Check in LLVM r95781.
diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp
new file mode 100644
index 0000000..382bfe5
--- /dev/null
+++ b/lib/AST/ExprConstant.cpp
@@ -0,0 +1,2039 @@
+//===--- ExprConstant.cpp - Expression Constant Evaluator -----------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the Expr constant evaluator.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/APValue.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/CharUnits.h"
+#include "clang/AST/RecordLayout.h"
+#include "clang/AST/StmtVisitor.h"
+#include "clang/AST/ASTDiagnostic.h"
+#include "clang/Basic/Builtins.h"
+#include "clang/Basic/TargetInfo.h"
+#include "llvm/ADT/SmallString.h"
+#include <cstring>
+
+using namespace clang;
+using llvm::APSInt;
+using llvm::APFloat;
+
+/// EvalInfo - This is a private struct used by the evaluator to capture
+/// information about a subexpression as it is folded. It retains information
+/// about the AST context, but also maintains information about the folded
+/// expression.
+///
+/// If an expression could be evaluated, it is still possible it is not a C
+/// "integer constant expression" or constant expression. If not, this struct
+/// captures information about how and why not.
+///
+/// One bit of information passed *into* the request for constant folding
+/// indicates whether the subexpression is "evaluated" or not according to C
+/// rules. For example, the RHS of (0 && foo()) is not evaluated. We can
+/// evaluate the expression regardless of what the RHS is, but C only allows
+/// certain things in certain situations.
+struct EvalInfo {
+ ASTContext &Ctx;
+
+ /// EvalResult - Contains information about the evaluation.
+ Expr::EvalResult &EvalResult;
+
+ /// AnyLValue - Stack based LValue results are not discarded.
+ bool AnyLValue;
+
+ EvalInfo(ASTContext &ctx, Expr::EvalResult& evalresult,
+ bool anylvalue = false)
+ : Ctx(ctx), EvalResult(evalresult), AnyLValue(anylvalue) {}
+};
+
+
+static bool EvaluateLValue(const Expr *E, APValue &Result, EvalInfo &Info);
+static bool EvaluatePointer(const Expr *E, APValue &Result, EvalInfo &Info);
+static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info);
+static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result,
+ EvalInfo &Info);
+static bool EvaluateFloat(const Expr *E, APFloat &Result, EvalInfo &Info);
+static bool EvaluateComplex(const Expr *E, APValue &Result, EvalInfo &Info);
+
+//===----------------------------------------------------------------------===//
+// Misc utilities
+//===----------------------------------------------------------------------===//
+
+static bool EvalPointerValueAsBool(APValue& Value, bool& Result) {
+ // FIXME: Is this accurate for all kinds of bases? If not, what would
+ // the check look like?
+ Result = Value.getLValueBase() || !Value.getLValueOffset().isZero();
+ return true;
+}
+
+static bool HandleConversionToBool(const Expr* E, bool& Result,
+ EvalInfo &Info) {
+ if (E->getType()->isIntegralType()) {
+ APSInt IntResult;
+ if (!EvaluateInteger(E, IntResult, Info))
+ return false;
+ Result = IntResult != 0;
+ return true;
+ } else if (E->getType()->isRealFloatingType()) {
+ APFloat FloatResult(0.0);
+ if (!EvaluateFloat(E, FloatResult, Info))
+ return false;
+ Result = !FloatResult.isZero();
+ return true;
+ } else if (E->getType()->hasPointerRepresentation()) {
+ APValue PointerResult;
+ if (!EvaluatePointer(E, PointerResult, Info))
+ return false;
+ return EvalPointerValueAsBool(PointerResult, Result);
+ } else if (E->getType()->isAnyComplexType()) {
+ APValue ComplexResult;
+ if (!EvaluateComplex(E, ComplexResult, Info))
+ return false;
+ if (ComplexResult.isComplexFloat()) {
+ Result = !ComplexResult.getComplexFloatReal().isZero() ||
+ !ComplexResult.getComplexFloatImag().isZero();
+ } else {
+ Result = ComplexResult.getComplexIntReal().getBoolValue() ||
+ ComplexResult.getComplexIntImag().getBoolValue();
+ }
+ return true;
+ }
+
+ return false;
+}
+
+static APSInt HandleFloatToIntCast(QualType DestType, QualType SrcType,
+ APFloat &Value, ASTContext &Ctx) {
+ unsigned DestWidth = Ctx.getIntWidth(DestType);
+ // Determine whether we are converting to unsigned or signed.
