Tidy up CMake style across the project. (#9000)

This change _should_ be an NFC, just going through and aligning our CMake files on a consistent style for items like:

* No spaces between commands and the opening parenthesis: use `if(...)`, instead of `if (...)`
* No variable references when not needed: use `if(VARIABLE_NAME)` / `if(NOT VARIABLE_NAME)`, instead of `if(${VARIABLE_NAME})` / `if(NOT ${VARIABLE_NAME})`
* Local variables use `_UPPER_CASE`, instead of `_lower_case` or `UPPER_CASE`
* Parsed arguments use the `_RULE` prefix, not `ARG` (LLVM mostly uses `ARG`, but we've been using `_RULE`)

Individual commits have the details for how they were generated (surprise surprise, it's a pile of regex find/replaces with some manual cleanup sprinkled on top), as well as the rationale where applicable. I may have missed some cases in my search, and we have no automated formatting or enforcement.

---

Inspired by https://github.com/google/iree/pull/8933#discussion_r853526858:

> Use if(IREE_ENABLE_CPUINFO)
> (we're super inconsistent on this but I try to get it right going forward)
diff --git a/build_tools/cmake/external_cc_library.cmake b/build_tools/cmake/external_cc_library.cmake
index 9b1fde2..571a1be 100644
--- a/build_tools/cmake/external_cc_library.cmake
+++ b/build_tools/cmake/external_cc_library.cmake
@@ -93,9 +93,9 @@
   # 16.04 LTS) only come with cmake 3.5 by default.  For this reason, we can't
   # use list(FILTER...)
   set(_CC_SRCS "${_RULE_SRCS}")
-  foreach(src_file IN LISTS _CC_SRCS)
-    if(${src_file} MATCHES ".*\\.(h|inc)")
-      list(REMOVE_ITEM _CC_SRCS "${src_file}")
+  foreach(_SRC_FILE IN LISTS _CC_SRCS)
+    if(${_SRC_FILE} MATCHES ".*\\.(h|inc)")
+      list(REMOVE_ITEM _CC_SRCS "${_SRC_FILE}")
     endif()
   endforeach()
   if("${_CC_SRCS}" STREQUAL "")
diff --git a/build_tools/cmake/iree_benchmark_suite.cmake b/build_tools/cmake/iree_benchmark_suite.cmake
index f065500..ef67d7b 100644
--- a/build_tools/cmake/iree_benchmark_suite.cmake
+++ b/build_tools/cmake/iree_benchmark_suite.cmake
@@ -115,7 +115,7 @@
       # Strip off gzip suffix if present (downloader unzips if necessary)
       string(REGEX REPLACE "\.gz$" "" _SOURCE_FILE_BASENAME "${_LAST_URL_SEGMENT}")
       set(_MODULE_SOURCE "${_ROOT_ARTIFACTS_DIR}/${_SOURCE_FILE_BASENAME}")
-      if (NOT TARGET "${_DOWNLOAD_TARGET}")
+      if(NOT TARGET "${_DOWNLOAD_TARGET}")
         add_custom_command(
           OUTPUT "${_MODULE_SOURCE}"
           COMMAND
@@ -134,7 +134,7 @@
 
     # If the source is a TFLite file, import it.
     if("${_MODULE_SOURCE}" MATCHES "\.tflite$")
-      if (NOT IREE_IMPORT_TFLITE_PATH)
+      if(NOT IREE_IMPORT_TFLITE_PATH)
         message(SEND_ERROR "Benchmarks of ${_MODULE_SOURCE} require"
                           " that iree-import-tflite be available "
                           " (either on PATH or via IREE_IMPORT_TFLITE_PATH)")
@@ -143,7 +143,7 @@
       set(_MODULE_SOURCE "${_TFLITE_FILE}.mlir")
       get_filename_component(_TFLITE_FILE_BASENAME "${_TFLITE_FILE}" NAME)
       set(_TFLITE_IMPORT_TARGET "${PACKAGE_NAME}_iree-import-tflite-${_TFLITE_FILE_BASENAME}")
-      if (NOT TARGET "${_TFLITE_IMPORT_TARGET}")
+      if(NOT TARGET "${_TFLITE_IMPORT_TARGET}")
         add_custom_command(
           OUTPUT "${_MODULE_SOURCE}"
           COMMAND
@@ -168,7 +168,7 @@
     # Next create the command and target for compiling the input module into
     # IREE deployable format for each benchmark mode.
     string(JOIN "-" _MODULE_DIR_NAME "${_MODULE_NAME}" "${_MODULE_TAGS}")
-    foreach (_BENCHMARK_MODE IN LISTS _RULE_BENCHMARK_MODES)
+    foreach(_BENCHMARK_MODE IN LISTS _RULE_BENCHMARK_MODES)
       set(_BENCHMARK_DIR_NAME
           "iree-${_RULE_DRIVER}__${_RULE_TARGET_ARCHITECTURE}__${_BENCHMARK_MODE}")
 
@@ -237,7 +237,7 @@
         add_dependencies(iree-benchmark-suites "${_TRANSLATION_TARGET_NAME}")
       endif(NOT TARGET "${_TRANSLATION_TARGET_NAME}")
 
