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//===- Loops.cpp - conversion from Linalg named and generic ops to loops --===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "PassDetail.h"
#include "mlir/Dialect/Affine/EDSC/Intrinsics.h"
#include "mlir/Dialect/Linalg/EDSC/FoldedIntrinsics.h"
#include "mlir/Dialect/Linalg/IR/LinalgOps.h"
#include "mlir/Dialect/Linalg/IR/LinalgTypes.h"
#include "mlir/Dialect/Linalg/Passes.h"
#include "mlir/Dialect/Linalg/Transforms/Transforms.h"
#include "mlir/Dialect/Linalg/Utils/Utils.h"
#include "mlir/Dialect/SCF/EDSC/Builders.h"
#include "mlir/Dialect/StandardOps/EDSC/Intrinsics.h"
#include "mlir/IR/AffineExpr.h"
#include "mlir/IR/AffineMap.h"
#include "mlir/IR/BlockAndValueMapping.h"
#include "mlir/Support/LLVM.h"
#include "mlir/Transforms/DialectConversion.h"
#include "mlir/Transforms/FoldUtils.h"
#include "mlir/Transforms/GreedyPatternRewriteDriver.h"
#include "llvm/ADT/TypeSwitch.h"
using namespace mlir;
using namespace mlir::edsc;
using namespace mlir::edsc::intrinsics;
using namespace mlir::linalg;
using edsc::op::operator+;
static SmallVector<Value, 8> makeCanonicalAffineApplies(OpBuilder &b,
Location loc,
AffineMap map,
ArrayRef<Value> vals) {
if (map.isEmpty())
return {};
assert(map.getNumInputs() == vals.size());
SmallVector<Value, 8> res;
res.reserve(map.getNumResults());
auto dims = map.getNumDims();
for (auto e : map.getResults()) {
auto exprMap = AffineMap::get(dims, map.getNumSymbols(), e);
SmallVector<Value, 4> operands(vals.begin(), vals.end());
canonicalizeMapAndOperands(&exprMap, &operands);
res.push_back(affine_apply(exprMap, operands));
}
return res;
}
static SmallVector<Value, 4> permuteIvs(ArrayRef<Value> ivs,
Optional<AffineMap> permutation) {
return permutation ? applyMapToValues(ScopedContext::getBuilderRef(),
ScopedContext::getLocation(),
permutation.getValue(), ivs)
: SmallVector<Value, 4>(ivs.begin(), ivs.end());
}
template <typename IndexedValueType, typename OpType>
static void inlineRegionAndEmitStore(OpType op, ArrayRef<Value> indexedValues,
ArrayRef<SmallVector<Value, 8>> indexing,
ArrayRef<Value> outputBuffers) {
assert(op->getNumRegions() == 1 && "Expected single region op");
auto &b = ScopedContext::getBuilderRef();
auto &block = op->getRegion(0).front();
BlockAndValueMapping map;
map.map(block.getArguments(), indexedValues);
for (auto &op : block.without_terminator()) {
assert(op.getNumRegions() == 0 && "expected a non-nested region");
auto *newOp = b.clone(op, map);
map.map(op.getResults(), newOp->getResults());
}
Operation &terminator = block.back();
assert(isa<linalg::YieldOp>(terminator) &&
"expected a yield op in the end of the region");
for (unsigned i = 0, e = terminator.getNumOperands(); i < e; ++i) {
IndexedValueType O(outputBuffers[i]);
O(indexing[i]) = map.lookupOrDefault(terminator.getOperand(i));
}
}
// Returns a pair that contains input indices and output indices of a
// SingleInputPoolingOp `op`.
struct InputAndOutputIndices {
SmallVector<Value, 8> inputs;
SmallVector<Value, 8> outputs;
};
template <typename SingleInputPoolingOp>
static InputAndOutputIndices getInputAndOutputIndices(ArrayRef<Value> allIvs,
SingleInputPoolingOp op) {
auto &b = ScopedContext::getBuilderRef();
auto loc = ScopedContext::getLocation();
auto mapsRange = op.indexing_maps().template getAsRange<AffineMapAttr>();
auto maps = llvm::to_vector<8>(
llvm::map_range(mapsRange, [](AffineMapAttr a) { return a.getValue(); }));
return InputAndOutputIndices{
makeCanonicalAffineApplies(b, loc, maps[0], allIvs),
makeCanonicalAffineApplies(b, loc, maps[2], allIvs)};
}
/// Emits the MLIR for the scalar part of the generic op by:
/// 1. Emitting load ops for each input and output view in order. This is
/// achieved by applying the appropriate input or output map to the
/// enclosing induction variables.
