1    :  // Copyright 2012 Google Inc. All Rights Reserved.
   2    :  //
   3    :  // Licensed under the Apache License, Version 2.0 (the "License");
   4    :  // you may not use this file except in compliance with the License.
   5    :  // You may obtain a copy of the License at
   6    :  //
   7    :  //     http://www.apache.org/licenses/LICENSE-2.0
   8    :  //
   9    :  // Unless required by applicable law or agreed to in writing, software
  10    :  // distributed under the License is distributed on an "AS IS" BASIS,
  11    :  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12    :  // See the License for the specific language governing permissions and
  13    :  // limitations under the License.
  14    :  //
  15    :  // The runtime portion of a basic-block entry counting agent. This is
  16    :  // responsible for initializing the RPC connection and per-thread entry-count
  17    :  // buffer on demand as necessary as well as saturation incrementing the
  18    :  // appropriate counter when requested.
  19    :  //
  20    :  // The instrumenter can be used to inject a run-time dependency on this
  21    :  // library as well as to add the appropriate entry-hook code.
  22    :  
  23    :  #ifndef SYZYGY_AGENT_BASIC_BLOCK_ENTRY_BASIC_BLOCK_ENTRY_H_
  24    :  #define SYZYGY_AGENT_BASIC_BLOCK_ENTRY_BASIC_BLOCK_ENTRY_H_
  25    :  
  26    :  #include <windows.h>
  27    :  #include <winnt.h>
  28    :  #include <vector>
  29    :  
  30    :  #include "base/lazy_instance.h"
  31    :  #include "base/win/pe_image.h"
  32    :  #include "syzygy/agent/common/thread_state.h"
  33    :  #include "syzygy/common/indexed_frequency_data.h"
  34    :  #include "syzygy/trace/client/rpc_session.h"
  35    :  
  36    :  // Instrumentation stub to handle entry to a basic-block.
  37  m :  extern "C" void _cdecl _basic_block_enter();
  38    :  
  39    :  // Instrumentation stub to handle the invocation of a DllMain-like entry point.
  40  m :  extern "C" void _cdecl _indirect_penter_dllmain();
  41    :  
  42    :  // Instrumentation stub to handle a request for a pointer to frequency data.
  43  m :  extern "C" uint32* _stdcall _get_raw_frequency_data(
  44  m :      ::common::IndexedFrequencyData* data);
  45    :  
  46  m :  namespace agent {
  47  m :  namespace basic_block_entry {
  48    :  
  49    :  // The basic-block entry counting agent.
  50    :  // @note: There's a single instance of this class.
  51  m :  class BasicBlockEntry {
  52  m :   public:
  53  m :    typedef ::common::IndexedFrequencyData IndexedFrequencyData;
  54  m :    typedef ::agent::common::ThreadStateManager ThreadStateManager;
  55    :  
  56    :    // This structure describes the contents of the stack above a call to
  57    :    // BasicBlockEntry::BasicBlockEntryHook. A pointer to this structure will
  58    :    // be given to the BasicBlockEntryHook by _basic_block_enter.
  59  m :    struct BasicBlockEntryFrame;
  60    :  
  61    :    // This structure describes the contents of the stack above a call to
  62    :    // BasicBlockEntry::DllMainEntryHook(). A pointer to this structure will
  63    :    // be given to the DllMainEntryHook by _indirect_penter_dllmain.
  64  m :    struct DllMainEntryFrame;
  65    :  
  66    :    // This structure describes the contents of the stack above a call to
  67    :    // BasicBlockEntry::ExeMainEntryHook(). A pointer to this structure will
  68    :    // be given to the ExeMainEntryHook by _indirect_penter_exemain.
  69  m :    struct ExeMainEntryFrame;
  70    :  
  71    :    // Retrieves the basic block entry singleton instance.
  72  m :    static BasicBlockEntry* Instance();
  73    :  
  74    :    // Returns a pointer to thread local frequency data. Used by the fast-path.
  75  m :    static uint32* WINAPI GetRawFrequencyData(IndexedFrequencyData* data);
  76    :  
  77    :    // Called from _basic_block_enter().
  78  m :    static void WINAPI BasicBlockEntryHook(BasicBlockEntryFrame* entry_frame);
  79    :  
  80    :    // Called from _indirect_penter_dllmain.
  81  m :    static void WINAPI DllMainEntryHook(DllMainEntryFrame* entry_frame);
  82    :  
  83    :    // Called from _indirect_penter_exemain.
  84  m :    static void WINAPI ExeMainEntryHook(ExeMainEntryFrame* entry_frame);
  85    :  
  86  m :   protected:
  87    :    // This class defines the per-thread-per-instrumented-module state managed
  88    :    // by this agent.
  89  m :    class ThreadState;
  90  m :    friend class ThreadState;
  91    :  
  92    :    // Make sure the LazyInstance can be created.
  93  m :    friend struct base::DefaultLazyInstanceTraits<BasicBlockEntry>;
  94    :  
  95  m :    BasicBlockEntry();
  96  m :    ~BasicBlockEntry();
  97    :  
  98    :    // Handles EXE startup on ExeMainEntryHook and DLL_PROCESS_ATTACH messages
  99    :    // received by DllMainEntryHook().
 100  m :    void OnProcessAttach(IndexedFrequencyData* module_data);
 101    :  
 102    :    // Handles DLL_THREAD_DETACH and DLL_PROCESS_DETACH messages received by
 103    :    // DllMainEntryHook().
 104  m :    void OnThreadDetach(IndexedFrequencyData* module_data);
 105    :  
 106    :    // Registers the module containing @p addr with the call_trace_service.
 107  m :    void RegisterModule(const void* addr);
 108    :  
 109    :    // Create the local thread state for the current thread. This should only
 110    :    // be called if the local thread state has not already been created.
 111  m :    ThreadState* CreateThreadState(IndexedFrequencyData* module_data);
 112    :  
 113    :    // The RPC session we're logging to/through.
 114  m :    trace::client::RpcSession session_;
 115    :  
 116    :    // A helper to manage the life-cycle of the ThreadState instances allocated
 117    :    // by this agent.
 118  m :    ThreadStateManager thread_state_manager_;
 119  m :  };
 120    :  
 121  m :  }  // namespace basic_block_entry
 122  m :  }  // namespace agent
 123    :  
 124    :  #endif  // SYZYGY_AGENT_BASIC_BLOCK_ENTRY_BASIC_BLOCK_ENTRY_H_