llvm-project/mlir/lib/Parser/DialectSymbolParser.cpp

355 lines
13 KiB
C++

//===- DialectSymbolParser.cpp - MLIR Dialect Symbol Parser --------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// This file implements the parser for the dialect symbols, such as extended
// attributes and types.
//
//===----------------------------------------------------------------------===//
#include "AsmParserImpl.h"
#include "mlir/IR/BuiltinTypes.h"
#include "mlir/IR/Dialect.h"
#include "mlir/IR/DialectImplementation.h"
#include "llvm/Support/SourceMgr.h"
using namespace mlir;
using namespace mlir::detail;
using llvm::MemoryBuffer;
using llvm::SourceMgr;
namespace {
/// This class provides the main implementation of the DialectAsmParser that
/// allows for dialects to parse attributes and types. This allows for dialect
/// hooking into the main MLIR parsing logic.
class CustomDialectAsmParser : public AsmParserImpl<DialectAsmParser> {
public:
CustomDialectAsmParser(StringRef fullSpec, Parser &parser)
: AsmParserImpl<DialectAsmParser>(parser.getToken().getLoc(), parser),
fullSpec(fullSpec) {}
~CustomDialectAsmParser() override = default;
/// Returns the full specification of the symbol being parsed. This allows
/// for using a separate parser if necessary.
StringRef getFullSymbolSpec() const override { return fullSpec; }
private:
/// The full symbol specification.
StringRef fullSpec;
};
} // namespace
/// Parse the body of a pretty dialect symbol, which starts and ends with <>'s,
/// and may be recursive. Return with the 'prettyName' StringRef encompassing
/// the entire pretty name.
///
/// pretty-dialect-sym-body ::= '<' pretty-dialect-sym-contents+ '>'
/// pretty-dialect-sym-contents ::= pretty-dialect-sym-body
/// | '(' pretty-dialect-sym-contents+ ')'
/// | '[' pretty-dialect-sym-contents+ ']'
/// | '{' pretty-dialect-sym-contents+ '}'
/// | '[^[<({>\])}\0]+'
///
ParseResult Parser::parsePrettyDialectSymbolName(StringRef &prettyName) {
// Pretty symbol names are a relatively unstructured format that contains a
// series of properly nested punctuation, with anything else in the middle.
// Scan ahead to find it and consume it if successful, otherwise emit an
// error.
auto *curPtr = getTokenSpelling().data();
SmallVector<char, 8> nestedPunctuation;
// Scan over the nested punctuation, bailing out on error and consuming until
// we find the end. We know that we're currently looking at the '<', so we
// can go until we find the matching '>' character.
assert(*curPtr == '<');
do {
char c = *curPtr++;
switch (c) {
case '\0':
// This also handles the EOF case.
return emitError("unexpected nul or EOF in pretty dialect name");
case '<':
case '[':
case '(':
case '{':
nestedPunctuation.push_back(c);
continue;
case '-':
// The sequence `->` is treated as special token.
if (*curPtr == '>')
++curPtr;
continue;
case '>':
if (nestedPunctuation.pop_back_val() != '<')
return emitError("unbalanced '>' character in pretty dialect name");
break;
case ']':
if (nestedPunctuation.pop_back_val() != '[')
return emitError("unbalanced ']' character in pretty dialect name");
break;
case ')':
if (nestedPunctuation.pop_back_val() != '(')
return emitError("unbalanced ')' character in pretty dialect name");
break;
case '}':
if (nestedPunctuation.pop_back_val() != '{')
return emitError("unbalanced '}' character in pretty dialect name");
break;
default:
continue;
}
} while (!nestedPunctuation.empty());
// Ok, we succeeded, remember where we stopped, reset the lexer to know it is
// consuming all this stuff, and return.
state.lex.resetPointer(curPtr);
unsigned length = curPtr - prettyName.begin();
prettyName = StringRef(prettyName.begin(), length);
consumeToken();
return success();
}
/// Parse an extended dialect symbol.
template <typename Symbol, typename SymbolAliasMap, typename CreateFn>
static Symbol parseExtendedSymbol(Parser &p, Token::Kind identifierTok,
SymbolAliasMap &aliases,
CreateFn &&createSymbol) {
// Parse the dialect namespace.
