diff --git a/llvm/test/tools/UpdateTestChecks/update_test_checks/Inputs/custom-tool.ll b/llvm/test/tools/UpdateTestChecks/update_test_checks/Inputs/custom-tool.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/UpdateTestChecks/update_test_checks/Inputs/custom-tool.ll
@@ -0,0 +1,6 @@
+; RUN: llvm-extract -S --func=foo %s | FileCheck --check-prefixes=CHECK %s
+
+define i32 @foo(i32 %x) {
+  %y = add i32 %x, 1
+  ret i32 %y
+}
diff --git a/llvm/test/tools/UpdateTestChecks/update_test_checks/Inputs/custom-tool.ll.expected b/llvm/test/tools/UpdateTestChecks/update_test_checks/Inputs/custom-tool.ll.expected
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/UpdateTestChecks/update_test_checks/Inputs/custom-tool.ll.expected
@@ -0,0 +1,11 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --tool llvm-extract
+; RUN: llvm-extract -S --func=foo %s | FileCheck --check-prefixes=CHECK %s
+
+define i32 @foo(i32 %x) {
+; CHECK-LABEL: @foo(
+; CHECK-NEXT:    [[Y:%.*]] = add i32 [[X:%.*]], 1
+; CHECK-NEXT:    ret i32 [[Y]]
+;
+  %y = add i32 %x, 1
+  ret i32 %y
+}
diff --git a/llvm/test/tools/UpdateTestChecks/update_test_checks/custom-tool.test b/llvm/test/tools/UpdateTestChecks/update_test_checks/custom-tool.test
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/UpdateTestChecks/update_test_checks/custom-tool.test
@@ -0,0 +1,6 @@
+# RUN: cp -f %S/Inputs/custom-tool.ll %t.ll && %update_test_checks %t.ll --tool=llvm-extract --tool-binary=llvm-extract
+# RUN: diff -u %t.ll %S/Inputs/custom-tool.ll.expected
+
+## Check that running the script again does not change the result.
+# RUN: %update_test_checks %t.ll --tool=grep --tool-binary=grep
+# RUN: diff -u %t.ll %S/Inputs/custom-tool.ll.expected
diff --git a/llvm/utils/UpdateTestChecks/common.py b/llvm/utils/UpdateTestChecks/common.py
--- a/llvm/utils/UpdateTestChecks/common.py
+++ b/llvm/utils/UpdateTestChecks/common.py
@@ -1154,8 +1154,8 @@
     if not hasattr(args, action.dest):
       continue  # Ignore options such as --help that aren't included in args
     # Ignore parameters such as paths to the binary or the list of tests
-    if action.dest in ('tests', 'update_only', 'opt_binary', 'llc_binary',
-                       'clang', 'opt', 'llvm_bin', 'verbose'):
+    if action.dest in ('tests', 'update_only', 'tool_binary', 'opt_binary',
+                       'llc_binary', 'clang', 'opt', 'llvm_bin', 'verbose'):
       continue
     value = getattr(args, action.dest)
     if action.const is not None:  # action stores a constant (usually True/False)
diff --git a/llvm/utils/update_test_checks.py b/llvm/utils/update_test_checks.py
--- a/llvm/utils/update_test_checks.py
+++ b/llvm/utils/update_test_checks.py
@@ -37,8 +37,10 @@
 def main():
   from argparse import RawTextHelpFormatter
   parser = argparse.ArgumentParser(description=__doc__, formatter_class=RawTextHelpFormatter)
-  parser.add_argument('--opt-binary', default='opt',
-                      help='The opt binary used to generate the test case')
+  parser.add_argument('--tool', default='opt',
+                      help='The name of the tool used to generate the test case (defaults to "opt")')
+  parser.add_argument('--tool-binary', '--opt-binary',
+                      help='The tool binary used to generate the test case')
   parser.add_argument(
       '--function', help='The function in the test file to update')
   parser.add_argument('-p', '--preserve-names', action='store_true',
@@ -55,11 +57,13 @@
   initial_args = common.parse_commandline_args(parser)
 
   script_name = os.path.basename(__file__)
-  opt_basename = os.path.basename(initial_args.opt_binary)
-  if not re.match(r'^opt(-\d+)?(\.exe)?$', opt_basename):
-    common.error('Unexpected opt name: ' + opt_basename)
-    sys.exit(1)
-  opt_basename = 'opt'
+
+  if initial_args.tool_binary:
+    tool_basename = os.path.basename(initial_args.tool_binary)
+    if not re.match(r'^%s(-\d+)?(\.exe)?$' % (initial_args.tool), tool_basename):
+      common.error('Unexpected tool name: ' + tool_basename)
+      sys.exit(1)
+  tool_basename = initial_args.tool
 
   for ti in common.itertests(initial_args.tests, parser,
                              script_name='utils/' + script_name):
@@ -83,15 +87,15 @@
       tool_cmd = commands[-2]
       filecheck_cmd = commands[-1]
       common.verify_filecheck_prefixes(filecheck_cmd)
-      if not tool_cmd.startswith(opt_basename + ' '):
-        common.warn('Skipping non-%s RUN line: %s' % (opt_basename, l))
+      if not tool_cmd.startswith(tool_basename + ' '):
+        common.warn('Skipping non-%s RUN line: %s' % (tool_basename, l))
         continue
 
       if not filecheck_cmd.startswith('FileCheck '):
         common.warn('Skipping non-FileChecked RUN line: ' + l)
         continue
 
-      tool_cmd_args = tool_cmd[len(opt_basename):].strip()
+      tool_cmd_args = tool_cmd[len(tool_basename):].strip()
       tool_cmd_args = tool_cmd_args.replace('< %s', '').replace('%s', '').strip()
 
       check_prefixes = [item for m in
@@ -111,11 +115,15 @@
       scrubber_args=[],
       path=ti.path)
 
+    tool_binary = ti.args.tool_binary
+    if not tool_binary:
+      tool_binary = tool_basename
+
     for prefixes, opt_args, preprocess_cmd in prefix_list:
-      common.debug('Extracted opt cmd: ' + opt_basename + ' ' + opt_args)
+      common.debug('Extracted opt cmd: ' + tool_basename + ' ' + opt_args)
       common.debug('Extracted FileCheck prefixes: ' + str(prefixes))
 
-      raw_tool_output = common.invoke_tool(ti.args.opt_binary, opt_args,
+      raw_tool_output = common.invoke_tool(tool_binary, opt_args,
                                            ti.path, preprocess_cmd=preprocess_cmd,
                                            verbose=ti.args.verbose)
       builder.process_run_line(common.OPT_FUNCTION_RE, common.scrub_body,