Index: utils/lit/lit/main.py
===================================================================
--- utils/lit/lit/main.py
+++ utils/lit/lit/main.py
@@ -321,6 +321,9 @@
     debug_group.add_argument("--show-tests", dest="showTests",
                       help="Show all discovered tests",
                       action="store_true", default=False)
+    debug_group.add_argument("--show-substitutions", dest="showSubstitutions",
+                      help="Show all substitutions (implies --show-suites)",
+                      action="store_true", default=False)
     debug_group.add_argument("--single-process", dest="singleProcess",
                       help="Don't run tests in parallel.  Intended for debugging "
                       "single test failures",
@@ -345,6 +348,9 @@
     if opts.echoAllCommands:
         opts.showOutput = True
 
+    if opts.showSubstitutions:
+        opts.showSuites = True
+
     inputs = args
 
     # Create the user defined parameters.
@@ -421,6 +427,14 @@
                 if ts.config.available_features:
                     print('    Available Features : %s' % ' '.join(
                         sorted(ts.config.available_features)))
+                if opts.showSubstitutions and ts.config.substitutions:
+                    print('    Substitutions')
+                    for (pattern, replacement) in ts.config.substitutions:
+                        if re.match(r'[\'"]|.*\s', pattern):
+                            pattern = repr(pattern)
+                        if re.match(r'[\'"]|.*\s|$', replacement):
+                            replacement = repr(replacement)
+                        print('        %s = %s' %(pattern, replacement))
 
         # Show the tests, if requested.
         if opts.showTests:
Index: utils/lit/tests/Inputs/show-substitutions/lit.cfg
===================================================================
--- /dev/null
+++ utils/lit/tests/Inputs/show-substitutions/lit.cfg
@@ -0,0 +1,13 @@
+import lit.formats
+
+config.name = 'shtest-shell'
+config.suffixes = ['.txt']
+config.test_format = lit.formats.ShTest()
+config.test_source_root = None
+config.test_exec_root = None
+
+config.substitutions = [('%foo', 'foo'),
+                        ('%foo', ''),
+                        (r'\|%lli\b(?!(\.))', '/bin/lli'),
+                        (r'\| not', '/bin/not '),
+                        ("'foo'", '"foo"')]
Index: utils/lit/tests/Inputs/show-substitutions/test.txt
===================================================================
--- /dev/null
+++ utils/lit/tests/Inputs/show-substitutions/test.txt
@@ -0,0 +1 @@
+# RUN: true
Index: utils/lit/tests/show-substitutions.py
===================================================================
--- /dev/null
+++ utils/lit/tests/show-substitutions.py
@@ -0,0 +1,8 @@
+# RUN: %{lit} --show-substitutions %{inputs}/show-substitutions | FileCheck %s
+
+# CHECK: Substitutions
+# CHECK-NEXT: %foo = foo
+# CHECK-NEXT: %foo = ''
+# CHECK-NEXT: \|%lli\b(?!(\.)) = /bin/lli
+# CHECK-NEXT: '\\| not' = '/bin/not '
+# CHECK-NEXT: "'foo'" = '"foo"'