+ bool DestSigned = DestType->isSignedIntegerType();
+
+ // FIXME: Warning for overflow.
+ uint64_t Space[4];
+ bool ignored;
+ (void)Value.convertToInteger(Space, DestWidth, DestSigned,
+ llvm::APFloat::rmTowardZero, &ignored);
+ return APSInt(llvm::APInt(DestWidth, 4, Space), !DestSigned);
+}
+
+static APFloat HandleFloatToFloatCast(QualType DestType, QualType SrcType,
+ APFloat &Value, ASTContext &Ctx) {
+ bool ignored;
+ APFloat Result = Value;
+ Result.convert(Ctx.getFloatTypeSemantics(DestType),
+ APFloat::rmNearestTiesToEven, &ignored);
+ return Result;
+}
+
+static APSInt HandleIntToIntCast(QualType DestType, QualType SrcType,
+ APSInt &Value, ASTContext &Ctx) {
+ unsigned DestWidth = Ctx.getIntWidth(DestType);
+ APSInt Result = Value;
+ // Figure out if this is a truncate, extend or noop cast.
+ // If the input is signed, do a sign extend, noop, or truncate.
+ Result.extOrTrunc(DestWidth);
+ Result.setIsUnsigned(DestType->isUnsignedIntegerType());
+ return Result;
+}
+
+static APFloat HandleIntToFloatCast(QualType DestType, QualType SrcType,
+ APSInt &Value, ASTContext &Ctx) {
+
+ APFloat Result(Ctx.getFloatTypeSemantics(DestType), 1);
+ Result.convertFromAPInt(Value, Value.isSigned(),
+ APFloat::rmNearestTiesToEven);
+ return Result;
+}
+
+namespace {
+class HasSideEffect
+ : public StmtVisitor<HasSideEffect, bool> {
+ EvalInfo &Info;
+public:
+
+ HasSideEffect(EvalInfo &info) : Info(info) {}
+
+ // Unhandled nodes conservatively default to having side effects.
+ bool VisitStmt(Stmt *S) {
+ return true;
+ }
+
+ bool VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); }
+ bool VisitDeclRefExpr(DeclRefExpr *E) {
+ if (Info.Ctx.getCanonicalType(E->getType()).isVolatileQualified())
+ return true;
+ return false;
+ }
+ // We don't want to evaluate BlockExprs multiple times, as they generate
+ // a ton of code.
