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//===--- SemaAttr.cpp - Semantic Analysis for Attributes ------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements semantic analysis for non-trivial attributes and
// pragmas.
//
//===----------------------------------------------------------------------===//
#include "clang/AST/ASTConsumer.h"
#include "clang/AST/Attr.h"
#include "clang/AST/Expr.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Sema/Lookup.h"
#include "clang/Sema/SemaInternal.h"
using namespace clang;
//===----------------------------------------------------------------------===//
// Pragma 'pack' and 'options align'
//===----------------------------------------------------------------------===//
Sema::PragmaStackSentinelRAII::PragmaStackSentinelRAII(Sema &S,
StringRef SlotLabel,
bool ShouldAct)
: S(S), SlotLabel(SlotLabel), ShouldAct(ShouldAct) {
if (ShouldAct) {
S.VtorDispStack.SentinelAction(PSK_Push, SlotLabel);
S.DataSegStack.SentinelAction(PSK_Push, SlotLabel);
S.BSSSegStack.SentinelAction(PSK_Push, SlotLabel);
S.ConstSegStack.SentinelAction(PSK_Push, SlotLabel);
S.CodeSegStack.SentinelAction(PSK_Push, SlotLabel);
}
}
Sema::PragmaStackSentinelRAII::~PragmaStackSentinelRAII() {
if (ShouldAct) {
S.VtorDispStack.SentinelAction(PSK_Pop, SlotLabel);
S.DataSegStack.SentinelAction(PSK_Pop, SlotLabel);
S.BSSSegStack.SentinelAction(PSK_Pop, SlotLabel);
S.ConstSegStack.SentinelAction(PSK_Pop, SlotLabel);
S.CodeSegStack.SentinelAction(PSK_Pop, SlotLabel);
}
}
void Sema::AddAlignmentAttributesForRecord(RecordDecl *RD) {
// If there is no pack value, we don't need any attributes.
if (!PackStack.CurrentValue)
return;
// Otherwise, check to see if we need a max field alignment attribute.
if (unsigned Alignment = PackStack.CurrentValue) {
if (Alignment == Sema::kMac68kAlignmentSentinel)
RD->addAttr(AlignMac68kAttr::CreateImplicit(Context));
else
RD->addAttr(MaxFieldAlignmentAttr::CreateImplicit(Context,
Alignment * 8));
}
if (PackIncludeStack.empty())
return;
// The #pragma pack affected a record in an included file, so Clang should
// warn when that pragma was written in a file that included the included
// file.
for (auto &PackedInclude : llvm::reverse(PackIncludeStack)) {
if (PackedInclude.CurrentPragmaLocation != PackStack.CurrentPragmaLocation)
break;
if (PackedInclude.HasNonDefaultValue)
PackedInclude.ShouldWarnOnInclude = true;
}
}
void Sema::AddMsStructLayoutForRecord(RecordDecl *RD) {
if (MSStructPragmaOn)
RD->addAttr(MSStructAttr::CreateImplicit(Context));
// FIXME: We should merge AddAlignmentAttributesForRecord with
// AddMsStructLayoutForRecord into AddPragmaAttributesForRecord, which takes
// all active pragmas and applies them as attributes to class definitions.
if (VtorDispStack.CurrentValue != getLangOpts().getVtorDispMode())
RD->addAttr(MSVtorDispAttr::CreateImplicit(
Context, unsigned(VtorDispStack.CurrentValue)));
}
template <typename Attribute>
static void addGslOwnerPointerAttributeIfNotExisting(ASTContext &Context,
CXXRecordDecl *Record) {
if (Record->hasAttr<OwnerAttr>() || Record->hasAttr<PointerAttr>())
return;
for (Decl *Redecl : Record->redecls())
Redecl->addAttr(Attribute::CreateImplicit(Context, /*DerefType=*/nullptr));
}
void Sema::inferGslPointerAttribute(NamedDecl *ND,
CXXRecordDecl *UnderlyingRecord) {
if (!UnderlyingRecord)
return;
const auto *Parent = dyn_cast<CXXRecordDecl>(ND->getDeclContext());
if (!Parent)
return;
static llvm::StringSet<> Containers{
"array",
"basic_string",
"deque",
"forward_list",
"vector",
"list",
"map",
"multiset",
"multimap",
"priority_queue",
"queue",
"set",
"stack",
"unordered_set",
"unordered_map",
"unordered_multiset",
"unordered_multimap",
};
static llvm::StringSet<> Iterators{"iterator", "const_iterator",
"reverse_iterator",
"const_reverse_iterator"};
if (Parent->isInStdNamespace() && Iterators.count(ND->getName()) &&
Containers.count(Parent->getName()))
addGslOwnerPointerAttributeIfNotExisting<PointerAttr>(Context,
UnderlyingRecord);
}
void Sema::inferGslPointerAttribute(TypedefNameDecl *TD) {
QualType Canonical = TD->getUnderlyingType().getCanonicalType();
CXXRecordDecl *RD = Canonical->getAsCXXRecordDecl();
if (!RD) {
if (auto *TST =
dyn_cast<TemplateSpecializationType>(Canonical.getTypePtr())) {
RD = dyn_cast_or_null<CXXRecordDecl>(
TST->getTemplateName().getAsTemplateDecl()->getTemplatedDecl());
}
}
inferGslPointerAttribute(TD, RD);
}
void Sema::inferGslOwnerPointerAttribute(CXXRecordDecl *Record) {
static llvm::StringSet<> StdOwners{
"any",
"array",
"basic_regex",
"basic_string",
"deque",
"forward_list",
"vector",
"list",
"map",
"multiset",
"multimap",
"optional",
"priority_queue",
"queue",
"set",
"stack",
"unique_ptr",
"unordered_set",
"unordered_map",
"unordered_multiset",
"unordered_multimap",
"variant",
};
static llvm::StringSet<> StdPointers{
"basic_string_view",
"reference_wrapper",
"regex_iterator",
};
if (!Record->getIdentifier())
return;
// Handle classes that directly appear in std namespace.
