fe8a62c463
Fix obvious bug in AffineMap::replace for the case of zero result maps. Extend/complete inferExprsFromList to work with empty expression lists.
676 lines
28 KiB
C++
676 lines
28 KiB
C++
//===- VectorTransferSplitRewritePatterns.cpp - Transfer Split Rewrites ---===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements target-independent patterns to rewrite a vector.transfer
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// op into a fully in-bounds part and a partial part.
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//
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//===----------------------------------------------------------------------===//
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#include <optional>
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#include <type_traits>
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#include "mlir/Dialect/Affine/IR/AffineOps.h"
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#include "mlir/Dialect/Arith/IR/Arith.h"
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#include "mlir/Dialect/Linalg/IR/Linalg.h"
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#include "mlir/Dialect/MemRef/IR/MemRef.h"
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#include "mlir/Dialect/SCF/IR/SCF.h"
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#include "mlir/Dialect/Utils/StructuredOpsUtils.h"
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#include "mlir/Dialect/Vector/Transforms/VectorTransforms.h"
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#include "mlir/IR/Matchers.h"
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#include "mlir/IR/PatternMatch.h"
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#include "mlir/Interfaces/VectorInterfaces.h"
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#include "llvm/ADT/DenseSet.h"
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#include "llvm/ADT/MapVector.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/raw_ostream.h"
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#define DEBUG_TYPE "vector-transfer-split"
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using namespace mlir;
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using namespace mlir::vector;
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/// Build the condition to ensure that a particular VectorTransferOpInterface
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/// is in-bounds.
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static Value createInBoundsCond(RewriterBase &b,
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VectorTransferOpInterface xferOp) {
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assert(xferOp.getPermutationMap().isMinorIdentity() &&
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"Expected minor identity map");
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Value inBoundsCond;
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xferOp.zipResultAndIndexing([&](int64_t resultIdx, int64_t indicesIdx) {
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// Zip over the resulting vector shape and memref indices.
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// If the dimension is known to be in-bounds, it does not participate in
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// the construction of `inBoundsCond`.
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if (xferOp.isDimInBounds(resultIdx))
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return;
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// Fold or create the check that `index + vector_size` <= `memref_size`.
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Location loc = xferOp.getLoc();
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int64_t vectorSize = xferOp.getVectorType().getDimSize(resultIdx);
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OpFoldResult sum = affine::makeComposedFoldedAffineApply(
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b, loc, b.getAffineDimExpr(0) + b.getAffineConstantExpr(vectorSize),
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{xferOp.getIndices()[indicesIdx]});
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OpFoldResult dimSz =
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memref::getMixedSize(b, loc, xferOp.getSource(), indicesIdx);
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auto maybeCstSum = getConstantIntValue(sum);
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auto maybeCstDimSz = getConstantIntValue(dimSz);
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if (maybeCstSum && maybeCstDimSz && *maybeCstSum <= *maybeCstDimSz)
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return;
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Value cond =
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b.create<arith::CmpIOp>(loc, arith::CmpIPredicate::sle,
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getValueOrCreateConstantIndexOp(b, loc, sum),
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getValueOrCreateConstantIndexOp(b, loc, dimSz));
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// Conjunction over all dims for which we are in-bounds.
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if (inBoundsCond)
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inBoundsCond = b.create<arith::AndIOp>(loc, inBoundsCond, cond);
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else
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inBoundsCond = cond;
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});
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return inBoundsCond;
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}
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/// Split a vector.transfer operation into an in-bounds (i.e., no out-of-bounds
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/// masking) fast path and a slow path.
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/// If `ifOp` is not null and the result is `success, the `ifOp` points to the
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/// newly created conditional upon function return.
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/// To accommodate for the fact that the original vector.transfer indexing may
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/// be arbitrary and the slow path indexes @[0...0] in the temporary buffer, the
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/// scf.if op returns a view and values of type index.
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/// At this time, only vector.transfer_read case is implemented.
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///
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/// Example (a 2-D vector.transfer_read):
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/// ```
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/// %1 = vector.transfer_read %0[...], %pad : memref<A...>, vector<...>
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/// ```
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/// is transformed into:
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/// ```
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/// %1:3 = scf.if (%inBounds) {
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/// // fast path, direct cast
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/// memref.cast %A: memref<A...> to compatibleMemRefType
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/// scf.yield %view : compatibleMemRefType, index, index
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/// } else {
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/// // slow path, not in-bounds vector.transfer or linalg.copy.
