171 lines · cpp
1//===- FuncToEmitC.cpp - Func to EmitC Patterns -----------------*- C++ -*-===//2//3// Part of the LLVM Project, 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-exception6//7//===----------------------------------------------------------------------===//8//9// This file implements patterns to convert the Func dialect to the EmitC10// dialect.11//12//===----------------------------------------------------------------------===//13 14#include "mlir/Conversion/FuncToEmitC/FuncToEmitC.h"15 16#include "mlir/Conversion/ConvertToEmitC/ToEmitCInterface.h"17#include "mlir/Dialect/EmitC/IR/EmitC.h"18#include "mlir/Dialect/Func/IR/FuncOps.h"19#include "mlir/Transforms/DialectConversion.h"20 21using namespace mlir;22 23namespace {24 25/// Implement the interface to convert Func to EmitC.26struct FuncToEmitCDialectInterface : public ConvertToEmitCPatternInterface {27 using ConvertToEmitCPatternInterface::ConvertToEmitCPatternInterface;28 29 /// Hook for derived dialect interface to provide conversion patterns30 /// and mark dialect legal for the conversion target.31 void populateConvertToEmitCConversionPatterns(32 ConversionTarget &target, TypeConverter &typeConverter,33 RewritePatternSet &patterns) const final {34 populateFuncToEmitCPatterns(typeConverter, patterns);35 }36};37} // namespace38 39void mlir::registerConvertFuncToEmitCInterface(DialectRegistry ®istry) {40 registry.addExtension(+[](MLIRContext *ctx, func::FuncDialect *dialect) {41 dialect->addInterfaces<FuncToEmitCDialectInterface>();42 });43}44 45//===----------------------------------------------------------------------===//46// Conversion Patterns47//===----------------------------------------------------------------------===//48 49namespace {50class CallOpConversion final : public OpConversionPattern<func::CallOp> {51public:52 using OpConversionPattern<func::CallOp>::OpConversionPattern;53 54 LogicalResult55 matchAndRewrite(func::CallOp callOp, OpAdaptor adaptor,56 ConversionPatternRewriter &rewriter) const override {57 // Multiple results func cannot be converted to `emitc.func`.58 if (callOp.getNumResults() > 1)59 return rewriter.notifyMatchFailure(60 callOp, "only functions with zero or one result can be converted");61 62 rewriter.replaceOpWithNewOp<emitc::CallOp>(callOp, callOp.getResultTypes(),63 adaptor.getOperands(),64 callOp->getAttrs());65 66 return success();67 }68};69 70class FuncOpConversion final : public OpConversionPattern<func::FuncOp> {71public:72 using OpConversionPattern<func::FuncOp>::OpConversionPattern;73 74 LogicalResult75 matchAndRewrite(func::FuncOp funcOp, OpAdaptor adaptor,76 ConversionPatternRewriter &rewriter) const override {77 FunctionType fnType = funcOp.getFunctionType();78 79 if (fnType.getNumResults() > 1)80 return rewriter.notifyMatchFailure(81 funcOp, "only functions with zero or one result can be converted");82 83 TypeConverter::SignatureConversion signatureConverter(84 fnType.getNumInputs());85 for (const auto &argType : enumerate(fnType.getInputs())) {86 auto convertedType = getTypeConverter()->convertType(argType.value());87 if (!convertedType)88 return rewriter.notifyMatchFailure(funcOp,89 "argument type conversion failed");90 signatureConverter.addInputs(argType.index(), convertedType);91 }92 93 Type resultType;94 if (fnType.getNumResults() == 1) {95 resultType = getTypeConverter()->convertType(fnType.getResult(0));96 if (!resultType)97 return rewriter.notifyMatchFailure(funcOp,98 "result type conversion failed");99 }100 101 // Create the converted `emitc.func` op.102 emitc::FuncOp newFuncOp = emitc::FuncOp::create(103 rewriter, funcOp.getLoc(), funcOp.getName(),104 FunctionType::get(rewriter.getContext(),105 signatureConverter.getConvertedTypes(),106 resultType ? TypeRange(resultType) : TypeRange()));107 108 // Copy over all attributes other than the function name and type.109 for (const auto &namedAttr : funcOp->getAttrs()) {110 if (namedAttr.getName() != funcOp.getFunctionTypeAttrName() &&111 namedAttr.getName() != SymbolTable::getSymbolAttrName())112 newFuncOp->setAttr(namedAttr.getName(), namedAttr.getValue());113 }114 115 // Add `extern` to specifiers if `func.func` is declaration only.116 if (funcOp.isDeclaration()) {117 ArrayAttr specifiers = rewriter.getStrArrayAttr({"extern"});118 newFuncOp.setSpecifiersAttr(specifiers);119 }120 121 // Add `static` to specifiers if `func.func` is private but not a122 // declaration.123 if (funcOp.isPrivate() && !funcOp.isDeclaration()) {124 ArrayAttr specifiers = rewriter.getStrArrayAttr({"static"});125 newFuncOp.setSpecifiersAttr(specifiers);126 }127 128 if (!funcOp.isDeclaration()) {129 rewriter.inlineRegionBefore(funcOp.getBody(), newFuncOp.getBody(),130 newFuncOp.end());131 if (failed(rewriter.convertRegionTypes(132 &newFuncOp.getBody(), *getTypeConverter(), &signatureConverter)))133 return failure();134 }135 rewriter.eraseOp(funcOp);136 137 return success();138 }139};140 141class ReturnOpConversion final : public OpConversionPattern<func::ReturnOp> {142public:143 using OpConversionPattern<func::ReturnOp>::OpConversionPattern;144 145 LogicalResult146 matchAndRewrite(func::ReturnOp returnOp, OpAdaptor adaptor,147 ConversionPatternRewriter &rewriter) const override {148 if (returnOp.getNumOperands() > 1)149 return rewriter.notifyMatchFailure(150 returnOp, "only zero or one operand is supported");151 152 rewriter.replaceOpWithNewOp<emitc::ReturnOp>(153 returnOp,154 returnOp.getNumOperands() ? adaptor.getOperands()[0] : nullptr);155 return success();156 }157};158} // namespace159 160//===----------------------------------------------------------------------===//161// Pattern population162//===----------------------------------------------------------------------===//163 164void mlir::populateFuncToEmitCPatterns(const TypeConverter &typeConverter,165 RewritePatternSet &patterns) {166 MLIRContext *ctx = patterns.getContext();167 168 patterns.add<CallOpConversion, FuncOpConversion, ReturnOpConversion>(169 typeConverter, ctx);170}171