diff --git a/cmake/Modules/AddCompilerRT.cmake b/cmake/Modules/AddCompilerRT.cmake
index 3c1e1c1..a84aba4 100644
--- a/cmake/Modules/AddCompilerRT.cmake
+++ b/cmake/Modules/AddCompilerRT.cmake
@@ -203,6 +203,14 @@
         set_target_properties(${libname} PROPERTIES IMPORT_PREFIX "")
         set_target_properties(${libname} PROPERTIES IMPORT_SUFFIX ".lib")
       endif()
+      if(APPLE)
+        # Ad-hoc sign the dylibs
+        add_custom_command(TARGET ${libname}
+          POST_BUILD  
+          COMMAND codesign --sign - $<TARGET_FILE:${libname}>
+          WORKING_DIRECTORY ${COMPILER_RT_LIBRARY_OUTPUT_DIR}
+        )
+      endif()
     endif()
     install(TARGETS ${libname}
       ARCHIVE DESTINATION ${COMPILER_RT_LIBRARY_INSTALL_DIR}
diff --git a/test/asan/CMakeLists.txt b/test/asan/CMakeLists.txt
index 637c5b8..a766f54 100644
--- a/test/asan/CMakeLists.txt
+++ b/test/asan/CMakeLists.txt
@@ -41,6 +41,12 @@
   else()
     set(ASAN_TEST_TARGET_ARCH ${arch})
   endif()
+
+  set(ASAN_TEST_IOS "0")
+  pythonize_bool(ASAN_TEST_IOS)
+  set(ASAN_TEST_IOSSIM "0")
+  pythonize_bool(ASAN_TEST_IOSSIM)
+
   string(TOLOWER "-${arch}-${OS_NAME}" ASAN_TEST_CONFIG_SUFFIX)
   get_bits_for_arch(${arch} ASAN_TEST_BITS)
   get_test_cc_for_arch(${arch} ASAN_TEST_TARGET_CC ASAN_TEST_TARGET_CFLAGS)
@@ -69,6 +75,49 @@
   endif()
 endforeach()
 
+# iOS and iOS simulator test suites
+# These are not added into "check-all", in order to run these tests, you have to
+# manually call (from the build directory).  They also require that an extra env
+# variable to select which iOS device or simulator to use, e.g.:
+# $ SANITIZER_IOSSIM_TEST_DEVICE_IDENTIFIER=BBE44C1C-8AAA-4000-8D06-91C89ED58172
+# $ ./bin/llvm-lit ./projects/compiler-rt/test/asan/IOSSimI386Config
+if(APPLE)
+  set(ASAN_TEST_TARGET_CC ${COMPILER_RT_TEST_COMPILER})
+  set(ASAN_TEST_IOS "1")
+  pythonize_bool(ASAN_TEST_IOS)
+  set(ASAN_TEST_DYNAMIC True)
+
+  foreach(arch ${DARWIN_iossim_ARCHS})
+    set(ASAN_TEST_IOSSIM "1")
+    pythonize_bool(ASAN_TEST_IOSSIM)
+    set(ASAN_TEST_TARGET_ARCH ${arch})
+    set(ASAN_TEST_TARGET_CFLAGS "-arch ${arch} -isysroot ${DARWIN_iossim_SYSROOT} ${COMPILER_RT_TEST_COMPILER_CFLAGS}")
+    set(ASAN_TEST_CONFIG_SUFFIX "-${arch}-iossim")
+    get_bits_for_arch(${arch} ASAN_TEST_BITS)
+    string(TOUPPER ${arch} ARCH_UPPER_CASE)
+    set(CONFIG_NAME "IOSSim${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
+      )
+  endforeach()
+
+  foreach (arch ${DARWIN_ios_ARCHS})
+    set(ASAN_TEST_IOSSIM "0")
+    pythonize_bool(ASAN_TEST_IOSSIM)
+    set(ASAN_TEST_TARGET_ARCH ${arch})
+    set(ASAN_TEST_TARGET_CFLAGS "-arch ${arch} -isysroot ${DARWIN_ios_SYSROOT} ${COMPILER_RT_TEST_COMPILER_CFLAGS}")
+    set(ASAN_TEST_CONFIG_SUFFIX "-${arch}-ios")
+    get_bits_for_arch(${arch} ASAN_TEST_BITS)
+    string(TOUPPER ${arch} ARCH_UPPER_CASE)
+    set(CONFIG_NAME "IOS${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
+      )
+  endforeach()
+endif()
+
 # Add unit tests.
 if(COMPILER_RT_INCLUDE_TESTS)
   set(ASAN_TEST_DYNAMIC False)
diff --git a/test/asan/lit.site.cfg.in b/test/asan/lit.site.cfg.in
index 1b6fed2..100592d 100644
--- a/test/asan/lit.site.cfg.in
+++ b/test/asan/lit.site.cfg.in
@@ -7,6 +7,8 @@
 config.clang = "@ASAN_TEST_TARGET_CC@"
 config.bits = "@ASAN_TEST_BITS@"
 config.android = "@ANDROID@"
+config.ios = @ASAN_TEST_IOS_PYBOOL@
+config.iossim = @ASAN_TEST_IOSSIM_PYBOOL@
 config.asan_dynamic = @ASAN_TEST_DYNAMIC@
 config.target_arch = "@ASAN_TEST_TARGET_ARCH@"
 
