[MLIR] Add `print-ir` pass for debugging purposes

[frgossen]

Summary

Add pass to print the entire IR on the debug stream.
This is meant for debugging purposes to inspect the IR at a specific point in the pipeline.

[frgossen]

Fix Cmake file

[frgossen]

Rebase

[frgossen]

Rebase

[pifon2a]

Is it equivalent to mlir-print-ir-after=pass-name ? https://mlir.llvm.org/docs/PassManagement/#ir-printing

[frgossen]

mlir-print-ir-after=pass-name is easy enough to use from the opt tools. However, I could not find an easy way to set that programmatically (or pass the flag through the tests)

[pifon2a]

mlir/lib/Transforms/DumpIR.cpp

18 ↗

(On Diff #501220)

PrintIR?

[frgossen]

Address comments

[pifon2a]

mlir/lib/Transforms/CMakeLists.txt

7

nit: sort

[frgossen]

.

[frgossen]

.

mlir/include/mlir/Transforms/Passes.h

createCanonicalizerPass(const GreedyRewriteConfig &config,
                         ArrayRef<std::string> enabledPatterns = std::nullopt);
 
 /// Creates a pass to perform control-flow sinking.
 std::unique_ptr<Pass> createControlFlowSinkPass();
 
 /// Creates a pass to perform common sub expression elimination.
 std::unique_ptr<Pass> createCSEPass();
 
+/// Creates a pass to print IR on the debug stream.
+std::unique_ptr<Pass> createPrintIRPass();
+
 /// Creates a pass that generates IR to verify ops at runtime.
 std::unique_ptr<Pass> createGenerateRuntimeVerificationPass();
 
 /// Creates a loop invariant code motion pass that hoists loop invariant
 /// instructions out of the loop.
 std::unique_ptr<Pass> createLoopInvariantCodeMotionPass();
 
 /// Creates a pass to strip debug information from a function.

mlir/include/mlir/Transforms/Passes.td

def CSE : Pass<"cse"> {
   }];
   let constructor = "mlir::createCSEPass()";
   let statistics = [
     Statistic<"numCSE", "num-cse'd", "Number of operations CSE'd">,
     Statistic<"numDCE", "num-dce'd", "Number of operations DCE'd">
   ];
 }
 
+def PrintIRPass : Pass<"print-ir"> {
+  let summary = "Print IR on the debug stream";
+  let description = [{
+    Print the entire IR on the debug stream. This is meant for debugging
+    purposes to inspect the IR at a specific point in the pipeline.
+  }];
+  let constructor = "mlir::createPrintIRPass()";
+}
+
 def GenerateRuntimeVerification : Pass<"generate-runtime-verification"> {
   let summary = "Generate additional runtime op verification checks";
   let description = [{
     This pass generates op-specific runtime checks using the
     `RuntimeVerifiableOpInterface`. It can be run for debugging purposes after
     passes that are suspected to introduce faulty IR.
   }];
   let constructor = "mlir::createGenerateRuntimeVerificationPass()";

mlir/lib/Transforms/CMakeLists.txt

 add_subdirectory(Utils)
 
 add_mlir_library(MLIRTransforms
   Canonicalizer.cpp
   ControlFlowSink.cpp
   CSE.cpp
   GenerateRuntimeVerification.cpp
   Inliner.cpp
   LocationSnapshot.cpp
   LoopInvariantCodeMotion.cpp
   OpStats.cpp
+  PrintIR.cpp
   SCCP.cpp
   StripDebugInfo.cpp
   SymbolDCE.cpp
   SymbolPrivatize.cpp
   TopologicalSort.cpp
   ViewOpGraph.cpp
 
   ADDITIONAL_HEADER_DIRS

mlir/lib/Transforms/PrintIR.cpp

+//===- PrintIR.cpp - Pass to dump IR on debug stream ----------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Pass/Pass.h"
+
+namespace mlir {
+namespace {
+
+#define GEN_PASS_DEF_PRINTIRPASS
+#include "mlir/Transforms/Passes.h.inc"
+
+struct PrintIRPass : public impl::PrintIRPassBase<PrintIRPass> {
+  PrintIRPass() = default;
+
+  void runOnOperation() override { getOperation()->dump(); }
+};
+
+} // namespace
+
+std::unique_ptr<Pass> createPrintIRPass() {
+  return std::make_unique<PrintIRPass>();
+}
+
+} // namespace mlir
 No newline at end of file