/build/source/mlir/lib/AsmParser/Parser.cpp

Bug Summary

File:	build/source/mlir/lib/AsmParser/Parser.cpp
Warning:	line 1229, column 5 1st function call argument is an uninitialized value
Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name Parser.cpp -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/source/build-llvm/tools/clang/stage2-bins -resource-dir /usr/lib/llvm-17/lib/clang/17 -D MLIR_CUDA_CONVERSIONS_ENABLED=1 -D MLIR_ROCM_CONVERSIONS_ENABLED=1 -D _DEBUG -D _GLIBCXX_ASSERTIONS -D _GNU_SOURCE -D _LIBCPP_ENABLE_ASSERTIONS -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I tools/mlir/lib/AsmParser -I /build/source/mlir/lib/AsmParser -I include -I /build/source/llvm/include -I /build/source/mlir/include -I tools/mlir/include -D _FORTIFY_SOURCE=2 -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-17/lib/clang/17/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/build/source/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fmacro-prefix-map=/build/source/= -fcoverage-prefix-map=/build/source/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fcoverage-prefix-map=/build/source/= -source-date-epoch 1683717183 -O2 -Wno-unused-command-line-argument -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -Wno-misleading-indentation -std=c++17 -fdeprecated-macro -fdebug-compilation-dir=/build/source/build-llvm/tools/clang/stage2-bins -fdebug-prefix-map=/build/source/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fdebug-prefix-map=/build/source/= -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2023-05-10-133810-16478-1 -x c++ /build/source/mlir/lib/AsmParser/Parser.cpp
1//===- Parser.cpp - MLIR Parser Implementation ----------------------------===//
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// This file implements the parser for the MLIR textual form.
10//
11//===----------------------------------------------------------------------===//

13#include "Parser.h"
14#include "AsmParserImpl.h"
15#include "mlir/AsmParser/AsmParser.h"
16#include "mlir/AsmParser/AsmParserState.h"
17#include "mlir/AsmParser/CodeComplete.h"
18#include "mlir/IR/AffineMap.h"
19#include "mlir/IR/AsmState.h"
20#include "mlir/IR/BuiltinOps.h"
21#include "mlir/IR/Dialect.h"
22#include "mlir/IR/Verifier.h"
23#include "llvm/ADT/DenseMap.h"
24#include "llvm/ADT/ScopeExit.h"
25#include "llvm/ADT/StringSet.h"
26#include "llvm/ADT/bit.h"
27#include "llvm/Support/Endian.h"
28#include "llvm/Support/PrettyStackTrace.h"
29#include "llvm/Support/SourceMgr.h"
30#include <algorithm>
31#include <optional>

33using namespace mlir;
34using namespace mlir::detail;

36//===----------------------------------------------------------------------===//
37// CodeComplete
38//===----------------------------------------------------------------------===//

40AsmParserCodeCompleteContext::~AsmParserCodeCompleteContext() = default;

42//===----------------------------------------------------------------------===//
43// Parser
44//===----------------------------------------------------------------------===//

46/// Parse a list of comma-separated items with an optional delimiter.  If a
47/// delimiter is provided, then an empty list is allowed.  If not, then at
48/// least one element will be parsed.
49ParseResult
50Parser::parseCommaSeparatedList(Delimiter delimiter,
                              function_ref<ParseResult()> parseElementFn,
                              StringRef contextMessage) {
switch (delimiter) {
case Delimiter::None:
  break;
case Delimiter::OptionalParen:
  if (getToken().isNot(Token::l_paren))
    return success();
  [[fallthrough]];
case Delimiter::Paren:
  if (parseToken(Token::l_paren, "expected '('" + contextMessage))
    return failure();
  // Check for empty list.
  if (consumeIf(Token::r_paren))
    return success();
  break;
case Delimiter::OptionalLessGreater:
  // Check for absent list.
  if (getToken().isNot(Token::less))
    return success();
  [[fallthrough]];
case Delimiter::LessGreater:
  if (parseToken(Token::less, "expected '<'" + contextMessage))
    return success();
  // Check for empty list.
  if (consumeIf(Token::greater))
    return success();
  break;
case Delimiter::OptionalSquare:
  if (getToken().isNot(Token::l_square))
    return success();
  [[fallthrough]];
case Delimiter::Square:
  if (parseToken(Token::l_square, "expected '['" + contextMessage))
    return failure();
  // Check for empty list.
  if (consumeIf(Token::r_square))
    return success();
  break;
case Delimiter::OptionalBraces:
  if (getToken().isNot(Token::l_brace))
    return success();
  [[fallthrough]];
case Delimiter::Braces:
  if (parseToken(Token::l_brace, "expected '{'" + contextMessage))
    return failure();
  // Check for empty list.
  if (consumeIf(Token::r_brace))
    return success();
  break;
}

// Non-empty case starts with an element.
if (parseElementFn())
  return failure();

// Otherwise we have a list of comma separated elements.
while (consumeIf(Token::comma)) {
  if (parseElementFn())
    return failure();
}

switch (delimiter) {
case Delimiter::None:
  return success();
case Delimiter::OptionalParen:
case Delimiter::Paren:
  return parseToken(Token::r_paren, "expected ')'" + contextMessage);
case Delimiter::OptionalLessGreater:
case Delimiter::LessGreater:
  return parseToken(Token::greater, "expected '>'" + contextMessage);
case Delimiter::OptionalSquare:
case Delimiter::Square:
  return parseToken(Token::r_square, "expected ']'" + contextMessage);
case Delimiter::OptionalBraces:
case Delimiter::Braces:
  return parseToken(Token::r_brace, "expected '}'" + contextMessage);
}
llvm_unreachable("Unknown delimiter")::llvm::llvm_unreachable_internal("Unknown delimiter", "mlir/lib/AsmParser/Parser.cpp"
, 129);
130}

132/// Parse a comma-separated list of elements, terminated with an arbitrary
133/// token.  This allows empty lists if allowEmptyList is true.
134///
135///   abstract-list ::= rightToken                  // if allowEmptyList == true
136///   abstract-list ::= element (',' element)* rightToken
137///
138ParseResult
139Parser::parseCommaSeparatedListUntil(Token::Kind rightToken,
                                   function_ref<ParseResult()> parseElement,
                                   bool allowEmptyList) {
// Handle the empty case.
if (getToken().is(rightToken)) {
  if (!allowEmptyList)
    return emitWrongTokenError("expected list element");
  consumeToken(rightToken);
  return success();
}

if (parseCommaSeparatedList(parseElement) ||
    parseToken(rightToken, "expected ',' or '" +
                               Token::getTokenSpelling(rightToken) + "'"))
  return failure();

return success();
156}

158InFlightDiagnostic Parser::emitError(const Twine &message) {
auto loc = state.curToken.getLoc();
if (state.curToken.isNot(Token::eof))
  return emitError(loc, message);

// If the error is to be emitted at EOF, move it back one character.
return emitError(SMLoc::getFromPointer(loc.getPointer() - 1), message);
165}

167InFlightDiagnostic Parser::emitError(SMLoc loc, const Twine &message) {
auto diag = mlir::emitError(getEncodedSourceLocation(loc), message);

// If we hit a parse error in response to a lexer error, then the lexer
// already reported the error.
if (getToken().is(Token::error))
  diag.abandon();
return diag;
175}

177/// Emit an error about a "wrong token".  If the current token is at the
178/// start of a source line, this will apply heuristics to back up and report
179/// the error at the end of the previous line, which is where the expected
180/// token is supposed to be.
181InFlightDiagnostic Parser::emitWrongTokenError(const Twine &message) {
auto loc = state.curToken.getLoc();

// If the error is to be emitted at EOF, move it back one character.
if (state.curToken.is(Token::eof))
  loc = SMLoc::getFromPointer(loc.getPointer() - 1);

// This is the location we were originally asked to report the error at.
auto originalLoc = loc;

// Determine if the token is at the start of the current line.
const char *bufferStart = state.lex.getBufferBegin();
const char *curPtr = loc.getPointer();

// Use this StringRef to keep track of what we are going to back up through,
// it provides nicer string search functions etc.
StringRef startOfBuffer(bufferStart, curPtr - bufferStart);

// Back up over entirely blank lines.
while (true) {
  // Back up until we see a \n, but don't look past the buffer start.
  startOfBuffer = startOfBuffer.rtrim(" \t");

  // For tokens with no preceding source line, just emit at the original
  // location.
  if (startOfBuffer.empty())
    return emitError(originalLoc, message);

  // If we found something that isn't the end of line, then we're done.
  if (startOfBuffer.back() != '\n' && startOfBuffer.back() != '\r')
    return emitError(SMLoc::getFromPointer(startOfBuffer.end()), message);

  // Drop the \n so we emit the diagnostic at the end of the line.
  startOfBuffer = startOfBuffer.drop_back();

  // Check to see if the preceding line has a comment on it.  We assume that a
  // `//` is the start of a comment, which is mostly correct.
  // TODO: This will do the wrong thing for // in a string literal.
  auto prevLine = startOfBuffer;
  size_t newLineIndex = prevLine.find_last_of("\n\r");
  if (newLineIndex != StringRef::npos)
    prevLine = prevLine.drop_front(newLineIndex);

  // If we find a // in the current line, then emit the diagnostic before it.
  size_t commentStart = prevLine.find("//");
  if (commentStart != StringRef::npos)
    startOfBuffer = startOfBuffer.drop_back(prevLine.size() - commentStart);
}
229}

231/// Consume the specified token if present and return success.  On failure,
232/// output a diagnostic and return failure.
233ParseResult Parser::parseToken(Token::Kind expectedToken,
                             const Twine &message) {
if (consumeIf(expectedToken))
  return success();
return emitWrongTokenError(message);
238}

240/// Parse an optional integer value from the stream.
241OptionalParseResult Parser::parseOptionalInteger(APInt &result) {
// Parse `false` and `true` keywords as 0 and 1 respectively.
if (consumeIf(Token::kw_false)) {
  result = false;
  return success();
}
if (consumeIf(Token::kw_true)) {
  result = true;
  return success();
}

Token curToken = getToken();
if (curToken.isNot(Token::integer, Token::minus))
  return std::nullopt;

bool negative = consumeIf(Token::minus);
Token curTok = getToken();
if (parseToken(Token::integer, "expected integer value"))
  return failure();

StringRef spelling = curTok.getSpelling();
bool isHex = spelling.size() > 1 && spelling[1] == 'x';
if (spelling.getAsInteger(isHex ? 0 : 10, result))
  return emitError(curTok.getLoc(), "integer value too large");

// Make sure we have a zero at the top so we return the right signedness.
if (result.isNegative())
  result = result.zext(result.getBitWidth() + 1);

// Process the negative sign if present.
if (negative)
  result.negate();

return success();
275}

277/// Parse a floating point value from an integer literal token.
278ParseResult Parser::parseFloatFromIntegerLiteral(
  std::optional<APFloat> &result, const Token &tok, bool isNegative,
  const llvm::fltSemantics &semantics, size_t typeSizeInBits) {
SMLoc loc = tok.getLoc();
StringRef spelling = tok.getSpelling();
bool isHex = spelling.size() > 1 && spelling[1] == 'x';
if (!isHex) {
  return emitError(loc, "unexpected decimal integer literal for a "
                        "floating point value")
             .attachNote()
         << "add a trailing dot to make the literal a float";
}
if (isNegative) {
  return emitError(loc, "hexadecimal float literal should not have a "
                        "leading minus");
}

std::optional<uint64_t> value = tok.getUInt64IntegerValue();
if (!value)
  return emitError(loc, "hexadecimal float constant out of range for type");

if (&semantics == &APFloat::IEEEdouble()) {
  result = APFloat(semantics, APInt(typeSizeInBits, *value));
  return success();
}

APInt apInt(typeSizeInBits, *value);
if (apInt != *value)
  return emitError(loc, "hexadecimal float constant out of range for type");
result = APFloat(semantics, apInt);

return success();
310}

312ParseResult Parser::parseOptionalKeyword(StringRef *keyword) {
// Check that the current token is a keyword.
if (!isCurrentTokenAKeyword())
  return failure();

*keyword = getTokenSpelling();
consumeToken();
return success();
320}

322//===----------------------------------------------------------------------===//
323// Resource Parsing