/// 2. Emitting a call to `op.fun()` that takes as arguments the scalars
/// from point 1. above.
/// 3. Emitting store ops to store the results of 2. to the output
/// views.
///
/// An example output may resemble:
///
/// ```
/// scf.for %i = %c0 to %0 step %c1 {
/// scf.for %j = %c0 to %1 step %c1 {
/// scf.for %k = %c0 to %4 step %c1 {
/// %11 = load %arg0[%i, %j] :
/// memref<?x?xf32, stride_specification>
/// %12 = load %arg1[%i, %j, %k] :
/// memref<?x?x?xf32, stride_specification>
/// %13 = load %arg2[%i, %k, %j] :
/// memref<?x?x?xf32, stride_specification>
/// %14:2 = call @foo(%11, %12, %13) : (f32, f32, f32) -> (f32, f32)
/// store %14#0, %arg1[%i, %j, %k] :
/// memref<?x?x?Xf32, stride_specification>
/// store %14#1, %arg2[%i, %k, %j] :
/// memref<?x?x?Xf32, stride_specification>
/// }
/// }
/// }
/// ```
template <typename IndexedValueType>
static void emitScalarImplementation(ArrayRef<Value> allIvs,
LinalgOp linalgOp) {
assert(linalgOp.hasBufferSemantics() &&
"expected linalg op with buffer semantics");
auto &b = ScopedContext::getBuilderRef();
auto loc = ScopedContext::getLocation();
unsigned nInputs = linalgOp.getNumInputs();
unsigned nOutputs = linalgOp.getNumOutputs();
SmallVector<Value, 4> indexedValues;
indexedValues.reserve(nInputs + nOutputs);
auto allIvsPlusDims = SmallVector<Value, 4>(allIvs.begin(), allIvs.end());
// TODO: Avoid the loads if the corresponding argument of the
// region has no uses.
// 1.a. Emit load from input views.
for (unsigned i = 0; i < nInputs; ++i) {
auto indexing = makeCanonicalAffineApplies(
b, loc, linalgOp.getInputIndexingMap(i), allIvsPlusDims);
// Passing through IndexedValueType emits the proper load operation.
indexedValues.push_back(IndexedValueType(linalgOp.getInput(i))(indexing));
}
// 1.b. Emit load from output views.
for (unsigned i = 0; i < nOutputs; ++i) {
auto indexing = makeCanonicalAffineApplies(
b, loc, linalgOp.getOutputIndexingMap(i), allIvsPlusDims);
// Passing through IndexedValueType emits the proper load operation.
indexedValues.push_back(
IndexedValueType(linalgOp.getOutputBuffer(i))(indexing));
}
// TODO: When a region inliner exists, use it.
// 2. Inline region, currently only works for a single basic block.
// 3. Emit store.
SmallVector<SmallVector<Value, 8>, 8> indexing;
SmallVector<Value, 8> outputBuffers;
for (unsigned i = 0; i < nOutputs; ++i) {
indexing.push_back(makeCanonicalAffineApplies(
b, loc, linalgOp.getOutputIndexingMap(i), allIvsPlusDims));
outputBuffers.push_back(linalgOp.getOutputBuffer(i));
}
inlineRegionAndEmitStore<IndexedValueType>(linalgOp, indexedValues, indexing,
outputBuffers);
}
template <typename IndexedValueType>
static void emitScalarImplementation(ArrayRef<Value> allIvs, CopyOp copyOp) {
assert(copyOp.hasBufferSemantics() &&
"expected linalg op with buffer semantics");
auto nPar = copyOp.getNumParallelLoops();
assert(nPar == allIvs.size());
auto inputIvs =
permuteIvs(allIvs.take_front(nPar), copyOp.inputPermutation());
auto outputIvs =
permuteIvs(allIvs.take_front(nPar), copyOp.outputPermutation());
SmallVector<Value, 8> iivs(inputIvs.begin(), inputIvs.end());
SmallVector<Value, 8> oivs(outputIvs.begin(), outputIvs.end());
IndexedValueType O(copyOp.getOutputBuffer(0)), I(copyOp.getInput(0));
// Emit the proper scalar assignment, whether we are dealing with a 0-D or
// an n-D loop nest; with or without permutations.
