Public Counter Compiler fails awkwardly if public counter definition file has an uppercase character in it

[jcortell68]

The failure is easy to reproduce. Add an empty file

source\auto_generated\public_counter_compiler_input_files\public_counter_names_vk_gfxWhatever.txt

then run the Public Counter Compiler with API=VK and GPU Family=gfxWhatever. You'll end up with this error:

Compiling API VK for GPU Family gfxWhatever
Info: Unable to find file C:\j.cortell\git\gpu_performance_api\source\public_counter_compiler_input_files\public_counter_definitions_gfxwhatever_ter_names_vk_gfxwhatever.txt

That message is a bit long. Notice the simple filename that it says doesn't exist:

public_counter_definitions_gfxwhatever_ter_names_vk_gfxwhatever.txt

You can see it's malformed. The reason is that the logic in PublicCounterCompiler::CounterCompiler::CompileCounters() assumes that the files in source\public_counter_compiler_input_files have only lowercase characters in their names. That unchecked assumption, if false, results in a -1 value for asicIndex here. The code then proceeds to use the -1, resulting in the malformed filename in the error message.

At a minimum, it would be nice if the compiler failed with a comprehensible and actionable message if someone introduces a file with an uppercase character. The following addition produces a nice error message for me:

                 foreach (string counterNamesFile in baseGfxFileNames)
                 {
+                    string filename = Path.GetFileName(counterNamesFile);
+                    if (filename != filename.ToLower())
+                    {
+                        errorHandler("Public counter name file has uppercase characters in it: " + counterNamesFile);
+                        return false;
+                    }
+
                     fileNames.Add(counterNamesFile);
                 }

Of course, the alternative is to make the code work even if the file has an uppercase character in it. I'm not sure, though, if that would require adjustments in a bunch of places. I think it's perfectly fine to require the files to be all lowercase; the compiler just needs to tell the user when that requirement isn't met. I.e., the above would be a sufficient and safe fix in my book. The nonsensical message it is producing today isn't helpful and took some time to debug to discover what was really wrong.