diff --git a/test/lit.common.cfg b/test/lit.common.cfg
index e90d738..8d0c740 100644
--- a/test/lit.common.cfg
+++ b/test/lit.common.cfg
@@ -86,7 +86,16 @@
      instead define '%clangXXX' substitution in lit config. ***\n\n""") )
 
 # Allow tests to be executed on a simulator or remotely.
-config.substitutions.append( ('%run', config.emulator) )
+if config.emulator:
+  config.substitutions.append( ('%run', config.emulator) )
+elif config.ios:
+  device_id_env = "SANITIZER_IOSSIM_TEST_DEVICE_IDENTIFIER" if config.iossim else "SANITIZER_IOS_TEST_DEVICE_IDENTIFIER"
+  if device_id_env in os.environ: config.environment[device_id_env] = os.environ[device_id_env]
+  ios_commands_dir = os.path.join(config.compiler_rt_src_root, "test", "sanitizer_common", "ios_commands")
+  run_wrapper = os.path.join(ios_commands_dir, "iossim_run.py" if config.iossim else "ios_run.py")
+  config.substitutions.append(('%run', run_wrapper))
+else:
+  config.substitutions.append( ('%run', "") )
 
 # Define CHECK-%os to check for OS-dependent output.
 config.substitutions.append( ('CHECK-%os', ("CHECK-" + config.host_os)))
diff --git a/test/lit.common.configured.in b/test/lit.common.configured.in
index 862d06b..685aa01 100644
--- a/test/lit.common.configured.in
+++ b/test/lit.common.configured.in
@@ -25,6 +25,8 @@
 set_default("compiler_rt_debug", @COMPILER_RT_DEBUG_PYBOOL@)
 set_default("compiler_rt_libdir", "@COMPILER_RT_LIBRARY_OUTPUT_DIR@")
 set_default("emulator", "@COMPILER_RT_EMULATOR@")
+set_default("ios", False)
+set_default("iossim", False)
 set_default("sanitizer_can_use_cxxabi", @SANITIZER_CAN_USE_CXXABI_PYBOOL@)
 set_default("has_lld", @COMPILER_RT_HAS_LLD_SOURCES_PYBOOL@)
 set_default("can_symbolize", @CAN_SYMBOLIZE@)
diff --git a/test/sanitizer_common/ios_commands/iossim_env.py b/test/sanitizer_common/ios_commands/iossim_env.py
new file mode 100644
index 0000000..28f6269
--- /dev/null
+++ b/test/sanitizer_common/ios_commands/iossim_env.py
@@ -0,0 +1,17 @@
+#!/usr/bin/python
+
+import os, sys, subprocess
+
+
+idx = 1
+for arg in sys.argv[1:]:
+  if not "=" in arg:
+    break
+  idx += 1
+  (argname, argval) = arg.split("=")
+  os.environ["SIMCTL_CHILD_" + argname] = argval
+
+exitcode = subprocess.call(sys.argv[idx:])
+if exitcode > 125:
+  exitcode = 126
+sys.exit(exitcode)
diff --git a/test/sanitizer_common/ios_commands/iossim_run.py b/test/sanitizer_common/ios_commands/iossim_run.py
new file mode 100644
index 0000000..732880f
--- /dev/null
+++ b/test/sanitizer_common/ios_commands/iossim_run.py
@@ -0,0 +1,17 @@
+#!/usr/bin/python
+
+import os, sys, subprocess
+
+
+if not "SANITIZER_IOSSIM_TEST_DEVICE_IDENTIFIER" in os.environ:
+  raise EnvironmentError("Specify SANITIZER_IOSSIM_TEST_DEVICE_IDENTIFIER to select which simulator to use.")
+
+device_id = os.environ["SANITIZER_IOSSIM_TEST_DEVICE_IDENTIFIER"]
+
+if "ASAN_OPTIONS" in os.environ:
+    os.environ["SIMCTL_CHILD_ASAN_OPTIONS"] = os.environ["ASAN_OPTIONS"]
+
+exitcode = subprocess.call(["xcrun", "simctl", "spawn", device_id] + sys.argv[1:])
+if exitcode > 125:
+  exitcode = 126
+sys.exit(exitcode)