325FailureOr<AsmDialectResourceHandle>
326Parser::parseResourceHandle(const OpAsmDialectInterface *dialect,
                          StringRef &name) {
assert(dialect && "expected valid dialect interface")(static_cast <bool> (dialect && "expected valid dialect interface"
) ? void (0) : __assert_fail ("dialect && \"expected valid dialect interface\""
, "mlir/lib/AsmParser/Parser.cpp", 328, __extension__ __PRETTY_FUNCTION__
));
SMLoc nameLoc = getToken().getLoc();
if (failed(parseOptionalKeyword(&name)))
  return emitError("expected identifier key for 'resource' entry");
auto &resources = getState().symbols.dialectResources;

// If this is the first time encountering this handle, ask the dialect to
// resolve a reference to this handle. This allows for us to remap the name of
// the handle if necessary.
std::pair<std::string, AsmDialectResourceHandle> &entry =
    resources[dialect][name];
if (entry.first.empty()) {
  FailureOr<AsmDialectResourceHandle> result = dialect->declareResource(name);
  if (failed(result)) {
    return emitError(nameLoc)
           << "unknown 'resource' key '" << name << "' for dialect '"
           << dialect->getDialect()->getNamespace() << "'";
  }
  entry.first = dialect->getResourceKey(*result);
  entry.second = *result;
}

name = entry.first;
return entry.second;
352}

354FailureOr<AsmDialectResourceHandle>
355Parser::parseResourceHandle(Dialect *dialect) {
const auto *interface = dyn_cast<OpAsmDialectInterface>(dialect);
if (!interface) {
  return emitError() << "dialect '" << dialect->getNamespace()
                     << "' does not expect resource handles";
}
StringRef resourceName;
return parseResourceHandle(interface, resourceName);
363}

365//===----------------------------------------------------------------------===//
366// Code Completion

368ParseResult Parser::codeCompleteDialectName() {
state.codeCompleteContext->completeDialectName();
return failure();
371}

373ParseResult Parser::codeCompleteOperationName(StringRef dialectName) {
// Perform some simple validation on the dialect name. This doesn't need to be
// extensive, it's more of an optimization (to avoid checking completion
// results when we know they will fail).
if (dialectName.empty() || dialectName.contains('.'))
  return failure();
state.codeCompleteContext->completeOperationName(dialectName);
return failure();
381}

383ParseResult Parser::codeCompleteDialectOrElidedOpName(SMLoc loc) {
// Check to see if there is anything else on the current line. This check
// isn't strictly necessary, but it does avoid unnecessarily triggering
// completions for operations and dialects in situations where we don't want
// them (e.g. at the end of an operation).
auto shouldIgnoreOpCompletion = [&]() {
  const char *bufBegin = state.lex.getBufferBegin();
  const char *it = loc.getPointer() - 1;
  for (; it > bufBegin && *it != '\n'; --it)
    if (!StringRef(" \t\r").contains(*it))
      return true;
  return false;
};
if (shouldIgnoreOpCompletion())
  return failure();

// The completion here is either for a dialect name, or an operation name
// whose dialect prefix was elided. For this we simply invoke both of the
// individual completion methods.
(void)codeCompleteDialectName();
return codeCompleteOperationName(state.defaultDialectStack.back());
404}

406ParseResult Parser::codeCompleteStringDialectOrOperationName(StringRef name) {
// If the name is empty, this is the start of the string and contains the
// dialect.
if (name.empty())
  return codeCompleteDialectName();

// Otherwise, we treat this as completing an operation name. The current name
// is used as the dialect namespace.
if (name.consume_back("."))
  return codeCompleteOperationName(name);
return failure();
417}

419ParseResult Parser::codeCompleteExpectedTokens(ArrayRef<StringRef> tokens) {
state.codeCompleteContext->completeExpectedTokens(tokens, /*optional=*/false);
return failure();
422}
423ParseResult Parser::codeCompleteOptionalTokens(ArrayRef<StringRef> tokens) {
state.codeCompleteContext->completeExpectedTokens(tokens, /*optional=*/true);
return failure();
426}

428Attribute Parser::codeCompleteAttribute() {
state.codeCompleteContext->completeAttribute(
    state.symbols.attributeAliasDefinitions);
return {};
432}
433Type Parser::codeCompleteType() {
state.codeCompleteContext->completeType(state.symbols.typeAliasDefinitions);
return {};
436}

438Attribute
439Parser::codeCompleteDialectSymbol(const llvm::StringMap<Attribute> &aliases) {
state.codeCompleteContext->completeDialectAttributeOrAlias(aliases);
return {};
442}
443Type Parser::codeCompleteDialectSymbol(const llvm::StringMap<Type> &aliases) {
state.codeCompleteContext->completeDialectTypeOrAlias(aliases);
return {};
446}

448//===----------------------------------------------------------------------===//
449// OperationParser
450//===----------------------------------------------------------------------===//

452namespace {
453/// This class provides support for parsing operations and regions of
454/// operations.
455class OperationParser : public Parser {
456public:
OperationParser(ParserState &state, ModuleOp topLevelOp);
~OperationParser();

/// After parsing is finished, this function must be called to see if there
/// are any remaining issues.
ParseResult finalize();

//===--------------------------------------------------------------------===//
// SSA Value Handling
//===--------------------------------------------------------------------===//

using UnresolvedOperand = OpAsmParser::UnresolvedOperand;
using Argument = OpAsmParser::Argument;

struct DeferredLocInfo {
  SMLoc loc;
  StringRef identifier;
};

/// Push a new SSA name scope to the parser.
void pushSSANameScope(bool isIsolated);

/// Pop the last SSA name scope from the parser.
ParseResult popSSANameScope();

/// Register a definition of a value with the symbol table.
ParseResult addDefinition(UnresolvedOperand useInfo, Value value);

/// Parse an optional list of SSA uses into 'results'.
ParseResult
parseOptionalSSAUseList(SmallVectorImpl<UnresolvedOperand> &results);

/// Parse a single SSA use into 'result'.  If 'allowResultNumber' is true then
/// we allow #42 syntax.
ParseResult parseSSAUse(UnresolvedOperand &result,
                        bool allowResultNumber = true);

/// Given a reference to an SSA value and its type, return a reference. This
/// returns null on failure.
Value resolveSSAUse(UnresolvedOperand useInfo, Type type);

ParseResult parseSSADefOrUseAndType(
    function_ref<ParseResult(UnresolvedOperand, Type)> action);

ParseResult parseOptionalSSAUseAndTypeList(SmallVectorImpl<Value> &results);

/// Return the location of the value identified by its name and number if it
/// has been already reference.
std::optional<SMLoc> getReferenceLoc(StringRef name, unsigned number) {
  auto &values = isolatedNameScopes.back().values;
  if (!values.count(name) || number >= values[name].size())
    return {};
  if (values[name][number].value)
    return values[name][number].loc;
  return {};
}

//===--------------------------------------------------------------------===//
// Operation Parsing
//===--------------------------------------------------------------------===//

/// Parse an operation instance.
ParseResult parseOperation();

/// Parse a single operation successor.
ParseResult parseSuccessor(Block *&dest);

/// Parse a comma-separated list of operation successors in brackets.
ParseResult parseSuccessors(SmallVectorImpl<Block *> &destinations);

/// Parse an operation instance that is in the generic form.
Operation *parseGenericOperation();

/// Parse different components, viz., use-info of operand(s), successor(s),
/// region(s), attribute(s) and function-type, of the generic form of an
/// operation instance and populate the input operation-state 'result' with
/// those components. If any of the components is explicitly provided, then
/// skip parsing that component.
ParseResult parseGenericOperationAfterOpName(
    OperationState &result,
    std::optional<ArrayRef<UnresolvedOperand>> parsedOperandUseInfo =
        std::nullopt,
    std::optional<ArrayRef<Block *>> parsedSuccessors = std::nullopt,
    std::optional<MutableArrayRef<std::unique_ptr<Region>>> parsedRegions =
        std::nullopt,
    std::optional<ArrayRef<NamedAttribute>> parsedAttributes = std::nullopt,
    std::optional<Attribute> propertiesAttribute = std::nullopt,
    std::optional<FunctionType> parsedFnType = std::nullopt);

/// Parse an operation instance that is in the generic form and insert it at
/// the provided insertion point.
Operation *parseGenericOperation(Block *insertBlock,
                                 Block::iterator insertPt);

/// This type is used to keep track of things that are either an Operation or
/// a BlockArgument.  We cannot use Value for this, because not all Operations
/// have results.
using OpOrArgument = llvm::PointerUnion<Operation *, BlockArgument>;

/// Parse an optional trailing location and add it to the specifier Operation
/// or `UnresolvedOperand` if present.
///
///   trailing-location ::= (`loc` (`(` location `)` | attribute-alias))?
///
ParseResult parseTrailingLocationSpecifier(OpOrArgument opOrArgument);

/// Parse a location alias, that is a sequence looking like: #loc42
/// The alias may have already be defined or may be defined later, in which
/// case an OpaqueLoc is used a placeholder.
ParseResult parseLocationAlias(LocationAttr &loc);

/// This is the structure of a result specifier in the assembly syntax,
/// including the name, number of results, and location.
using ResultRecord = std::tuple<StringRef, unsigned, SMLoc>;

/// Parse an operation instance that is in the op-defined custom form.
/// resultInfo specifies information about the "%name =" specifiers.
Operation *parseCustomOperation(ArrayRef<ResultRecord> resultIDs);

/// Parse the name of an operation, in the custom form. On success, return a
/// an object of type 'OperationName'. Otherwise, failure is returned.
FailureOr<OperationName> parseCustomOperationName();

//===--------------------------------------------------------------------===//
// Region Parsing
//===--------------------------------------------------------------------===//

/// Parse a region into 'region' with the provided entry block arguments.
/// 'isIsolatedNameScope' indicates if the naming scope of this region is
/// isolated from those above.
ParseResult parseRegion(Region &region, ArrayRef<Argument> entryArguments,
                        bool isIsolatedNameScope = false);

/// Parse a region body into 'region'.
ParseResult parseRegionBody(Region &region, SMLoc startLoc,
                            ArrayRef<Argument> entryArguments,
                            bool isIsolatedNameScope);

//===--------------------------------------------------------------------===//
// Block Parsing
//===--------------------------------------------------------------------===//

/// Parse a new block into 'block'.
ParseResult parseBlock(Block *&block);

/// Parse a list of operations into 'block'.
ParseResult parseBlockBody(Block *block);

/// Parse a (possibly empty) list of block arguments.
ParseResult parseOptionalBlockArgList(Block *owner);

/// Get the block with the specified name, creating it if it doesn't
/// already exist.  The location specified is the point of use, which allows
/// us to diagnose references to blocks that are not defined precisely.
Block *getBlockNamed(StringRef name, SMLoc loc);

//===--------------------------------------------------------------------===//
// Code Completion
//===--------------------------------------------------------------------===//

/// The set of various code completion methods. Every completion method
/// returns `failure` to stop the parsing process after providing completion
/// results.

