[Mlir-commits] [mlir] [mlir][Transforms] Fix build after #116524 (part 2) (PR #121662)

[Matthias Springer]

https://github.com/matthias-springer created https://github.com/llvm/llvm-project/pull/121662

Since #116524, an integration test started to become flaky (failure rate ~15%).

```
bin/mlir-opt mlir/test/Integration/Dialect/SparseTensor/CPU/sparse_block_matmul.mlir --sparsifier="enable-arm-sve=true enable-runtime-library=false vl=2 reassociate-fp-reductions=true enable-index-optimizations=true" | mlir-cpu-runner --march=aarch64 --mattr="+sve" -e main -entry-point-result=void -shared-libs=./lib/libmlir_runner_utils.so,./lib/libmlir_c_runner_utils.so | bin/FileCheck mlir/test/Integration/Dialect/SparseTensor/CPU/sparse_block_matmul.mlir
# executed command: bin/mlir-opt mlir/test/Integration/Dialect/SparseTensor/CPU/sparse_block_matmul.mlir '--sparsifier=enable-arm-sve=true enable-runtime-library=false vl=2 reassociate-fp-reductions=true enable-index-optimizations=true'
# .---command stderr------------
# | mlir/test/Integration/Dialect/SparseTensor/CPU/sparse_block_matmul.mlir:71:10: error: null operand found
# |     %0 = linalg.generic #trait_mul
# |          ^
# | mlir/test/Integration/Dialect/SparseTensor/CPU/sparse_block_matmul.mlir:71:10: note: see current operation: %70 = "arith.mulf"(<<NULL VALUE>>, %69) <{fastmath = #arith.fastmath<none>}> : (<<NULL TYPE>>, vector<[2]xf64>) -> vector<[2]xf64>
# `-----------------------------
# error: command failed with exit status: 1
```

I traced the issue back to the `DenseMap<ValueVector, ValueVector, ValueVectorMapInfo> mapping;` data structure: previously, some `mapping.erase(foo)` calls were unsuccessful (returning `false`), even though the `mapping` contains `foo` as a key.


>From 01d6bd1684a4337671da17b63cf496b2316d0280 Mon Sep 17 00:00:00 2001
From: Matthias Springer <mspringer at nvidia.com>
Date: Sat, 4 Jan 2025 21:20:14 +0100
Subject: [PATCH] [mlir][Transforms] Fix build after #116524 (part 2)

---
 mlir/lib/Transforms/Utils/DialectConversion.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mlir/lib/Transforms/Utils/DialectConversion.cpp b/mlir/lib/Transforms/Utils/DialectConversion.cpp
index 0e577d2d39de3d..48b8c727a78285 100644
--- a/mlir/lib/Transforms/Utils/DialectConversion.cpp
+++ b/mlir/lib/Transforms/Utils/DialectConversion.cpp
@@ -103,8 +103,8 @@ namespace {
 
 /// Helper class to make it possible to use `ValueVector` as a key in DenseMap.
 struct ValueVectorMapInfo {
-  static ValueVector getEmptyKey() { return ValueVector{}; }
-  static ValueVector getTombstoneKey() { return ValueVector{}; }
+  static ValueVector getEmptyKey() { return ValueVector{Value()}; }
+  static ValueVector getTombstoneKey() { return ValueVector{Value(), Value()}; }
   static ::llvm::hash_code getHashValue(const ValueVector &val) {
     return ::llvm::hash_combine_range(val.begin(), val.end());
   }