llvm-project/clang/lib/Sema/SemaStmtAttr.cpp

234 lines
8.4 KiB
C++

//===--- SemaStmtAttr.cpp - Statement Attribute Handling ------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements stmt-related attribute processing.
//
//===----------------------------------------------------------------------===//
#include "clang/Sema/SemaInternal.h"
#include "clang/AST/ASTContext.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Sema/DelayedDiagnostic.h"
#include "clang/Sema/Lookup.h"
#include "clang/Sema/LoopHint.h"
#include "clang/Sema/ScopeInfo.h"
#include "llvm/ADT/StringExtras.h"
using namespace clang;
using namespace sema;
static Attr *handleFallThroughAttr(Sema &S, Stmt *St, const AttributeList &A,
SourceRange Range) {
if (!isa<NullStmt>(St)) {
S.Diag(A.getRange().getBegin(), diag::err_fallthrough_attr_wrong_target)
<< St->getLocStart();
if (isa<SwitchCase>(St)) {
SourceLocation L = S.getLocForEndOfToken(Range.getEnd());
S.Diag(L, diag::note_fallthrough_insert_semi_fixit)
<< FixItHint::CreateInsertion(L, ";");
}
return nullptr;
}
if (S.getCurFunction()->SwitchStack.empty()) {
S.Diag(A.getRange().getBegin(), diag::err_fallthrough_attr_outside_switch);
return nullptr;
}
return ::new (S.Context) FallThroughAttr(A.getRange(), S.Context,
A.getAttributeSpellingListIndex());
}
static Attr *handleLoopHintAttr(Sema &S, Stmt *St, const AttributeList &A,
SourceRange) {
if (St->getStmtClass() != Stmt::DoStmtClass &&
St->getStmtClass() != Stmt::ForStmtClass &&
St->getStmtClass() != Stmt::CXXForRangeStmtClass &&
St->getStmtClass() != Stmt::WhileStmtClass) {
S.Diag(St->getLocStart(), diag::err_pragma_loop_precedes_nonloop);
return nullptr;
}
IdentifierLoc *OptionLoc = A.getArgAsIdent(0);
IdentifierInfo *OptionInfo = OptionLoc->Ident;
IdentifierLoc *ValueLoc = A.getArgAsIdent(1);
IdentifierInfo *ValueInfo = ValueLoc->Ident;
Expr *ValueExpr = A.getArgAsExpr(2);
assert(OptionInfo && "Attribute must have valid option info.");
LoopHintAttr::OptionType Option =
llvm::StringSwitch<LoopHintAttr::OptionType>(OptionInfo->getName())
.Case("vectorize", LoopHintAttr::Vectorize)
.Case("vectorize_width", LoopHintAttr::VectorizeWidth)
.Case("interleave", LoopHintAttr::Interleave)
.Case("interleave_count", LoopHintAttr::InterleaveCount)
.Default(LoopHintAttr::Vectorize);
int ValueInt;
if (Option == LoopHintAttr::Vectorize || Option == LoopHintAttr::Interleave) {
if (!ValueInfo) {
S.Diag(ValueLoc->Loc, diag::err_pragma_loop_invalid_keyword)
<< /*MissingKeyword=*/true << "";
return nullptr;
}
if (ValueInfo->isStr("disable"))
ValueInt = 0;
else if (ValueInfo->isStr("enable"))
ValueInt = 1;
else {
S.Diag(ValueLoc->Loc, diag::err_pragma_loop_invalid_keyword)
<< /*MissingKeyword=*/false << ValueInfo;
return nullptr;
}
} else if (Option == LoopHintAttr::VectorizeWidth ||
Option == LoopHintAttr::InterleaveCount) {
// FIXME: We should support template parameters for the loop hint value.
// See bug report #19610.