// clang-format off
nPar > 0 ? O(oivs) = I(iivs) :
O() = I();
// clang-format on
}
template <typename IndexedValueType>
static void emitScalarImplementation(ArrayRef<Value> allIvs, FillOp fillOp) {
assert(fillOp.hasBufferSemantics() &&
"expected linalg op with buffer semantics");
auto nPar = fillOp.getNumParallelLoops();
assert(nPar == allIvs.size());
auto ivs = SmallVector<Value, 4>(allIvs.begin(), allIvs.begin() + nPar);
IndexedValueType O(fillOp.getOutputBuffer(0));
// Emit the proper scalar assignment, whether we are dealing with a 0-D or
// an n-D loop nest; with or without permutations.
nPar > 0 ? O(ivs) = fillOp.value() : O() = fillOp.value();
}
// Create a padded view into the given `input` tensor using the 'indices'
// to access the tensor. `skipPadding` lists the dimensions for which no padding
// is needed e.g. the non-spatial dimensions for convolutions.
template <typename IndexedValueType>
Value getPaddedInput(Value input, ArrayRef<Value> indices,
ArrayRef<int> skipPadding, Value padValue) {
// TODO: add a level of indirection to linalg.generic.
IndexedValueType indexedInput(input);
auto *context = ScopedContext::getContext();
Value zeroIndex = std_constant_index(0);
SmallVector<Value, 8> conds;
SmallVector<Value, 8> clampedImIdx;
for (auto iter : llvm::enumerate(indices)) {
int idx = iter.index();
auto dim = iter.value();
if (is_contained(skipPadding, idx)) {
clampedImIdx.push_back(dim);
continue;
}
using edsc::op::sge;
using edsc::op::slt;
using edsc::op::operator||;
Value leftOutOfBound = slt(dim, zeroIndex);
if (conds.empty())
conds.push_back(leftOutOfBound);
else
conds.push_back(conds.back() || leftOutOfBound);
Value rightBound = std_dim(input, idx);
conds.push_back(conds.back() || (sge(dim, rightBound)));
// When padding is involved, the indices will only be shifted to negative,
// so having a max op is enough.
auto maxMap = AffineMap::get(/*dimCount=*/1, 0,
{getAffineDimExpr(/*position=*/0, context),
getAffineConstantExpr(0, context)},
context);
clampedImIdx.push_back(affine_max(dim.getType(), maxMap, ValueRange{dim}));
}
Value readInput = indexedInput(clampedImIdx);
return conds.empty() ? readInput
: (Value)std_select(conds.back(), padValue, readInput);
}
namespace {
/// The padding value for a given Op depends on the semantics of the Op.
/// The identity value for ConvOp and PoolingSumOp is 0, for PoolingMaxOp is
/// -inf or minInt and for PoolingMinOp is inf or maxInt.
template <typename OpType>
Attribute getPadValueAttr(Type type) {
llvm_unreachable("Unexpected op type for getPadValueAttr");
return {};
}
template <>
Attribute getPadValueAttr<PoolingMaxOp>(Type type) {
auto &b = ScopedContext::getBuilderRef();
if (auto floatType = type.dyn_cast<FloatType>()) {
return b.getFloatAttr(
floatType,
APFloat::getInf(floatType.getFloatSemantics(), /*Negative*/ true));
}
if (auto intType = type.dyn_cast<IntegerType>()) {
unsigned width = intType.getWidth();
// The select instruction used to lower the PoolingMin uses a signed
// comparison, use a signed constant irrespective of the signedness of the
// integer type.
