2023-03-08 19:52:09 +00:00

1462 lines
63 KiB
C++

//===- SparseTensorCodegen.cpp - Sparse tensor primitives conversion ------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// A pass that converts sparse tensor types and primitives to actual compiler
// visible buffers and actual compiler IR that implements these primitives on
// the selected sparse tensor storage schemes. This pass provides an alternative
// to the SparseTensorConversion pass, eliminating the dependence on a runtime
// support library, and providing much more opportunities for subsequent
// compiler optimization of the generated code.
//
//===----------------------------------------------------------------------===//
#include "CodegenUtils.h"
#include "SparseTensorStorageLayout.h"
#include "mlir/Dialect/Bufferization/IR/Bufferization.h"
#include "mlir/Dialect/Func/IR/FuncOps.h"
#include "mlir/Dialect/Linalg/Utils/Utils.h"
#include "mlir/Dialect/MemRef/IR/MemRef.h"
#include "mlir/Dialect/SparseTensor/IR/Enums.h"
#include "mlir/Dialect/SparseTensor/IR/SparseTensor.h"
#include "mlir/Dialect/SparseTensor/IR/SparseTensorType.h"
#include "mlir/Dialect/SparseTensor/Transforms/Passes.h"
#include "mlir/Dialect/Tensor/IR/Tensor.h"
#include "mlir/Transforms/DialectConversion.h"
#include "llvm/Support/FormatVariadic.h"
#include <optional>
using namespace mlir;
using namespace mlir::sparse_tensor;
namespace {
using FuncGeneratorType =
function_ref<void(OpBuilder &, ModuleOp, func::FuncOp, RankedTensorType)>;
static constexpr const char kInsertFuncNamePrefix[] = "_insert_";
//===----------------------------------------------------------------------===//
// Helper methods.
//===----------------------------------------------------------------------===//
/// Flatten a list of operands that may contain sparse tensors.
static void flattenOperands(ValueRange operands,
SmallVectorImpl<Value> &flattened) {
// In case of
// sparse_tensor, c, sparse_tensor
// ==>
// memref ..., c, memref ...
for (auto operand : operands) {
if (getSparseTensorEncoding(operand.getType())) {
auto tuple = getTuple(operand);
// An unrealized_conversion_cast will be inserted by type converter to
// inter-mix the gap between 1:N conversion between sparse tensors and
// fields. In this case, take the operands in the cast and replace the
// sparse tensor output with the flattened type array.
flattened.append(tuple.getOperands().begin(), tuple.getOperands().end());
} else {
flattened.push_back(operand);
}
}
}
/// Generates a load with proper `index` typing.
static Value genLoad(OpBuilder &builder, Location loc, Value mem, Value idx) {
idx = genCast(builder, loc, idx, builder.getIndexType());
return builder.create<memref::LoadOp>(loc, mem, idx);
}
/// Generates a store with proper `index` typing and proper value.
static void genStore(OpBuilder &builder, Location loc, Value val, Value mem,
Value idx) {
idx = genCast(builder, loc, idx, builder.getIndexType());
val = genCast(builder, loc, val,
mem.getType().cast<ShapedType>().getElementType());
builder.create<memref::StoreOp>(loc, val, mem, idx);
}
/// Creates a straightforward counting for-loop.
static scf::ForOp createFor(OpBuilder &builder, Location loc, Value upper,
MutableArrayRef<Value> fields,
Value lower = Value()) {
Type indexType = builder.getIndexType();
if (!lower)
lower = constantZero(builder, loc, indexType);
Value one = constantOne(builder, loc, indexType);
scf::ForOp forOp = builder.create<scf::ForOp>(loc, lower, upper, one, fields);
for (unsigned i = 0, e = fields.size(); i < e; i++)
fields[i] = forOp.getRegionIterArg(i);
builder.setInsertionPointToStart(forOp.getBody());
return forOp;
}
/// Gets the dimension size for the given sparse tensor at the given
/// original dimension 'dim'.
static Value sizeFromTensorAtDim(OpBuilder &builder, Location loc,
SparseTensorDescriptor desc, Dimension dim) {
const SparseTensorType stt(desc.getRankedTensorType());
// Access into static dimension can query original type directly.
// Note that this is typically already done by DimOp's folding.
if (auto sz = stt.getStaticDimSize(dim))
return constantIndex(builder, loc, *sz);
// Any other query can consult the dimSizes array at field DimSizesIdx,
// accounting for the reordering applied to the sparse storage.
// FIXME: `toStoredDim` is deprecated.
const Level lvl = toStoredDim(stt, dim);
return desc.getLvlSize(builder, loc, lvl);
}
// Gets the dimension size at the given stored level 'lvl', either as a
// constant for a static size, or otherwise dynamically through memSizes.
static Value sizeFromTensorAtLvl(OpBuilder &builder, Location loc,
SparseTensorDescriptor desc, Level lvl) {
// FIXME: `toOrigDim` is deprecated.
return sizeFromTensorAtDim(builder, loc, desc,
toOrigDim(desc.getRankedTensorType(), lvl));
}
static void createPushback(OpBuilder &builder, Location loc,
MutSparseTensorDescriptor desc,
SparseTensorFieldKind kind, std::optional<Level> lvl,
Value value, Value repeat = Value()) {
Type etp = desc.getMemRefElementType(kind, lvl);
Value field = desc.getMemRefField(kind, lvl);
StorageSpecifierKind specFieldKind = toSpecifierKind(kind);
auto pushBackOp = builder.create<PushBackOp>(
loc, desc.getSpecifierField(builder, loc, specFieldKind, lvl), field,
genCast(builder, loc, value, etp), repeat);
desc.setMemRefField(kind, lvl, pushBackOp.getOutBuffer());
desc.setSpecifierField(builder, loc, specFieldKind, lvl,
pushBackOp.getNewSize());
}
/// Generates code that allocates a sparse storage scheme for given rank.
static void allocSchemeForRank(OpBuilder &builder, Location loc,
MutSparseTensorDescriptor desc, Level startLvl) {
const SparseTensorType stt(desc.getRankedTensorType());
Value linear = constantIndex(builder, loc, 1);
const Level lvlRank = stt.getLvlRank();
for (Level l = startLvl; l < lvlRank; l++) {
const auto dlt = stt.getLvlType(l);
if (isCompressedDLT(dlt)) {
// Append linear x positions, initialized to zero. Since each compressed
// dimension initially already has a single zero entry, this maintains
// the desired "linear + 1" length property at all times.
Value posZero = constantZero(builder, loc, stt.getPosType());
createPushback(builder, loc, desc, SparseTensorFieldKind::PosMemRef, l,
posZero, linear);
return;
}
if (isSingletonDLT(dlt)) {
return; // nothing to do
}
// Keep compounding the size, but nothing needs to be initialized
// at this level. We will eventually reach a compressed level or
// otherwise the values array for the from-here "all-dense" case.
assert(isDenseDLT(dlt));
Value size = sizeFromTensorAtLvl(builder, loc, desc, l);
linear = builder.create<arith::MulIOp>(loc, linear, size);
}
// Reached values array so prepare for an insertion.
Value valZero = constantZero(builder, loc, stt.getElementType());
createPushback(builder, loc, desc, SparseTensorFieldKind::ValMemRef,
std::nullopt, valZero, linear);
}
/// Creates allocation operation.
static Value createAllocation(OpBuilder &builder, Location loc,
MemRefType memRefType, Value sz,
bool enableInit) {
Value buffer = builder.create<memref::AllocOp>(loc, memRefType, sz);
Type elemType = memRefType.getElementType();
if (enableInit) {
Value fillValue = constantZero(builder, loc, elemType);
builder.create<linalg::FillOp>(loc, fillValue, buffer);
}
return buffer;
}
/// Creates allocation for each field in sparse tensor type. Note that
/// for all dynamic memrefs, the memory size is really the capacity of
/// the "vector", while the actual size resides in the sizes array.
