523 lines
20 KiB
C++
523 lines
20 KiB
C++
//===- ShardingInterface.cpp -------------------------------------*- C++-*-===//
|
|
//
|
|
// 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 "mlir/Dialect/Mesh/Interfaces/ShardingInterface.h"
|
|
#include "mlir/Dialect/Mesh/IR/MeshOps.h"
|
|
#include "mlir/Dialect/Utils/IndexingUtils.h"
|
|
#include "mlir/IR/AffineMap.h"
|
|
#include "mlir/Support/LLVM.h"
|
|
#include "llvm/ADT/SmallSet.h"
|
|
#include "llvm/Support/Debug.h"
|
|
|
|
#include <algorithm>
|
|
#include <utility>
|
|
|
|
#define DEBUG_TYPE "sharding-interface"
|
|
#define DBGS() (llvm::dbgs() << "[" DEBUG_TYPE << "]: ")
|
|
|
|
using namespace mlir;
|
|
using namespace mlir::mesh;
|
|
|
|
#include "mlir/Dialect/Mesh/Interfaces/ShardingInterface.cpp.inc"
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// common util functions
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
static LogicalResult
|
|
checkOperandAffineExprRecursively(AffineExpr expr,
|
|
SmallVectorImpl<bool> &seenIds) {
|
|
switch (expr.getKind()) {
|
|
case AffineExprKind::Add: {
|
|
auto binOpExpr = cast<AffineBinaryOpExpr>(expr);
|
|
AffineExpr lhs = binOpExpr.getLHS();
|
|
AffineExpr rhs = binOpExpr.getRHS();
|
|
if (failed(checkOperandAffineExprRecursively(lhs, seenIds)))
|
|
return failure();
|
|
if (failed(checkOperandAffineExprRecursively(rhs, seenIds)))
|
|
return failure();
|
|
return success();
|
|
}
|
|
case AffineExprKind::Mul: {
|
|
auto binOpExpr = cast<AffineBinaryOpExpr>(expr);
|
|
AffineExpr lhs = binOpExpr.getLHS();
|
|
AffineExpr rhs = binOpExpr.getRHS();
|
|
AffineExpr dimExpr;
|
|
if (lhs.getKind() == AffineExprKind::DimId &&
|
|
rhs.getKind() == AffineExprKind::Constant) {
|
|
dimExpr = lhs;
|
|
} else if (rhs.getKind() == AffineExprKind::DimId &&
|
|
lhs.getKind() == AffineExprKind::Constant) {
|
|
dimExpr = rhs;
|
|
} else
|
|
return failure();
|
|
unsigned position = cast<AffineDimExpr>(dimExpr).getPosition();
|
|
if ((size_t)position >= seenIds.size() || seenIds[position])
|
|
return failure();
|
|
seenIds[position] = true;
|
|
return success();
|
|
}
|
|
case AffineExprKind::DimId: {
|
|
unsigned position = cast<AffineDimExpr>(expr).getPosition();
|
|
if ((size_t)position >= seenIds.size() || seenIds[position])
|
|
return failure();
|
|
seenIds[position] = true;
|
|
return success();
|
|
}
|
|
default:
|
|
return failure();
|
|
}
|
|
}
|
|
|
|
static FailureOr<llvm::SmallSet<unsigned, 2>>
|
|
checkOperandAffineExpr(AffineExpr expr, unsigned numDims) {
|
|
SmallVector<bool> seenIds(numDims, false);
|
|
if (failed(checkOperandAffineExprRecursively(expr, seenIds)))
|
|
return failure();
|
|
|
|
llvm::SmallSet<unsigned, 2> positions;
|
|
for (auto it : llvm::enumerate(seenIds)) {
|
|
if (it.value())
|
|
positions.insert((unsigned)it.index());
|
|
}
|
|
return positions;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// mesh::getMeshShardingAttr
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
FailureOr<std::pair<bool, MeshShardingAttr>>
|
|
mesh::getMeshShardingAttr(OpResult result) {
|
|
Value val = result.cast<Value>();
|
|
bool anyShardedForDef = llvm::any_of(val.getUsers(), [](Operation *user) {
|
|
auto shardOp = llvm::dyn_cast<mesh::ShardOp>(user);
|
|
if (!shardOp)
|
|
return false;
|
|
return !shardOp.getAnnotateForUsers();
|
