Removed tensorflow_c_lib_path flag from LLVM build for benchmarking (#150)

Should help with the other half of #129. The benchmarking code currently
sets the TENSORFLOW_C_LIB_PATH CMake variable when building LLVM.
However, this doesn't make sense going forward as we have shifted mostly
everything over to TFLite and we don't need to have MLGO development
mode enabled for benchmarking in either case. This patch explicitly
removes the flag so that the benchmarks simply build LLVM in MLGO
release mode.

compiler_opt/benchmark/benchmark_chromium.py

diff --git a/compiler_opt/benchmark/benchmark_chromium.py b/compiler_opt/benchmark/benchmark_chromium.py
index bc1379f..3f69965 100644
--- a/compiler_opt/benchmark/benchmark_chromium.py
+++ b/compiler_opt/benchmark/benchmark_chromium.py
@@ -30,7 +30,6 @@
   --llvm_build_path=/llvm-build \
   --compile_llvm \
   --model_path=/tmp/model \
-  --tensorflow_c_lib_path=/tmp/tensorflow \
   --chromium_build_path=./out/Release \
   --output_file=./output.json \
   --perf_counters=mem_uops_retired.all_loads \
@@ -90,9 +89,6 @@
 flags.DEFINE_string('model_path', '',
                     'The path to the model to use when compiling llvm')
 flags.DEFINE_string(
-    'tensorflow_c_lib_path', '/tmp/tensorflow',
-    'The path to an extracted copy of the tensorflow c library')
-flags.DEFINE_string(
     'chromium_build_path', './out/Release',
     'The chromium build path, relative to the chromium source'
     'directory')
@@ -210,8 +206,7 @@
 
   if FLAGS.compile_llvm:
     benchmarking_utils.build_llvm(FLAGS.model_path, FLAGS.llvm_use_incremental,
-                                  FLAGS.llvm_build_path, FLAGS.llvm_source_path,
-                                  FLAGS.tensorflow_c_lib_path)
+                                  FLAGS.llvm_build_path, FLAGS.llvm_source_path)
 
   if FLAGS.compile_tests:
     build_chromium_tests(FLAGS.advisor, FLAGS.chromium_build_path,

compiler_opt/benchmark/benchmark_llvm_test_suite.py

diff --git a/compiler_opt/benchmark/benchmark_llvm_test_suite.py b/compiler_opt/benchmark/benchmark_llvm_test_suite.py
index 0f5bce5..fc7ad3d 100644
--- a/compiler_opt/benchmark/benchmark_llvm_test_suite.py
+++ b/compiler_opt/benchmark/benchmark_llvm_test_suite.py
@@ -33,7 +33,6 @@
   --llvm_build_path=/llvm-build \
   --llvm_source_path=/llvm-project \
   --llvm_test_suite_build_path=/llvm-test-suite/build \
-  --tensorflow_c_lib_path=/tmp/tensorflow \
   --perf_counter=INSTRUCTIONS \
   --perf_counter=MEM_UOPS_RETIRED:ALL_LOADS \
   --perf_counter=MEM_UOPS_RETIRED:ALL_STORES
@@ -96,8 +95,6 @@
                     'The path to the root of the llvm-project repositoy')
 flags.DEFINE_string('llvm_test_suite_build_path', None,
                     'The path to the llvm test suite build')
-flags.DEFINE_string('tensorflow_c_lib_path', '/tmp/tensorflow',
-                    'The path to the tensorflow c lib library')
 flags.DEFINE_multi_string(
     'tests_to_run', default_tests,
     'Tests compiled with google benchmark to run,'
@@ -189,8 +186,7 @@
                                                     './build')
   if FLAGS.compile_llvm:
     benchmarking_utils.build_llvm(FLAGS.model_path, FLAGS.llvm_use_incremental,
-                                  FLAGS.llvm_build_path, FLAGS.llvm_source_path,
-                                  FLAGS.tensorflow_c_lib_path)
+                                  FLAGS.llvm_build_path, FLAGS.llvm_source_path)
   if FLAGS.compile_testsuite:
     build_test_suite(FLAGS.advisor, FLAGS.llvm_test_suite_build_path,
                      FLAGS.llvm_build_path, FLAGS.llvm_test_suite_path)

compiler_opt/benchmark/benchmarking_utils.py

diff --git a/compiler_opt/benchmark/benchmarking_utils.py b/compiler_opt/benchmark/benchmarking_utils.py
index 26c17d4..79bd55b 100644
--- a/compiler_opt/benchmark/benchmarking_utils.py
+++ b/compiler_opt/benchmark/benchmarking_utils.py
@@ -25,8 +25,7 @@
 
 
 def build_llvm(model_path: str, use_existing_build: bool, llvm_build_path: str,
-               llvm_source_path: Optional[str],
-               tensorflow_c_lib_path: Optional[str]):
+               llvm_source_path: Optional[str]):
   """Builds LLVM/clang with the specified model and the correct settings
 
   This function invokes CMake with all the correct build flags specified
@@ -60,9 +59,7 @@
     tensorflow_aot_path = os.path.dirname(tensorflow.__file__)
     cmake_config_command.extend([
         "-DCMAKE_BUILD_TYPE=Release",
-        f"-DTENSORFLOW_C_LIB_PATH={tensorflow_c_lib_path}",
         f"-DTENSORFLOW_AOT_PATH='{tensorflow_aot_path}'",
-        "-DCMAKE_INSTALL_RPATH_USE_LINK_PATH=ON",
         "-DLLVM_ENABLE_PROJECTS='clang;lld'",
         "-DLLVM_ENABLE_RUNTIMES='compiler-rt'", f"{llvm_source_path}"
     ])