Files
clang-p2996/mlir/lib/IR/Builders.cpp
Matthias Springer 2d3bbb6aaf [mlir][Transforms] Dialect conversion: Erase materialized constants instead of rollback (#136489)
When illegal (and not legalizable) constant operations are materialized
during a dialect conversion as part of op folding, these operations must
be deleted again. This used to be implemented via the rollback
mechanism. This commit switches the implementation to regular rewriter
API usage: simply delete the materialized constants with `eraseOp`.

This commit is in preparation of the One-Shot Dialect Conversion
refactoring, which will disallow IR rollbacks.

This commit also adds a new optional parameter to `OpBuilder::tryFold`
to get hold of the materialized constant ops.
2025-04-22 09:12:00 +02:00

605 lines
20 KiB
C++

//===- Builders.cpp - Helpers for constructing MLIR Classes ---------------===//
//
// 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/IR/Builders.h"
#include "mlir/IR/AffineExpr.h"
#include "mlir/IR/AffineMap.h"
#include "mlir/IR/BuiltinTypes.h"
#include "mlir/IR/Dialect.h"
#include "mlir/IR/IRMapping.h"
#include "mlir/IR/IntegerSet.h"
#include "mlir/IR/Matchers.h"
#include "mlir/IR/SymbolTable.h"
#include "llvm/ADT/SmallVectorExtras.h"
#include "llvm/Support/raw_ostream.h"
using namespace mlir;
//===----------------------------------------------------------------------===//
// Locations.
//===----------------------------------------------------------------------===//
Location Builder::getUnknownLoc() { return UnknownLoc::get(context); }
Location Builder::getFusedLoc(ArrayRef<Location> locs, Attribute metadata) {
return FusedLoc::get(locs, metadata, context);
}
//===----------------------------------------------------------------------===//
// Types.
//===----------------------------------------------------------------------===//
FloatType Builder::getBF16Type() { return BFloat16Type::get(context); }
FloatType Builder::getF16Type() { return Float16Type::get(context); }
FloatType Builder::getTF32Type() { return FloatTF32Type::get(context); }
FloatType Builder::getF32Type() { return Float32Type::get(context); }
FloatType Builder::getF64Type() { return Float64Type::get(context); }
FloatType Builder::getF80Type() { return Float80Type::get(context); }
FloatType Builder::getF128Type() { return Float128Type::get(context); }
IndexType Builder::getIndexType() { return IndexType::get(context); }
IntegerType Builder::getI1Type() { return IntegerType::get(context, 1); }
IntegerType Builder::getI2Type() { return IntegerType::get(context, 2); }
IntegerType Builder::getI4Type() { return IntegerType::get(context, 4); }
IntegerType Builder::getI8Type() { return IntegerType::get(context, 8); }
IntegerType Builder::getI16Type() { return IntegerType::get(context, 16); }
IntegerType Builder::getI32Type() { return IntegerType::get(context, 32); }
IntegerType Builder::getI64Type() { return IntegerType::get(context, 64); }
IntegerType Builder::getIntegerType(unsigned width) {
return IntegerType::get(context, width);
}
IntegerType Builder::getIntegerType(unsigned width, bool isSigned) {
return IntegerType::get(
context, width, isSigned ? IntegerType::Signed : IntegerType::Unsigned);
}
FunctionType Builder::getFunctionType(TypeRange inputs, TypeRange results) {
return FunctionType::get(context, inputs, results);
}
TupleType Builder::getTupleType(TypeRange elementTypes) {
return TupleType::get(context, elementTypes);
}
NoneType Builder::getNoneType() { return NoneType::get(context); }
//===----------------------------------------------------------------------===//
// Attributes.
