addresses specified as symbol names.
+
 Changes to LLDB
 ---------------------------------
 

llvm/include/llvm/DebugInfo/Symbolize/DIPrinter.h

@@ -34,6 +34,7 @@ class SourceCode;
 struct Request {
   StringRef ModuleName;
   std::optional<uint64_t> Address;
+  StringRef Symbol;
 };
 
 class DIPrinter {
@@ -46,6 +47,8 @@ class DIPrinter {
   virtual void print(const Request &Request, const DIGlobal &Global) = 0;
   virtual void print(const Request &Request,
                      const std::vector<DILocal> &Locals) = 0;
+  virtual void print(const Request &Request,
+                     const std::vector<DILineInfo> &Locations) = 0;
 
   virtual bool printError(const Request &Request,
                           const ErrorInfoBase &ErrorInfo) = 0;
@@ -91,6 +94,8 @@ class PlainPrinterBase : public DIPrinter {
   void print(const Request &Request, const DIGlobal &Global) override;
   void print(const Request &Request,
              const std::vector<DILocal> &Locals) override;
+  void print(const Request &Request,
+             const std::vector<DILineInfo> &Locations) override;
 
   bool printError(const Request &Request,
                   const ErrorInfoBase &ErrorInfo) override;
@@ -141,6 +146,8 @@ class JSONPrinter : public DIPrinter {
   void print(const Request &Request, const DIGlobal &Global) override;
   void print(const Request &Request,
              const std::vector<DILocal> &Locals) override;
+  void print(const Request &Request,
+             const std::vector<DILineInfo> &Locations) override;
 
   bool printError(const Request &Request,
                   const ErrorInfoBase &ErrorInfo) override;

llvm/include/llvm/DebugInfo/Symbolize/SymbolizableModule.h

@@ -36,6 +36,9 @@ class SymbolizableModule {
   virtual std::vector<DILocal>
   symbolizeFrame(object::SectionedAddress ModuleOffset) const = 0;
 
+  virtual std::vector<object::SectionedAddress>
+  findSymbol(StringRef Symbol) const = 0;
+
   // Return true if this is a 32-bit x86 PE COFF module.
   virtual bool isWin32Module() const = 0;
 

llvm/include/llvm/DebugInfo/Symbolize/SymbolizableObjectFile.h

@@ -43,6 +43,8 @@ class SymbolizableObjectFile : public SymbolizableModule {
   DIGlobal symbolizeData(object::SectionedAddress ModuleOffset) const override;
   std::vector<DILocal>
   symbolizeFrame(object::SectionedAddress ModuleOffset) const override;
+  std::vector<object::SectionedAddress>
+  findSymbol(StringRef Symbol) const override;
 
   // Return true if this is a 32-bit x86 PE COFF module.
   bool isWin32Module() const override;

llvm/include/llvm/DebugInfo/Symbolize/Symbolize.h

@@ -104,6 +104,14 @@ class LLVMSymbolizer {
   Expected<std::vector<DILocal>>
   symbolizeFrame(ArrayRef<uint8_t> BuildID,
                  object::SectionedAddress ModuleOffset);
+
+  Expected<std::vector<DILineInfo>> findSymbol(const ObjectFile &Obj,
+                                               StringRef Symbol);
+  Expected<std::vector<DILineInfo>> findSymbol(StringRef ModuleName,
+                                               StringRef Symbol);
+  Expected<std::vector<DILineInfo>> findSymbol(ArrayRef<uint8_t> BuildID,
+                                               StringRef Symbol);
+
   void flush();
 
   // Evict entries from the binary cache until it is under the maximum size
@@ -146,6 +154,9 @@ class LLVMSymbolizer {
   Expected<std::vector<DILocal>>
   symbolizeFrameCommon(const T &ModuleSpecifier,
                        object::SectionedAddress ModuleOffset);
+  template <typename T>
+  Expected<std::vector<DILineInfo>> findSymbolCommon(const T &ModuleSpecifier,
+                                                     StringRef Symbol);
 
   Expected<SymbolizableModule *> getOrCreateModuleInfo(const ObjectFile &Obj);
 

llvm/lib/DebugInfo/Symbolize/DIPrinter.cpp

@@ -260,6 +260,17 @@ void PlainPrinterBase::print(const Request &Request,
   printFooter();
 }
 