return b.getIntegerAttr(intType, APInt::getSignedMinValue(width));
}
llvm_unreachable("Unsupported data type for PoolingMaxOp");
return {};
}
template <>
Attribute getPadValueAttr<PoolingMinOp>(Type type) {
auto &b = ScopedContext::getBuilderRef();
if (auto floatType = type.dyn_cast<FloatType>()) {
return b.getFloatAttr(floatType,
APFloat::getInf(floatType.getFloatSemantics()));
}
if (auto intType = type.dyn_cast<IntegerType>()) {
unsigned width = intType.getWidth();
// The select instruction used to lower the PoolingMin uses a signed
// comparison, use a signed constant irrespective of the signedness of the
// integer type.
return b.getIntegerAttr(intType, APInt::getSignedMaxValue(width));
}
llvm_unreachable("Unsupported data type for PoolingMinOp");
return {};
}
template <>
Attribute getPadValueAttr<PoolingSumOp>(Type type) {
auto &b = ScopedContext::getBuilderRef();
return b.getZeroAttr(type);
}
template <>
Attribute getPadValueAttr<ConvOp>(Type type) {
auto &b = ScopedContext::getBuilderRef();
return b.getZeroAttr(type);
}
} // namespace
/// Returns true is `convOp` has a non-zero padding.
static bool hasPadding(ConvOp convOp) {
for (unsigned i = 0, e = convOp.getNumSpatialDimensions(); i < e; ++i) {
if (convOp.getLowPad(i) > 0 || convOp.getHighPad(i) > 0)
return true;
}
return false;
}
template <typename IndexedValueType>
static void emitScalarImplementation(ArrayRef<Value> allIvs, ConvOp convOp) {
assert(convOp.hasBufferSemantics() &&
"expected linalg op with buffer semantics");
auto &b = ScopedContext::getBuilderRef();
auto loc = ScopedContext::getLocation();
auto mapsRange = convOp.indexing_maps().getAsRange<AffineMapAttr>();
auto maps = llvm::to_vector<8>(
llvm::map_range(mapsRange, [](AffineMapAttr a) { return a.getValue(); }));
SmallVector<Value, 8> fIdx(
makeCanonicalAffineApplies(b, loc, maps[0], allIvs));
SmallVector<Value, 8> imIdx(
makeCanonicalAffineApplies(b, loc, maps[1], allIvs));
SmallVector<Value, 8> oIdx(
makeCanonicalAffineApplies(b, loc, maps[2], allIvs));
IndexedValueType F(convOp.filter()), O(convOp.output());
// Emit scalar form. Padded conv involves an affine.max in the memory access
// which is not allowed by affine.load. Override to use an StdIndexedValue
// when there is non-zero padding.
if (hasPadding(convOp)) {
Type type = convOp.input().getType().cast<MemRefType>().getElementType();
Value padValue = std_constant(type, getPadValueAttr<ConvOp>(type));
Value paddedInput = getPaddedInput<StdIndexedValue>(
convOp.input(), imIdx,
/* Only need to pad the window dimensions */
{0, static_cast<int>(imIdx.size()) - 1}, padValue);
O(oIdx) += F(fIdx) * paddedInput;
} else {
IndexedValueType I(convOp.input());
O(oIdx) += F(fIdx) * I(imIdx);
}
}
template <typename PoolingOp>
static bool hasPadding(PoolingOp poolingOp) {
for (unsigned i = 0, e = poolingOp.getNumWindowLoops(); i < e; ++i) {
if (poolingOp.getLowPad(i) > 0 || poolingOp.getHighPad(i) > 0)
return true;
}
return false;
}
template <typename IndexedValueType, typename PoolingOp>
static Value getPoolingInput(PoolingOp op, ArrayRef<Value> inputIndices) {
if (hasPadding(op)) {
Type type =
op.input().getType().template cast<MemRefType>().getElementType();
Value padValue = std_constant(type, getPadValueAttr<PoolingOp>(type));
return getPaddedInput<StdIndexedValue>(op.input(), inputIndices,
/*Pad every dimension*/ {},
padValue);
}
IndexedValueType input(op.input());
return input(inputIndices);
}
template <typename IndexedValueType, typename OpType>
void emitPoolingMinMaxScalarImplementation(ArrayRef<Value> allIvs, OpType op) {
InputAndOutputIndices indices = getInputAndOutputIndices(allIvs, op);
// Emit scalar form.