if (Record->isInStdNamespace()) {
if (Record->hasAttr<OwnerAttr>() || Record->hasAttr<PointerAttr>())
return;
if (StdOwners.count(Record->getName()))
addGslOwnerPointerAttributeIfNotExisting<OwnerAttr>(Context, Record);
else if (StdPointers.count(Record->getName()))
addGslOwnerPointerAttributeIfNotExisting<PointerAttr>(Context, Record);
return;
}
// Handle nested classes that could be a gsl::Pointer.
inferGslPointerAttribute(Record, Record);
}
void Sema::ActOnPragmaOptionsAlign(PragmaOptionsAlignKind Kind,
SourceLocation PragmaLoc) {
PragmaMsStackAction Action = Sema::PSK_Reset;
unsigned Alignment = 0;
switch (Kind) {
// For all targets we support native and natural are the same.
//
// FIXME: This is not true on Darwin/PPC.
case POAK_Native:
case POAK_Power:
case POAK_Natural:
Action = Sema::PSK_Push_Set;
Alignment = 0;
break;
// Note that '#pragma options align=packed' is not equivalent to attribute
// packed, it has a different precedence relative to attribute aligned.
case POAK_Packed:
Action = Sema::PSK_Push_Set;
Alignment = 1;
break;
case POAK_Mac68k:
// Check if the target supports this.
if (!this->Context.getTargetInfo().hasAlignMac68kSupport()) {
Diag(PragmaLoc, diag::err_pragma_options_align_mac68k_target_unsupported);
return;
}
Action = Sema::PSK_Push_Set;
Alignment = Sema::kMac68kAlignmentSentinel;
break;
case POAK_Reset:
// Reset just pops the top of the stack, or resets the current alignment to
// default.
Action = Sema::PSK_Pop;
if (PackStack.Stack.empty()) {
if (PackStack.CurrentValue) {
Action = Sema::PSK_Reset;
} else {
Diag(PragmaLoc, diag::warn_pragma_options_align_reset_failed)
<< "stack empty";
return;
}
}
break;
}
PackStack.Act(PragmaLoc, Action, StringRef(), Alignment);
}
void Sema::ActOnPragmaClangSection(SourceLocation PragmaLoc, PragmaClangSectionAction Action,
PragmaClangSectionKind SecKind, StringRef SecName) {
PragmaClangSection *CSec;
int SectionFlags = ASTContext::PSF_Read;
switch (SecKind) {
case PragmaClangSectionKind::PCSK_BSS:
CSec = &PragmaClangBSSSection;
SectionFlags |= ASTContext::PSF_Write | ASTContext::PSF_ZeroInit;
break;
case PragmaClangSectionKind::PCSK_Data:
CSec = &PragmaClangDataSection;
SectionFlags |= ASTContext::PSF_Write;
break;
case PragmaClangSectionKind::PCSK_Rodata:
CSec = &PragmaClangRodataSection;
break;
case PragmaClangSectionKind::PCSK_Relro:
CSec = &PragmaClangRelroSection;
break;
case PragmaClangSectionKind::PCSK_Text:
CSec = &PragmaClangTextSection;
SectionFlags |= ASTContext::PSF_Execute;
break;
default:
llvm_unreachable("invalid clang section kind");
}
if (Action == PragmaClangSectionAction::PCSA_Clear) {
CSec->Valid = false;
return;
}
if (UnifySection(SecName, SectionFlags, PragmaLoc))
return;
CSec->Valid = true;
CSec->SectionName = std::string(SecName);
CSec->PragmaLocation = PragmaLoc;
}
void Sema::ActOnPragmaPack(SourceLocation PragmaLoc, PragmaMsStackAction Action,
StringRef SlotLabel, Expr *alignment) {
Expr *Alignment = static_cast<Expr *>(alignment);
// If specified then alignment must be a "small" power of two.
unsigned AlignmentVal = 0;
if (Alignment) {
Optional<llvm::APSInt> Val;
// pack(0) is like pack(), which just works out since that is what
// we use 0 for in PackAttr.
if (Alignment->isTypeDependent() || Alignment->isValueDependent() ||
!(Val = Alignment->getIntegerConstantExpr(Context)) ||
!(*Val == 0 || Val->isPowerOf2()) || Val->getZExtValue() > 16) {
Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment);
return; // Ignore
}
AlignmentVal = (unsigned)Val->getZExtValue();
}
if (Action == Sema::PSK_Show) {
// Show the current alignment, making sure to show the right value
// for the default.
// FIXME: This should come from the target.
