[clang] Run LLVM Verifier in modes without CodeGen too

Previously, the Backend_Emit{Nothing,BC,LL} modes did
not run the LLVM verifier since it is usually added via
the TargetMachine::addPassesToEmitFile method according
to the DisableVerify parameter. This is called from
EmitAssemblyHelper::AddEmitPasses, which is only relevant
for BackendAction-s that require CodeGen.

Note:
* In these particular situations the verifier is added
  to the optimization pipeline rather than the codegen
  pipeline so that it runs prior to the BC/LL emission
  pass.
* This change applies to both the old and the new PMs.
* Because the clang tests use -emit-llvm ubiquitously,
  this change will enable the verifier for them.
* A small bug is fixed in emitIFuncDefinition so that
  the clang/test/CodeGen/ifunc.c test would pass:
  the emitIFuncDefinition incorrectly passed the
  GlobalDecl of the IFunc itself to the call to
  GetOrCreateLLVMFunction for creating the resolver.

Signed-off-by: Itay Bookstein <[email protected]>

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D113352

Author: ibookstein

clang/lib/CodeGen/BackendUtil.cpp

@@ -487,6 +487,11 @@ static CodeGenFileType getCodeGenFileType(BackendAction Action) {
   }
 }
 
+static bool actionRequiresCodeGen(BackendAction Action) {
+  return Action != Backend_EmitNothing && Action != Backend_EmitBC &&
+         Action != Backend_EmitLL;
+}
+
 static bool initTargetOptions(DiagnosticsEngine &Diags,
                               llvm::TargetOptions &Options,
                               const CodeGenOptions &CodeGenOpts,
@@ -977,9 +982,7 @@ void EmitAssemblyHelper::EmitAssemblyWithLegacyPassManager(
 
   setCommandLineOpts(CodeGenOpts);
 
-  bool UsesCodeGen = (Action != Backend_EmitNothing &&
-                      Action != Backend_EmitBC &&
-                      Action != Backend_EmitLL);
+  bool UsesCodeGen = actionRequiresCodeGen(Action);
   CreateTargetMachine(UsesCodeGen);
 
   if (UsesCodeGen && !TM)
@@ -1006,6 +1009,12 @@ void EmitAssemblyHelper::EmitAssemblyWithLegacyPassManager(
 
   CreatePasses(PerModulePasses, PerFunctionPasses);
 
+  // Add a verifier pass if requested. We don't have to do this if the action
+  // requires code generation because there will already be a verifier pass in
+  // the code-generation pipeline.
+  if (!UsesCodeGen && CodeGenOpts.VerifyModule)
+    PerModulePasses.add(createVerifierPass());
+
   legacy::PassManager CodeGenPasses;
   CodeGenPasses.add(
       createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
@@ -1425,6 +1434,13 @@ void EmitAssemblyHelper::RunOptimizationPipeline(
       MPM.addPass(ModuleMemProfilerPass());
     }
   }
+
+  // Add a verifier pass if requested. We don't have to do this if the action
+  // requires code generation because there will already be a verifier pass in
+  // the code-generation pipeline.
+  if (!actionRequiresCodeGen(Action) && CodeGenOpts.VerifyModule)
+    MPM.addPass(VerifierPass());
+
   switch (Action) {
   case Backend_EmitBC:
     if (CodeGenOpts.PrepareForThinLTO && !CodeGenOpts.DisableLLVMPasses) {
@@ -1514,8 +1530,7 @@ void EmitAssemblyHelper::EmitAssembly(BackendAction Action,
   TimeRegion Region(CodeGenOpts.TimePasses ? &CodeGenerationTime : nullptr);
   setCommandLineOpts(CodeGenOpts);
 
-  bool RequiresCodeGen = (Action != Backend_EmitNothing &&
-                          Action != Backend_EmitBC && Action != Backend_EmitLL);
+  bool RequiresCodeGen = actionRequiresCodeGen(Action);
   CreateTargetMachine(RequiresCodeGen);
 
   if (RequiresCodeGen && !TM)

clang/lib/CodeGen/CodeGenModule.cpp

@@ -5034,7 +5034,7 @@ void CodeGenModule::emitIFuncDefinition(GlobalDecl GD) {
   llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType());
   llvm::Type *ResolverTy = llvm::GlobalIFunc::getResolverFunctionType(DeclTy);
   llvm::Constant *Resolver =
-      GetOrCreateLLVMFunction(IFA->getResolver(), ResolverTy, GD,
+      GetOrCreateLLVMFunction(IFA->getResolver(), ResolverTy, {},
                               /*ForVTable=*/false);
   llvm::GlobalIFunc *GIF =
       llvm::GlobalIFunc::create(DeclTy, 0, llvm::Function::ExternalLinkage,

clang/test/CodeGen/lto-newpm-pipeline.c

@@ -32,6 +32,8 @@
 // CHECK-FULL-O0-NEXT: Running pass: CoroCleanupPass
 // CHECK-FULL-O0-NEXT: Running pass: CanonicalizeAliasesPass
 // CHECK-FULL-O0-NEXT: Running pass: NameAnonGlobalPass
+// CHECK-FULL-O0-NEXT: Running pass: VerifierPass
+// CHECK-FULL-O0-NEXT: Running analysis: VerifierAnalysis
 // CHECK-FULL-O0-NEXT: Running pass: BitcodeWriterPass
 
 // CHECK-THIN-O0: Running pass: AlwaysInlinerPass
@@ -40,6 +42,8 @@
 // CHECK-THIN-O0: Running pass: CoroCleanupPass
 // CHECK-THIN-O0-NEXT: Running pass: CanonicalizeAliasesPass
 // CHECK-THIN-O0-NEXT: Running pass: NameAnonGlobalPass
+// CHECK-THIN-O0-NEXT: Running pass: VerifierPass
+// CHECK-THIN-O0-NEXT: Running analysis: VerifierAnalysis
 // CHECK-THIN-O0-NEXT: Running pass: ThinLTOBitcodeWriterPass
 
 // TODO: The LTO pre-link pipeline currently invokes