IndexedValueType output(op.output());
Value lhs = output(indices.outputs);
Value rhs = getPoolingInput<IndexedValueType>(op, indices.inputs);
using edsc::op::sgt;
using edsc::op::slt;
Value value = std::is_same<OpType, PoolingMinOp>()
? std_select(slt(lhs, rhs), lhs, rhs)
: std_select(sgt(lhs, rhs), lhs, rhs);
output(indices.outputs) = value;
}
template <typename IndexedValueType>
static void emitScalarImplementation(ArrayRef<Value> allIvs, PoolingMaxOp op) {
emitPoolingMinMaxScalarImplementation<IndexedValueType, PoolingMaxOp>(allIvs,
op);
}
template <typename IndexedValueType>
static void emitScalarImplementation(ArrayRef<Value> allIvs, PoolingMinOp op) {
emitPoolingMinMaxScalarImplementation<IndexedValueType, PoolingMinOp>(allIvs,
op);
}
template <typename IndexedValueType>
static void emitScalarImplementation(ArrayRef<Value> allIvs, PoolingSumOp op) {
auto indices = getInputAndOutputIndices(allIvs, op);
IndexedValueType output(op.output());
// Emit scalar form.
output(indices.outputs) +=
getPoolingInput<IndexedValueType>(op, indices.inputs);
}
/// Emits the MLIR for the scalar part of the indexed generic op by:
/// 1. Emitting load ops for each input and output view in order. This is
/// achieved by applying the appropriate input or output map to the
/// enclosing induction variables.
/// 2. Emitting a call to `op.fun()` that takes as arguments the induction
/// variables and the scalars from point 1. above.
/// 3. Emitting store ops to store the results of 2. to the output views.
///
/// An example output may resemble:
///
/// ```
/// scf.for %i = %c0 to %0 step %c1 {
/// scf.for %j = %c0 to %1 step %c1 {
/// scf.for %k = %c0 to %4 step %c1 {
/// %11 = load %arg0[%i, %j] :
/// memref<?x?xf32, stride_specification>
/// %12 = load %arg1[%i, %j, %k] :
/// memref<?x?x?xf32, stride_specification>
/// %13 = load %arg2[%i, %k, %j] :
/// memref<?x?x?xf32, stride_specification>
/// %14:2 = call @foo(%i, %j, %k, %11, %12, %13) :
/// (index, index, index, f32, f32, f32) -> (f32, f32)
/// store %14#0, %arg1[%i, %j, %k] :
/// memref<?x?x?Xf32, stride_specification>
/// store %14#1, %arg2[%i, %k, %j] :
/// memref<?x?x?Xf32, stride_specification>
/// }
/// }
/// }
/// ```
template <typename IndexedValueType>
static void emitScalarImplementation(ArrayRef<Value> allIvs,
IndexedGenericOp indexedGenericOp) {
assert(indexedGenericOp.hasBufferSemantics() &&
"expected linalg op with buffer semantics");
auto &b = ScopedContext::getBuilderRef();
auto loc = ScopedContext::getLocation();
unsigned nInputs = indexedGenericOp.getNumInputs();
unsigned nOutputs = indexedGenericOp.getNumOutputs();
unsigned nLoops = allIvs.size();
SmallVector<Value, 4> indexedValues;
indexedValues.reserve(nLoops + nInputs + nOutputs);
for (unsigned i = 0; i < nLoops; ++i)
indexedValues.push_back(allIvs[i]);
// TODO: Avoid the loads if the corresponding argument of the
// region has no uses.
// 1.a. Emit load from input views.
for (unsigned i = 0; i < nInputs; ++i) {
auto indexing = makeCanonicalAffineApplies(
b, loc, indexedGenericOp.getInputIndexingMap(i), allIvs);
// Pass input i through IndexedValueType emits the proper load operation.
indexedValues.push_back(
IndexedValueType(indexedGenericOp.getInput(i))(indexing));
}
// 1.b. Emit load from output views.
for (unsigned i = 0; i < nOutputs; ++i) {
auto indexing = makeCanonicalAffineApplies(
b, loc, indexedGenericOp.getOutputIndexingMap(i), allIvs);
// Pass output i through IndexedValueType emits the proper load operation.
indexedValues.push_back(
IndexedValueType(indexedGenericOp.getOutputBuffer(i))(indexing));
}
// TODO: When a region inliner exists, use it.
