diff --git a/llvm/include/llvm/Passes/PassBuilder.h b/llvm/include/llvm/Passes/PassBuilder.h
index e6ced0cccb9b3c..0ebfdbb7865fdd 100644
--- a/llvm/include/llvm/Passes/PassBuilder.h
+++ b/llvm/include/llvm/Passes/PassBuilder.h
@@ -245,8 +245,9 @@ class PassBuilder {
   /// optimization and code generation without any link-time optimization. It
   /// typically correspond to frontend "-O[123]" options for optimization
   /// levels \c O1, \c O2 and \c O3 resp.
-  ModulePassManager buildPerModuleDefaultPipeline(OptimizationLevel Level,
-                                                  bool LTOPreLink = false);
+  ModulePassManager buildPerModuleDefaultPipeline(
+      OptimizationLevel Level,
+      ThinOrFullLTOPhase Phase = ThinOrFullLTOPhase::None);
 
   /// Build a fat object default optimization pipeline.
   ///
@@ -296,8 +297,9 @@ class PassBuilder {
   /// Build an O0 pipeline with the minimal semantically required passes.
   ///
   /// This should only be used for non-LTO and LTO pre-link pipelines.
-  ModulePassManager buildO0DefaultPipeline(OptimizationLevel Level,
-                                           bool LTOPreLink = false);
+  ModulePassManager
+  buildO0DefaultPipeline(OptimizationLevel Level,
+                         ThinOrFullLTOPhase Phase = ThinOrFullLTOPhase::None);
 
   /// Build the default `AAManager` with the default alias analysis pipeline
   /// registered.
diff --git a/llvm/lib/Passes/PassBuilderPipelines.cpp b/llvm/lib/Passes/PassBuilderPipelines.cpp
index 3f28dd39911f79..466fbcd7bb7703 100644
--- a/llvm/lib/Passes/PassBuilderPipelines.cpp
+++ b/llvm/lib/Passes/PassBuilderPipelines.cpp
@@ -1601,9 +1601,9 @@ PassBuilder::buildModuleOptimizationPipeline(OptimizationLevel Level,
 
 ModulePassManager
 PassBuilder::buildPerModuleDefaultPipeline(OptimizationLevel Level,
-                                           bool LTOPreLink) {
+                                           ThinOrFullLTOPhase Phase) {
   if (Level == OptimizationLevel::O0)
-    return buildO0DefaultPipeline(Level, LTOPreLink);
+    return buildO0DefaultPipeline(Level, Phase);
 
   ModulePassManager MPM;
 
@@ -1619,14 +1619,11 @@ PassBuilder::buildPerModuleDefaultPipeline(OptimizationLevel Level,
   // Apply module pipeline start EP callback.
   invokePipelineStartEPCallbacks(MPM, Level);
 
-  const ThinOrFullLTOPhase LTOPhase = LTOPreLink
-                                          ? ThinOrFullLTOPhase::FullLTOPreLink
-                                          : ThinOrFullLTOPhase::None;
   // Add the core simplification pipeline.
-  MPM.addPass(buildModuleSimplificationPipeline(Level, LTOPhase));
+  MPM.addPass(buildModuleSimplificationPipeline(Level, Phase));
 
   // Now add the optimization pipeline.
-  MPM.addPass(buildModuleOptimizationPipeline(Level, LTOPhase));
+  MPM.addPass(buildModuleOptimizationPipeline(Level, Phase));
 
   if (PGOOpt && PGOOpt->PseudoProbeForProfiling &&
       PGOOpt->Action == PGOOptions::SampleUse)
@@ -1635,7 +1632,7 @@ PassBuilder::buildPerModuleDefaultPipeline(OptimizationLevel Level,
   // Emit annotation remarks.
   addAnnotationRemarksPass(MPM);
 
-  if (LTOPreLink)
+  if (isLTOPreLink(Phase))
     addRequiredLTOPreLinkPasses(MPM);
   return MPM;
 }
@@ -1673,7 +1670,7 @@ PassBuilder::buildFatLTODefaultPipeline(OptimizationLevel Level, bool ThinLTO,
 ModulePassManager
 PassBuilder::buildThinLTOPreLinkDefaultPipeline(OptimizationLevel Level) {
   if (Level == OptimizationLevel::O0)
-    return buildO0DefaultPipeline(Level, /*LTOPreLink*/true);
+    return buildO0DefaultPipeline(Level, ThinOrFullLTOPhase::ThinLTOPreLink);
 
   ModulePassManager MPM;
 
@@ -1794,7 +1791,7 @@ ModulePassManager
 PassBuilder::buildLTOPreLinkDefaultPipeline(OptimizationLevel Level) {
   // FIXME: We should use a customized pre-link pipeline!
   return buildPerModuleDefaultPipeline(Level,
-                                       /* LTOPreLink */ true);
+                                       ThinOrFullLTOPhase::FullLTOPreLink);
 }
 
 ModulePassManager
@@ -2124,8 +2121,9 @@ PassBuilder::buildLTODefaultPipeline(OptimizationLevel Level,
   return MPM;
 }
 
-ModulePassManager PassBuilder::buildO0DefaultPipeline(OptimizationLevel Level,
-                                                      bool LTOPreLink) {
+ModulePassManager
+PassBuilder::buildO0DefaultPipeline(OptimizationLevel Level,
+                                    ThinOrFullLTOPhase Phase) {
   assert(Level == OptimizationLevel::O0 &&
          "buildO0DefaultPipeline should only be used with O0");
 
@@ -2220,7 +2218,7 @@ ModulePassManager PassBuilder::buildO0DefaultPipeline(OptimizationLevel Level,
 
   invokeOptimizerLastEPCallbacks(MPM, Level);
 
-  if (LTOPreLink)
+  if (isLTOPreLink(Phase))
     addRequiredLTOPreLinkPasses(MPM);
 
   MPM.addPass(createModuleToFunctionPassAdaptor(AnnotationRemarksPass()));