|
| 1 | +//===-- OneToNTypeConversion.h - Utils for 1:N type conversion --*- C++ -*-===// |
| 2 | +// |
| 3 | +// Licensed under the Apache License v2.0 with LLVM Exceptions. |
| 4 | +// See https://llvm.org/LICENSE.txt for license information. |
| 5 | +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 6 | +// |
| 7 | +//===----------------------------------------------------------------------===// |
| 8 | +// |
| 9 | +// Note: The 1:N dialect conversion is deprecated and will be removed soon. |
| 10 | +// 1:N support has been added to the regular dialect conversion driver. |
| 11 | +// |
| 12 | +// This file provides utils for implementing (poor-man's) dialect conversion |
| 13 | +// passes with 1:N type conversions. |
| 14 | +// |
| 15 | +// The main function, `applyPartialOneToNConversion`, first applies a set of |
| 16 | +// `RewritePattern`s, which produce unrealized casts to convert the operands and |
| 17 | +// results from and to the source types, and then replaces all newly added |
| 18 | +// unrealized casts by user-provided materializations. For this to work, the |
| 19 | +// main function requires a special `TypeConverter`, a special |
| 20 | +// `PatternRewriter`, and special RewritePattern`s, which extend their |
| 21 | +// respective base classes for 1:N type converions. |
| 22 | +// |
| 23 | +// Note that this is much more simple-minded than the "real" dialect conversion, |
| 24 | +// which checks for legality before applying patterns and does probably many |
| 25 | +// other additional things. Ideally, some of the extensions here could be |
| 26 | +// integrated there. |
| 27 | +// |
| 28 | +//===----------------------------------------------------------------------===// |
| 29 | + |
| 30 | +#ifndef MLIR_TRANSFORMS_ONETONTYPECONVERSION_H |
| 31 | +#define MLIR_TRANSFORMS_ONETONTYPECONVERSION_H |
| 32 | + |
| 33 | +#include "mlir/IR/PatternMatch.h" |
| 34 | +#include "mlir/Transforms/DialectConversion.h" |
| 35 | +#include "llvm/ADT/SmallVector.h" |
| 36 | + |
| 37 | +namespace mlir { |
| 38 | + |
| 39 | +/// Stores a 1:N mapping of types and provides several useful accessors. This |
| 40 | +/// class extends `SignatureConversion`, which already supports 1:N type |
| 41 | +/// mappings but lacks some accessors into the mapping as well as access to the |
| 42 | +/// original types. |
| 43 | +class OneToNTypeMapping : public TypeConverter::SignatureConversion { |
| 44 | +public: |
| 45 | + OneToNTypeMapping(TypeRange originalTypes) |
| 46 | + : TypeConverter::SignatureConversion(originalTypes.size()), |
| 47 | + originalTypes(originalTypes) {} |
| 48 | + |
| 49 | + using TypeConverter::SignatureConversion::getConvertedTypes; |
| 50 | + |
| 51 | + /// Returns the list of types that corresponds to the original type at the |
| 52 | + /// given index. |
| 53 | + TypeRange getConvertedTypes(unsigned originalTypeNo) const; |
| 54 | + |
| 55 | + /// Returns the list of original types. |
| 56 | + TypeRange getOriginalTypes() const { return originalTypes; } |
| 57 | + |
| 58 | + /// Returns the slice of converted values that corresponds the original value |
| 59 | + /// at the given index. |
| 60 | + ValueRange getConvertedValues(ValueRange convertedValues, |
| 61 | + unsigned originalValueNo) const; |
| 62 | + |
| 63 | + /// Fills the given result vector with as many copies of the location of the |
| 64 | + /// original value as the number of values it is converted to. |
| 65 | + void convertLocation(Value originalValue, unsigned originalValueNo, |
| 66 | + llvm::SmallVectorImpl<Location> &result) const; |
| 67 | + |
| 68 | + /// Fills the given result vector with as many copies of the lociation of each |
| 69 | + /// original value as the number of values they are respectively converted to. |
| 70 | + void convertLocations(ValueRange originalValues, |
| 71 | + llvm::SmallVectorImpl<Location> &result) const; |
| 72 | + |
| 73 | + /// Returns true iff at least one type conversion maps an input type to a type |
| 74 | + /// that is different from itself. |
