#include "clang/AST/EvaluatedExprVisitor.h"
#include "clang/AST/RecordLayout.h"
#include "clang/AST/StmtCXX.h"
+#include "clang/Basic/TargetBuiltins.h"
#include "clang/Frontend/CodeGenOptions.h"
using namespace clang;
ExitCXXTryStmt(*cast<CXXTryStmt>(Body), true);
}
+namespace {
+ class FieldMemcpyizer {
+ public:
+ FieldMemcpyizer(CodeGenFunction &CGF, const CXXRecordDecl *ClassDecl,
+ const VarDecl *SrcRec)
+ : CGF(CGF), ClassDecl(ClassDecl), SrcRec(SrcRec),
+ RecLayout(CGF.getContext().getASTRecordLayout(ClassDecl)),
+ FirstField(0), LastField(0), FirstFieldOffset(0), LastFieldOffset(0),
+ LastAddedFieldIndex(0) { }
+
+ static bool isMemcpyableField(FieldDecl *F) {
+ Qualifiers Qual = F->getType().getQualifiers();
+ if (Qual.hasVolatile() || Qual.hasObjCLifetime())
+ return false;
+ return true;
+ }
+
+ void addMemcpyableField(FieldDecl *F) {
+ if (FirstField == 0)
+ addInitialField(F);
+ else
+ addNextField(F);
+ }
+
+ CharUnits getMemcpySize() const {
+ unsigned LastFieldSize =
+ CGF.getContext().getTypeInfo(LastField->getType()).first;
+ uint64_t MemcpySizeBits =
+ LastFieldOffset + LastFieldSize - FirstFieldOffset +
+ CGF.getContext().getCharWidth() - 1;
+ CharUnits MemcpySize =
+ CGF.getContext().toCharUnitsFromBits(MemcpySizeBits);
+ return MemcpySize;
+ }
+
+ void emitMemcpy() {
+ // Give the subclass a chance to bail out if it feels the memcpy isn't
+ // worth it (e.g. Hasn't aggregated enough data).
+ if (FirstField == 0) {
+ return;
+ }
+
+ unsigned FirstFieldAlign =
+ CGF.getContext().getTypeInfo(FirstField->getType()).second;
+ assert(FirstFieldOffset % FirstFieldAlign == 0 && "Bad field alignment.");
+ CharUnits Alignment =
+ CGF.getContext().toCharUnitsFromBits(FirstFieldAlign);
+ CharUnits MemcpySize = getMemcpySize();
+ QualType RecordTy = CGF.getContext().getTypeDeclType(ClassDecl);
+ llvm::Value *ThisPtr = CGF.LoadCXXThis();
+ LValue DestLV = CGF.MakeNaturalAlignAddrLValue(ThisPtr, RecordTy);
+ LValue Dest = CGF.EmitLValueForFieldInitialization(DestLV, FirstField);
+ llvm::Value *SrcPtr = CGF.Builder.CreateLoad(CGF.GetAddrOfLocalVar(SrcRec));
+ LValue SrcLV = CGF.MakeNaturalAlignAddrLValue(SrcPtr, RecordTy);
+ LValue Src = CGF.EmitLValueForFieldInitialization(SrcLV, FirstField);
+
+ emitMemcpyIR(Dest.isBitField() ? Dest.getBitFieldAddr() : Dest.getAddress(),
+ Src.isBitField() ? Src.getBitFieldAddr() : Src.getAddress(),
+ MemcpySize, Alignment);
+ reset();
+ }
+
+ void reset() {
+ FirstField = 0;
+ }
+
+ protected:
+ CodeGenFunction &CGF;
+ const CXXRecordDecl *ClassDecl;
+
+ private:
+
+ void emitMemcpyIR(llvm::Value *DestPtr, llvm::Value *SrcPtr,
+ CharUnits Size, CharUnits Alignment) {
+ llvm::PointerType *DPT = cast<llvm::PointerType>(DestPtr->getType());
+ llvm::Type *DBP =
+ llvm::Type::getInt8PtrTy(CGF.getLLVMContext(), DPT->getAddressSpace());
+ DestPtr = CGF.Builder.CreateBitCast(DestPtr, DBP);
+
+ llvm::PointerType *SPT = cast<llvm::PointerType>(SrcPtr->getType());
+ llvm::Type *SBP =
+ llvm::Type::getInt8PtrTy(CGF.getLLVMContext(), SPT->getAddressSpace());
+ SrcPtr = CGF.Builder.CreateBitCast(SrcPtr, SBP);
+
+ CGF.Builder.CreateMemCpy(DestPtr, SrcPtr, Size.getQuantity(),
+ Alignment.getQuantity());
+ }
+
+ void addInitialField(FieldDecl *F) {
+ FirstField = F;
+ LastField = F;
+ FirstFieldOffset = RecLayout.getFieldOffset(F->getFieldIndex());
+ LastFieldOffset = FirstFieldOffset;
+ LastAddedFieldIndex = F->getFieldIndex();
+ return;
+ }
+
+ void addNextField(FieldDecl *F) {
+ assert(F->getFieldIndex() == LastAddedFieldIndex + 1 &&
+ "Cannot aggregate non-contiguous fields.");
+ LastAddedFieldIndex = F->getFieldIndex();
+
+ // The 'first' and 'last' fields are chosen by offset, rather than field
+ // index. This allows the code to support bitfields, as well as regular
+ // fields.