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/// memref.cast %alloc: memref<B...> to compatibleMemRefType
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/// scf.yield %4 : compatibleMemRefType, index, index
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// }
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/// %0 = vector.transfer_read %1#0[%1#1, %1#2] {in_bounds = [true ... true]}
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/// ```
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/// where `alloc` is a top of the function alloca'ed buffer of one vector.
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///
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/// Preconditions:
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/// 1. `xferOp.getPermutationMap()` must be a minor identity map
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/// 2. the rank of the `xferOp.memref()` and the rank of the
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/// `xferOp.getVector()` must be equal. This will be relaxed in the future
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/// but requires rank-reducing subviews.
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static LogicalResult
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splitFullAndPartialTransferPrecondition(VectorTransferOpInterface xferOp) {
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// TODO: support 0-d corner case.
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if (xferOp.getTransferRank() == 0)
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return failure();
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// TODO: expand support to these 2 cases.
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if (!xferOp.getPermutationMap().isMinorIdentity())
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return failure();
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// Must have some out-of-bounds dimension to be a candidate for splitting.
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if (!xferOp.hasOutOfBoundsDim())
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return failure();
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// Don't split transfer operations directly under IfOp, this avoids applying
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// the pattern recursively.
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// TODO: improve the filtering condition to make it more applicable.
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if (isa<scf::IfOp>(xferOp->getParentOp()))
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return failure();
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return success();
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}
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/// Given two MemRefTypes `aT` and `bT`, return a MemRefType to which both can
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/// be cast. If the MemRefTypes don't have the same rank or are not strided,
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/// return null; otherwise:
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/// 1. if `aT` and `bT` are cast-compatible, return `aT`.
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/// 2. else return a new MemRefType obtained by iterating over the shape and
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/// strides and:
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/// a. keeping the ones that are static and equal across `aT` and `bT`.
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/// b. using a dynamic shape and/or stride for the dimensions that don't
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/// agree.
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static MemRefType getCastCompatibleMemRefType(MemRefType aT, MemRefType bT) {
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if (memref::CastOp::areCastCompatible(aT, bT))
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return aT;
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if (aT.getRank() != bT.getRank())
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return MemRefType();
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int64_t aOffset, bOffset;
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SmallVector<int64_t, 4> aStrides, bStrides;
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if (failed(getStridesAndOffset(aT, aStrides, aOffset)) ||
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failed(getStridesAndOffset(bT, bStrides, bOffset)) ||
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aStrides.size() != bStrides.size())
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return MemRefType();
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ArrayRef<int64_t> aShape = aT.getShape(), bShape = bT.getShape();
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int64_t resOffset;
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SmallVector<int64_t, 4> resShape(aT.getRank(), 0),
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resStrides(bT.getRank(), 0);
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for (int64_t idx = 0, e = aT.getRank(); idx < e; ++idx) {
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resShape[idx] =
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(aShape[idx] == bShape[idx]) ? aShape[idx] : ShapedType::kDynamic;
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resStrides[idx] =
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(aStrides[idx] == bStrides[idx]) ? aStrides[idx] : ShapedType::kDynamic;
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}
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resOffset = (aOffset == bOffset) ? aOffset : ShapedType::kDynamic;
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return MemRefType::get(
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resShape, aT.getElementType(),
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StridedLayoutAttr::get(aT.getContext(), resOffset, resStrides));
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}
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/// Casts the given memref to a compatible memref type. If the source memref has
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/// a different address space than the target type, a `memref.memory_space_cast`
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/// is first inserted, followed by a `memref.cast`.
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static Value castToCompatibleMemRefType(OpBuilder &b, Value memref,
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MemRefType compatibleMemRefType) {
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MemRefType sourceType = memref.getType().cast<MemRefType>();
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Value res = memref;
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if (sourceType.getMemorySpace() != compatibleMemRefType.getMemorySpace()) {
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sourceType = MemRefType::get(
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sourceType.getShape(), sourceType.getElementType(),
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sourceType.getLayout(), compatibleMemRefType.getMemorySpace());
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res = b.create<memref::MemorySpaceCastOp>(memref.getLoc(), sourceType, res);
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}
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if (sourceType == compatibleMemRefType)
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return res;
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return b.create<memref::CastOp>(memref.getLoc(), compatibleMemRefType, res);
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}
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/// Operates under a scoped context to build the intersection between the
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/// view `xferOp.getSource()` @ `xferOp.getIndices()` and the view `alloc`.
