[opt] Cleanups related to legacy PM deprecation

[bjope]

Summary

Remove dead code related to "FPasses". This was a leftover from
commit 7a5332b9b5584ce.

Do not mention -enable-new-pm in error messages. The option does
not exist any longer.

Remove the addPass helper. Only one use remained, so we can just
"inline" it manually to keep the code related to legacy PM a bit
less spread out.

llvm/tools/opt/opt.cpp

static cl::opt<std::string> RemarksFormat(
     "pass-remarks-format",
     cl::desc("The format used for serializing remarks (default: YAML)"),
     cl::value_desc("format"), cl::init("yaml"));
 
 static cl::list<std::string>
     PassPlugins("load-pass-plugin",
                 cl::desc("Load passes from plugin library"));
 
-static inline void addPass(legacy::PassManagerBase &PM, Pass *P) {
-  // Add the pass to the pass manager...
-  PM.add(P);
-
-  // If we are verifying all of the intermediate steps, add the verifier...
-  if (VerifyEach)
-    PM.add(createVerifierPass());
-}
-
 //===----------------------------------------------------------------------===//
 // CodeGen-related helper functions.
 //
 
 static CodeGenOpt::Level GetCodeGenOptLevel() {
   return static_cast<CodeGenOpt::Level>(unsigned(CodeGenOptLevel));
 }
 
for (auto &FuncName : DisableBuiltins)
         errs() << argv[0] << ": cannot disable nonexistent builtin function "
                << FuncName << '\n';
         return 1;
       }
   }
 
   if (UseNPM) {
     if (legacy::debugPassSpecified()) {
-      errs()
-          << "-debug-pass does not work with the new PM, either use "
-             "-debug-pass-manager, or use the legacy PM (-enable-new-pm=0)\n";
+      errs() << "-debug-pass does not work with the new PM, either use "
+                "-debug-pass-manager, or use the legacy PM\n";
       return 1;
     }
     auto NumOLevel = OptLevelO0 + OptLevelO1 + OptLevelO2 + OptLevelO3 +
                      OptLevelOs + OptLevelOz;
     if (NumOLevel > 1) {
       errs() << "Cannot specify multiple -O#\n";
       return 1;
     }
if (AddOneTimeDebugifyPasses) {
     } else if (VerifyDebugInfoPreserve) {
       Passes.setDebugInfoBeforePass(DebugInfoBeforePass);
       Passes.add(createDebugifyModulePass(
           DebugifyMode::OriginalDebugInfo, "",
           &(Passes.getDebugInfoPerPass())));
     }
   }
 
-  std::unique_ptr<legacy::FunctionPassManager> FPasses;
-
   if (TM) {
     // FIXME: We should dyn_cast this when supported.
     auto &LTM = static_cast<LLVMTargetMachine &>(*TM);
     Pass *TPC = LTM.createPassConfig(Passes);
     Passes.add(TPC);
   }
 
   // Create a new optimization pass for each one specified on the command line
   for (unsigned i = 0; i < PassList.size(); ++i) {
     const PassInfo *PassInf = PassList[i];
-    Pass *P = nullptr;
-    if (PassInf->getNormalCtor())
-      P = PassInf->getNormalCtor()();
-    else
+    if (PassInf->getNormalCtor()) {
+      Pass *P = PassInf->getNormalCtor()();
+      if (P) {
+        // Add the pass to the pass manager.
+        Passes.add(P);
+        // If we are verifying all of the intermediate steps, add the verifier.
+        if (VerifyEach)
+          Passes.add(createVerifierPass());
+      }
+    } else
       errs() << argv[0] << ": cannot create pass: "
              << PassInf->getPassName() << "\n";
-    if (P)
-      addPass(Passes, P);
-  }
-
-  if (FPasses) {
-    FPasses->doInitialization();
-    for (Function &F : *M)
-      FPasses->run(F);
-    FPasses->doFinalization();
   }
 
   // Check that the module is well formed on completion of optimization
   if (!NoVerify && !VerifyEach)
     Passes.add(createVerifierPass());
 
   if (AddOneTimeDebugifyPasses) {
     if (EnableDebugify)