AlignmentVal = PackStack.CurrentValue;
if (AlignmentVal == 0)
AlignmentVal = 8;
if (AlignmentVal == Sema::kMac68kAlignmentSentinel)
Diag(PragmaLoc, diag::warn_pragma_pack_show) << "mac68k";
else
Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal;
}
// MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack:
// "#pragma pack(pop, identifier, n) is undefined"
if (Action & Sema::PSK_Pop) {
if (Alignment && !SlotLabel.empty())
Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifier_and_alignment);
if (PackStack.Stack.empty())
Diag(PragmaLoc, diag::warn_pragma_pop_failed) << "pack" << "stack empty";
}
PackStack.Act(PragmaLoc, Action, SlotLabel, AlignmentVal);
}
void Sema::DiagnoseNonDefaultPragmaPack(PragmaPackDiagnoseKind Kind,
SourceLocation IncludeLoc) {
if (Kind == PragmaPackDiagnoseKind::NonDefaultStateAtInclude) {
SourceLocation PrevLocation = PackStack.CurrentPragmaLocation;
// Warn about non-default alignment at #includes (without redundant
// warnings for the same directive in nested includes).
// The warning is delayed until the end of the file to avoid warnings
// for files that don't have any records that are affected by the modified
// alignment.
bool HasNonDefaultValue =
PackStack.hasValue() &&
(PackIncludeStack.empty() ||
PackIncludeStack.back().CurrentPragmaLocation != PrevLocation);
PackIncludeStack.push_back(
{PackStack.CurrentValue,
PackStack.hasValue() ? PrevLocation : SourceLocation(),
HasNonDefaultValue, /*ShouldWarnOnInclude*/ false});
return;
}
assert(Kind == PragmaPackDiagnoseKind::ChangedStateAtExit && "invalid kind");
PackIncludeState PrevPackState = PackIncludeStack.pop_back_val();
if (PrevPackState.ShouldWarnOnInclude) {
// Emit the delayed non-default alignment at #include warning.
Diag(IncludeLoc, diag::warn_pragma_pack_non_default_at_include);
Diag(PrevPackState.CurrentPragmaLocation, diag::note_pragma_pack_here);
}
// Warn about modified alignment after #includes.
if (PrevPackState.CurrentValue != PackStack.CurrentValue) {
Diag(IncludeLoc, diag::warn_pragma_pack_modified_after_include);
Diag(PackStack.CurrentPragmaLocation, diag::note_pragma_pack_here);
}
}
void Sema::DiagnoseUnterminatedPragmaPack() {
if (PackStack.Stack.empty())
return;
bool IsInnermost = true;
for (const auto &StackSlot : llvm::reverse(PackStack.Stack)) {
Diag(StackSlot.PragmaPushLocation, diag::warn_pragma_pack_no_pop_eof);
// The user might have already reset the alignment, so suggest replacing
// the reset with a pop.
if (IsInnermost && PackStack.CurrentValue == PackStack.DefaultValue) {
auto DB = Diag(PackStack.CurrentPragmaLocation,
diag::note_pragma_pack_pop_instead_reset);
SourceLocation FixItLoc = Lexer::findLocationAfterToken(
PackStack.CurrentPragmaLocation, tok::l_paren, SourceMgr, LangOpts,
/*SkipTrailing=*/false);
if (FixItLoc.isValid())
DB << FixItHint::CreateInsertion(FixItLoc, "pop");
}
IsInnermost = false;
}
}
void Sema::ActOnPragmaMSStruct(PragmaMSStructKind Kind) {
MSStructPragmaOn = (Kind == PMSST_ON);
}
void Sema::ActOnPragmaMSComment(SourceLocation CommentLoc,
PragmaMSCommentKind Kind, StringRef Arg) {
auto *PCD = PragmaCommentDecl::Create(
Context, Context.getTranslationUnitDecl(), CommentLoc, Kind, Arg);
Context.getTranslationUnitDecl()->addDecl(PCD);
Consumer.HandleTopLevelDecl(DeclGroupRef(PCD));
}
void Sema::ActOnPragmaDetectMismatch(SourceLocation Loc, StringRef Name,
StringRef Value) {
auto *PDMD = PragmaDetectMismatchDecl::Create(
Context, Context.getTranslationUnitDecl(), Loc, Name, Value);
Context.getTranslationUnitDecl()->addDecl(PDMD);
Consumer.HandleTopLevelDecl(DeclGroupRef(PDMD));
}
void Sema::ActOnPragmaFloatControl(SourceLocation Loc,
PragmaMsStackAction Action,
PragmaFloatControlKind Value) {
FPOptionsOverride NewFPFeatures = CurFPFeatureOverrides();
if ((Action == PSK_Push_Set || Action == PSK_Push || Action == PSK_Pop) &&
!(CurContext->isTranslationUnit()) && !CurContext->isNamespace()) {
// Push and pop can only occur at file or namespace scope.