ParseResult codeCompleteSSAUse();
ParseResult codeCompleteBlock();

624private:
/// This class represents a definition of a Block.
struct BlockDefinition {
  /// A pointer to the defined Block.
  Block *block;
  /// The location that the Block was defined at.
  SMLoc loc;
};
/// This class represents a definition of a Value.
struct ValueDefinition {
  /// A pointer to the defined Value.
  Value value;
  /// The location that the Value was defined at.
  SMLoc loc;
};

/// Returns the info for a block at the current scope for the given name.
BlockDefinition &getBlockInfoByName(StringRef name) {
  return blocksByName.back()[name];
}

/// Insert a new forward reference to the given block.
void insertForwardRef(Block *block, SMLoc loc) {
  forwardRef.back().try_emplace(block, loc);
}

/// Erase any forward reference to the given block.
bool eraseForwardRef(Block *block) { return forwardRef.back().erase(block); }

/// Record that a definition was added at the current scope.
void recordDefinition(StringRef def);

/// Get the value entry for the given SSA name.
SmallVectorImpl<ValueDefinition> &getSSAValueEntry(StringRef name);

/// Create a forward reference placeholder value with the given location and
/// result type.
Value createForwardRefPlaceholder(SMLoc loc, Type type);

/// Return true if this is a forward reference.
bool isForwardRefPlaceholder(Value value) {
  return forwardRefPlaceholders.count(value);
}

/// This struct represents an isolated SSA name scope. This scope may contain
/// other nested non-isolated scopes. These scopes are used for operations
/// that are known to be isolated to allow for reusing names within their
/// regions, even if those names are used above.
struct IsolatedSSANameScope {
  /// Record that a definition was added at the current scope.
  void recordDefinition(StringRef def) {
    definitionsPerScope.back().insert(def);
  }

  /// Push a nested name scope.
  void pushSSANameScope() { definitionsPerScope.push_back({}); }

  /// Pop a nested name scope.
  void popSSANameScope() {
    for (auto &def : definitionsPerScope.pop_back_val())
      values.erase(def.getKey());
  }

  /// This keeps track of all of the SSA values we are tracking for each name
  /// scope, indexed by their name. This has one entry per result number.
  llvm::StringMap<SmallVector<ValueDefinition, 1>> values;

  /// This keeps track of all of the values defined by a specific name scope.
  SmallVector<llvm::StringSet<>, 2> definitionsPerScope;
};

/// A list of isolated name scopes.
SmallVector<IsolatedSSANameScope, 2> isolatedNameScopes;

/// This keeps track of the block names as well as the location of the first
/// reference for each nested name scope. This is used to diagnose invalid
/// block references and memorize them.
SmallVector<DenseMap<StringRef, BlockDefinition>, 2> blocksByName;
SmallVector<DenseMap<Block *, SMLoc>, 2> forwardRef;

/// These are all of the placeholders we've made along with the location of
/// their first reference, to allow checking for use of undefined values.
DenseMap<Value, SMLoc> forwardRefPlaceholders;

/// Deffered locations: when parsing `loc(#loc42)` we add an entry to this
/// map. After parsing the definition `#loc42 = ...` we'll patch back users
/// of this location.
std::vector<DeferredLocInfo> deferredLocsReferences;

/// The builder used when creating parsed operation instances.
OpBuilder opBuilder;

/// The top level operation that holds all of the parsed operations.
Operation *topLevelOp;
718};
719} // namespace

721MLIR_DECLARE_EXPLICIT_TYPE_ID(OperationParser::DeferredLocInfo *)namespace mlir { namespace detail { template <> class TypeIDResolver
<OperationParser::DeferredLocInfo *> { public: static TypeID
 resolveTypeID() { return id; } private: static SelfOwningTypeID
 id; }; } }
722MLIR_DEFINE_EXPLICIT_TYPE_ID(OperationParser::DeferredLocInfo *)namespace mlir { namespace detail { SelfOwningTypeID TypeIDResolver
<OperationParser::DeferredLocInfo *>::id = {}; } }

724OperationParser::OperationParser(ParserState &state, ModuleOp topLevelOp)
  : Parser(state), opBuilder(topLevelOp.getRegion()), topLevelOp(topLevelOp) {
// The top level operation starts a new name scope.
pushSSANameScope(/*isIsolated=*/true);

// If we are populating the parser state, prepare it for parsing.
if (state.asmState)
  state.asmState->initialize(topLevelOp);
732}

734OperationParser::~OperationParser() {
for (auto &fwd : forwardRefPlaceholders) {
  // Drop all uses of undefined forward declared reference and destroy
  // defining operation.
  fwd.first.dropAllUses();
  fwd.first.getDefiningOp()->destroy();
}
for (const auto &scope : forwardRef) {
  for (const auto &fwd : scope) {
    // Delete all blocks that were created as forward references but never
    // included into a region.
    fwd.first->dropAllUses();
    delete fwd.first;
  }
}
749}

751/// After parsing is finished, this function must be called to see if there are
752/// any remaining issues.
753ParseResult OperationParser::finalize() {
// Check for any forward references that are left.  If we find any, error
// out.
if (!forwardRefPlaceholders.empty()) {
  SmallVector<const char *, 4> errors;
  // Iteration over the map isn't deterministic, so sort by source location.
  for (auto entry : forwardRefPlaceholders)
    errors.push_back(entry.second.getPointer());
  llvm::array_pod_sort(errors.begin(), errors.end());

  for (const char *entry : errors) {
    auto loc = SMLoc::getFromPointer(entry);
    emitError(loc, "use of undeclared SSA value name");
  }
  return failure();
}

// Resolve the locations of any deferred operations.
auto &attributeAliases = state.symbols.attributeAliasDefinitions;
auto locID = TypeID::get<DeferredLocInfo *>();
auto resolveLocation = [&, this](auto &opOrArgument) -> LogicalResult {
  auto fwdLoc = dyn_cast<OpaqueLoc>(opOrArgument.getLoc());
  if (!fwdLoc || fwdLoc.getUnderlyingTypeID() != locID)
    return success();
  auto locInfo = deferredLocsReferences[fwdLoc.getUnderlyingLocation()];
  Attribute attr = attributeAliases.lookup(locInfo.identifier);
  if (!attr)
    return this->emitError(locInfo.loc)
           << "operation location alias was never defined";
  auto locAttr = dyn_cast<LocationAttr>(attr);
  if (!locAttr)
    return this->emitError(locInfo.loc)
           << "expected location, but found '" << attr << "'";
  opOrArgument.setLoc(locAttr);
  return success();
};

auto walkRes = topLevelOp->walk([&](Operation *op) {
  if (failed(resolveLocation(*op)))
    return WalkResult::interrupt();
  for (Region &region : op->getRegions())
    for (Block &block : region.getBlocks())
      for (BlockArgument arg : block.getArguments())
        if (failed(resolveLocation(arg)))
          return WalkResult::interrupt();
  return WalkResult::advance();
});
if (walkRes.wasInterrupted())
  return failure();

// Pop the top level name scope.
if (failed(popSSANameScope()))
  return failure();

// Verify that the parsed operations are valid.
if (state.config.shouldVerifyAfterParse() && failed(verify(topLevelOp)))
  return failure();

// If we are populating the parser state, finalize the top-level operation.
if (state.asmState)
  state.asmState->finalize(topLevelOp);
return success();
815}

817//===----------------------------------------------------------------------===//
818// SSA Value Handling
819//===----------------------------------------------------------------------===//

821void OperationParser::pushSSANameScope(bool isIsolated) {
blocksByName.push_back(DenseMap<StringRef, BlockDefinition>());
forwardRef.push_back(DenseMap<Block *, SMLoc>());

// Push back a new name definition scope.
if (isIsolated)
  isolatedNameScopes.push_back({});
isolatedNameScopes.back().pushSSANameScope();
829}

831ParseResult OperationParser::popSSANameScope() {
auto forwardRefInCurrentScope = forwardRef.pop_back_val();

// Verify that all referenced blocks were defined.
if (!forwardRefInCurrentScope.empty()) {
  SmallVector<std::pair<const char *, Block *>, 4> errors;
  // Iteration over the map isn't deterministic, so sort by source location.
  for (auto entry : forwardRefInCurrentScope) {
    errors.push_back({entry.second.getPointer(), entry.first});
    // Add this block to the top-level region to allow for automatic cleanup.
    topLevelOp->getRegion(0).push_back(entry.first);
  }
  llvm::array_pod_sort(errors.begin(), errors.end());

  for (auto entry : errors) {
    auto loc = SMLoc::getFromPointer(entry.first);
    emitError(loc, "reference to an undefined block");
  }
  return failure();
}

// Pop the next nested namescope. If there is only one internal namescope,
// just pop the isolated scope.
auto &currentNameScope = isolatedNameScopes.back();
if (currentNameScope.definitionsPerScope.size() == 1)
  isolatedNameScopes.pop_back();
else
  currentNameScope.popSSANameScope();

blocksByName.pop_back();
return success();
862}

864/// Register a definition of a value with the symbol table.
865ParseResult OperationParser::addDefinition(UnresolvedOperand useInfo,
                                         Value value) {
auto &entries = getSSAValueEntry(useInfo.name);

// Make sure there is a slot for this value.
if (entries.size() <= useInfo.number)
  entries.resize(useInfo.number + 1);

// If we already have an entry for this, check to see if it was a definition
// or a forward reference.
if (auto existing = entries[useInfo.number].value) {
  if (!isForwardRefPlaceholder(existing)) {
    return emitError(useInfo.location)
        .append("redefinition of SSA value '", useInfo.name, "'")
        .attachNote(getEncodedSourceLocation(entries[useInfo.number].loc))
        .append("previously defined here");
  }

  if (existing.getType() != value.getType()) {
    return emitError(useInfo.location)
        .append("definition of SSA value '", useInfo.name, "#",
                useInfo.number, "' has type ", value.getType())
        .attachNote(getEncodedSourceLocation(entries[useInfo.number].loc))
        .append("previously used here with type ", existing.getType());
  }

  // If it was a forward reference, update everything that used it to use
  // the actual definition instead, delete the forward ref, and remove it
  // from our set of forward references we track.
  existing.replaceAllUsesWith(value);
  existing.getDefiningOp()->destroy();
  forwardRefPlaceholders.erase(existing);

  // If a definition of the value already exists, replace it in the assembly
  // state.
  if (state.asmState)
    state.asmState->refineDefinition(existing, value);
}

/// Record this definition for the current scope.
entries[useInfo.number] = {value, useInfo.location};
recordDefinition(useInfo.name);
return success();
908}

910/// Parse a (possibly empty) list of SSA operands.
911///
912///   ssa-use-list ::= ssa-use (`,` ssa-use)*
913///   ssa-use-list-opt ::= ssa-use-list?
914///
915ParseResult OperationParser::parseOptionalSSAUseList(
  SmallVectorImpl<UnresolvedOperand> &results) {
if (!getToken().isOrIsCodeCompletionFor(Token::percent_identifier))
  return success();
return parseCommaSeparatedList([&]() -> ParseResult {
  UnresolvedOperand result;
  if (parseSSAUse(result))
    return failure();
  results.push_back(result);
  return success();
});
926}

928/// Parse a SSA operand for an operation.
929///
930///   ssa-use ::= ssa-id
931///
932ParseResult OperationParser::parseSSAUse(UnresolvedOperand &result,
                                       bool allowResultNumber) {
if (getToken().isCodeCompletion())
  return codeCompleteSSAUse();

result.name = getTokenSpelling();
result.number = 0;
result.location = getToken().getLoc();
if (parseToken(Token::percent_identifier, "expected SSA operand"))
  return failure();

// If we have an attribute ID, it is a result number.
if (getToken().is(Token::hash_identifier)) {
  if (!allowResultNumber)
    return emitError("result number not allowed in argument list");

  if (auto value = getToken().getHashIdentifierNumber())
    result.number = *value;
  else
    return emitError("invalid SSA value result number");
  consumeToken(Token::hash_identifier);
}

return success();
956}

958/// Given an unbound reference to an SSA value and its type, return the value
959/// it specifies.  This returns null on failure.
960Value OperationParser::resolveSSAUse(UnresolvedOperand useInfo, Type type) {
auto &entries = getSSAValueEntry(useInfo.name);

// Functor used to record the use of the given value if the assembly state
// field is populated.
auto maybeRecordUse = [&](Value value) {
  if (state.asmState)
    state.asmState->addUses(value, useInfo.location);
  return value;
};

// If we have already seen a value of this name, return it.
if (useInfo.number < entries.size() && entries[useInfo.number].value) {
  Value result = entries[useInfo.number].value;
  // Check that the type matches the other uses.
  if (result.getType() == type)
    return maybeRecordUse(result);

  emitError(useInfo.location, "use of value '")
      .append(useInfo.name,
              "' expects different type than prior uses: ", type, " vs ",
              result.getType())
      .attachNote(getEncodedSourceLocation(entries[useInfo.number].loc))
      .append("prior use here");
  return nullptr;
}

// Make sure we have enough slots for this.
if (entries.size() <= useInfo.number)
  entries.resize(useInfo.number + 1);

// If the value has already been defined and this is an overly large result
// number, diagnose that.
if (entries[0].value && !isForwardRefPlaceholder(entries[0].value))
  return (emitError(useInfo.location, "reference to invalid result number"),
          nullptr);

// Otherwise, this is a forward reference.  Create a placeholder and remember
// that we did so.
Value result = createForwardRefPlaceholder(useInfo.location, type);
entries[useInfo.number] = {result, useInfo.location};
return maybeRecordUse(result);
1002}

1004/// Parse an SSA use with an associated type.
1005///
1006///   ssa-use-and-type ::= ssa-use `:` type
1007ParseResult OperationParser::parseSSADefOrUseAndType(
  function_ref<ParseResult(UnresolvedOperand, Type)> action) {
UnresolvedOperand useInfo;
if (parseSSAUse(useInfo) ||
    parseToken(Token::colon, "expected ':' and type for SSA operand"))
  return failure();

auto type = parseType();
if (!type)
  return failure();

return action(useInfo, type);
1019}

1021/// Parse a (possibly empty) list of SSA operands, followed by a colon, then
1022/// followed by a type list.
1023///
1024///   ssa-use-and-type-list
1025///     ::= ssa-use-list ':' type-list-no-parens
1026///
1027ParseResult OperationParser::parseOptionalSSAUseAndTypeList(
  SmallVectorImpl<Value> &results) {
SmallVector<UnresolvedOperand, 4> valueIDs;
if (parseOptionalSSAUseList(valueIDs))
  return failure();

