[Mlir-commits] [mlir] [mlir][Arith] Let integer range narrowing handle negative values (PR #119642)

[Ivan Butygin]

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@@ -425,19 +437,24 @@ struct NarrowCmpI final : OpRewritePattern<arith::CmpIOp> {
 /// Fold index_cast(index_cast(%arg: i8, index), i8) -> %arg
 /// This pattern assumes all passed `targetBitwidths` are not wider than index
 /// type.
-struct FoldIndexCastChain final : OpRewritePattern<arith::IndexCastUIOp> {
+template <typename CastOp>
+struct FoldIndexCastChain final : OpRewritePattern<CastOp> {
   FoldIndexCastChain(MLIRContext *context, ArrayRef<unsigned> target)
-      : OpRewritePattern(context), targetBitwidths(target) {}
+      : OpRewritePattern<CastOp>(context), targetBitwidths(target) {}
 
-  LogicalResult matchAndRewrite(arith::IndexCastUIOp op,
+  LogicalResult matchAndRewrite(CastOp op,
                                 PatternRewriter &rewriter) const override {
-    auto srcOp = op.getIn().getDefiningOp<arith::IndexCastUIOp>();
+    auto srcOp = op.getIn().template getDefiningOp<CastOp>();
     if (!srcOp)
-      return failure();
+      return rewriter.notifyMatchFailure(op, "doesn't come from an index cast");
+    ;
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Hardcode84 wrote:

nit: extra `;`

https://github.com/llvm/llvm-project/pull/119642