Index: llvm/lib/DebugInfo/Symbolize/CMakeLists.txt
===================================================================
--- llvm/lib/DebugInfo/Symbolize/CMakeLists.txt
+++ llvm/lib/DebugInfo/Symbolize/CMakeLists.txt
@@ -9,6 +9,7 @@
   LINK_COMPONENTS
   DebugInfoDWARF
   DebugInfoPDB
+  Debuginfod
   Object
   Support
   Demangle
Index: llvm/lib/DebugInfo/Symbolize/Symbolize.cpp
===================================================================
--- llvm/lib/DebugInfo/Symbolize/Symbolize.cpp
+++ 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 @@
       }
     }
   }
-  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
Index: llvm/test/lit.cfg.py
===================================================================
--- llvm/test/lit.cfg.py
+++ llvm/test/lit.cfg.py
@@ -394,6 +394,9 @@
 if config.have_libxml2:
     config.available_features.add('libxml2')
 
+if config.have_curl:
+    config.available_features.add('curl')
+
 if config.have_opt_viewer_modules:
     config.available_features.add('have_opt_viewer_modules')
 
Index: llvm/test/lit.site.cfg.py.in
===================================================================
--- llvm/test/lit.site.cfg.py.in
+++ llvm/test/lit.site.cfg.py.in
@@ -39,6 +39,7 @@
 config.have_zlib = @LLVM_ENABLE_ZLIB@
 config.have_libxar = @LLVM_HAVE_LIBXAR@
 config.have_libxml2 = @LLVM_ENABLE_LIBXML2@
+config.have_curl = @LLVM_ENABLE_CURL@
 config.have_dia_sdk = @LLVM_ENABLE_DIA_SDK@
 config.enable_ffi = @LLVM_ENABLE_FFI@
 config.build_examples = @LLVM_BUILD_EXAMPLES@
Index: llvm/test/tools/llvm-symbolizer/debuginfod.py
===================================================================
--- /dev/null
+++ llvm/test/tools/llvm-symbolizer/debuginfod.py
@@ -0,0 +1,58 @@
+# REQUIRES: curl
+## Uses source from split-debug.test
+# RUN: rm -rf %t && mkdir %t
+# RUN: llvm-objcopy --strip-debug %p/Inputs/addr.exe %t/addr.exe
+# RUN: mkdir -p %t/buildid/127da749021c1fc1a58cba734a1f542cbe2b7ce4/
+# RUN: llvm-objcopy --keep-section=.debug_info %p/Inputs/addr.exe \
+# RUN:   %t/buildid/127da749021c1fc1a58cba734a1f542cbe2b7ce4/debuginfo
+# RUN: python %S/debuginfod.py %t %t 'llvm-symbolizer --print-address \
+# RUN:   --obj=%t/addr.exe 0x40054d' | FileCheck %s
+
+# CHECK: 0x40054d
+# CHECK: {{[/\]+}}tmp{{[/\]+}}x.c:14:0
+
+
+import threading
+import http.server
+import functools
+import subprocess
+import os
+
+
+# Serves files at the serve_path, then runs the tool with specified args.
+# Sets the DEBUGINFOD_CACHE_PATH env var to point at given cache_directory.
+# Sets the DEBUGINFOD_URLS env var to point at the local server.
+def test_tool(serve_path, cache_directory, tool_args) -> int:
+    httpd = http.server.ThreadingHTTPServer(
+        ('',0), functools.partial(
+            http.server.SimpleHTTPRequestHandler,
+            directory=serve_path))
+    port = httpd.server_port
+    thread = threading.Thread(target=httpd.serve_forever)
+    try:
+        thread.start()
+        process = subprocess.Popen(
+            tool_args, env={**os.environ,
+            'DEBUGINFOD_URLS': f'http://localhost:{port}',
+            'DEBUGINFOD_CACHE_PATH': cache_directory})
+        if process.wait() != 0:
+            print('process returned nontrivial error code')
+            return 1
+    finally:
+        httpd.shutdown()
+        thread.join()
+    return 0
+
+def main():
+    import argparse
+    parser = argparse.ArgumentParser()
+    parser.add_argument('serve_path')
+    parser.add_argument('cache_directory')
+    parser.add_argument('tool_cmd')
+    args = parser.parse_args()
+    result = test_tool(args.serve_path, args.cache_directory,
+        args.tool_cmd.split())
+    os._exit(result)
+
+if __name__ == '__main__':
+    main()
Index: llvm/test/tools/llvm-symbolizer/lit.local.cfg
===================================================================
--- /dev/null
+++ llvm/test/tools/llvm-symbolizer/lit.local.cfg
@@ -0,0 +1 @@
+config.suffixes.add('.py')