///
/// TODO: for efficiency, we will need heuristics to make educated guesses
/// on the required capacities (see heuristic variable).
///
static void createAllocFields(OpBuilder &builder, Location loc,
SparseTensorType stt, ValueRange dynSizes,
bool enableInit, SmallVectorImpl<Value> &fields,
Value sizeHint) {
// Build original sizes.
assert((dynSizes.size() == static_cast<size_t>(stt.getNumDynamicDims())) &&
"Got wrong number of dynamic sizes");
const Dimension dimRank = stt.getDimRank();
SmallVector<Value> dimSizes;
dimSizes.reserve(dimRank);
unsigned i = 0; // cumulative index into `dynSizes`.
for (const DynSize sh : stt.getDimShape())
dimSizes.push_back(ShapedType::isDynamic(sh)
? dynSizes[i++]
: constantIndex(builder, loc, sh));
// Set up some heuristic sizes. We try to set the initial
// size based on available information. Otherwise we just
// initialize a few elements to start the reallocation chain.
// TODO: refine this
Value posHeuristic, crdHeuristic, valHeuristic;
if (stt.isAllDense()) {
valHeuristic = dimSizes[0];
for (const Value sz : ArrayRef<Value>{dimSizes}.drop_front())
valHeuristic = builder.create<arith::MulIOp>(loc, valHeuristic, sz);
} else if (sizeHint) {
if (getCOOStart(stt.getEncoding()) == 0) {
posHeuristic = constantIndex(builder, loc, 2);
crdHeuristic = builder.create<arith::MulIOp>(
loc, constantIndex(builder, loc, dimRank), sizeHint); // AOS
} else if (dimRank == 2 && stt.isDenseLvl(0) && stt.isCompressedLvl(1)) {
posHeuristic = builder.create<arith::AddIOp>(
loc, sizeHint, constantIndex(builder, loc, 1));
crdHeuristic = sizeHint;
} else {
posHeuristic = crdHeuristic = constantIndex(builder, loc, 16);
}
valHeuristic = sizeHint;
} else {
posHeuristic = crdHeuristic = valHeuristic =
constantIndex(builder, loc, 16);
}
foreachFieldAndTypeInSparseTensor(
stt,
[&builder, &fields, stt, loc, posHeuristic, crdHeuristic, valHeuristic,
enableInit](Type fType, FieldIndex fIdx, SparseTensorFieldKind fKind,
Level /*lvl*/, DimLevelType /*dlt*/) -> bool {
assert(fields.size() == fIdx);
Value field;
switch (fKind) {
case SparseTensorFieldKind::StorageSpec:
field = SparseTensorSpecifier::getInitValue(builder, loc, stt);
break;
case SparseTensorFieldKind::PosMemRef:
case SparseTensorFieldKind::CrdMemRef:
case SparseTensorFieldKind::ValMemRef:
field = createAllocation(
builder, loc, fType.cast<MemRefType>(),
(fKind == SparseTensorFieldKind::PosMemRef) ? posHeuristic
: (fKind == SparseTensorFieldKind::CrdMemRef) ? crdHeuristic
: valHeuristic,
enableInit);
break;
}
assert(field);
fields.push_back(field);
// Returns true to continue the iteration.
return true;
});
MutSparseTensorDescriptor desc(stt, fields);
// Initialize the storage scheme to an empty tensor. Initialized memSizes
// to all zeros, sets the dimSizes to known values and gives all position
// fields an initial zero entry, so that it is easier to maintain the
// "linear + 1" length property.
Value posZero = constantZero(builder, loc, stt.getPosType());
for (Level lvlRank = stt.getLvlRank(), l = 0; l < lvlRank; l++) {
// Fills dim sizes array.
// FIXME: `toOrigDim` is deprecated.
desc.setLvlSize(builder, loc, l, dimSizes[toOrigDim(stt, l)]);
// Pushes a leading zero to positions memref.
if (stt.isCompressedLvl(l))
createPushback(builder, loc, desc, SparseTensorFieldKind::PosMemRef, l,
posZero);
}
allocSchemeForRank(builder, loc, desc, /*rank=*/0);
}
/// Helper method that generates block specific to compressed case:
///
/// // given: parentPos = posCursor[lvl-1]
/// pstart = desc.positions[lvl][parentPos]
/// pstop = desc.positions[lvl][parentPos+1]
/// plast = pstop - 1
/// msz = desc.coordinates[lvl].size()
/// if (pstart < pstop) {
/// isPresent = (desc.coordinates[lvl][plast] == lvlCoords[lvl])
/// } else { // first insertion
/// isPresent = false
/// desc.positions[lvl][parentPos] = msz
/// }
/// if (isPresent) { // coordinate is already present
/// pnext = plast
/// } else {
/// desc.coordinates[lvl].push_back(lvlCoords[lvl])
/// desc.positions[lvl][parentPos+1] = msz+1
/// pnext = msz
/// <prepare level lvl+1>
/// }
/// posCursor[lvl] = pnext
static Value genCompressed(OpBuilder &builder, Location loc,
MutSparseTensorDescriptor desc, ValueRange lvlCoords,
Value /*unused*/, Value parentPos, Level lvl) {
const SparseTensorType stt(desc.getRankedTensorType());
const Level lvlRank = stt.getLvlRank();
assert(lvl < lvlRank && "Level is out of bounds");
assert(lvlCoords.size() == static_cast<size_t>(lvlRank) &&
"Level-rank mismatch");
SmallVector<Type> types;
Type indexType = builder.getIndexType();
Type boolType = builder.getIntegerType(1);
unsigned crdFidx;
unsigned crdStride;
std::tie(crdFidx, crdStride) = desc.getCrdMemRefIndexAndStride(lvl);
const Value one = constantIndex(builder, loc, 1);
const Value pp1 = builder.create<arith::AddIOp>(loc, parentPos, one);
const Value positionsAtLvl = desc.getPosMemRef(lvl);
const Value pstart = genLoad(builder, loc, positionsAtLvl, parentPos);
const Value pstop = genLoad(builder, loc, positionsAtLvl, pp1);
const Value crdMsz = desc.getCrdMemSize(builder, loc, lvl);
const Value crdStrideC =
crdStride > 1 ? constantIndex(builder, loc, crdStride) : Value();
const Value msz =
crdStrideC ? builder.create<arith::DivUIOp>(loc, crdMsz, crdStrideC)
: crdMsz;
const Value plast = builder.create<arith::SubIOp>(
loc, genCast(builder, loc, pstop, indexType), one);
// Conditional expression.
Value lt = builder.create<arith::CmpIOp>(loc, arith::CmpIPredicate::ult,
pstart, pstop);
types.push_back(boolType);
scf::IfOp ifOp1 = builder.create<scf::IfOp>(loc, types, lt, /*else*/ true);
types.pop_back();
builder.setInsertionPointToStart(&ifOp1.getThenRegion().front());
Value crd =
genLoad(builder, loc, desc.getMemRefField(crdFidx),
crdStrideC ? builder.create<arith::MulIOp>(loc, plast, crdStrideC)
: plast);
Value eq = builder.create<arith::CmpIOp>(
loc, arith::CmpIPredicate::eq, genCast(builder, loc, crd, indexType),
lvlCoords[lvl]);
builder.create<scf::YieldOp>(loc, eq);
builder.setInsertionPointToStart(&ifOp1.getElseRegion().front());
if (lvl > 0)
genStore(builder, loc, msz, positionsAtLvl, parentPos);
builder.create<scf::YieldOp>(loc, constantI1(builder, loc, false));
builder.setInsertionPointAfter(ifOp1);
// If present construct. Note that for a non-unique dimension level, we
// simply set the condition to false and rely on CSE/DCE to clean up the IR.