// 2. Inline region, currently only works for a single basic block.
// 3. Emit store.
SmallVector<SmallVector<Value, 8>, 8> indexing;
SmallVector<Value, 8> outputBuffers;
for (unsigned i = 0; i < nOutputs; ++i) {
indexing.push_back(makeCanonicalAffineApplies(
b, loc, indexedGenericOp.getOutputIndexingMap(i), allIvs));
outputBuffers.push_back(indexedGenericOp.getOutputBuffer(i));
}
inlineRegionAndEmitStore<IndexedValueType>(indexedGenericOp, indexedValues,
indexing, outputBuffers);
}
template <typename LoopTy>
static Optional<LinalgLoops> linalgOpToLoopsImpl(Operation *op,
OpBuilder &builder) {
using IndexedValueTy = typename GenerateLoopNest<LoopTy>::IndexedValueTy;
ScopedContext scope(builder, op->getLoc());
// The flattened loopToOperandRangesMaps is expected to be an invertible
// permutation map (which is asserted in the inverse calculation).
auto linalgOp = cast<LinalgOp>(op);
assert(linalgOp.hasBufferSemantics() &&
"expected linalg op with buffer semantics");
auto loopRanges = linalgOp.createLoopRanges(builder, op->getLoc());
SmallVector<Value, 4> allIvs;
GenerateLoopNest<LoopTy>::doit(
loopRanges, /*iterInitArgs*/ {}, linalgOp.iterator_types().getValue(),
[&](ValueRange ivs, ValueRange iterArgs) -> scf::ValueVector {
assert(iterArgs.empty() && "unexpected iterArgs");
allIvs.append(ivs.begin(), ivs.end());
llvm::TypeSwitch<Operation *>(op)
.Case<CopyOp, FillOp, ConvOp, PoolingMaxOp, PoolingMinOp,
PoolingSumOp, IndexedGenericOp, LinalgOp>([&](auto op) {
emitScalarImplementation<IndexedValueTy>(allIvs, op);
})
.Default([&](Operation *op) { assert(false && "unexpected op"); });
return scf::ValueVector{};
});
// Number of loop ops might be different from the number of ivs since some
// loops like affine.parallel and scf.parallel have multiple ivs.
llvm::SetVector<Operation *> loopSet;
for (Value iv : allIvs) {
if (!iv)
return {};
// The induction variable is a block argument of the entry block of the
// loop operation.
BlockArgument ivVal = iv.dyn_cast<BlockArgument>();
if (!ivVal)
return {};
loopSet.insert(ivVal.getOwner()->getParentOp());
}
LinalgLoops loops(loopSet.begin(), loopSet.end());
return loops;
}
namespace {
template <typename LoopType>
class LinalgRewritePattern : public RewritePattern {
public:
LinalgRewritePattern() : RewritePattern(/*benefit=*/1, MatchAnyOpTypeTag()) {}
LogicalResult matchAndRewrite(Operation *op,
PatternRewriter &rewriter) const override {
if (!isa<LinalgOp>(op))
return failure();
if (!linalgOpToLoopsImpl<LoopType>(op, rewriter))
return failure();
rewriter.eraseOp(op);
return success();
}
};
struct FoldAffineOp;
} // namespace
template <typename LoopType>
static void lowerLinalgToLoopsImpl(FuncOp funcOp, MLIRContext *context) {
OwningRewritePatternList patterns;
patterns.insert<LinalgRewritePattern<LoopType>>();
DimOp::getCanonicalizationPatterns(patterns, context);
AffineApplyOp::getCanonicalizationPatterns(patterns, context);
patterns.insert<FoldAffineOp>(context);
// Just apply the patterns greedily.
applyPatternsAndFoldGreedily(funcOp, std::move(patterns));
}
namespace {
/// Local folding pattern for AffineApplyOp that we can apply greedily.
/// This replaces AffineApplyOp by the proper value in cases where the
/// associated map is trivial.