-      if (NOT TARGET "${_FRIENDLY_TARGET_NAME}")
+      if(NOT TARGET "${_FRIENDLY_TARGET_NAME}")
         add_custom_target("${_FRIENDLY_TARGET_NAME}")
       endif()
       add_dependencies("${_FRIENDLY_TARGET_NAME}" "${_TRANSLATION_TARGET_NAME}")
diff --git a/build_tools/cmake/iree_c_embed_data.cmake b/build_tools/cmake/iree_c_embed_data.cmake
index 9cb3ec1..01294f5 100644
--- a/build_tools/cmake/iree_c_embed_data.cmake
+++ b/build_tools/cmake/iree_c_embed_data.cmake
@@ -53,20 +53,20 @@
   if(DEFINED _RULE_STRIP_PREFIX)
     list(APPEND _ARGS "--strip_prefix=${_RULE_STRIP_PREFIX}")
   endif()
-  if(${_RULE_FLATTEN})
+  if(_RULE_FLATTEN)
     list(APPEND _ARGS "--flatten")
   endif()
 
-  foreach(SRC ${_RULE_SRCS})
-    if(IS_ABSOLUTE "${SRC}")
-      list(APPEND _ARGS "${SRC}")
+  foreach(_SRC ${_RULE_SRCS})
+    if(IS_ABSOLUTE "${_SRC}")
+      list(APPEND _ARGS "${_SRC}")
     else()
-      list(APPEND _ARGS "${CMAKE_CURRENT_SOURCE_DIR}/${SRC}")
+      list(APPEND _ARGS "${CMAKE_CURRENT_SOURCE_DIR}/${_SRC}")
     endif()
-  endforeach(SRC)
-  foreach(SRC ${_RULE_GENERATED_SRCS})
-    list(APPEND _ARGS "${SRC}")
-  endforeach(SRC)
+  endforeach(_SRC)
+  foreach(_SRC ${_RULE_GENERATED_SRCS})
+    list(APPEND _ARGS "${_SRC}")
+  endforeach(_SRC)
 
   iree_get_executable_path(_EXE_PATH generate_embed_data)
 
diff --git a/build_tools/cmake/iree_cc_binary_benchmark.cmake b/build_tools/cmake/iree_cc_binary_benchmark.cmake
index 03eacda..13e230a 100644
--- a/build_tools/cmake/iree_cc_binary_benchmark.cmake
+++ b/build_tools/cmake/iree_cc_binary_benchmark.cmake
@@ -44,12 +44,12 @@
   )
 
   set(_MAYBE_TESTONLY "")
-  if (_RULE_TESTONLY)
+  if(_RULE_TESTONLY)
     set(_MAYBE_TESTONLY "TESTONLY")
   endif()
 
   set(_MAYBE_HOSTONLY "")
-  if (_RULE_HOSTONLY)
+  if(_RULE_HOSTONLY)
     set(_MAYBE_HOSTONLY "HOSTONLY")
   endif()
 
diff --git a/build_tools/cmake/iree_cc_library.cmake b/build_tools/cmake/iree_cc_library.cmake
index 9afb144..4a9a9c2 100644
--- a/build_tools/cmake/iree_cc_library.cmake
+++ b/build_tools/cmake/iree_cc_library.cmake
@@ -84,9 +84,9 @@
   # 16.04 LTS) only come with cmake 3.5 by default.  For this reason, we can't
   # use list(FILTER...)
   set(_CC_SRCS "${_RULE_SRCS}")
-  foreach(src_file IN LISTS _CC_SRCS)
-    if(${src_file} MATCHES ".*\\.(h|inc)")
-      list(REMOVE_ITEM _CC_SRCS "${src_file}")
+  foreach(_SRC_FILE IN LISTS _CC_SRCS)
+    if(${_SRC_FILE} MATCHES ".*\\.(h|inc)")
+      list(REMOVE_ITEM _CC_SRCS "${_SRC_FILE}")
     endif()
   endforeach()
   if("${_CC_SRCS}" STREQUAL "")
@@ -255,20 +255,20 @@
 #     targets that are not under teh "iree::" namespace but are encountered
 #     in the dependency dag.
 function(_iree_cc_library_add_object_deps name)
-  foreach(dep_target ${ARGN})
-    if(dep_target MATCHES "^iree::")
+  foreach(_DEP_TARGET ${ARGN})
+    if(_DEP_TARGET MATCHES "^iree::")
       set_property(TARGET ${name} APPEND PROPERTY
         INTERFACE_IREE_TRANSITIVE_OBJECTS
-        "$<GENEX_EVAL:$<TARGET_PROPERTY:${dep_target},INTERFACE_IREE_TRANSITIVE_OBJECTS>>"
+        "$<GENEX_EVAL:$<TARGET_PROPERTY:${_DEP_TARGET},INTERFACE_IREE_TRANSITIVE_OBJECTS>>"
       )
       set_property(TARGET ${name} APPEND PROPERTY
       INTERFACE_IREE_TRANSITIVE_OBJECT_LIBS
-        "$<GENEX_EVAL:$<TARGET_PROPERTY:${dep_target},INTERFACE_IREE_TRANSITIVE_OBJECT_LIBS>>"
+        "$<GENEX_EVAL:$<TARGET_PROPERTY:${_DEP_TARGET},INTERFACE_IREE_TRANSITIVE_OBJECT_LIBS>>"
       )
     else()
       set_property(TARGET ${name} APPEND PROPERTY
         INTERFACE_IREE_TRANSITIVE_OBJECT_LIBS
-        ${dep_target}
+        ${_DEP_TARGET}
       )
     endif()
   endforeach()
@@ -312,21 +312,21 @@
   set(_NAME "${_PACKAGE_NAME}_${_RULE_NAME}")
 