Diag(Loc, diag::err_pragma_fc_pp_scope);
return;
}
switch (Value) {
default:
llvm_unreachable("invalid pragma float_control kind");
case PFC_Precise:
NewFPFeatures.setFPPreciseEnabled(true);
FpPragmaStack.Act(Loc, Action, StringRef(), NewFPFeatures);
break;
case PFC_NoPrecise:
if (CurFPFeatures.getFPExceptionMode() == LangOptions::FPE_Strict)
Diag(Loc, diag::err_pragma_fc_noprecise_requires_noexcept);
else if (CurFPFeatures.getAllowFEnvAccess())
Diag(Loc, diag::err_pragma_fc_noprecise_requires_nofenv);
else
NewFPFeatures.setFPPreciseEnabled(false);
FpPragmaStack.Act(Loc, Action, StringRef(), NewFPFeatures);
break;
case PFC_Except:
if (!isPreciseFPEnabled())
Diag(Loc, diag::err_pragma_fc_except_requires_precise);
else
NewFPFeatures.setFPExceptionModeOverride(LangOptions::FPE_Strict);
FpPragmaStack.Act(Loc, Action, StringRef(), NewFPFeatures);
break;
case PFC_NoExcept:
NewFPFeatures.setFPExceptionModeOverride(LangOptions::FPE_Ignore);
FpPragmaStack.Act(Loc, Action, StringRef(), NewFPFeatures);
break;
case PFC_Push:
FpPragmaStack.Act(Loc, Sema::PSK_Push_Set, StringRef(), NewFPFeatures);
break;
case PFC_Pop:
if (FpPragmaStack.Stack.empty()) {
Diag(Loc, diag::warn_pragma_pop_failed) << "float_control"
<< "stack empty";
return;
}
FpPragmaStack.Act(Loc, Action, StringRef(), NewFPFeatures);
NewFPFeatures = FpPragmaStack.CurrentValue;
break;
}
CurFPFeatures = NewFPFeatures.applyOverrides(getLangOpts());
}
void Sema::ActOnPragmaMSPointersToMembers(
LangOptions::PragmaMSPointersToMembersKind RepresentationMethod,
SourceLocation PragmaLoc) {
MSPointerToMemberRepresentationMethod = RepresentationMethod;
ImplicitMSInheritanceAttrLoc = PragmaLoc;
}
void Sema::ActOnPragmaMSVtorDisp(PragmaMsStackAction Action,
SourceLocation PragmaLoc,
MSVtorDispMode Mode) {
if (Action & PSK_Pop && VtorDispStack.Stack.empty())
Diag(PragmaLoc, diag::warn_pragma_pop_failed) << "vtordisp"
<< "stack empty";
VtorDispStack.Act(PragmaLoc, Action, StringRef(), Mode);
}
bool Sema::UnifySection(StringRef SectionName,
int SectionFlags,
DeclaratorDecl *Decl) {
SourceLocation PragmaLocation;
if (auto A = Decl->getAttr<SectionAttr>())
if (A->isImplicit())
PragmaLocation = A->getLocation();
auto SectionIt = Context.SectionInfos.find(SectionName);
if (SectionIt == Context.SectionInfos.end()) {
Context.SectionInfos[SectionName] =
ASTContext::SectionInfo(Decl, PragmaLocation, SectionFlags);
return false;
}
// A pre-declared section takes precedence w/o diagnostic.
const auto &Section = SectionIt->second;
if (Section.SectionFlags == SectionFlags ||
((SectionFlags & ASTContext::PSF_Implicit) &&
!(Section.SectionFlags & ASTContext::PSF_Implicit)))
return false;
Diag(Decl->getLocation(), diag::err_section_conflict) << Decl << Section;
if (Section.Decl)
Diag(Section.Decl->getLocation(), diag::note_declared_at)
<< Section.Decl->getName();
if (PragmaLocation.isValid())
Diag(PragmaLocation, diag::note_pragma_entered_here);
if (Section.PragmaSectionLocation.isValid())
Diag(Section.PragmaSectionLocation, diag::note_pragma_entered_here);
return true;
}
bool Sema::UnifySection(StringRef SectionName,
int SectionFlags,
SourceLocation PragmaSectionLocation) {
auto SectionIt = Context.SectionInfos.find(SectionName);
if (SectionIt != Context.SectionInfos.end()) {
const auto &Section = SectionIt->second;
if (Section.SectionFlags == SectionFlags)
return false;
if (!(Section.SectionFlags & ASTContext::PSF_Implicit)) {
Diag(PragmaSectionLocation, diag::err_section_conflict)
<< "this" << Section;
if (Section.Decl)
Diag(Section.Decl->getLocation(), diag::note_declared_at)
<< Section.Decl->getName();
if (Section.PragmaSectionLocation.isValid())
Diag(Section.PragmaSectionLocation, diag::note_pragma_entered_here);
return true;
}
}
Context.SectionInfos[SectionName] =
ASTContext::SectionInfo(nullptr, PragmaSectionLocation, SectionFlags);
return false;
}
/// Called on well formed \#pragma bss_seg().
void Sema::ActOnPragmaMSSeg(SourceLocation PragmaLocation,
PragmaMsStackAction Action,
llvm::StringRef StackSlotLabel,
StringLiteral *SegmentName,
llvm::StringRef PragmaName) {
PragmaStack<StringLiteral *> *Stack =
llvm::StringSwitch<PragmaStack<StringLiteral *> *>(PragmaName)
.Case("data_seg", &DataSegStack)
.Case("bss_seg", &BSSSegStack)
.Case("const_seg", &ConstSegStack)
.Case("code_seg", &CodeSegStack);
if (Action & PSK_Pop && Stack->Stack.empty())
Diag(PragmaLocation, diag::warn_pragma_pop_failed) << PragmaName
<< "stack empty";
if (SegmentName) {
if (!checkSectionName(SegmentName->getBeginLoc(), SegmentName->getString()))
return;
if (SegmentName->getString() == ".drectve" &&
Context.getTargetInfo().getCXXABI().isMicrosoft())
Diag(PragmaLocation, diag::warn_attribute_section_drectve) << PragmaName;
}
Stack->Act(PragmaLocation, Action, StackSlotLabel, SegmentName);
}
/// Called on well formed \#pragma bss_seg().
void Sema::ActOnPragmaMSSection(SourceLocation PragmaLocation,
int SectionFlags, StringLiteral *SegmentName) {
UnifySection(SegmentName->getString(), SectionFlags, PragmaLocation);
}
void Sema::ActOnPragmaMSInitSeg(SourceLocation PragmaLocation,
StringLiteral *SegmentName) {
// There's no stack to maintain, so we just have a current section. When we
// see the default section, reset our current section back to null so we stop
// tacking on unnecessary attributes.
