diff --git a/llvm/lib/Passes/PassRegistry.def b/llvm/lib/Passes/PassRegistry.def
index d2906eef8dd9d..2241a383ebce1 100644
--- a/llvm/lib/Passes/PassRegistry.def
+++ b/llvm/lib/Passes/PassRegistry.def
@@ -268,19 +268,19 @@ MODULE_PASS_WITH_PARAMS(
       setupOptionsForPipelineAlias(PTO, L);
       return buildPerModuleDefaultPipeline(L);
     },
-    parseOptLevelParam, "O0;O1;O2;O3;Os;Oz")
+    parseOptLevelParam, "O0;O1;O2;O3")
 MODULE_PASS_WITH_PARAMS(
     "thinlto-pre-link", "", [&](OptimizationLevel L) {
       setupOptionsForPipelineAlias(PTO, L);
       return buildThinLTOPreLinkDefaultPipeline(L);
     },
-    parseOptLevelParam, "O0;O1;O2;O3;Os;Oz")
+    parseOptLevelParam, "O0;O1;O2;O3")
 MODULE_PASS_WITH_PARAMS(
     "thinlto", "", [&](OptimizationLevel L) {
       setupOptionsForPipelineAlias(PTO, L);
       return buildThinLTODefaultPipeline(L, nullptr);
     },
-    parseOptLevelParam, "O0;O1;O2;O3;Os;Oz")
+    parseOptLevelParam, "O0;O1;O2;O3")
 MODULE_PASS_WITH_PARAMS(
     "lto-pre-link", "", [&](OptimizationLevel L) {
       setupOptionsForPipelineAlias(PTO, L);
@@ -292,20 +292,20 @@ MODULE_PASS_WITH_PARAMS(
       }
       return buildLTOPreLinkDefaultPipeline(L);
     },
-    parseOptLevelParam, "O0;O1;O2;O3;Os;Oz")
+    parseOptLevelParam, "O0;O1;O2;O3")
 MODULE_PASS_WITH_PARAMS(
     "lto", "", [&](OptimizationLevel L) {
       setupOptionsForPipelineAlias(PTO, L);
       return buildLTODefaultPipeline(L, nullptr);
     },
-    parseOptLevelParam, "O0;O1;O2;O3;Os;Oz")
+    parseOptLevelParam, "O0;O1;O2;O3")
 MODULE_PASS_WITH_PARAMS(
     "fatlto-pre-link", "", [&](FatLTOOptions Opts) {
       setupOptionsForPipelineAlias(PTO, Opts.OptLevel);
       return buildFatLTODefaultPipeline(Opts.OptLevel, Opts.ThinLTO,
                                         Opts.EmitSummary);
     },
-    parseFatLTOOptions, "O0;O1;O2;O3;Os;Oz;thinlto;emit-summary")
+    parseFatLTOOptions, "O0;O1;O2;O3;thinlto;emit-summary")
 
 #undef MODULE_PASS_WITH_PARAMS
 
@@ -604,7 +604,7 @@ FUNCTION_PASS_WITH_PARAMS(
     [this](OptimizationLevel OL) {
       return buildFunctionSimplificationPipeline(OL, ThinOrFullLTOPhase::None);
     },
-    parseFunctionSimplificationPipelineOptions, "O1;O2;O3;Os;Oz")
+    parseFunctionSimplificationPipelineOptions, "O1;O2;O3")
 FUNCTION_PASS_WITH_PARAMS(
     "gvn", "GVNPass", [](GVNOptions Opts) { return GVNPass(Opts); },
     parseGVNOptions,