//
// TODO: generate less temporary IR?
//
for (unsigned i = 0, e = desc.getNumFields(); i < e; i++)
types.push_back(desc.getField(i).getType());
types.push_back(indexType);
const Value p = stt.isUniqueLvl(lvl) ? ifOp1.getResult(0)
: constantI1(builder, loc, false);
scf::IfOp ifOp2 = builder.create<scf::IfOp>(loc, types, p, /*else*/ true);
// If present (fields unaffected, update pnext to plast).
builder.setInsertionPointToStart(&ifOp2.getThenRegion().front());
// FIXME: This does not looks like a clean way, but probably the most
// efficient way.
desc.getFields().push_back(plast);
builder.create<scf::YieldOp>(loc, desc.getFields());
desc.getFields().pop_back();
// If !present (changes fields, update pnext).
builder.setInsertionPointToStart(&ifOp2.getElseRegion().front());
Value mszp1 = builder.create<arith::AddIOp>(loc, msz, one);
genStore(builder, loc, mszp1, positionsAtLvl, pp1);
createPushback(builder, loc, desc, SparseTensorFieldKind::CrdMemRef, lvl,
lvlCoords[lvl]);
// Prepare the next level "as needed".
if ((lvl + 1) < lvlRank)
allocSchemeForRank(builder, loc, desc, lvl + 1);
desc.getFields().push_back(msz);
builder.create<scf::YieldOp>(loc, desc.getFields());
desc.getFields().pop_back();
// Update fields and return next pos.
builder.setInsertionPointAfter(ifOp2);
unsigned o = 0;
for (unsigned i = 0, e = desc.getNumFields(); i < e; i++)
desc.setField(i, ifOp2.getResult(o++));
return ifOp2.getResult(o);
}
/// Generates code along an insertion path without the need for a "cursor".
/// This current insertion strategy comes at the expense of some testing
/// overhead for each insertion. The strategy will be optimized later for
/// common insertion patterns. The current insertion strategy also assumes
/// insertions occur in "a reasonable order" that enables building the
/// storage scheme in an appending/inserting kind of fashion (i.e. no
/// in-between insertions that need data movement). The implementation
/// relies on CSE/DCE to clean up all bookkeeping that is not needed.
///
/// TODO: better unord/not-unique; also generalize, optimize, specialize!
///
static void genInsertBody(OpBuilder &builder, ModuleOp module,
func::FuncOp func, RankedTensorType rtp) {
const OpBuilder::InsertionGuard insertionGuard(builder);
Block *const entryBlock = func.addEntryBlock();
builder.setInsertionPointToStart(entryBlock);
const ValueRange args = entryBlock->getArguments();
const Location loc = func.getLoc();
const SparseTensorType stt(rtp);
const Level lvlRank = stt.getLvlRank();
// Extract fields and coordinates from args.
SmallVector<Value> fields = llvm::to_vector(args.drop_back(lvlRank + 1));
MutSparseTensorDescriptor desc(rtp, fields);
const SmallVector<Value> coordinates =
llvm::to_vector(args.take_back(lvlRank + 1).drop_back());
Value value = args.back();
Value parentPos = constantZero(builder, loc, builder.getIndexType());
// Generate code for every level.
for (Level l = 0; l < lvlRank; l++) {
const auto dlt = stt.getLvlType(l);
if (isCompressedDLT(dlt)) {
// Create:
// if (!present) {
// coordinates[l].push_back(coords[l])
// <update positions and prepare level l + 1>
// }
// positions[l] = coordinates.size() - 1
// <insert @ positions[l] at next level l + 1>
parentPos =
genCompressed(builder, loc, desc, coordinates, value, parentPos, l);
} else if (isSingletonDLT(dlt)) {
// Create:
// coordinates[l].push_back(coords[l])
// positions[l] = positions[l-1]
// <insert @ positions[l] at next level l + 1>
createPushback(builder, loc, desc, SparseTensorFieldKind::CrdMemRef, l,
coordinates[l]);
} else {
assert(isDenseDLT(dlt));
// Construct the new position as:
// positions[l] = size * positions[l-1] + coords[l]
// <insert @ positions[l] at next level l + 1>
Value size = sizeFromTensorAtLvl(builder, loc, desc, l);
Value mult = builder.create<arith::MulIOp>(loc, size, parentPos);
parentPos = builder.create<arith::AddIOp>(loc, mult, coordinates[l]);
}
}
// Reached the actual value append/insert.
if (!stt.isDenseLvl(lvlRank - 1))
createPushback(builder, loc, desc, SparseTensorFieldKind::ValMemRef,
std::nullopt, value);
else
genStore(builder, loc, value, desc.getValMemRef(), parentPos);
builder.create<func::ReturnOp>(loc, fields);
}
/// Generates a call to a function to perform an insertion operation. If the
/// function doesn't exist yet, call `createFunc` to generate the function.
static void genInsertionCallHelper(OpBuilder &builder,
MutSparseTensorDescriptor desc,
SmallVectorImpl<Value> &lcvs, Value value,
func::FuncOp insertPoint,
StringRef namePrefix,
FuncGeneratorType createFunc) {
// The mangled name of the function has this format:
// <namePrefix>_<DLT>_<shape>_<ordering>_<eltType>_<crdWidth>_<posWidth>
const SparseTensorType stt(desc.getRankedTensorType());
SmallString<32> nameBuffer;
llvm::raw_svector_ostream nameOstream(nameBuffer);
nameOstream << namePrefix;
const Level lvlRank = stt.getLvlRank();
assert(lcvs.size() == static_cast<size_t>(lvlRank));
for (Level l = 0; l < lvlRank; l++)
nameOstream << toMLIRString(stt.getLvlType(l)) << "_";
// Static dim sizes are used in the generated code while dynamic sizes are
// loaded from the dimSizes buffer. This is the reason for adding the shape
// to the function name.
for (const auto sh : stt.getDimShape())
nameOstream << sh << "_";
// Permutation information is also used in generating insertion.
if (!stt.isIdentity())
nameOstream << stt.getDimToLvlMap() << "_";
nameOstream << stt.getElementType() << "_";
nameOstream << stt.getCrdWidth() << "_" << stt.getPosWidth();
// Look up the function.
ModuleOp module = insertPoint->getParentOfType<ModuleOp>();
MLIRContext *context = module.getContext();
auto result = SymbolRefAttr::get(context, nameOstream.str());
auto func = module.lookupSymbol<func::FuncOp>(result.getAttr());
// Construct operands: fields, coords, and value.
SmallVector<Value> operands = llvm::to_vector(desc.getFields());
operands.append(lcvs);
operands.push_back(value);
Location loc = insertPoint.getLoc();
if (!func) {
// Create the function.
