Fix large overhead with itt notifications on region/barrier name composing

Currently, there is a big overhead in reporting of loop metadata through
ittnotify.  The pair of functions: __kmp_str_loc_init/__kmp_str_loc_free are
replaced with strchr/atoi calls.  Thus, a lot of time consuming actions are
skipped - many memory allocations/deallocations, heavy string duplication, etc.
The loop metadata only needs line and column info from the source string, so no
allocations and string splitting actually needed.

Patch by Andrey Churbanov

Differential Revision: http://reviews.llvm.org/D21309


git-svn-id: https://llvm.org/svn/llvm-project/openmp/trunk@272698 91177308-0d34-0410-b5e6-96231b3b80d8

runtime/src/kmp_itt.inl

@@ -348,17 +348,31 @@ __kmp_itt_metadata_loop( ident_t * loc, kmp_uint64 sched_type, kmp_uint64 iterat
     }
 
     __itt_string_handle * string_handle = __itt_string_handle_create( "omp_metadata_loop");
-    kmp_str_loc_t str_loc = __kmp_str_loc_init( loc->psource, 1 );
+
+    // Parse line and column from psource string: ";file;func;line;col;;"
+    char * s_line;
+    char * s_col;
+    KMP_DEBUG_ASSERT(loc->psource);
+#ifdef __cplusplus
+    s_line = strchr((char*)loc->psource, ';');
+#else
+    s_line = strchr(loc->psource, ';');
+#endif
+    KMP_DEBUG_ASSERT(s_line);
+    s_line = strchr(s_line + 1, ';');   // 2-nd semicolon
+    KMP_DEBUG_ASSERT(s_line);
+    s_line = strchr(s_line + 1, ';');   // 3-rd semicolon
+    KMP_DEBUG_ASSERT(s_line);
+    s_col = strchr(s_line + 1, ';');    // 4-th semicolon
+    KMP_DEBUG_ASSERT(s_col);
 
     kmp_uint64 loop_data[ 5 ];
-    loop_data[ 0 ] = str_loc.line;
-    loop_data[ 1 ] = str_loc.col;
+    loop_data[ 0 ] = atoi(s_line + 1); // read line
+    loop_data[ 1 ] = atoi(s_col + 1);  // read column
     loop_data[ 2 ] = sched_type;
     loop_data[ 3 ] = iterations;
     loop_data[ 4 ] = chunk;
 
-    __kmp_str_loc_free( &str_loc );
-
     __itt_metadata_add(metadata_domain, __itt_null, string_handle, __itt_metadata_u64, 5, loop_data);
 #endif
 } // __kmp_itt_metadata_loop