+void PlainPrinterBase::print(const Request &Request,
+                             const std::vector<DILineInfo> &Locations) {
+  if (Locations.empty()) {
+    print(Request, DILineInfo());
+  } else {
+    for (const DILineInfo &L : Locations)
+      print(L, false);
+    printFooter();
+  }
+}
+
 bool PlainPrinterBase::printError(const Request &Request,
                                   const ErrorInfoBase &ErrorInfo) {
   ErrHandler(ErrorInfo, Request.ModuleName);
@@ -273,6 +284,8 @@ static std::string toHex(uint64_t V) {
 
 static json::Object toJSON(const Request &Request, StringRef ErrorMsg = "") {
   json::Object Json({{"ModuleName", Request.ModuleName.str()}});
+  if (!Request.Symbol.empty())
+    Json["SymName"] = Request.Symbol.str();
   if (Request.Address)
     Json["Address"] = toHex(*Request.Address);
   if (!ErrorMsg.empty())
@@ -362,6 +375,19 @@ void JSONPrinter::print(const Request &Request,
     printJSON(std::move(Json));
 }
 
+void JSONPrinter::print(const Request &Request,
+                        const std::vector<DILineInfo> &Locations) {
+  json::Array Definitions;
+  for (const DILineInfo &L : Locations)
+    Definitions.push_back(toJSON(L));
+  json::Object Json = toJSON(Request);
+  Json["Loc"] = std::move(Definitions);
+  if (ObjectList)
+    ObjectList->push_back(std::move(Json));
+  else
+    printJSON(std::move(Json));
+}
+
 bool JSONPrinter::printError(const Request &Request,
                              const ErrorInfoBase &ErrorInfo) {
   json::Object Json = toJSON(Request, ErrorInfo.message());

llvm/lib/DebugInfo/Symbolize/SymbolizableObjectFile.cpp

@@ -351,6 +351,19 @@ std::vector<DILocal> SymbolizableObjectFile::symbolizeFrame(
   return DebugInfoContext->getLocalsForAddress(ModuleOffset);
 }
 
+std::vector<object::SectionedAddress>
+SymbolizableObjectFile::findSymbol(StringRef Symbol) const {
+  std::vector<object::SectionedAddress> Result;
+  for (const SymbolDesc &Sym : Symbols) {
+    if (Sym.Name.equals(Symbol)) {
+      object::SectionedAddress A{Sym.Addr,
+                                 getModuleSectionIndexForAddress(Sym.Addr)};
+      Result.push_back(A);
+    }
+  }
+  return Result;
+}
+
 /// Search for the first occurence of specified Address in ObjectFile.
 uint64_t SymbolizableObjectFile::getModuleSectionIndexForAddress(
     uint64_t Address) const {

llvm/lib/DebugInfo/Symbolize/Symbolize.cpp

@@ -231,6 +231,50 @@ LLVMSymbolizer::symbolizeFrame(ArrayRef<uint8_t> BuildID,
   return symbolizeFrameCommon(BuildID, ModuleOffset);
 }
 
+template <typename T>
+Expected<std::vector<DILineInfo>>
+LLVMSymbolizer::findSymbolCommon(const T &ModuleSpecifier, StringRef Symbol) {
+  auto InfoOrErr = getOrCreateModuleInfo(ModuleSpecifier);
+  if (!InfoOrErr)
+    return InfoOrErr.takeError();
+
+  SymbolizableModule *Info = *InfoOrErr;
+  std::vector<DILineInfo> Result;
+
+  // A null module means an error has already been reported. Return an empty
+  // result.
+  if (!Info)
+    return Result;
+
+  for (object::SectionedAddress A : Info->findSymbol(Symbol)) {
+    DILineInfo LineInfo = Info->symbolizeCode(
+        A, DILineInfoSpecifier(Opts.PathStyle, Opts.PrintFunctions),
+        Opts.UseSymbolTable);
+    if (LineInfo.FileName != DILineInfo::BadString) {
+      if (Opts.Demangle)
+        LineInfo.FunctionName = DemangleName(LineInfo.FunctionName, Info);
+      Result.push_back(LineInfo);
+    }
+  }
+
+  return Result;
+}
+
+Expected<std::vector<DILineInfo>>
+LLVMSymbolizer::findSymbol(const ObjectFile &Obj, StringRef Symbol) {
+  return findSymbolCommon(Obj, Symbol);
+}
+
+Expected<std::vector<DILineInfo>>
+LLVMSymbolizer::findSymbol(StringRef ModuleName, StringRef Symbol) {
+  return findSymbolCommon(ModuleName.str(), Symbol);
+}
+
+Expected<std::vector<DILineInfo>>
+LLVMSymbolizer::findSymbol(ArrayRef<uint8_t> BuildID, StringRef Symbol) {
+  return findSymbolCommon(BuildID, Symbol);
+}
+
 void LLVMSymbolizer::flush() {
   ObjectForUBPathAndArch.clear();
   LRUBinaries.clear();