OpBuilder::InsertionGuard insertionGuard(builder);
builder.setInsertionPoint(insertPoint);
func = builder.create<func::FuncOp>(
loc, nameOstream.str(),
FunctionType::get(context, ValueRange(operands).getTypes(),
ValueRange(desc.getFields()).getTypes()));
func.setPrivate();
createFunc(builder, module, func, stt);
}
// Generate a call to perform the insertion and update `fields` with values
// returned from the call.
func::CallOp call = builder.create<func::CallOp>(loc, func, operands);
for (size_t i = 0, e = desc.getNumFields(); i < e; i++) {
desc.getFields()[i] = call.getResult(i);
}
}
/// Generations insertion finalization code.
static void genEndInsert(OpBuilder &builder, Location loc,
SparseTensorDescriptor desc) {
const SparseTensorType stt(desc.getRankedTensorType());
const Level lvlRank = stt.getLvlRank();
for (Level l = 0; l < lvlRank; l++) {
const auto dlt = stt.getLvlType(l);
if (isCompressedDLT(dlt)) {
// Compressed dimensions need a position cleanup for all entries
// that were not visited during the insertion pass.
//
// TODO: avoid cleanup and keep compressed scheme consistent at all
// times?
//
if (l > 0) {
Type posType = stt.getPosType();
Value posMemRef = desc.getPosMemRef(l);
Value hi = desc.getPosMemSize(builder, loc, l);
Value zero = constantIndex(builder, loc, 0);
Value one = constantIndex(builder, loc, 1);
// Vector of only one, but needed by createFor's prototype.
SmallVector<Value, 1> inits{genLoad(builder, loc, posMemRef, zero)};
scf::ForOp loop = createFor(builder, loc, hi, inits, one);
Value i = loop.getInductionVar();
Value oldv = loop.getRegionIterArg(0);
Value newv = genLoad(builder, loc, posMemRef, i);
Value posZero = constantZero(builder, loc, posType);
Value cond = builder.create<arith::CmpIOp>(
loc, arith::CmpIPredicate::eq, newv, posZero);
scf::IfOp ifOp = builder.create<scf::IfOp>(loc, TypeRange(posType),
cond, /*else*/ true);
builder.setInsertionPointToStart(&ifOp.getThenRegion().front());
genStore(builder, loc, oldv, posMemRef, i);
builder.create<scf::YieldOp>(loc, oldv);
builder.setInsertionPointToStart(&ifOp.getElseRegion().front());
builder.create<scf::YieldOp>(loc, newv);
builder.setInsertionPointAfter(ifOp);
builder.create<scf::YieldOp>(loc, ifOp.getResult(0));
builder.setInsertionPointAfter(loop);
}
} else {
assert(isDenseDLT(dlt) || isSingletonDLT(dlt));
}
}
}
/// Returns a memref that fits the requested length (reallocates if requested
/// length is larger, or creates a subview if it is smaller).
static Value reallocOrSubView(OpBuilder &builder, Location loc, int64_t len,
Value buffer) {
MemRefType memTp = getMemRefType(buffer);
auto retTp = MemRefType::get(ArrayRef{len}, memTp.getElementType());
Value targetLen = constantIndex(builder, loc, len);
Value bufferLen = linalg::createOrFoldDimOp(builder, loc, buffer, 0);
// Reallocates if target length is greater than the actual buffer len.
Value reallocP = builder.create<arith::CmpIOp>(loc, arith::CmpIPredicate::ugt,
targetLen, bufferLen);
scf::IfOp ifOp = builder.create<scf::IfOp>(loc, retTp, reallocP, true);
// If targetLen > bufferLen, reallocate to get enough sparse to return.
builder.setInsertionPointToStart(&ifOp.getThenRegion().front());
Value reallocBuf = builder.create<memref::ReallocOp>(loc, retTp, buffer);
builder.create<scf::YieldOp>(loc, reallocBuf);
// Else, return a subview to fit the size.
builder.setInsertionPointToStart(&ifOp.getElseRegion().front());
Value subViewBuf = builder.create<memref::SubViewOp>(
loc, retTp, buffer, /*offset=*/ArrayRef<int64_t>{0},
/*size=*/ArrayRef<int64_t>{len},
/*stride=*/ArrayRef<int64_t>{1});
builder.create<scf::YieldOp>(loc, subViewBuf);
// Resets insertion point.
builder.setInsertionPointAfter(ifOp);
return ifOp.getResult(0);
}
//===----------------------------------------------------------------------===//
// Codegen rules.
//===----------------------------------------------------------------------===//
/// Sparse tensor storage conversion rule for returns.
class SparseReturnConverter : public OpConversionPattern<func::ReturnOp> {
public:
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(func::ReturnOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
SmallVector<Value> flattened;
flattenOperands(adaptor.getOperands(), flattened);
// Create a return with the flattened value extracted from sparse tensors.
rewriter.replaceOpWithNewOp<func::ReturnOp>(op, flattened);
return success();
}
};
/// Sparse tensor storage conversion rule for calls.
class SparseCallConverter : public OpConversionPattern<func::CallOp> {
public:
// The default CallOp converter can not handle 1:N type conversion.
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(func::CallOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
Location loc = op.getLoc();
// In case of:
// sparse_tensor, f, sparse_tensor = call @foo(...)
// ==>
// memref..., f, memref = call @foo(...) replace with
// cast(memref...)->sparse_tensor, f, cast(memref...)->sparse_tensor
SmallVector<Type> finalRetTy;
if (failed(typeConverter->convertTypes(op.getResultTypes(), finalRetTy)))
return failure();
// (1) Genereates new call with flattened return value.
SmallVector<Value> flattened;
flattenOperands(adaptor.getOperands(), flattened);
auto newCall = rewriter.create<func::CallOp>(loc, op.getCallee(),
finalRetTy, flattened);
// (2) Create cast operation for sparse tensor returns.
SmallVector<Value> castedRet;
// Tracks the offset of current return value (of the orignal call)
// relative to the new call (after sparse tensor flattening);
unsigned retOffset = 0;
// Temporal buffer to hold the flattened list of type for
// a sparse tensor.
SmallVector<Type> sparseFlat;
for (auto ret : op.getResults()) {
assert(retOffset < newCall.getNumResults());
auto retType = ret.getType();
if (failed(typeConverter->convertType(retType, sparseFlat)))
// This should never happen.
llvm_unreachable("Failed to convert type in sparse tensor codegen");
// Converted types can not be empty when the type conversion succeed.
assert(!sparseFlat.empty());
if (sparseFlat.size() > 1) {
auto flatSize = sparseFlat.size();
ValueRange fields(iterator_range<ResultRange::iterator>(
newCall.result_begin() + retOffset,
newCall.result_begin() + retOffset + flatSize));
castedRet.push_back(genTuple(rewriter, loc, retType, fields));
retOffset += flatSize;
} else {
// If this is an 1:1 conversion, no need for casting.
castedRet.push_back(newCall.getResult(retOffset));
retOffset++;
}
sparseFlat.clear();
}
assert(castedRet.size() == op.getNumResults());
rewriter.replaceOp(op, castedRet);
return success();
}
};
/// Sparse codegen rule for dimension accesses.
class SparseDimOpConverter : public OpConversionPattern<tensor::DimOp> {
public:
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(tensor::DimOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
std::optional<int64_t> dim = op.getConstantIndex();
if (!dim || !getSparseTensorEncoding(adaptor.getSource().getType()))
return failure();
auto desc = getDescriptorFromTensorTuple(adaptor.getSource());
auto sz = sizeFromTensorAtDim(rewriter, op.getLoc(), desc, *dim);
rewriter.replaceOp(op, sz);
return success();
}
};
/// Sparse codegen rule for trivial tensor casts.
class SparseCastConverter : public OpConversionPattern<tensor::CastOp> {
public:
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(tensor::CastOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
// Only rewrite identically annotated source/dest.