|
});
|
|
|
|
if (anyShardedForDef) {
|
|
// expected to have exact one use if it has a use of `mesh.shard` without
|
|
// unit attr annotate_for_users
|
|
if (!val.hasOneUse())
|
|
return failure();
|
|
auto shardOp = llvm::cast<mesh::ShardOp>(*val.getUsers().begin());
|
|
return std::make_pair(false, shardOp.getShard());
|
|
}
|
|
|
|
bool anyShardedForUsers = llvm::any_of(val.getUsers(), [](Operation *user) {
|
|
auto shardOp = llvm::dyn_cast<mesh::ShardOp>(user);
|
|
if (!shardOp)
|
|
return false;
|
|
return shardOp.getAnnotateForUsers();
|
|
});
|
|
if (anyShardedForUsers) {
|
|
SmallVector<ShardOp> shardOps;
|
|
for (Operation *user : val.getUsers()) {
|
|
ShardOp shardOp = llvm::dyn_cast<ShardOp>(user);
|
|
if (shardOp)
|
|
shardOps.push_back(shardOp);
|
|
}
|
|
MeshShardingAttr shardForDef = shardOps[0].getShard();
|
|
for (size_t i = 1; i < shardOps.size(); ++i) {
|
|
// TODO: Deduce a reasonable mesh sharding attr for def when they are
|
|
// different
|
|
assert(shardOps[i].getShard() == shardForDef &&
|
|
"only support all shard ops have the same mesh sharding attr");
|
|
}
|
|
return std::make_pair(true, shardForDef);
|
|
}
|
|
return failure();
|
|
}
|
|
|
|
FailureOr<std::pair<bool, MeshShardingAttr>>
|
|
mesh::getMeshShardingAttr(OpOperand &opOperand) {
|
|
Value val = opOperand.get();
|
|
if (ShardOp shardOp = val.getDefiningOp<ShardOp>())
|
|
return std::make_pair(shardOp.getAnnotateForUsers(), shardOp.getShard());
|
|
|
|
return failure();
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// ShardingInterface::verifyShardingInterfaceImpl
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
LogicalResult mesh::ShardingInterface::verifyShardingInterfaceImpl() {
|
|
Operation *op = getOperation();
|
|
|
|
// check operands and results type
|
|
for (Type type : op->getOperandTypes())
|
|
if (!llvm::isa<RankedTensorType>(type))
|
|
return failure();
|
|
for (Type type : op->getResultTypes())
|
|
if (!llvm::isa<RankedTensorType>(type))
|
|
return failure();
|
|
|
|
// check loop types
|
|
SmallVector<IteratorType> loopTypes = getLoopIteratorTypes();
|
|
if (loopTypes.size() == 0)
|
|
return failure();
|
|
|
|
// check maps
|
|
SmallVector<AffineMap> maps = getIndexingMaps();
|
|
if (maps.size() == 0)
|
|
return failure();
|
|
unsigned numOperands = op->getNumOperands();
|
|
unsigned numResults = op->getNumResults();
|
|
if (numOperands + numResults != maps.size())
|
|
return failure();
|
|
|
|
for (OpResult result : op->getResults()) {
|
|
auto resultType = result.getType().dyn_cast<RankedTensorType>();
|
|
if (!resultType)
|
|
return failure();
|
|
AffineMap map = maps[numOperands + result.getResultNumber()];
|
|
if (!map.isProjectedPermutation()) {
|
|
return failure();
|
|
}
|
|
}
|
|
|
|
return success();
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// ShardingInterface::printLoopTypesAndIndexingMaps
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void mesh::ShardingInterface::printLoopTypesAndIndexingMaps(raw_ostream &os) {
|
|
os << "print loop types and indexing maps for: \n";
|
|
getOperation()->print(os);
|
|
os << "\n";
|
|
os << "loop types: [";
|
|
for (IteratorType type : getLoopIteratorTypes()) {
|
|
os << stringifyEnum(type) << " ";
|
|
}
|
|
os << "]\n";
|
|
os << "indexing maps: \n";
|
|
