From 103934a9a6b249241335d2bdea4afc868af5494b Mon Sep 17 00:00:00 2001 From: Matthias Springer Date: Wed, 6 Dec 2023 12:42:33 +0900 Subject: [PATCH] [mlir][SCF] Fix invalid IR in `ParallelOpSingleOrZeroIterationDimsFolder` pattern `ParallelOpSingleOrZeroIterationDimsFolder` used to produce invalid IR: ``` within split at mlir/test/Dialect/SCF/canonicalize.mlir:1 offset :11:3: error: 'scf.parallel' op expects region #0 to have 0 or 1 blocks scf.parallel (%i0, %i1, %i2) = (%c0, %c3, %c7) to (%c1, %c6, %c10) step (%c1, %c2, %c3) { ^ within split at mlir/test/Dialect/SCF/canonicalize.mlir:1 offset :11:3: note: see current operation: "scf.parallel"(%4, %5, %3) <{operandSegmentSizes = array}> ({ ^bb0(%arg1: index): "memref.store"(%0, %arg0, %1, %arg1, %6) : (i32, memref, index, index, index) -> () "scf.yield"() : () -> () ^bb1(%8: index): // no predecessors "scf.yield"() : () -> () }) : (index, index, index) -> () ``` Together with #74551, this commit fixes `mlir/test/Dialect/SCF/canonicalize.mlir` when verifying the IR after each pattern application (#74270). --- mlir/lib/Dialect/SCF/IR/SCF.cpp | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mlir/lib/Dialect/SCF/IR/SCF.cpp b/mlir/lib/Dialect/SCF/IR/SCF.cpp index 3b55704c4ea07..2e7382160f8eb 100644 --- a/mlir/lib/Dialect/SCF/IR/SCF.cpp +++ b/mlir/lib/Dialect/SCF/IR/SCF.cpp @@ -3040,6 +3040,8 @@ struct ParallelOpSingleOrZeroIterationDimsFolder auto newOp = rewriter.create(op.getLoc(), newLowerBounds, newUpperBounds, newSteps, op.getInitVals(), nullptr); + // Erase the empty block that was inserted by the builder. + rewriter.eraseBlock(newOp.getBody()); // Clone the loop body and remap the block arguments of the collapsed loops // (inlining does not support a cancellable block argument mapping). rewriter.cloneRegionBefore(op.getRegion(), newOp.getRegion(),