some performance optimisations (#135)

* allow a try_region_[begin|end] for performance improfments

Author: AndreasGocht

src/scorepy/cInstrumenter.cpp

@@ -115,31 +115,39 @@ bool CInstrumenter::on_event(PyFrameObject& frame, int what, PyObject*)
     case PyTrace_CALL:
     {
         const PyCodeObject& code = *frame.f_code;
-        const char* name = PyUnicode_AsUTF8(code.co_name);
-        const char* module_name = get_module_name(frame);
-        assert(name);
-        assert(module_name);
-        // TODO: Use string_view/CString comparison?
-        if (std::string(name) != "_unsetprofile" && std::string(module_name, 0, 6) != "scorep")
+        bool success = try_region_begin(reinterpret_cast<std::uintptr_t>(&code));
+        if (!success)
         {
-            const int line_number = code.co_firstlineno;
-            const auto file_name = get_file_name(frame);
-            region_begin(name, module_name, file_name, line_number,
-                         reinterpret_cast<std::uintptr_t>(&code));
+            const char* name = PyUnicode_AsUTF8(code.co_name);
+            const char* module_name = get_module_name(frame);
+            assert(name);
+            assert(module_name);
+            // TODO: Use string_view/CString comparison?
+            if (std::string(name) != "_unsetprofile" && std::string(module_name, 0, 6) != "scorep")
+            {
+                const int line_number = code.co_firstlineno;
+                const std::string file_name = get_file_name(frame);
+                region_begin(name, module_name, file_name, line_number,
+                             reinterpret_cast<std::uintptr_t>(&code));
+            }
         }
         break;
     }
     case PyTrace_RETURN:
     {
         const PyCodeObject& code = *frame.f_code;
-        const char* name = PyUnicode_AsUTF8(code.co_name);
-        const char* module_name = get_module_name(frame);
-        assert(name);
-        assert(module_name);
-        // TODO: Use string_view/CString comparison?
-        if (std::string(name) != "_unsetprofile" && std::string(module_name, 0, 6) != "scorep")
+        bool success = try_region_end(reinterpret_cast<std::uintptr_t>(&code));
+        if (!success)
         {
-            region_end(name, module_name, reinterpret_cast<std::uintptr_t>(&code));
+            const char* name = PyUnicode_AsUTF8(code.co_name);
+            const char* module_name = get_module_name(frame);
+            assert(name);
+            assert(module_name);
+            // TODO: Use string_view/CString comparison?
+            if (std::string(name) != "_unsetprofile" && std::string(module_name, 0, 6) != "scorep")
+            {
+                region_end(name, module_name, reinterpret_cast<std::uintptr_t>(&code));
+            }
         }
         break;
     }

src/scorepy/events.cpp

@@ -1,29 +1,16 @@
-#include "events.hpp"
-#include <Python.h>
 #include <algorithm>
 #include <array>
 #include <iostream>
-#include <scorep/SCOREP_User_Functions.h>
-#include <scorep/SCOREP_User_Variables.h>
-#include <unordered_map>
 
-namespace scorepy
-{
+#include <Python.h>
 
-struct region_handle
-{
-    constexpr region_handle() = default;
-    ~region_handle() = default;
-    constexpr bool operator==(const region_handle& other)
-    {
-        return this->value == other.value;
-    }
-    SCOREP_User_RegionHandle value = SCOREP_USER_INVALID_REGION;
-};
+#include "events.hpp"
+#include "pythonHelpers.hpp"
 
-constexpr region_handle uninitialised_region_handle = region_handle();
+namespace scorepy
+{
 
-static std::unordered_map<std::uintptr_t, region_handle> regions;
+std::unordered_map<std::uintptr_t, region_handle> regions;
 static std::unordered_map<std::string, region_handle> user_regions;
 static std::unordered_map<std::string, region_handle> rewind_regions;
 

src/scorepy/events.hpp

@@ -1,10 +1,32 @@
 #pragma once
-
 #include <cstdint>
 #include <string>
+#include <unordered_map>
+
+#include <scorep/SCOREP_User_Functions.h>
+#include <scorep/SCOREP_User_Variables.h>
 
 namespace scorepy
 {
+
+struct region_handle
+{
+    constexpr region_handle() = default;
+    ~region_handle() = default;
+    constexpr bool operator==(const region_handle& other)
+    {
+        return this->value == other.value;
+    }
+    constexpr bool operator!=(const region_handle& other)
+    {
+        return this->value != other.value;
+    }
+
+    SCOREP_User_RegionHandle value = SCOREP_USER_INVALID_REGION;
+};
+
+constexpr region_handle uninitialised_region_handle = region_handle();
+
 /// Combine the arguments into a region name
 /// Return value is a statically allocated string to avoid memory (re)allocations
 inline const std::string& make_region_name(const std::string& module_name, const std::string& name)
@@ -16,12 +38,48 @@ inline const std::string& make_region_name(const std::string& module_name, const
     return region;
 }
 
+extern std::unordered_map<std::uintptr_t, region_handle> regions;
+
+/** tries to enter a region. Return true on success
+ *
+ */
+inline bool try_region_begin(std::uintptr_t identifier)
+{
+    auto it = regions.find(identifier);
+    if (it != regions.end())
+    {
+        SCOREP_User_RegionEnter(it->second.value);
+        return true;
+    }
+    else
+    {
+        return false;
+    }
+}
+
 void region_begin(const std::string& function_name, const std::string& module,
                   const std::string& file_name, const std::uint64_t line_number,
                   const std::uintptr_t& identifier);
 void region_begin(const std::string& function_name, const std::string& module,
                   const std::string& file_name, const std::uint64_t line_number);
 
+/** tries to end a region. Return true on success
+ *
+ */
+inline bool try_region_end(std::uintptr_t identifier)
+{
+    auto it_region = regions.find(identifier);
+    if (it_region != regions.end())
+    {
+        SCOREP_User_RegionEnd(it_region->second.value);
+        return true;
+    }
+    else
+    {
+        return false;
+    }
+}
+
 void region_end(const std::string& function_name, const std::string& module,
                 const std::uintptr_t& identifier);
 void region_end(const std::string& function_name, const std::string& module);
@@ -34,5 +92,4 @@ void rewind_end(std::string region_name, bool value);
 void parameter_int(std::string name, int64_t value);
 void parameter_uint(std::string name, uint64_t value);
 void parameter_string(std::string name, std::string value);
-
 } // namespace scorepy