1 //===- FunctionImplementation.cpp - Utilities for function-like ops -------===//
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-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #include "mlir/IR/FunctionImplementation.h"
10 #include "mlir/IR/Builders.h"
11 #include "mlir/IR/FunctionSupport.h"
12 #include "mlir/IR/SymbolTable.h"
13
14 using namespace mlir;
15
parseFunctionArgumentList(OpAsmParser & parser,bool allowAttributes,bool allowVariadic,SmallVectorImpl<OpAsmParser::OperandType> & argNames,SmallVectorImpl<Type> & argTypes,SmallVectorImpl<NamedAttrList> & argAttrs,bool & isVariadic)16 ParseResult mlir::impl::parseFunctionArgumentList(
17 OpAsmParser &parser, bool allowAttributes, bool allowVariadic,
18 SmallVectorImpl<OpAsmParser::OperandType> &argNames,
19 SmallVectorImpl<Type> &argTypes, SmallVectorImpl<NamedAttrList> &argAttrs,
20 bool &isVariadic) {
21 if (parser.parseLParen())
22 return failure();
23
24 // The argument list either has to consistently have ssa-id's followed by
25 // types, or just be a type list. It isn't ok to sometimes have SSA ID's and
26 // sometimes not.
27 auto parseArgument = [&]() -> ParseResult {
28 llvm::SMLoc loc = parser.getCurrentLocation();
29
30 // Parse argument name if present.
31 OpAsmParser::OperandType argument;
32 Type argumentType;
33 if (succeeded(parser.parseOptionalRegionArgument(argument)) &&
34 !argument.name.empty()) {
35 // Reject this if the preceding argument was missing a name.
36 if (argNames.empty() && !argTypes.empty())
37 return parser.emitError(loc, "expected type instead of SSA identifier");
38 argNames.push_back(argument);
39
40 if (parser.parseColonType(argumentType))
41 return failure();
42 } else if (allowVariadic && succeeded(parser.parseOptionalEllipsis())) {
43 isVariadic = true;
44 return success();
45 } else if (!argNames.empty()) {
46 // Reject this if the preceding argument had a name.
47 return parser.emitError(loc, "expected SSA identifier");
48 } else if (parser.parseType(argumentType)) {
49 return failure();
50 }
51
52 // Add the argument type.
53 argTypes.push_back(argumentType);
54
55 // Parse any argument attributes.
56 NamedAttrList attrs;
57 if (parser.parseOptionalAttrDict(attrs))
58 return failure();
59 if (!allowAttributes && !attrs.empty())
60 return parser.emitError(loc, "expected arguments without attributes");
61 argAttrs.push_back(attrs);
62 return success();
63 };
64
65 // Parse the function arguments.
66 isVariadic = false;
67 if (failed(parser.parseOptionalRParen())) {
68 do {
69 unsigned numTypedArguments = argTypes.size();
70 if (parseArgument())
71 return failure();
72
73 llvm::SMLoc loc = parser.getCurrentLocation();
74 if (argTypes.size() == numTypedArguments &&
75 succeeded(parser.parseOptionalComma()))
76 return parser.emitError(
77 loc, "variadic arguments must be in the end of the argument list");
78 } while (succeeded(parser.parseOptionalComma()));
79 parser.parseRParen();
80 }
81
82 return success();
83 }
84
85 /// Parse a function result list.
86 ///
87 /// function-result-list ::= function-result-list-parens
88 /// | non-function-type
89 /// function-result-list-parens ::= `(` `)`
90 /// | `(` function-result-list-no-parens `)`
91 /// function-result-list-no-parens ::= function-result (`,` function-result)*
92 /// function-result ::= type attribute-dict?
93 ///
94 static ParseResult
parseFunctionResultList(OpAsmParser & parser,SmallVectorImpl<Type> & resultTypes,SmallVectorImpl<NamedAttrList> & resultAttrs)95 parseFunctionResultList(OpAsmParser &parser, SmallVectorImpl<Type> &resultTypes,
96 SmallVectorImpl<NamedAttrList> &resultAttrs) {
97 if (failed(parser.parseOptionalLParen())) {
98 // We already know that there is no `(`, so parse a type.