   # Evaluate the object and libs.
-  set(_objects "$<REMOVE_DUPLICATES:$<GENEX_EVAL:$<TARGET_PROPERTY:${_RULE_ROOT},INTERFACE_IREE_TRANSITIVE_OBJECTS>>>")
-  set(_libs "$<REMOVE_DUPLICATES:$<GENEX_EVAL:$<TARGET_PROPERTY:${_RULE_ROOT},INTERFACE_IREE_TRANSITIVE_OBJECT_LIBS>>>")
+  set(_OBJECTS "$<REMOVE_DUPLICATES:$<GENEX_EVAL:$<TARGET_PROPERTY:${_RULE_ROOT},INTERFACE_IREE_TRANSITIVE_OBJECTS>>>")
+  set(_LIBS "$<REMOVE_DUPLICATES:$<GENEX_EVAL:$<TARGET_PROPERTY:${_RULE_ROOT},INTERFACE_IREE_TRANSITIVE_OBJECT_LIBS>>>")
 
   # For debugging, write out evaluated objects to a file.
   file(GENERATE OUTPUT "${_RULE_NAME}.contents.txt" CONTENT
-    "OBJECTS:\n${_objects}\n\nLIBS:\n${_libs}\n")
+    "OBJECTS:\n${_OBJECTS}\n\nLIBS:\n${_LIBS}\n")
   if(_RULE_SHARED)
-    add_library(${_NAME} SHARED ${_objects})
+    add_library(${_NAME} SHARED ${_OBJECTS})
   else()
-    add_library(${_NAME} STATIC ${_objects})
+    add_library(${_NAME} STATIC ${_OBJECTS})
   endif()
 
   target_link_libraries(${_NAME}
     PUBLIC
-      ${_libs}
+      ${_LIBS}
   )
 
