Fetch object file load address if it isn't specified by the linker

Differential revision: http://reviews.llvm.org/D10490

llvm-svn: 240052

12 files changed, 176 insertions, 2 deletions

diff --git a/lldb/docs/lldb-gdb-remote.txt b/lldb/docs/lldb-gdb-remote.txt
index 2b89c3451f0..b471b245f85 100644
--- a/lldb/docs/lldb-gdb-remote.txt
+++ b/lldb/docs/lldb-gdb-remote.txt
@@ -988,6 +988,24 @@ for this region.
 //----------------------------------------------------------------------
 
 //----------------------------------------------------------------------
+// qFileLoadAddress:<file_path>
+//
+// BRIEF
+//  Get the load address of a memory mapped file.
+//  The load address is defined as the address of the first memory
+//  region what contains data mapped from the specified file.
+//
+// RESPONSE
+//  <unsinged-hex64> - Load address of the file in big endian encoding
+//  "E01" - the requested file isn't loaded
+//  "EXX" - for any other errors
+//
+// PRIORITY TO IMPLEMENT
+//  Low, required if dynamic linker don't fill in the load address of
+//  some object file in the rendezvous data structure.
+//----------------------------------------------------------------------
+
+//----------------------------------------------------------------------
 // qModuleInfo:<module_path>;<arch triple>
 //
 // BRIEF
diff --git a/lldb/include/lldb/Host/common/NativeProcessProtocol.h b/lldb/include/lldb/Host/common/NativeProcessProtocol.h
index a1ddaec7f8a..f6a685aae14 100644
--- a/lldb/include/lldb/Host/common/NativeProcessProtocol.h
+++ b/lldb/include/lldb/Host/common/NativeProcessProtocol.h
@@ -16,6 +16,7 @@
 #include "lldb/lldb-types.h"
 #include "lldb/Core/Error.h"
 #include "lldb/Host/Mutex.h"
+#include "llvm/ADT/StringRef.h"
 
 #include "NativeBreakpointList.h"
 #include "NativeWatchpointList.h"
@@ -293,6 +294,9 @@ namespace lldb_private
         virtual Error
         GetLoadedModuleFileSpec(const char* module_path, FileSpec& file_spec) = 0;
 
+        virtual Error
+        GetFileLoadAddress(const llvm::StringRef& file_name, lldb::addr_t& load_addr) = 0;
+
     protected:
         lldb::pid_t m_pid;
 
diff --git a/lldb/include/lldb/Target/Process.h b/lldb/include/lldb/Target/Process.h
index 17bc88897a8..0e0838d4bc3 100644
--- a/lldb/include/lldb/Target/Process.h
+++ b/lldb/include/lldb/Target/Process.h
@@ -3036,6 +3036,28 @@ public:
     virtual bool
     GetModuleSpec(const FileSpec& module_file_spec, const ArchSpec& arch, ModuleSpec &module_spec);
 
+    //------------------------------------------------------------------
+    /// Try to find the load address of a file.
+    /// The load address is defined as the address of the first memory
+    /// region what contains data mapped from the specified file.
+    ///
+    /// @param[in] file 
+    ///     The name of the file whose load address we are looking for
+    ///
+    /// @param[out] is_loaded
+    ///     \b True if the file is loaded into the memory and false
+    ///     otherwise.
+    ///
+    /// @param[out] load_addr
+    ///     The load address of the file if it is loaded into the
+    ///     processes address space, LLDB_INVALID_ADDRESS otherwise.
+    //------------------------------------------------------------------
+    virtual Error
+    GetFileLoadAddress(const FileSpec& file, bool& is_loaded, lldb::addr_t& load_addr)
+    {
+        return Error("Not supported");
+    }
+
 protected:
 
     //------------------------------------------------------------------
diff --git a/lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DYLDRendezvous.cpp b/lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DYLDRendezvous.cpp
index 2d17fccd75a..b8cc286874c 100644
--- a/lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DYLDRendezvous.cpp
+++ b/lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DYLDRendezvous.cpp
@@ -412,6 +412,17 @@ DYLDRendezvous::ReadSOEntryFromMemory(lldb::addr_t addr, SOEntry &entry)
 
     entry.file_spec.SetFile(ReadStringFromMemory(entry.path_addr), false);
 