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// TODO: view intersection/union/differences should be a proper std op.
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static std::pair<Value, Value>
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createSubViewIntersection(RewriterBase &b, VectorTransferOpInterface xferOp,
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Value alloc) {
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Location loc = xferOp.getLoc();
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int64_t memrefRank = xferOp.getShapedType().getRank();
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// TODO: relax this precondition, will require rank-reducing subviews.
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assert(memrefRank == cast<MemRefType>(alloc.getType()).getRank() &&
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"Expected memref rank to match the alloc rank");
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ValueRange leadingIndices =
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xferOp.getIndices().take_front(xferOp.getLeadingShapedRank());
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SmallVector<OpFoldResult, 4> sizes;
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sizes.append(leadingIndices.begin(), leadingIndices.end());
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auto isaWrite = isa<vector::TransferWriteOp>(xferOp);
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xferOp.zipResultAndIndexing([&](int64_t resultIdx, int64_t indicesIdx) {
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using MapList = ArrayRef<ArrayRef<AffineExpr>>;
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Value dimMemRef = b.create<memref::DimOp>(xferOp.getLoc(),
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xferOp.getSource(), indicesIdx);
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Value dimAlloc = b.create<memref::DimOp>(loc, alloc, resultIdx);
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Value index = xferOp.getIndices()[indicesIdx];
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AffineExpr i, j, k;
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bindDims(xferOp.getContext(), i, j, k);
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SmallVector<AffineMap, 4> maps =
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AffineMap::inferFromExprList(MapList{{i - j, k}}, b.getContext());
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// affine_min(%dimMemRef - %index, %dimAlloc)
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Value affineMin = b.create<affine::AffineMinOp>(
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loc, index.getType(), maps[0], ValueRange{dimMemRef, index, dimAlloc});
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sizes.push_back(affineMin);
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});
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SmallVector<OpFoldResult> srcIndices = llvm::to_vector<4>(llvm::map_range(
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xferOp.getIndices(), [](Value idx) -> OpFoldResult { return idx; }));
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SmallVector<OpFoldResult> destIndices(memrefRank, b.getIndexAttr(0));
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SmallVector<OpFoldResult> strides(memrefRank, b.getIndexAttr(1));
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auto copySrc = b.create<memref::SubViewOp>(
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loc, isaWrite ? alloc : xferOp.getSource(), srcIndices, sizes, strides);
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auto copyDest = b.create<memref::SubViewOp>(
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loc, isaWrite ? xferOp.getSource() : alloc, destIndices, sizes, strides);
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return std::make_pair(copySrc, copyDest);
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}
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/// Given an `xferOp` for which:
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/// 1. `inBoundsCond` and a `compatibleMemRefType` have been computed.
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/// 2. a memref of single vector `alloc` has been allocated.
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/// Produce IR resembling:
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/// ```
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/// %1:3 = scf.if (%inBounds) {
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/// (memref.memory_space_cast %A: memref<A..., addr_space> to memref<A...>)
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/// %view = memref.cast %A: memref<A...> to compatibleMemRefType
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/// scf.yield %view, ... : compatibleMemRefType, index, index
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/// } else {
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/// %2 = linalg.fill(%pad, %alloc)
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/// %3 = subview %view [...][...][...]
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/// %4 = subview %alloc [0, 0] [...] [...]
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/// linalg.copy(%3, %4)
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/// %5 = memref.cast %alloc: memref<B...> to compatibleMemRefType
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/// scf.yield %5, ... : compatibleMemRefType, index, index
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/// }
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/// ```
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/// Return the produced scf::IfOp.