   # Forward compile usage requirements from the root library.
diff --git a/build_tools/cmake/iree_check_test.cmake b/build_tools/cmake/iree_check_test.cmake
index 4c6224a..a65b6c1 100644
--- a/build_tools/cmake/iree_check_test.cmake
+++ b/build_tools/cmake/iree_check_test.cmake
@@ -319,22 +319,22 @@
   set(_TARGET_CPU_FEATURES "" PARENT_SCOPE)
   set(_TARGET_CPU_FEATURES_SUFFIX "" PARENT_SCOPE)
   set(_TARGET_PASS_OPTIONS "" PARENT_SCOPE)
-  if ("${_INPUT_TARGET_CPU_FEATURES}" STREQUAL "default")
+  if("${_INPUT_TARGET_CPU_FEATURES}" STREQUAL "default")
     set(_ENABLED "TRUE" PARENT_SCOPE)
     set(_TARGET_PASS_OPTIONS "arch=${CMAKE_SYSTEM_PROCESSOR}" PARENT_SCOPE)
     return()
   endif()
   string(REGEX MATCHALL "[^:]+" _COMPONENTS "${_INPUT_TARGET_CPU_FEATURES}")
   list(LENGTH _COMPONENTS _NUM_COMPONENTS)
-  if (NOT _NUM_COMPONENTS EQUAL 2)
-    message (SEND_ERROR "TARGET_CPU_FEATURES should be of the form \
+  if(NOT _NUM_COMPONENTS EQUAL 2)
+    message(SEND_ERROR "TARGET_CPU_FEATURES should be of the form \
 _FILTER_ARCH:_TARGET_CPU_FEATURES. Got: ${_INPUT_TARGET_CPU_FEATURES}")
     return()
   endif()
   # TARGET_CPU_FEATURES_VARIANT is of the form _FILTER_ARCH:_TARGET_CPU_FEATURE.
   list(GET _COMPONENTS 0 _FILTER_ARCH)
   list(GET _COMPONENTS 1 _TARGET_CPU_FEATURES)
-  if (_FILTER_ARCH STREQUAL CMAKE_SYSTEM_PROCESSOR)
+  if(_FILTER_ARCH STREQUAL CMAKE_SYSTEM_PROCESSOR)
     set(_ENABLED "TRUE" PARENT_SCOPE)
     set(_TARGET_CPU_FEATURES "${_TARGET_CPU_FEATURES}" PARENT_SCOPE)
     # TODO: the logic to generate the suffix from the list of target CPU features
@@ -343,17 +343,17 @@
     # any character that's not wanted in a cmake rule name.
     # For now, let's just generate errors in those cases:
     list(LENGTH _TARGET_CPU_FEATURES _NUM_TARGET_CPU_FEATURES)
-    if (NOT _NUM_TARGET_CPU_FEATURES EQUAL 1)
+    if(NOT _NUM_TARGET_CPU_FEATURES EQUAL 1)
       message(SEND_ERROR "Current limitation: \
 TARGET_CPU_FEATURES should have length 1")
     endif()
     string(SUBSTRING "${_TARGET_CPU_FEATURES}" 0 1 _TARGET_CPU_FEATURES_FIRST_CHAR)
     string(SUBSTRING "${_TARGET_CPU_FEATURES}" 1 -1 _TARGET_CPU_FEATURES_AFTER_FIRST_CHAR)
-    if (NOT _TARGET_CPU_FEATURES_FIRST_CHAR STREQUAL "+")
+    if(NOT _TARGET_CPU_FEATURES_FIRST_CHAR STREQUAL "+")
       message(SEND_ERROR "Current limitation: \
 TARGET_CPU_FEATURES should start with a +. Got: ${_TARGET_CPU_FEATURES}.")
     endif()
-    if (NOT _TARGET_CPU_FEATURES_AFTER_FIRST_CHAR MATCHES "[a-zA-Z0-9_]+")
+    if(NOT _TARGET_CPU_FEATURES_AFTER_FIRST_CHAR MATCHES "[a-zA-Z0-9_]+")
       message(SEND_ERROR "Current limitation: \
 TARGET_CPU_FEATURES should match [a-zA-Z0-9]+ after the initial +. \
 Got: ${_TARGET_CPU_FEATURES}.")
@@ -427,7 +427,7 @@
   foreach(_INDEX RANGE "${_MAX_INDEX}")
     list(GET _RULE_TARGET_BACKENDS ${_INDEX} _TARGET_BACKEND)
     list(GET _RULE_DRIVERS ${_INDEX} _DRIVER)
-    if (_TARGET_BACKEND STREQUAL "dylib-llvm-aot" AND _RULE_TARGET_CPU_FEATURES_VARIANTS)
+    if(_TARGET_BACKEND STREQUAL "dylib-llvm-aot" AND _RULE_TARGET_CPU_FEATURES_VARIANTS)
       set(_TARGET_CPU_FEATURES_VARIANTS "${_RULE_TARGET_CPU_FEATURES_VARIANTS}")
     else()
       set(_TARGET_CPU_FEATURES_VARIANTS "default")
@@ -435,7 +435,7 @@
     foreach(_TARGET_CPU_FEATURES_LIST_ELEM IN LISTS _TARGET_CPU_FEATURES_VARIANTS)
       process_target_cpu_features("${_TARGET_CPU_FEATURES_LIST_ELEM}" _ENABLED _TARGET_CPU_FEATURES _TARGET_CPU_FEATURES_SUFFIX _TARGET_PASS_OPTIONS)
       string(REPLACE "#pass_options_variant#" "${_TARGET_PASS_OPTIONS}" _PROCESSED_COMPILER_FLAGS "${_RULE_COMPILER_FLAGS}")
-      if (NOT _ENABLED)
+      if(NOT _ENABLED)
         # The current entry is disabled on the target CPU architecture.
         continue()
       endif()
diff --git a/build_tools/cmake/iree_copts.cmake b/build_tools/cmake/iree_copts.cmake
index 89955ab..6d4a120 100644
--- a/build_tools/cmake/iree_copts.cmake
+++ b/build_tools/cmake/iree_copts.cmake
@@ -271,7 +271,7 @@
 
 # Set some things back to warnings that are really annoying as build errors
 # during active development (but we still want as errors on CI).
-if (IREE_DEV_MODE)
+if(IREE_DEV_MODE)
   iree_select_compiler_opts(IREE_DEFAULT_COPTS
     CLANG_OR_GCC
       "-Wno-error=unused-parameter"
@@ -350,7 +350,7 @@
 #-------------------------------------------------------------------------------
 