+    // The base_addr is not filled in for some case.
+    // Try to figure it out based on the load address of the object file.
+    if (entry.base_addr == 0)
+    {
+        lldb::addr_t load_addr = LLDB_INVALID_ADDRESS;
+        bool is_loaded = false;
+        Error error = m_process->GetFileLoadAddress(entry.file_spec, is_loaded, load_addr);
+        if (error.Success() && is_loaded)
+            entry.base_addr = load_addr;
+    }
+
     return true;
 }
 
diff --git a/lldb/source/Plugins/Process/Linux/NativeProcessLinux.cpp b/lldb/source/Plugins/Process/Linux/NativeProcessLinux.cpp
index be07b436580..be4b3193050 100644
--- a/lldb/source/Plugins/Process/Linux/NativeProcessLinux.cpp
+++ b/lldb/source/Plugins/Process/Linux/NativeProcessLinux.cpp
@@ -3649,6 +3649,39 @@ NativeProcessLinux::GetLoadedModuleFileSpec(const char* module_path, FileSpec& f
 }
 
 Error
+NativeProcessLinux::GetFileLoadAddress(const llvm::StringRef& file_name, lldb::addr_t& load_addr)
+{
+    load_addr = LLDB_INVALID_ADDRESS;
+    Error error = ProcFileReader::ProcessLineByLine (GetID (), "maps",
+        [&] (const std::string &line) -> bool
+        {
+            StringRef maps_row(line);
+ 
+            SmallVector<StringRef, 16> maps_columns;
+            maps_row.split(maps_columns, StringRef(" "), -1, false);
+ 
+            if (maps_columns.size() < 6)
+            {
+                // Return true to continue reading the proc file
+                return true;
+            }
+
+            if (maps_columns[5] == file_name)
+            {
+                StringExtractor addr_extractor(maps_columns[0].str().c_str());
+                load_addr = addr_extractor.GetHexMaxU64(false, LLDB_INVALID_ADDRESS); 
+
+                // Return false to stop reading the proc file further
+                return false;
+            }
+ 
+            // Return true to continue reading the proc file
+            return true;
+        });
+    return error; 
+}
+
+Error
 NativeProcessLinux::ResumeThread(
         lldb::tid_t tid,
         NativeThreadLinux::ResumeThreadFunction request_thread_resume_function,
diff --git a/lldb/source/Plugins/Process/Linux/NativeProcessLinux.h b/lldb/source/Plugins/Process/Linux/NativeProcessLinux.h
index 137f7fdf8a9..1964aea6a19 100644
--- a/lldb/source/Plugins/Process/Linux/NativeProcessLinux.h
+++ b/lldb/source/Plugins/Process/Linux/NativeProcessLinux.h
@@ -152,6 +152,9 @@ namespace process_linux {
         Error
         GetLoadedModuleFileSpec(const char* module_path, FileSpec& file_spec) override;
 
+        Error
+        GetFileLoadAddress(const llvm::StringRef& file_name, lldb::addr_t& load_addr) override;
+
         // ---------------------------------------------------------------------
         // Interface used by NativeRegisterContext-derived classes.
         // ---------------------------------------------------------------------
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp
index 8b31dbecec7..e8955ddbd6e 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp
@@ -53,6 +53,7 @@
 using namespace lldb;
 using namespace lldb_private;
 using namespace lldb_private::process_gdb_remote;
+using namespace llvm;
 
 //----------------------------------------------------------------------
 // GDBRemote Errors
@@ -134,6 +135,8 @@ GDBRemoteCommunicationServerLLGS::RegisterPacketHandlers()
                                   &GDBRemoteCommunicationServerLLGS::Handle_qC);
     RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_qfThreadInfo,
                                   &GDBRemoteCommunicationServerLLGS::Handle_qfThreadInfo);
+    RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_qFileLoadAddress,
+                                  &GDBRemoteCommunicationServerLLGS::Handle_qFileLoadAddress);
     RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_qGetWorkingDir,
                                   &GDBRemoteCommunicationServerLLGS::Handle_qGetWorkingDir);
     RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_qMemoryRegionInfo,
@@ -2600,6 +2603,34 @@ GDBRemoteCommunicationServerLLGS::Handle_qWatchpointSupportInfo (StringExtractor
     return SendPacketNoLock(response.GetData(), response.GetSize());
 }
 
+GDBRemoteCommunication::PacketResult
+GDBRemoteCommunicationServerLLGS::Handle_qFileLoadAddress (StringExtractorGDBRemote &packet)
+{
+    // Fail if we don't have a current process.
+    if (!m_debugged_process_sp ||
+            m_debugged_process_sp->GetID () == LLDB_INVALID_PROCESS_ID)
+        return SendErrorResponse(67);
+
+    packet.SetFilePos(strlen("qFileLoadAddress:"));
+    if (packet.GetBytesLeft() == 0)
+        return SendErrorResponse(68);
+
+    std::string file_name;
+    packet.GetHexByteString(file_name);
+
+    lldb::addr_t file_load_address = LLDB_INVALID_ADDRESS;
+    Error error = m_debugged_process_sp->GetFileLoadAddress(file_name, file_load_address);
+    if (error.Fail())
+        return SendErrorResponse(69);
+
+    if (file_load_address == LLDB_INVALID_ADDRESS)
+        return SendErrorResponse(1); // File not loaded
+
+    StreamGDBRemote response;
+    response.PutHex64(file_load_address);
+    return SendPacketNoLock(response.GetData(), response.GetSize());
+}
+
 void
 GDBRemoteCommunicationServerLLGS::FlushInferiorOutput ()
 {
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.h b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.h
index a5e2bbcc2be..1eda0b052bb 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.h
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.h
@@ -236,6 +236,9 @@ protected:
     PacketResult
     Handle_qWatchpointSupportInfo (StringExtractorGDBRemote &packet);
 
