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Merged
merged 2 commits into from
Jul 22, 2016
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Parse bounds declarations for function return values. #21

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d85873e
Parse bounds declarations for function return values.
dtarditi Jul 20, 2016
f65ff0e
Address code review feedback and improve an error message.
dtarditi Jul 22, 2016
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9 changes: 8 additions & 1 deletion include/clang/AST/Decl.h
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Expand Up @@ -1584,6 +1584,8 @@ class FunctionDecl : public DeclaratorDecl, public DeclContext,
/// 'enum Y' in 'void f(enum Y {AA} x) {}'.
ArrayRef<NamedDecl *> DeclsInPrototypeScope;

BoundsExpr *ReturnBoundsExpr;

LazyDeclStmtPtr Body;

// FIXME: This can be packed into the bitfields in DeclContext.
Expand Down Expand Up @@ -1687,7 +1689,7 @@ class FunctionDecl : public DeclaratorDecl, public DeclContext,
StartLoc),
DeclContext(DK),
redeclarable_base(C),
ParamInfo(nullptr), Body(),
ParamInfo(nullptr), ReturnBoundsExpr(nullptr), Body(),
SClass(S),
IsInline(isInlineSpecified), IsInlineSpecified(isInlineSpecified),
IsVirtualAsWritten(false), IsPure(false), HasInheritedPrototype(false),
Expand Down Expand Up @@ -2065,6 +2067,11 @@ class FunctionDecl : public DeclaratorDecl, public DeclContext,
/// computed linkage of symbol, see getLinkage.
StorageClass getStorageClass() const { return StorageClass(SClass); }

/// \brief Returns the bounds expression for the return value of this function, if
/// any.
BoundsExpr *getReturnBoundsExpr() { return ReturnBoundsExpr; }
void setReturnBoundsExpr(BoundsExpr *E) { ReturnBoundsExpr = E; }

/// \brief Determine whether the "inline" keyword was specified for this
/// function.
bool isInlineSpecified() const { return IsInlineSpecified; }
Expand Down
16 changes: 16 additions & 0 deletions include/clang/Sema/DeclSpec.h
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Expand Up @@ -1287,11 +1287,18 @@ struct DeclaratorChunk {
/// \brief The end location of the exception specification, if any.
unsigned ExceptionSpecLocEnd;

/// The location of the ':' for the return bounds expression in the source
unsigned ReturnBoundsColonLoc;

/// Params - This is a pointer to a new[]'d array of ParamInfo objects that
/// describe the parameters specified by this function declarator. null if
/// there are no parameters specified.
ParamInfo *Params;

/// The bounds for the value returned by the function. Null if there is
/// no bounds specified.
BoundsExpr *ReturnBounds;

union {
/// \brief Pointer to a new[]'d array of TypeAndRange objects that
/// contain the types in the function's dynamic exception specification
Expand Down Expand Up @@ -1352,6 +1359,10 @@ struct DeclaratorChunk {
return SourceLocation::getFromRawEncoding(RParenLoc);
}

SourceLocation getReturnBoundsColonLoc() const {
return SourceLocation::getFromRawEncoding(ReturnBoundsColonLoc);
}

SourceLocation getExceptionSpecLocBeg() const {
return SourceLocation::getFromRawEncoding(ExceptionSpecLocBeg);
}
Expand Down Expand Up @@ -1408,6 +1419,9 @@ struct DeclaratorChunk {

/// \brief Get the trailing-return-type for this function declarator.
ParsedType getTrailingReturnType() const { return TrailingReturnType; }

/// \brief The bounds expression for the return value
BoundsExpr *getReturnBounds() const { return ReturnBounds; }
};

struct BlockPointerTypeInfo : TypeInfoCommon {
Expand Down Expand Up @@ -1552,6 +1566,8 @@ struct DeclaratorChunk {
CachedTokens *ExceptionSpecTokens,
SourceLocation LocalRangeBegin,
SourceLocation LocalRangeEnd,
SourceLocation ReturnBoundsColonLoc,
BoundsExpr *ReturnBoundsExpr,
Declarator &TheDeclarator,
TypeResult TrailingReturnType =
TypeResult());
Expand Down
1 change: 1 addition & 0 deletions include/clang/Sema/Sema.h
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Expand Up @@ -4116,6 +4116,7 @@ class Sema {

void ActOnBoundsExpr(VarDecl *D, BoundsExpr *Expr);
void ActOnInvalidBoundsExpr(VarDecl *D);
BoundsExpr *CreateInvalidBoundsExpr();