+ uint64_t FOffset = RecLayout.getFieldOffset(F->getFieldIndex());
+ if (FOffset < FirstFieldOffset) {
+ FirstField = F;
+ FirstFieldOffset = FOffset;
+ } else if (FOffset > LastFieldOffset) {
+ LastField = F;
+ LastFieldOffset = FOffset;
+ }
+ }
+
+ const VarDecl *SrcRec;
+ const ASTRecordLayout &RecLayout;
+ FieldDecl *FirstField;
+ FieldDecl *LastField;
+ uint64_t FirstFieldOffset, LastFieldOffset;
+ unsigned LastAddedFieldIndex;
+ };
+
+ class ConstructorMemcpyizer : public FieldMemcpyizer {
+ private:
+
+ /// Get source argument for copy constructor. Returns null if not a copy
+ /// constructor.
+ static const VarDecl* getTrivialCopySource(const CXXConstructorDecl *CD,
+ FunctionArgList &Args) {
+ if (CD->isCopyOrMoveConstructor() && CD->isImplicitlyDefined())
+ return Args[Args.size() - 1];
+ return 0;
+ }
+
+ // Returns true if a CXXCtorInitializer represents a member initialization
+ // that can be rolled into a memcpy.
+ bool isMemberInitMemcpyable(CXXCtorInitializer *MemberInit) const {
+ if (!MemcpyableCtor)
+ return false;
+ FieldDecl *Field = MemberInit->getMember();
+ assert(Field != 0 && "No field for member init.");
+ QualType FieldType = Field->getType();
+ CXXConstructExpr *CE = dyn_cast<CXXConstructExpr>(MemberInit->getInit());
+
+ // Bail out on non-POD, not-trivially-constructable members.
+ if (!(CE && CE->getConstructor()->isTrivial()) &&
+ !(FieldType.isTriviallyCopyableType(CGF.getContext()) ||
+ FieldType->isReferenceType()))
+ return false;
+
+ // Bail out on volatile fields.
+ if (!isMemcpyableField(Field))
+ return false;
+
+ // Otherwise we're good.
+ return true;
+ }
+
+ public:
+ ConstructorMemcpyizer(CodeGenFunction &CGF, const CXXConstructorDecl *CD,
+ FunctionArgList &Args)
+ : FieldMemcpyizer(CGF, CD->getParent(), getTrivialCopySource(CD, Args)),
+ ConstructorDecl(CD),
+ MemcpyableCtor(CD->isImplicitlyDefined() &&
+ CD->isCopyOrMoveConstructor() &&
+ CGF.getLangOpts().getGC() == LangOptions::NonGC),
+ Args(Args) { }
+
+ void addMemberInitializer(CXXCtorInitializer *MemberInit) {
+ if (isMemberInitMemcpyable(MemberInit)) {
+ AggregatedInits.push_back(MemberInit);
+ addMemcpyableField(MemberInit->getMember());
+ } else {
+ emitAggregatedInits();
+ EmitMemberInitializer(CGF, ConstructorDecl->getParent(), MemberInit,
+ ConstructorDecl, Args);
+ }
+ }
+
+ void emitAggregatedInits() {
+ if (AggregatedInits.size() <= 1) {
+ // This memcpy is too small to be worthwhile. Fall back on default
+ // codegen.