//===----------------------------------------------------------------------===//
NamedAttribute Builder::getNamedAttr(StringRef name, Attribute val) {
return NamedAttribute(name, val);
}
UnitAttr Builder::getUnitAttr() { return UnitAttr::get(context); }
BoolAttr Builder::getBoolAttr(bool value) {
return BoolAttr::get(context, value);
}
DictionaryAttr Builder::getDictionaryAttr(ArrayRef<NamedAttribute> value) {
return DictionaryAttr::get(context, value);
}
IntegerAttr Builder::getIndexAttr(int64_t value) {
return IntegerAttr::get(getIndexType(), APInt(64, value));
}
IntegerAttr Builder::getI64IntegerAttr(int64_t value) {
return IntegerAttr::get(getIntegerType(64), APInt(64, value));
}
DenseIntElementsAttr Builder::getBoolVectorAttr(ArrayRef<bool> values) {
return DenseIntElementsAttr::get(
VectorType::get(static_cast<int64_t>(values.size()), getI1Type()),
values);
}
DenseIntElementsAttr Builder::getI32VectorAttr(ArrayRef<int32_t> values) {
return DenseIntElementsAttr::get(
VectorType::get(static_cast<int64_t>(values.size()), getIntegerType(32)),
values);
}
DenseIntElementsAttr Builder::getI64VectorAttr(ArrayRef<int64_t> values) {
return DenseIntElementsAttr::get(
VectorType::get(static_cast<int64_t>(values.size()), getIntegerType(64)),
values);
}
DenseIntElementsAttr Builder::getIndexVectorAttr(ArrayRef<int64_t> values) {
return DenseIntElementsAttr::get(
VectorType::get(static_cast<int64_t>(values.size()), getIndexType()),
values);
}
DenseFPElementsAttr Builder::getF32VectorAttr(ArrayRef<float> values) {
return DenseFPElementsAttr::get(
VectorType::get(static_cast<float>(values.size()), getF32Type()), values);
}
DenseFPElementsAttr Builder::getF64VectorAttr(ArrayRef<double> values) {
return DenseFPElementsAttr::get(
VectorType::get(static_cast<double>(values.size()), getF64Type()),
values);
}
DenseBoolArrayAttr Builder::getDenseBoolArrayAttr(ArrayRef<bool> values) {
return DenseBoolArrayAttr::get(context, values);
}
DenseI8ArrayAttr Builder::getDenseI8ArrayAttr(ArrayRef<int8_t> values) {
return DenseI8ArrayAttr::get(context, values);
}
DenseI16ArrayAttr Builder::getDenseI16ArrayAttr(ArrayRef<int16_t> values) {
return DenseI16ArrayAttr::get(context, values);
}
DenseI32ArrayAttr Builder::getDenseI32ArrayAttr(ArrayRef<int32_t> values) {
return DenseI32ArrayAttr::get(context, values);
}
DenseI64ArrayAttr Builder::getDenseI64ArrayAttr(ArrayRef<int64_t> values) {
return DenseI64ArrayAttr::get(context, values);
}
DenseF32ArrayAttr Builder::getDenseF32ArrayAttr(ArrayRef<float> values) {
return DenseF32ArrayAttr::get(context, values);
}
DenseF64ArrayAttr Builder::getDenseF64ArrayAttr(ArrayRef<double> values) {
return DenseF64ArrayAttr::get(context, values);
}
DenseIntElementsAttr Builder::getI32TensorAttr(ArrayRef<int32_t> values) {
return DenseIntElementsAttr::get(
RankedTensorType::get(static_cast<int64_t>(values.size()),
getIntegerType(32)),
values);
}
DenseIntElementsAttr Builder::getI64TensorAttr(ArrayRef<int64_t> values) {
return DenseIntElementsAttr::get(
RankedTensorType::get(static_cast<int64_t>(values.size()),
getIntegerType(64)),
values);
}
DenseIntElementsAttr Builder::getIndexTensorAttr(ArrayRef<int64_t> values) {
return DenseIntElementsAttr::get(
RankedTensorType::get(static_cast<int64_t>(values.size()),
getIndexType()),
values);
}
IntegerAttr Builder::getI32IntegerAttr(int32_t value) {
// The APInt always uses isSigned=true here because we accept the value
// as int32_t.
return IntegerAttr::get(getIntegerType(32),
APInt(32, value, /*isSigned=*/true));
}
IntegerAttr Builder::getSI32IntegerAttr(int32_t value) {
return IntegerAttr::get(getIntegerType(32, /*isSigned=*/true),
APInt(32, value, /*isSigned=*/true));
}
IntegerAttr Builder::getUI32IntegerAttr(uint32_t value) {
return IntegerAttr::get(getIntegerType(32, /*isSigned=*/false),
APInt(32, (uint64_t)value, /*isSigned=*/false));
}
IntegerAttr Builder::getI16IntegerAttr(int16_t value) {
return IntegerAttr::get(getIntegerType(16), APInt(16, value));
}
IntegerAttr Builder::getI8IntegerAttr(int8_t value) {
// The APInt always uses isSigned=true here because we accept the value
// as int8_t.
return IntegerAttr::get(getIntegerType(8),
APInt(8, value, /*isSigned=*/true));
}
IntegerAttr Builder::getIntegerAttr(Type type, int64_t value) {
if (type.isIndex())
return IntegerAttr::get(type, APInt(64, value));
// TODO: Avoid implicit trunc?