// If there were no operands, then there is no colon or type lists.
if (valueIDs.empty())
  return success();

SmallVector<Type, 4> types;
if (parseToken(Token::colon, "expected ':' in operand list") ||
    parseTypeListNoParens(types))
  return failure();

if (valueIDs.size() != types.size())
  return emitError("expected ")
         << valueIDs.size() << " types to match operand list";

results.reserve(valueIDs.size());
for (unsigned i = 0, e = valueIDs.size(); i != e; ++i) {
  if (auto value = resolveSSAUse(valueIDs[i], types[i]))
    results.push_back(value);
  else
    return failure();
}

return success();
1055}

1057/// Record that a definition was added at the current scope.
1058void OperationParser::recordDefinition(StringRef def) {
isolatedNameScopes.back().recordDefinition(def);
1060}

1062/// Get the value entry for the given SSA name.
1063auto OperationParser::getSSAValueEntry(StringRef name)
  -> SmallVectorImpl<ValueDefinition> & {
return isolatedNameScopes.back().values[name];
1066}

1068/// Create and remember a new placeholder for a forward reference.
1069Value OperationParser::createForwardRefPlaceholder(SMLoc loc, Type type) {
// Forward references are always created as operations, because we just need
// something with a def/use chain.
//
// We create these placeholders as having an empty name, which we know
// cannot be created through normal user input, allowing us to distinguish
// them.
auto name = OperationName("builtin.unrealized_conversion_cast", getContext());
auto *op = Operation::create(
    getEncodedSourceLocation(loc), name, type, /*operands=*/{},
    /*attributes=*/std::nullopt, /*properties=*/nullptr, /*successors=*/{},
    /*numRegions=*/0);
forwardRefPlaceholders[op->getResult(0)] = loc;
return op->getResult(0);
1083}

1085//===----------------------------------------------------------------------===//
1086// Operation Parsing
1087//===----------------------------------------------------------------------===//

1089/// Parse an operation.
1090///
1091///  operation         ::= op-result-list?
1092///                        (generic-operation | custom-operation)
1093///                        trailing-location?
1094///  generic-operation ::= string-literal `(` ssa-use-list? `)`
1095///                        successor-list? (`(` region-list `)`)?
1096///                        attribute-dict? `:` function-type
1097///  custom-operation  ::= bare-id custom-operation-format
1098///  op-result-list    ::= op-result (`,` op-result)* `=`
1099///  op-result         ::= ssa-id (`:` integer-literal)
1100///
1101ParseResult OperationParser::parseOperation() {
auto loc = getToken().getLoc();
SmallVector<ResultRecord, 1> resultIDs;
size_t numExpectedResults = 0;
if (getToken().is(Token::percent_identifier)) {
  // Parse the group of result ids.
  auto parseNextResult = [&]() -> ParseResult {
    // Parse the next result id.
    Token nameTok = getToken();
    if (parseToken(Token::percent_identifier,
                   "expected valid ssa identifier"))
      return failure();

    // If the next token is a ':', we parse the expected result count.
    size_t expectedSubResults = 1;
    if (consumeIf(Token::colon)) {
      // Check that the next token is an integer.
      if (!getToken().is(Token::integer))
        return emitWrongTokenError("expected integer number of results");

      // Check that number of results is > 0.
      auto val = getToken().getUInt64IntegerValue();
      if (!val || *val < 1)
        return emitError(
            "expected named operation to have at least 1 result");
      consumeToken(Token::integer);
      expectedSubResults = *val;
    }

    resultIDs.emplace_back(nameTok.getSpelling(), expectedSubResults,
                           nameTok.getLoc());
    numExpectedResults += expectedSubResults;
    return success();
  };
  if (parseCommaSeparatedList(parseNextResult))
    return failure();

  if (parseToken(Token::equal, "expected '=' after SSA name"))
    return failure();
}

Operation *op;
Token nameTok = getToken();
if (nameTok.is(Token::bare_identifier) || nameTok.isKeyword())
  op = parseCustomOperation(resultIDs);
else if (nameTok.is(Token::string))
  op = parseGenericOperation();
else if (nameTok.isCodeCompletionFor(Token::string))
  return codeCompleteStringDialectOrOperationName(nameTok.getStringValue());
else if (nameTok.isCodeCompletion())
  return codeCompleteDialectOrElidedOpName(loc);
else
  return emitWrongTokenError("expected operation name in quotes");

// If parsing of the basic operation failed, then this whole thing fails.
if (!op)
  return failure();

// If the operation had a name, register it.
if (!resultIDs.empty()) {
  if (op->getNumResults() == 0)
    return emitError(loc, "cannot name an operation with no results");
  if (numExpectedResults != op->getNumResults())
    return emitError(loc, "operation defines ")
           << op->getNumResults() << " results but was provided "
           << numExpectedResults << " to bind";

  // Add this operation to the assembly state if it was provided to populate.
  if (state.asmState) {
    unsigned resultIt = 0;
    SmallVector<std::pair<unsigned, SMLoc>> asmResultGroups;
    asmResultGroups.reserve(resultIDs.size());
    for (ResultRecord &record : resultIDs) {
      asmResultGroups.emplace_back(resultIt, std::get<2>(record));
      resultIt += std::get<1>(record);
    }
    state.asmState->finalizeOperationDefinition(
        op, nameTok.getLocRange(), /*endLoc=*/getToken().getLoc(),
        asmResultGroups);
  }

  // Add definitions for each of the result groups.
  unsigned opResI = 0;
  for (ResultRecord &resIt : resultIDs) {
    for (unsigned subRes : llvm::seq<unsigned>(0, std::get<1>(resIt))) {
      if (addDefinition({std::get<2>(resIt), std::get<0>(resIt), subRes},
                        op->getResult(opResI++)))
        return failure();
    }
  }

  // Add this operation to the assembly state if it was provided to populate.
} else if (state.asmState) {
  state.asmState->finalizeOperationDefinition(op, nameTok.getLocRange(),
                                              /*endLoc=*/getToken().getLoc());
}

return success();
1199}

1201/// Parse a single operation successor.
1202///
1203///   successor ::= block-id
1204///
1205ParseResult OperationParser::parseSuccessor(Block *&dest) {
if (getToken().isCodeCompletion())
3
←
Taking true branch→
  return codeCompleteBlock();
4
←
Returning without writing to 'dest'→

// Verify branch is identifier and get the matching block.
if (!getToken().is(Token::caret_identifier))
  return emitWrongTokenError("expected block name");
dest = getBlockNamed(getTokenSpelling(), getToken().getLoc());
consumeToken();
return success();
1215}

1217/// Parse a comma-separated list of operation successors in brackets.
1218///
1219///   successor-list ::= `[` successor (`,` successor )* `]`
1220///
1221ParseResult
1222OperationParser::parseSuccessors(SmallVectorImpl<Block *> &destinations) {
if (parseToken(Token::l_square, "expected '['"))
  return failure();

auto parseElt = [this, &destinations] {
  Block *dest;
1
'dest' declared without an initial value→
  ParseResult res = parseSuccessor(dest);
2
←
Calling 'OperationParser::parseSuccessor'→
5
←
Returning from 'OperationParser::parseSuccessor'→
  destinations.push_back(dest);
6
←
1st function call argument is an uninitialized value
  return res;
};
return parseCommaSeparatedListUntil(Token::r_square, parseElt,
                                    /*allowEmptyList=*/false);
1234}

1236namespace {
1237// RAII-style guard for cleaning up the regions in the operation state before
1238// deleting them.  Within the parser, regions may get deleted if parsing failed,
1239// and other errors may be present, in particular undominated uses.  This makes
1240// sure such uses are deleted.
1241struct CleanupOpStateRegions {
~CleanupOpStateRegions() {
  SmallVector<Region *, 4> regionsToClean;
  regionsToClean.reserve(state.regions.size());
  for (auto &region : state.regions)
    if (region)
      for (auto &block : *region)
        block.dropAllDefinedValueUses();
}
OperationState &state;
1251};
1252} // namespace

1254ParseResult OperationParser::parseGenericOperationAfterOpName(
  OperationState &result,
  std::optional<ArrayRef<UnresolvedOperand>> parsedOperandUseInfo,
  std::optional<ArrayRef<Block *>> parsedSuccessors,
  std::optional<MutableArrayRef<std::unique_ptr<Region>>> parsedRegions,
  std::optional<ArrayRef<NamedAttribute>> parsedAttributes,
  std::optional<Attribute> propertiesAttribute,
  std::optional<FunctionType> parsedFnType) {

// Parse the operand list, if not explicitly provided.
SmallVector<UnresolvedOperand, 8> opInfo;
if (!parsedOperandUseInfo) {
  if (parseToken(Token::l_paren, "expected '(' to start operand list") ||
      parseOptionalSSAUseList(opInfo) ||
      parseToken(Token::r_paren, "expected ')' to end operand list")) {
    return failure();
  }
  parsedOperandUseInfo = opInfo;
}

// Parse the successor list, if not explicitly provided.
if (!parsedSuccessors) {
  if (getToken().is(Token::l_square)) {
    // Check if the operation is not a known terminator.
    if (!result.name.mightHaveTrait<OpTrait::IsTerminator>())
      return emitError("successors in non-terminator");

    SmallVector<Block *, 2> successors;
    if (parseSuccessors(successors))
      return failure();
    result.addSuccessors(successors);
  }
} else {
  result.addSuccessors(*parsedSuccessors);
}

// Parse the properties, if not explicitly provided.
if (propertiesAttribute) {
  result.propertiesAttr = *propertiesAttribute;
} else if (consumeIf(Token::less)) {
  result.propertiesAttr = parseAttribute();
  if (!result.propertiesAttr)
    return failure();
  if (parseToken(Token::greater, "expected '>' to close properties"))
    return failure();
}
// Parse the region list, if not explicitly provided.
if (!parsedRegions) {
  if (consumeIf(Token::l_paren)) {
    do {
      // Create temporary regions with the top level region as parent.
      result.regions.emplace_back(new Region(topLevelOp));
      if (parseRegion(*result.regions.back(), /*entryArguments=*/{}))
        return failure();
    } while (consumeIf(Token::comma));
    if (parseToken(Token::r_paren, "expected ')' to end region list"))
      return failure();
  }
} else {
  result.addRegions(*parsedRegions);
}

// Parse the attributes, if not explicitly provided.
if (!parsedAttributes) {
  if (getToken().is(Token::l_brace)) {
    if (parseAttributeDict(result.attributes))
      return failure();
  }
} else {
  result.addAttributes(*parsedAttributes);
}

// Parse the operation type, if not explicitly provided.
Location typeLoc = result.location;
if (!parsedFnType) {
  if (parseToken(Token::colon, "expected ':' followed by operation type"))
    return failure();

  typeLoc = getEncodedSourceLocation(getToken().getLoc());
  auto type = parseType();
  if (!type)
    return failure();
  auto fnType = type.dyn_cast<FunctionType>();
  if (!fnType)
    return mlir::emitError(typeLoc, "expected function type");

  parsedFnType = fnType;
}

result.addTypes(parsedFnType->getResults());

// Check that we have the right number of types for the operands.
ArrayRef<Type> operandTypes = parsedFnType->getInputs();
if (operandTypes.size() != parsedOperandUseInfo->size()) {
  auto plural = "s"[parsedOperandUseInfo->size() == 1];
  return mlir::emitError(typeLoc, "expected ")
         << parsedOperandUseInfo->size() << " operand type" << plural
         << " but had " << operandTypes.size();
}

// Resolve all of the operands.
for (unsigned i = 0, e = parsedOperandUseInfo->size(); i != e; ++i) {
  result.operands.push_back(
      resolveSSAUse((*parsedOperandUseInfo)[i], operandTypes[i]));
  if (!result.operands.back())
    return failure();
}

return success();
1363}

1365Operation *OperationParser::parseGenericOperation() {
// Get location information for the operation.
auto srcLocation = getEncodedSourceLocation(getToken().getLoc());

std::string name = getToken().getStringValue();
if (name.empty())
  return (emitError("empty operation name is invalid"), nullptr);
if (name.find('\0') != StringRef::npos)
  return (emitError("null character not allowed in operation name"), nullptr);

consumeToken(Token::string);

OperationState result(srcLocation, name);
CleanupOpStateRegions guard{result};