| 75 | + bool hasNonIdentityConversion() const; |
| 76 | + |
| 77 | +private: |
| 78 | + llvm::SmallVector<Type> originalTypes; |
| 79 | +}; |
| 80 | + |
| 81 | +/// Extends the basic `RewritePattern` class with a type converter member and |
| 82 | +/// some accessors to it. This is useful for patterns that are not |
| 83 | +/// `ConversionPattern`s but still require access to a type converter. |
| 84 | +class RewritePatternWithConverter : public mlir::RewritePattern { |
| 85 | +public: |
| 86 | + /// Construct a conversion pattern with the given converter, and forward the |
| 87 | + /// remaining arguments to RewritePattern. |
| 88 | + template <typename... Args> |
| 89 | + RewritePatternWithConverter(const TypeConverter &typeConverter, |
| 90 | + Args &&...args) |
| 91 | + : RewritePattern(std::forward<Args>(args)...), |
| 92 | + typeConverter(&typeConverter) {} |
| 93 | + |
| 94 | + /// Return the type converter held by this pattern, or nullptr if the pattern |
| 95 | + /// does not require type conversion. |
| 96 | + const TypeConverter *getTypeConverter() const { return typeConverter; } |
| 97 | + |
| 98 | + template <typename ConverterTy> |
| 99 | + std::enable_if_t<std::is_base_of<TypeConverter, ConverterTy>::value, |
| 100 | + const ConverterTy *> |
| 101 | + getTypeConverter() const { |
| 102 | + return static_cast<const ConverterTy *>(typeConverter); |
| 103 | + } |
| 104 | + |
| 105 | +protected: |
| 106 | + /// A type converter for use by this pattern. |
| 107 | + const TypeConverter *const typeConverter; |
| 108 | +}; |
| 109 | + |
| 110 | +/// Specialization of `PatternRewriter` that `OneToNConversionPattern`s use. The |
| 111 | +/// class provides additional rewrite methods that are specific to 1:N type |
| 112 | +/// conversions. |
| 113 | +class OneToNPatternRewriter : public PatternRewriter { |
| 114 | +public: |
| 115 | + OneToNPatternRewriter(MLIRContext *context, |
| 116 | + OpBuilder::Listener *listener = nullptr) |
| 117 | + : PatternRewriter(context, listener) {} |
| 118 | + |
| 119 | + /// Replaces the results of the operation with the specified list of values |
| 120 | + /// mapped back to the original types as specified in the provided type |
| 121 | + /// mapping. That type mapping must match the replaced op (i.e., the original |
| 122 | + /// types must be the same as the result types of the op) and the new values |
| 123 | + /// (i.e., the converted types must be the same as the types of the new |
| 124 | + /// values). |
| 125 | + /// FIXME: The 1:N dialect conversion is deprecated and will be removed soon. |
| 126 | + /// Use replaceOpWithMultiple() instead. |
| 127 | + void replaceOp(Operation *op, ValueRange newValues, |
| 128 | + const OneToNTypeMapping &resultMapping); |
| 129 | + using PatternRewriter::replaceOp; |
| 130 | + |
| 131 | + /// Applies the given argument conversion to the given block. This consists of |
| 132 | + /// replacing each original argument with N arguments as specified in the |
| 133 | + /// argument conversion and inserting unrealized casts from the converted |
| 134 | + /// values to the original types, which are then used in lieu of the original |
| 135 | + /// ones. (Eventually, `applyPartialOneToNConversion` replaces these casts |
| 136 | + /// with a user-provided argument materialization if necessary.) This is |
| 137 | + /// similar to `ArgConverter::applySignatureConversion` but (1) handles 1:N |
| 138 | + /// type conversion properly and probably (2) doesn't handle many other edge |
| 139 | + /// cases. |
| 140 | + Block *applySignatureConversion(Block *block, |
| 141 | + OneToNTypeMapping &argumentConversion); |
| 142 | +}; |
| 143 | + |
| 144 | +/// Base class for patterns with 1:N type conversions. Derived classes have to |
| 145 | +/// overwrite the `matchAndRewrite` overlaod that provides additional |
| 146 | +/// information for 1:N type conversions. |
| 147 | +class OneToNConversionPattern : public RewritePatternWithConverter { |
| 148 | +public: |
| 149 | + using RewritePatternWithConverter::RewritePatternWithConverter; |
