diff --git a/lib/Passes/PassBuilder.cpp b/lib/Passes/PassBuilder.cpp
index 32e31cbc0f4..1b4bffc0752 100644
--- a/lib/Passes/PassBuilder.cpp
+++ b/lib/Passes/PassBuilder.cpp
@@ -1046,10 +1046,16 @@ ModulePassManager PassBuilder::buildThinLTODefaultPipeline(
     //
     // Also, WPD has access to more precise information than ICP and can
     // devirtualize more effectively, so it should operate on the IR first.
+    //
+    // The WPD and LowerTypeTest passes need to run at -O0 to lower type
+    // metadata and intrinsics.
     MPM.addPass(WholeProgramDevirtPass(nullptr, ImportSummary));
     MPM.addPass(LowerTypeTestsPass(nullptr, ImportSummary));
   }
 
+  if (Level == O0)
+    return MPM;
+
   // Force any function attributes we want the rest of the pipeline to observe.
   MPM.addPass(ForceFunctionAttrsPass());
 
@@ -1075,9 +1081,16 @@ PassBuilder::buildLTOPreLinkDefaultPipeline(OptimizationLevel Level,
 ModulePassManager
 PassBuilder::buildLTODefaultPipeline(OptimizationLevel Level, bool DebugLogging,
                                      ModuleSummaryIndex *ExportSummary) {
-  assert(Level != O0 && "Must request optimizations for the default pipeline!");
   ModulePassManager MPM(DebugLogging);
 
+  if (Level == O0) {
+    // The WPD and LowerTypeTest passes need to run at -O0 to lower type
+    // metadata and intrinsics.
+    MPM.addPass(WholeProgramDevirtPass(ExportSummary, nullptr));
+    MPM.addPass(LowerTypeTestsPass(ExportSummary, nullptr));
+    return MPM;
+  }
+
   if (PGOOpt && PGOOpt->Action == PGOOptions::SampleUse) {
     // Load sample profile before running the LTO optimization pipeline.
     MPM.addPass(SampleProfileLoaderPass(PGOOpt->ProfileFile,
diff --git a/test/tools/gold/X86/opt-level.ll b/test/tools/gold/X86/opt-level.ll
index 33317ea22f1..bd49e096a7d 100644
--- a/test/tools/gold/X86/opt-level.ll
+++ b/test/tools/gold/X86/opt-level.ll
@@ -6,12 +6,25 @@
 ; RUN: %gold -plugin %llvmshlibdir/LLVMgold%shlibext -plugin-opt=save-temps \
 ; RUN:    -m elf_x86_64 \
 ; RUN:    -plugin-opt=O1 -r -o %t.o %t.bc
-; RUN: llvm-dis < %t.o.0.4.opt.bc -o - | FileCheck --check-prefix=CHECK-O1 %s
+; RUN: llvm-dis < %t.o.0.4.opt.bc -o - | FileCheck --check-prefix=CHECK-O1 --check-prefix=CHECK-O1-OLDPM %s
 ; RUN: %gold -plugin %llvmshlibdir/LLVMgold%shlibext -plugin-opt=save-temps \
 ; RUN:    -m elf_x86_64 \
 ; RUN:    -plugin-opt=O2 -r -o %t.o %t.bc
 ; RUN: llvm-dis < %t.o.0.4.opt.bc -o - | FileCheck --check-prefix=CHECK-O2 %s
 
+; RUN: %gold -plugin %llvmshlibdir/LLVMgold%shlibext -plugin-opt=save-temps \
+; RUN:    -m elf_x86_64 --plugin-opt=new-pass-manager \
+; RUN:    -plugin-opt=O0 -r -o %t.o %t.bc
+; RUN: llvm-dis < %t.o.0.4.opt.bc -o - | FileCheck --check-prefix=CHECK-O0 %s
+; RUN: %gold -plugin %llvmshlibdir/LLVMgold%shlibext -plugin-opt=save-temps \
+; RUN:    -m elf_x86_64 --plugin-opt=new-pass-manager \
+; RUN:    -plugin-opt=O1 -r -o %t.o %t.bc
+; RUN: llvm-dis < %t.o.0.4.opt.bc -o - | FileCheck --check-prefix=CHECK-O1 --check-prefix=CHECK-O1-NEWPM %s
+; RUN: %gold -plugin %llvmshlibdir/LLVMgold%shlibext -plugin-opt=save-temps \
+; RUN:    -m elf_x86_64 --plugin-opt=new-pass-manager \
+; RUN:    -plugin-opt=O2 -r -o %t.o %t.bc
+; RUN: llvm-dis < %t.o.0.4.opt.bc -o - | FileCheck --check-prefix=CHECK-O2 %s
+
 ; CHECK-O0: define internal void @foo(
 ; CHECK-O1: define internal void @foo(
 ; CHECK-O2-NOT: define internal void @foo(
@@ -36,7 +49,9 @@ f:
 
 end:
   ; CHECK-O0: phi
-  ; CHECK-O1: select
+  ; CHECK-O1-OLDPM: select
+  ; The new PM does not do as many optimizations at O1
+  ; CHECK-O1-NEWPM: phi
   %r = phi i32 [ 1, %t ], [ 2, %f ]
   ret i32 %r
 }