//===---------------------------- Clang Extensions ----------------------===//

Expand Down
23 changes: 22 additions & 1 deletion lib/Parse/ParseDecl.cpp
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Expand Up @@ -5586,6 +5586,10 @@ void Parser::ParseParenDeclarator(Declarator &D) {
/// dynamic-exception-specification
/// noexcept-specification
///
/// For Checked C, after the parameter-list, it also parses the optional return
/// bounds expression for the function declarator:
/// [Checked C] ':' bounds-expression
////
void Parser::ParseFunctionDeclarator(Declarator &D,
ParsedAttributes &FirstArgAttrs,
BalancedDelimiterTracker &Tracker,
Expand Down Expand Up @@ -5626,6 +5630,8 @@ void Parser::ParseFunctionDeclarator(Declarator &D,
SourceLocation LParenLoc, RParenLoc;
LParenLoc = Tracker.getOpenLocation();
StartLoc = LParenLoc;
SourceLocation BoundsColonLoc;
BoundsExpr *ReturnBoundsExpr = nullptr;

if (isFunctionDeclaratorIdentifierList()) {
if (RequiresArg)
Expand Down Expand Up @@ -5741,6 +5747,19 @@ void Parser::ParseFunctionDeclarator(Declarator &D,
}
}

// Parse optional Checked C bounds expression with the form:
// ':' bounds-expression.
if (getLangOpts().CheckedC && Tok.is(tok::colon)) {
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if (getLangOpts().CheckedC && Tok.is(tok::colon)) { [](start = 2, length = 51)

I know you called it out in the header comment for this function, but a quick brief comment calling out that this is for the return bounds expression might be nice (similar to the ones in the few code chunks directly above).

BoundsColonLoc = Tok.getLocation();
ConsumeToken();
ExprResult BoundsExprResult = ParseBoundsExpression();
if (BoundsExprResult.isInvalid()) {
ReturnBoundsExpr = Actions.CreateInvalidBoundsExpr();
SkipUntil(tok::l_brace, SkipUntilFlags::StopAtSemi | SkipUntilFlags::StopBeforeMatch);
} else
ReturnBoundsExpr = cast<BoundsExpr>(BoundsExprResult.get());
}

// Remember that we parsed a function type, and remember the attributes.
D.AddTypeInfo(DeclaratorChunk::getFunction(HasProto,
IsAmbiguous,
Expand All @@ -5760,7 +5779,9 @@ void Parser::ParseFunctionDeclarator(Declarator &D,
NoexceptExpr.isUsable() ?
NoexceptExpr.get() : nullptr,
ExceptionSpecTokens,
StartLoc, LocalEndLoc, D,
StartLoc, LocalEndLoc,
BoundsColonLoc, ReturnBoundsExpr,
D,
TrailingReturnType),
FnAttrs, EndLoc);
}
Expand Down
17 changes: 13 additions & 4 deletions lib/Parse/ParseExpr.cpp
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Expand Up @@ -2795,10 +2795,8 @@ ExprResult Parser::ParseBoundsExpression() {
ExprResult LowerBound =
Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression());

if (ExpectAndConsume(tok::comma))
// We didn't find a comma, so don't try to parse the upper bounds expression.
Result = ExprError();
else {
if (Tok.getKind() == tok::comma) {
ConsumeToken();
ExprResult UpperBound =
Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression());
if (LowerBound.isInvalid() || UpperBound.isInvalid())
Expand All @@ -2807,6 +2805,15 @@ ExprResult Parser::ParseBoundsExpression() {
Result = Actions.ActOnRangeBoundsExpr(BoundsKWLoc, LowerBound.get(),
UpperBound.get(),
Tok.getLocation());
} else {
// We didn't find a comma. Only issue an error message if the
// LowerBound expression is valid. Otherwise, we already issued an
// error message when parsing the lower bound. Emitting an error
// message here could be spurious or confusing.
if (!LowerBound.isInvalid()) {
Diag(Tok, diag::err_expected) << tok::comma;
}
Result = ExprError();
}
} // if (!FoundNullaryOperator)
} else {
Expand Down Expand Up @@ -2971,6 +2978,8 @@ ExprResult Parser::ParseBlockLiteralExpression() {
/*NoexceptExpr=*/nullptr,
/*ExceptionSpecTokens=*/nullptr,
CaretLoc, CaretLoc,
/*ReturnBoundsColon=*/NoLoc,
/*ReturnBoundsExpr=*/nullptr,
ParamInfo),
attrs, CaretLoc);

