Revert "[IR] Lazily initialize the class to pass name mapping (NFC) (#96321)"

My attempt to fix the Windows build made things worse,
revert entirely for now.

This reverts commit e7137f2fed5cfee822ae3c4c6d39188adb59a16c.
This reverts commit 6eaf204dbb0a6a81cddfd02f625c130f7bb1aae5.
This reverts commit 957dc4366dd2ce9d5d2991c3ad76bbf438e9954e.

1 files changed, 15 insertions, 4 deletions

diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
index 12ef995..f819345 100644
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -325,6 +325,18 @@ AnalysisKey NoOpLoopAnalysis::Key;
 
 namespace {
 
+/// Whether or not we should populate a PassInstrumentationCallbacks's class to
+/// pass name map.
+///
+/// This is for optimization purposes so we don't populate it if we never use
+/// it. This should be updated if new pass instrumentation wants to use the map.
+/// We currently only use this for --print-before/after.
+bool shouldPopulateClassToPassNames() {
+  return PrintPipelinePasses || !printBeforePasses().empty() ||
+         !printAfterPasses().empty() || !isFilterPassesEmpty() ||
+         TargetPassConfig::hasLimitedCodeGenPipeline();
+}
+
 // A pass for testing -print-on-crash.
 // DO NOT USE THIS EXCEPT FOR TESTING!
 class TriggerCrashPass : public PassInfoMixin<TriggerCrashPass> {
@@ -404,10 +416,10 @@ PassBuilder::PassBuilder(TargetMachine *TM, PipelineTuningOptions PTO,
                          std::optional<PGOOptions> PGOOpt,
                          PassInstrumentationCallbacks *PIC)
     : TM(TM), PTO(PTO), PGOOpt(PGOOpt), PIC(PIC) {
+  bool ShouldPopulateClassToPassNames = PIC && shouldPopulateClassToPassNames();
   if (TM)
-    TM->registerPassBuilderCallbacks(*this);
-  if (PIC) {
-    PIC->registerClassToPassNameCallback([PIC]() {
+    TM->registerPassBuilderCallbacks(*this, ShouldPopulateClassToPassNames);
+  if (ShouldPopulateClassToPassNames) {
 #define MODULE_PASS(NAME, CREATE_PASS)                                         \
   PIC->addClassToPassName(decltype(CREATE_PASS)::name(), NAME);
 #define MODULE_PASS_WITH_PARAMS(NAME, CLASS, CREATE_PASS, PARSER, PARAMS)      \
@@ -441,7 +453,6 @@ PassBuilder::PassBuilder(TargetMachine *TM, PipelineTuningOptions PTO,
 #define MACHINE_FUNCTION_PASS(NAME, CREATE_PASS)                               \
   PIC->addClassToPassName(decltype(CREATE_PASS)::name(), NAME);
 #include "llvm/Passes/MachinePassRegistry.def"
-    });
   }
 }