| 150 | + |
| 151 | + /// This function has to be implemented by derived classes and is called from |
| 152 | + /// the usual overloads. Like in "normal" `DialectConversion`, the function is |
| 153 | + /// provided with the converted operands (which thus have target types). Since |
| 154 | + /// 1:N conversions are supported, there is usually no 1:1 relationship |
| 155 | + /// between the original and the converted operands. Instead, the provided |
| 156 | + /// `operandMapping` can be used to access the converted operands that |
| 157 | + /// correspond to a particular original operand. Similarly, `resultMapping` |
| 158 | + /// is provided to help with assembling the result values, which may have 1:N |
| 159 | + /// correspondences as well. In that case, the original op should be replaced |
| 160 | + /// with the overload of `replaceOp` that takes the provided `resultMapping` |
| 161 | + /// in order to deal with the mapping of converted result values to their |
| 162 | + /// usages in the original types correctly. |
| 163 | + virtual LogicalResult matchAndRewrite(Operation *op, |
| 164 | + OneToNPatternRewriter &rewriter, |
| 165 | + const OneToNTypeMapping &operandMapping, |
| 166 | + const OneToNTypeMapping &resultMapping, |
| 167 | + ValueRange convertedOperands) const = 0; |
| 168 | + |
| 169 | + LogicalResult matchAndRewrite(Operation *op, |
| 170 | + PatternRewriter &rewriter) const final; |
| 171 | +}; |
| 172 | + |
| 173 | +/// This class is a wrapper around `OneToNConversionPattern` for matching |
| 174 | +/// against instances of a particular op class. |
| 175 | +template <typename SourceOp> |
| 176 | +class OneToNOpConversionPattern : public OneToNConversionPattern { |
| 177 | +public: |
| 178 | + OneToNOpConversionPattern(const TypeConverter &typeConverter, |
| 179 | + MLIRContext *context, PatternBenefit benefit = 1, |
| 180 | + ArrayRef<StringRef> generatedNames = {}) |
| 181 | + : OneToNConversionPattern(typeConverter, SourceOp::getOperationName(), |
| 182 | + benefit, context, generatedNames) {} |
| 183 | + /// Generic adaptor around the root op of this pattern using the converted |
| 184 | + /// operands. Importantly, each operand is represented as a *range* of values, |
| 185 | + /// namely the N values each original operand gets converted to. Concretely, |
| 186 | + /// this makes the result type of the accessor functions of the adaptor class |
| 187 | + /// be a `ValueRange`. |
| 188 | + class OpAdaptor |
| 189 | + : public SourceOp:: template GenericAdaptor<ArrayRef<ValueRange>> { |
| 190 | + public: |
| 191 | + using RangeT = ArrayRef<ValueRange>; |
| 192 | + using BaseT = typename SourceOp::template GenericAdaptor<RangeT>; |
| 193 | + using Properties = typename SourceOp::template InferredProperties<SourceOp>; |
| 194 | + |
| 195 | + OpAdaptor(const OneToNTypeMapping *operandMapping, |
| 196 | + const OneToNTypeMapping *resultMapping, |
| 197 | + const ValueRange *convertedOperands, RangeT values, SourceOp op) |
| 198 | + : BaseT(values, op), operandMapping(operandMapping), |
| 199 | + resultMapping(resultMapping), convertedOperands(convertedOperands) {} |
| 200 | + |
| 201 | + /// Get the type mapping of the original operands to the converted operands. |
| 202 | + const OneToNTypeMapping &getOperandMapping() const { |
| 203 | + return *operandMapping; |
| 204 | + } |
| 205 | + |
| 206 | + /// Get the type mapping of the original results to the converted results. |
| 207 | + const OneToNTypeMapping &getResultMapping() const { return *resultMapping; } |
| 208 | + |
| 209 | + /// Get a flat range of all converted operands. Unlike `getOperands`, which |
| 210 | + /// returns an `ArrayRef` with one `ValueRange` for each original operand, |
| 211 | + /// this function returns a `ValueRange` that contains all converted |
| 212 | + /// operands irrespectively of which operand they originated from. |
| 213 | + ValueRange getFlatOperands() const { return *convertedOperands; } |
| 214 | + |
| 215 | + private: |
| 216 | + const OneToNTypeMapping *operandMapping; |
