diff --git a/llvm/test/tools/llvm-reduce/custom-delta-passes.ll b/llvm/test/tools/llvm-reduce/custom-delta-passes.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/llvm-reduce/custom-delta-passes.ll
@@ -0,0 +1,24 @@
+; RUN: llvm-reduce --delta-passes=module-inline-asm --test FileCheck --test-arg --check-prefixes=CHECK-INTERESTINGNESS --test-arg %s --test-arg --input-file %s -o %t
+; RUN: FileCheck --check-prefix=CHECK-NOCHANGE %s < %t
+; RUN: llvm-reduce --delta-passes=function-bodies --test FileCheck --test-arg --check-prefixes=CHECK-INTERESTINGNESS --test-arg %s --test-arg --input-file %s -o %t
+; RUN: FileCheck --check-prefix=CHECK-CHANGE %s < %t
+; RUN: llvm-reduce --delta-passes=function-bodies,module-inline-asm --test FileCheck --test-arg --check-prefixes=CHECK-INTERESTINGNESS --test-arg %s --test-arg --input-file %s -o %t
+; RUN: FileCheck --check-prefix=CHECK-CHANGE %s < %t
+
+; RUN: not llvm-reduce --delta-passes=foo --test FileCheck --test-arg --check-prefixes=CHECK-INTERESTINGNESS --test-arg %s --test-arg --input-file %s -o %t 2>&1 | FileCheck %s --check-prefix=ERROR
+; RUN: not llvm-reduce --delta-passes='function-bodies;module-inline-asm' --test FileCheck --test-arg --check-prefixes=CHECK-INTERESTINGNESS --test-arg %s --test-arg --input-file %s -o %t 2>&1 | FileCheck %s --check-prefix=ERROR
+
+; RUN: llvm-reduce --print-delta-passes --test FileCheck %s 2>&1 | FileCheck %s --check-prefix=PRINT
+
+; CHECK-INTERESTINGNESS: @f
+
+; CHECK-NOCHANGE: define {{.*}} @f
+; CHECK-CHANGE: declare {{.*}} @f
+
+; ERROR: unknown
+
+; PRINT: function-bodies
+
+define void @f() {
+  ret void
+}
diff --git a/llvm/tools/llvm-reduce/DeltaManager.h b/llvm/tools/llvm-reduce/DeltaManager.h
--- a/llvm/tools/llvm-reduce/DeltaManager.h
+++ b/llvm/tools/llvm-reduce/DeltaManager.h
@@ -14,9 +14,11 @@
 #ifndef LLVM_TOOLS_LLVM_REDUCE_DELTAMANAGER_H
 #define LLVM_TOOLS_LLVM_REDUCE_DELTAMANAGER_H
 
-#include "TestRunner.h"
-
 namespace llvm {
+class raw_ostream;
+class TestRunner;
+
+void printDeltaPasses(raw_ostream &OS);
 void runDeltaPasses(TestRunner &Tester);
 } // namespace llvm
 
diff --git a/llvm/tools/llvm-reduce/DeltaManager.cpp b/llvm/tools/llvm-reduce/DeltaManager.cpp
--- a/llvm/tools/llvm-reduce/DeltaManager.cpp
+++ b/llvm/tools/llvm-reduce/DeltaManager.cpp
@@ -28,25 +28,65 @@
 #include "deltas/ReduceModuleInlineAsm.h"
 #include "deltas/ReduceOperandBundles.h"
 #include "deltas/ReduceSpecialGlobals.h"
+#include "llvm/Support/CommandLine.h"
 
