Fail gracefully if no inlining model is available to download.

[mtrofin]

llvm/lib/Analysis/CMakeLists.txt

17 ↗

(On Diff #354127)

should this be handled in TensorflowCompile.cmake? Likely common behavior.

[jacobhegna]

Move the relevant code to TensorflowCompile.cmake.

When removing a model, the default url should be set to the string literal
"none".

We cannot simply set it to "", as cmake will then think that the call to
tf_find_and_compile is missing and argument.

[jacobhegna]

Change "none" -> "TO_BE_UPDATED".

llvm/cmake/modules/TensorFlowCompile.cmake

function(tfcompile model tag_set signature_def_key fname cpp_class)
   set(GENERATED_HEADERS ${GENERATED_HEADERS} ${hdr_file} PARENT_SCOPE)
   set_source_files_properties(${hdr_file} PROPERTIES
     GENERATED 1)
 
 endfunction()
 
 function(tf_find_and_compile model default_url default_path generation_config tag_set signature_def_key fname cpp_class)
   if ("${model}" STREQUAL "download")
+    # Crash if the user wants to download a model but a URL is set to "TO_BE_UPDATED"
+    if ("${LLVM_INLINER_MODEL_CURRENT_URL}" STREQUAL "TO_BE_UPDATED")
+        message(FATAL_ERROR "LLVM_INLINER_MODEL_PATH was set to 'download' but there is no model url currently specified in cmake - likely, the model interface recently changed, and so there is not a released model available.")
+    endif()
+
     set(model ${default_url})
   endif()
 
   if ("${model}" STREQUAL "autogenerate")
     generate_mock_model(${default_path} models/generate_mock_model.py ${generation_config})
     set(model ${default_path}-autogenerated)
   endif()