Misc module/dwarf logging improvements

This change improves the logging for the lldb.module category to note a few interesting cases:

1. Local object file found, but specs not matching
2. Local object file not found, using a placeholder module

The handling and logging for the cases wehre we fail to load compressed dwarf
symbols is also improved.

Differential Revision: https://reviews.llvm.org/D50274

llvm-svn: 339161

lldb/lit/Modules/compressed-sections.yaml

@@ -28,5 +28,4 @@ Sections:
 # CHECK-NEXT: Type: regular
 # CHECK-NEXT: VM size: 0
 # CHECK-NEXT: File size: 8
-# CHECK-NEXT: Data:
+# CHECK-NEXT: Data: ()
-# CHECK-NEXT: DEADBEEF BAADF00D

lldb/source/Core/Module.cpp

@@ -162,9 +162,13 @@ Module::Module(const ModuleSpec &module_spec)
   // fill any ivars in so we don't accidentally grab the wrong file later since
   // they don't match...
   ModuleSpec matching_module_spec;
-  if (modules_specs.FindMatchingModuleSpec(module_spec, matching_module_spec) ==
+  if (!modules_specs.FindMatchingModuleSpec(module_spec,
-      0)
+                                            matching_module_spec)) {
+    if (log) {
+      log->Printf("Found local object file but the specs didn't match");
+    }
     return;
+  }
 
   if (module_spec.GetFileSpec())
     m_mod_time = FileSystem::GetModificationTime(module_spec.GetFileSpec());

lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp

@@ -3385,8 +3385,6 @@ size_t ObjectFileELF::ReadSectionData(Section *section,
   if (section->GetObjectFile() != this)
     return section->GetObjectFile()->ReadSectionData(section, section_data);
 
-  Log *log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_MODULES);
-
   size_t result = ObjectFile::ReadSectionData(section, section_data);
   if (result == 0 || !section->Test(SHF_COMPRESSED))
     return result;
@@ -3397,20 +3395,27 @@ size_t ObjectFileELF::ReadSectionData(Section *section,
        size_t(section_data.GetByteSize())},
       GetByteOrder() == eByteOrderLittle, GetAddressByteSize() == 8);
   if (!Decompressor) {
-    LLDB_LOG_ERROR(log, Decompressor.takeError(),
+    GetModule()->ReportWarning(
-                   "Unable to initialize decompressor for section {0}",
+        "Unable to initialize decompressor for section '%s': %s",
-                   section->GetName());
+        section->GetName().GetCString(),
-    return result;
+        llvm::toString(Decompressor.takeError()).c_str());
+    section_data.Clear();
+    return 0;
   }
+
   auto buffer_sp =
       std::make_shared<DataBufferHeap>(Decompressor->getDecompressedSize(), 0);
-  if (auto Error = Decompressor->decompress(
+  if (auto error = Decompressor->decompress(
           {reinterpret_cast<char *>(buffer_sp->GetBytes()),
            size_t(buffer_sp->GetByteSize())})) {
-    LLDB_LOG_ERROR(log, std::move(Error), "Decompression of section {0} failed",
+    GetModule()->ReportWarning(
-                   section->GetName());
+        "Decompression of section '%s' failed: %s",
-    return result;
+        section->GetName().GetCString(),
+        llvm::toString(std::move(error)).c_str());
+    section_data.Clear();
+    return 0;
   }
+
   section_data.SetData(buffer_sp);
   return buffer_sp->GetByteSize();
 }

lldb/source/Plugins/Process/minidump/ProcessMinidump.cpp

@@ -365,6 +365,12 @@ void ProcessMinidump::ReadModuleList() {
       // This enables most LLDB functionality involving address-to-module
       // translations (ex. identifing the module for a stack frame PC) and
       // modules/sections commands (ex. target modules list, ...)
+      if (log) {
+        log->Printf("Unable to locate the matching object file, creating a "
+                    "placeholder module for: %s",
+                    name.getValue().c_str());
+      }
+
       auto placeholder_module =
           std::make_shared<PlaceholderModule>(module_spec);
       placeholder_module->CreateImageSection(module, GetTarget());

lldb/source/Target/Process.cpp

@@ -5842,7 +5842,7 @@ void Process::ModulesDidLoad(ModuleList &module_list) {
   // that loaded.
 
   // Iterate over a copy of this language runtime list in case the language
-  // runtime ModulesDidLoad somehow causes the language riuntime to be
+  // runtime ModulesDidLoad somehow causes the language runtime to be
   // unloaded.
   LanguageRuntimeCollection language_runtimes(m_language_runtimes);
   for (const auto &pair : language_runtimes) {