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static scf::IfOp
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createFullPartialLinalgCopy(RewriterBase &b, vector::TransferReadOp xferOp,
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TypeRange returnTypes, Value inBoundsCond,
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MemRefType compatibleMemRefType, Value alloc) {
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Location loc = xferOp.getLoc();
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Value zero = b.create<arith::ConstantIndexOp>(loc, 0);
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Value memref = xferOp.getSource();
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return b.create<scf::IfOp>(
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loc, inBoundsCond,
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[&](OpBuilder &b, Location loc) {
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Value res = castToCompatibleMemRefType(b, memref, compatibleMemRefType);
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scf::ValueVector viewAndIndices{res};
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viewAndIndices.insert(viewAndIndices.end(), xferOp.getIndices().begin(),
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xferOp.getIndices().end());
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b.create<scf::YieldOp>(loc, viewAndIndices);
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},
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[&](OpBuilder &b, Location loc) {
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b.create<linalg::FillOp>(loc, ValueRange{xferOp.getPadding()},
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ValueRange{alloc});
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// Take partial subview of memref which guarantees no dimension
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// overflows.
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IRRewriter rewriter(b);
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std::pair<Value, Value> copyArgs = createSubViewIntersection(
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rewriter, cast<VectorTransferOpInterface>(xferOp.getOperation()),
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alloc);
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b.create<memref::CopyOp>(loc, copyArgs.first, copyArgs.second);
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Value casted =
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castToCompatibleMemRefType(b, alloc, compatibleMemRefType);
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scf::ValueVector viewAndIndices{casted};
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viewAndIndices.insert(viewAndIndices.end(), xferOp.getTransferRank(),
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zero);
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b.create<scf::YieldOp>(loc, viewAndIndices);
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});
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}
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/// Given an `xferOp` for which:
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/// 1. `inBoundsCond` and a `compatibleMemRefType` have been computed.
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/// 2. a memref of single vector `alloc` has been allocated.
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/// Produce IR resembling:
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/// ```
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/// %1:3 = scf.if (%inBounds) {
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/// (memref.memory_space_cast %A: memref<A..., addr_space> to memref<A...>)
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/// memref.cast %A: memref<A...> to compatibleMemRefType
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/// scf.yield %view, ... : compatibleMemRefType, index, index
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/// } else {
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/// %2 = vector.transfer_read %view[...], %pad : memref<A...>, vector<...>
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/// %3 = vector.type_cast %extra_alloc :
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/// memref<...> to memref<vector<...>>
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/// store %2, %3[] : memref<vector<...>>
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/// %4 = memref.cast %alloc: memref<B...> to compatibleMemRefType
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/// scf.yield %4, ... : compatibleMemRefType, index, index
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/// }
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/// ```
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/// Return the produced scf::IfOp.
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static scf::IfOp createFullPartialVectorTransferRead(
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RewriterBase &b, vector::TransferReadOp xferOp, TypeRange returnTypes,
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Value inBoundsCond, MemRefType compatibleMemRefType, Value alloc) {
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Location loc = xferOp.getLoc();
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scf::IfOp fullPartialIfOp;
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Value zero = b.create<arith::ConstantIndexOp>(loc, 0);
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Value memref = xferOp.getSource();
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return b.create<scf::IfOp>(
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loc, inBoundsCond,
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[&](OpBuilder &b, Location loc) {
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Value res = castToCompatibleMemRefType(b, memref, compatibleMemRefType);
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scf::ValueVector viewAndIndices{res};
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viewAndIndices.insert(viewAndIndices.end(), xferOp.getIndices().begin(),
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xferOp.getIndices().end());
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b.create<scf::YieldOp>(loc, viewAndIndices);
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},
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[&](OpBuilder &b, Location loc) {
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Operation *newXfer = b.clone(*xferOp.getOperation());
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Value vector = cast<VectorTransferOpInterface>(newXfer).getVector();
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b.create<memref::StoreOp>(
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loc, vector,
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b.create<vector::TypeCastOp>(
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loc, MemRefType::get({}, vector.getType()), alloc));
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Value casted =
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castToCompatibleMemRefType(b, alloc, compatibleMemRefType);
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scf::ValueVector viewAndIndices{casted};
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viewAndIndices.insert(viewAndIndices.end(), xferOp.getTransferRank(),
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zero);
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b.create<scf::YieldOp>(loc, viewAndIndices);
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});
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}
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/// Given an `xferOp` for which:
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/// 1. `inBoundsCond` and a `compatibleMemRefType` have been computed.
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/// 2. a memref of single vector `alloc` has been allocated.
