[llvm] [MLGO] Model selection for models lowered through EmitC (PR #212650)

[Paul Kirth via llvm-commits]

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@@ -0,0 +1,123 @@
+# Compile MLGO models expressed as MLIR to C++ headers via the EmitC pipeline.
+#
+# Each entry of ${models} has the form
+# "cli-flag,path/to/model.mlir,type". Entries whose type matches
+# ${target_type} are lowered with ${mlir_opt} and translated with
+# ${mlir_translate} to a C++ header defining Model<N>, placed in
+# ${LLVM_INCLUDE_DIR}/${include_subdir}. In the same directory, generate
+# ${def_file}, with one MLGO_MODEL(ClassName, "cli-flag") entry per model, and
+# ${umbrella_header}, including all the generated model headers.
+# Append the target driving generation to MLDeps in the caller's scope, and
+# define LLVM_HAVE_EMITC_COMPILE_<TARGET_TYPE>.
+function(mlgo_compile_models models mlir_opt mlir_translate target_type
+         include_subdir def_file umbrella_header)
+  if ("${mlir_opt}" MATCHES "/")
+    get_filename_component(mlir_opt "${mlir_opt}" ABSOLUTE BASE_DIR "${CMAKE_BINARY_DIR}")
+  endif()
+  if ("${mlir_translate}" MATCHES "/")
+    get_filename_component(mlir_translate "${mlir_translate}" ABSOLUTE BASE_DIR "${CMAKE_BINARY_DIR}")
+  endif()
+
+  set(DEF_CONTENT "/* Auto-generated by CMake */\n")
+  set(DEF_CONTENT "${DEF_CONTENT}#ifndef MLGO_MODEL\n#define MLGO_MODEL(CLASS_NAME, CLI_FLAG)\n#endif\n\n")
+
+  set(HEADERS_CONTENT "/* Auto-generated by CMake */\nnamespace llvm {\n")
+  set(MLGO_GEN_TARGETS "")
+  set(MODEL_INDEX 1)
+
+  foreach(MODEL_INFO IN LISTS models)
+    # Parse comma-separated fields: cli-flag,path/to/model.mlir,type
+    string(REPLACE "," ";" MODEL_FIELDS "${MODEL_INFO}")
+    list(GET MODEL_FIELDS 0 CLI_FLAG)
+    list(GET MODEL_FIELDS 1 MODEL_PATH)
+    list(GET MODEL_FIELDS 2 MODEL_TYPE)
+
+    # Only process models matching target_type
+    if (NOT MODEL_TYPE STREQUAL target_type)
+      continue()
+    endif()
+
+    set(CLASS_NAME "Model${MODEL_INDEX}")
+    math(EXPR MODEL_INDEX "${MODEL_INDEX} + 1")
+
+    if (NOT IS_ABSOLUTE "${MODEL_PATH}")
+      get_filename_component(MODEL_PATH "${MODEL_PATH}" ABSOLUTE BASE_DIR "${CMAKE_CURRENT_SOURCE_DIR}")
+    endif()
+
+    set(EMITC_MLIR "${CMAKE_CURRENT_BINARY_DIR}/${CLASS_NAME}_emitc.mlir")
+    set(HEADER_FILE "${LLVM_INCLUDE_DIR}/${include_subdir}/${CLASS_NAME}.h")
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ilovepi wrote:

I think this probably points in to the source tree, and thus needs to be in another location, like an install dir that is included automatically. We do this with several generated files an headers in clang and llvm. I think the way this is right now would also fail on an install step, so this probably needs some tweaks to work the way you intend.

https://github.com/llvm/llvm-project/pull/212650