99 // Because there is no `(`, it cannot be a function type.
100 Type ty;
101 if (parser.parseType(ty))
102 return failure();
103 resultTypes.push_back(ty);
104 resultAttrs.emplace_back();
105 return success();
106 }
107
108 // Special case for an empty set of parens.
109 if (succeeded(parser.parseOptionalRParen()))
110 return success();
111
112 // Parse individual function results.
113 do {
114 resultTypes.emplace_back();
115 resultAttrs.emplace_back();
116 if (parser.parseType(resultTypes.back()) ||
117 parser.parseOptionalAttrDict(resultAttrs.back())) {
118 return failure();
119 }
120 } while (succeeded(parser.parseOptionalComma()));
121 return parser.parseRParen();
122 }
123
124 /// Parses a function signature using `parser`. The `allowVariadic` argument
125 /// indicates whether functions with variadic arguments are supported. The
126 /// trailing arguments are populated by this function with names, types and
127 /// attributes of the arguments and those of the results.
parseFunctionSignature(OpAsmParser & parser,bool allowVariadic,SmallVectorImpl<OpAsmParser::OperandType> & argNames,SmallVectorImpl<Type> & argTypes,SmallVectorImpl<NamedAttrList> & argAttrs,bool & isVariadic,SmallVectorImpl<Type> & resultTypes,SmallVectorImpl<NamedAttrList> & resultAttrs)128 ParseResult mlir::impl::parseFunctionSignature(
129 OpAsmParser &parser, bool allowVariadic,
130 SmallVectorImpl<OpAsmParser::OperandType> &argNames,
131 SmallVectorImpl<Type> &argTypes, SmallVectorImpl<NamedAttrList> &argAttrs,
132 bool &isVariadic, SmallVectorImpl<Type> &resultTypes,
133 SmallVectorImpl<NamedAttrList> &resultAttrs) {
134 bool allowArgAttrs = true;
135 if (parseFunctionArgumentList(parser, allowArgAttrs, allowVariadic, argNames,
136 argTypes, argAttrs, isVariadic))
137 return failure();
138 if (succeeded(parser.parseOptionalArrow()))
139 return parseFunctionResultList(parser, resultTypes, resultAttrs);
140 return success();
141 }
142
addArgAndResultAttrs(Builder & builder,OperationState & result,ArrayRef<NamedAttrList> argAttrs,ArrayRef<NamedAttrList> resultAttrs)143 void mlir::impl::addArgAndResultAttrs(Builder &builder, OperationState &result,
144 ArrayRef<NamedAttrList> argAttrs,
145 ArrayRef<NamedAttrList> resultAttrs) {
146 // Add the attributes to the function arguments.
147 SmallString<8> attrNameBuf;
148 for (unsigned i = 0, e = argAttrs.size(); i != e; ++i)
149 if (!argAttrs[i].empty())
150 result.addAttribute(getArgAttrName(i, attrNameBuf),
151 builder.getDictionaryAttr(argAttrs[i]));
152
153 // Add the attributes to the function results.
154 for (unsigned i = 0, e = resultAttrs.size(); i != e; ++i)
155 if (!resultAttrs[i].empty())
156 result.addAttribute(getResultAttrName(i, attrNameBuf),
157 builder.getDictionaryAttr(resultAttrs[i]));
158 }
159
160 /// Parser implementation for function-like operations. Uses `funcTypeBuilder`
161 /// to construct the custom function type given lists of input and output types.
162 ParseResult
parseFunctionLikeOp(OpAsmParser & parser,OperationState & result,bool allowVariadic,mlir::impl::FuncTypeBuilder funcTypeBuilder)163 mlir::impl::parseFunctionLikeOp(OpAsmParser &parser, OperationState &result,
164 bool allowVariadic,
165 mlir::impl::FuncTypeBuilder funcTypeBuilder) {
166 SmallVector<OpAsmParser::OperandType, 4> entryArgs;
167 SmallVector<NamedAttrList, 4> argAttrs;
168 SmallVector<NamedAttrList, 4> resultAttrs;
169 SmallVector<Type, 4> argTypes;
170 SmallVector<Type, 4> resultTypes;
171 auto &builder = parser.getBuilder();
172
173 // Parse visibility.