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/// Produce IR resembling:
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/// ```
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/// %1:3 = scf.if (%inBounds) {
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/// memref.cast %A: memref<A...> to compatibleMemRefType
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/// scf.yield %view, ... : compatibleMemRefType, index, index
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/// } else {
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/// %3 = vector.type_cast %extra_alloc :
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/// memref<...> to memref<vector<...>>
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/// %4 = memref.cast %alloc: memref<B...> to compatibleMemRefType
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/// scf.yield %4, ... : compatibleMemRefType, index, index
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/// }
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/// ```
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static ValueRange
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getLocationToWriteFullVec(RewriterBase &b, vector::TransferWriteOp xferOp,
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TypeRange returnTypes, Value inBoundsCond,
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MemRefType compatibleMemRefType, Value alloc) {
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Location loc = xferOp.getLoc();
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Value zero = b.create<arith::ConstantIndexOp>(loc, 0);
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Value memref = xferOp.getSource();
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return b
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.create<scf::IfOp>(
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loc, inBoundsCond,
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[&](OpBuilder &b, Location loc) {
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Value res =
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castToCompatibleMemRefType(b, memref, compatibleMemRefType);
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scf::ValueVector viewAndIndices{res};
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viewAndIndices.insert(viewAndIndices.end(),
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xferOp.getIndices().begin(),
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xferOp.getIndices().end());
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b.create<scf::YieldOp>(loc, viewAndIndices);
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},
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[&](OpBuilder &b, Location loc) {
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Value casted =
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castToCompatibleMemRefType(b, alloc, compatibleMemRefType);
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scf::ValueVector viewAndIndices{casted};
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viewAndIndices.insert(viewAndIndices.end(),
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xferOp.getTransferRank(), zero);
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b.create<scf::YieldOp>(loc, viewAndIndices);
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})
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->getResults();
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}
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/// Given an `xferOp` for which:
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/// 1. `inBoundsCond` has been computed.
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/// 2. a memref of single vector `alloc` has been allocated.
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/// 3. it originally wrote to %view
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/// Produce IR resembling:
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/// ```
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/// %notInBounds = arith.xori %inBounds, %true
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/// scf.if (%notInBounds) {
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/// %3 = subview %alloc [...][...][...]
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/// %4 = subview %view [0, 0][...][...]
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/// linalg.copy(%3, %4)
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/// }
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/// ```
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static void createFullPartialLinalgCopy(RewriterBase &b,
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vector::TransferWriteOp xferOp,
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Value inBoundsCond, Value alloc) {
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Location loc = xferOp.getLoc();
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auto notInBounds = b.create<arith::XOrIOp>(
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loc, inBoundsCond, b.create<arith::ConstantIntOp>(loc, true, 1));
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b.create<scf::IfOp>(loc, notInBounds, [&](OpBuilder &b, Location loc) {
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IRRewriter rewriter(b);
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std::pair<Value, Value> copyArgs = createSubViewIntersection(
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rewriter, cast<VectorTransferOpInterface>(xferOp.getOperation()),
|
|
alloc);
|
|
b.create<memref::CopyOp>(loc, copyArgs.first, copyArgs.second);
|
|
b.create<scf::YieldOp>(loc, ValueRange{});
|
|
});
|
|
}
|
|
|
|
/// Given an `xferOp` for which:
|
|
/// 1. `inBoundsCond` has been computed.
|
|
/// 2. a memref of single vector `alloc` has been allocated.
|
|
/// 3. it originally wrote to %view
|
|
/// Produce IR resembling:
|
|
/// ```
|
|
/// %notInBounds = arith.xori %inBounds, %true
|
|
/// scf.if (%notInBounds) {
|
|
/// %2 = load %alloc : memref<vector<...>>
|
|
/// vector.transfer_write %2, %view[...] : memref<A...>, vector<...>
|
|
/// }
|
|
/// ```
|
|
static void createFullPartialVectorTransferWrite(RewriterBase &b,
|
|
vector::TransferWriteOp xferOp,
|
|
Value inBoundsCond,
|
|
Value alloc) {
|
|
Location loc = xferOp.getLoc();
|
|
auto notInBounds = b.create<arith::XOrIOp>(
|
|
loc, inBoundsCond, b.create<arith::ConstantIntOp>(loc, true, 1));
|
|
b.create<scf::IfOp>(loc, notInBounds, [&](OpBuilder &b, Location loc) {
|
|
IRMapping mapping;
|
|
Value load = b.create<memref::LoadOp>(
|
|
loc,
|
|
b.create<vector::TypeCastOp>(
|
|
loc, MemRefType::get({}, xferOp.getVector().getType()), alloc),
|
|
ValueRange());
|
|
mapping.map(xferOp.getVector(), load);
|
|
b.clone(*xferOp.getOperation(), mapping);
|
|
b.create<scf::YieldOp>(loc, ValueRange{});
|
|
});
|
|
}
|
|
|
|
// TODO: Parallelism and threadlocal considerations with a ParallelScope trait.