// Lazy load dialects in the context as needed.
if (!result.name.isRegistered()) {
  StringRef dialectName = StringRef(name).split('.').first;
  if (!getContext()->getLoadedDialect(dialectName) &&
      !getContext()->getOrLoadDialect(dialectName)) {
    if (!getContext()->allowsUnregisteredDialects()) {
      // Emit an error if the dialect couldn't be loaded (i.e., it was not
      // registered) and unregistered dialects aren't allowed.
      emitError("operation being parsed with an unregistered dialect. If "
                "this is intended, please use -allow-unregistered-dialect "
                "with the MLIR tool used");
      return nullptr;
    }
  } else {
    // Reload the OperationName now that the dialect is loaded.
    result.name = OperationName(name, getContext());
  }
}

// If we are populating the parser state, start a new operation definition.
if (state.asmState)
  state.asmState->startOperationDefinition(result.name);

if (parseGenericOperationAfterOpName(result))
  return nullptr;

// Operation::create() is not allowed to fail, however setting the properties
// from an attribute is a failable operation. So we save the attribute here
// and set it on the operation post-parsing.
Attribute properties;
std::swap(properties, result.propertiesAttr);

// If we don't have properties in the textual IR, but the operation now has
// support for properties, we support some backward-compatible generic syntax
// for the operation and as such we accept inherent attributes mixed in the
// dictionary of discardable attributes. We pre-validate these here because
// invalid attributes can't be casted to the properties storage and will be
// silently dropped. For example an attribute { foo = 0 : i32 } that is
// declared as F32Attr in ODS would have a C++ type of FloatAttr in the
// properties array. When setting it we would do something like:
//
//   properties.foo = dyn_cast<FloatAttr>(fooAttr);
//
// which would end up with a null Attribute. The diagnostic from the verifier
// would be "missing foo attribute" instead of something like "expects a 32
// bits float attribute but got a 32 bits integer attribute".
if (!properties && !result.getRawProperties()) {
  std::optional<RegisteredOperationName> info =
      result.name.getRegisteredInfo();
  if (info) {
    if (failed(info->verifyInherentAttrs(result.attributes, [&]() {
          return mlir::emitError(srcLocation) << "'" << name << "' op ";
        })))
      return nullptr;
  }
}

// Create the operation and try to parse a location for it.
Operation *op = opBuilder.create(result);
if (parseTrailingLocationSpecifier(op))
  return nullptr;

// Try setting the properties for the operation, using a diagnostic to print
// errors.
if (properties) {
  InFlightDiagnostic diagnostic =
      mlir::emitError(srcLocation, "invalid properties ")
      << properties << " for op " << name << ": ";
  if (failed(op->setPropertiesFromAttribute(properties, &diagnostic)))
    return nullptr;
  diagnostic.abandon();
}

return op;
1454}

1456Operation *OperationParser::parseGenericOperation(Block *insertBlock,
                                                Block::iterator insertPt) {
Token nameToken = getToken();

OpBuilder::InsertionGuard restoreInsertionPoint(opBuilder);
opBuilder.setInsertionPoint(insertBlock, insertPt);
Operation *op = parseGenericOperation();
if (!op)
  return nullptr;

// If we are populating the parser asm state, finalize this operation
// definition.
if (state.asmState)
  state.asmState->finalizeOperationDefinition(op, nameToken.getLocRange(),
                                              /*endLoc=*/getToken().getLoc());
return op;
1472}

1474namespace {
1475class CustomOpAsmParser : public AsmParserImpl<OpAsmParser> {
1476public:
CustomOpAsmParser(
    SMLoc nameLoc, ArrayRef<OperationParser::ResultRecord> resultIDs,
    function_ref<ParseResult(OpAsmParser &, OperationState &)> parseAssembly,
    bool isIsolatedFromAbove, StringRef opName, OperationParser &parser)
    : AsmParserImpl<OpAsmParser>(nameLoc, parser), resultIDs(resultIDs),
      parseAssembly(parseAssembly), isIsolatedFromAbove(isIsolatedFromAbove),
      opName(opName), parser(parser) {
  (void)isIsolatedFromAbove; // Only used in assert, silence unused warning.
}

/// Parse an instance of the operation described by 'opDefinition' into the
/// provided operation state.
ParseResult parseOperation(OperationState &opState) {
  if (parseAssembly(*this, opState))
    return failure();
  // Verify that the parsed attributes does not have duplicate attributes.
  // This can happen if an attribute set during parsing is also specified in
  // the attribute dictionary in the assembly, or the attribute is set
  // multiple during parsing.
  std::optional<NamedAttribute> duplicate =
      opState.attributes.findDuplicate();
  if (duplicate)
    return emitError(getNameLoc(), "attribute '")
           << duplicate->getName().getValue()
           << "' occurs more than once in the attribute list";
  return success();
}

Operation *parseGenericOperation(Block *insertBlock,
                                 Block::iterator insertPt) final {
  return parser.parseGenericOperation(insertBlock, insertPt);
}

FailureOr<OperationName> parseCustomOperationName() final {
  return parser.parseCustomOperationName();
}

ParseResult parseGenericOperationAfterOpName(
    OperationState &result,
    std::optional<ArrayRef<UnresolvedOperand>> parsedUnresolvedOperands,
    std::optional<ArrayRef<Block *>> parsedSuccessors,
    std::optional<MutableArrayRef<std::unique_ptr<Region>>> parsedRegions,
    std::optional<ArrayRef<NamedAttribute>> parsedAttributes,
    std::optional<Attribute> parsedPropertiesAttribute,
    std::optional<FunctionType> parsedFnType) final {
  return parser.parseGenericOperationAfterOpName(
      result, parsedUnresolvedOperands, parsedSuccessors, parsedRegions,
      parsedAttributes, parsedPropertiesAttribute, parsedFnType);
}
//===--------------------------------------------------------------------===//
// Utilities
//===--------------------------------------------------------------------===//

/// Return the name of the specified result in the specified syntax, as well
/// as the subelement in the name.  For example, in this operation:
///
///  %x, %y:2, %z = foo.op
///
///    getResultName(0) == {"x", 0 }
///    getResultName(1) == {"y", 0 }
///    getResultName(2) == {"y", 1 }
///    getResultName(3) == {"z", 0 }
std::pair<StringRef, unsigned>
getResultName(unsigned resultNo) const override {
  // Scan for the resultID that contains this result number.
  for (const auto &entry : resultIDs) {
    if (resultNo < std::get<1>(entry)) {
      // Don't pass on the leading %.
      StringRef name = std::get<0>(entry).drop_front();
      return {name, resultNo};
    }
    resultNo -= std::get<1>(entry);
  }

  // Invalid result number.
  return {"", ~0U};
}

/// Return the number of declared SSA results.  This returns 4 for the foo.op
/// example in the comment for getResultName.
size_t getNumResults() const override {
  size_t count = 0;
  for (auto &entry : resultIDs)
    count += std::get<1>(entry);
  return count;
}

/// Emit a diagnostic at the specified location and return failure.
InFlightDiagnostic emitError(SMLoc loc, const Twine &message) override {
  return AsmParserImpl<OpAsmParser>::emitError(loc, "custom op '" + opName +
                                                        "' " + message);
}

//===--------------------------------------------------------------------===//
// Operand Parsing
//===--------------------------------------------------------------------===//

/// Parse a single operand.
ParseResult parseOperand(UnresolvedOperand &result,
                         bool allowResultNumber = true) override {
  OperationParser::UnresolvedOperand useInfo;
  if (parser.parseSSAUse(useInfo, allowResultNumber))
    return failure();

  result = {useInfo.location, useInfo.name, useInfo.number};
  return success();
}

/// Parse a single operand if present.
OptionalParseResult
parseOptionalOperand(UnresolvedOperand &result,
                     bool allowResultNumber = true) override {
  if (parser.getToken().isOrIsCodeCompletionFor(Token::percent_identifier))
    return parseOperand(result, allowResultNumber);
  return std::nullopt;
}

/// Parse zero or more SSA comma-separated operand references with a specified
/// surrounding delimiter, and an optional required operand count.
ParseResult parseOperandList(SmallVectorImpl<UnresolvedOperand> &result,
                             Delimiter delimiter = Delimiter::None,
                             bool allowResultNumber = true,
                             int requiredOperandCount = -1) override {
  // The no-delimiter case has some special handling for better diagnostics.
  if (delimiter == Delimiter::None) {
    // parseCommaSeparatedList doesn't handle the missing case for "none",
    // so we handle it custom here.
    Token tok = parser.getToken();
    if (!tok.isOrIsCodeCompletionFor(Token::percent_identifier)) {
      // If we didn't require any operands or required exactly zero (weird)
      // then this is success.
      if (requiredOperandCount == -1 || requiredOperandCount == 0)
        return success();

      // Otherwise, try to produce a nice error message.
      if (tok.isAny(Token::l_paren, Token::l_square))
        return parser.emitError("unexpected delimiter");
      return parser.emitWrongTokenError("expected operand");
    }
  }

  auto parseOneOperand = [&]() -> ParseResult {
    return parseOperand(result.emplace_back(), allowResultNumber);
  };

  auto startLoc = parser.getToken().getLoc();
  if (parseCommaSeparatedList(delimiter, parseOneOperand, " in operand list"))
    return failure();

  // Check that we got the expected # of elements.
  if (requiredOperandCount != -1 &&
      result.size() != static_cast<size_t>(requiredOperandCount))
    return emitError(startLoc, "expected ")
           << requiredOperandCount << " operands";
  return success();
}

/// Resolve an operand to an SSA value, emitting an error on failure.
ParseResult resolveOperand(const UnresolvedOperand &operand, Type type,
                           SmallVectorImpl<Value> &result) override {
  if (auto value = parser.resolveSSAUse(operand, type)) {
    result.push_back(value);
    return success();
  }
  return failure();
}

/// Parse an AffineMap of SSA ids.
ParseResult
parseAffineMapOfSSAIds(SmallVectorImpl<UnresolvedOperand> &operands,
                       Attribute &mapAttr, StringRef attrName,
                       NamedAttrList &attrs, Delimiter delimiter) override {
  SmallVector<UnresolvedOperand, 2> dimOperands;
  SmallVector<UnresolvedOperand, 1> symOperands;

  auto parseElement = [&](bool isSymbol) -> ParseResult {
    UnresolvedOperand operand;
    if (parseOperand(operand))
      return failure();
    if (isSymbol)
      symOperands.push_back(operand);
    else
      dimOperands.push_back(operand);
    return success();
  };

  AffineMap map;
  if (parser.parseAffineMapOfSSAIds(map, parseElement, delimiter))
    return failure();
  // Add AffineMap attribute.
  if (map) {
    mapAttr = AffineMapAttr::get(map);
    attrs.push_back(parser.builder.getNamedAttr(attrName, mapAttr));
  }

  // Add dim operands before symbol operands in 'operands'.
  operands.assign(dimOperands.begin(), dimOperands.end());
  operands.append(symOperands.begin(), symOperands.end());
  return success();
}

/// Parse an AffineExpr of SSA ids.
ParseResult
parseAffineExprOfSSAIds(SmallVectorImpl<UnresolvedOperand> &dimOperands,
                        SmallVectorImpl<UnresolvedOperand> &symbOperands,
                        AffineExpr &expr) override {
  auto parseElement = [&](bool isSymbol) -> ParseResult {
    UnresolvedOperand operand;
    if (parseOperand(operand))
      return failure();
    if (isSymbol)
      symbOperands.push_back(operand);
    else
      dimOperands.push_back(operand);
    return success();
  };

  return parser.parseAffineExprOfSSAIds(expr, parseElement);
}

//===--------------------------------------------------------------------===//
// Argument Parsing
//===--------------------------------------------------------------------===//

/// Parse a single argument with the following syntax:
///
///   `%ssaname : !type { optionalAttrDict} loc(optionalSourceLoc)`
///
/// If `allowType` is false or `allowAttrs` are false then the respective
/// parts of the grammar are not parsed.
ParseResult parseArgument(Argument &result, bool allowType = false,
                          bool allowAttrs = false) override {
  NamedAttrList attrs;
  if (parseOperand(result.ssaName, /*allowResultNumber=*/false) ||
      (allowType && parseColonType(result.type)) ||
      (allowAttrs && parseOptionalAttrDict(attrs)) ||
      parseOptionalLocationSpecifier(result.sourceLoc))
    return failure();
  result.attrs = attrs.getDictionary(getContext());
  return success();
}

/// Parse a single argument if present.
OptionalParseResult parseOptionalArgument(Argument &result, bool allowType,
                                          bool allowAttrs) override {
  if (parser.getToken().is(Token::percent_identifier))
    return parseArgument(result, allowType, allowAttrs);
  return std::nullopt;
}