 # TODO(#898): add a dedicated size-constrained configuration.
-if(${IREE_SIZE_OPTIMIZED})
+if(IREE_SIZE_OPTIMIZED)
   iree_select_compiler_opts(IREE_SIZE_OPTIMIZED_DEFAULT_COPTS
     MSVC_OR_CLANG_CL
       "/GS-"
diff --git a/build_tools/cmake/iree_macros.cmake b/build_tools/cmake/iree_macros.cmake
index ccb9c9b..c205279 100644
--- a/build_tools/cmake/iree_macros.cmake
+++ b/build_tools/cmake/iree_macros.cmake
@@ -132,7 +132,7 @@
 #     the binary when importing a binary from a host build. Thus this should be
 #     the global unqualified name of the binary, not the fully-specified name.
 function(iree_get_executable_path OUTPUT_PATH_VAR EXECUTABLE)
-  if (NOT DEFINED IREE_HOST_BINARY_ROOT OR TARGET "${EXECUTABLE}")
+  if(NOT DEFINED IREE_HOST_BINARY_ROOT OR TARGET "${EXECUTABLE}")
     # We can either expect the target to be defined as part of this CMake
     # invocation (if not cross compiling) or the target is defined already.
     set(${OUTPUT_PATH_VAR} "$<TARGET_FILE:${EXECUTABLE}>" PARENT_SCOPE)
@@ -141,7 +141,7 @@
     # for an already built executable at IREE_HOST_BINARY_ROOT. If we find it,
     # add it as an imported target so it gets picked up on later invocations.
     set(_EXECUTABLE_PATH "${IREE_HOST_BINARY_ROOT}/bin/${EXECUTABLE}${IREE_HOST_EXECUTABLE_SUFFIX}")
-    if (EXISTS ${_EXECUTABLE_PATH})
+    if(EXISTS ${_EXECUTABLE_PATH})
       add_executable("${EXECUTABLE}" IMPORTED GLOBAL)
       set_property(TARGET "${EXECUTABLE}" PROPERTY IMPORTED_LOCATION "${_EXECUTABLE_PATH}")
       set(${OUTPUT_PATH_VAR} "$<TARGET_FILE:${EXECUTABLE}>" PARENT_SCOPE)
@@ -214,7 +214,7 @@
 #
 # Parameters:
 # NAME: name of the target to add data dependencies to
-# DATA: List of targets and/or files in the source tree (relative to the 
+# DATA: List of targets and/or files in the source tree (relative to the
 # project root).
 function(iree_add_data_dependencies)
   cmake_parse_arguments(
@@ -271,7 +271,7 @@
 #   TO_EXE_NAME: The executable name to output in the current binary dir.
 function(iree_symlink_tool)
   cmake_parse_arguments(
-    ARG
+    _RULE
     ""
     "TARGET;FROM_TOOL_TARGET;TO_EXE_NAME"
     ""
@@ -281,16 +281,16 @@
   # Transform TARGET
   iree_package_ns(_PACKAGE_NS)
   iree_package_name(_PACKAGE_NAME)
-  set(_TARGET "${_PACKAGE_NAME}_${ARG_TARGET}")
-  set(_FROM_TOOL_TARGET ${ARG_FROM_TOOL_TARGET})
-  set(_TO_TOOL_PATH "${CMAKE_CURRENT_BINARY_DIR}/${ARG_TO_EXE_NAME}${CMAKE_EXECUTABLE_SUFFIX}")
+  set(_TARGET "${_PACKAGE_NAME}_${_RULE_TARGET}")
+  set(_FROM_TOOL_TARGET ${_RULE_FROM_TOOL_TARGET})
+  set(_TO_TOOL_PATH "${CMAKE_CURRENT_BINARY_DIR}/${_RULE_TO_EXE_NAME}${CMAKE_EXECUTABLE_SUFFIX}")
   get_filename_component(_TO_TOOL_DIR "${_TO_TOOL_PATH}" DIRECTORY)
 
 
   add_custom_command(
     TARGET "${_TARGET}"
     BYPRODUCTS
-      "${CMAKE_CURRENT_BINARY_DIR}/${ARG_TO_EXE_NAME}${CMAKE_EXECUTABLE_SUFFIX}"
+      "${CMAKE_CURRENT_BINARY_DIR}/${_RULE_TO_EXE_NAME}${CMAKE_EXECUTABLE_SUFFIX}"
     COMMAND
       ${CMAKE_COMMAND} -E make_directory "${_TO_TOOL_DIR}"
     COMMAND
@@ -321,7 +321,7 @@
   #
   # Tests which only depend on a compiler target backend or a runtime HAL
   # driver, but not both, should generally use a different method of filtering.
-  if(NOT "${IREE_TARGET_BACKEND_VULKAN_SPIRV}" OR NOT "${IREE_HAL_DRIVER_VULKAN}")
+  if(NOT IREE_TARGET_BACKEND_VULKAN_SPIRV OR NOT IREE_HAL_DRIVER_VULKAN)
     set_property(TEST ${TEST_NAME} APPEND PROPERTY ENVIRONMENT "IREE_VULKAN_DISABLE=1")
   endif()
 endfunction()
diff --git a/build_tools/cmake/iree_native_test.cmake b/build_tools/cmake/iree_native_test.cmake
index 7a6ddcb..dd1d872 100644
--- a/build_tools/cmake/iree_native_test.cmake
+++ b/build_tools/cmake/iree_native_test.cmake
@@ -68,7 +68,7 @@
   set(_TEST_NAME "${_PACKAGE_PATH}/${_RULE_NAME}")
 
   # If driver was specified, add the corresponding test arg and label.
-  if (DEFINED _RULE_DRIVER)
+  if(DEFINED _RULE_DRIVER)
     list(APPEND _RULE_ARGS "--driver=${_RULE_DRIVER}")
     list(APPEND _RULE_LABELS "driver=${_RULE_DRIVER}")
   endif()
@@ -77,8 +77,8 @@
     set(_ANDROID_ABS_DIR "/data/local/tmp/${_PACKAGE_PATH}/${_RULE_NAME}")
   endif()
 
