[Mlir-commits] [mlir] [mlir] Add pass to add comdat to all linkonce functions (PR #65270)

[Mehdi Amini]

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@@ -0,0 +1,56 @@
+//===- AddComdats.cpp - Add comdats to linkonce functions -----------------===//
+//
+// 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/Dialect/LLVMIR/Transforms/AddComdats.h"
+#include "mlir/Dialect/LLVMIR/LLVMDialect.h"
+#include "mlir/Pass/Pass.h"
+
+namespace mlir {
+namespace LLVM {
+#define GEN_PASS_DEF_LLVMADDCOMDATS
+#include "mlir/Dialect/LLVMIR/Transforms/Passes.h.inc"
+} // namespace LLVM
+} // namespace mlir
+
+using namespace mlir;
+
+static void addComdat(LLVM::LLVMFuncOp &op, OpBuilder &builder,
+                      ModuleOp &module) {
+  const char *comdatName = "__llvm_comdat";
+  mlir::LLVM::ComdatOp comdatOp =
+      module.lookupSymbol<mlir::LLVM::ComdatOp>(comdatName);
+  if (!comdatOp) {
+    PatternRewriter::InsertionGuard guard(builder);
+    builder.setInsertionPointToStart(module.getBody());
+    comdatOp =
+        builder.create<mlir::LLVM::ComdatOp>(module.getLoc(), comdatName);
+  }
+
+  PatternRewriter::InsertionGuard guard(builder);
+  builder.setInsertionPointToStart(&comdatOp.getBody().back());
+  auto selectorOp = builder.create<mlir::LLVM::ComdatSelectorOp>(
+      comdatOp.getLoc(), op.getSymName(), mlir::LLVM::comdat::Comdat::Any);
+  op.setComdatAttr(mlir::SymbolRefAttr::get(
+      builder.getContext(), comdatName,
+      mlir::FlatSymbolRefAttr::get(selectorOp.getSymNameAttr())));
+}
+
+namespace {
+struct AddComdatsPass : public LLVM::impl::LLVMAddComdatsBase<AddComdatsPass> {
+  void runOnOperation() override {
+    OpBuilder builder{&getContext()};
+    ModuleOp mod = getOperation();
+    mod.walk([&](LLVM::LLVMFuncOp op) {
----------------
joker-eph wrote:

The walk is recursive here, we should just iterate: `for (auto op = mod.getOperations<LLVM::LLVMFuncOp>())`

https://github.com/llvm/llvm-project/pull/65270