diff --git a/libcxx/utils/libcxx/test/config.py b/libcxx/utils/libcxx/test/config.py
--- a/libcxx/utils/libcxx/test/config.py
+++ b/libcxx/utils/libcxx/test/config.py
@@ -621,6 +621,7 @@
         env_vars = ' '.join('%s=%s' % (k, pipes.quote(v)) for (k, v) in self.exec_env.items())
         exec_args = [
             '--execdir %T',
+            '--test-executable %t.exe',
             '--codesign_identity "{}"'.format(codesign_ident),
             '--env {}'.format(env_vars)
         ]
diff --git a/libcxx/utils/run.py b/libcxx/utils/run.py
--- a/libcxx/utils/run.py
+++ b/libcxx/utils/run.py
@@ -14,6 +14,7 @@
 """
 
 import argparse
+import os
 import subprocess
 import sys
 
@@ -22,18 +23,33 @@
     parser = argparse.ArgumentParser()
     parser.add_argument('--execdir', type=str, required=True)
     parser.add_argument('--codesign_identity', type=str, required=False, default=None)
+    parser.add_argument('--test-executable', type=str, required=False, default=None,
+                        help='The name of an executable generated by a test \
+                              file. Specifying it allows us to do custom \
+                              processing like codesigning test-executables. \
+                              It\'s also possible for there \
+                              to be no such executable, for example in \
+                              the case of a .sh.cpp test.')
     parser.add_argument('--env', type=str, nargs='*', required=False, default=dict())
     parser.add_argument("command", nargs=argparse.ONE_OR_MORE)
     args = parser.parse_args()
     commandLine = args.command
 
+    def isTestExe(exe):
+        if not exe or not args.test_executable:
+            return False
+        try:
+            return os.path.samefile(exe, args.test_executable)
+        except FileNotFoundError:
+            return False
+
     # Do any necessary codesigning.
     if args.codesign_identity:
-        exe = commandLine[0]
-        rc = subprocess.call(['xcrun', 'codesign', '-f', '-s', args.codesign_identity, exe], env={})
-        if rc != 0:
-            sys.stderr.write('Failed to codesign: ' + exe)
-            return rc
+        for exe in filter(isTestExe, commandLine):
+            rc = subprocess.call(['xcrun', 'codesign', '-f', '-s', args.codesign_identity, exe], env={})
+            if rc != 0:
+                sys.stderr.write('Failed to codesign: ' + exe)
+                return rc
 
     # Extract environment variables into a dictionary
     env = {k : v  for (k, v) in map(lambda s: s.split('=', 1), args.env)}
diff --git a/libcxx/utils/ssh.py b/libcxx/utils/ssh.py
--- a/libcxx/utils/ssh.py
+++ b/libcxx/utils/ssh.py
@@ -44,6 +44,14 @@
     parser.add_argument('--extra-ssh-args', type=str, required=False)
     parser.add_argument('--extra-scp-args', type=str, required=False)
     parser.add_argument('--codesign_identity', type=str, required=False, default=None)
+    parser.add_argument('--test-executable', type=str, required=False, default=None,
+                        help='The name of an executable generated by a test \
+                              file. Specifying it allows us to do custom \
+                              processing like codesigning test-executables \
+                              and changing their path when running on \
+                              the remote host. It\'s also possible for there \
+                              to be no such executable, for example in \
+                              the case of a .sh.cpp test.')
     parser.add_argument('--env', type=str, nargs='*', required=False, default=dict())
     parser.add_argument("command", nargs=argparse.ONE_OR_MORE)
     args = parser.parse_args()
@@ -53,14 +61,14 @@
     # That is effectively the value of %T on the remote host.
     tmp = subprocess.check_output(ssh(args, 'mktemp -d /tmp/libcxx.XXXXXXXXXX'), universal_newlines=True).strip()
 
-    # HACK:
-    # If an argument is a file that ends in `.tmp.exe`, assume it is the name
-    # of an executable generated by a test file. We call these test-executables
-    # below. This allows us to do custom processing like codesigning test-executables
-    # and changing their path when running on the remote host. It's also possible
-    # for there to be no such executable, for example in the case of a .sh.cpp
-    # test.
-    isTestExe = lambda exe: exe.endswith('.tmp.exe') and os.path.exists(exe)
+    def isTestExe(exe):
+        if not exe or not args.test_executable:
+            return False
+        try:
+            return os.path.samefile(exe, args.test_executable)
+        except FileNotFoundError:
+            return False
+
     pathOnRemote = lambda file: posixpath.join(tmp, os.path.basename(file))
 
     try: