[mlir] Add asserts when changing various MLIRContext configurations

[rriddle]

Summary

This helps to prevent tsan failures when users inadvertantly mutate the
context in a non-safe way.

[mehdi_amini]

Thanks!

[nicolasvasilache]

mlir/lib/IR/MLIRContext.cpp

357

I have a general question here on the registration requirements with nested passes.

Is there a good rule of thumb for dependent dialects, external models and dynamically injected ops mixed with nested passes?
It seems that a mechanism to declare dependent passes would be a good QoL improvement: it does not seem manageable for nested pass writers to have to manually add registration for everything in dependent passes.

Am I missing something?

[mehdi_amini]

mlir/lib/IR/MLIRContext.cpp

357

Dependent dialects is supposed to be handle recursively, which admittedly can be tricky sometimes. I think the IREE HAL handles it properly as an example: https://github.com/google/iree/blob/main/iree/compiler/Dialect/HAL/Transforms/TranslateExecutables.cpp#L46-L53

External models are supposed to be injected by IR producers, if this is part of a nested pass, the pass that nest this can handle this in getDependentDialects() as well.

mlir/lib/IR/MLIRContext.cpp

 /// Returns the diagnostic engine for this context.
 DiagnosticEngine &MLIRContext::getDiagEngine() { return getImpl().diagEngine; }
 
 //===----------------------------------------------------------------------===//
 // Dialect and Operation Registration
 //===----------------------------------------------------------------------===//
 
 void MLIRContext::appendDialectRegistry(const DialectRegistry &registry) {
+  assert(impl->multiThreadedExecutionContext == 0 &&
+         "appending to the MLIRContext dialect registry while in a "
+         "multi-threaded execution context");
   registry.appendTo(impl->dialectsRegistry);
 
   // For the already loaded dialects, register the interfaces immediately.
   for (const auto &kvp : impl->loadedDialects)
     registry.registerDelayedInterfaces(kvp.second.get());
 }
 
 const DialectRegistry &MLIRContext::getDialectRegistry() {
   return impl->dialectsRegistry;
llvm::hash_code MLIRContext::getRegistryHash() {
   return hash;
 }
 
 bool MLIRContext::allowsUnregisteredDialects() {
   return impl->allowUnregisteredDialects;
 }
 
 void MLIRContext::allowUnregisteredDialects(bool allowing) {
+  assert(impl->multiThreadedExecutionContext == 0 &&
+         "changing MLIRContext `allow-unregistered-dialects` configuration "
+         "while in a multi-threaded execution context");
   impl->allowUnregisteredDialects = allowing;
 }
 
 /// Return true if multi-threading is enabled by the context.
 bool MLIRContext::isMultithreadingEnabled() {
   return impl->threadingIsEnabled && llvm::llvm_is_multithreaded();
 }
 
 /// Set the flag specifying if multi-threading is disabled by the context.
 void MLIRContext::disableMultithreading(bool disable) {
   // This API can be overridden by the global debugging flag
   // --mlir-disable-threading
   if (isThreadingGloballyDisabled())
     return;
+  assert(impl->multiThreadedExecutionContext == 0 &&
+         "changing MLIRContext `disable-threading` configuration while "
+         "in a multi-threaded execution context");
 
   impl->threadingIsEnabled = !disable;
 
   // Update the threading mode for each of the uniquers.
   impl->affineUniquer.disableMultithreading(disable);
   impl->attributeUniquer.disableMultithreading(disable);
   impl->typeUniquer.disableMultithreading(disable);
 

 /// Operation::emit.
 bool MLIRContext::shouldPrintOpOnDiagnostic() {
   return impl->printOpOnDiagnostic;
 }
 
 /// Set the flag specifying if we should attach the operation to diagnostics
 /// emitted via Operation::emit.
 void MLIRContext::printOpOnDiagnostic(bool enable) {
+  assert(impl->multiThreadedExecutionContext == 0 &&
+         "changing MLIRContext `print-op-on-diagnostic` configuration while in "
+         "a multi-threaded execution context");
   impl->printOpOnDiagnostic = enable;
 }
 