CurInitSeg = SegmentName->getString() == ".CRT$XCU" ? nullptr : SegmentName;
CurInitSegLoc = PragmaLocation;
}
void Sema::ActOnPragmaUnused(const Token &IdTok, Scope *curScope,
SourceLocation PragmaLoc) {
IdentifierInfo *Name = IdTok.getIdentifierInfo();
LookupResult Lookup(*this, Name, IdTok.getLocation(), LookupOrdinaryName);
LookupParsedName(Lookup, curScope, nullptr, true);
if (Lookup.empty()) {
Diag(PragmaLoc, diag::warn_pragma_unused_undeclared_var)
<< Name << SourceRange(IdTok.getLocation());
return;
}
VarDecl *VD = Lookup.getAsSingle<VarDecl>();
if (!VD) {
Diag(PragmaLoc, diag::warn_pragma_unused_expected_var_arg)
<< Name << SourceRange(IdTok.getLocation());
return;
}
// Warn if this was used before being marked unused.
if (VD->isUsed())
Diag(PragmaLoc, diag::warn_used_but_marked_unused) << Name;
VD->addAttr(UnusedAttr::CreateImplicit(Context, IdTok.getLocation(),
AttributeCommonInfo::AS_Pragma,
UnusedAttr::GNU_unused));
}
void Sema::AddCFAuditedAttribute(Decl *D) {
IdentifierInfo *Ident;
SourceLocation Loc;
std::tie(Ident, Loc) = PP.getPragmaARCCFCodeAuditedInfo();
if (!Loc.isValid()) return;
// Don't add a redundant or conflicting attribute.
if (D->hasAttr<CFAuditedTransferAttr>() ||
D->hasAttr<CFUnknownTransferAttr>())
return;
AttributeCommonInfo Info(Ident, SourceRange(Loc),
AttributeCommonInfo::AS_Pragma);
D->addAttr(CFAuditedTransferAttr::CreateImplicit(Context, Info));
}
namespace {
Optional<attr::SubjectMatchRule>
getParentAttrMatcherRule(attr::SubjectMatchRule Rule) {
using namespace attr;
switch (Rule) {
default:
return None;
#define ATTR_MATCH_RULE(Value, Spelling, IsAbstract)
#define ATTR_MATCH_SUB_RULE(Value, Spelling, IsAbstract, Parent, IsNegated) \
case Value: \
return Parent;
#include "clang/Basic/AttrSubMatchRulesList.inc"
}
}
bool isNegatedAttrMatcherSubRule(attr::SubjectMatchRule Rule) {
using namespace attr;
switch (Rule) {
default:
return false;
#define ATTR_MATCH_RULE(Value, Spelling, IsAbstract)
#define ATTR_MATCH_SUB_RULE(Value, Spelling, IsAbstract, Parent, IsNegated) \
case Value: \
return IsNegated;
#include "clang/Basic/AttrSubMatchRulesList.inc"
}
}
CharSourceRange replacementRangeForListElement(const Sema &S,
SourceRange Range) {
// Make sure that the ',' is removed as well.
SourceLocation AfterCommaLoc = Lexer::findLocationAfterToken(
Range.getEnd(), tok::comma, S.getSourceManager(), S.getLangOpts(),
/*SkipTrailingWhitespaceAndNewLine=*/false);
if (AfterCommaLoc.isValid())
return CharSourceRange::getCharRange(Range.getBegin(), AfterCommaLoc);
else
return CharSourceRange::getTokenRange(Range);
}
std::string
attrMatcherRuleListToString(ArrayRef<attr::SubjectMatchRule> Rules) {
std::string Result;
llvm::raw_string_ostream OS(Result);
for (const auto &I : llvm::enumerate(Rules)) {
if (I.index())
OS << (I.index() == Rules.size() - 1 ? ", and " : ", ");
OS << "'" << attr::getSubjectMatchRuleSpelling(I.value()) << "'";
}
return OS.str();
}
} // end anonymous namespace
void Sema::ActOnPragmaAttributeAttribute(
ParsedAttr &Attribute, SourceLocation PragmaLoc,
attr::ParsedSubjectMatchRuleSet Rules) {
Attribute.setIsPragmaClangAttribute();
SmallVector<attr::SubjectMatchRule, 4> SubjectMatchRules;
// Gather the subject match rules that are supported by the attribute.
SmallVector<std::pair<attr::SubjectMatchRule, bool>, 4>
StrictSubjectMatchRuleSet;
Attribute.getMatchRules(LangOpts, StrictSubjectMatchRuleSet);
// Figure out which subject matching rules are valid.
if (StrictSubjectMatchRuleSet.empty()) {
// Check for contradicting match rules. Contradicting match rules are
// either:
// - a top-level rule and one of its sub-rules. E.g. variable and
// variable(is_parameter).