// See https://github.com/llvm/llvm-project/issues/112510.
return IntegerAttr::get(type, APInt(type.getIntOrFloatBitWidth(), value,
type.isSignedInteger(),
/*implicitTrunc=*/true));
}
IntegerAttr Builder::getIntegerAttr(Type type, const APInt &value) {
return IntegerAttr::get(type, value);
}
FloatAttr Builder::getF64FloatAttr(double value) {
return FloatAttr::get(getF64Type(), APFloat(value));
}
FloatAttr Builder::getF32FloatAttr(float value) {
return FloatAttr::get(getF32Type(), APFloat(value));
}
FloatAttr Builder::getF16FloatAttr(float value) {
return FloatAttr::get(getF16Type(), value);
}
FloatAttr Builder::getFloatAttr(Type type, double value) {
return FloatAttr::get(type, value);
}
FloatAttr Builder::getFloatAttr(Type type, const APFloat &value) {
return FloatAttr::get(type, value);
}
StringAttr Builder::getStringAttr(const Twine &bytes) {
return StringAttr::get(context, bytes);
}
ArrayAttr Builder::getArrayAttr(ArrayRef<Attribute> value) {
return ArrayAttr::get(context, value);
}
ArrayAttr Builder::getBoolArrayAttr(ArrayRef<bool> values) {
auto attrs = llvm::map_to_vector<8>(
values, [this](bool v) -> Attribute { return getBoolAttr(v); });
return getArrayAttr(attrs);
}
ArrayAttr Builder::getI32ArrayAttr(ArrayRef<int32_t> values) {
auto attrs = llvm::map_to_vector<8>(
values, [this](int32_t v) -> Attribute { return getI32IntegerAttr(v); });
return getArrayAttr(attrs);
}
ArrayAttr Builder::getI64ArrayAttr(ArrayRef<int64_t> values) {
auto attrs = llvm::map_to_vector<8>(
values, [this](int64_t v) -> Attribute { return getI64IntegerAttr(v); });
return getArrayAttr(attrs);
}
ArrayAttr Builder::getIndexArrayAttr(ArrayRef<int64_t> values) {
auto attrs = llvm::map_to_vector<8>(values, [this](int64_t v) -> Attribute {
return getIntegerAttr(IndexType::get(getContext()), v);
});
return getArrayAttr(attrs);
}
ArrayAttr Builder::getF32ArrayAttr(ArrayRef<float> values) {
auto attrs = llvm::map_to_vector<8>(
values, [this](float v) -> Attribute { return getF32FloatAttr(v); });
return getArrayAttr(attrs);
}
ArrayAttr Builder::getF64ArrayAttr(ArrayRef<double> values) {
auto attrs = llvm::map_to_vector<8>(
values, [this](double v) -> Attribute { return getF64FloatAttr(v); });
return getArrayAttr(attrs);
}
ArrayAttr Builder::getStrArrayAttr(ArrayRef<StringRef> values) {
auto attrs = llvm::map_to_vector<8>(
values, [this](StringRef v) -> Attribute { return getStringAttr(v); });
return getArrayAttr(attrs);
}
ArrayAttr Builder::getTypeArrayAttr(TypeRange values) {
auto attrs = llvm::map_to_vector<8>(
values, [](Type v) -> Attribute { return TypeAttr::get(v); });
return getArrayAttr(attrs);
}
ArrayAttr Builder::getAffineMapArrayAttr(ArrayRef<AffineMap> values) {
auto attrs = llvm::map_to_vector<8>(
values, [](AffineMap v) -> Attribute { return AffineMapAttr::get(v); });
return getArrayAttr(attrs);
}
TypedAttr Builder::getZeroAttr(Type type) {
if (llvm::isa<FloatType>(type))
return getFloatAttr(type, 0.0);
if (llvm::isa<IndexType>(type))
return getIndexAttr(0);
if (llvm::dyn_cast<IntegerType>(type))
return getIntegerAttr(type,
APInt(llvm::cast<IntegerType>(type).getWidth(), 0));
if (llvm::isa<RankedTensorType, VectorType>(type)) {
auto vtType = llvm::cast<ShapedType>(type);
auto element = getZeroAttr(vtType.getElementType());
if (!element)
return {};
return DenseElementsAttr::get(vtType, element);
}
return {};
}
TypedAttr Builder::getOneAttr(Type type) {
if (llvm::isa<FloatType>(type))
return getFloatAttr(type, 1.0);
if (llvm::isa<IndexType>(type))
return getIndexAttr(1);
if (llvm::dyn_cast<IntegerType>(type))
return getIntegerAttr(type,
APInt(llvm::cast<IntegerType>(type).getWidth(), 1));
if (llvm::isa<RankedTensorType, VectorType>(type)) {
auto vtType = llvm::cast<ShapedType>(type);
auto element = getOneAttr(vtType.getElementType());
if (!element)
return {};
return DenseElementsAttr::get(vtType, element);
}
return {};
}
//===----------------------------------------------------------------------===//
// Affine Expressions, Affine Maps, and Integer Sets.