+ for (unsigned i = 0; i < AggregatedInits.size(); ++i) {
+ EmitMemberInitializer(CGF, ConstructorDecl->getParent(),
+ AggregatedInits[i], ConstructorDecl, Args);
+ }
+ reset();
+ return;
+ }
+
+ pushEHDestructors();
+ emitMemcpy();
+ AggregatedInits.clear();
+ }
+
+ void pushEHDestructors() {
+ llvm::Value *ThisPtr = CGF.LoadCXXThis();
+ QualType RecordTy = CGF.getContext().getTypeDeclType(ClassDecl);
+ LValue LHS = CGF.MakeNaturalAlignAddrLValue(ThisPtr, RecordTy);
+
+ for (unsigned i = 0; i < AggregatedInits.size(); ++i) {
+ QualType FieldType = AggregatedInits[i]->getMember()->getType();
+ QualType::DestructionKind dtorKind = FieldType.isDestructedType();
+ if (CGF.needsEHCleanup(dtorKind))
+ CGF.pushEHDestroy(dtorKind, LHS.getAddress(), FieldType);
+ }
+ }
+
+ void finish() {
+ emitAggregatedInits();
+ }
+
+ private:
+ const CXXConstructorDecl *ConstructorDecl;
+ bool MemcpyableCtor;
+ FunctionArgList &Args;
+ SmallVector<CXXCtorInitializer*, 16> AggregatedInits;
+ };
+
+ class AssignmentMemcpyizer : public FieldMemcpyizer {
+ private:
+
+ // Returns the memcpyable field copied by the given statement, if one
+ // exists. Otherwise r
+ FieldDecl* getMemcpyableField(Stmt *S) {
+ if (!AssignmentsMemcpyable)
+ return 0;
+ if (BinaryOperator *BO = dyn_cast<BinaryOperator>(S)) {
+ // Recognise trivial assignments.
+ if (BO->getOpcode() != BO_Assign)
+ return 0;
+ MemberExpr *ME = dyn_cast<MemberExpr>(BO->getLHS());
+ if (!ME)
+ return 0;
+ FieldDecl *Field = dyn_cast<FieldDecl>(ME->getMemberDecl());
+ if (!Field || !isMemcpyableField(Field))
+ return 0;
+ Stmt *RHS = BO->getRHS();
+ if (ImplicitCastExpr *EC = dyn_cast<ImplicitCastExpr>(RHS))
+ RHS = EC->getSubExpr();
+ if (!RHS)
+ return 0;
+ MemberExpr *ME2 = dyn_cast<MemberExpr>(RHS);
+ if (dyn_cast<FieldDecl>(ME2->getMemberDecl()) != Field)
+ return 0;
+ return Field;
+ } else if (CXXMemberCallExpr *MCE = dyn_cast<CXXMemberCallExpr>(S)) {
+ CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MCE->getCalleeDecl());
+ if (!(MD && (MD->isCopyAssignmentOperator() ||
+ MD->isMoveAssignmentOperator()) &&
+ MD->isTrivial()))
+ return 0;
+ MemberExpr *IOA = dyn_cast<MemberExpr>(MCE->getImplicitObjectArgument());
+ if (!IOA)
+ return 0;
+ FieldDecl *Field = dyn_cast<FieldDecl>(IOA->getMemberDecl());
+ if (!Field || !isMemcpyableField(Field))
+ return 0;
+ MemberExpr *Arg0 = dyn_cast<MemberExpr>(MCE->getArg(0));
+ if (!Arg0 || Field != dyn_cast<FieldDecl>(Arg0->getMemberDecl()))
+ return 0;
+ return Field;
+ } else if (CallExpr *CE = dyn_cast<CallExpr>(S)) {
+ FunctionDecl *FD = dyn_cast<FunctionDecl>(CE->getCalleeDecl());
+ if (!FD || FD->getBuiltinID() != Builtin::BI__builtin_memcpy)
+ return 0;
+ Expr *DstPtr = CE->getArg(0);
+ if (ImplicitCastExpr *DC = dyn_cast<ImplicitCastExpr>(DstPtr))
+ DstPtr = DC->getSubExpr();
+ UnaryOperator *DUO = dyn_cast<UnaryOperator>(DstPtr);