-  if (DEFINED _RULE_TEST_INPUT_FILE_ARG)
-    if (ANDROID)
+  if(DEFINED _RULE_TEST_INPUT_FILE_ARG)
+    if(ANDROID)
       get_filename_component(_TEST_INPUT_FILE_BASENAME "${_RULE_TEST_INPUT_FILE_ARG}" NAME)
       list(APPEND _RULE_ARGS "${_ANDROID_ABS_DIR}/${_TEST_INPUT_FILE_BASENAME}")
     else()
@@ -104,7 +104,7 @@
     # Use environment variables to instruct the script to push artifacts
     # onto the Android device before running the test. This needs to match
     # with the expectation of the run_android_test.{sh|bat|ps1} script.
-    string (REPLACE ";" " " _DATA_SPACE_SEPARATED "${_RULE_DATA}")
+    string(REPLACE ";" " " _DATA_SPACE_SEPARATED "${_RULE_DATA}")
     set(
       _ENVIRONMENT_VARS
         "TEST_ANDROID_ABS_DIR=${_ANDROID_ABS_DIR}"
diff --git a/build_tools/cmake/iree_python.cmake b/build_tools/cmake/iree_python.cmake
index 64e9143..0dc833b 100644
--- a/build_tools/cmake/iree_python.cmake
+++ b/build_tools/cmake/iree_python.cmake
@@ -70,27 +70,26 @@
     "COMPONENT;PACKAGE_NAME;MODULE_PATH"
     "DEPS;ADDL_PACKAGE_FILES;FILES_MATCHING"
     ${ARGN})
-  set(_install_component ${ARG_COMPONENT})
-  set(_install_packages_dir "python_packages/${ARG_PACKAGE_NAME}")
-  set(_install_module_dir "${_install_packages_dir}/${ARG_MODULE_PATH}")
-  set(_target_name install-${_install_component})
+  set(_INSTALL_COMPONENT ${ARG_COMPONENT})
+  set(_INSTALL_PACKAGES_DIR "python_packages/${ARG_PACKAGE_NAME}")
+  set(_INSTALL_MODULE_DIR "${_INSTALL_PACKAGES_DIR}/${ARG_MODULE_PATH}")
 
   if(NOT FILES_MATCHING)
-    set(_files_matching PATTERN "*.py")
+    set(_FILES_MATCHING PATTERN "*.py")
   else()
-    set(_files_matching ${ARG_FILES_MATCHING})
+    set(_FILES_MATCHING ${ARG_FILES_MATCHING})
   endif()
 
   install(
     DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/
-    COMPONENT ${_install_component}
-    DESTINATION "${_install_module_dir}"
-    FILES_MATCHING ${_files_matching}
+    COMPONENT ${_INSTALL_COMPONENT}
+    DESTINATION "${_INSTALL_MODULE_DIR}"
+    FILES_MATCHING ${_FILES_MATCHING}
   )
 
-  set(PY_INSTALL_COMPONENT ${_install_component} PARENT_SCOPE)
-  set(PY_INSTALL_PACKAGES_DIR "${_install_packages_dir}" PARENT_SCOPE)
-  set(PY_INSTALL_MODULE_DIR "${_install_module_dir}" PARENT_SCOPE)
+  set(PY_INSTALL_COMPONENT ${_INSTALL_COMPONENT} PARENT_SCOPE)
+  set(PY_INSTALL_PACKAGES_DIR "${_INSTALL_PACKAGES_DIR}" PARENT_SCOPE)
+  set(PY_INSTALL_MODULE_DIR "${_INSTALL_MODULE_DIR}" PARENT_SCOPE)
 endfunction()
 
 # iree_pyext_module()
@@ -204,7 +203,7 @@
 # PYEXT_DEPS: List of deps of extensions built with iree_pyext_module
 function(iree_py_library)
   cmake_parse_arguments(
-    ARG
+    _RULE
     ""
     "NAME"
     "SRCS;DEPS;PYEXT_DEPS"
@@ -213,36 +212,36 @@
 
   iree_package_ns(_PACKAGE_NS)
   # Replace dependencies passed by ::name with ::iree::package::name
-  list(TRANSFORM ARG_DEPS REPLACE "^::" "${_PACKAGE_NS}::")
+  list(TRANSFORM _RULE_DEPS REPLACE "^::" "${_PACKAGE_NS}::")
 
   iree_package_name(_PACKAGE_NAME)
-  set(_NAME "${_PACKAGE_NAME}_${ARG_NAME}")
+  set(_NAME "${_PACKAGE_NAME}_${_RULE_NAME}")
 
   add_custom_target(${_NAME} ALL
-    DEPENDS ${ARG_DEPS}
+    DEPENDS ${_RULE_DEPS}
   )
 
