llvm-project

40e85fca - [MLIR][XeGPU][VectorToXeGPU] Fix transfer_read/write cases with non-contiguous memrefs (#158126)

[MLIR][XeGPU][VectorToXeGPU] Fix transfer_read/write cases with non-contiguous memrefs (#158126) This PR fixes a case where a source memref in `vector.transfer_read/write` is not contiguous, which violates the `memref.collapse_shape` semantic that is used in the lowering. <details><summary>An example of a failing test</summary> ```mlir gpu.module @xevm_module { gpu.func @load_from_subview(%source: memref<4096x4096xf16>, %off1: index, %off2: index) -> vector<8xf16> { %c0 = arith.constant 0.0 : f16 %subview = memref.subview %source[%off1, %off2] [256, 256] [1, 1] : memref<4096x4096xf16> to memref<256x256xf16, strided<[4096, 1], offset: ?>> %0 = vector.transfer_read %subview[%off2, %off2], %c0 {in_bounds = [true]} : memref<256x256xf16, strided<[4096, 1], offset: ?>>, vector<8xf16> gpu.return %0 : vector<8xf16> } } ``` Fails with: ``` /home/user/llvm/mlir/test/Conversion/VectorToXeGPU/transfer-read-to-xegpu.mlir:404:8: error: 'memref.collapse_shape' op invalid source layout map or collapsing non-contiguous dims %0 = vector.transfer_read %subview[%off2, %off2], %c0 ^ /home/user/llvm/mlir/test/Conversion/VectorToXeGPU/transfer-read-to-xegpu.mlir:404:8: note: see current operation: %8 = "memref.collapse_shape"(%2) <{reassociation = [[0, 1]]}> : (memref<256x256xf16, strided<[4096, 1], offset: ?>>) -> memref<65536xf16> ``` </details> A suggestion was to replace `memref.collapse_shape` with `memref.extract_aligned_pointer_as_index` which is done in this PR. Since `extract_aligned_pointer` applied to a subview returns an original pointer without subview offsets, this PR also adds a logic to use an offset obtained from `memref.extract_strided_metadata` in `baseOffset` calculation in `computeOffsets`. --------- Signed-off-by: dchigarev <dmitry.chigarev@intel.com>