auto encDst = getSparseTensorEncoding(op.getType());
auto encSrc = getSparseTensorEncoding(op.getSource().getType());
if (!encDst || encDst != encSrc)
return failure();
rewriter.replaceOp(op, adaptor.getOperands());
return success();
}
};
/// Sparse codgen rule for the alloc operator.
class SparseTensorAllocConverter
: public OpConversionPattern<bufferization::AllocTensorOp> {
public:
using OpConversionPattern::OpConversionPattern;
SparseTensorAllocConverter(TypeConverter &typeConverter, MLIRContext *context,
bool enableInit)
: OpConversionPattern(typeConverter, context),
enableBufferInitialization(enableInit) {}
LogicalResult
matchAndRewrite(bufferization::AllocTensorOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
const auto resType = getSparseTensorType(op);
if (!resType.hasEncoding())
return failure();
if (op.getCopy())
return rewriter.notifyMatchFailure(op, "tensor copy not implemented");
// Construct allocation for each field.
const Location loc = op.getLoc();
const Value sizeHint = op.getSizeHint();
const ValueRange dynSizes = adaptor.getDynamicSizes();
const size_t found = dynSizes.size();
const int64_t expected = resType.getNumDynamicDims();
if (found != static_cast<size_t>(expected))
return rewriter.notifyMatchFailure(
op, llvm::formatv(
"Got wrong number of dynamic sizes: Found={0}, Expected={1}",
found, expected));
SmallVector<Value> fields;
createAllocFields(rewriter, loc, resType, dynSizes,
enableBufferInitialization, fields, sizeHint);
// Replace operation with resulting memrefs.
rewriter.replaceOp(op, genTuple(rewriter, loc, resType, fields));
return success();
}
private:
bool enableBufferInitialization;
};
/// Sparse codegen rule for the dealloc operator.
class SparseTensorDeallocConverter
: public OpConversionPattern<bufferization::DeallocTensorOp> {
public:
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(bufferization::DeallocTensorOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
auto enc = getSparseTensorEncoding(op.getTensor().getType());
if (!enc)
return failure();
// Replace the sparse tensor deallocation with field deallocations.
Location loc = op.getLoc();
auto desc = getDescriptorFromTensorTuple(adaptor.getTensor());
for (auto input : desc.getMemRefFields())
// Deallocate every buffer used to store the sparse tensor handler.
rewriter.create<memref::DeallocOp>(loc, input);
rewriter.eraseOp(op);
return success();
}
};
/// Sparse codegen rule for tensor rematerialization.
class SparseTensorLoadConverter : public OpConversionPattern<LoadOp> {
public:
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(LoadOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
// Prepare descriptor.
auto desc = getDescriptorFromTensorTuple(adaptor.getTensor());
// Generate optional insertion finalization code.
if (op.getHasInserts())
genEndInsert(rewriter, op.getLoc(), desc);
// Replace operation with resulting memrefs.
rewriter.replaceOp(op, genTuple(rewriter, op.getLoc(), desc));
return success();
}
};
/// Sparse codegen rule for the expand op.
class SparseExpandConverter : public OpConversionPattern<ExpandOp> {
public:
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(ExpandOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
if (!getSparseTensorEncoding(op.getTensor().getType()))
return failure();
Location loc = op->getLoc();
auto desc = getDescriptorFromTensorTuple(adaptor.getTensor());
const auto srcType = getSparseTensorType(op.getTensor());
Type eltType = srcType.getElementType();
Type boolType = rewriter.getIntegerType(1);
Type idxType = rewriter.getIndexType();
// All initialization should be done on entry of the loop nest.
rewriter.setInsertionPointAfter(op.getTensor().getDefiningOp());
// Determine the size for access expansion (always the innermost stored
// dimension size, translated back to original dimension). Note that we
// recursively rewrite the new DimOp on the **original** tensor.
// FIXME: `toOrigDim` is deprecated.
const Dimension innerDim = toOrigDim(srcType, srcType.getLvlRank() - 1);
const auto sz = sizeFromTensorAtDim(rewriter, loc, desc, innerDim);
// Generate a memref for `sz` elements of type `t`.
const auto genAlloc = [&](Type t) {
const auto memTp = MemRefType::get({ShapedType::kDynamic}, t);
return rewriter.create<memref::AllocOp>(loc, memTp, ValueRange{sz});
};
// Allocate temporary buffers for values/filled-switch and added.
// We do not use stack buffers for this, since the expanded size may
// be rather large (as it envelops a single expanded dense dimension).
Value values = genAlloc(eltType);
Value filled = genAlloc(boolType);
Value added = genAlloc(idxType);
Value zero = constantZero(rewriter, loc, idxType);
// Reset the values/filled-switch to all-zero/false. Note that this
// introduces an O(N) operation into the computation, but this reset
// operation is amortized over the innermost loops for the access
// pattern expansion. As noted in the operation doc, we would like
// to amortize this setup cost even between kernels.
rewriter.create<linalg::FillOp>(
loc, ValueRange{constantZero(rewriter, loc, eltType)},
ValueRange{values});
rewriter.create<linalg::FillOp>(
loc, ValueRange{constantZero(rewriter, loc, boolType)},
ValueRange{filled});
// Replace expansion op with these buffers and initial coordinate.
assert(op.getNumResults() == 4);
rewriter.replaceOp(op, {values, filled, added, zero});
return success();
}
};
/// Sparse codegen rule for the compress operator.
class SparseCompressConverter : public OpConversionPattern<CompressOp> {
public:
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(CompressOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
Location loc = op->getLoc();
SmallVector<Value> fields;
auto desc = getMutDescriptorFromTensorTuple(adaptor.getTensor(), fields);
Value values = adaptor.getValues();
Value filled = adaptor.getFilled();
Value added = adaptor.getAdded();
Value count = adaptor.getCount();
const SparseTensorType dstType(desc.getRankedTensorType());
Type eltType = dstType.getElementType();
// Prepare level-coords.
SmallVector<Value> lcvs(adaptor.getLvlCoords());
// If the innermost level is ordered, we need to sort the coordinates
// in the "added" array prior to applying the compression.
if (dstType.isOrderedLvl(dstType.getLvlRank() - 1))
rewriter.create<SortOp>(loc, count, ValueRange{added}, ValueRange{},
SparseTensorSortKind::HybridQuickSort);
// While performing the insertions, we also need to reset the elements
// of the values/filled-switch by only iterating over the set elements,
// to ensure that the runtime complexity remains proportional to the
// sparsity of the expanded access pattern.
//
// Generate
// out_memrefs = for (i = 0; i < count; i++)(in_memrefs) {
// crd = added[i];
// value = values[crd];
// insert({lvlCoords, crd}, value);
// new_memrefs = insert(in_memrefs, {lvlCoords, crd}, value);
// values[crd] = 0;
// filled[crd] = false;
// yield new_memrefs
// }
scf::ForOp loop = createFor(rewriter, loc, count, desc.getFields());
Value i = loop.getInductionVar();
Value crd = genLoad(rewriter, loc, added, i);
Value value = genLoad(rewriter, loc, values, crd);
lcvs.push_back(crd);
// TODO: faster for subsequent insertions?
auto insertPoint = op->template getParentOfType<func::FuncOp>();
genInsertionCallHelper(rewriter, desc, lcvs, value, insertPoint,
kInsertFuncNamePrefix, genInsertBody);
genStore(rewriter, loc, constantZero(rewriter, loc, eltType), values, crd);
genStore(rewriter, loc, constantI1(rewriter, loc, false), filled, crd);
rewriter.create<scf::YieldOp>(loc, desc.getFields());
rewriter.setInsertionPointAfter(loop);
Value result = genTuple(rewriter, loc, dstType, loop->getResults());
// Deallocate the buffers on exit of the full loop nest.
