[clang] [CIR] Add cir-translate and cir-lsp-server tools (PR #131181)

[Morris Hafner via cfe-commits]

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@@ -0,0 +1,166 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Converts CIR directly to LLVM IR, similar to mlir-translate or LLVM llc.
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Dialect/DLTI/DLTI.h"
+#include "mlir/Dialect/Func/IR/FuncOps.h"
+#include "mlir/Dialect/LLVMIR/LLVMDialect.h"
+#include "mlir/IR/BuiltinOps.h"
+#include "mlir/IR/MLIRContext.h"
+#include "mlir/InitAllTranslations.h"
+#include "mlir/Support/LogicalResult.h"
+#include "mlir/Target/LLVMIR/Dialect/All.h"
+#include "mlir/Target/LLVMIR/Import.h"
+#include "mlir/Tools/mlir-translate/MlirTranslateMain.h"
+#include "mlir/Tools/mlir-translate/Translation.h"
+
+#include "llvm/IR/Module.h"
+#include "llvm/TargetParser/Host.h"
+
+#include "clang/Basic/TargetInfo.h"
+#include "clang/CIR/Dialect/IR/CIRDialect.h"
+#include "clang/CIR/Dialect/Passes.h"
+#include "clang/CIR/LowerToLLVM.h"
+#include "clang/CIR/MissingFeatures.h"
+
+namespace cir {
+namespace direct {
+extern void registerCIRDialectTranslation(mlir::DialectRegistry &registry);
+} // namespace direct
+
+namespace {
+
+/// The goal of this option is to ensure that the triple and data layout specs
+/// are always available in the ClangIR module. With this requirement met, the
+/// behavior of this option is designed to be as intuitive as possible, as shown
+/// in the table below:
+///
+/// +--------+--------+-------------+-----------------+-----------------------+
+/// | Option | Triple | Data Layout | Behavior Triple | Behavior Data Layout  |
+/// +========+========+=============+=================+=======================+
+/// | T      | T      | T           | Overwrite       | Derive from triple    |
+/// | T      | T      | F           | Overwrite       | Derive from triple    |
+/// | T      | F      | T           | Overwrite       | Derive from triple    |
+/// | T      | F      | F           | Overwrite       | Derive from triple    |
+/// | F      | T      | T           |                 |                       |
+/// | F      | T      | F           |                 | Derive from triple    |
+/// | F      | F      | T           | Set default     | Derive from triple    |
+/// | F      | F      | F           | Set default     | Derive from triple    |
+/// +--------+--------+-------------+-----------------+-----------------------+
+llvm::cl::opt<std::string>
+    targetTripleOption("target",
+                       llvm::cl::desc("Specify a default target triple when "
+                                      "it's not available in the module"),
+                       llvm::cl::init(""));
+
+std::string prepareCIRModuleTriple(mlir::ModuleOp mod) {
+  std::string triple = targetTripleOption;
+
+  // Treat "" as the default target machine.
+  if (triple.empty()) {
+    triple = llvm::sys::getDefaultTargetTriple();
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mmha wrote:

This differs from the incubator which defaults to `"x86_64-unknown-linux-gnu"`.

https://github.com/llvm/llvm-project/pull/131181