   # Symlink each file as its own target.
-  foreach(SRC_FILE ${ARG_SRCS})
-    # SRC_FILE could have other path components in it, so we need to make a
+  foreach(_SRC_FILE ${_RULE_SRCS})
+    # _SRC_FILE could have other path components in it, so we need to make a
     # directory for it. Ninja does this automatically, but make doesn't. See
     # https://github.com/google/iree/issues/6801
-    set(_SRC_BIN_PATH "${CMAKE_CURRENT_BINARY_DIR}/${SRC_FILE}")
+    set(_SRC_BIN_PATH "${CMAKE_CURRENT_BINARY_DIR}/${_SRC_FILE}")
     get_filename_component(_SRC_BIN_DIR "${_SRC_BIN_PATH}" DIRECTORY)
     add_custom_command(
       TARGET ${_NAME}
       COMMAND
         ${CMAKE_COMMAND} -E make_directory "${_SRC_BIN_DIR}"
       COMMAND ${CMAKE_COMMAND} -E create_symlink
-        "${CMAKE_CURRENT_SOURCE_DIR}/${SRC_FILE}" "${_SRC_BIN_PATH}"
+        "${CMAKE_CURRENT_SOURCE_DIR}/${_SRC_FILE}" "${_SRC_BIN_PATH}"
       BYPRODUCTS "${_SRC_BIN_PATH}"
     )
   endforeach()
 
   # Add PYEXT_DEPS if any.
-  if(ARG_PYEXT_DEPS)
-    list(TRANSFORM ARG_PYEXT_DEPS REPLACE "^::" "${_PACKAGE_NS}::")
-    add_dependencies(${_NAME} ${ARG_PYEXT_DEPS})
+  if(_RULE_PYEXT_DEPS)
+    list(TRANSFORM _RULE_PYEXT_DEPS REPLACE "^::" "${_PACKAGE_NS}::")
+    add_dependencies(${_NAME} ${_RULE_PYEXT_DEPS})
   endif()
 endfunction()
 
diff --git a/build_tools/cmake/iree_setup_toolchain.cmake b/build_tools/cmake/iree_setup_toolchain.cmake
index fd63cd0..e15779e 100644
--- a/build_tools/cmake/iree_setup_toolchain.cmake
+++ b/build_tools/cmake/iree_setup_toolchain.cmake
@@ -5,9 +5,9 @@
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
 function(iree_append value)
-  foreach(variable ${ARGN})
-    set(${variable} "${${variable}} ${value}" PARENT_SCOPE)
-  endforeach(variable)
+  foreach(_VARIABLE ${ARGN})
+    set(${_VARIABLE} "${${_VARIABLE}} ${value}" PARENT_SCOPE)
+  endforeach(_VARIABLE)
 endfunction()
 
 if(IREE_ENABLE_LLD)
@@ -24,7 +24,7 @@
   # argument warning about -fuse-ld, which can foul up compiler flag detection,
   # causing false negatives. We lack a finer grained way to suppress such a
   # thing, and this is deemed least bad.
-  if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+  if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
     iree_append("-Wno-unused-command-line-argument"
       CMAKE_REQUIRED_FLAGS
       CMAKE_EXE_LINKER_FLAGS
diff --git a/build_tools/cmake/iree_test_matrix.cmake b/build_tools/cmake/iree_test_matrix.cmake
index 9a8aba4..b2d0afe 100644
--- a/build_tools/cmake/iree_test_matrix.cmake
+++ b/build_tools/cmake/iree_test_matrix.cmake
@@ -18,18 +18,17 @@
 # TODO: Add a `generate` step conditioned on the test_matrix.yaml file, so that
 # reconfigure is automatic.
 function(iree_test_matrix_gen)
-  set(_test_matrix_yaml "${CMAKE_CURRENT_SOURCE_DIR}/test_matrix.yaml")
-  set(_generator_script "${PROJECT_SOURCE_DIR}/build_tools/testing/gen_test_matrix.py")
+  set(_GENERATOR_SCRIPT "${PROJECT_SOURCE_DIR}/build_tools/testing/gen_test_matrix.py")
   message(STATUS "Generating tests for ${CMAKE_CURRENT_SOURCE_DIR}")
   execute_process(
     COMMAND "${Python3_EXECUTABLE}"
-      "${_generator_script}"
+      "${_GENERATOR_SCRIPT}"
       --dir "${CMAKE_CURRENT_SOURCE_DIR}"
       --output_dir "${CMAKE_CURRENT_BINARY_DIR}"
     WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}"
-    RESULTS_VARIABLE _gen_result)
+    RESULTS_VARIABLE _GEN_RESULT)
 
-  if(_gen_result)
+  if(_GEN_RESULT)
     message(SEND_ERROR "Error generating tests for ${CMAKE_CURRENT_SOURCE_DIR}")
   endif()
 endfunction()
@@ -46,27 +45,27 @@
     "GLOB"
     "LABELS"
     ${ARGN})
-  set(_glob "*.py")
+  set(_GLOB "*.py")
   if(ARG_GLOB)
-    set(_glob "${ARG_GLOB}")
+    set(_GLOB "${ARG_GLOB}")
   endif()
 
   file(GLOB
-    _found_test_files
+    _FOUND_TEST_FILES
     LIST_DIRECTORIES NO
     RELATIVE "${CMAKE_CURRENT_BINARY_DIR}/generated"
-    "${CMAKE_CURRENT_BINARY_DIR}/generated/${_glob}")
+    "${CMAKE_CURRENT_BINARY_DIR}/generated/${_GLOB}")
 
-  if(NOT _found_test_files)
+  if(NOT _FOUND_TEST_FILES)
     message(SEND_ERROR
-      "No generated tests (${_glob}) found under ${CMAKE_CURRENT_BINARY_DIR}/generated")
+      "No generated tests (${_GLOB}) found under ${CMAKE_CURRENT_BINARY_DIR}/generated")
   endif()
 