+ bool VisitBlockExpr(BlockExpr *E) { return true; }
+ bool VisitPredefinedExpr(PredefinedExpr *E) { return false; }
+ bool VisitCompoundLiteralExpr(CompoundLiteralExpr *E)
+ { return Visit(E->getInitializer()); }
+ bool VisitMemberExpr(MemberExpr *E) { return Visit(E->getBase()); }
+ bool VisitIntegerLiteral(IntegerLiteral *E) { return false; }
+ bool VisitFloatingLiteral(FloatingLiteral *E) { return false; }
+ bool VisitStringLiteral(StringLiteral *E) { return false; }
+ bool VisitCharacterLiteral(CharacterLiteral *E) { return false; }
+ bool VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E) { return false; }
+ bool VisitArraySubscriptExpr(ArraySubscriptExpr *E)
+ { return Visit(E->getLHS()) || Visit(E->getRHS()); }
+ bool VisitChooseExpr(ChooseExpr *E)
+ { return Visit(E->getChosenSubExpr(Info.Ctx)); }
+ bool VisitCastExpr(CastExpr *E) { return Visit(E->getSubExpr()); }
+ bool VisitBinAssign(BinaryOperator *E) { return true; }
+ bool VisitCompoundAssignOperator(BinaryOperator *E) { return true; }
+ bool VisitBinaryOperator(BinaryOperator *E)
+ { return Visit(E->getLHS()) || Visit(E->getRHS()); }
+ bool VisitUnaryPreInc(UnaryOperator *E) { return true; }
+ bool VisitUnaryPostInc(UnaryOperator *E) { return true; }
+ bool VisitUnaryPreDec(UnaryOperator *E) { return true; }
+ bool VisitUnaryPostDec(UnaryOperator *E) { return true; }
+ bool VisitUnaryDeref(UnaryOperator *E) {
+ if (Info.Ctx.getCanonicalType(E->getType()).isVolatileQualified())
+ return true;
+ return Visit(E->getSubExpr());
+ }
+ bool VisitUnaryOperator(UnaryOperator *E) { return Visit(E->getSubExpr()); }
+};
+
+} // end anonymous namespace
+
+//===----------------------------------------------------------------------===//
+// LValue Evaluation
+//===----------------------------------------------------------------------===//
+namespace {
+class LValueExprEvaluator
+ : public StmtVisitor<LValueExprEvaluator, APValue> {
+ EvalInfo &Info;
+public:
+
+ LValueExprEvaluator(EvalInfo &info) : Info(info) {}
+
+ APValue VisitStmt(Stmt *S) {
+ return APValue();
+ }
+
+ APValue VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); }
+ APValue VisitDeclRefExpr(DeclRefExpr *E);
+ APValue VisitPredefinedExpr(PredefinedExpr *E) { return APValue(E); }
+ APValue VisitCompoundLiteralExpr(CompoundLiteralExpr *E);
+ APValue VisitMemberExpr(MemberExpr *E);
+ APValue VisitStringLiteral(StringLiteral *E) { return APValue(E); }
+ APValue VisitObjCEncodeExpr(ObjCEncodeExpr *E) { return APValue(E); }
+ APValue VisitArraySubscriptExpr(ArraySubscriptExpr *E);
+ APValue VisitUnaryDeref(UnaryOperator *E);
+ APValue VisitUnaryExtension(const UnaryOperator *E)
+ { return Visit(E->getSubExpr()); }
+ APValue VisitChooseExpr(const ChooseExpr *E)
+ { return Visit(E->getChosenSubExpr(Info.Ctx)); }
+
+ APValue VisitCastExpr(CastExpr *E) {
+ switch (E->getCastKind()) {
+ default:
+ return APValue();
+
+ case CastExpr::CK_NoOp:
+ return Visit(E->getSubExpr());
+ }
+ }
+ // FIXME: Missing: __real__, __imag__
+};
+} // end anonymous namespace
+
+static bool EvaluateLValue(const Expr* E, APValue& Result, EvalInfo &Info) {
+ Result = LValueExprEvaluator(Info).Visit(const_cast<Expr*>(E));
+ return Result.isLValue();
+}
+
+APValue LValueExprEvaluator::VisitDeclRefExpr(DeclRefExpr *E) {
+ if (isa<FunctionDecl>(E->getDecl())) {
+ return APValue(E);
+ } else if (VarDecl* VD = dyn_cast<VarDecl>(E->getDecl())) {
+ if (!Info.AnyLValue && !VD->hasGlobalStorage())
+ return APValue();
+ if (!VD->getType()->isReferenceType())
+ return APValue(E);
+ // FIXME: Check whether VD might be overridden!