+    PacketResult
+    Handle_qFileLoadAddress (StringExtractorGDBRemote &packet);
+
     void
     SetCurrentThreadID (lldb::tid_t tid);
 
diff --git a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
index 355f052b786..64972dfda36 100644
--- a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
@@ -4121,6 +4121,47 @@ ProcessGDBRemote::LoadModules ()
     return new_modules.GetSize();
 }
 
+Error
+ProcessGDBRemote::GetFileLoadAddress(const FileSpec& file, bool& is_loaded, lldb::addr_t& load_addr)
+{
+    is_loaded = false;
+    load_addr = LLDB_INVALID_ADDRESS;
+
+    std::string file_path = file.GetPath(false);
+    if (file_path.empty ())
+        return Error("Empty file name specified");
+
+    StreamString packet;
+    packet.PutCString("qFileLoadAddress:");
+    packet.PutCStringAsRawHex8(file_path.c_str());
+
+    StringExtractorGDBRemote response;
+    if (m_gdb_comm.SendPacketAndWaitForResponse(packet.GetString().c_str(), response, false) != GDBRemoteCommunication::PacketResult::Success)
+        return Error("Sending qFileLoadAddress packet failed");
+
+    if (response.IsErrorResponse())
+    {
+        if (response.GetError() == 1)
+        {
+            // The file is not loaded into the inferior
+            is_loaded = false;
+            load_addr = LLDB_INVALID_ADDRESS;
+            return Error();
+        }
+
+        return Error("Fetching file load address from remote server returned an error");
+    }
+
+    if (response.IsNormalResponse())
+    {
+        is_loaded = true;
+        load_addr = response.GetHexMaxU64(false, LLDB_INVALID_ADDRESS);
+        return Error();
+    }
+
+    return Error("Unknown error happened during sending the load address packet");
+}
+
 class CommandObjectProcessGDBRemoteSpeedTest: public CommandObjectParsed
 {
 public:
diff --git a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
index 21e633301d0..02f449ffca4 100644
--- a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
+++ b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
@@ -238,8 +238,11 @@ public:
                   const ArchSpec& arch,
                   ModuleSpec &module_spec) override;
 
-    virtual size_t
-    LoadModules () override;
+    size_t
+    LoadModules() override;
+
+    Error
+    GetFileLoadAddress(const FileSpec& file, bool& is_loaded, lldb::addr_t& load_addr) override;
 
 protected:
     friend class ThreadGDBRemote;
diff --git a/lldb/source/Utility/StringExtractorGDBRemote.cpp b/lldb/source/Utility/StringExtractorGDBRemote.cpp
index 718c8f6e996..aeceaa00fa1 100644
--- a/lldb/source/Utility/StringExtractorGDBRemote.cpp
+++ b/lldb/source/Utility/StringExtractorGDBRemote.cpp
@@ -144,6 +144,10 @@ StringExtractorGDBRemote::GetServerPacketType () const
             if (PACKET_STARTS_WITH ("qEcho:"))                  return eServerPacketType_qEcho;
             break;
 
+        case 'F':
+            if (PACKET_STARTS_WITH ("qFileLoadAddress:"))       return eServerPacketType_qFileLoadAddress;
+            break;
+
         case 'G':
             if (PACKET_STARTS_WITH ("qGroupName:"))             return eServerPacketType_qGroupName;
             if (PACKET_MATCHES ("qGetWorkingDir"))              return eServerPacketType_qGetWorkingDir;
diff --git a/lldb/source/Utility/StringExtractorGDBRemote.h b/lldb/source/Utility/StringExtractorGDBRemote.h
index 78f60217d86..beb07e5b57e 100644
--- a/lldb/source/Utility/StringExtractorGDBRemote.h
+++ b/lldb/source/Utility/StringExtractorGDBRemote.h
@@ -61,6 +61,7 @@ public:
         eServerPacketType_qSpeedTest,
         eServerPacketType_qUserName,
         eServerPacketType_qGetWorkingDir,
+        eServerPacketType_qFileLoadAddress,
         eServerPacketType_QEnvironment,
         eServerPacketType_QLaunchArch,
         eServerPacketType_QSetDisableASLR,