Refactor `mlir-translate` to extract the `main()` logic in a helper on the model of `MlirOptMain()` (NFC)

[mehdi_amini]

Minor fix

[rriddle]

mlir/include/mlir/Translation.h

98

The naming style here looks off.

mlir/lib/Translation/Translation.cpp

19

I'd say this, and likely a few others, could be trimmed.

198–199

Merge the else and the if?

[mehdi_amini]

Address comments

[bondhugula]

mlir/include/mlir/Translation.h

96

ToolName -> toolName in backticks.

96

Can you rephrase to say what it does: "Translates ...", and then what you have here.

[mehdi_amini]

Thanks, I addressed in https://github.com/llvm/llvm-project/commit/50927f3191f908142201ccc50962537bf9d96bda

mlir/include/mlir/Translation.h

 
 namespace llvm {
 class MemoryBuffer;
 class SourceMgr;
 class StringRef;
 } // namespace llvm
 
 namespace mlir {
+class DialectRegistry;
 struct LogicalResult;
 class MLIRContext;
 class ModuleOp;
 class OwningModuleRef;
 
 /// Interface of the function that translates the sources managed by `sourceMgr`
 /// to MLIR. The source manager has at least one buffer. The implementation
 /// should create a new MLIR ModuleOp in the given context and return a pointer

 
 /// A command line parser for translation functions.
 struct TranslationParser : public llvm::cl::parser<const TranslateFunction *> {
   TranslationParser(llvm::cl::Option &opt);
 
   void printOptionInfo(const llvm::cl::Option &o,
                        size_t globalWidth) const override;
 };
+
+/// Implementation for tools like `mlir-translate`. ToolName is used for the
+/// header displayed by `--help`.
+LogicalResult mlirTranslateMain(int argc, char **argv,
+                                llvm::StringRef toolName);
+
 } // namespace mlir
 
 #endif // MLIR_TRANSLATION_H

mlir/lib/Translation/Translation.cpp

 //===- Translation.cpp - Translation registry -----------------------------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 //
 // Definitions of the translation registry.
 //
 //===----------------------------------------------------------------------===//
 
 #include "mlir/Translation.h"
+#include "mlir/IR/AsmState.h"
 #include "mlir/IR/Module.h"
 #include "mlir/IR/Verifier.h"
 #include "mlir/Parser.h"
-#include "mlir/Support/LLVM.h"
+#include "mlir/Support/FileUtilities.h"
+#include "mlir/Support/ToolUtilities.h"
+#include "llvm/Support/InitLLVM.h"
 #include "llvm/Support/SourceMgr.h"
+#include "llvm/Support/ToolOutputFile.h"
 
 using namespace mlir;
 
 //===----------------------------------------------------------------------===//
 // Translation Registry
 //===----------------------------------------------------------------------===//
 
 /// Get the mutable static map between registered file-to-file MLIR translations
void TranslationParser::printOptionInfo(const llvm::cl::Option &o,
   TranslationParser *tp = const_cast<TranslationParser *>(this);
   llvm::array_pod_sort(tp->Values.begin(), tp->Values.end(),
                        [](const TranslationParser::OptionInfo *lhs,
                           const TranslationParser::OptionInfo *rhs) {
                          return lhs->Name.compare(rhs->Name);
                        });
   llvm::cl::parser<const TranslateFunction *>::printOptionInfo(o, globalWidth);
 }
+
+LogicalResult mlir::mlirTranslateMain(int argc, char **argv,
+                                      llvm::StringRef toolName) {
+
+  static llvm::cl::opt<std::string> inputFilename(
+      llvm::cl::Positional, llvm::cl::desc("<input file>"),
+      llvm::cl::init("-"));
+
+  static llvm::cl::opt<std::string> outputFilename(
+      "o", llvm::cl::desc("Output filename"), llvm::cl::value_desc("filename"),
+      llvm::cl::init("-"));
+
+  static llvm::cl::opt<bool> splitInputFile(
+      "split-input-file",
+      llvm::cl::desc("Split the input file into pieces and "
+                     "process each chunk independently"),
+      llvm::cl::init(false));
+
+  static llvm::cl::opt<bool> verifyDiagnostics(
+      "verify-diagnostics",
+      llvm::cl::desc("Check that emitted diagnostics match "
+                     "expected-* lines on the corresponding line"),
+      llvm::cl::init(false));
+
+  llvm::InitLLVM y(argc, argv);
+
+  // Add flags for all the registered translations.
+  llvm::cl::opt<const TranslateFunction *, false, TranslationParser>
+      translationRequested("", llvm::cl::desc("Translation to perform"),
+                           llvm::cl::Required);
+  registerAsmPrinterCLOptions();
+  registerMLIRContextCLOptions();
+  llvm::cl::ParseCommandLineOptions(argc, argv, "MLIR translation driver\n");
+
+  std::string errorMessage;
+  auto input = openInputFile(inputFilename, &errorMessage);
+  if (!input) {
+    llvm::errs() << errorMessage << "\n";
+    return failure();
+  }
+
+  auto output = openOutputFile(outputFilename, &errorMessage);
+  if (!output) {
+    llvm::errs() << errorMessage << "\n";
+    return failure();
+  }
+
+  // Processes the memory buffer with a new MLIRContext.
+  auto processBuffer = [&](std::unique_ptr<llvm::MemoryBuffer> ownedBuffer,
+                           raw_ostream &os) {
+    MLIRContext context;
+    context.printOpOnDiagnostic(!verifyDiagnostics);
+    llvm::SourceMgr sourceMgr;
+    sourceMgr.AddNewSourceBuffer(std::move(ownedBuffer), llvm::SMLoc());
+
+    if (!verifyDiagnostics) {
+      SourceMgrDiagnosticHandler sourceMgrHandler(sourceMgr, &context);
+      return (*translationRequested)(sourceMgr, os, &context);
+    }
+
+    // In the diagnostic verification flow, we ignore whether the translation
+    // failed (in most cases, it is expected to fail). Instead, we check if the
+    // diagnostics were produced as expected.
+    SourceMgrDiagnosticVerifierHandler sourceMgrHandler(sourceMgr, &context);
+    (*translationRequested)(sourceMgr, os, &context);
+    return sourceMgrHandler.verify();
+  };
+
+  if (splitInputFile) {
+    if (failed(splitAndProcessBuffer(std::move(input), processBuffer,
+                                     output->os())))
+      return failure();
+  } else if (failed(processBuffer(std::move(input), output->os()))) {
+    return failure();
+  }
+
+  output->keep();
+  return success();
+}