|
|
static Operation *getAutomaticAllocationScope(Operation *op) {
|
|
// Find the closest surrounding allocation scope that is not a known looping
|
|
// construct (putting alloca's in loops doesn't always lower to deallocation
|
|
// until the end of the loop).
|
|
Operation *scope = nullptr;
|
|
for (Operation *parent = op->getParentOp(); parent != nullptr;
|
|
parent = parent->getParentOp()) {
|
|
if (parent->hasTrait<OpTrait::AutomaticAllocationScope>())
|
|
scope = parent;
|
|
if (!isa<scf::ForOp, affine::AffineForOp>(parent))
|
|
break;
|
|
}
|
|
assert(scope && "Expected op to be inside automatic allocation scope");
|
|
return scope;
|
|
}
|
|
|
|
/// Split a vector.transfer operation into an in-bounds (i.e., no out-of-bounds
|
|
/// masking) fastpath and a slowpath.
|
|
///
|
|
/// For vector.transfer_read:
|
|
/// If `ifOp` is not null and the result is `success, the `ifOp` points to the
|
|
/// newly created conditional upon function return.
|
|
/// To accomodate for the fact that the original vector.transfer indexing may be
|
|
/// arbitrary and the slow path indexes @[0...0] in the temporary buffer, the
|
|
/// scf.if op returns a view and values of type index.
|
|
///
|
|
/// Example (a 2-D vector.transfer_read):
|
|
/// ```
|
|
/// %1 = vector.transfer_read %0[...], %pad : memref<A...>, vector<...>
|
|
/// ```
|
|
/// is transformed into:
|
|
/// ```
|
|
/// %1:3 = scf.if (%inBounds) {
|
|
/// // fastpath, direct cast
|
|
/// memref.cast %A: memref<A...> to compatibleMemRefType
|
|
/// scf.yield %view : compatibleMemRefType, index, index
|
|
/// } else {
|
|
/// // slowpath, not in-bounds vector.transfer or linalg.copy.
|
|
/// memref.cast %alloc: memref<B...> to compatibleMemRefType
|
|
/// scf.yield %4 : compatibleMemRefType, index, index
|
|
// }
|
|
/// %0 = vector.transfer_read %1#0[%1#1, %1#2] {in_bounds = [true ... true]}
|
|
/// ```
|
|
/// where `alloc` is a top of the function alloca'ed buffer of one vector.
|
|
///
|
|
/// For vector.transfer_write:
|
|
/// There are 2 conditional blocks. First a block to decide which memref and
|
|
/// indices to use for an unmasked, inbounds write. Then a conditional block to
|
|
/// further copy a partial buffer into the final result in the slow path case.
|
|
///
|
|
/// Example (a 2-D vector.transfer_write):
|
|
/// ```
|
|
/// vector.transfer_write %arg, %0[...], %pad : memref<A...>, vector<...>
|
|
/// ```
|
|
/// is transformed into:
|
|
/// ```
|
|
/// %1:3 = scf.if (%inBounds) {
|
|
/// memref.cast %A: memref<A...> to compatibleMemRefType
|
|
/// scf.yield %view : compatibleMemRefType, index, index
|
|
/// } else {
|
|
/// memref.cast %alloc: memref<B...> to compatibleMemRefType
|
|
/// scf.yield %4 : compatibleMemRefType, index, index
|
|
/// }
|
|
/// %0 = vector.transfer_write %arg, %1#0[%1#1, %1#2] {in_bounds = [true ...
|
|
/// true]}
|
|
/// scf.if (%notInBounds) {
|
|
/// // slowpath: not in-bounds vector.transfer or linalg.copy.