llvm::APSInt ValueAPS;
if (!ValueExpr || !ValueExpr->isIntegerConstantExpr(ValueAPS, S.Context)) {
S.Diag(ValueLoc->Loc, diag::err_pragma_loop_invalid_value)
<< /*MissingValue=*/true << "";
return nullptr;
}
if ((ValueInt = ValueAPS.getSExtValue()) < 1) {
S.Diag(ValueLoc->Loc, diag::err_pragma_loop_invalid_value)
<< /*MissingValue=*/false << ValueInt;
return nullptr;
}
} else
llvm_unreachable("Unknown loop hint option");
return LoopHintAttr::CreateImplicit(S.Context, Option, ValueInt,
A.getRange());
}
static void
CheckForIncompatibleAttributes(Sema &S, SmallVectorImpl<const Attr *> &Attrs) {
int PrevOptionValue[4] = {-1, -1, -1, -1};
int OptionId[4] = {LoopHintAttr::Vectorize, LoopHintAttr::VectorizeWidth,
LoopHintAttr::Interleave, LoopHintAttr::InterleaveCount};
for (const auto *I : Attrs) {
const LoopHintAttr *LH = dyn_cast<LoopHintAttr>(I);
// Skip non loop hint attributes
if (!LH)
continue;
int State, Value;
int Option = LH->getOption();
int ValueInt = LH->getValue();
switch (Option) {
case LoopHintAttr::Vectorize:
case LoopHintAttr::VectorizeWidth:
State = 0;
Value = 1;
break;
case LoopHintAttr::Interleave:
case LoopHintAttr::InterleaveCount:
State = 2;
Value = 3;
break;
}
SourceLocation ValueLoc = LH->getRange().getEnd();
// Compatibility testing is split into two cases.
// 1. if the current loop hint sets state (enable/disable) - check against
// previous state and value.
// 2. if the current loop hint sets a value - check against previous state
// and value.
if (Option == State) {
if (PrevOptionValue[State] != -1) {
// Cannot specify state twice.
int PrevValue = PrevOptionValue[State];
S.Diag(ValueLoc, diag::err_pragma_loop_compatibility)
<< /*Duplicate=*/true << LoopHintAttr::getOptionName(Option)
<< LoopHintAttr::getValueName(PrevValue)
<< LoopHintAttr::getOptionName(Option)
<< LoopHintAttr::getValueName(Value);
}
if (PrevOptionValue[Value] != -1) {
// Compare state with previous width/count.
int PrevOption = OptionId[Value];
int PrevValueInt = PrevOptionValue[Value];
if ((ValueInt == 0 && PrevValueInt > 1) ||
(ValueInt == 1 && PrevValueInt <= 1))
S.Diag(ValueLoc, diag::err_pragma_loop_compatibility)
<< /*Duplicate=*/false << LoopHintAttr::getOptionName(PrevOption)
<< PrevValueInt << LoopHintAttr::getOptionName(Option)
<< LoopHintAttr::getValueName(ValueInt);
}
} else {
if (PrevOptionValue[State] != -1) {
// Compare width/count value with previous state.
int PrevOption = OptionId[State];
int PrevValueInt = PrevOptionValue[State];
if ((ValueInt > 1 && PrevValueInt == 0) ||
(ValueInt <= 1 && PrevValueInt == 1))
S.Diag(ValueLoc, diag::err_pragma_loop_compatibility)
<< /*Duplicate=*/false << LoopHintAttr::getOptionName(PrevOption)
<< LoopHintAttr::getValueName(PrevValueInt)
<< LoopHintAttr::getOptionName(Option) << ValueInt;
}
if (PrevOptionValue[Value] != -1) {
// Cannot specify a width/count twice.
int PrevValueInt = PrevOptionValue[Value];
S.Diag(ValueLoc, diag::err_pragma_loop_compatibility)
<< /*Duplicate=*/true << LoopHintAttr::getOptionName(Option)
<< PrevValueInt << LoopHintAttr::getOptionName(Option) << ValueInt;
}
}
PrevOptionValue[Option] = ValueInt;
}
}
static Attr *ProcessStmtAttribute(Sema &S, Stmt *St, const AttributeList &A,
SourceRange Range) {
switch (A.getKind()) {
case AttributeList::UnknownAttribute:
S.Diag(A.getLoc(), A.isDeclspecAttribute() ?
diag::warn_unhandled_ms_attribute_ignored :
diag::warn_unknown_attribute_ignored) << A.getName();
return nullptr;
case AttributeList::AT_FallThrough:
return handleFallThroughAttr(S, St, A, Range);
case AttributeList::AT_LoopHint:
return handleLoopHintAttr(S, St, A, Range);
default:
// if we're here, then we parsed a known attribute, but didn't recognize
// it as a statement attribute => it is declaration attribute
S.Diag(A.getRange().getBegin(), diag::err_attribute_invalid_on_stmt)
<< A.getName() << St->getLocStart();
return nullptr;
}
}
StmtResult Sema::ProcessStmtAttributes(Stmt *S, AttributeList *AttrList,
SourceRange Range) {
SmallVector<const Attr*, 8> Attrs;
for (const AttributeList* l = AttrList; l; l = l->getNext()) {
if (Attr *a = ProcessStmtAttribute(*this, S, *l, Range))
Attrs.push_back(a);
}
CheckForIncompatibleAttributes(*this, Attrs);
if (Attrs.empty())
return S;
return ActOnAttributedStmt(Range.getBegin(), Attrs, S);
}