Expand Down
10 changes: 8 additions & 2 deletions lib/Parse/ParseExprCXX.cpp
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Expand Up @@ -1221,7 +1221,10 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer(
NoexceptExpr.isUsable() ?
NoexceptExpr.get() : nullptr,
/*ExceptionSpecTokens*/nullptr,
LParenLoc, FunLocalRangeEnd, D,
LParenLoc, FunLocalRangeEnd,
/*ReturnBoundsColonLoc=*/NoLoc,
/*ReturnBoundsExpr=*/nullptr,
D,
TrailingReturnType),
Attr, DeclEndLoc);
} else if (Tok.isOneOf(tok::kw_mutable, tok::arrow, tok::kw___attribute,
Expand Down Expand Up @@ -1290,7 +1293,10 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer(
/*NumExceptions=*/0,
/*NoexceptExpr=*/nullptr,
/*ExceptionSpecTokens=*/nullptr,
DeclLoc, DeclEndLoc, D,
DeclLoc, DeclEndLoc,
/*ReturnBoundsColonLoc=*/NoLoc,
/*ReturnBoundsExpr=*/nullptr,
D,
TrailingReturnType),
Attr, DeclEndLoc);
}
Expand Down
4 changes: 4 additions & 0 deletions lib/Sema/DeclSpec.cpp
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Expand Up @@ -175,6 +175,8 @@ DeclaratorChunk DeclaratorChunk::getFunction(bool hasProto,
CachedTokens *ExceptionSpecTokens,
SourceLocation LocalRangeBegin,
SourceLocation LocalRangeEnd,
SourceLocation ReturnBoundsColonLoc,
BoundsExpr *ReturnBoundsExpr,
Declarator &TheDeclarator,
TypeResult TrailingReturnType) {
assert(!(TypeQuals & DeclSpec::TQ_atomic) &&
Expand Down Expand Up @@ -210,6 +212,8 @@ DeclaratorChunk DeclaratorChunk::getFunction(bool hasProto,
I.Fun.HasTrailingReturnType = TrailingReturnType.isUsable() ||
TrailingReturnType.isInvalid();
I.Fun.TrailingReturnType = TrailingReturnType.get();
I.Fun.ReturnBoundsColonLoc = ReturnBoundsColonLoc.getRawEncoding();
I.Fun.ReturnBounds = ReturnBoundsExpr;

assert(I.Fun.TypeQuals == TypeQuals && "bitfield overflow");
assert(I.Fun.ExceptionSpecType == ESpecType && "bitfield overflow");
Expand Down
22 changes: 19 additions & 3 deletions lib/Sema/SemaDecl.cpp
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Expand Up @@ -7973,6 +7973,14 @@ Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
// Finally, we know we have the right number of parameters, install them.
NewFD->setParams(Params);

// TODO: clang-checked-issue #20. Issue #20 is attaching bounds information
// to function types. After it is address, we need to make sure that bounds
// information is propgated to newFD from the FunctionPrototype instance.
if (D.isFunctionDeclarator()) {
DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
NewFD->setReturnBoundsExpr(FTI.getReturnBounds());
}

// Find all anonymous symbols defined during the declaration of this function
// and add to NewFD. This lets us track decls such 'enum Y' in:
//
Expand Down Expand Up @@ -10880,13 +10888,19 @@ void Sema::ActOnInvalidBoundsExpr(VarDecl *D) {
if (!D)
return;

BoundsExpr *InvalidExpr = CreateInvalidBoundsExpr();
D->setBoundsExpr(InvalidExpr);
}

BoundsExpr *Sema::CreateInvalidBoundsExpr() {
ExprResult Result =
ActOnNullaryBoundsExpr(SourceLocation(),
NullaryBoundsExpr::Kind::Invalid,
SourceLocation());

if (!Result.isInvalid())
D->setBoundsExpr(cast<BoundsExpr>(Result.get()));
return cast<BoundsExpr>(Result.get());
else
return nullptr;
}

Decl *
Expand Down Expand Up @@ -11613,7 +11627,9 @@ NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc,
/*NumExceptions=*/0,
/*NoexceptExpr=*/nullptr,
/*ExceptionSpecTokens=*/nullptr,
Loc, Loc, D),
Loc, Loc,
/*ReturnBoundsColonLoc=*/NoLoc,
/*ReturnBoundsExpr=*/nullptr, D),
DS.getAttributes(),
SourceLocation());
D.SetIdentifier(&II, Loc);
Expand Down
9 changes: 8 additions & 1 deletion lib/Sema/SemaType.cpp
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Expand Up @@ -718,7 +718,10 @@ static void maybeSynthesizeBlockSignature(TypeProcessingState &state,
/*NumExceptions=*/0,
/*NoexceptExpr=*/nullptr,
/*ExceptionSpecTokens=*/nullptr,
loc, loc, declarator));
loc, loc,
/*ReturnBoundsColon=*/NoLoc,
/*ReturnBoundsExpr=*/nullptr,
declarator));

// For consistency, make sure the state still has us as processing
// the decl spec.
Expand Down Expand Up @@ -4238,6 +4241,10 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
SmallVector<QualType, 16> ParamTys;
ParamTys.reserve(FTI.NumParams);

// TODO: checkedc-clang issue #20: represent bounds information
// in function types. The code below will need to be updated
// to add the bounds information to the FunctionType.

SmallVector<FunctionProtoType::ExtParameterInfo, 16>
ExtParameterInfos(FTI.NumParams);
bool HasAnyInterestingExtParameterInfos = false;
Expand Down