for (AffineMap map : getIndexingMaps())
|
|
os << map << "\n";
|
|
os << "\n";
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// detail::defaultGetShardingOption
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace {
|
|
|
|
// Update the given `shardingOption` according to `meshAxes` and `loopIdx`
|
|
static LogicalResult fillShardingOption(Operation *op,
|
|
ShardingOption &shardingOption,
|
|
FlatSymbolRefAttr cluster,
|
|
ArrayRef<MeshAxis> meshAxes,
|
|
unsigned loopIdx) {
|
|
if ((shardingOption.cluster && cluster &&
|
|
shardingOption.cluster != cluster) ||
|
|
(!shardingOption.shardingArray[loopIdx].empty() &&
|
|
shardingOption.shardingArray[loopIdx] != meshAxes)) {
|
|
LLVM_DEBUG(DBGS() << "sharding option conflicts on loop iterator "
|
|
<< loopIdx << "\n");
|
|
return failure();
|
|
}
|
|
for (size_t i = 0; i < shardingOption.shardingArray.size(); ++i) {
|
|
if (i == loopIdx)
|
|
continue;
|
|
|
|
for (MeshAxis axis : meshAxes) {
|
|
if (llvm::is_contained(shardingOption.shardingArray[i], axis)) {
|
|
LLVM_DEBUG(DBGS() << "sharding option conflicts because mesh axes "
|
|
<< axis << " duplicate");
|
|
return failure();
|
|
}
|
|
}
|
|
}
|
|
if (cluster)
|
|
shardingOption.cluster = cluster;
|
|
if (shardingOption.shardingArray[loopIdx].empty())
|
|
shardingOption.shardingArray[loopIdx].append(meshAxes.begin(),
|
|
meshAxes.end());
|
|
return success();
|
|
}
|
|
|
|
} // namespace
|
|
|
|
FailureOr<ShardingOption> mesh::detail::defaultGetShardingOption(
|
|
Operation *op, ArrayRef<MeshShardingAttr> operandShardings,
|
|
ArrayRef<MeshShardingAttr> resultShardings) {
|
|
ShardingInterface shardingOp = llvm::cast<ShardingInterface>(op);
|
|
ShardingOption shardingOption;
|
|
|
|
if (failed(shardingOp.verifyShardingInterfaceImpl()))
|
|
return op->emitOpError() << "invalid sharding interface implementation";
|
|
SmallVector<IteratorType> loopTypes = shardingOp.getLoopIteratorTypes();
|
|
SmallVector<AffineMap> maps = shardingOp.getIndexingMaps();
|
|
unsigned numOperands = op->getNumOperands();
|
|
shardingOption.shardingArray.resize(loopTypes.size());
|
|
llvm::SmallVector<MeshAxis> partialMeshAxes;
|
|
Partial partialType;
|
|
llvm::SmallSet<unsigned, 4> visitedLoopIndices;
|
|
bool anyShardingInResultsOrOperands = false;
|
|
|
|
// 1. Fill sharding option based on op results
|
|
for (auto shardingIt : llvm::enumerate(resultShardings)) {
|
|
MeshShardingAttr shardAttr = shardingIt.value();
|
|
if (!shardAttr)
|
|
continue;
|
|
AffineMap map = maps[numOperands + shardingIt.index()];
|
|
anyShardingInResultsOrOperands = true;
|
|
// Handle the split axes: calculate the corresponding loop index for each
|
|
// split axes sub-array, and then store the sub-array to
|
|
// shardingOption[index]
|
|
for (auto it : llvm::zip(map.getResults(), shardAttr.getSplitAxes())) {
|
|
AffineExpr expr = std::get<0>(it);
|
|
ArrayRef<MeshAxis> axes = std::get<1>(it).asArrayRef();
|
|
auto dim = cast<AffineDimExpr>(expr);
|
|
unsigned index = dim.getPosition();
|
|
visitedLoopIndices.insert(index);
|
|
if (failed(fillShardingOption(op, shardingOption, shardAttr.getCluster(),
|
|
axes, index)))
|
|
return failure();
|
|
}
|
|
|
|
// Handle the partial axes: at this stage, the exact loop index/indices
|
|
// cannot be decided because there could be multiple reduction loops.