llvm/test/tools/llvm-symbolizer/Inputs/addr.inp

@@ -1,3 +1,3 @@
-some text
+something not a valid address
 0x40054d
-some text2
+some text possibly a symbol

llvm/test/tools/llvm-symbolizer/Inputs/discrim.inp

@@ -5,4 +5,4 @@ some text
 0x4005b9
 0x4005ce
 0x4005d4
-some more text
+another text

llvm/test/tools/llvm-symbolizer/Inputs/symbols.h

@@ -0,0 +1,19 @@
+// This file is a part of sources used to build `symbols.so`, which is used to
+// test symbol location search made by llvm-symbolizer.
+//
+// Build instructions:
+// $ mkdir /tmp/dbginfo
+// $ cp symbols.h symbols.part1.cpp symbols.part2.cpp symbols.part3.c symbols.part4.c /tmp/dbginfo/
+// $ cd /tmp/dbginfo
+// $ gcc -osymbols.so -shared -fPIC -g symbols.part1.cpp symbols.part2.cpp symbols.part3.c symbols.part4.c
+
+
+extern "C" {
+extern int global_01;
+int func_01();
+int func_02(int);
+}
+
+template<typename T> T func_03(T x) {
+  return x + T(1);
+}

llvm/test/tools/llvm-symbolizer/Inputs/symbols.part1.cpp

@@ -0,0 +1,25 @@
+#include "symbols.h"
+
+int global_01 = 22;
+
+int static static_var = 0;
+
+static int static_func_01(int x) {
+  static_var = x;
+  return global_01;
+}
+
+int func_01() {
+  int res = 1;
+  return res + static_func_01(22);
+}
+
+int func_04() {
+  static_var = 0;
+  return 22;
+}
+
+int func_04(int x) {
+  int res = static_var;
+  return res + func_03(x);
+}

llvm/test/tools/llvm-symbolizer/Inputs/symbols.part2.cpp

@@ -0,0 +1,18 @@
+#include "symbols.h"
+
+int static static_var = 4;
+
+static int static_func_01(int x) {
+  static_var--;
+  return x;
+}
+
+int func_02(int x) {
+  static_var = x;
+  return static_func_01(x);
+}
+
+int func_05(int x) {
+  int res = static_var;
+  return res + func_03(x);
+}

llvm/test/tools/llvm-symbolizer/Inputs/symbols.part3.c

@@ -0,0 +1,12 @@
+static int static_func(int);
+static int static_var = 0;
+
+int static_func(int x) {
+  static_var++;
+  return static_var + x;
+}
+
+int func_06(int x) {
+  return static_func(x);
+}
+

llvm/test/tools/llvm-symbolizer/Inputs/symbols.part4.c

@@ -0,0 +1,13 @@
+static int static_func(int);
+static int static_var = 5;
+
+int static_func(int x) {
+  static_var++;
+  return static_var + x;
+}
+
+int func_07(int x) {
+  static_var++;
+  return static_func(x);
+}
+