// - a sub-rule and a sibling that's negated. E.g.
// variable(is_thread_local) and variable(unless(is_parameter))
llvm::SmallDenseMap<int, std::pair<int, SourceRange>, 2>
RulesToFirstSpecifiedNegatedSubRule;
for (const auto &Rule : Rules) {
attr::SubjectMatchRule MatchRule = attr::SubjectMatchRule(Rule.first);
Optional<attr::SubjectMatchRule> ParentRule =
getParentAttrMatcherRule(MatchRule);
if (!ParentRule)
continue;
auto It = Rules.find(*ParentRule);
if (It != Rules.end()) {
// A sub-rule contradicts a parent rule.
Diag(Rule.second.getBegin(),
diag::err_pragma_attribute_matcher_subrule_contradicts_rule)
<< attr::getSubjectMatchRuleSpelling(MatchRule)
<< attr::getSubjectMatchRuleSpelling(*ParentRule) << It->second
<< FixItHint::CreateRemoval(
replacementRangeForListElement(*this, Rule.second));
// Keep going without removing this rule as it won't change the set of
// declarations that receive the attribute.
continue;
}
if (isNegatedAttrMatcherSubRule(MatchRule))
RulesToFirstSpecifiedNegatedSubRule.insert(
std::make_pair(*ParentRule, Rule));
}
bool IgnoreNegatedSubRules = false;
for (const auto &Rule : Rules) {
attr::SubjectMatchRule MatchRule = attr::SubjectMatchRule(Rule.first);
Optional<attr::SubjectMatchRule> ParentRule =
getParentAttrMatcherRule(MatchRule);
if (!ParentRule)
continue;
auto It = RulesToFirstSpecifiedNegatedSubRule.find(*ParentRule);
if (It != RulesToFirstSpecifiedNegatedSubRule.end() &&
It->second != Rule) {
// Negated sub-rule contradicts another sub-rule.
Diag(
It->second.second.getBegin(),
diag::
err_pragma_attribute_matcher_negated_subrule_contradicts_subrule)
<< attr::getSubjectMatchRuleSpelling(
attr::SubjectMatchRule(It->second.first))
<< attr::getSubjectMatchRuleSpelling(MatchRule) << Rule.second
<< FixItHint::CreateRemoval(
replacementRangeForListElement(*this, It->second.second));
// Keep going but ignore all of the negated sub-rules.
IgnoreNegatedSubRules = true;
RulesToFirstSpecifiedNegatedSubRule.erase(It);
}
}
if (!IgnoreNegatedSubRules) {
for (const auto &Rule : Rules)
SubjectMatchRules.push_back(attr::SubjectMatchRule(Rule.first));
} else {
for (const auto &Rule : Rules) {
if (!isNegatedAttrMatcherSubRule(attr::SubjectMatchRule(Rule.first)))
SubjectMatchRules.push_back(attr::SubjectMatchRule(Rule.first));
}
}
Rules.clear();
} else {
for (const auto &Rule : StrictSubjectMatchRuleSet) {
if (Rules.erase(Rule.first)) {
// Add the rule to the set of attribute receivers only if it's supported
// in the current language mode.
if (Rule.second)
SubjectMatchRules.push_back(Rule.first);
}
}
}
if (!Rules.empty()) {
auto Diagnostic =
Diag(PragmaLoc, diag::err_pragma_attribute_invalid_matchers)
<< Attribute;
SmallVector<attr::SubjectMatchRule, 2> ExtraRules;
for (const auto &Rule : Rules) {
ExtraRules.push_back(attr::SubjectMatchRule(Rule.first));
Diagnostic << FixItHint::CreateRemoval(
replacementRangeForListElement(*this, Rule.second));
}
Diagnostic << attrMatcherRuleListToString(ExtraRules);
}
if (PragmaAttributeStack.empty()) {
Diag(PragmaLoc, diag::err_pragma_attr_attr_no_push);
return;
}
PragmaAttributeStack.back().Entries.push_back(
{PragmaLoc, &Attribute, std::move(SubjectMatchRules), /*IsUsed=*/false});
}
void Sema::ActOnPragmaAttributeEmptyPush(SourceLocation PragmaLoc,
const IdentifierInfo *Namespace) {
PragmaAttributeStack.emplace_back();
PragmaAttributeStack.back().Loc = PragmaLoc;
PragmaAttributeStack.back().Namespace = Namespace;
}
void Sema::ActOnPragmaAttributePop(SourceLocation PragmaLoc,
const IdentifierInfo *Namespace) {
if (PragmaAttributeStack.empty()) {
Diag(PragmaLoc, diag::err_pragma_attribute_stack_mismatch) << 1;
return;
}
// Dig back through the stack trying to find the most recently pushed group
// that in Namespace. Note that this works fine if no namespace is present,
// think of push/pops without namespaces as having an implicit "nullptr"
// namespace.