Operation *parent = getTop(op);
rewriter.setInsertionPointAfter(parent);
rewriter.create<memref::DeallocOp>(loc, values);
rewriter.create<memref::DeallocOp>(loc, filled);
rewriter.create<memref::DeallocOp>(loc, added);
// Replace operation with resulting memrefs.
rewriter.replaceOp(op, result);
return success();
}
};
/// Sparse codegen rule for the insert operator.
class SparseInsertConverter : public OpConversionPattern<InsertOp> {
public:
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(InsertOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
SmallVector<Value> fields;
auto desc = getMutDescriptorFromTensorTuple(adaptor.getTensor(), fields);
SmallVector<Value> lcvs(adaptor.getLvlCoords());
// Generate insertion.
Value value = adaptor.getValue();
auto insertPoint = op->template getParentOfType<func::FuncOp>();
genInsertionCallHelper(rewriter, desc, lcvs, value, insertPoint,
kInsertFuncNamePrefix, genInsertBody);
// Replace operation with resulting memrefs.
rewriter.replaceOp(op, genTuple(rewriter, op.getLoc(), desc));
return success();
}
};
/// Sparse codegen rule for position accesses.
class SparseToPositionsConverter : public OpConversionPattern<ToPositionsOp> {
public:
using OpAdaptor = typename ToPositionsOp::Adaptor;
using OpConversionPattern<ToPositionsOp>::OpConversionPattern;
LogicalResult
matchAndRewrite(ToPositionsOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
// Replace the requested position access with corresponding field.
// The cast_op is inserted by type converter to intermix 1:N type
// conversion.
auto desc = getDescriptorFromTensorTuple(adaptor.getTensor());
rewriter.replaceOp(op, desc.getPosMemRef(op.getLevel()));
return success();
}
};
/// Sparse codegen rule for accessing the coordinates arrays.
class SparseToCoordinatesConverter
: public OpConversionPattern<ToCoordinatesOp> {
public:
using OpAdaptor = typename ToCoordinatesOp::Adaptor;
using OpConversionPattern<ToCoordinatesOp>::OpConversionPattern;
LogicalResult
matchAndRewrite(ToCoordinatesOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
// Replace the requested coordinates access with corresponding field.
// The cast_op is inserted by type converter to intermix 1:N type
// conversion.
Location loc = op.getLoc();
auto desc = getDescriptorFromTensorTuple(adaptor.getTensor());
Value field = desc.getCrdMemRefOrView(rewriter, loc, op.getLevel());
// Insert a cast to bridge the actual type to the user expected type. If the
// actual type and the user expected type aren't compatible, the compiler or
// the runtime will issue an error.
Type resType = op.getResult().getType();
if (resType != field.getType())
field = rewriter.create<memref::CastOp>(loc, resType, field);
rewriter.replaceOp(op, field);
return success();
}
};
/// Sparse codegen rule for accessing the linear coordinates buffer.
class SparseToCoordinatesBufferConverter
: public OpConversionPattern<ToCoordinatesBufferOp> {
public:
using OpAdaptor = typename ToCoordinatesBufferOp::Adaptor;
using OpConversionPattern<ToCoordinatesBufferOp>::OpConversionPattern;
LogicalResult
matchAndRewrite(ToCoordinatesBufferOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
// Replace the requested coordinates access with corresponding field.
// The cast_op is inserted by type converter to intermix 1:N type
// conversion.
auto desc = getDescriptorFromTensorTuple(adaptor.getTensor());
rewriter.replaceOp(op, desc.getAOSMemRef());
return success();
}
};
/// Sparse codegen rule for value accesses.
class SparseToValuesConverter : public OpConversionPattern<ToValuesOp> {
public:
using OpAdaptor = typename ToValuesOp::Adaptor;
using OpConversionPattern<ToValuesOp>::OpConversionPattern;
LogicalResult
matchAndRewrite(ToValuesOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
// Replace the requested values access with corresponding field.
// The cast_op is inserted by type converter to intermix 1:N type
// conversion.
auto desc = getDescriptorFromTensorTuple(adaptor.getTensor());
rewriter.replaceOp(op, desc.getValMemRef());
return success();
}
};
/// Sparse codegen rule for the convert operator.
class SparseConvertConverter : public OpConversionPattern<ConvertOp> {
public:
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(ConvertOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
SparseTensorEncodingAttr encDst = getSparseTensorEncoding(op.getType());
SparseTensorEncodingAttr encSrc =
getSparseTensorEncoding(op.getSource().getType());
// Different encoding (except for different bitwidth) should be handled by
// rewriting.
if (encDst.withoutBitWidths() != encSrc.withoutBitWidths()) {
return failure();
}
Type retElemTp = op.getResult().getType().getElementType();
Type srcElemTp = op.getSource().getType().getElementType();
// Fold the trivial cases.
if (retElemTp == srcElemTp && encDst == encSrc) {
rewriter.replaceOp(op, adaptor.getSource());
return success();
}
//
// Do element-wise type conversion without using InsertOp.
//
// for each memref in srcTensor:
// dst = memref.alloc
// if srcMemRefType != dstMemRefType:
// for every dst[i] = cast(src[i])
// else:
// dst = memref.copy(src)
Location loc = op.getLoc();
auto srcDesc = getDescriptorFromTensorTuple(adaptor.getSource());
SmallVector<Value> fields;
foreachFieldAndTypeInSparseTensor(
SparseTensorType(op.getResult().getType().cast<RankedTensorType>()),
[&rewriter, &fields, srcDesc,
loc](Type fTp, FieldIndex fIdx, SparseTensorFieldKind fKind, Level lvl,
DimLevelType /*dlt*/) -> bool {
// Simply reuses the storage specifier as it is an SSA value.
if (fKind == SparseTensorFieldKind::StorageSpec) {
fields.push_back(srcDesc.getSpecifier());
} else {
// Allocates new memrefs
Value srcMem = srcDesc.getMemRefField(fIdx);
// TODO: We can instead use the actual memSize in specifier, that
// would require a subViewOp to avoid overflow when copying
// values.
Value sz = linalg::createOrFoldDimOp(rewriter, loc, srcMem, 0);
auto dstMem = rewriter.create<memref::AllocOp>(
loc, fTp.cast<MemRefType>(), sz);
if (fTp != srcMem.getType()) {
// Converts elements type.
scf::buildLoopNest(
rewriter, loc, constantIndex(rewriter, loc, 0), sz,
constantIndex(rewriter, loc, 1),
[srcMem, &dstMem](OpBuilder &builder, Location loc,
ValueRange ivs) {
Value v = builder.create<memref::LoadOp>(loc, srcMem, ivs);
Value casted = genCast(builder, loc, v,
dstMem.getType().getElementType());
builder.create<memref::StoreOp>(loc, casted, dstMem, ivs);
});
} else {
// TODO: We can even reuse the same memref for the new tensor,
// but that requires a `ref-counting` based memory management
// for shared memrefs between multiple sparse tensors.
rewriter.create<memref::CopyOp>(loc, srcMem, dstMem);
}
fields.push_back(dstMem);
}
return true;
});
rewriter.replaceOp(
op, genTuple(rewriter, loc, op.getResult().getType(), fields));
return success();
}
};
class SparseExtractSliceCoverter
: public OpConversionPattern<tensor::ExtractSliceOp> {
public:
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(tensor::ExtractSliceOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
auto srcEnc = getSparseTensorEncoding(op.getSourceType());
auto dstEnc = getSparseTensorEncoding(op.getResult().getType());
if (!srcEnc && !dstEnc)
return failure();
// TODO: We should check these in ExtractSliceOp::verify.
assert(srcEnc && dstEnc && dstEnc.isSlice());
assert(srcEnc.getDimLevelType() == dstEnc.getDimLevelType());
assert(srcEnc.getDimOrdering() == dstEnc.getDimOrdering());
assert(srcEnc.getHigherOrdering() == dstEnc.getHigherOrdering());
assert(srcEnc.getPosWidth() == dstEnc.getPosWidth());
assert(srcEnc.getCrdWidth() == dstEnc.getCrdWidth());
// TODO: support dynamic slices.
for (int i = 0, e = op.getSourceType().getRank(); i < e; i++) {
assert(op.getStaticStrides()[i] == dstEnc.getStaticDimSliceStride(i));
assert(op.getStaticOffsets()[i] == dstEnc.getStaticDimSliceOffset(i));
assert(op.getStaticSizes()[i] == dstEnc.getStaticDimSliceSize(i));
}
// TODO: create a new specifer for slices (need to encode slice metadata).