ParseResult parseArgumentList(SmallVectorImpl<Argument> &result,
                              Delimiter delimiter, bool allowType,
                              bool allowAttrs) override {
  // The no-delimiter case has some special handling for the empty case.
  if (delimiter == Delimiter::None &&
      parser.getToken().isNot(Token::percent_identifier))
    return success();

  auto parseOneArgument = [&]() -> ParseResult {
    return parseArgument(result.emplace_back(), allowType, allowAttrs);
  };
  return parseCommaSeparatedList(delimiter, parseOneArgument,
                                 " in argument list");
}

//===--------------------------------------------------------------------===//
// Region Parsing
//===--------------------------------------------------------------------===//

/// Parse a region that takes `arguments` of `argTypes` types.  This
/// effectively defines the SSA values of `arguments` and assigns their type.
ParseResult parseRegion(Region &region, ArrayRef<Argument> arguments,
                        bool enableNameShadowing) override {
  // Try to parse the region.
  (void)isIsolatedFromAbove;
  assert((!enableNameShadowing || isIsolatedFromAbove) &&(static_cast <bool> ((!enableNameShadowing || isIsolatedFromAbove
) && "name shadowing is only allowed on isolated regions"
) ? void (0) : __assert_fail ("(!enableNameShadowing || isIsolatedFromAbove) && \"name shadowing is only allowed on isolated regions\""
, "mlir/lib/AsmParser/Parser.cpp", 1753, __extension__ __PRETTY_FUNCTION__
))
         "name shadowing is only allowed on isolated regions")(static_cast <bool> ((!enableNameShadowing || isIsolatedFromAbove
) && "name shadowing is only allowed on isolated regions"
) ? void (0) : __assert_fail ("(!enableNameShadowing || isIsolatedFromAbove) && \"name shadowing is only allowed on isolated regions\""
, "mlir/lib/AsmParser/Parser.cpp", 1753, __extension__ __PRETTY_FUNCTION__
));
  if (parser.parseRegion(region, arguments, enableNameShadowing))
    return failure();
  return success();
}

/// Parses a region if present.
OptionalParseResult parseOptionalRegion(Region &region,
                                        ArrayRef<Argument> arguments,
                                        bool enableNameShadowing) override {
  if (parser.getToken().isNot(Token::l_brace))
    return std::nullopt;
  return parseRegion(region, arguments, enableNameShadowing);
}

/// Parses a region if present. If the region is present, a new region is
/// allocated and placed in `region`. If no region is present, `region`
/// remains untouched.
OptionalParseResult
parseOptionalRegion(std::unique_ptr<Region> &region,
                    ArrayRef<Argument> arguments,
                    bool enableNameShadowing = false) override {
  if (parser.getToken().isNot(Token::l_brace))
    return std::nullopt;
  std::unique_ptr<Region> newRegion = std::make_unique<Region>();
  if (parseRegion(*newRegion, arguments, enableNameShadowing))
    return failure();

  region = std::move(newRegion);
  return success();
}

//===--------------------------------------------------------------------===//
// Successor Parsing
//===--------------------------------------------------------------------===//

/// Parse a single operation successor.
ParseResult parseSuccessor(Block *&dest) override {
  return parser.parseSuccessor(dest);
}

/// Parse an optional operation successor and its operand list.
OptionalParseResult parseOptionalSuccessor(Block *&dest) override {
  if (!parser.getToken().isOrIsCodeCompletionFor(Token::caret_identifier))
    return std::nullopt;
  return parseSuccessor(dest);
}

/// Parse a single operation successor and its operand list.
ParseResult
parseSuccessorAndUseList(Block *&dest,
                         SmallVectorImpl<Value> &operands) override {
  if (parseSuccessor(dest))
    return failure();

  // Handle optional arguments.
  if (succeeded(parseOptionalLParen()) &&
      (parser.parseOptionalSSAUseAndTypeList(operands) || parseRParen())) {
    return failure();
  }
  return success();
}

//===--------------------------------------------------------------------===//
// Type Parsing
//===--------------------------------------------------------------------===//

/// Parse a list of assignments of the form
///   (%x1 = %y1, %x2 = %y2, ...).
OptionalParseResult parseOptionalAssignmentList(
    SmallVectorImpl<Argument> &lhs,
    SmallVectorImpl<UnresolvedOperand> &rhs) override {
  if (failed(parseOptionalLParen()))
    return std::nullopt;

  auto parseElt = [&]() -> ParseResult {
    if (parseArgument(lhs.emplace_back()) || parseEqual() ||
        parseOperand(rhs.emplace_back()))
      return failure();
    return success();
  };
  return parser.parseCommaSeparatedListUntil(Token::r_paren, parseElt);
}

/// Parse a loc(...) specifier if present, filling in result if so.
ParseResult
parseOptionalLocationSpecifier(std::optional<Location> &result) override {
  // If there is a 'loc' we parse a trailing location.
  if (!parser.consumeIf(Token::kw_loc))
    return success();
  LocationAttr directLoc;
  if (parser.parseToken(Token::l_paren, "expected '(' in location"))
    return failure();

  Token tok = parser.getToken();

  // Check to see if we are parsing a location alias.
  // Otherwise, we parse the location directly.
  if (tok.is(Token::hash_identifier)) {
    if (parser.parseLocationAlias(directLoc))
      return failure();
  } else if (parser.parseLocationInstance(directLoc)) {
    return failure();
  }

  if (parser.parseToken(Token::r_paren, "expected ')' in location"))
    return failure();

  result = directLoc;
  return success();
}

1865private:
/// Information about the result name specifiers.
ArrayRef<OperationParser::ResultRecord> resultIDs;

/// The abstract information of the operation.
function_ref<ParseResult(OpAsmParser &, OperationState &)> parseAssembly;
bool isIsolatedFromAbove;
StringRef opName;

/// The backing operation parser.
OperationParser &parser;
1876};
1877} // namespace

1879FailureOr<OperationName> OperationParser::parseCustomOperationName() {
Token nameTok = getToken();
StringRef opName = nameTok.getSpelling();
if (opName.empty())
  return (emitError("empty operation name is invalid"), failure());
consumeToken();

// Check to see if this operation name is already registered.
std::optional<RegisteredOperationName> opInfo =
    RegisteredOperationName::lookup(opName, getContext());
if (opInfo)
  return *opInfo;

// If the operation doesn't have a dialect prefix try using the default
// dialect.
auto opNameSplit = opName.split('.');
StringRef dialectName = opNameSplit.first;
std::string opNameStorage;
if (opNameSplit.second.empty()) {
  // If the name didn't have a prefix, check for a code completion request.
  if (getToken().isCodeCompletion() && opName.back() == '.')
    return codeCompleteOperationName(dialectName);

  dialectName = getState().defaultDialectStack.back();
  opNameStorage = (dialectName + "." + opName).str();
  opName = opNameStorage;
}

// Try to load the dialect before returning the operation name to make sure
// the operation has a chance to be registered.
getContext()->getOrLoadDialect(dialectName);
return OperationName(opName, getContext());
1911}

1913Operation *
1914OperationParser::parseCustomOperation(ArrayRef<ResultRecord> resultIDs) {
SMLoc opLoc = getToken().getLoc();
StringRef originalOpName = getTokenSpelling();

FailureOr<OperationName> opNameInfo = parseCustomOperationName();
if (failed(opNameInfo))
  return nullptr;
StringRef opName = opNameInfo->getStringRef();

// This is the actual hook for the custom op parsing, usually implemented by
// the op itself (`Op::parse()`). We retrieve it either from the
// RegisteredOperationName or from the Dialect.
OperationName::ParseAssemblyFn parseAssemblyFn;
bool isIsolatedFromAbove = false;

StringRef defaultDialect = "";
if (auto opInfo = opNameInfo->getRegisteredInfo()) {
  parseAssemblyFn = opInfo->getParseAssemblyFn();
  isIsolatedFromAbove = opInfo->hasTrait<OpTrait::IsIsolatedFromAbove>();
  auto *iface = opInfo->getInterface<OpAsmOpInterface>();
  if (iface && !iface->getDefaultDialect().empty())
    defaultDialect = iface->getDefaultDialect();
} else {
  std::optional<Dialect::ParseOpHook> dialectHook;
  Dialect *dialect = opNameInfo->getDialect();
  if (!dialect) {
    InFlightDiagnostic diag =
        emitError(opLoc) << "Dialect `" << opNameInfo->getDialectNamespace()
                         << "' not found for custom op '" << originalOpName
                         << "' ";
    if (originalOpName != opName)
      diag << " (tried '" << opName << "' as well)";
    auto &note = diag.attachNote();
    note << "Registered dialects: ";
    llvm::interleaveComma(getContext()->getAvailableDialects(), note,
                          [&](StringRef dialect) { note << dialect; });
    note << " ; for more info on dialect registration see "
            "https://mlir.llvm.org/getting_started/Faq/"
            "#registered-loaded-dependent-whats-up-with-dialects-management";
    return nullptr;
  }
  dialectHook = dialect->getParseOperationHook(opName);
  if (!dialectHook) {
    InFlightDiagnostic diag =
        emitError(opLoc) << "custom op '" << originalOpName << "' is unknown";
    if (originalOpName != opName)
      diag << " (tried '" << opName << "' as well)";
    return nullptr;
  }
  parseAssemblyFn = *dialectHook;
}
getState().defaultDialectStack.push_back(defaultDialect);
auto restoreDefaultDialect = llvm::make_scope_exit(
    [&]() { getState().defaultDialectStack.pop_back(); });

// If the custom op parser crashes, produce some indication to help
// debugging.
llvm::PrettyStackTraceFormat fmt("MLIR Parser: custom op parser '%s'",
                                 opNameInfo->getIdentifier().data());

// Get location information for the operation.
auto srcLocation = getEncodedSourceLocation(opLoc);
OperationState opState(srcLocation, *opNameInfo);

// If we are populating the parser state, start a new operation definition.
if (state.asmState)
  state.asmState->startOperationDefinition(opState.name);

// Have the op implementation take a crack and parsing this.
CleanupOpStateRegions guard{opState};
CustomOpAsmParser opAsmParser(opLoc, resultIDs, parseAssemblyFn,
                              isIsolatedFromAbove, opName, *this);
if (opAsmParser.parseOperation(opState))
  return nullptr;

// If it emitted an error, we failed.
if (opAsmParser.didEmitError())
  return nullptr;

Attribute properties = opState.propertiesAttr;
opState.propertiesAttr = Attribute{};

// Otherwise, create the operation and try to parse a location for it.
Operation *op = opBuilder.create(opState);
if (parseTrailingLocationSpecifier(op))
  return nullptr;

// Try setting the properties for the operation.
if (properties) {
  InFlightDiagnostic diagnostic =
      mlir::emitError(srcLocation, "invalid properties ")
      << properties << " for op " << op->getName().getStringRef() << ": ";
  if (failed(op->setPropertiesFromAttribute(properties, &diagnostic)))
    return nullptr;
  diagnostic.abandon();
}
return op;
2011}

2013ParseResult OperationParser::parseLocationAlias(LocationAttr &loc) {
Token tok = getToken();
consumeToken(Token::hash_identifier);
StringRef identifier = tok.getSpelling().drop_front();
if (identifier.contains('.')) {
  return emitError(tok.getLoc())
         << "expected location, but found dialect attribute: '#" << identifier
         << "'";
}

// If this alias can be resolved, do it now.
Attribute attr = state.symbols.attributeAliasDefinitions.lookup(identifier);
if (attr) {
  if (!(loc = dyn_cast<LocationAttr>(attr)))
    return emitError(tok.getLoc())
           << "expected location, but found '" << attr << "'";
} else {
  // Otherwise, remember this operation and resolve its location later.
  // In the meantime, use a special OpaqueLoc as a marker.
  loc = OpaqueLoc::get(deferredLocsReferences.size(),
                       TypeID::get<DeferredLocInfo *>(),
                       UnknownLoc::get(getContext()));
  deferredLocsReferences.push_back(DeferredLocInfo{tok.getLoc(), identifier});
}
return success();
2038}

2040ParseResult
2041OperationParser::parseTrailingLocationSpecifier(OpOrArgument opOrArgument) {
// If there is a 'loc' we parse a trailing location.
if (!consumeIf(Token::kw_loc))
  return success();
if (parseToken(Token::l_paren, "expected '(' in location"))
  return failure();
Token tok = getToken();

