Add query canonicalization profiling

A small helper program like this helps figure out performance problems
with the function.

server/core/test/CMakeLists.txt

@@ -1,4 +1,5 @@
 add_executable(profile_trxboundaryparser profile_trxboundaryparser.cc)
+add_executable(profile_get_canonical profile_get_canonical.cc)
 add_executable(test_adminusers test_adminusers.cc)
 add_executable(test_atomic test_atomic.cc)
 add_executable(test_buffer test_buffer.cc)
@@ -26,6 +27,7 @@ add_executable(test_utils test_utils.cc)
 add_executable(test_session_track test_session_track.cc)
 
 target_link_libraries(profile_trxboundaryparser maxscale-common)
+target_link_libraries(profile_get_canonical maxscale-common)
 target_link_libraries(test_adminusers maxscale-common)
 target_link_libraries(test_atomic maxscale-common)
 target_link_libraries(test_buffer maxscale-common)

server/core/test/profile_get_canonical.cc

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2016 MariaDB Corporation Ab
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file and at www.mariadb.com/bsl11.
+ *
+ * Change Date: 2022-01-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2 or later of the General
+ * Public License.
+ */
+
+#include <maxscale/ccdefs.hh>
+#include <maxscale/modutil.hh>
+#include <iostream>
+#include <sstream>
+#include <chrono>
+
+using Clock = std::chrono::steady_clock;
+using std::chrono::duration_cast;
+using std::chrono::milliseconds;
+
+int main(int argc, char* argv[])
+{
+    int ITERATIONS = 10000000;
+
+    for (std::string line; std::getline(std::cin, line);)
+    {
+        GWBUF* buf = modutil_create_query(line.c_str());
+        auto start = Clock::now();
+
+        for (int i = 0; i < ITERATIONS; i++)
+        {
+            auto str = mxs::get_canonical(buf);
+        }
+
+        auto end = Clock::now();
+        gwbuf_free(buf);
+
+        std::cout << line << "\n"
+                  << duration_cast<milliseconds>(end - start).count() << "ms\n\n";
+    }
+
+    return 0;
+}