mlir/tools/mlir-translate/mlir-translate.cpp

 //===- mlir-translate.cpp - MLIR Translate Driver -------------------------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 //
 // This is a command line utility that translates a file from/to MLIR using one
 // of the registered translations.
 //
 //===----------------------------------------------------------------------===//
 
-#include "mlir/IR/AsmState.h"
-#include "mlir/IR/Diagnostics.h"
-#include "mlir/IR/MLIRContext.h"
 #include "mlir/InitAllDialects.h"
 #include "mlir/InitAllTranslations.h"
-#include "mlir/Support/FileUtilities.h"
-#include "mlir/Support/LogicalResult.h"
-#include "mlir/Support/ToolUtilities.h"
 #include "mlir/Translation.h"
-#include "llvm/Support/InitLLVM.h"
-#include "llvm/Support/MemoryBuffer.h"
-#include "llvm/Support/SourceMgr.h"
-#include "llvm/Support/ToolOutputFile.h"
 
 using namespace mlir;
 
-static llvm::cl::opt<std::string> inputFilename(llvm::cl::Positional,
-                                                llvm::cl::desc("<input file>"),
-                                                llvm::cl::init("-"));
-
-static llvm::cl::opt<std::string>
-    outputFilename("o", llvm::cl::desc("Output filename"),
-                   llvm::cl::value_desc("filename"), llvm::cl::init("-"));
-
-static llvm::cl::opt<bool>
-    splitInputFile("split-input-file",
-                   llvm::cl::desc("Split the input file into pieces and "
-                                  "process each chunk independently"),
-                   llvm::cl::init(false));
-
-static llvm::cl::opt<bool> verifyDiagnostics(
-    "verify-diagnostics",
-    llvm::cl::desc("Check that emitted diagnostics match "
-                   "expected-* lines on the corresponding line"),
-    llvm::cl::init(false));
 
 namespace mlir {
 // Defined in the test directory, no public header.
 void registerTestRoundtripSPIRV();
 void registerTestRoundtripDebugSPIRV();
 } // namespace mlir
 
 static void registerTestTranslations() {
   registerTestRoundtripSPIRV();
   registerTestRoundtripDebugSPIRV();
 }
 
 int main(int argc, char **argv) {
-  registerAllDialects();
   registerAllTranslations();
   registerTestTranslations();
-  llvm::InitLLVM y(argc, argv);
-
-  // Add flags for all the registered translations.
-  llvm::cl::opt<const TranslateFunction *, false, TranslationParser>
-      translationRequested("", llvm::cl::desc("Translation to perform"),
-                           llvm::cl::Required);
-  registerAsmPrinterCLOptions();
-  registerMLIRContextCLOptions();
-  llvm::cl::ParseCommandLineOptions(argc, argv, "MLIR translation driver\n");
-
-  std::string errorMessage;
-  auto input = openInputFile(inputFilename, &errorMessage);
-  if (!input) {
-    llvm::errs() << errorMessage << "\n";
-    return 1;
-  }
-
-  auto output = openOutputFile(outputFilename, &errorMessage);
-  if (!output) {
-    llvm::errs() << errorMessage << "\n";
-    return 1;
-  }
-
-  // Processes the memory buffer with a new MLIRContext.
-  auto processBuffer = [&](std::unique_ptr<llvm::MemoryBuffer> ownedBuffer,
-                           raw_ostream &os) {
-    MLIRContext context(false);
-    registerAllDialects(&context);
-    context.allowUnregisteredDialects();
-    context.printOpOnDiagnostic(!verifyDiagnostics);
-    llvm::SourceMgr sourceMgr;
-    sourceMgr.AddNewSourceBuffer(std::move(ownedBuffer), llvm::SMLoc());
-
-    if (!verifyDiagnostics) {
-      SourceMgrDiagnosticHandler sourceMgrHandler(sourceMgr, &context);
-      return (*translationRequested)(sourceMgr, os, &context);
-    }
-
-    // In the diagnostic verification flow, we ignore whether the translation
-    // failed (in most cases, it is expected to fail). Instead, we check if the
-    // diagnostics were produced as expected.
-    SourceMgrDiagnosticVerifierHandler sourceMgrHandler(sourceMgr, &context);
-    (*translationRequested)(sourceMgr, os, &context);
-    return sourceMgrHandler.verify();
-  };
-
-  if (splitInputFile) {
-    if (failed(splitAndProcessBuffer(std::move(input), processBuffer,
-                                     output->os())))
-      return 1;
-  } else {
-    if (failed(processBuffer(std::move(input), output->os())))
-      return 1;
-  }
-
-  output->keep();
-  return 0;
+  // TODO: remove the global dialect registry
+  registerAllDialects();
+  return failed(mlirTranslateMain(argc, argv, "MLIR Translation Testing Tool"));
 }