for (size_t Index = PragmaAttributeStack.size(); Index;) {
--Index;
if (PragmaAttributeStack[Index].Namespace == Namespace) {
for (const PragmaAttributeEntry &Entry :
PragmaAttributeStack[Index].Entries) {
if (!Entry.IsUsed) {
assert(Entry.Attribute && "Expected an attribute");
Diag(Entry.Attribute->getLoc(), diag::warn_pragma_attribute_unused)
<< *Entry.Attribute;
Diag(PragmaLoc, diag::note_pragma_attribute_region_ends_here);
}
}
PragmaAttributeStack.erase(PragmaAttributeStack.begin() + Index);
return;
}
}
if (Namespace)
Diag(PragmaLoc, diag::err_pragma_attribute_stack_mismatch)
<< 0 << Namespace->getName();
else
Diag(PragmaLoc, diag::err_pragma_attribute_stack_mismatch) << 1;
}
void Sema::AddPragmaAttributes(Scope *S, Decl *D) {
if (PragmaAttributeStack.empty())
return;
for (auto &Group : PragmaAttributeStack) {
for (auto &Entry : Group.Entries) {
ParsedAttr *Attribute = Entry.Attribute;
assert(Attribute && "Expected an attribute");
assert(Attribute->isPragmaClangAttribute() &&
"expected #pragma clang attribute");
// Ensure that the attribute can be applied to the given declaration.
bool Applies = false;
for (const auto &Rule : Entry.MatchRules) {
if (Attribute->appliesToDecl(D, Rule)) {
Applies = true;
break;
}
}
if (!Applies)
continue;
Entry.IsUsed = true;
PragmaAttributeCurrentTargetDecl = D;
ParsedAttributesView Attrs;
Attrs.addAtEnd(Attribute);
ProcessDeclAttributeList(S, D, Attrs);
PragmaAttributeCurrentTargetDecl = nullptr;
}
}
}
void Sema::PrintPragmaAttributeInstantiationPoint() {
assert(PragmaAttributeCurrentTargetDecl && "Expected an active declaration");
Diags.Report(PragmaAttributeCurrentTargetDecl->getBeginLoc(),
diag::note_pragma_attribute_applied_decl_here);
}
void Sema::DiagnoseUnterminatedPragmaAttribute() {
if (PragmaAttributeStack.empty())
return;
Diag(PragmaAttributeStack.back().Loc, diag::err_pragma_attribute_no_pop_eof);
}
void Sema::ActOnPragmaOptimize(bool On, SourceLocation PragmaLoc) {
if(On)
OptimizeOffPragmaLocation = SourceLocation();
else
OptimizeOffPragmaLocation = PragmaLoc;
}
void Sema::AddRangeBasedOptnone(FunctionDecl *FD) {
// In the future, check other pragmas if they're implemented (e.g. pragma
// optimize 0 will probably map to this functionality too).
if(OptimizeOffPragmaLocation.isValid())
AddOptnoneAttributeIfNoConflicts(FD, OptimizeOffPragmaLocation);
}
void Sema::AddOptnoneAttributeIfNoConflicts(FunctionDecl *FD,
SourceLocation Loc) {
// Don't add a conflicting attribute. No diagnostic is needed.
if (FD->hasAttr<MinSizeAttr>() || FD->hasAttr<AlwaysInlineAttr>())
return;
// Add attributes only if required. Optnone requires noinline as well, but if
// either is already present then don't bother adding them.
if (!FD->hasAttr<OptimizeNoneAttr>())
FD->addAttr(OptimizeNoneAttr::CreateImplicit(Context, Loc));
if (!FD->hasAttr<NoInlineAttr>())
FD->addAttr(NoInlineAttr::CreateImplicit(Context, Loc));
}
typedef std::vector<std::pair<unsigned, SourceLocation> > VisStack;
enum : unsigned { NoVisibility = ~0U };
void Sema::AddPushedVisibilityAttribute(Decl *D) {
if (!VisContext)
return;
NamedDecl *ND = dyn_cast<NamedDecl>(D);
if (ND && ND->getExplicitVisibility(NamedDecl::VisibilityForValue))
return;
VisStack *Stack = static_cast<VisStack*>(VisContext);
unsigned rawType = Stack->back().first;
if (rawType == NoVisibility) return;
VisibilityAttr::VisibilityType type
= (VisibilityAttr::VisibilityType) rawType;
SourceLocation loc = Stack->back().second;
D->addAttr(VisibilityAttr::CreateImplicit(Context, type, loc));
}
/// FreeVisContext - Deallocate and null out VisContext.
void Sema::FreeVisContext() {
delete static_cast<VisStack*>(VisContext);
VisContext = nullptr;
}
static void PushPragmaVisibility(Sema &S, unsigned type, SourceLocation loc) {
// Put visibility on stack.
if (!S.VisContext)
S.VisContext = new VisStack;
VisStack *Stack = static_cast<VisStack*>(S.VisContext);
Stack->push_back(std::make_pair(type, loc));
}
void Sema::ActOnPragmaVisibility(const IdentifierInfo* VisType,
SourceLocation PragmaLoc) {
if (VisType) {
// Compute visibility to use.