//===----------------------------------------------------------------------===//
AffineExpr Builder::getAffineDimExpr(unsigned position) {
return mlir::getAffineDimExpr(position, context);
}
AffineExpr Builder::getAffineSymbolExpr(unsigned position) {
return mlir::getAffineSymbolExpr(position, context);
}
AffineExpr Builder::getAffineConstantExpr(int64_t constant) {
return mlir::getAffineConstantExpr(constant, context);
}
AffineMap Builder::getEmptyAffineMap() { return AffineMap::get(context); }
AffineMap Builder::getConstantAffineMap(int64_t val) {
return AffineMap::get(/*dimCount=*/0, /*symbolCount=*/0,
getAffineConstantExpr(val));
}
AffineMap Builder::getDimIdentityMap() {
return AffineMap::get(/*dimCount=*/1, /*symbolCount=*/0, getAffineDimExpr(0));
}
AffineMap Builder::getMultiDimIdentityMap(unsigned rank) {
SmallVector<AffineExpr, 4> dimExprs;
dimExprs.reserve(rank);
for (unsigned i = 0; i < rank; ++i)
dimExprs.push_back(getAffineDimExpr(i));
return AffineMap::get(/*dimCount=*/rank, /*symbolCount=*/0, dimExprs,
context);
}
AffineMap Builder::getSymbolIdentityMap() {
return AffineMap::get(/*dimCount=*/0, /*symbolCount=*/1,
getAffineSymbolExpr(0));
}
AffineMap Builder::getSingleDimShiftAffineMap(int64_t shift) {
// expr = d0 + shift.
auto expr = getAffineDimExpr(0) + shift;
return AffineMap::get(/*dimCount=*/1, /*symbolCount=*/0, expr);
}
AffineMap Builder::getShiftedAffineMap(AffineMap map, int64_t shift) {
SmallVector<AffineExpr, 4> shiftedResults;
shiftedResults.reserve(map.getNumResults());
for (auto resultExpr : map.getResults())
shiftedResults.push_back(resultExpr + shift);
return AffineMap::get(map.getNumDims(), map.getNumSymbols(), shiftedResults,
context);
}
//===----------------------------------------------------------------------===//
// OpBuilder
//===----------------------------------------------------------------------===//
/// Insert the given operation at the current insertion point and return it.
Operation *OpBuilder::insert(Operation *op) {
if (block) {
block->getOperations().insert(insertPoint, op);
if (listener)
listener->notifyOperationInserted(op, /*previous=*/{});
}
return op;
}
Block *OpBuilder::createBlock(Region *parent, Region::iterator insertPt,
TypeRange argTypes, ArrayRef<Location> locs) {
assert(parent && "expected valid parent region");
assert(argTypes.size() == locs.size() && "argument location mismatch");
if (insertPt == Region::iterator())
insertPt = parent->end();
Block *b = new Block();
b->addArguments(argTypes, locs);
parent->getBlocks().insert(insertPt, b);
setInsertionPointToEnd(b);
if (listener)
listener->notifyBlockInserted(b, /*previous=*/nullptr, /*previousIt=*/{});
return b;
}
/// Add new block with 'argTypes' arguments and set the insertion point to the
/// end of it. The block is placed before 'insertBefore'.
Block *OpBuilder::createBlock(Block *insertBefore, TypeRange argTypes,
ArrayRef<Location> locs) {
assert(insertBefore && "expected valid insertion block");
return createBlock(insertBefore->getParent(), Region::iterator(insertBefore),
argTypes, locs);
}
/// Create an operation given the fields represented as an OperationState.
Operation *OpBuilder::create(const OperationState &state) {
return insert(Operation::create(state));
}
/// Creates an operation with the given fields.