174 impl::parseOptionalVisibilityKeyword(parser, result.attributes);
175
176 // Parse the name as a symbol.
177 StringAttr nameAttr;
178 if (parser.parseSymbolName(nameAttr, SymbolTable::getSymbolAttrName(),
179 result.attributes))
180 return failure();
181
182 // Parse the function signature.
183 auto signatureLocation = parser.getCurrentLocation();
184 bool isVariadic = false;
185 if (parseFunctionSignature(parser, allowVariadic, entryArgs, argTypes,
186 argAttrs, isVariadic, resultTypes, resultAttrs))
187 return failure();
188
189 std::string errorMessage;
190 if (auto type = funcTypeBuilder(builder, argTypes, resultTypes,
191 impl::VariadicFlag(isVariadic), errorMessage))
192 result.addAttribute(getTypeAttrName(), TypeAttr::get(type));
193 else
194 return parser.emitError(signatureLocation)
195 << "failed to construct function type"
196 << (errorMessage.empty() ? "" : ": ") << errorMessage;
197
198 // If function attributes are present, parse them.
199 if (parser.parseOptionalAttrDictWithKeyword(result.attributes))
200 return failure();
201
202 // Add the attributes to the function arguments.
203 assert(argAttrs.size() == argTypes.size());
204 assert(resultAttrs.size() == resultTypes.size());
205 addArgAndResultAttrs(builder, result, argAttrs, resultAttrs);
206
207 // Parse the optional function body. The printer will not print the body if
208 // its empty, so disallow parsing of empty body in the parser.
209 auto *body = result.addRegion();
210 llvm::SMLoc loc = parser.getCurrentLocation();
211 OptionalParseResult parseResult = parser.parseOptionalRegion(
212 *body, entryArgs, entryArgs.empty() ? ArrayRef<Type>() : argTypes,
213 /*enableNameShadowing=*/false);
214 if (parseResult.hasValue()) {
215 if (failed(*parseResult))
216 return failure();
217 // Function body was parsed, make sure its not empty.
218 if (body->empty())
219 return parser.emitError(loc, "expected non-empty function body");
220 }
221 return success();
222 }
223
224 // Print a function result list.
printFunctionResultList(OpAsmPrinter & p,ArrayRef<Type> types,ArrayRef<ArrayRef<NamedAttribute>> attrs)225 static void printFunctionResultList(OpAsmPrinter &p, ArrayRef<Type> types,
226 ArrayRef<ArrayRef<NamedAttribute>> attrs) {
227 assert(!types.empty() && "Should not be called for empty result list.");
228 auto &os = p.getStream();
229 bool needsParens =
230 types.size() > 1 || types[0].isa<FunctionType>() || !attrs[0].empty();
231 if (needsParens)
232 os << '(';
233 llvm::interleaveComma(
234 llvm::zip(types, attrs), os,
235 [&](const std::tuple<Type, ArrayRef<NamedAttribute>> &t) {
236 p.printType(std::get<0>(t));
237 p.printOptionalAttrDict(std::get<1>(t));
238 });
239 if (needsParens)
240 os << ')';
241 }
242
243 /// Print the signature of the function-like operation `op`. Assumes `op` has
244 /// the FunctionLike trait and passed the verification.