StringRef identifier = p.getTokenSpelling().drop_front();
auto loc = p.getToken().getLoc();
p.consumeToken(identifierTok);
// If there is no '<' token following this, and if the typename contains no
// dot, then we are parsing a symbol alias.
if (p.getToken().isNot(Token::less) && !identifier.contains('.')) {
// Check for an alias for this type.
auto aliasIt = aliases.find(identifier);
if (aliasIt == aliases.end())
return (p.emitError("undefined symbol alias id '" + identifier + "'"),
nullptr);
return aliasIt->second;
}
// Otherwise, we are parsing a dialect-specific symbol. If the name contains
// a dot, then this is the "pretty" form. If not, it is the verbose form that
// looks like <"...">.
std::string symbolData;
auto dialectName = identifier;
// Handle the verbose form, where "identifier" is a simple dialect name.
if (!identifier.contains('.')) {
// Consume the '<'.
if (p.parseToken(Token::less, "expected '<' in dialect type"))
return nullptr;
// Parse the symbol specific data.
if (p.getToken().isNot(Token::string))
return (p.emitError("expected string literal data in dialect symbol"),
nullptr);
symbolData = p.getToken().getStringValue();
loc = SMLoc::getFromPointer(p.getToken().getLoc().getPointer() + 1);
p.consumeToken(Token::string);
// Consume the '>'.
if (p.parseToken(Token::greater, "expected '>' in dialect symbol"))
return nullptr;
} else {
// Ok, the dialect name is the part of the identifier before the dot, the
// part after the dot is the dialect's symbol, or the start thereof.
auto dotHalves = identifier.split('.');
dialectName = dotHalves.first;
auto prettyName = dotHalves.second;
loc = SMLoc::getFromPointer(prettyName.data());
// If the dialect's symbol is followed immediately by a <, then lex the body
// of it into prettyName.
if (p.getToken().is(Token::less) &&
prettyName.bytes_end() == p.getTokenSpelling().bytes_begin()) {
if (p.parsePrettyDialectSymbolName(prettyName))
return nullptr;
}
symbolData = prettyName.str();
}
// Record the name location of the type remapped to the top level buffer.
SMLoc locInTopLevelBuffer = p.remapLocationToTopLevelBuffer(loc);
p.getState().symbols.nestedParserLocs.push_back(locInTopLevelBuffer);
// Call into the provided symbol construction function.
Symbol sym = createSymbol(dialectName, symbolData, loc);
// Pop the last parser location.
p.getState().symbols.nestedParserLocs.pop_back();
return sym;
}
/// Parses a symbol, of type 'T', and returns it if parsing was successful. If
/// parsing failed, nullptr is returned. The number of bytes read from the input
/// string is returned in 'numRead'.
template <typename T, typename ParserFn>
static T parseSymbol(StringRef inputStr, MLIRContext *context,
SymbolState &symbolState, ParserFn &&parserFn,
size_t *numRead = nullptr) {
SourceMgr sourceMgr;
auto memBuffer = MemoryBuffer::getMemBuffer(
inputStr, /*BufferName=*/"<mlir_parser_buffer>",
/*RequiresNullTerminator=*/false);
sourceMgr.AddNewSourceBuffer(std::move(memBuffer), SMLoc());
ParserState state(sourceMgr, context, symbolState, /*asmState=*/nullptr);
Parser parser(state);
Token startTok = parser.getToken();
T symbol = parserFn(parser);
if (!symbol)
return T();
// If 'numRead' is valid, then provide the number of bytes that were read.
Token endTok = parser.getToken();
if (numRead) {
*numRead = static_cast<size_t>(endTok.getLoc().getPointer() -
startTok.getLoc().getPointer());
// Otherwise, ensure that all of the tokens were parsed.
} else if (startTok.getLoc() != endTok.getLoc() && endTok.isNot(Token::eof)) {
parser.emitError(endTok.getLoc(), "encountered unexpected token");
return T();
}
return symbol;
}
/// Parse an extended attribute.
///
/// extended-attribute ::= (dialect-attribute | attribute-alias)
/// dialect-attribute ::= `#` dialect-namespace `<` `"` attr-data `"` `>`
/// dialect-attribute ::= `#` alias-name pretty-dialect-sym-body?
