diff options
Diffstat (limited to 'contrib/llvm/tools/clang/lib/Sema/ScopeInfo.cpp')
-rw-r--r-- | contrib/llvm/tools/clang/lib/Sema/ScopeInfo.cpp | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/contrib/llvm/tools/clang/lib/Sema/ScopeInfo.cpp b/contrib/llvm/tools/clang/lib/Sema/ScopeInfo.cpp new file mode 100644 index 0000000..8b3493e --- /dev/null +++ b/contrib/llvm/tools/clang/lib/Sema/ScopeInfo.cpp @@ -0,0 +1,205 @@ +//===--- ScopeInfo.cpp - Information about a semantic context -------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements FunctionScopeInfo and its subclasses, which contain +// information about a single function, block, lambda, or method body. +// +//===----------------------------------------------------------------------===// + +#include "clang/Sema/ScopeInfo.h" +#include "clang/AST/Decl.h" +#include "clang/AST/DeclObjC.h" +#include "clang/AST/Expr.h" +#include "clang/AST/ExprCXX.h" +#include "clang/AST/ExprObjC.h" + +using namespace clang; +using namespace sema; + +void FunctionScopeInfo::Clear() { + HasBranchProtectedScope = false; + HasBranchIntoScope = false; + HasIndirectGoto = false; + + SwitchStack.clear(); + Returns.clear(); + ErrorTrap.reset(); + PossiblyUnreachableDiags.clear(); + WeakObjectUses.clear(); +} + +static const NamedDecl *getBestPropertyDecl(const ObjCPropertyRefExpr *PropE) { + if (PropE->isExplicitProperty()) + return PropE->getExplicitProperty(); + + return PropE->getImplicitPropertyGetter(); +} + +FunctionScopeInfo::WeakObjectProfileTy::BaseInfoTy +FunctionScopeInfo::WeakObjectProfileTy::getBaseInfo(const Expr *E) { + E = E->IgnoreParenCasts(); + + const NamedDecl *D = 0; + bool IsExact = false; + + switch (E->getStmtClass()) { + case Stmt::DeclRefExprClass: + D = cast<DeclRefExpr>(E)->getDecl(); + IsExact = isa<VarDecl>(D); + break; + case Stmt::MemberExprClass: { + const MemberExpr *ME = cast<MemberExpr>(E); + D = ME->getMemberDecl(); + IsExact = isa<CXXThisExpr>(ME->getBase()->IgnoreParenImpCasts()); + break; + } + case Stmt::ObjCIvarRefExprClass: { + const ObjCIvarRefExpr *IE = cast<ObjCIvarRefExpr>(E); + D = IE->getDecl(); + IsExact = IE->getBase()->isObjCSelfExpr(); + break; + } + case Stmt::PseudoObjectExprClass: { + const PseudoObjectExpr *POE = cast<PseudoObjectExpr>(E); + const ObjCPropertyRefExpr *BaseProp = + dyn_cast<ObjCPropertyRefExpr>(POE->getSyntacticForm()); + if (BaseProp) { + D = getBestPropertyDecl(BaseProp); + + const Expr *DoubleBase = BaseProp->getBase(); + if (const OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(DoubleBase)) + DoubleBase = OVE->getSourceExpr(); + + IsExact = DoubleBase->isObjCSelfExpr(); + } + break; + } + default: + break; + } + + return BaseInfoTy(D, IsExact); +} + + +FunctionScopeInfo::WeakObjectProfileTy::WeakObjectProfileTy( + const ObjCPropertyRefExpr *PropE) + : Base(0, true), Property(getBestPropertyDecl(PropE)) { + + if (PropE->isObjectReceiver()) { + const OpaqueValueExpr *OVE = cast<OpaqueValueExpr>(PropE->getBase()); + const Expr *E = OVE->getSourceExpr(); + Base = getBaseInfo(E); + } else if (PropE->isClassReceiver()) { + Base.setPointer(PropE->getClassReceiver()); + } else { + assert(PropE->isSuperReceiver()); + } +} + +FunctionScopeInfo::WeakObjectProfileTy::WeakObjectProfileTy(const Expr *BaseE, + const ObjCPropertyDecl *Prop) + : Base(0, true), Property(Prop) { + if (BaseE) + Base = getBaseInfo(BaseE); + // else, this is a message accessing a property on super. +} + +FunctionScopeInfo::WeakObjectProfileTy::WeakObjectProfileTy( + const DeclRefExpr *DRE) + : Base(0, true), Property(DRE->getDecl()) { + assert(isa<VarDecl>(Property)); +} + +FunctionScopeInfo::WeakObjectProfileTy::WeakObjectProfileTy( + const ObjCIvarRefExpr *IvarE) + : Base(getBaseInfo(IvarE->getBase())), Property(IvarE->getDecl()) { +} + +void FunctionScopeInfo::recordUseOfWeak(const ObjCMessageExpr *Msg, + const ObjCPropertyDecl *Prop) { + assert(Msg && Prop); + WeakUseVector &Uses = + WeakObjectUses[WeakObjectProfileTy(Msg->getInstanceReceiver(), Prop)]; + Uses.push_back(WeakUseTy(Msg, Msg->getNumArgs() == 0)); +} + +void FunctionScopeInfo::markSafeWeakUse(const Expr *E) { + E = E->IgnoreParenCasts(); + + if (const PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E)) { + markSafeWeakUse(POE->getSyntacticForm()); + return; + } + + if (const ConditionalOperator *Cond = dyn_cast<ConditionalOperator>(E)) { + markSafeWeakUse(Cond->getTrueExpr()); + markSafeWeakUse(Cond->getFalseExpr()); + return; + } + + if (const BinaryConditionalOperator *Cond = + dyn_cast<BinaryConditionalOperator>(E)) { + markSafeWeakUse(Cond->getCommon()); + markSafeWeakUse(Cond->getFalseExpr()); + return; + } + + // Has this weak object been seen before? + FunctionScopeInfo::WeakObjectUseMap::iterator Uses; + if (const ObjCPropertyRefExpr *RefExpr = dyn_cast<ObjCPropertyRefExpr>(E)) + Uses = WeakObjectUses.find(WeakObjectProfileTy(RefExpr)); + else if (const ObjCIvarRefExpr *IvarE = dyn_cast<ObjCIvarRefExpr>(E)) + Uses = WeakObjectUses.find(WeakObjectProfileTy(IvarE)); + else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) + Uses = WeakObjectUses.find(WeakObjectProfileTy(DRE)); + else if (const ObjCMessageExpr *MsgE = dyn_cast<ObjCMessageExpr>(E)) { + Uses = WeakObjectUses.end(); + if (const ObjCMethodDecl *MD = MsgE->getMethodDecl()) { + if (const ObjCPropertyDecl *Prop = MD->findPropertyDecl()) { + Uses = + WeakObjectUses.find(WeakObjectProfileTy(MsgE->getInstanceReceiver(), + Prop)); + } + } + } + else + return; + + if (Uses == WeakObjectUses.end()) + return; + + // Has there been a read from the object using this Expr? + FunctionScopeInfo::WeakUseVector::reverse_iterator ThisUse = + std::find(Uses->second.rbegin(), Uses->second.rend(), WeakUseTy(E, true)); + if (ThisUse == Uses->second.rend()) + return; + + ThisUse->markSafe(); +} + +void LambdaScopeInfo::getPotentialVariableCapture(unsigned Idx, VarDecl *&VD, Expr *&E) { + assert(Idx < getNumPotentialVariableCaptures() && + "Index of potential capture must be within 0 to less than the " + "number of captures!"); + E = PotentiallyCapturingExprs[Idx]; + if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) + VD = dyn_cast<VarDecl>(DRE->getFoundDecl()); + else if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) + VD = dyn_cast<VarDecl>(ME->getMemberDecl()); + else + llvm_unreachable("Only DeclRefExprs or MemberExprs should be added for " + "potential captures"); + assert(VD); +} + +FunctionScopeInfo::~FunctionScopeInfo() { } +BlockScopeInfo::~BlockScopeInfo() { } +LambdaScopeInfo::~LambdaScopeInfo() { } +CapturedRegionScopeInfo::~CapturedRegionScopeInfo() { } |