+ if (const Expr *Init = VD->getAnyInitializer())
+ return Visit(const_cast<Expr *>(Init));
+ }
+
+ return APValue();
+}
+
+APValue LValueExprEvaluator::VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
+ if (!Info.AnyLValue && !E->isFileScope())
+ return APValue();
+ return APValue(E);
+}
+
+APValue LValueExprEvaluator::VisitMemberExpr(MemberExpr *E) {
+ APValue result;
+ QualType Ty;
+ if (E->isArrow()) {
+ if (!EvaluatePointer(E->getBase(), result, Info))
+ return APValue();
+ Ty = E->getBase()->getType()->getAs<PointerType>()->getPointeeType();
+ } else {
+ result = Visit(E->getBase());
+ if (result.isUninit())
+ return APValue();
+ Ty = E->getBase()->getType();
+ }
+
+ RecordDecl *RD = Ty->getAs<RecordType>()->getDecl();
+ const ASTRecordLayout &RL = Info.Ctx.getASTRecordLayout(RD);
+
+ FieldDecl *FD = dyn_cast<FieldDecl>(E->getMemberDecl());
+ if (!FD) // FIXME: deal with other kinds of member expressions
+ return APValue();
+
+ if (FD->getType()->isReferenceType())
+ return APValue();
+
+ // FIXME: This is linear time.
+ unsigned i = 0;
+ for (RecordDecl::field_iterator Field = RD->field_begin(),
+ FieldEnd = RD->field_end();
+ Field != FieldEnd; (void)++Field, ++i) {
+ if (*Field == FD)
+ break;
+ }
+
+ result.setLValue(result.getLValueBase(),
+ result.getLValueOffset() +
+ CharUnits::fromQuantity(RL.getFieldOffset(i) / 8));
+
+ return result;
+}
+
+APValue LValueExprEvaluator::VisitArraySubscriptExpr(ArraySubscriptExpr *E) {
+ APValue Result;
+
+ if (!EvaluatePointer(E->getBase(), Result, Info))
+ return APValue();
+
+ APSInt Index;
+ if (!EvaluateInteger(E->getIdx(), Index, Info))
+ return APValue();
+
+ CharUnits ElementSize = Info.Ctx.getTypeSizeInChars(E->getType());
+
+ CharUnits Offset = Index.getSExtValue() * ElementSize;
+ Result.setLValue(Result.getLValueBase(),
+ Result.getLValueOffset() + Offset);
+ return Result;
+}
+
+APValue LValueExprEvaluator::VisitUnaryDeref(UnaryOperator *E) {
+ APValue Result;
+ if (!EvaluatePointer(E->getSubExpr(), Result, Info))
+ return APValue();
+ return Result;
+}
+
+//===----------------------------------------------------------------------===//
+// Pointer Evaluation
+//===----------------------------------------------------------------------===//
+
+namespace {
+class PointerExprEvaluator
+ : public StmtVisitor<PointerExprEvaluator, APValue> {
+ EvalInfo &Info;
+public:
+
+ PointerExprEvaluator(EvalInfo &info) : Info(info) {}
+
+ APValue VisitStmt(Stmt *S) {
+ return APValue();
+ }
+
+ APValue VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); }
+
+ APValue VisitBinaryOperator(const BinaryOperator *E);
+ APValue VisitCastExpr(CastExpr* E);
+ APValue VisitUnaryExtension(const UnaryOperator *E)
+ { return Visit(E->getSubExpr()); }
+ APValue VisitUnaryAddrOf(const UnaryOperator *E);
+ APValue VisitObjCStringLiteral(ObjCStringLiteral *E)
+ { return APValue(E); }
+ APValue VisitAddrLabelExpr(AddrLabelExpr *E)
+ { return APValue(E); }
+ APValue VisitCallExpr(CallExpr *E);
+ APValue VisitBlockExpr(BlockExpr *E) {
+ if (!E->hasBlockDeclRefExprs())
+ return APValue(E);
+ return APValue();
+ }
+ APValue VisitImplicitValueInitExpr(ImplicitValueInitExpr *E)
+ { return APValue((Expr*)0); }
+ APValue VisitConditionalOperator(ConditionalOperator *E);
+ APValue VisitChooseExpr(ChooseExpr *E)
+ { return Visit(E->getChosenSubExpr(Info.Ctx)); }
+ APValue VisitCXXNullPtrLiteralExpr(CXXNullPtrLiteralExpr *E)
+ { return APValue((Expr*)0); }
+ // FIXME: Missing: @protocol, @selector
+};
+} // end anonymous namespace
+
+static bool EvaluatePointer(const Expr* E, APValue& Result, EvalInfo &Info) {
+ if (!E->getType()->hasPointerRepresentation())
+ return false;
+ Result = PointerExprEvaluator(Info).Visit(const_cast<Expr*>(E));
+ return Result.isLValue();
+}
+
+APValue PointerExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
+ if (E->getOpcode() != BinaryOperator::Add &&
+ E->getOpcode() != BinaryOperator::Sub)
+ return APValue();
+
+ const Expr *PExp = E->getLHS();
+ const Expr *IExp = E->getRHS();
+ if (IExp->getType()->isPointerType())
+ std::swap(PExp, IExp);
+
+ APValue ResultLValue;
+ if (!EvaluatePointer(PExp, ResultLValue, Info))
+ return APValue();
+
+ llvm::APSInt AdditionalOffset(32);
+ if (!EvaluateInteger(IExp, AdditionalOffset, Info))
+ return APValue();
+
+ QualType PointeeType = PExp->getType()->getAs<PointerType>()->getPointeeType();
+ CharUnits SizeOfPointee;
+
+ // Explicitly handle GNU void* and function pointer arithmetic extensions.