|
|
/// }
|
|
/// ```
|
|
/// where `alloc` is a top of the function alloca'ed buffer of one vector.
|
|
///
|
|
/// Preconditions:
|
|
/// 1. `xferOp.getPermutationMap()` must be a minor identity map
|
|
/// 2. the rank of the `xferOp.getSource()` and the rank of the
|
|
/// `xferOp.getVector()` must be equal. This will be relaxed in the future
|
|
/// but requires rank-reducing subviews.
|
|
LogicalResult mlir::vector::splitFullAndPartialTransfer(
|
|
RewriterBase &b, VectorTransferOpInterface xferOp,
|
|
VectorTransformsOptions options, scf::IfOp *ifOp) {
|
|
if (options.vectorTransferSplit == VectorTransferSplit::None)
|
|
return failure();
|
|
|
|
SmallVector<bool, 4> bools(xferOp.getTransferRank(), true);
|
|
auto inBoundsAttr = b.getBoolArrayAttr(bools);
|
|
if (options.vectorTransferSplit == VectorTransferSplit::ForceInBounds) {
|
|
b.modifyOpInPlace(xferOp, [&]() {
|
|
xferOp->setAttr(xferOp.getInBoundsAttrName(), inBoundsAttr);
|
|
});
|
|
return success();
|
|
}
|
|
|
|
// Assert preconditions. Additionally, keep the variables in an inner scope to
|
|
// ensure they aren't used in the wrong scopes further down.
|
|
{
|
|
assert(succeeded(splitFullAndPartialTransferPrecondition(xferOp)) &&
|
|
"Expected splitFullAndPartialTransferPrecondition to hold");
|
|
|
|
auto xferReadOp = dyn_cast<vector::TransferReadOp>(xferOp.getOperation());
|
|
auto xferWriteOp = dyn_cast<vector::TransferWriteOp>(xferOp.getOperation());
|
|
|
|
if (!(xferReadOp || xferWriteOp))
|
|
return failure();
|
|
if (xferWriteOp && xferWriteOp.getMask())
|
|
return failure();
|
|
if (xferReadOp && xferReadOp.getMask())
|
|
return failure();
|
|
}
|
|
|
|
RewriterBase::InsertionGuard guard(b);
|
|
b.setInsertionPoint(xferOp);
|
|
Value inBoundsCond = createInBoundsCond(
|
|
b, cast<VectorTransferOpInterface>(xferOp.getOperation()));
|
|
if (!inBoundsCond)
|
|
return failure();
|
|
|
|
// Top of the function `alloc` for transient storage.
|
|
Value alloc;
|
|
{
|
|
RewriterBase::InsertionGuard guard(b);
|
|
Operation *scope = getAutomaticAllocationScope(xferOp);
|
|
assert(scope->getNumRegions() == 1 &&
|
|
"AutomaticAllocationScope with >1 regions");
|
|
b.setInsertionPointToStart(&scope->getRegion(0).front());
|
|
auto shape = xferOp.getVectorType().getShape();
|
|
Type elementType = xferOp.getVectorType().getElementType();
|
|
alloc = b.create<memref::AllocaOp>(scope->getLoc(),
|
|
MemRefType::get(shape, elementType),
|
|
ValueRange{}, b.getI64IntegerAttr(32));
|
|
}
|
|
|
|
MemRefType compatibleMemRefType =
|
|
getCastCompatibleMemRefType(cast<MemRefType>(xferOp.getShapedType()),
|
|
cast<MemRefType>(alloc.getType()));
|
|
if (!compatibleMemRefType)
|
|
return failure();
|
|
|
|
SmallVector<Type, 4> returnTypes(1 + xferOp.getTransferRank(),
|
|
b.getIndexType());
|
|
returnTypes[0] = compatibleMemRefType;
|
|
|
|
if (auto xferReadOp =
|
|
dyn_cast<vector::TransferReadOp>(xferOp.getOperation())) {
|
|
// Read case: full fill + partial copy -> in-bounds vector.xfer_read.