|
|
ArrayRef<MeshAxis> partialAxes = shardAttr.getPartialAxes();
|
|
if (!partialAxes.empty()) {
|
|
if (!partialMeshAxes.empty())
|
|
return op->emitOpError() << "at most one result with partial axes is "
|
|
"supported at present";
|
|
partialType = shardAttr.getPartialType();
|
|
partialMeshAxes.append(partialAxes.begin(), partialAxes.end());
|
|
// Add all the reduction loop indices to `visitedLoopIndices` if
|
|
// `partialAxes` is not empty
|
|
for (size_t loopIdx = 0; loopIdx < loopTypes.size(); ++loopIdx) {
|
|
if (isReductionLoop(loopTypes[loopIdx]))
|
|
visitedLoopIndices.insert(loopIdx);
|
|
}
|
|
}
|
|
}
|
|
|
|
// 2. Fill sharding option based on operands
|
|
for (auto shardingIt : llvm::enumerate(operandShardings)) {
|
|
MeshShardingAttr shardAttr = shardingIt.value();
|
|
if (!shardAttr)
|
|
continue;
|
|
|
|
anyShardingInResultsOrOperands = true;
|
|
AffineMap map = maps[shardingIt.index()];
|
|
unsigned numDims = map.getNumDims();
|
|
|
|
// Handle the split axes. Partial axes don't need to be handled because they
|
|
// only affect the defining op of the operand.
|
|
//
|
|
// TODO: Change to process the operands with single loop index first and
|
|
// then the operands with multiple loop indices.
|
|
for (auto it : llvm::zip(map.getResults(), shardAttr.getSplitAxes())) {
|
|
AffineExpr expr = std::get<0>(it);
|
|
ArrayRef<MeshAxis> axes = std::get<1>(it).asArrayRef();
|
|
FailureOr<llvm::SmallSet<unsigned, 2>> loopIndices =
|
|
checkOperandAffineExpr(expr, numDims);
|
|
if (failed(loopIndices))
|
|
return op->emitOpError()
|
|
<< "operand's affine expression is restricted to const_i * "
|
|
"dim_i + const_j + dim_j + ...";
|
|
if (loopIndices->empty())
|
|
continue;
|
|
if (loopIndices->size() == 1) {
|
|
unsigned loopIdx = *loopIndices->begin();
|
|
visitedLoopIndices.insert(loopIdx);
|
|
if (failed(fillShardingOption(op, shardingOption,
|
|
shardAttr.getCluster(), axes, loopIdx)))
|
|
return failure();
|
|
}
|
|
// If multiple loop indices correspond to a dimension of an operand, it is
|
|
// difficult to infer which loop indices are responsible for sharding.
|
|
// Therefore, the exact loop index must be specified by others.
