[llvm] f34ef24 - [mlgo] Skip AOT-compiling a model if a header/object pair is provided

[Mircea Trofin via llvm-commits]

Author: Mircea Trofin
Date: 2021-04-13T09:46:29-07:00
New Revision: f34ef248d37456b9978d88eee4b349076e2798a1

URL: https://github.com/llvm/llvm-project/commit/f34ef248d37456b9978d88eee4b349076e2798a1
DIFF: https://github.com/llvm/llvm-project/commit/f34ef248d37456b9978d88eee4b349076e2798a1.diff

LOG: [mlgo] Skip AOT-compiling a model if a header/object pair is provided

This allows one to cross-compile the header/object for a model in a
setup where the compiler is built on a system that cannot host the AOT
compiler. For example, if arm-hostable clang is desired, while the AOT
Tensorflow compiler can cross-compile to arm, it can't currently run on
arm.

The only alternative in that scenario would be to cross-compile clang
itself, but that gets complicated when trying to run tests after that.

Differential Revision: https://reviews.llvm.org/D99992

Added: 
    

Modified: 
    llvm/cmake/modules/TensorFlowCompile.cmake

Removed: 
    


################################################################################
diff  --git a/llvm/cmake/modules/TensorFlowCompile.cmake b/llvm/cmake/modules/TensorFlowCompile.cmake
index cbb450e6bf798..c4fae4f021807 100644
--- a/llvm/cmake/modules/TensorFlowCompile.cmake
+++ b/llvm/cmake/modules/TensorFlowCompile.cmake
@@ -9,27 +9,38 @@ function(tfgetmodel model final_path)
   endif()
 endfunction()
 
-# Run the tensorflow compiler (saved_model_cli) on the saved model in the 
+# Run the tensorflow compiler (saved_model_cli) on the saved model in the
 # ${model} directory, looking for the ${tag_set} tag set, and the SignatureDef
 # ${signature_def_key}.
-# Produce a pair of files called ${fname}.h and  ${fname}.o in the 
+# Produce a pair of files called ${fname}.h and  ${fname}.o in the
 # ${CMAKE_CURRENT_BINARY_DIR}. The generated header will define a C++ class
 # called ${cpp_class} - which may be a namespace-qualified class name.
 function(tfcompile model tag_set signature_def_key fname cpp_class)
-  tfgetmodel(${model} LLVM_ML_MODELS_ABSOLUTE)
-  message("Using model at " ${LLVM_ML_MODELS_ABSOLUTE})
   set(prefix ${CMAKE_CURRENT_BINARY_DIR}/${fname})
   set(obj_file ${prefix}.o)
   set(hdr_file ${prefix}.h)
-  add_custom_command(OUTPUT ${obj_file} ${hdr_file}
-    COMMAND "XLA_FLAGS=\"--xla_cpu_multi_thread_eigen=false\"" ${TENSORFLOW_AOT_COMPILER} aot_compile_cpu
-          --dir ${LLVM_ML_MODELS_ABSOLUTE}
-          --tag_set ${tag_set}
-          --signature_def_key ${signature_def_key}
-          --output_prefix ${prefix}
-          --cpp_class ${cpp_class}
-          --target_triple ${LLVM_HOST_TRIPLE}
-  )
+  string(TOUPPER ${fname} fname_allcaps)
+  set(override_header ${LLVM_OVERRIDE_MODEL_HEADER_${fname_allcaps}})
+  set(override_object ${LLVM_OVERRIDE_MODEL_OBJECT_${fname_allcaps}})
+  if (EXISTS "${override_header}" AND EXISTS "${override_object}")
+    configure_file(${override_header} ${hdr_file} COPYONLY)
+    configure_file(${override_object} ${obj_file} COPYONLY)
+    message("Using provided header "
+      ${hdr_file} " and object "   ${obj_file}
+      " files for model " ${model})
+  else()
+    tfgetmodel(${model} LLVM_ML_MODELS_ABSOLUTE)
+    message("Using model at " ${LLVM_ML_MODELS_ABSOLUTE})
+    add_custom_command(OUTPUT ${obj_file} ${hdr_file}
+      COMMAND "XLA_FLAGS=\"--xla_cpu_multi_thread_eigen=false\"" ${TENSORFLOW_AOT_COMPILER} aot_compile_cpu
+            --dir ${LLVM_ML_MODELS_ABSOLUTE}
+            --tag_set ${tag_set}
+            --signature_def_key ${signature_def_key}
+            --output_prefix ${prefix}
+            --cpp_class ${cpp_class}
+            --target_triple ${LLVM_HOST_TRIPLE}
+    )
+  endif()
 
   # Aggregate the objects so that results of 
diff erent tfcompile calls may be
   # grouped into one target.