/// A trivial map here is defined as a map with a single result and either:
/// 1. Zero operand + returns a single AffineConstantExpr
/// 2. One operand + returns a single AffineDimExpr
/// 3. One operand + returns a single AffineSymbolExpr
//
/// In the first case, the AffineApplyOp is replaced by a new constant. In the
/// other cases, it is replaced by its unique operand.
struct FoldAffineOp : public RewritePattern {
FoldAffineOp(MLIRContext *context)
: RewritePattern(AffineApplyOp::getOperationName(), 0, context) {}
LogicalResult matchAndRewrite(Operation *op,
PatternRewriter &rewriter) const override {
AffineApplyOp affineApplyOp = cast<AffineApplyOp>(op);
auto map = affineApplyOp.getAffineMap();
if (map.getNumResults() != 1 || map.getNumInputs() > 1)
return failure();
AffineExpr expr = map.getResult(0);
if (map.getNumInputs() == 0) {
if (auto val = expr.dyn_cast<AffineConstantExpr>()) {
rewriter.replaceOpWithNewOp<ConstantIndexOp>(op, val.getValue());
return success();
}
return failure();
}
if (expr.dyn_cast<AffineDimExpr>() || expr.dyn_cast<AffineSymbolExpr>()) {
rewriter.replaceOp(op, op->getOperand(0));
return success();
}
return failure();
}
};
struct LowerToAffineLoops
: public LinalgLowerToAffineLoopsBase<LowerToAffineLoops> {
void runOnFunction() override {
lowerLinalgToLoopsImpl<AffineForOp>(getFunction(), &getContext());
}
};
struct LowerToLoops : public LinalgLowerToLoopsBase<LowerToLoops> {
void runOnFunction() override {
lowerLinalgToLoopsImpl<scf::ForOp>(getFunction(), &getContext());
}
};
struct LowerToParallelLoops
: public LinalgLowerToParallelLoopsBase<LowerToParallelLoops> {
void runOnFunction() override {
lowerLinalgToLoopsImpl<scf::ParallelOp>(getFunction(), &getContext());
}
};
} // namespace
std::unique_ptr<OperationPass<FuncOp>> mlir::createConvertLinalgToLoopsPass() {
return std::make_unique<LowerToLoops>();
}
std::unique_ptr<OperationPass<FuncOp>>
mlir::createConvertLinalgToParallelLoopsPass() {
return std::make_unique<LowerToParallelLoops>();
}
std::unique_ptr<OperationPass<FuncOp>>
mlir::createConvertLinalgToAffineLoopsPass() {
return std::make_unique<LowerToAffineLoops>();
}
/// Emits a loop nest with the proper body for `op`.
template <typename LoopTy>
Optional<LinalgLoops> mlir::linalg::linalgLowerOpToLoops(OpBuilder &builder,
Operation *op) {
return linalgOpToLoopsImpl<LoopTy>(op, builder);
}
template Optional<LinalgLoops>
mlir::linalg::linalgLowerOpToLoops<AffineForOp>(OpBuilder &builder,
Operation *op);
template Optional<LinalgLoops>
mlir::linalg::linalgLowerOpToLoops<scf::ForOp>(OpBuilder &builder,
Operation *op);
template Optional<LinalgLoops>
mlir::linalg::linalgLowerOpToLoops<scf::ParallelOp>(OpBuilder &builder,
Operation *op);
/// Emits a loop nest of `affine.for` with the proper body for `op`.
LogicalResult mlir::linalg::linalgOpToAffineLoops(OpBuilder &builder,
Operation *op) {
Optional<LinalgLoops> loops = linalgLowerOpToLoops<AffineForOp>(builder, op);
return loops ? success() : failure();
}
/// Emits a loop nest of `scf.for` with the proper body for `op`.
LogicalResult mlir::linalg::linalgOpToLoops(OpBuilder &builder, Operation *op) {
Optional<LinalgLoops> loops = linalgLowerOpToLoops<scf::ForOp>(builder, op);
return loops ? success() : failure();
}
/// Emits a loop nest of `scf.parallel` with the proper body for `op`.
LogicalResult mlir::linalg::linalgOpToParallelLoops(OpBuilder &builder,
Operation *op) {
Optional<LinalgLoops> loops =
linalgLowerOpToLoops<scf::ParallelOp>(builder, op);
return loops ? success() : failure();
}