[Symbolizer][Debuginfo] Add debuginfod client to llvm-symbolizer.

Adds a fallback to use the debuginfod client library (386655) in `findDebugBinary`.
Fixed a cast of Erorr::success() to Expected<> in debuginfod library.
Added Debuginfod to Symbolize deps in gn.
Adds new symbolizer symbols to `global_symbols.txt`.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D113717

compiler-rt/lib/sanitizer_common/symbolizer/scripts/global_symbols.txt

@@ -71,6 +71,10 @@ fputc U
 free U
 freelocale U
 fwrite U
+getCachedOrDownloadDebuginfoENS_8ArrayRef T
+getDefaultDebuginfodCacheDirectory T
+getDefaultDebuginfodTimeout T
+getDefaultDebuginfodUrls T
 getc U
 getcwd U
 getenv U

llvm/include/llvm/Debuginfod/HTTPClient.h

@@ -79,13 +79,14 @@ class BufferedHTTPResponseHandler final : public HTTPResponseHandler {
 class HTTPClient {
 #ifdef LLVM_ENABLE_CURL
   void *Curl = nullptr;
-  static bool IsInitialized;
 #endif
 
 public:
   HTTPClient();
   ~HTTPClient();
 
+  static bool IsInitialized;
+
   /// Returns true only if LLVM has been compiled with a working HTTPClient.
   static bool isAvailable();
 

llvm/lib/DebugInfo/Symbolize/CMakeLists.txt

@@ -9,6 +9,7 @@ add_llvm_component_library(LLVMSymbolize
   LINK_COMPONENTS
   DebugInfoDWARF
   DebugInfoPDB
+  Debuginfod
   Object
   Support
   Demangle

llvm/lib/DebugInfo/Symbolize/Symbolize.cpp

@@ -20,6 +20,7 @@
 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
 #include "llvm/DebugInfo/PDB/PDB.h"
 #include "llvm/DebugInfo/PDB/PDBContext.h"
+#include "llvm/Debuginfod/Debuginfod.h"
 #include "llvm/Demangle/Demangle.h"
 #include "llvm/Object/COFF.h"
 #include "llvm/Object/MachO.h"
@@ -384,7 +385,14 @@ bool findDebugBinary(const std::vector<std::string> &DebugFileDirectory,
       }
     }
   }
-  return false;
+  // Try debuginfod client cache and known servers.
+  Expected<std::string> PathOrErr = getCachedOrDownloadDebuginfo(BuildID);
+  if (!PathOrErr) {
+    consumeError(PathOrErr.takeError());
+    return false;
+  }
+  Result = *PathOrErr;
+  return true;
 }
 
 } // end anonymous namespace

llvm/lib/Debuginfod/Debuginfod.cpp

@@ -139,6 +139,13 @@ Expected<std::string> getCachedOrDownloadArtifact(
     return createStringError(errc::io_error,
                              "No working HTTP client is available.");
 
+  if (!HTTPClient::IsInitialized)
+    return createStringError(
+        errc::io_error,
+        "A working HTTP client is available, but it is not initialized. To "
+        "allow Debuginfod to make HTTP requests, call HTTPClient::initialize() "
+        "at the beginning of main.");
+
   HTTPClient Client;
   Client.setTimeout(Timeout);
   for (StringRef ServerUrl : DebuginfodUrls) {
@@ -157,7 +164,7 @@ Expected<std::string> getCachedOrDownloadArtifact(
     // file cache.
     Expected<std::unique_ptr<CachedFileStream>> FileStreamOrErr =
         CacheAddStream(Task);
-    if (FileStreamOrErr)
+    if (!FileStreamOrErr)
       return FileStreamOrErr.takeError();
     std::unique_ptr<CachedFileStream> &FileStream = *FileStreamOrErr;
     if (!Response.Body)

llvm/lib/Debuginfod/HTTPClient.cpp

@@ -72,6 +72,14 @@ Error BufferedHTTPResponseHandler::handleStatusCode(unsigned Code) {
   return Error::success();
 }
 