|
|
scf::IfOp fullPartialIfOp =
|
|
options.vectorTransferSplit == VectorTransferSplit::VectorTransfer
|
|
? createFullPartialVectorTransferRead(b, xferReadOp, returnTypes,
|
|
inBoundsCond,
|
|
compatibleMemRefType, alloc)
|
|
: createFullPartialLinalgCopy(b, xferReadOp, returnTypes,
|
|
inBoundsCond, compatibleMemRefType,
|
|
alloc);
|
|
if (ifOp)
|
|
*ifOp = fullPartialIfOp;
|
|
|
|
// Set existing read op to in-bounds, it always reads from a full buffer.
|
|
for (unsigned i = 0, e = returnTypes.size(); i != e; ++i)
|
|
xferReadOp.setOperand(i, fullPartialIfOp.getResult(i));
|
|
|
|
b.modifyOpInPlace(xferOp, [&]() {
|
|
xferOp->setAttr(xferOp.getInBoundsAttrName(), inBoundsAttr);
|
|
});
|
|
|
|
return success();
|
|
}
|
|
|
|
auto xferWriteOp = cast<vector::TransferWriteOp>(xferOp.getOperation());
|
|
|
|
// Decide which location to write the entire vector to.
|
|
auto memrefAndIndices = getLocationToWriteFullVec(
|
|
b, xferWriteOp, returnTypes, inBoundsCond, compatibleMemRefType, alloc);
|
|
|
|
// Do an in bounds write to either the output or the extra allocated buffer.
|
|
// The operation is cloned to prevent deleting information needed for the
|
|
// later IR creation.
|
|
IRMapping mapping;
|
|
mapping.map(xferWriteOp.getSource(), memrefAndIndices.front());
|
|
mapping.map(xferWriteOp.getIndices(), memrefAndIndices.drop_front());
|
|
auto *clone = b.clone(*xferWriteOp, mapping);
|
|
clone->setAttr(xferWriteOp.getInBoundsAttrName(), inBoundsAttr);
|
|
|
|
// Create a potential copy from the allocated buffer to the final output in
|
|
// the slow path case.
|
|
if (options.vectorTransferSplit == VectorTransferSplit::VectorTransfer)
|
|
createFullPartialVectorTransferWrite(b, xferWriteOp, inBoundsCond, alloc);
|
|
else
|
|
createFullPartialLinalgCopy(b, xferWriteOp, inBoundsCond, alloc);
|
|
|
|
b.eraseOp(xferOp);
|
|
|
|
return success();
|
|
}
|
|
|
|
namespace {
|
|
/// Apply `splitFullAndPartialTransfer` selectively via a pattern. This pattern
|
|
/// may take an extra filter to perform selection at a finer granularity.
|
|
struct VectorTransferFullPartialRewriter : public RewritePattern {
|
|
using FilterConstraintType =
|
|
std::function<LogicalResult(VectorTransferOpInterface op)>;
|
|
|
|
explicit VectorTransferFullPartialRewriter(
|
|
MLIRContext *context,
|
|
VectorTransformsOptions options = VectorTransformsOptions(),
|
|
FilterConstraintType filter =
|
|
[](VectorTransferOpInterface op) { return success(); },
|
|
PatternBenefit benefit = 1)
|
|
: RewritePattern(MatchAnyOpTypeTag(), benefit, context), options(options),
|
|
filter(std::move(filter)) {}
|
|
|
|
/// Performs the rewrite.
|
|
LogicalResult matchAndRewrite(Operation *op,
|
|
PatternRewriter &rewriter) const override;
|
|
|
|
private:
|
|
VectorTransformsOptions options;
|
|
FilterConstraintType filter;
|
|
};
|
|
|
|
} // namespace
|
|
|
|
LogicalResult VectorTransferFullPartialRewriter::matchAndRewrite(
|
|
Operation *op, PatternRewriter &rewriter) const {
|
|
auto xferOp = dyn_cast<VectorTransferOpInterface>(op);
|
|
if (!xferOp || failed(splitFullAndPartialTransferPrecondition(xferOp)) ||
|
|
failed(filter(xferOp)))
|
|
return failure();
|
|
return splitFullAndPartialTransfer(rewriter, xferOp, options);
|
|
}
|
|
|
|
void mlir::vector::populateVectorTransferFullPartialPatterns(
|
|
RewritePatternSet &patterns, const VectorTransformsOptions &options) {
|
|
patterns.add<VectorTransferFullPartialRewriter>(patterns.getContext(),
|
|
options);
|
|
}
|