llvm/test/tools/llvm-symbolizer/output-style-json-code.test

@@ -25,39 +25,44 @@
 # RUN: llvm-symbolizer --output-style=JSON --no-inlines -e %p/Inputs/addr.exe < %p/Inputs/addr.inp | \
 # RUN:   FileCheck %s --check-prefix=NO-INLINES --strict-whitespace --match-full-lines --implicit-check-not={{.}}
 ## Invalid first argument before any valid one.
-# NO-INLINES:{"ModuleName":"{{.*}}/Inputs/addr.exe","Symbol":[{"Column":0,"Discriminator":0,"FileName":"","FunctionName":"","Line":0,"StartAddress":"","StartFileName":"","StartLine":0}]}
+# NO-INLINES:{"Loc":[],"ModuleName":"{{.*}}/Inputs/addr.exe","SymName":"something"}
 ## Resolve valid address.
 # NO-INLINES-NEXT:{"Address":"0x40054d","ModuleName":"{{.*}}/Inputs/addr.exe","Symbol":[{"Column":3,"Discriminator":0,"FileName":"/tmp{{/|\\\\}}x.c","FunctionName":"main","Line":3,"StartAddress":"0x400540","StartFileName":"/tmp{{/|\\\\}}x.c","StartLine":2}]}
 ## Invalid argument after a valid one.
-# NO-INLINES-NEXT:{"ModuleName":"{{.*}}/Inputs/addr.exe","Symbol":[{"Column":0,"Discriminator":0,"FileName":"","FunctionName":"","Line":0,"StartAddress":"","StartFileName":"","StartLine":0}]}
+# NO-INLINES-NEXT:{"Loc":[],"ModuleName":"{{.*}}/Inputs/addr.exe","SymName":"some"}
 
 ## This test case is testing stdin input, inlines by default.
 # RUN: llvm-symbolizer --output-style=JSON -e %p/Inputs/addr.exe < %p/Inputs/addr.inp | \
 # RUN:   FileCheck %s --check-prefix=INLINE --strict-whitespace --match-full-lines --implicit-check-not={{.}}
 ## Invalid first argument before any valid one.
-# INLINE:{"ModuleName":"{{.*}}/Inputs/addr.exe","Symbol":[{"Column":0,"Discriminator":0,"FileName":"","FunctionName":"","Line":0,"StartAddress":"","StartFileName":"","StartLine":0}]}
+# INLINE:{"Loc":[],"ModuleName":"{{.*}}/Inputs/addr.exe","SymName":"something"}
 ## Resolve valid address.
 # INLINE-NEXT:{"Address":"0x40054d","ModuleName":"{{.*}}/Inputs/addr.exe","Symbol":[{"Column":3,"Discriminator":0,"FileName":"/tmp{{/|\\\\}}x.c","FunctionName":"inctwo","Line":3,"StartAddress":"0x400540","StartFileName":"/tmp{{/|\\\\}}x.c","StartLine":2},{"Column":0,"Discriminator":0,"FileName":"/tmp{{/|\\\\}}x.c","FunctionName":"inc","Line":7,"StartAddress":"0x400540","StartFileName":"/tmp{{/|\\\\}}x.c","StartLine":6},{"Column":0,"Discriminator":0,"FileName":"/tmp{{/|\\\\}}x.c","FunctionName":"main","Line":14,"StartAddress":"0x400540","StartFileName":"/tmp{{/|\\\\}}x.c","StartLine":12}]}
 ## Invalid argument after a valid one.
-# INLINE-NEXT:{"ModuleName":"{{.*}}/Inputs/addr.exe","Symbol":[{"Column":0,"Discriminator":0,"FileName":"","FunctionName":"","Line":0,"StartAddress":"","StartFileName":"","StartLine":0}]}
+# INLINE-NEXT:{"Loc":[],"ModuleName":"{{.*}}/Inputs/addr.exe","SymName":"some"}
 
 ## Also check the last test case with llvm-adr2line.
 ## The expected result is the same with -f -i.
 # RUN: llvm-addr2line --output-style=JSON -f -i -e %p/Inputs/addr.exe < %p/Inputs/addr.inp | \
 # RUN:   FileCheck %s --check-prefix=INLINE-A2L --strict-whitespace --match-full-lines --implicit-check-not={{.}}
 ## Invalid first argument before any valid one.
-# INLINE-A2L:{"ModuleName":"{{.*}}/Inputs/addr.exe","Symbol":[{"Column":0,"Discriminator":0,"FileName":"","FunctionName":"","Line":0,"StartAddress":"","StartFileName":"","StartLine":0}]}
+# INLINE-A2L:{"Loc":[],"ModuleName":"{{.*}}/Inputs/addr.exe","SymName":"something"}
 ## Resolve valid address.
 # INLINE-A2L-NEXT:{"Address":"0x40054d","ModuleName":"{{.*}}/Inputs/addr.exe","Symbol":[{"Column":3,"Discriminator":0,"FileName":"/tmp{{/|\\\\}}x.c","FunctionName":"inctwo","Line":3,"StartAddress":"0x400540","StartFileName":"/tmp{{/|\\\\}}x.c","StartLine":2},{"Column":0,"Discriminator":0,"FileName":"/tmp{{/|\\\\}}x.c","FunctionName":"inc","Line":7,"StartAddress":"0x400540","StartFileName":"/tmp{{/|\\\\}}x.c","StartLine":6},{"Column":0,"Discriminator":0,"FileName":"/tmp{{/|\\\\}}x.c","FunctionName":"main","Line":14,"StartAddress":"0x400540","StartFileName":"/tmp{{/|\\\\}}x.c","StartLine":12}]}
 ## Invalid argument after a valid one.
-# INLINE-A2L-NEXT:{"ModuleName":"{{.*}}/Inputs/addr.exe","Symbol":[{"Column":0,"Discriminator":0,"FileName":"","FunctionName":"","Line":0,"StartAddress":"","StartFileName":"","StartLine":0}]}
+# INLINE-A2L:{"Loc":[],"ModuleName":"{{.*}}/Inputs/addr.exe","SymName":"some"}
 