+ if (!DUO || DUO->getOpcode() != UO_AddrOf)
+ return 0;
+ MemberExpr *ME = dyn_cast<MemberExpr>(DUO->getSubExpr());
+ if (!ME)
+ return 0;
+ FieldDecl *Field = dyn_cast<FieldDecl>(ME->getMemberDecl());
+ if (!Field || !isMemcpyableField(Field))
+ return 0;
+ Expr *SrcPtr = CE->getArg(1);
+ if (ImplicitCastExpr *SC = dyn_cast<ImplicitCastExpr>(SrcPtr))
+ SrcPtr = SC->getSubExpr();
+ UnaryOperator *SUO = dyn_cast<UnaryOperator>(SrcPtr);
+ if (!SUO || SUO->getOpcode() != UO_AddrOf)
+ return 0;
+ MemberExpr *ME2 = dyn_cast<MemberExpr>(SUO->getSubExpr());
+ if (!ME2 || Field != dyn_cast<FieldDecl>(ME2->getMemberDecl()))
+ return 0;
+ return Field;
+ }
+
+ return 0;
+ }
+
+ bool AssignmentsMemcpyable;
+ SmallVector<Stmt*, 16> AggregatedStmts;
+
+ public:
+
+ AssignmentMemcpyizer(CodeGenFunction &CGF, const CXXMethodDecl *AD,
+ FunctionArgList &Args)
+ : FieldMemcpyizer(CGF, AD->getParent(), Args[Args.size() - 1]),
+ AssignmentsMemcpyable(CGF.getLangOpts().getGC() == LangOptions::NonGC) {
+ assert(Args.size() == 2);
+ }
+
+ void emitAssignment(Stmt *S) {
+ FieldDecl *F = getMemcpyableField(S);
+ if (F) {
+ addMemcpyableField(F);
+ AggregatedStmts.push_back(S);
+ } else {
+ emitAggregatedStmts();
+ CGF.EmitStmt(S);
+ }
+ }
+
+ void emitAggregatedStmts() {
+ if (AggregatedStmts.size() <= 1) {
+ for (unsigned i = 0; i < AggregatedStmts.size(); ++i)
+ CGF.EmitStmt(AggregatedStmts[i]);
+ reset();
+ }
+
+ emitMemcpy();
+ AggregatedStmts.clear();
+ }
+
+ void finish() {
+ emitAggregatedStmts();
+ }
+ };
+
+}
+
/// EmitCtorPrologue - This routine generates necessary code to initialize
/// base classes and non-static data members belonging to this constructor.
void CodeGenFunction::EmitCtorPrologue(const CXXConstructorDecl *CD,
InitializeVTablePointers(ClassDecl);
+ ConstructorMemcpyizer CM(*this, CD, Args);
for (unsigned I = 0, E = MemberInitializers.size(); I != E; ++I)
- EmitMemberInitializer(*this, ClassDecl, MemberInitializers[I], CD, Args);
+ CM.addMemberInitializer(MemberInitializers[I]);
+ CM.finish();
}
static bool
ExitCXXTryStmt(*cast<CXXTryStmt>(Body), true);
}
+void CodeGenFunction::emitImplicitAssignmentOperatorBody(FunctionArgList &Args) {
+ const CXXMethodDecl *AssignOp = cast<CXXMethodDecl>(CurGD.getDecl());
+ const Stmt *RootS = AssignOp->getBody();
+ assert(isa<CompoundStmt>(RootS) &&
+ "Body of an implicit assignment operator should be compound stmt.");
+ const CompoundStmt *RootCS = cast<CompoundStmt>(RootS);
+
+ LexicalScope Scope(*this, RootCS->getSourceRange());
+
+ AssignmentMemcpyizer AM(*this, AssignOp, Args);
+ for (CompoundStmt::const_body_iterator I = RootCS->body_begin(),
+ E = RootCS->body_end();
+ I != E; ++I) {
+ AM.emitAssignment(*I);
+ }
+ AM.finish();
+}
+
namespace {
/// Call the operator delete associated with the current destructor.
struct CallDtorDelete : EHScopeStack::Cleanup {
projects / platform / upstream / llvm.git / commitdiff