OptionOverride parser does not support the same syntax as XLA_FLAGS for enum values [jax.jit(..., compiler_options={...})]

[olupton]

This means that, for example, setting

--xla_gpu_enable_command_buffer=+conditional

with XLA_FLAGS works, but passing it via

jax.jit(..., compiler_options={"xla_gpu_enable_command_buffer": "+conditional"})

does not work. It seems there are multiple reasons:

First, the + syntax is not understood.
Second, parsing from enum string names is case-sensitive in the second path.
Third, parsing from enum string names appears to be buggy as this branch does not return success:

xla/xla/pjrt/pjrt_executable.cc

Lines 681 to 687 in 5131caa

	if (enum_desc != nullptr) {
	if (field->is_repeated()) {
	reflection->AddEnum(&debug_options, field, enum_desc);
	} else {
	reflection->SetEnum(&debug_options, field, enum_desc);
	}
	}

(also, integer enum values are not validated)

It also does not seem to be possible to set multiple values via compiler_options, whereas XLA_FLAGS supports this using a comma-separated format.

These two paths should support the same syntax.