-  foreach(test_file ${_found_test_files})
+  foreach(_TEST_FILE ${_FOUND_TEST_FILES})
     iree_py_test(
-      NAME "generated/${test_file}"
+      NAME "generated/${_TEST_FILE}"
       GENERATED_IN_BINARY_DIR
-      SRCS "generated/${test_file}"
+      SRCS "generated/${_TEST_FILE}"
       LABELS
         generated
         ${ARG_LABELS}
diff --git a/build_tools/cmake/iree_trace_runner_test.cmake b/build_tools/cmake/iree_trace_runner_test.cmake
index 1c12fe2..e22122a 100644
--- a/build_tools/cmake/iree_trace_runner_test.cmake
+++ b/build_tools/cmake/iree_trace_runner_test.cmake
@@ -200,7 +200,7 @@
   list(APPEND _GENERATOR_STANDARD_FLAGS "--output_code=${_SRC}")
   list(APPEND _GENERATOR_STANDARD_FLAGS "--output_trace=${_TRACE}")
   list(APPEND _GENERATOR_STANDARD_FLAGS "--module_path=${_MODULE_FILE_NAME}")
-  if (_RULE_TARGET_CPU_FEATURES)
+  if(_RULE_TARGET_CPU_FEATURES)
     list(APPEND _GENERATOR_STANDARD_FLAGS "--requirements=${_RULE_TARGET_CPU_FEATURES}")
   endif()
   list(APPEND _GENERATOR_OUTPUT "${_TRACE}")
@@ -323,7 +323,7 @@
   foreach(_INDEX RANGE "${_MAX_INDEX}")
     list(GET _RULE_TARGET_BACKENDS ${_INDEX} _TARGET_BACKEND)
     list(GET _RULE_DRIVERS ${_INDEX} _DRIVER)
-    if (_TARGET_BACKEND STREQUAL "dylib-llvm-aot" AND _RULE_TARGET_CPU_FEATURES_VARIANTS)
+    if(_TARGET_BACKEND STREQUAL "dylib-llvm-aot" AND _RULE_TARGET_CPU_FEATURES_VARIANTS)
       set(_TARGET_CPU_FEATURES_VARIANTS "${_RULE_TARGET_CPU_FEATURES_VARIANTS}")
     else()
       set(_TARGET_CPU_FEATURES_VARIANTS "default")
@@ -331,7 +331,7 @@
     foreach(_TARGET_CPU_FEATURES_LIST_ELEM IN LISTS _TARGET_CPU_FEATURES_VARIANTS)
       process_target_cpu_features("${_TARGET_CPU_FEATURES_LIST_ELEM}" _ENABLED _TARGET_CPU_FEATURES _TARGET_CPU_FEATURES_SUFFIX _TARGET_PASS_OPTIONS)
       string(REPLACE "#pass_options_variant#" "${_TARGET_PASS_OPTIONS}" _PROCESSED_COMPILER_FLAGS "${_RULE_COMPILER_FLAGS}")
-      if (NOT _ENABLED)
+      if(NOT _ENABLED)
         # The current entry is disabled on the target CPU architecture.
         continue()
       endif()
diff --git a/build_tools/cmake/riscv.toolchain.cmake b/build_tools/cmake/riscv.toolchain.cmake
index 9e6a5fa..4034c52 100644
--- a/build_tools/cmake/riscv.toolchain.cmake
+++ b/build_tools/cmake/riscv.toolchain.cmake
@@ -4,7 +4,7 @@
 # See https://llvm.org/LICENSE.txt for license information.
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
-cmake_minimum_required (VERSION 3.13)
+cmake_minimum_required(VERSION 3.13)
 
 set(CMAKE_SYSTEM_PROCESSOR riscv)
 
diff --git a/build_tools/cmake/sanitizers.cmake b/build_tools/cmake/sanitizers.cmake
index 59388b3..95ce3bb 100644
--- a/build_tools/cmake/sanitizers.cmake
+++ b/build_tools/cmake/sanitizers.cmake
@@ -13,15 +13,15 @@
 # defined with the same sanitizer flags, including e.g. standard library
 # symbols that might be used by both IREE and non-IREE (e.g. LLVM) code.
 
-if(${IREE_ENABLE_ASAN})
+if(IREE_ENABLE_ASAN)
   string(APPEND CMAKE_CXX_FLAGS " -fsanitize=address")
   string(APPEND CMAKE_C_FLAGS " -fsanitize=address")
 endif()
-if(${IREE_ENABLE_MSAN})
+if(IREE_ENABLE_MSAN)
   string(APPEND CMAKE_CXX_FLAGS " -fsanitize=memory")
   string(APPEND CMAKE_C_FLAGS " -fsanitize=memory")
 endif()
-if(${IREE_ENABLE_TSAN})
+if(IREE_ENABLE_TSAN)
   string(APPEND CMAKE_CXX_FLAGS " -fsanitize=thread")
   string(APPEND CMAKE_C_FLAGS " -fsanitize=thread")
 endif()