// It does not matter now because only constant offset/stride are allowed.
rewriter.replaceOp(op, adaptor.getSource());
return success();
}
};
/// Sparse codegen rule for number of entries operator.
class SparseNumberOfEntriesConverter
: public OpConversionPattern<NumberOfEntriesOp> {
public:
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(NumberOfEntriesOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
// Query memSizes for the actually stored values.
rewriter.replaceOp(
op, genValMemSize(rewriter, op.getLoc(), adaptor.getTensor()));
return success();
}
};
struct SparsePackOpConverter : public OpConversionPattern<PackOp> {
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(PackOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
const auto rtp = getRankedTensorType(op.getResult());
assert(isUniqueCOOType(rtp));
SmallVector<Value> fields;
Location loc = op.getLoc();
foreachFieldAndTypeInSparseTensor(
rtp,
[&rewriter, &fields, &op, rtp,
loc](Type fType, FieldIndex fIdx, SparseTensorFieldKind fKind,
Level /*lvl*/, DimLevelType /*dlt*/) -> bool {
assert(fields.size() == fIdx);
auto enc = getSparseTensorEncoding(rtp);
Value field;
switch (fKind) {
case SparseTensorFieldKind::StorageSpec:
field = SparseTensorSpecifier::getInitValue(rewriter, loc, rtp);
break;
case SparseTensorFieldKind::PosMemRef: {
// TACO-style COO starts with a PosBuffer
// By creating a constant value for it, we avoid the complexity of
// memory management.
const auto posTp = enc.getPosType();
auto tensorType = RankedTensorType::get({2}, posTp);
auto memrefType = MemRefType::get(tensorType.getShape(),
tensorType.getElementType());
auto cstPtr = rewriter.create<arith::ConstantOp>(
loc, tensorType,
DenseElementsAttr::get(
tensorType,
ArrayRef<Attribute>{
IntegerAttr::get(posTp, 0),
IntegerAttr::get(
posTp, op.getValues().getType().getShape()[0])}));
field = rewriter.create<bufferization::ToMemrefOp>(loc, memrefType,
cstPtr);
break;
}
case SparseTensorFieldKind::CrdMemRef: {
auto tensorType = op.getCoordinates().getType();
auto memrefType = MemRefType::get(tensorType.getShape(),
tensorType.getElementType());
auto crdMemRef = rewriter.create<bufferization::ToMemrefOp>(
op->getLoc(), memrefType, op.getCoordinates());
ReassociationIndices reassociation;
for (int i = 0, e = tensorType.getRank(); i < e; i++)
reassociation.push_back(i);
// Flattened the indices buffer to rank 1.
field = rewriter.create<memref::CollapseShapeOp>(
loc, crdMemRef, ArrayRef<ReassociationIndices>(reassociation));
break;
}
case SparseTensorFieldKind::ValMemRef: {
auto tensorType = op.getValues().getType();
auto memrefType = MemRefType::get(tensorType.getShape(),
tensorType.getElementType());
field = rewriter.create<bufferization::ToMemrefOp>(
op->getLoc(), memrefType, op.getValues());
break;
}
}
assert(field);
if (fType != field.getType())
field = rewriter.create<memref::CastOp>(loc, fType, field);
fields.push_back(field);
// Returns true to continue the iteration.
return true;
});
MutSparseTensorDescriptor desc(rtp, fields);
auto noe = linalg::createOrFoldDimOp(rewriter, loc, op.getValues(), 0);
// FIXME: should use `SparseTensorType::getLvlRank` in lieu of
// `RankedTensorType::getRank`, because the latter introduces dim/lvl
// ambiguity.
for (Level lvl = 0, lvlRank = rtp.getRank(); lvl < lvlRank; lvl++) {
const auto sh = rtp.getShape()[lvl];
assert(!ShapedType::isDynamic(sh));
desc.setLvlSize(rewriter, loc, lvl, constantIndex(rewriter, loc, sh));
if (lvl == 0)
desc.setPosMemSize(rewriter, loc, lvl, constantIndex(rewriter, loc, 2));
desc.setCrdMemSize(rewriter, loc, lvl, noe);
}
desc.setValMemSize(rewriter, loc, noe);
rewriter.replaceOp(op, genTuple(rewriter, loc, desc));
return success();
}
};
struct SparseUnpackOpConverter : public OpConversionPattern<UnpackOp> {
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(UnpackOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
auto desc = getDescriptorFromTensorTuple(adaptor.getTensor());
Location loc = op.getLoc();
const auto srcTp = getSparseTensorType(op.getTensor());
const Level lvlRank = srcTp.getLvlRank();
assert(isUniqueCOOType(srcTp) && desc.getFields().size() == 4);
Value flatBuf = lvlRank == 1 ? desc.getCrdMemRefOrView(rewriter, loc, 0)
: desc.getAOSMemRef();
Value valuesBuf = desc.getValMemRef();
// If frontend requests a static buffer, we reallocate the
// values/coordinates to ensure that we meet their need.
const auto valuesTp = getRankedTensorType(op.getValues());
if (valuesTp.hasStaticShape()) {
valuesBuf =
reallocOrSubView(rewriter, loc, valuesTp.getShape()[0], valuesBuf);
}
const auto coordinatesTp = getRankedTensorType(op.getCoordinates());
if (coordinatesTp.hasStaticShape()) {
auto len = coordinatesTp.getShape()[0] * coordinatesTp.getShape()[1];
flatBuf = reallocOrSubView(rewriter, loc, len, flatBuf);
}
Value coordinatesBuf = rewriter.create<memref::ExpandShapeOp>(
loc,
MemRefType::get(coordinatesTp.getShape(),
coordinatesTp.getElementType()),
flatBuf, ArrayRef{ReassociationIndices{0, 1}});
// Converts MemRefs back to Tensors.