VisibilityAttr::VisibilityType T;
if (!VisibilityAttr::ConvertStrToVisibilityType(VisType->getName(), T)) {
Diag(PragmaLoc, diag::warn_attribute_unknown_visibility) << VisType;
return;
}
PushPragmaVisibility(*this, T, PragmaLoc);
} else {
PopPragmaVisibility(false, PragmaLoc);
}
}
void Sema::ActOnPragmaFPContract(SourceLocation Loc,
LangOptions::FPModeKind FPC) {
FPOptionsOverride NewFPFeatures = CurFPFeatureOverrides();
switch (FPC) {
case LangOptions::FPM_On:
NewFPFeatures.setAllowFPContractWithinStatement();
break;
case LangOptions::FPM_Fast:
NewFPFeatures.setAllowFPContractAcrossStatement();
break;
case LangOptions::FPM_Off:
NewFPFeatures.setDisallowFPContract();
break;
case LangOptions::FPM_FastHonorPragmas:
llvm_unreachable("Should not happen");
}
FpPragmaStack.Act(Loc, Sema::PSK_Set, StringRef(), NewFPFeatures);
CurFPFeatures = NewFPFeatures.applyOverrides(getLangOpts());
}
void Sema::ActOnPragmaFPReassociate(SourceLocation Loc, bool IsEnabled) {
FPOptionsOverride NewFPFeatures = CurFPFeatureOverrides();
NewFPFeatures.setAllowFPReassociateOverride(IsEnabled);
FpPragmaStack.Act(Loc, PSK_Set, StringRef(), NewFPFeatures);
CurFPFeatures = NewFPFeatures.applyOverrides(getLangOpts());
}
void Sema::setRoundingMode(SourceLocation Loc, llvm::RoundingMode FPR) {
// C2x: 7.6.2p3 If the FE_DYNAMIC mode is specified and FENV_ACCESS is "off",
// the translator may assume that the default rounding mode is in effect.
if (FPR == llvm::RoundingMode::Dynamic &&
!CurFPFeatures.getAllowFEnvAccess() &&
CurFPFeatures.getFPExceptionMode() == LangOptions::FPE_Ignore)
FPR = llvm::RoundingMode::NearestTiesToEven;
FPOptionsOverride NewFPFeatures = CurFPFeatureOverrides();
NewFPFeatures.setRoundingModeOverride(FPR);
FpPragmaStack.Act(Loc, PSK_Set, StringRef(), NewFPFeatures);
CurFPFeatures = NewFPFeatures.applyOverrides(getLangOpts());
}
void Sema::setExceptionMode(SourceLocation Loc,
LangOptions::FPExceptionModeKind FPE) {
FPOptionsOverride NewFPFeatures = CurFPFeatureOverrides();
NewFPFeatures.setFPExceptionModeOverride(FPE);
FpPragmaStack.Act(Loc, PSK_Set, StringRef(), NewFPFeatures);
CurFPFeatures = NewFPFeatures.applyOverrides(getLangOpts());
}
void Sema::ActOnPragmaFEnvAccess(SourceLocation Loc, bool IsEnabled) {
FPOptionsOverride NewFPFeatures = CurFPFeatureOverrides();
auto LO = getLangOpts();
if (IsEnabled) {
// Verify Microsoft restriction:
// You can't enable fenv_access unless precise semantics are enabled.
// Precise semantics can be enabled either by the float_control
// pragma, or by using the /fp:precise or /fp:strict compiler options
if (!isPreciseFPEnabled())
Diag(Loc, diag::err_pragma_fenv_requires_precise);
NewFPFeatures.setAllowFEnvAccessOverride(true);
// Enabling FENV access sets the RoundingMode to Dynamic.
// and ExceptionBehavior to Strict
NewFPFeatures.setRoundingModeOverride(llvm::RoundingMode::Dynamic);
NewFPFeatures.setFPExceptionModeOverride(LangOptions::FPE_Strict);
} else {
NewFPFeatures.setAllowFEnvAccessOverride(false);
}
FpPragmaStack.Act(Loc, PSK_Set, StringRef(), NewFPFeatures);
CurFPFeatures = NewFPFeatures.applyOverrides(LO);
}
void Sema::ActOnPragmaFPExceptions(SourceLocation Loc,
LangOptions::FPExceptionModeKind FPE) {
setExceptionMode(Loc, FPE);
}
void Sema::PushNamespaceVisibilityAttr(const VisibilityAttr *Attr,
SourceLocation Loc) {
// Visibility calculations will consider the namespace's visibility.
// Here we just want to note that we're in a visibility context
// which overrides any enclosing #pragma context, but doesn't itself
// contribute visibility.
PushPragmaVisibility(*this, NoVisibility, Loc);
}
void Sema::PopPragmaVisibility(bool IsNamespaceEnd, SourceLocation EndLoc) {
if (!VisContext) {
Diag(EndLoc, diag::err_pragma_pop_visibility_mismatch);
return;
}
// Pop visibility from stack
VisStack *Stack = static_cast<VisStack*>(VisContext);
const std::pair<unsigned, SourceLocation> *Back = &Stack->back();
bool StartsWithPragma = Back->first != NoVisibility;
if (StartsWithPragma && IsNamespaceEnd) {
Diag(Back->second, diag::err_pragma_push_visibility_mismatch);
Diag(EndLoc, diag::note_surrounding_namespace_ends_here);
// For better error recovery, eat all pushes inside the namespace.
do {
Stack->pop_back();
Back = &Stack->back();
StartsWithPragma = Back->first != NoVisibility;
} while (StartsWithPragma);
} else if (!StartsWithPragma && !IsNamespaceEnd) {
Diag(EndLoc, diag::err_pragma_pop_visibility_mismatch);
Diag(Back->second, diag::note_surrounding_namespace_starts_here);
return;
}
Stack->pop_back();
// To simplify the implementation, never keep around an empty stack.
if (Stack->empty())
FreeVisContext();
}