 /// Return true if we should attach the current stacktrace to diagnostics when
 /// emitted.
 bool MLIRContext::shouldPrintStackTraceOnDiagnostic() {
   return impl->printStackTraceOnDiagnostic;
 }
 
 /// Set the flag specifying if we should attach the current stacktrace when
 /// emitting diagnostics.
 void MLIRContext::printStackTraceOnDiagnostic(bool enable) {
+  assert(impl->multiThreadedExecutionContext == 0 &&
+         "changing MLIRContext `print-stacktrace-on-diagnostic` configuration "
+         "while in a multi-threaded execution context");
   impl->printStackTraceOnDiagnostic = enable;
 }
 
 /// Return information about all registered operations.  This isn't very
 /// efficient, typically you should ask the operations about their properties
 /// directly.
 std::vector<RegisteredOperationName> MLIRContext::getRegisteredOperations() {
   // We just have the operations in a non-deterministic hash table order. Dump

mlir/lib/Reducer/OptReductionPass.cpp

 void OptReductionPass::runOnOperation() {
   LLVM_DEBUG(llvm::dbgs() << "\nOptimization Reduction pass: ");
 
   Tester test(testerName, testerArgs);
 
   ModuleOp module = this->getOperation();
   ModuleOp moduleVariant = module.clone();
 
-  PassManager passManager(module.getContext());
+  OpPassManager passManager("builtin.module");
   if (failed(parsePassPipeline(optPass, passManager))) {
     module.emitError() << "\nfailed to parse pass pipeline";
     return signalPassFailure();
   }
 
   std::pair<Tester::Interestingness, int> original = test.isInteresting(module);
   if (original.first != Tester::Interestingness::True) {
     module.emitError() << "\nthe original input is not interested";
     return signalPassFailure();
   }
 
-  if (failed(passManager.run(moduleVariant))) {
+  // Temporarily push the variant under the main module and execute the pipeline
+  // on it.
+  module.getBody()->push_back(moduleVariant);
+  LogicalResult pipelineResult = runPipeline(passManager, moduleVariant);
+  moduleVariant->remove();
+
+  if (failed(pipelineResult)) {
     module.emitError() << "\nfailed to run pass pipeline";
     return signalPassFailure();
   }
 
   std::pair<Tester::Interestingness, int> reduced =
       test.isInteresting(moduleVariant);
 
   if (reduced.first == Tester::Interestingness::True &&

mlir/test/lib/Dialect/Linalg/TestLinalgFusionTransforms.cpp

struct TestLinalgGreedyFusion
   }
   void runOnFunction() override {
     MLIRContext *context = &getContext();
     RewritePatternSet patterns =
         linalg::getLinalgTilingCanonicalizationPatterns(context);
     patterns.add<ExtractSliceOfPadTensorSwapPattern>(context);
     scf::populateSCFForLoopCanonicalizationPatterns(patterns);
     FrozenRewritePatternSet frozenPatterns(std::move(patterns));
-    do {
-      (void)applyPatternsAndFoldGreedily(getFunction(), frozenPatterns);
-      PassManager pm(context);
-      pm.addPass(createLoopInvariantCodeMotionPass());
-      pm.addPass(createCanonicalizerPass());
-      pm.addPass(createCSEPass());
-      LogicalResult res = pm.run(getFunction()->getParentOfType<ModuleOp>());
-      if (failed(res))
+    OpPassManager pm(FuncOp::getOperationName());
+    do {
+      (void)applyPatternsAndFoldGreedily(getFunction(), frozenPatterns);
+      if (failed(runPipeline(pm, getFunction())))
         this->signalPassFailure();
     } while (succeeded(fuseLinalgOpsGreedily(getFunction())));
   }
 };
 
 /// Pass to test tile and fuse of sequence of operations. Intended only for
 /// testing.
 struct TestLinalgTileAndFuseSequencePass