+ if (PointeeType->isVoidType() || PointeeType->isFunctionType())
+ SizeOfPointee = CharUnits::One();
+ else
+ SizeOfPointee = Info.Ctx.getTypeSizeInChars(PointeeType);
+
+ CharUnits Offset = ResultLValue.getLValueOffset();
+
+ if (E->getOpcode() == BinaryOperator::Add)
+ Offset += AdditionalOffset.getLimitedValue() * SizeOfPointee;
+ else
+ Offset -= AdditionalOffset.getLimitedValue() * SizeOfPointee;
+
+ return APValue(ResultLValue.getLValueBase(), Offset);
+}
+
+APValue PointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) {
+ APValue result;
+ if (EvaluateLValue(E->getSubExpr(), result, Info))
+ return result;
+ return APValue();
+}
+
+
+APValue PointerExprEvaluator::VisitCastExpr(CastExpr* E) {
+ Expr* SubExpr = E->getSubExpr();
+
+ switch (E->getCastKind()) {
+ default:
+ break;
+
+ case CastExpr::CK_Unknown: {
+ // FIXME: The handling for CK_Unknown is ugly/shouldn't be necessary!
+
+ // Check for pointer->pointer cast
+ if (SubExpr->getType()->isPointerType() ||
+ SubExpr->getType()->isObjCObjectPointerType() ||
+ SubExpr->getType()->isNullPtrType() ||
+ SubExpr->getType()->isBlockPointerType())
+ return Visit(SubExpr);
+
+ if (SubExpr->getType()->isIntegralType()) {
+ APValue Result;
+ if (!EvaluateIntegerOrLValue(SubExpr, Result, Info))
+ break;
+
+ if (Result.isInt()) {
+ Result.getInt().extOrTrunc((unsigned)Info.Ctx.getTypeSize(E->getType()));
+ return APValue(0,
+ CharUnits::fromQuantity(Result.getInt().getZExtValue()));
+ }
+
+ // Cast is of an lvalue, no need to change value.
+ return Result;
+ }
+ break;
+ }
+
+ case CastExpr::CK_NoOp:
+ case CastExpr::CK_BitCast:
+ case CastExpr::CK_AnyPointerToObjCPointerCast:
+ case CastExpr::CK_AnyPointerToBlockPointerCast:
+ return Visit(SubExpr);
+
+ case CastExpr::CK_IntegralToPointer: {
+ APValue Result;
+ if (!EvaluateIntegerOrLValue(SubExpr, Result, Info))
+ break;
+
+ if (Result.isInt()) {
+ Result.getInt().extOrTrunc((unsigned)Info.Ctx.getTypeSize(E->getType()));
+ return APValue(0,
+ CharUnits::fromQuantity(Result.getInt().getZExtValue()));
+ }
+
+ // Cast is of an lvalue, no need to change value.