printFunctionSignature(OpAsmPrinter & p,Operation * op,ArrayRef<Type> argTypes,bool isVariadic,ArrayRef<Type> resultTypes)245 void mlir::impl::printFunctionSignature(OpAsmPrinter &p, Operation *op,
246 ArrayRef<Type> argTypes,
247 bool isVariadic,
248 ArrayRef<Type> resultTypes) {
249 Region &body = op->getRegion(0);
250 bool isExternal = body.empty();
251
252 p << '(';
253 for (unsigned i = 0, e = argTypes.size(); i < e; ++i) {
254 if (i > 0)
255 p << ", ";
256
257 if (!isExternal) {
258 p.printOperand(body.getArgument(i));
259 p << ": ";
260 }
261
262 p.printType(argTypes[i]);
263 p.printOptionalAttrDict(::mlir::impl::getArgAttrs(op, i));
264 }
265
266 if (isVariadic) {
267 if (!argTypes.empty())
268 p << ", ";
269 p << "...";
270 }
271
272 p << ')';
273
274 if (!resultTypes.empty()) {
275 p.getStream() << " -> ";
276 SmallVector<ArrayRef<NamedAttribute>, 4> resultAttrs;
277 for (int i = 0, e = resultTypes.size(); i < e; ++i)
278 resultAttrs.push_back(::mlir::impl::getResultAttrs(op, i));
279 printFunctionResultList(p, resultTypes, resultAttrs);
280 }
281 }
282
283 /// Prints the list of function prefixed with the "attributes" keyword. The
284 /// attributes with names listed in "elided" as well as those used by the
285 /// function-like operation internally are not printed. Nothing is printed
286 /// if all attributes are elided. Assumes `op` has the `FunctionLike` trait and
287 /// passed the verification.
printFunctionAttributes(OpAsmPrinter & p,Operation * op,unsigned numInputs,unsigned numResults,ArrayRef<StringRef> elided)288 void mlir::impl::printFunctionAttributes(OpAsmPrinter &p, Operation *op,
289 unsigned numInputs,
290 unsigned numResults,
291 ArrayRef<StringRef> elided) {
292 // Print out function attributes, if present.
293 SmallVector<StringRef, 2> ignoredAttrs = {
294 ::mlir::SymbolTable::getSymbolAttrName(), getTypeAttrName()};
295 ignoredAttrs.append(elided.begin(), elided.end());
296
297 SmallString<8> attrNameBuf;
298
299 // Ignore any argument attributes.
300 std::vector<SmallString<8>> argAttrStorage;
301 for (unsigned i = 0; i != numInputs; ++i)
302 if (op->getAttr(getArgAttrName(i, attrNameBuf)))
303 argAttrStorage.emplace_back(attrNameBuf);
304 ignoredAttrs.append(argAttrStorage.begin(), argAttrStorage.end());
305
306 // Ignore any result attributes.
307 std::vector<SmallString<8>> resultAttrStorage;
308 for (unsigned i = 0; i != numResults; ++i)
309 if (op->getAttr(getResultAttrName(i, attrNameBuf)))
310 resultAttrStorage.emplace_back(attrNameBuf);
311 ignoredAttrs.append(resultAttrStorage.begin(), resultAttrStorage.end());
312
313 p.printOptionalAttrDictWithKeyword(op->getAttrs(), ignoredAttrs);
314 }
315
316 /// Printer implementation for function-like operations. Accepts lists of
317 /// argument and result types to use while printing.
printFunctionLikeOp(OpAsmPrinter & p,Operation * op,ArrayRef<Type> argTypes,bool isVariadic,ArrayRef<Type> resultTypes)318 void mlir::impl::printFunctionLikeOp(OpAsmPrinter &p, Operation *op,
319 ArrayRef<Type> argTypes, bool isVariadic,
320 ArrayRef<Type> resultTypes) {
321 // Print the operation and the function name.
322 auto funcName =
323 op->getAttrOfType<StringAttr>(SymbolTable::getSymbolAttrName())
324 .getValue();
325 p << op->getName() << ' ';
326
327 StringRef visibilityAttrName = SymbolTable::getVisibilityAttrName();
328 if (auto visibility = op->getAttrOfType<StringAttr>(visibilityAttrName))
329 p << visibility.getValue() << ' ';
330 p.printSymbolName(funcName);
331
332 printFunctionSignature(p, op, argTypes, isVariadic, resultTypes);
333 printFunctionAttributes(p, op, argTypes.size(), resultTypes.size(),
334 {visibilityAttrName});
335 // Print the body if this is not an external function.
336 Region &body = op->getRegion(0);
337 if (!body.empty())
338 p.printRegion(body, /*printEntryBlockArgs=*/false,
339 /*printBlockTerminators=*/true);
340 }
341