Index: test/msan/CMakeLists.txt
===================================================================
--- test/msan/CMakeLists.txt
+++ test/msan/CMakeLists.txt
@@ -1,8 +1,32 @@
 set(MSAN_LIT_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR})
 
-configure_lit_site_cfg(
-  ${CMAKE_CURRENT_SOURCE_DIR}/lit.site.cfg.in
-  ${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg)
+set(MSAN_TESTSUITES)
+
+set(MSAN_TEST_ARCH ${MSAN_SUPPORTED_ARCH})
+if(APPLE)
+  darwin_filter_host_archs(MSAN_SUPPORTED_ARCH MSAN_TEST_ARCH)
+endif()
+
+foreach(arch ${MSAN_TEST_ARCH})
+  string(TOLOWER "-${arch}" MSAN_TEST_CONFIG_SUFFIX)
+  if(ANDROID OR ${arch} MATCHES "arm|aarch64")
+    # This is only true if we are cross-compiling.
+    # Build all tests with host compiler and use host tools.
+    set(MSAN_TEST_TARGET_CC ${COMPILER_RT_TEST_COMPILER})
+    set(MSAN_TEST_TARGET_CFLAGS ${COMPILER_RT_TEST_COMPILER_CFLAGS})
+  else()
+    get_target_flags_for_arch(${arch} MSAN_TEST_TARGET_CFLAGS)
+    string(REPLACE ";" " " MSAN_TEST_TARGET_CFLAGS "${MSAN_TEST_TARGET_CFLAGS}")
+  endif()
+
+  string(TOUPPER ${arch} ARCH_UPPER_CASE)
+  set(CONFIG_NAME ${ARCH_UPPER_CASE}Config)
+
+  configure_lit_site_cfg(
+    ${CMAKE_CURRENT_SOURCE_DIR}/lit.site.cfg.in
+    ${CMAKE_CURRENT_BINARY_DIR}/${CONFIG_NAME}/lit.site.cfg)
+  list(APPEND MSAN_TESTSUITES ${CMAKE_CURRENT_BINARY_DIR}/${CONFIG_NAME})
+endforeach()
 
 set(MSAN_TEST_DEPS ${SANITIZER_COMMON_LIT_TEST_DEPS})
 if(NOT COMPILER_RT_STANDALONE_BUILD)
@@ -17,7 +41,7 @@
 endif()
 
 add_lit_testsuite(check-msan "Running the MemorySanitizer tests"
-  ${CMAKE_CURRENT_BINARY_DIR}
+  ${MSAN_TESTSUITES}
   DEPENDS ${MSAN_TEST_DEPS}
   )
 set_target_properties(check-msan PROPERTIES FOLDER "MSan tests")
Index: test/msan/lit.cfg
===================================================================
--- test/msan/lit.cfg
+++ test/msan/lit.cfg
@@ -3,17 +3,18 @@
 import os
 
 # Setup config name.
-config.name = 'MemorySanitizer'
+config.name = 'MemorySanitizer' + config.name_suffix
 
 # Setup source root.
 config.test_source_root = os.path.dirname(__file__)
 
 # Setup default compiler flags used with -fsanitize=memory option.
-clang_msan_cflags = ["-fsanitize=memory",
-                     "-mno-omit-leaf-frame-pointer",
-                     "-fno-omit-frame-pointer",
-                     "-fno-optimize-sibling-calls",
-                     "-m64"] + config.debug_info_flags
+clang_msan_cflags = (["-fsanitize=memory",
+                      "-mno-omit-leaf-frame-pointer",
+                      "-fno-omit-frame-pointer",
+                      "-fno-optimize-sibling-calls"] +
+                      [config.target_cflags] +
+                      config.debug_info_flags)
 # Some Msan tests leverage backtrace() which requires libexecinfo on FreeBSD.
 if config.host_os == 'FreeBSD':
   clang_msan_cflags += ["-lexecinfo"]
Index: test/msan/lit.site.cfg.in
===================================================================
--- test/msan/lit.site.cfg.in
+++ test/msan/lit.site.cfg.in
@@ -1,5 +1,11 @@
+## Autogenerated by LLVM/Clang configuration.
+# Do not edit!
+
 # Load common config for all compiler-rt lit tests.
 lit_config.load_config(config, "@COMPILER_RT_BINARY_DIR@/test/lit.common.configured")
 
+# Tool-specific config options.
+config.name_suffix = "@MSAN_TEST_CONFIG_SUFFIX@"
+config.target_cflags = "@MSAN_TEST_TARGET_CFLAGS@"
 # Load tool-specific config that would do the real work.
 lit_config.load_config(config, "@MSAN_LIT_SOURCE_DIR@/lit.cfg")