// Check to see if we are parsing a location alias.
// Otherwise, we parse the location directly.
LocationAttr directLoc;
if (tok.is(Token::hash_identifier)) {
  if (parseLocationAlias(directLoc))
    return failure();
} else if (parseLocationInstance(directLoc)) {
  return failure();
}

if (parseToken(Token::r_paren, "expected ')' in location"))
  return failure();

if (auto *op = opOrArgument.dyn_cast<Operation *>())
  op->setLoc(directLoc);
else
  opOrArgument.get<BlockArgument>().setLoc(directLoc);
return success();
2067}

2069//===----------------------------------------------------------------------===//
2070// Region Parsing
2071//===----------------------------------------------------------------------===//

2073ParseResult OperationParser::parseRegion(Region &region,
                                       ArrayRef<Argument> entryArguments,
                                       bool isIsolatedNameScope) {
// Parse the '{'.
Token lBraceTok = getToken();
if (parseToken(Token::l_brace, "expected '{' to begin a region"))
  return failure();

// If we are populating the parser state, start a new region definition.
if (state.asmState)
  state.asmState->startRegionDefinition();

// Parse the region body.
if ((!entryArguments.empty() || getToken().isNot(Token::r_brace)) &&
    parseRegionBody(region, lBraceTok.getLoc(), entryArguments,
                    isIsolatedNameScope)) {
  return failure();
}
consumeToken(Token::r_brace);

// If we are populating the parser state, finalize this region.
if (state.asmState)
  state.asmState->finalizeRegionDefinition();

return success();
2098}

2100ParseResult OperationParser::parseRegionBody(Region &region, SMLoc startLoc,
                                           ArrayRef<Argument> entryArguments,
                                           bool isIsolatedNameScope) {
auto currentPt = opBuilder.saveInsertionPoint();

// Push a new named value scope.
pushSSANameScope(isIsolatedNameScope);

// Parse the first block directly to allow for it to be unnamed.
auto owningBlock = std::make_unique<Block>();
Block *block = owningBlock.get();

// If this block is not defined in the source file, add a definition for it
// now in the assembly state. Blocks with a name will be defined when the name
// is parsed.
if (state.asmState && getToken().isNot(Token::caret_identifier))
  state.asmState->addDefinition(block, startLoc);

// Add arguments to the entry block if we had the form with explicit names.
if (!entryArguments.empty() && !entryArguments[0].ssaName.name.empty()) {
  // If we had named arguments, then don't allow a block name.
  if (getToken().is(Token::caret_identifier))
    return emitError("invalid block name in region with named arguments");

  for (auto &entryArg : entryArguments) {
    auto &argInfo = entryArg.ssaName;

    // Ensure that the argument was not already defined.
    if (auto defLoc = getReferenceLoc(argInfo.name, argInfo.number)) {
      return emitError(argInfo.location, "region entry argument '" +
                                             argInfo.name +
                                             "' is already in use")
                 .attachNote(getEncodedSourceLocation(*defLoc))
             << "previously referenced here";
    }
    Location loc = entryArg.sourceLoc.has_value()
                       ? *entryArg.sourceLoc
                       : getEncodedSourceLocation(argInfo.location);
    BlockArgument arg = block->addArgument(entryArg.type, loc);

    // Add a definition of this arg to the assembly state if provided.
    if (state.asmState)
      state.asmState->addDefinition(arg, argInfo.location);

    // Record the definition for this argument.
    if (addDefinition(argInfo, arg))
      return failure();
  }
}

if (parseBlock(block))
  return failure();

// Verify that no other arguments were parsed.
if (!entryArguments.empty() &&
    block->getNumArguments() > entryArguments.size()) {
  return emitError("entry block arguments were already defined");
}

// Parse the rest of the region.
region.push_back(owningBlock.release());
while (getToken().isNot(Token::r_brace)) {
  Block *newBlock = nullptr;
  if (parseBlock(newBlock))
    return failure();
  region.push_back(newBlock);
}

// Pop the SSA value scope for this region.
if (popSSANameScope())
  return failure();

// Reset the original insertion point.
opBuilder.restoreInsertionPoint(currentPt);
return success();
2175}

2177//===----------------------------------------------------------------------===//
2178// Block Parsing
2179//===----------------------------------------------------------------------===//

2181/// Block declaration.
2182///
2183///   block ::= block-label? operation*
2184///   block-label    ::= block-id block-arg-list? `:`
2185///   block-id       ::= caret-id
2186///   block-arg-list ::= `(` ssa-id-and-type-list? `)`
2187///
2188ParseResult OperationParser::parseBlock(Block *&block) {
// The first block of a region may already exist, if it does the caret
// identifier is optional.
if (block && getToken().isNot(Token::caret_identifier))
  return parseBlockBody(block);

SMLoc nameLoc = getToken().getLoc();
auto name = getTokenSpelling();
if (parseToken(Token::caret_identifier, "expected block name"))
  return failure();

// Define the block with the specified name.
auto &blockAndLoc = getBlockInfoByName(name);
blockAndLoc.loc = nameLoc;

// Use a unique pointer for in-flight block being parsed. Release ownership
// only in the case of a successful parse. This ensures that the Block
// allocated is released if the parse fails and control returns early.
std::unique_ptr<Block> inflightBlock;
auto cleanupOnFailure = llvm::make_scope_exit([&] {
  if (inflightBlock)
    inflightBlock->dropAllDefinedValueUses();
});

// If a block has yet to be set, this is a new definition. If the caller
// provided a block, use it. Otherwise create a new one.
if (!blockAndLoc.block) {
  if (block) {
    blockAndLoc.block = block;
  } else {
    inflightBlock = std::make_unique<Block>();
    blockAndLoc.block = inflightBlock.get();
  }

  // Otherwise, the block has a forward declaration. Forward declarations are
  // removed once defined, so if we are defining a existing block and it is
  // not a forward declaration, then it is a redeclaration. Fail if the block
  // was already defined.
} else if (!eraseForwardRef(blockAndLoc.block)) {
  return emitError(nameLoc, "redefinition of block '") << name << "'";
} else {
  // This was a forward reference block that is now floating. Keep track of it
  // as inflight in case of error, so that it gets cleaned up properly.
  inflightBlock.reset(blockAndLoc.block);
}

// Populate the high level assembly state if necessary.
if (state.asmState)
  state.asmState->addDefinition(blockAndLoc.block, nameLoc);
block = blockAndLoc.block;

// If an argument list is present, parse it.
if (getToken().is(Token::l_paren))
  if (parseOptionalBlockArgList(block))
    return failure();
if (parseToken(Token::colon, "expected ':' after block name"))
  return failure();

// Parse the body of the block.
ParseResult res = parseBlockBody(block);

// If parsing was successful, drop the inflight block. We relinquish ownership
// back up to the caller.
if (succeeded(res))
  (void)inflightBlock.release();
return res;
2254}

2256ParseResult OperationParser::parseBlockBody(Block *block) {
// Set the insertion point to the end of the block to parse.
opBuilder.setInsertionPointToEnd(block);

// Parse the list of operations that make up the body of the block.
while (getToken().isNot(Token::caret_identifier, Token::r_brace))
  if (parseOperation())
    return failure();

return success();
2266}

2268/// Get the block with the specified name, creating it if it doesn't already
2269/// exist.  The location specified is the point of use, which allows
2270/// us to diagnose references to blocks that are not defined precisely.
2271Block *OperationParser::getBlockNamed(StringRef name, SMLoc loc) {
BlockDefinition &blockDef = getBlockInfoByName(name);
if (!blockDef.block) {
  blockDef = {new Block(), loc};
  insertForwardRef(blockDef.block, blockDef.loc);
}

// Populate the high level assembly state if necessary.
if (state.asmState)
  state.asmState->addUses(blockDef.block, loc);

return blockDef.block;
2283}

2285/// Parse a (possibly empty) list of SSA operands with types as block arguments
2286/// enclosed in parentheses.
2287///
2288///   value-id-and-type-list ::= value-id-and-type (`,` ssa-id-and-type)*
2289///   block-arg-list ::= `(` value-id-and-type-list? `)`
2290///
2291ParseResult OperationParser::parseOptionalBlockArgList(Block *owner) {
if (getToken().is(Token::r_brace))
  return success();

// If the block already has arguments, then we're handling the entry block.
// Parse and register the names for the arguments, but do not add them.
bool definingExistingArgs = owner->getNumArguments() != 0;
unsigned nextArgument = 0;

return parseCommaSeparatedList(Delimiter::Paren, [&]() -> ParseResult {
  return parseSSADefOrUseAndType(
      [&](UnresolvedOperand useInfo, Type type) -> ParseResult {
        BlockArgument arg;

        // If we are defining existing arguments, ensure that the argument
        // has already been created with the right type.
        if (definingExistingArgs) {
          // Otherwise, ensure that this argument has already been created.
          if (nextArgument >= owner->getNumArguments())
            return emitError("too many arguments specified in argument list");

          // Finally, make sure the existing argument has the correct type.
          arg = owner->getArgument(nextArgument++);
          if (arg.getType() != type)
            return emitError("argument and block argument type mismatch");
        } else {
          auto loc = getEncodedSourceLocation(useInfo.location);
          arg = owner->addArgument(type, loc);
        }

        // If the argument has an explicit loc(...) specifier, parse and apply
        // it.
        if (parseTrailingLocationSpecifier(arg))
          return failure();

        // Mark this block argument definition in the parser state if it was
        // provided.
        if (state.asmState)
          state.asmState->addDefinition(arg, useInfo.location);

        return addDefinition(useInfo, arg);
      });
});
2334}

2336//===----------------------------------------------------------------------===//
2337// Code Completion
2338//===----------------------------------------------------------------------===//

2340ParseResult OperationParser::codeCompleteSSAUse() {
std::string detailData;
llvm::raw_string_ostream detailOS(detailData);
for (IsolatedSSANameScope &scope : isolatedNameScopes) {
  for (auto &it : scope.values) {
    if (it.second.empty())
      continue;
    Value frontValue = it.second.front().value;

    // If the value isn't a forward reference, we also add the name of the op
    // to the detail.
    if (auto result = dyn_cast<OpResult>(frontValue)) {
      if (!forwardRefPlaceholders.count(result))
        detailOS << result.getOwner()->getName() << ": ";
    } else {
      detailOS << "arg #" << frontValue.cast<BlockArgument>().getArgNumber()
               << ": ";
    }

    // Emit the type of the values to aid with completion selection.
    detailOS << frontValue.getType();

    // FIXME: We should define a policy for packed values, e.g. with a limit
    // on the detail size, but it isn't clear what would be useful right now.
    // For now we just only emit the first type.
    if (it.second.size() > 1)
      detailOS << ", ...";

    state.codeCompleteContext->appendSSAValueCompletion(
        it.getKey(), std::move(detailOS.str()));
  }
}

return failure();
2374}

2376ParseResult OperationParser::codeCompleteBlock() {
// Don't provide completions if the token isn't empty, e.g. this avoids
// weirdness when we encounter a `.` within the identifier.
StringRef spelling = getTokenSpelling();
if (!(spelling.empty() || spelling == "^"))
  return failure();

for (const auto &it : blocksByName.back())
  state.codeCompleteContext->appendBlockCompletion(it.getFirst());
return failure();
2386}

2388//===----------------------------------------------------------------------===//
2389// Top-level entity parsing.
2390//===----------------------------------------------------------------------===//

2392namespace {
2393/// This parser handles entities that are only valid at the top level of the
2394/// file.
2395class TopLevelOperationParser : public Parser {
2396public:
explicit TopLevelOperationParser(ParserState &state) : Parser(state) {}

/// Parse a set of operations into the end of the given Block.
ParseResult parse(Block *topLevelBlock, Location parserLoc);

2402private:
/// Parse an attribute alias declaration.
///
///   attribute-alias-def ::= '#' alias-name `=` attribute-value
///
ParseResult parseAttributeAliasDef();

/// Parse a type alias declaration.
///
///   type-alias-def ::= '!' alias-name `=` type
///
ParseResult parseTypeAliasDef();

/// Parse a top-level file metadata dictionary.
///
///   file-metadata-dict ::= '{-#' file-metadata-entry* `#-}'
///
ParseResult parseFileMetadataDictionary();

/// Parse a resource metadata dictionary.
ParseResult parseResourceFileMetadata(
    function_ref<ParseResult(StringRef, SMLoc)> parseBody);
ParseResult parseDialectResourceFileMetadata();
ParseResult parseExternalResourceFileMetadata();
2426};