|
|
if (loopIndices->size() > 1) {
|
|
bool seenLoopIndices = false;
|
|
for (unsigned loopIdx : *loopIndices) {
|
|
if (visitedLoopIndices.contains(loopIdx)) {
|
|
seenLoopIndices = true;
|
|
break;
|
|
}
|
|
}
|
|
if (!seenLoopIndices)
|
|
return op->emitOpError()
|
|
<< "the operand " << shardingIt.index()
|
|
<< " has multiple loop indices in a dimension, but none of "
|
|
"them could be found in the exactly specified annotation "
|
|
"of op results or operands.";
|
|
}
|
|
}
|
|
}
|
|
|
|
// 3. Finalize sharding option
|
|
if (!partialMeshAxes.empty()) {
|
|
bool anyNonEmptyReductionLoop = llvm::any_of(
|
|
llvm::enumerate(shardingOption.shardingArray), [&](auto it) {
|
|
SmallVector<MeshAxis> &subArray = it.value();
|
|
int64_t idx = it.index();
|
|
return isReductionLoop(loopTypes[idx]) && !subArray.empty();
|
|
});
|
|
if (!anyNonEmptyReductionLoop) {
|
|
bool filled = false;
|
|
for (size_t idx = 0; idx < loopTypes.size(); ++idx) {
|
|
if (isReductionLoop(loopTypes[idx]) &&
|
|
areReductionAndPartialMatch(loopTypes[idx], partialType)) {
|
|
std::ignore = fillShardingOption(op, shardingOption, nullptr,
|
|
partialMeshAxes, idx);
|
|
filled = true;
|
|
break;
|
|
}
|
|
}
|
|
if (!filled)
|
|
return op->emitOpError() << "no matched reduction loop found for the "
|
|
"result's partial type";
|
|
}
|
|
}
|
|
removeTrailingEmptySubArray(shardingOption.shardingArray);
|
|
if (!anyShardingInResultsOrOperands)
|
|
shardingOption.empty = true;
|
|
return shardingOption;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// detail::defaultAddShardingAnnotations
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace {
|
|
|
|
// To add a `mesh.shard` op for the given result, based on the details provided
|
|
// in `shardingOption`, `map`, and `loopTypes`.
|
|
static LogicalResult addShardOp(OpBuilder &b, OpResult result,
|
|
const ShardingOption &shardingOption,
|
|
AffineMap map,
|
|
ArrayRef<IteratorType> loopTypes) {
|
|
FailureOr<std::pair<bool, MeshShardingAttr>> maybeSharding =
|
|
getMeshShardingAttr(result);
|
|
if (succeeded(maybeSharding) && !maybeSharding->first)
|
|
return success();
|
|
|
|
auto resultType = result.getType().cast<RankedTensorType>();
|
|
SmallVector<SmallVector<MeshAxis>> splitAxes(resultType.getRank());
|
|
SmallVector<MeshAxis> partialAxes;
|
|
|
|
// process the split axes
|
|
for (auto it : llvm::enumerate(map.getResults())) {
|
|
AffineExpr expr = it.value();
|
|
// `expr` must be an `AffineDimExpr` because `map` is verified by
|
|
// isProjectedPermutation
|
|
auto dim = cast<AffineDimExpr>(expr);
|
|
unsigned loopIdx = dim.getPosition();
|
|
if (loopIdx < shardingOption.shardingArray.size())
|
|
splitAxes[it.index()].append(shardingOption.shardingArray[loopIdx]);
|
|
}
|
|
|
|
// process the partial axes
|
|
// partialType will be ignored if partialAxes is empty
|
|
Partial partialType = Partial::Sum;
|
|
for (auto it : llvm::zip(loopTypes, shardingOption.shardingArray)) {
|
|
IteratorType iType = std::get<0>(it);
|
|
if (isReductionLoop(iType)) {
|
|
Partial curPartialType = getPartialTypeFromReduction(iType);
|
|
if (!partialAxes.empty())
|
|
assert(partialType == curPartialType &&
|
|
"Only one reduction type is supported");
|
|
partialType = curPartialType;
|
|
const SmallVector<MeshAxis> &axis = std::get<1>(it);
|
|
partialAxes.append(axis);
|
|
}
|
|
}
|
|
|
|
removeTrailingEmptySubArray(splitAxes);
|
|
MeshShardingAttr shardAttr =
|
|
MeshShardingAttr::get(b.getContext(), shardingOption.cluster, splitAxes,
|
|
partialAxes, partialType);
|
|
OpBuilder::InsertionGuard guard(b);
|
|
b.setInsertionPointAfterValue(result);
|
|
auto shardOp = b.create<ShardOp>(result.getLoc(), resultType, result,
|
|
shardAttr, /*annotate_for_users*/ false);
|
|
result.replaceAllUsesExcept(shardOp, shardOp);
|
|
return success();
|
|
}
|
|
|
|
// To add a `mesh.shard` op for the given operand, based on the details provided
|
|
// in `shardingOption`, `map`, and `loopTypes`.
