[SYCL][UR] Log sycl-ls adapter errors in verbose mode

[bratpiorka]

Log sycl-ls adapter errors in verbose mode. Additionally, inform the user about verbose mode when no platforms are found.

[npmiller]

Looks great! Although I think we should also still downgrade the message from error to info, since there's plenty of cases where it's not an error

[RossBrunton]

nullptr is preferred over NULL in C++.

[RossBrunton]

Should this not be orig_ur_log_loader_var_str = std::getenv("UR_LOG_LOADER")?

[rafbiels]

orig_ur_log_loader_var = std::getenv("UR_LOG_LOADER") (the char* not the string)

[RossBrunton]

Why are we setting this unconditionally? Someone might want to run UR_LOG_LOADER="level:error;output:file,some_file" sycl-ls --verbose in order to capture the output into a file rather than stderr.

[bratpiorka]

okay, I see - what do you suggest in this case?

[rafbiels]

We could parse the variable if it's already set by the user, and:

1. set level to error if not already set to a lower level (e.g. user sets level:info)
2. set output to stderr if not set already and level is error (I wouldn't redirect info and debug to stderr)

Otherwise, if the variable is unset, then set "level:error;output:stderr".

Pseudocode:

if var_is_set:

  if not level_is_set:
    level = error

  if level >= error and not output_is_set:
    output = stderr

else:
  level = error
  output = stderr

[RossBrunton]

I think if it is set at all then we should just ignore it; presumably the user knows what they are doing. But Rafbeils' solution is fine by me as well.

[bratpiorka]

@rafbiels , I think parsing the log variable might be overly complicated. I agree with @RossBrunton that if the user is already aware of the UR_LOG_LOADER env var and knows how to set it, no further help is needed.
I have updated my PR so that if the UR_LOG_LOADER evn var is set, we do not modify it.

[rafbiels]

makes sense, I'm also happy with that 👍

[HPS-1]

LGTM!

[bratpiorka]

@intel/llvm-gatekeepers please merge

[bratpiorka]

@llvm-reviewers-runtime please review

[bratpiorka]

rebased,
@intel/llvm-gatekeepers please merge

[aelovikov-intel]

rebased, @intel/llvm-gatekeepers please merge

CI isn't ready yet. Please ping us once it is.

[bratpiorka]

I see some errors not related to my changes - are the machines working correctly?

default_selector() : No device of requested type available.
accelerator_selector() : No device of requested type available.
cpu_selector() : No device of requested type available.
gpu_selector() : No device of requested type available.
custom_selector(gpu) : No device of requested type available.
custom_selector(cpu) : No device of requested type available.
custom_selector(acc) : No device of requested type available.

Error: The action has timed out.

@intel/llvm-gatekeepers please merge

[sarnex]

im investigating