Operation *OpBuilder::create(Location loc, StringAttr opName,
ValueRange operands, TypeRange types,
ArrayRef<NamedAttribute> attributes,
BlockRange successors,
MutableArrayRef<std::unique_ptr<Region>> regions) {
OperationState state(loc, opName, operands, types, attributes, successors,
regions);
return create(state);
}
LogicalResult
OpBuilder::tryFold(Operation *op, SmallVectorImpl<Value> &results,
SmallVectorImpl<Operation *> *materializedConstants) {
assert(results.empty() && "expected empty results");
ResultRange opResults = op->getResults();
results.reserve(opResults.size());
auto cleanupFailure = [&] {
results.clear();
return failure();
};
// If this operation is already a constant, there is nothing to do.
if (matchPattern(op, m_Constant()))
return cleanupFailure();
// Try to fold the operation.
SmallVector<OpFoldResult, 4> foldResults;
if (failed(op->fold(foldResults)))
return cleanupFailure();
// An in-place fold does not require generation of any constants.
if (foldResults.empty())
return success();
// A temporary builder used for creating constants during folding.
OpBuilder cstBuilder(context);
SmallVector<Operation *, 1> generatedConstants;
// Populate the results with the folded results.
Dialect *dialect = op->getDialect();
for (auto [foldResult, expectedType] :
llvm::zip_equal(foldResults, opResults.getTypes())) {
// Normal values get pushed back directly.
if (auto value = llvm::dyn_cast_if_present<Value>(foldResult)) {
results.push_back(value);
continue;
}
// Otherwise, try to materialize a constant operation.
if (!dialect)
return cleanupFailure();
// Ask the dialect to materialize a constant operation for this value.
Attribute attr = cast<Attribute>(foldResult);
auto *constOp = dialect->materializeConstant(cstBuilder, attr, expectedType,
op->getLoc());
if (!constOp) {
// Erase any generated constants.
for (Operation *cst : generatedConstants)
cst->erase();
return cleanupFailure();
}
assert(matchPattern(constOp, m_Constant()));
generatedConstants.push_back(constOp);
results.push_back(constOp->getResult(0));
}
// If we were successful, insert any generated constants.
for (Operation *cst : generatedConstants)
insert(cst);
// Return materialized constant operations.
if (materializedConstants)
*materializedConstants = std::move(generatedConstants);
return success();
}
/// Helper function that sends block insertion notifications for every block
/// that is directly nested in the given op.
static void notifyBlockInsertions(Operation *op,
OpBuilder::Listener *listener) {
for (Region &r : op->getRegions())
for (Block &b : r.getBlocks())
listener->notifyBlockInserted(&b, /*previous=*/nullptr,
/*previousIt=*/{});
}
Operation *OpBuilder::clone(Operation &op, IRMapping &mapper) {
Operation *newOp = op.clone(mapper);
newOp = insert(newOp);
// The `insert` call above handles the notification for inserting `newOp`
// itself. But if `newOp` has any regions, we need to notify the listener
// about any ops that got inserted inside those regions as part of cloning.
if (listener) {
// The `insert` call above notifies about op insertion, but not about block
// insertion.
notifyBlockInsertions(newOp, listener);
auto walkFn = [&](Operation *walkedOp) {
listener->notifyOperationInserted(walkedOp, /*previous=*/{});
notifyBlockInsertions(walkedOp, listener);
};
for (Region &region : newOp->getRegions())
region.walk<WalkOrder::PreOrder>(walkFn);
}
return newOp;
}
Operation *OpBuilder::clone(Operation &op) {
IRMapping mapper;
return clone(op, mapper);
}
void OpBuilder::cloneRegionBefore(Region &region, Region &parent,
Region::iterator before, IRMapping &mapping) {
region.cloneInto(&parent, before, mapping);
// Fast path: If no listener is attached, there is no more work to do.
if (!listener)
return;
// Notify about op/block insertion.
for (auto it = mapping.lookup(&region.front())->getIterator(); it != before;
++it) {
listener->notifyBlockInserted(&*it, /*previous=*/nullptr,
/*previousIt=*/{});
it->walk<WalkOrder::PreOrder>([&](Operation *walkedOp) {
listener->notifyOperationInserted(walkedOp, /*previous=*/{});
notifyBlockInsertions(walkedOp, listener);
});
}
}
void OpBuilder::cloneRegionBefore(Region &region, Region &parent,
Region::iterator before) {
IRMapping mapping;
cloneRegionBefore(region, parent, before, mapping);
}
void OpBuilder::cloneRegionBefore(Region &region, Block *before) {
cloneRegionBefore(region, *before->getParent(), before->getIterator());
}