 ## Note llvm-addr2line without -f does not print the function name in JSON too.
 # RUN: llvm-addr2line --output-style=JSON -i -e %p/Inputs/addr.exe < %p/Inputs/addr.inp | \
 # RUN:   FileCheck %s --check-prefix=NO-FUNC-A2L --strict-whitespace --match-full-lines --implicit-check-not={{.}}
 ## Invalid first argument before any valid one.
-# NO-FUNC-A2L:{"ModuleName":"{{.*}}/Inputs/addr.exe","Symbol":[{"Column":0,"Discriminator":0,"FileName":"","FunctionName":"","Line":0,"StartAddress":"","StartFileName":"","StartLine":0}]}
+# NO-FUNC-A2L:{"Loc":[],"ModuleName":"{{.*}}/Inputs/addr.exe","SymName":"something"}
 ## Resolve valid address.
 # NO-FUNC-A2L-NEXT:{"Address":"0x40054d","ModuleName":"{{.*}}/Inputs/addr.exe","Symbol":[{"Column":3,"Discriminator":0,"FileName":"/tmp{{/|\\\\}}x.c","FunctionName":"","Line":3,"StartAddress":"0x400540","StartFileName":"/tmp{{/|\\\\}}x.c","StartLine":2},{"Column":0,"Discriminator":0,"FileName":"/tmp{{/|\\\\}}x.c","FunctionName":"","Line":7,"StartAddress":"0x400540","StartFileName":"/tmp{{/|\\\\}}x.c","StartLine":6},{"Column":0,"Discriminator":0,"FileName":"/tmp{{/|\\\\}}x.c","FunctionName":"","Line":14,"StartAddress":"0x400540","StartFileName":"/tmp{{/|\\\\}}x.c","StartLine":12}]}
 ## Invalid argument after a valid one.
-# NO-FUNC-A2L-NEXT:{"ModuleName":"{{.*}}/Inputs/addr.exe","Symbol":[{"Column":0,"Discriminator":0,"FileName":"","FunctionName":"","Line":0,"StartAddress":"","StartFileName":"","StartLine":0}]}
+# NO-FUNC-A2L-NEXT:{"Loc":[],"ModuleName":"{{.*}}/Inputs/addr.exe","SymName":"some"}
+
+## When a module offset is specified by a symbol, more than one source location can be found.
+# RUN: llvm-symbolizer --output-style=JSON --no-inlines -e %p/Inputs/symbols.so "static_func" | \
+# RUN:   FileCheck %s --check-prefix=MULTIPLE --strict-whitespace --match-full-lines --implicit-check-not={{.}}
+# MULTIPLE:[{"Loc":[{"Column":24,"Discriminator":0,"FileName":"/tmp/dbginfo{{/|\\\\}}symbols.part3.c","FunctionName":"static_func","Line":4,"StartAddress":"0x121d","StartFileName":"/tmp/dbginfo{{/|\\\\}}symbols.part3.c","StartLine":4},{"Column":24,"Discriminator":0,"FileName":"/tmp/dbginfo{{/|\\\\}}symbols.part4.c","FunctionName":"static_func","Line":4,"StartAddress":"0x125f","StartFileName":"/tmp/dbginfo{{/|\\\\}}symbols.part4.c","StartLine":4}],"ModuleName":"{{.*}}Inputs/symbols.so","SymName":"static_func"}]