[LTO][NewPM] Run verifier when doing LTO

[aeubanks]

Summary

This matches the legacy PM.

[ychen]

LGTM.

lld/test/ELF/lto/verify-invalid.ll

 ; REQUIRES: x86
 ; RUN: llvm-as %s -o %t.o
 ; RUN: ld.lld %t.o -o %t2 -mllvm -debug-pass=Arguments \
-; RUN:   2>&1 | FileCheck -check-prefix=DEFAULT %s
+; RUN:   2>&1 | FileCheck -check-prefix=DEFAULT-LPM %s
 ; RUN: ld.lld %t.o -o %t2 -mllvm -debug-pass=Arguments \
-; RUN:   -disable-verify 2>&1 | FileCheck -check-prefix=DISABLE %s
+; RUN:   -disable-verify 2>&1 | FileCheck -check-prefix=DISABLE-LPM %s
 ; RUN: ld.lld %t.o -o %t2 -mllvm -debug-pass=Arguments \
-; RUN:   --plugin-opt=disable-verify 2>&1 | FileCheck -check-prefix=DISABLE %s
+; RUN:   --plugin-opt=disable-verify 2>&1 | FileCheck -check-prefix=DISABLE-LPM %s
+; RUN: ld.lld %t.o -o %t2 --lto-new-pass-manager --lto-debug-pass-manager \
+; RUN:   2>&1 | FileCheck -check-prefix=DEFAULT-NPM %s
+; RUN: ld.lld %t.o -o %t2 --lto-new-pass-manager --lto-debug-pass-manager \
+; RUN:   -disable-verify 2>&1 | FileCheck -check-prefix=DISABLE-NPM %s
+; RUN: ld.lld %t.o -o %t2 --lto-new-pass-manager --lto-debug-pass-manager \
+; RUN:   --plugin-opt=disable-verify 2>&1 | FileCheck -check-prefix=DISABLE-NPM %s
 
 target triple = "x86_64-unknown-linux-gnu"
 target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
 
 define void @_start() {
   ret void
 }
 
 ; -disable-verify should disable the verification of bitcode.
-; DEFAULT:     Pass Arguments: {{.*}} -verify {{.*}} -verify
-; DISABLE-NOT: Pass Arguments: {{.*}} -verify {{.*}} -verify
+; DEFAULT-LPM:     Pass Arguments: {{.*}} -verify {{.*}} -verify
+; DISABLE-LPM-NOT: Pass Arguments: {{.*}} -verify {{.*}} -verify
+; DEFAULT-NPM: Running pass: VerifierPass
+; DEFAULT-NPM: Running pass: VerifierPass
+; DEFAULT-NPM-NOT: Running pass: VerifierPass
+; DISABLE-NPM-NOT: Running pass: VerifierPass

llvm/lib/LTO/LTOBackend.cpp

static void runNewPMPasses(const Config &Conf, Module &Mod, TargetMachine *TM,
   // Register all the basic analyses with the managers.
   PB.registerModuleAnalyses(MAM);
   PB.registerCGSCCAnalyses(CGAM);
   PB.registerFunctionAnalyses(FAM);
   PB.registerLoopAnalyses(LAM);
   PB.crossRegisterProxies(LAM, FAM, CGAM, MAM);
 
   ModulePassManager MPM(Conf.DebugPassManager);
-  // FIXME (davide): verify the input.
+
+  if (!Conf.DisableVerify)
+    MPM.addPass(VerifierPass());
 
   PassBuilder::OptimizationLevel OL;
 
   switch (OptLevel) {
   default:
     llvm_unreachable("Invalid optimization level");
   case 0:
     OL = PassBuilder::OptimizationLevel::O0;
     break;
   case 1:
     OL = PassBuilder::OptimizationLevel::O1;
     break;
   case 2:
     OL = PassBuilder::OptimizationLevel::O2;
     break;
   case 3:
     OL = PassBuilder::OptimizationLevel::O3;
     break;
   }
 
   if (IsThinLTO)
-    MPM = PB.buildThinLTODefaultPipeline(OL, ImportSummary);
+    MPM.addPass(PB.buildThinLTODefaultPipeline(OL, ImportSummary));
   else
-    MPM = PB.buildLTODefaultPipeline(OL, ExportSummary);
-  MPM.run(Mod, MAM);
+    MPM.addPass(PB.buildLTODefaultPipeline(OL, ExportSummary));
 
-  // FIXME (davide): verify the output.
+  if (!Conf.DisableVerify)
+    MPM.addPass(VerifierPass());
+
+  MPM.run(Mod, MAM);
 }
 
 static void runNewPMCustomPasses(const Config &Conf, Module &Mod,
                                  TargetMachine *TM, std::string PipelineDesc,
                                  std::string AAPipelineDesc,
                                  bool DisableVerify) {
   PassBuilder PB(Conf.DebugPassManager, TM);
   AAManager AA;