+bool HTTPClient::IsInitialized = false;
+
+class HTTPClientCleanup {
+public:
+  ~HTTPClientCleanup() { HTTPClient::cleanup(); }
+};
+static const HTTPClientCleanup Cleanup;
+
 Expected<HTTPResponseBuffer> HTTPClient::perform(const HTTPRequest &Request) {
   BufferedHTTPResponseHandler Handler;
   if (Error Err = perform(Request, Handler))
@@ -88,8 +96,6 @@ Expected<HTTPResponseBuffer> HTTPClient::get(StringRef Url) {
 
 bool HTTPClient::isAvailable() { return true; }
 
-bool HTTPClient::IsInitialized = false;
-
 void HTTPClient::initialize() {
   if (!IsInitialized) {
     curl_global_init(CURL_GLOBAL_ALL);

llvm/test/tools/llvm-symbolizer/debuginfod.test

@@ -0,0 +1,27 @@
+# This test uses the local debuginfod cache to test the symbolizer integration
+# with the debuginfod client.
+RUN: rm -rf %t
+RUN: mkdir %t
+
+# Produce a stripped copy of the input binary addr.exe
+RUN: llvm-objcopy --strip-debug %p/Inputs/addr.exe %t/addr.exe
+
+# Symbolizing the stripped binary should fail.
+RUN: env DEBUGINFOD_CACHE_PATH=%t llvm-symbolizer --print-address \
+RUN:   --obj=%t/addr.exe 0x40054d | FileCheck %s --check-prefix=NOTFOUND
+NOTFOUND: 0x40054d
+NOTFOUND-NEXT: main
+NOTFOUND-NEXT: ??:0:0
+
+# Use llvm-objcopy to write the debuginfo of the addr.exe binary to an
+# appropriately-named file in the llvm debuginfod cache. The filename is
+# determined by the debuginfod client's caching scheme, so it is manually
+# specified here as llvmcache-98...19
+RUN: llvm-objcopy --keep-section=.debug_info %p/Inputs/addr.exe \
+RUN:   %t/llvmcache-9800707741016212219
+
+# The symbolizer should call the debuginfod client library, which finds the
+# debuginfo placed in the cache, enabling symbolization of the address.
+RUN: env DEBUGINFOD_CACHE_PATH=%t llvm-symbolizer \
+RUN:   --obj=%t/addr.exe 0x40054d | FileCheck %s --check-prefix=FOUND
+FOUND: {{[/\]+}}tmp{{[/\]+}}x.c:14:0

llvm/tools/llvm-symbolizer/CMakeLists.txt

@@ -10,6 +10,7 @@ add_public_tablegen_target(SymbolizerOptsTableGen)
 set(LLVM_LINK_COMPONENTS
   DebugInfoDWARF
   DebugInfoPDB
+  Debuginfod
   Demangle
   Object
   Option

llvm/tools/llvm-symbolizer/llvm-symbolizer.cpp

@@ -19,6 +19,7 @@
 #include "llvm/Config/config.h"
 #include "llvm/DebugInfo/Symbolize/DIPrinter.h"
 #include "llvm/DebugInfo/Symbolize/Symbolize.h"
+#include "llvm/Debuginfod/HTTPClient.h"
 #include "llvm/Option/Arg.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Option/Option.h"
@@ -261,6 +262,8 @@ static FunctionNameKind decideHowToPrintFunctions(const opt::InputArgList &Args,
 
 int main(int argc, char **argv) {
   InitLLVM X(argc, argv);
+  // The HTTPClient must be initialized for use by the debuginfod client.
+  HTTPClient::initialize();
   sys::InitializeCOMRAII COM(sys::COMThreadingMode::MultiThreaded);
 
   bool IsAddr2Line = sys::path::stem(argv[0]).contains("addr2line");

llvm/utils/gn/secondary/llvm/lib/DebugInfo/Symbolize/BUILD.gn

@@ -4,6 +4,7 @@ static_library("Symbolize") {
     "//llvm/include/llvm/Config:config",
     "//llvm/lib/DebugInfo/DWARF",
     "//llvm/lib/DebugInfo/PDB",
+    "//llvm/lib/Debuginfod",
     "//llvm/lib/Demangle",
     "//llvm/lib/Object",
     "//llvm/lib/Support",