+ return Result;
+ }
+ case CastExpr::CK_ArrayToPointerDecay:
+ case CastExpr::CK_FunctionToPointerDecay: {
+ APValue Result;
+ if (EvaluateLValue(SubExpr, Result, Info))
+ return Result;
+ break;
+ }
+ }
+
+ return APValue();
+}
+
+APValue PointerExprEvaluator::VisitCallExpr(CallExpr *E) {
+ if (E->isBuiltinCall(Info.Ctx) ==
+ Builtin::BI__builtin___CFStringMakeConstantString ||
+ E->isBuiltinCall(Info.Ctx) ==
+ Builtin::BI__builtin___NSStringMakeConstantString)
+ return APValue(E);
+ return APValue();
+}
+
+APValue PointerExprEvaluator::VisitConditionalOperator(ConditionalOperator *E) {
+ bool BoolResult;
+ if (!HandleConversionToBool(E->getCond(), BoolResult, Info))
+ return APValue();
+
+ Expr* EvalExpr = BoolResult ? E->getTrueExpr() : E->getFalseExpr();
+
+ APValue Result;
+ if (EvaluatePointer(EvalExpr, Result, Info))
+ return Result;
+ return APValue();
+}
+
+//===----------------------------------------------------------------------===//
+// Vector Evaluation
+//===----------------------------------------------------------------------===//
+
+namespace {
+ class VectorExprEvaluator
+ : public StmtVisitor<VectorExprEvaluator, APValue> {
+ EvalInfo &Info;
+ APValue GetZeroVector(QualType VecType);
+ public:
+
+ VectorExprEvaluator(EvalInfo &info) : Info(info) {}
+
+ APValue VisitStmt(Stmt *S) {
+ return APValue();
+ }
+
+ APValue VisitParenExpr(ParenExpr *E)
+ { return Visit(E->getSubExpr()); }
+ APValue VisitUnaryExtension(const UnaryOperator *E)
+ { return Visit(E->getSubExpr()); }
+ APValue VisitUnaryPlus(const UnaryOperator *E)
+ { return Visit(E->getSubExpr()); }
+ APValue VisitUnaryReal(const UnaryOperator *E)
+ { return Visit(E->getSubExpr()); }
+ APValue VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E)
+ { return GetZeroVector(E->getType()); }
+ APValue VisitCastExpr(const CastExpr* E);
+ APValue VisitCompoundLiteralExpr(const CompoundLiteralExpr *E);
+ APValue VisitInitListExpr(const InitListExpr *E);
+ APValue VisitConditionalOperator(const ConditionalOperator *E);
+ APValue VisitChooseExpr(const ChooseExpr *E)
+ { return Visit(E->getChosenSubExpr(Info.Ctx)); }
+ APValue VisitUnaryImag(const UnaryOperator *E);
+ // FIXME: Missing: unary -, unary ~, binary add/sub/mul/div,
+ // binary comparisons, binary and/or/xor,
+ // shufflevector, ExtVectorElementExpr
+ // (Note that these require implementing conversions
+ // between vector types.)
+ };
+} // end anonymous namespace
+
+static bool EvaluateVector(const Expr* E, APValue& Result, EvalInfo &Info) {
+ if (!E->getType()->isVectorType())
+ return false;
+ Result = VectorExprEvaluator(Info).Visit(const_cast<Expr*>(E));
+ return !Result.isUninit();
+}
+
+APValue VectorExprEvaluator::VisitCastExpr(const CastExpr* E) {
+ const VectorType *VTy = E->getType()->getAs<VectorType>();
+ QualType EltTy = VTy->getElementType();
+ unsigned NElts = VTy->getNumElements();
+ unsigned EltWidth = Info.Ctx.getTypeSize(EltTy);
+
+ const Expr* SE = E->getSubExpr();
+ QualType SETy = SE->getType();
+ APValue Result = APValue();
+
+ // Check for vector->vector bitcast and scalar->vector splat.