|
|
static LogicalResult addShardOp(OpBuilder &b, OpOperand &opOperand,
|
|
const ShardingOption &shardingOption,
|
|
AffineMap map,
|
|
ArrayRef<IteratorType> loopTypes) {
|
|
auto maybeShardingAttr = getMeshShardingAttr(opOperand);
|
|
if (succeeded(maybeShardingAttr) && maybeShardingAttr->first)
|
|
return success();
|
|
Value operand = opOperand.get();
|
|
auto operandType = operand.getType().cast<RankedTensorType>();
|
|
SmallVector<SmallVector<MeshAxis>> splitAxes(operandType.getRank());
|
|
unsigned numDims = map.getNumDims();
|
|
for (auto it : llvm::enumerate(map.getResults())) {
|
|
int64_t idx = it.index();
|
|
AffineExpr expr = it.value();
|
|
FailureOr<llvm::SmallSet<unsigned, 2>> loopIndices =
|
|
checkOperandAffineExpr(expr, numDims);
|
|
if (failed(loopIndices))
|
|
return failure();
|
|
SmallVector<unsigned> shardedLoopIndices;
|
|
for (unsigned loopIdx : *loopIndices) {
|
|
if ((size_t)loopIdx < shardingOption.shardingArray.size() &&
|
|
!shardingOption.shardingArray[loopIdx].empty())
|
|
shardedLoopIndices.push_back(loopIdx);
|
|
}
|
|
// mostly one sharded loop index is accepted
|
|
if (shardedLoopIndices.size() > 1)
|
|
return failure();
|
|
if (shardedLoopIndices.size() == 1) {
|
|
splitAxes[idx].append(
|
|
shardingOption.shardingArray[shardedLoopIndices[0]]);
|
|
}
|
|
}
|
|
|
|
removeTrailingEmptySubArray(splitAxes);
|
|
MeshShardingAttr shardAttr =
|
|
MeshShardingAttr::get(b.getContext(), shardingOption.cluster, splitAxes);
|
|
OpBuilder::InsertionGuard guard(b);
|
|
b.setInsertionPoint(opOperand.getOwner());
|
|
auto shardOp = b.create<ShardOp>(operand.getLoc(), operandType, operand,
|
|
shardAttr, true);
|
|
opOperand.set(shardOp);
|
|
|
|
return success();
|
|
}
|
|
|
|
} // namespace
|
|
|
|
LogicalResult mesh::detail::defaultAddShardingAnnotations(
|
|
Operation *op, OpBuilder &b, const ShardingOption &shardingOption) {
|
|
ShardingInterface shardingOp = llvm::cast<ShardingInterface>(op);
|
|
SmallVector<IteratorType> loopTypes = shardingOp.getLoopIteratorTypes();
|
|
SmallVector<AffineMap> maps = shardingOp.getIndexingMaps();
|
|
unsigned numOperands = op->getNumOperands();
|
|
|
|
// 1. add mesh.shard ops for all op results
|
|
for (OpResult result : op->getResults()) {
|
|
if (failed(addShardOp(b, result, shardingOption,
|
|
maps[numOperands + result.getResultNumber()],
|
|
loopTypes)))
|
|
return failure();
|
|
}
|
|
|
|
// 2. add mesh.shard ops for all operands
|
|
for (OpOperand &opOperand : op->getOpOperands()) {
|
|
if (failed(addShardOp(b, opOperand, shardingOption,
|
|
maps[opOperand.getOperandNumber()], loopTypes)))
|
|
return failure();
|
|
}
|
|
|
|
return success();
|
|
}
|