-namespace llvm {
-
-// TODO: Add CLI option to run only specified Passes (for unit tests)
-void runDeltaPasses(TestRunner &Tester) {
-  reduceSpecialGlobalsDeltaPass(Tester);
-  reduceAliasesDeltaPass(Tester);
-  reduceFunctionBodiesDeltaPass(Tester);
-  reduceFunctionsDeltaPass(Tester);
-  reduceBasicBlocksDeltaPass(Tester);
-  reduceGlobalValuesDeltaPass(Tester);
-  reduceGlobalsInitializersDeltaPass(Tester);
-  reduceGlobalsDeltaPass(Tester);
-  reduceMetadataDeltaPass(Tester);
-  reduceArgumentsDeltaPass(Tester);
-  reduceInstructionsDeltaPass(Tester);
-  reduceOperandBundesDeltaPass(Tester);
-  reduceAttributesDeltaPass(Tester);
-  reduceModuleInlineAsmDeltaPass(Tester);
-  // TODO: Implement the remaining Delta Passes
+using namespace llvm;
+
+static cl::opt<std::string>
+    DeltaPasses("delta-passes",
+                cl::desc("Delta passes to run, separated by commas. By "
+                         "default, run all delta passes."));
+
+#define DELTA_PASSES                                                           \
+  DELTA_PASS("special-globals", reduceSpecialGlobalsDeltaPass)                 \
+  DELTA_PASS("aliases", reduceAliasesDeltaPass)                                \
+  DELTA_PASS("function-bodies", reduceFunctionBodiesDeltaPass)                 \
+  DELTA_PASS("functions", reduceFunctionsDeltaPass)                            \
+  DELTA_PASS("basic-blocks", reduceBasicBlocksDeltaPass)                       \
+  DELTA_PASS("global-values", reduceGlobalValuesDeltaPass)                     \
+  DELTA_PASS("global-initializers", reduceGlobalsInitializersDeltaPass)        \
+  DELTA_PASS("global-variables", reduceGlobalsDeltaPass)                       \
+  DELTA_PASS("metadata", reduceMetadataDeltaPass)                              \
+  DELTA_PASS("arguments", reduceArgumentsDeltaPass)                            \
+  DELTA_PASS("instructions", reduceInstructionsDeltaPass)                      \
+  DELTA_PASS("operand-bundles", reduceOperandBundesDeltaPass)                  \
+  DELTA_PASS("attributes", reduceAttributesDeltaPass)                          \
+  DELTA_PASS("module-inline-asm", reduceModuleInlineAsmDeltaPass)
+
+static void runAllDeltaPasses(TestRunner &Tester) {
+#define DELTA_PASS(NAME, FUNC) FUNC(Tester);
+  DELTA_PASSES
+#undef DELTA_PASS
+}
+
+static void runDeltaPassName(TestRunner &Tester, StringRef PassName) {
+#define DELTA_PASS(NAME, FUNC)                                                 \
+  if (PassName == NAME) {                                                      \
+    FUNC(Tester);                                                              \
+    return;                                                                    \
+  }
+  DELTA_PASSES
+#undef DELTA_PASS
+  errs() << "unknown pass \"" << PassName << "\"";
+  exit(1);
+}
+
+void llvm::printDeltaPasses(raw_ostream &OS) {
+  OS << "Delta passes (pass to `--delta-passes=` as a comma separated list):\n";
+#define DELTA_PASS(NAME, FUNC) OS << "  " << NAME << "\n";
+  DELTA_PASSES
+#undef DELTA_PASS
+}
+
+void llvm::runDeltaPasses(TestRunner &Tester) {
+  if (DeltaPasses.empty()) {
+    runAllDeltaPasses(Tester);
+  } else {
+    StringRef Passes = DeltaPasses;
+    while (!Passes.empty()) {
+      auto Split = Passes.split(",");
+      runDeltaPassName(Tester, Split.first);
+      Passes = Split.second;
+    }
+  }
 }
-} // namespace llvm
diff --git a/llvm/tools/llvm-reduce/llvm-reduce.cpp b/llvm/tools/llvm-reduce/llvm-reduce.cpp
--- a/llvm/tools/llvm-reduce/llvm-reduce.cpp
+++ b/llvm/tools/llvm-reduce/llvm-reduce.cpp
@@ -15,6 +15,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "DeltaManager.h"
+#include "TestRunner.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Verifier.h"
@@ -35,6 +36,11 @@
 static cl::opt<bool> Version("v", cl::desc("Alias for -version"), cl::Hidden,
                              cl::cat(Options));
 
+static cl::opt<bool>
+    PrintDeltaPasses("print-delta-passes",
+                     cl::desc("Print list of delta passes, passable to "
+                              "--delta-passes as a comma separated list"));
+
 static cl::opt<std::string> InputFilename(cl::Positional, cl::Required,
                                           cl::desc("<input llvm ll/bc file>"),
                                           cl::cat(Options));
@@ -101,6 +107,11 @@
 
   cl::ParseCommandLineOptions(Argc, Argv, "LLVM automatic testcase reducer.\n");
 
+  if (PrintDeltaPasses) {
+    printDeltaPasses(errs());
+    return 0;
+  }
+
   LLVMContext Context;
   std::unique_ptr<Module> OriginalProgram =
       parseInputFile(InputFilename, Context);