Run Coverage pass before other *San passes under new pass manager, round 2

Summary:
This was attempted once before in https://reviews.llvm.org/D79698, but
was reverted due to the coverage pass running in the wrong part of the
pipeline. This commit puts it in the same place as the other sanitizers.

This changes PassBuilder.OptimizerLastEPCallbacks to work on a
ModulePassManager instead of a FunctionPassManager. That is because
SanitizerCoverage cannot (easily) be split into a module pass and a
function pass like some of the other sanitizers since in its current
implementation it conditionally inserts module constructors based on
whether or not it successfully modified functions.

This fixes compiler-rt/test/msan/coverage-levels.cpp under the new pass
manager (last check-msan test).

Currently sanitizers + LTO don't work together under the new pass
manager, so I removed tests that checked that this combination works for
sancov.

Subscribers: hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D80692

include/llvm/Passes/PassBuilder.h

@@ -600,7 +600,7 @@ public:
   /// is not triggered at O0. Extensions to the O0 pipeline should append their
   /// passes to the end of the overall pipeline.
   void registerOptimizerLastEPCallback(
-      const std::function<void(FunctionPassManager &, OptimizationLevel)> &C) {
+      const std::function<void(ModulePassManager &, OptimizationLevel)> &C) {
     OptimizerLastEPCallbacks.push_back(C);
   }
 
@@ -728,7 +728,7 @@ private:
       CGSCCOptimizerLateEPCallbacks;
   SmallVector<std::function<void(FunctionPassManager &, OptimizationLevel)>, 2>
       VectorizerStartEPCallbacks;
-  SmallVector<std::function<void(FunctionPassManager &, OptimizationLevel)>, 2>
+  SmallVector<std::function<void(ModulePassManager &, OptimizationLevel)>, 2>
       OptimizerLastEPCallbacks;
   // Module callbacks
   SmallVector<std::function<void(ModulePassManager &)>, 2>

lib/Passes/PassBuilder.cpp

@@ -1073,12 +1073,12 @@ ModulePassManager PassBuilder::buildModuleOptimizationPipeline(
   if (PTO.Coroutines)
     OptimizePM.addPass(CoroCleanupPass());
 
-  for (auto &C : OptimizerLastEPCallbacks)
-    C(OptimizePM, Level);
-
   // Add the core optimizing pipeline.
   MPM.addPass(createModuleToFunctionPassAdaptor(std::move(OptimizePM)));
 
+  for (auto &C : OptimizerLastEPCallbacks)
+    C(MPM, Level);
+
   if (PTO.CallGraphProfile)
     MPM.addPass(CGProfilePass());
 

tools/opt/NewPMDriver.cpp

@@ -194,7 +194,7 @@ static void registerEPCallbacks(PassBuilder &PB, bool VerifyEachPass,
         });
   if (tryParsePipelineText<FunctionPassManager>(PB, OptimizerLastEPPipeline))
     PB.registerOptimizerLastEPCallback(
-        [&PB, VerifyEachPass, DebugLogging](FunctionPassManager &PM,
+        [&PB, VerifyEachPass, DebugLogging](ModulePassManager &PM,
                                             PassBuilder::OptimizationLevel) {
           ExitOnError Err("Unable to parse OptimizerLastEP pipeline: ");
           Err(PB.parsePassPipeline(PM, OptimizerLastEPPipeline, VerifyEachPass,