Add a benchmark that validates how much time LLDB spends trying to fully print a fairly large std::list<T>

This is meant to help me track optimizations to the libc++ std::list data formatter

llvm-svn: 254755

lldb/packages/Python/lldbsuite/test/benchmarks/libcxxlist/Makefile

@@ -0,0 +1,5 @@
+LEVEL = ../../make
+
+CXX_SOURCES := main.cpp
+
+include $(LEVEL)/Makefile.rules

lldb/packages/Python/lldbsuite/test/benchmarks/libcxxlist/TestBenchmarkLibcxxList.py

@@ -0,0 +1,59 @@
+"""
+Test lldb data formatter subsystem.
+"""
+
+from __future__ import print_function
+
+
+
+import os, time
+import lldb
+from lldbsuite.test.lldbbench import *
+import lldbsuite.test.lldbutil as lldbutil
+
+class TestBenchmarkLibcxxList(BenchBase):
+
+    mydir = TestBase.compute_mydir(__file__)
+
+    @benchmarks_test
+    def test_run_command(self):
+        """Benchmark the std::list data formatter (libc++)"""
+        self.build()
+        self.data_formatter_commands()
+
+    def setUp(self):
+        # Call super's setUp().
+        BenchBase.setUp(self)
+
+    def data_formatter_commands(self):
+        """Benchmark the std::list data formatter (libc++)"""
+        self.runCmd("file a.out", CURRENT_EXECUTABLE_SET)
+
+        bkpt = self.target().FindBreakpointByID(lldbutil.run_break_set_by_source_regexp (self, "break here"))
+
+        self.runCmd("run", RUN_SUCCEEDED)
+
+        # The stop reason of the thread should be breakpoint.
+        self.expect("thread list", STOPPED_DUE_TO_BREAKPOINT,
+            substrs = ['stopped',
+                       'stop reason = breakpoint'])
+
+        # This is the function to remove the custom formats in order to have a
+        # clean slate for the next test case.
+        def cleanup():
+            self.runCmd('type format clear', check=False)
+            self.runCmd('type summary clear', check=False)
+            self.runCmd('type filter clear', check=False)
+            self.runCmd('type synth clear', check=False)
+            self.runCmd("settings set target.max-children-count 256", check=False)
+
+        # Execute the cleanup function during test case tear down.
+        self.addTearDownHook(cleanup)
+        
+        sw = Stopwatch()
+        
+        sw.start()
+        self.expect('frame variable -A list', substrs=['[300]', '300'])
+        sw.stop()
+            
+        print("time to print: %s" % (sw))

lldb/packages/Python/lldbsuite/test/benchmarks/libcxxlist/main.cpp

@@ -0,0 +1,11 @@
+#include <list>
+
+int main()
+{
+    std::list<int> list;
+    for (int i = 0;
+    i < 1500;
+    i++)
+        list.push_back(i);
+    return list.size(); // break here
+}