Implement GetLoadAddress for the Windows process plugin

Summary:
When a process is loaded, update its sections with the load address to resolve any created breakpoints. For the remote debugging case, the debugged process is launched remotely so GetLoadAddress is intended to pass the load address from remote to LLDB (client).


Reviewers: zturner, llvm-commits, clayborg, labath

Reviewed By: labath

Subscribers: mgorny, sas, Hui, clayborg, labath, lldb-commits

Differential Revision: https://reviews.llvm.org/D56237

llvm-svn: 354099

2 files changed, 92 insertions, 15 deletions

diff --git a/lldb/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.cpp b/lldb/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.cpp
index 727a4ae5cc4..f45d7116dcf 100644
--- a/lldb/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.cpp
+++ b/lldb/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.cpp
@@ -12,6 +12,7 @@
 #include "lldb/Core/Module.h"
 #include "lldb/Core/PluginManager.h"
 #include "lldb/Target/ExecutionContext.h"
+#include "lldb/Target/Platform.h"
 #include "lldb/Target/Process.h"
 #include "lldb/Target/RegisterContext.h"
 #include "lldb/Target/Target.h"
@@ -61,6 +62,56 @@ DynamicLoader *DynamicLoaderWindowsDYLD::CreateInstance(Process *process,
   return nullptr;
 }
 
+void DynamicLoaderWindowsDYLD::OnLoadModule(const ModuleSpec &module_spec,
+                                            lldb::addr_t module_addr) {
+  // Confusingly, there is no Target::AddSharedModule.  Instead, calling
+  // GetSharedModule() with a new module will add it to the module list and
+  // return a corresponding ModuleSP.
+  Status error;
+  ModuleSP module_sp =
+      m_process->GetTarget().GetSharedModule(module_spec, &error);
+  if (error.Fail())
+    return;
+
+  m_loaded_modules[module_sp] = module_addr;
+  UpdateLoadedSectionsCommon(module_sp, module_addr, false);
+}
+
+void DynamicLoaderWindowsDYLD::OnUnloadModule(lldb::addr_t module_addr) {
+  Address resolved_addr;
+  if (!m_process->GetTarget().ResolveLoadAddress(module_addr, resolved_addr))
+    return;
+
+  ModuleSP module_sp = resolved_addr.GetModule();
+  if (module_sp) {
+    m_loaded_modules.erase(module_sp);
+    UnloadSectionsCommon(module_sp);
+  }
+}
+
+lldb::addr_t DynamicLoaderWindowsDYLD::GetLoadAddress(ModuleSP executable) {
+  // First, see if the load address is already cached.
+  auto it = m_loaded_modules.find(executable);
+  if (it != m_loaded_modules.end() && it->second != LLDB_INVALID_ADDRESS)
+    return it->second;
+
+  lldb::addr_t load_addr = LLDB_INVALID_ADDRESS;
+
+  // Second, try to get it through the process plugins.  For a remote process,
+  // the remote platform will be responsible for providing it.
+  FileSpec file_spec(executable->GetPlatformFileSpec());
+  bool is_loaded = false;
+  Status status =
+      m_process->GetFileLoadAddress(file_spec, is_loaded, load_addr);
+  // Servers other than lldb server could respond with a bogus address.
+  if (status.Success() && is_loaded && load_addr != LLDB_INVALID_ADDRESS) {
+    m_loaded_modules[executable] = load_addr;
+    return load_addr;
+  }
+
+  return LLDB_INVALID_ADDRESS;
+}
+
 void DynamicLoaderWindowsDYLD::DidAttach() {
     Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
   if (log)
@@ -73,21 +124,17 @@ void DynamicLoaderWindowsDYLD::DidAttach() {
 
   // Try to fetch the load address of the file from the process, since there
   // could be randomization of the load address.
+  lldb::addr_t load_addr = GetLoadAddress(executable);
+  if (load_addr == LLDB_INVALID_ADDRESS)
+    return;
 
-  // It might happen that the remote has a different dir for the file, so we
-  // only send the basename of the executable in the query. I think this is safe
-  // because I doubt that two executables with the same basenames are loaded in
-  // memory...
-  FileSpec file_spec(
-      executable->GetPlatformFileSpec().GetFilename().GetCString());
-  bool is_loaded;
-  addr_t base_addr = 0;
-  lldb::addr_t load_addr;
-  Status error = m_process->GetFileLoadAddress(file_spec, is_loaded, load_addr);
-  if (error.Success() && is_loaded) {
-    base_addr = load_addr;
-    UpdateLoadedSections(executable, LLDB_INVALID_ADDRESS, base_addr, false);
-  }
+  // Request the process base address.
+  lldb::addr_t image_base = m_process->GetImageInfoAddress();
+  if (image_base == load_addr)
+    return;
+
+  // Rebase the process's modules if there is a mismatch.
+  UpdateLoadedSections(executable, LLDB_INVALID_ADDRESS, load_addr, false);
 
   ModuleList module_list;
   module_list.Append(executable);
@@ -95,7 +142,26 @@ void DynamicLoaderWindowsDYLD::DidAttach() {
   m_process->LoadModules();
 }
 
-void DynamicLoaderWindowsDYLD::DidLaunch() {}
+void DynamicLoaderWindowsDYLD::DidLaunch() {
+  Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
+  if (log)
+    log->Printf("DynamicLoaderWindowsDYLD::%s()", __FUNCTION__);
+
+  ModuleSP executable = GetTargetExecutable();
+  if (!executable.get())
+    return;
+
+  lldb::addr_t load_addr = GetLoadAddress(executable);
+  if (load_addr != LLDB_INVALID_ADDRESS) {
+    // Update the loaded sections so that the breakpoints can be resolved.
+    UpdateLoadedSections(executable, LLDB_INVALID_ADDRESS, load_addr, false);
+
+    ModuleList module_list;
+    module_list.Append(executable);
+    m_process->GetTarget().ModulesDidLoad(module_list);
+    m_process->LoadModules();
+  }
+}
 
 Status DynamicLoaderWindowsDYLD::CanLoadImage() { return Status(); }
 
diff --git a/lldb/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.h b/lldb/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.h
index 5eb39008573..ef859255db1 100644
--- a/lldb/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.h
+++ b/lldb/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.h
@@ -12,6 +12,8 @@
 #include "lldb/Target/DynamicLoader.h"
 #include "lldb/lldb-forward.h"
 
+#include <map>
+
 namespace lldb_private {
 
 class DynamicLoaderWindowsDYLD : public DynamicLoader {
@@ -27,6 +29,9 @@ public:
 
   static DynamicLoader *CreateInstance(Process *process, bool force);
 
+  void OnLoadModule(const ModuleSpec &module_spec, lldb::addr_t module_addr);
+  void OnUnloadModule(lldb::addr_t module_addr);
+
   void DidAttach() override;
   void DidLaunch() override;
   Status CanLoadImage() override;
@@ -35,6 +40,12 @@ public:
 
   ConstString GetPluginName() override;
   uint32_t GetPluginVersion() override;
+
+protected:
+  lldb::addr_t GetLoadAddress(lldb::ModuleSP executable);
+
+private:
+  std::map<lldb::ModuleSP, lldb::addr_t> m_loaded_modules;
 };
 
 } // namespace lldb_private