/// attribute-alias ::= `#` alias-name
///
Attribute Parser::parseExtendedAttr(Type type) {
Attribute attr = parseExtendedSymbol<Attribute>(
*this, Token::hash_identifier, state.symbols.attributeAliasDefinitions,
[&](StringRef dialectName, StringRef symbolData,
SMLoc loc) -> Attribute {
// Parse an optional trailing colon type.
Type attrType = type;
if (consumeIf(Token::colon) && !(attrType = parseType()))
return Attribute();
// If we found a registered dialect, then ask it to parse the attribute.
if (Dialect *dialect =
builder.getContext()->getOrLoadDialect(dialectName)) {
return parseSymbol<Attribute>(
symbolData, state.context, state.symbols, [&](Parser &parser) {
CustomDialectAsmParser customParser(symbolData, parser);
return dialect->parseAttribute(customParser, attrType);
});
}
// Otherwise, form a new opaque attribute.
return OpaqueAttr::getChecked(
[&] { return emitError(loc); },
StringAttr::get(state.context, dialectName), symbolData,
attrType ? attrType : NoneType::get(state.context));
});
// Ensure that the attribute has the same type as requested.
if (attr && type && attr.getType() != type) {
emitError("attribute type different than expected: expected ")
<< type << ", but got " << attr.getType();
return nullptr;
}
return attr;
}
/// Parse an extended type.
///
/// extended-type ::= (dialect-type | type-alias)
/// dialect-type ::= `!` dialect-namespace `<` `"` type-data `"` `>`
/// dialect-type ::= `!` alias-name pretty-dialect-attribute-body?
/// type-alias ::= `!` alias-name
///
Type Parser::parseExtendedType() {
return parseExtendedSymbol<Type>(
*this, Token::exclamation_identifier, state.symbols.typeAliasDefinitions,
[&](StringRef dialectName, StringRef symbolData,
SMLoc loc) -> Type {
// If we found a registered dialect, then ask it to parse the type.
auto *dialect = state.context->getOrLoadDialect(dialectName);
if (dialect) {
return parseSymbol<Type>(
symbolData, state.context, state.symbols, [&](Parser &parser) {
CustomDialectAsmParser customParser(symbolData, parser);
return dialect->parseType(customParser);
});
}
// Otherwise, form a new opaque type.
return OpaqueType::getChecked(
[&] { return emitError(loc); },
StringAttr::get(state.context, dialectName), symbolData);
});
}
//===----------------------------------------------------------------------===//
// mlir::parseAttribute/parseType
//===----------------------------------------------------------------------===//
/// Parses a symbol, of type 'T', and returns it if parsing was successful. If
/// parsing failed, nullptr is returned. The number of bytes read from the input
/// string is returned in 'numRead'.
template <typename T, typename ParserFn>
static T parseSymbol(StringRef inputStr, MLIRContext *context, size_t &numRead,
ParserFn &&parserFn) {
SymbolState aliasState;
return parseSymbol<T>(
inputStr, context, aliasState,
[&](Parser &parser) {
SourceMgrDiagnosticHandler handler(
const_cast<llvm::SourceMgr &>(parser.getSourceMgr()),
parser.getContext());
return parserFn(parser);
},
&numRead);
}
Attribute mlir::parseAttribute(StringRef attrStr, MLIRContext *context) {
size_t numRead = 0;
return parseAttribute(attrStr, context, numRead);
}
Attribute mlir::parseAttribute(StringRef attrStr, Type type) {
size_t numRead = 0;
return parseAttribute(attrStr, type, numRead);
}
Attribute mlir::parseAttribute(StringRef attrStr, MLIRContext *context,
size_t &numRead) {
return parseSymbol<Attribute>(attrStr, context, numRead, [](Parser &parser) {
return parser.parseAttribute();
});
}
Attribute mlir::parseAttribute(StringRef attrStr, Type type, size_t &numRead) {
return parseSymbol<Attribute>(
attrStr, type.getContext(), numRead,
[type](Parser &parser) { return parser.parseAttribute(type); });
}
Type mlir::parseType(StringRef typeStr, MLIRContext *context) {
size_t numRead = 0;
return parseType(typeStr, context, numRead);
}
Type mlir::parseType(StringRef typeStr, MLIRContext *context, size_t &numRead) {
return parseSymbol<Type>(typeStr, context, numRead,
[](Parser &parser) { return parser.parseType(); });
}