Value values = rewriter.create<bufferization::ToTensorOp>(loc, valuesBuf);
Value coordinates =
rewriter.create<bufferization::ToTensorOp>(loc, coordinatesBuf);
Value nse = genCast(rewriter, loc, desc.getValMemSize(rewriter, loc),
op.getNse().getType());
rewriter.replaceOp(op, {values, coordinates, nse});
return success();
}
};
struct SparseNewOpConverter : public OpConversionPattern<NewOp> {
using OpConversionPattern::OpConversionPattern;
LogicalResult
matchAndRewrite(NewOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
Location loc = op.getLoc();
const auto dstTp = getSparseTensorType(op.getResult());
// Creating COO with NewOp is handled by direct IR codegen. All other cases
// are handled by rewriting.
if (!dstTp.hasEncoding() || getCOOStart(dstTp.getEncoding()) != 0)
return failure();
// Implement the NewOp(filename) as follows:
// %reader = @getSparseTensorReader(%filename)
// %nse = @getSparseTensorNSE(%reader)
// %coo = bufferization.alloc_tensor an ordered COO with
// dst dim ordering, size_hint = %nse
// %coordinates = sparse_tensor.coordinates_buffer(%coo)
// %values = sparse_tensor.values(%coo)
// %isSorted = @sparseTensorReaderReadToBuffers(%coordinates, %values)
// if (! %isSorted) sparse_tensor.sort_coo(%nse, %coordinates, %values)
// update storage specifier
// @delSparseTensorReader(%reader)
// Create a sparse tensor reader.
const Value fileName = op.getSource();
const Type opaqueTp = getOpaquePointerType(rewriter);
// FIXME: use `createCheckedSparseTensorReader` instead, because
// `createSparseTensorReader` is unsafe.
Value reader = createFuncCall(rewriter, loc, "createSparseTensorReader",
{opaqueTp}, {fileName}, EmitCInterface::Off)
.getResult(0);
const Type indexTp = rewriter.getIndexType();
const Dimension dimRank = dstTp.getDimRank();
const Level lvlRank = dstTp.getLvlRank();
// If the result tensor has dynamic dimensions, get the dynamic sizes from
// the sparse tensor reader.
SmallVector<Value> dynSizes;
if (dstTp.hasDynamicDimShape()) {
// FIXME: call `getSparseTensorReaderDimSizes` instead, because
// `copySparseTensorReaderDimSizes` copies the memref over,
// instead of just accessing the reader's memory directly.
Value dimSizes = genAlloca(rewriter, loc, dimRank, indexTp);
createFuncCall(rewriter, loc, "copySparseTensorReaderDimSizes", {},
{reader, dimSizes}, EmitCInterface::On)
.getResult(0);
for (const auto &d : llvm::enumerate(dstTp.getDimShape()))
if (ShapedType::isDynamic(d.value()))
dynSizes.push_back(rewriter.create<memref::LoadOp>(
loc, dimSizes, constantIndex(rewriter, loc, d.index())));
}
Value nse = createFuncCall(rewriter, loc, "getSparseTensorReaderNSE",
{indexTp}, {reader}, EmitCInterface::Off)
.getResult(0);
// Construct allocation for each field.
SmallVector<Value> fields;
createAllocFields(rewriter, loc, dstTp, dynSizes, /*enableInit=*/false,
fields, nse);
MutSparseTensorDescriptor desc(dstTp, fields);
// Construct the `dim2lvl` buffer for handing off to the runtime library.
// FIXME: This code is (mostly) copied from the SparseTensorConversion.cpp
// handling of `NewOp`, and only handles permutations. Fixing this
// requires waiting for wrengr to finish redoing the CL that handles
// all dim<->lvl stuff more robustly.
SmallVector<Value> dim2lvlValues(dimRank);
if (!dstTp.isIdentity()) {
const auto dimOrder = dstTp.getDimToLvlMap();
assert(dimOrder.isPermutation() && "Got non-permutation");
for (Level l = 0; l < lvlRank; l++) {
const Dimension d = dimOrder.getDimPosition(l);
dim2lvlValues[d] = constantIndex(rewriter, loc, l);
}
} else {
// The `SparseTensorType` ctor already ensures `dimRank == lvlRank`
// when `isIdentity`; so no need to re-assert it here.
for (Dimension d = 0; d < dimRank; d++)
dim2lvlValues[d] = constantIndex(rewriter, loc, d);
}
Value dim2lvl = allocaBuffer(rewriter, loc, dim2lvlValues);
// Read the COO tensor data.
Value xs = desc.getAOSMemRef();
Value ys = desc.getValMemRef();
const Type boolTp = rewriter.getIntegerType(1);
const Type elemTp = dstTp.getElementType();
const Type crdTp = dstTp.getCrdType();
// FIXME: This function name is weird; should rename to
// "sparseTensorReaderReadToBuffers".
SmallString<32> readToBuffersFuncName{"getSparseTensorReaderRead",
overheadTypeFunctionSuffix(crdTp),
primaryTypeFunctionSuffix(elemTp)};
Value isSorted =
createFuncCall(rewriter, loc, readToBuffersFuncName, {boolTp},
{reader, dim2lvl, xs, ys}, EmitCInterface::On)
.getResult(0);
// If the destination tensor is a sorted COO, we need to sort the COO tensor
// data if the input elements aren't sorted yet.
if (dstTp.isOrderedLvl(lvlRank - 1)) {
Value kFalse = constantI1(rewriter, loc, false);
Value notSorted = rewriter.create<arith::CmpIOp>(
loc, arith::CmpIPredicate::eq, isSorted, kFalse);
scf::IfOp ifOp =
rewriter.create<scf::IfOp>(loc, notSorted, /*else*/ false);
rewriter.setInsertionPointToStart(&ifOp.getThenRegion().front());
rewriter.create<SortCooOp>(
loc, nse, xs, ValueRange{ys}, rewriter.getIndexAttr(lvlRank),
rewriter.getIndexAttr(0), SparseTensorSortKind::HybridQuickSort);
rewriter.setInsertionPointAfter(ifOp);
}
// Set PosMemRef0[1] = nse.
const Value c1 = constantIndex(rewriter, loc, 1);
const Value posMemref0 = desc.getPosMemRef(0);
const Type posTp = dstTp.getPosType();
const Value posNse = genCast(rewriter, loc, nse, posTp);
rewriter.create<memref::StoreOp>(loc, posNse, posMemref0, c1);
// Update storage specifier.
Value coordinatesSize = rewriter.create<arith::MulIOp>(
loc, nse, constantIndex(rewriter, loc, lvlRank));
desc.setSpecifierField(rewriter, loc, StorageSpecifierKind::CrdMemSize, 0,
coordinatesSize);
desc.setSpecifierField(rewriter, loc, StorageSpecifierKind::ValMemSize,
std::nullopt, nse);
// Release the sparse tensor reader.
createFuncCall(rewriter, loc, "delSparseTensorReader", {}, {reader},
EmitCInterface::Off);
// Replace operation with resulting memrefs.
rewriter.replaceOp(op, genTuple(rewriter, loc, dstTp, fields));
return success();
}
};
} // namespace
//===----------------------------------------------------------------------===//
// Public method for populating conversion rules.
//===----------------------------------------------------------------------===//
/// Populates the given patterns list with conversion rules required for
/// the sparsification of linear algebra operations.
void mlir::populateSparseTensorCodegenPatterns(
TypeConverter &typeConverter, RewritePatternSet &patterns,
bool enableBufferInitialization) {
patterns.add<SparsePackOpConverter, SparseUnpackOpConverter,
SparseReturnConverter, SparseCallConverter, SparseDimOpConverter,
SparseCastConverter, SparseTensorDeallocConverter,
SparseExtractSliceCoverter, SparseTensorLoadConverter,
SparseExpandConverter, SparseCompressConverter,
SparseInsertConverter, SparseToPositionsConverter,
SparseToCoordinatesConverter, SparseToCoordinatesBufferConverter,
SparseToValuesConverter, SparseConvertConverter,
SparseNewOpConverter, SparseNumberOfEntriesConverter>(
typeConverter, patterns.getContext());
patterns.add<SparseTensorAllocConverter>(typeConverter, patterns.getContext(),
enableBufferInitialization);
}