| 217 | + const OneToNTypeMapping *resultMapping; |
| 218 | + const ValueRange *convertedOperands; |
| 219 | + }; |
| 220 | + |
| 221 | + using OneToNConversionPattern::matchAndRewrite; |
| 222 | + |
| 223 | + /// Overload that derived classes have to override for their op type. |
| 224 | + virtual LogicalResult |
| 225 | + matchAndRewrite(SourceOp op, OpAdaptor adaptor, |
| 226 | + OneToNPatternRewriter &rewriter) const = 0; |
| 227 | + |
| 228 | + LogicalResult matchAndRewrite(Operation *op, OneToNPatternRewriter &rewriter, |
| 229 | + const OneToNTypeMapping &operandMapping, |
| 230 | + const OneToNTypeMapping &resultMapping, |
| 231 | + ValueRange convertedOperands) const final { |
| 232 | + // Wrap converted operands and type mappings into an adaptor. |
| 233 | + SmallVector<ValueRange> valueRanges; |
| 234 | + for (int64_t i = 0; i < op->getNumOperands(); i++) { |
| 235 | + auto values = operandMapping.getConvertedValues(convertedOperands, i); |
| 236 | + valueRanges.push_back(values); |
| 237 | + } |
| 238 | + OpAdaptor adaptor(&operandMapping, &resultMapping, &convertedOperands, |
| 239 | + valueRanges, cast<SourceOp>(op)); |
| 240 | + |
| 241 | + // Call overload implemented by the derived class. |
| 242 | + return matchAndRewrite(cast<SourceOp>(op), adaptor, rewriter); |
| 243 | + } |
| 244 | +}; |
| 245 | + |
| 246 | +/// Applies the given set of patterns recursively on the given op and adds user |
| 247 | +/// materializations where necessary. The patterns are expected to be |
| 248 | +/// `OneToNConversionPattern`, which help converting the types of the operands |
| 249 | +/// and results of the matched ops. The provided type converter is used to |
| 250 | +/// convert the operands of matched ops from their original types to operands |
| 251 | +/// with different types. Unlike in `DialectConversion`, this supports 1:N type |
| 252 | +/// conversions. Those conversions at the "boundary" of the pattern application, |
| 253 | +/// where converted results are not consumed by replaced ops that expect the |
| 254 | +/// converted operands or vice versa, the function inserts user materializations |
| 255 | +/// from the type converter. Also unlike `DialectConversion`, there are no legal |
| 256 | +/// or illegal types; the function simply applies the given patterns and does |
| 257 | +/// not fail if some ops or types remain unconverted (i.e., the conversion is |
| 258 | +/// only "partial"). |
| 259 | +/// FIXME: The 1:N dialect conversion is deprecated and will be removed soon. |
| 260 | +/// 1:N support has been added to the regular dialect conversion driver. |
| 261 | +/// Use applyPartialConversion() instead. |
| 262 | +LogicalResult |
| 263 | +applyPartialOneToNConversion(Operation *op, TypeConverter &typeConverter, |
| 264 | + const FrozenRewritePatternSet &patterns); |
| 265 | + |
| 266 | +/// Add a pattern to the given pattern list to convert the signature of a |
| 267 | +/// FunctionOpInterface op with the given type converter. This only supports |
| 268 | +/// ops which use FunctionType to represent their type. This is intended to be |
| 269 | +/// used with the 1:N dialect conversion. |
| 270 | +/// FIXME: The 1:N dialect conversion is deprecated and will be removed soon. |
| 271 | +/// 1:N support has been added to the regular dialect conversion driver. |
| 272 | +/// Use populateFunctionOpInterfaceTypeConversionPattern() instead. |
| 273 | +void populateOneToNFunctionOpInterfaceTypeConversionPattern( |
| 274 | + StringRef functionLikeOpName, const TypeConverter &converter, |
| 275 | + RewritePatternSet &patterns); |
| 276 | +template <typename FuncOpT> |
| 277 | +void populateOneToNFunctionOpInterfaceTypeConversionPattern( |
| 278 | + const TypeConverter &converter, RewritePatternSet &patterns) { |
| 279 | + populateOneToNFunctionOpInterfaceTypeConversionPattern( |
| 280 | + FuncOpT::getOperationName(), converter, patterns); |
| 281 | +} |
| 282 | + |
| 283 | +} // namespace mlir |
| 284 | + |
| 285 | +#endif // MLIR_TRANSFORMS_ONETONTYPECONVERSION_H |
0 commit comments