2428/// This class represents an implementation of a resource entry for the MLIR
2429/// textual format.
2430class ParsedResourceEntry : public AsmParsedResourceEntry {
2431public:
ParsedResourceEntry(StringRef key, SMLoc keyLoc, Token value, Parser &p)
    : key(key), keyLoc(keyLoc), value(value), p(p) {}
~ParsedResourceEntry() override = default;

StringRef getKey() const final { return key; }

InFlightDiagnostic emitError() const final { return p.emitError(keyLoc); }

AsmResourceEntryKind getKind() const final {
  if (value.isAny(Token::kw_true, Token::kw_false))
    return AsmResourceEntryKind::Bool;
  return value.getSpelling().startswith("\"0x")
             ? AsmResourceEntryKind::Blob
             : AsmResourceEntryKind::String;
}

FailureOr<bool> parseAsBool() const final {
  if (value.is(Token::kw_true))
    return true;
  if (value.is(Token::kw_false))
    return false;
  return p.emitError(value.getLoc(),
                     "expected 'true' or 'false' value for key '" + key +
                         "'");
}

FailureOr<std::string> parseAsString() const final {
  if (value.isNot(Token::string))
    return p.emitError(value.getLoc(),
                       "expected string value for key '" + key + "'");
  return value.getStringValue();
}

FailureOr<AsmResourceBlob>
parseAsBlob(BlobAllocatorFn allocator) const final {
  // Blob data within then textual format is represented as a hex string.
  // TODO: We could avoid an additional alloc+copy here if we pre-allocated
  // the buffer to use during hex processing.
  std::optional<std::string> blobData =
      value.is(Token::string) ? value.getHexStringValue() : std::nullopt;
  if (!blobData)
    return p.emitError(value.getLoc(),
                       "expected hex string blob for key '" + key + "'");

  // Extract the alignment of the blob data, which gets stored at the
  // beginning of the string.
  if (blobData->size() < sizeof(uint32_t)) {
    return p.emitError(value.getLoc(),
                       "expected hex string blob for key '" + key +
                           "' to encode alignment in first 4 bytes");
  }
  llvm::support::ulittle32_t align;
  memcpy(&align, blobData->data(), sizeof(uint32_t));

  // Get the data portion of the blob.
  StringRef data = StringRef(*blobData).drop_front(sizeof(uint32_t));
  if (data.empty())
    return AsmResourceBlob();

  // Allocate memory for the blob using the provided allocator and copy the
  // data into it.
  AsmResourceBlob blob = allocator(data.size(), align);
  assert(llvm::isAddrAligned(llvm::Align(align), blob.getData().data()) &&(static_cast <bool> (llvm::isAddrAligned(llvm::Align(align
), blob.getData().data()) && blob.isMutable() &&
 "blob allocator did not return a properly aligned address") ?
 void (0) : __assert_fail ("llvm::isAddrAligned(llvm::Align(align), blob.getData().data()) && blob.isMutable() && \"blob allocator did not return a properly aligned address\""
, "mlir/lib/AsmParser/Parser.cpp", 2496, __extension__ __PRETTY_FUNCTION__
))
         blob.isMutable() &&(static_cast <bool> (llvm::isAddrAligned(llvm::Align(align
), blob.getData().data()) && blob.isMutable() &&
 "blob allocator did not return a properly aligned address") ?
 void (0) : __assert_fail ("llvm::isAddrAligned(llvm::Align(align), blob.getData().data()) && blob.isMutable() && \"blob allocator did not return a properly aligned address\""
, "mlir/lib/AsmParser/Parser.cpp", 2496, __extension__ __PRETTY_FUNCTION__
))
         "blob allocator did not return a properly aligned address")(static_cast <bool> (llvm::isAddrAligned(llvm::Align(align
), blob.getData().data()) && blob.isMutable() &&
 "blob allocator did not return a properly aligned address") ?
 void (0) : __assert_fail ("llvm::isAddrAligned(llvm::Align(align), blob.getData().data()) && blob.isMutable() && \"blob allocator did not return a properly aligned address\""
, "mlir/lib/AsmParser/Parser.cpp", 2496, __extension__ __PRETTY_FUNCTION__
));
  memcpy(blob.getMutableData().data(), data.data(), data.size());
  return blob;
}

2501private:
StringRef key;
SMLoc keyLoc;
Token value;
Parser &p;
2506};
2507} // namespace

2509ParseResult TopLevelOperationParser::parseAttributeAliasDef() {
assert(getToken().is(Token::hash_identifier))(static_cast <bool> (getToken().is(Token::hash_identifier
)) ? void (0) : __assert_fail ("getToken().is(Token::hash_identifier)"
, "mlir/lib/AsmParser/Parser.cpp", 2510, __extension__ __PRETTY_FUNCTION__
));
StringRef aliasName = getTokenSpelling().drop_front();

// Check for redefinitions.
if (state.symbols.attributeAliasDefinitions.count(aliasName) > 0)
  return emitError("redefinition of attribute alias id '" + aliasName + "'");

// Make sure this isn't invading the dialect attribute namespace.
if (aliasName.contains('.'))
  return emitError("attribute names with a '.' are reserved for "
                   "dialect-defined names");

consumeToken(Token::hash_identifier);

// Parse the '='.
if (parseToken(Token::equal, "expected '=' in attribute alias definition"))
  return failure();

// Parse the attribute value.
Attribute attr = parseAttribute();
if (!attr)
  return failure();

state.symbols.attributeAliasDefinitions[aliasName] = attr;
return success();
2535}

2537ParseResult TopLevelOperationParser::parseTypeAliasDef() {
assert(getToken().is(Token::exclamation_identifier))(static_cast <bool> (getToken().is(Token::exclamation_identifier
)) ? void (0) : __assert_fail ("getToken().is(Token::exclamation_identifier)"
, "mlir/lib/AsmParser/Parser.cpp", 2538, __extension__ __PRETTY_FUNCTION__
));
StringRef aliasName = getTokenSpelling().drop_front();

// Check for redefinitions.
if (state.symbols.typeAliasDefinitions.count(aliasName) > 0)
  return emitError("redefinition of type alias id '" + aliasName + "'");

// Make sure this isn't invading the dialect type namespace.
if (aliasName.contains('.'))
  return emitError("type names with a '.' are reserved for "
                   "dialect-defined names");
consumeToken(Token::exclamation_identifier);

// Parse the '='.
if (parseToken(Token::equal, "expected '=' in type alias definition"))
  return failure();

// Parse the type.
Type aliasedType = parseType();
if (!aliasedType)
  return failure();

// Register this alias with the parser state.
state.symbols.typeAliasDefinitions.try_emplace(aliasName, aliasedType);
return success();
2563}

2565ParseResult TopLevelOperationParser::parseFileMetadataDictionary() {
consumeToken(Token::file_metadata_begin);
return parseCommaSeparatedListUntil(
    Token::file_metadata_end, [&]() -> ParseResult {
      // Parse the key of the metadata dictionary.
      SMLoc keyLoc = getToken().getLoc();
      StringRef key;
      if (failed(parseOptionalKeyword(&key)))
        return emitError("expected identifier key in file "
                         "metadata dictionary");
      if (parseToken(Token::colon, "expected ':'"))
        return failure();

      // Process the metadata entry.
      if (key == "dialect_resources")
        return parseDialectResourceFileMetadata();
      if (key == "external_resources")
        return parseExternalResourceFileMetadata();
      return emitError(keyLoc, "unknown key '" + key +
                                   "' in file metadata dictionary");
    });
2586}

2588ParseResult TopLevelOperationParser::parseResourceFileMetadata(
  function_ref<ParseResult(StringRef, SMLoc)> parseBody) {
if (parseToken(Token::l_brace, "expected '{'"))
  return failure();

return parseCommaSeparatedListUntil(Token::r_brace, [&]() -> ParseResult {
  // Parse the top-level name entry.
  SMLoc nameLoc = getToken().getLoc();
  StringRef name;
  if (failed(parseOptionalKeyword(&name)))
    return emitError("expected identifier key for 'resource' entry");

  if (parseToken(Token::colon, "expected ':'") ||
      parseToken(Token::l_brace, "expected '{'"))
    return failure();
  return parseBody(name, nameLoc);
});
2605}

2607ParseResult TopLevelOperationParser::parseDialectResourceFileMetadata() {
return parseResourceFileMetadata([&](StringRef name,
                                     SMLoc nameLoc) -> ParseResult {
  // Lookup the dialect and check that it can handle a resource entry.
  Dialect *dialect = getContext()->getOrLoadDialect(name);
  if (!dialect)
    return emitError(nameLoc, "dialect '" + name + "' is unknown");
  const auto *handler = dyn_cast<OpAsmDialectInterface>(dialect);
  if (!handler) {
    return emitError() << "unexpected 'resource' section for dialect '"
                       << dialect->getNamespace() << "'";
  }

  return parseCommaSeparatedListUntil(Token::r_brace, [&]() -> ParseResult {
    // Parse the name of the resource entry.
    SMLoc keyLoc = getToken().getLoc();
    StringRef key;
    if (failed(parseResourceHandle(handler, key)) ||
        parseToken(Token::colon, "expected ':'"))
      return failure();
    Token valueTok = getToken();
    consumeToken();

    ParsedResourceEntry entry(key, keyLoc, valueTok, *this);
    return handler->parseResource(entry);
  });
});
2634}

2636ParseResult TopLevelOperationParser::parseExternalResourceFileMetadata() {
return parseResourceFileMetadata([&](StringRef name,
                                     SMLoc nameLoc) -> ParseResult {
  AsmResourceParser *handler = state.config.getResourceParser(name);

  // TODO: Should we require handling external resources in some scenarios?
  if (!handler) {
    emitWarning(getEncodedSourceLocation(nameLoc))
        << "ignoring unknown external resources for '" << name << "'";
  }

  return parseCommaSeparatedListUntil(Token::r_brace, [&]() -> ParseResult {
    // Parse the name of the resource entry.
    SMLoc keyLoc = getToken().getLoc();
    StringRef key;
    if (failed(parseOptionalKeyword(&key)))
      return emitError(
          "expected identifier key for 'external_resources' entry");
    if (parseToken(Token::colon, "expected ':'"))
      return failure();
    Token valueTok = getToken();
    consumeToken();

    if (!handler)
      return success();
    ParsedResourceEntry entry(key, keyLoc, valueTok, *this);
    return handler->parseResource(entry);
  });
});
2665}

2667ParseResult TopLevelOperationParser::parse(Block *topLevelBlock,
                                         Location parserLoc) {
// Create a top-level operation to contain the parsed state.
OwningOpRef<ModuleOp> topLevelOp(ModuleOp::create(parserLoc));
OperationParser opParser(state, topLevelOp.get());
while (true) {
  switch (getToken().getKind()) {
  default:
    // Parse a top-level operation.
    if (opParser.parseOperation())
      return failure();
    break;

  // If we got to the end of the file, then we're done.
  case Token::eof: {
    if (opParser.finalize())
      return failure();

    // Splice the blocks of the parsed operation over to the provided
    // top-level block.
    auto &parsedOps = topLevelOp->getBody()->getOperations();
    auto &destOps = topLevelBlock->getOperations();
    destOps.splice(destOps.end(), parsedOps, parsedOps.begin(),
                   parsedOps.end());
    return success();
  }

  // If we got an error token, then the lexer already emitted an error, just
  // stop.  Someday we could introduce error recovery if there was demand
  // for it.
  case Token::error:
    return failure();

  // Parse an attribute alias.
  case Token::hash_identifier:
    if (parseAttributeAliasDef())
      return failure();
    break;

  // Parse a type alias.
  case Token::exclamation_identifier:
    if (parseTypeAliasDef())
      return failure();
    break;

    // Parse a file-level metadata dictionary.
  case Token::file_metadata_begin:
    if (parseFileMetadataDictionary())
      return failure();
    break;
  }
}
2719}

2721//===----------------------------------------------------------------------===//

2723LogicalResult
2724mlir::parseAsmSourceFile(const llvm::SourceMgr &sourceMgr, Block *block,
                       const ParserConfig &config, AsmParserState *asmState,
                       AsmParserCodeCompleteContext *codeCompleteContext) {
const auto *sourceBuf = sourceMgr.getMemoryBuffer(sourceMgr.getMainFileID());

Location parserLoc =
    FileLineColLoc::get(config.getContext(), sourceBuf->getBufferIdentifier(),
                        /*line=*/0, /*column=*/0);

SymbolState aliasState;
ParserState state(sourceMgr, config, aliasState, asmState,
                  codeCompleteContext);
return TopLevelOperationParser(state).parse(block, parserLoc);
2737}