[Mlir-commits] [mlir] [mlir][arith] Check for valid IR in BitcastOp::fold. (PR #100743)

[Mehdi Amini]

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@@ -0,0 +1,46 @@
+//===- ArithOpsFoldersTest.cpp - unit tests for arith op folders ----------===//
+//
+// 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/Arith/IR/Arith.h"
+#include "mlir/IR/BuiltinOps.h"
+#include "mlir/IR/Verifier.h"
+#include "gtest/gtest.h"
+
+using namespace mlir;
+
+namespace {
+// Tests a regression that made `BitcastOp::fold` crash on invalid input IR, see
+// #100743,
+TEST(BitcastOpTest, FoldInteger) {
+  MLIRContext context;
+  context.loadDialect<arith::ArithDialect>();
+  auto loc = UnknownLoc::get(&context);
+  auto module = ModuleOp::create(loc);
+  OpBuilder builder(module.getBodyRegion());
+  Value i32Val = builder.create<arith::ConstantOp>(
+      loc, builder.getI32Type(), builder.getI32IntegerAttr(0));
+  // This would create an invalid op: `bitcast` can't cast different bitwidths.
+  builder.createOrFold<arith::BitcastOp>(loc, builder.getI64Type(), i32Val);
+  ASSERT_TRUE(failed(verify(module)));
+}
+
+// Tests a regression that made `BitcastOp::fold` crash on invalid input IR, see
+// #100743,
+TEST(BitcastOpTest, FoldFloat) {
+  MLIRContext context;
+  context.loadDialect<arith::ArithDialect>();
+  auto loc = UnknownLoc::get(&context);
+  auto module = ModuleOp::create(loc);
+  OpBuilder builder(module.getBodyRegion());
+  Value f32Val = builder.create<arith::ConstantOp>(loc, builder.getF32Type(),
+                                                   builder.getF32FloatAttr(0));
+  // This would create an invalid op: `bitcast` can't cast different bitwidths.
+  builder.createOrFold<arith::BitcastOp>(loc, builder.getF64Type(), f32Val);
+  ASSERT_TRUE(failed(verify(module)));
+}
+} // namespace
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joker-eph wrote:

I don't expect C++ unit-tests for this kind of thing.

https://github.com/llvm/llvm-project/pull/100743