+ if (SETy->isVectorType()) {
+ return this->Visit(const_cast<Expr*>(SE));
+ } else if (SETy->isIntegerType()) {
+ APSInt IntResult;
+ if (!EvaluateInteger(SE, IntResult, Info))
+ return APValue();
+ Result = APValue(IntResult);
+ } else if (SETy->isRealFloatingType()) {
+ APFloat F(0.0);
+ if (!EvaluateFloat(SE, F, Info))
+ return APValue();
+ Result = APValue(F);
+ } else
+ return APValue();
+
+ // For casts of a scalar to ExtVector, convert the scalar to the element type
+ // and splat it to all elements.
+ if (E->getType()->isExtVectorType()) {
+ if (EltTy->isIntegerType() && Result.isInt())
+ Result = APValue(HandleIntToIntCast(EltTy, SETy, Result.getInt(),
+ Info.Ctx));
+ else if (EltTy->isIntegerType())
+ Result = APValue(HandleFloatToIntCast(EltTy, SETy, Result.getFloat(),
+ Info.Ctx));
+ else if (EltTy->isRealFloatingType() && Result.isInt())
+ Result = APValue(HandleIntToFloatCast(EltTy, SETy, Result.getInt(),
+ Info.Ctx));
+ else if (EltTy->isRealFloatingType())
+ Result = APValue(HandleFloatToFloatCast(EltTy, SETy, Result.getFloat(),
+ Info.Ctx));
+ else
+ return APValue();
+
+ // Splat and create vector APValue.
+ llvm::SmallVector<APValue, 4> Elts(NElts, Result);
+ return APValue(&Elts[0], Elts.size());
+ }
+
+ // For casts of a scalar to regular gcc-style vector type, bitcast the scalar
+ // to the vector. To construct the APValue vector initializer, bitcast the
+ // initializing value to an APInt, and shift out the bits pertaining to each
+ // element.
+ APSInt Init;
+ Init = Result.isInt() ? Result.getInt() : Result.getFloat().bitcastToAPInt();
+
+ llvm::SmallVector<APValue, 4> Elts;
+ for (unsigned i = 0; i != NElts; ++i) {
+ APSInt Tmp = Init;
+ Tmp.extOrTrunc(EltWidth);
+
+ if (EltTy->isIntegerType())
+ Elts.push_back(APValue(Tmp));
+ else if (EltTy->isRealFloatingType())
+ Elts.push_back(APValue(APFloat(Tmp)));
+ else
+ return APValue();
+
+ Init >>= EltWidth;
+ }
+ return APValue(&Elts[0], Elts.size());
+}
+
+APValue
+VectorExprEvaluator::VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) {
+ return this->Visit(const_cast<Expr*>(E->getInitializer()));
+}
+
+APValue
+VectorExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
+ const VectorType *VT = E->getType()->getAs<VectorType>();
+ unsigned NumInits = E->getNumInits();
+ unsigned NumElements = VT->getNumElements();
+
+ QualType EltTy = VT->getElementType();
+ llvm::SmallVector<APValue, 4> Elements;
+
+ for (unsigned i = 0; i < NumElements; i++) {
+ if (EltTy->isIntegerType()) {
+ llvm::APSInt sInt(32);
+ if (i < NumInits) {
+ if (!EvaluateInteger(E->getInit(i), sInt, Info))
+ return APValue();
+ } else {
+ sInt = Info.Ctx.MakeIntValue(0, EltTy);
+ }
+ Elements.push_back(APValue(sInt));
+ } else {
+ llvm::APFloat f(0.0);
+ if (i < NumInits) {
+ if (!EvaluateFloat(E->getInit(i), f, Info))
+ return APValue();
+ } else {
+ f = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(EltTy));
+ }
+ Elements.push_back(APValue(f));
+ }
+ }
+ return APValue(&Elements[0], Elements.size());
+}
+
+APValue
+VectorExprEvaluator::GetZeroVector(QualType T) {
+ const VectorType *VT = T->getAs<VectorType>();
+ QualType EltTy = VT->getElementType();
+ APValue ZeroElement;
+ if (EltTy->isIntegerType())
+ ZeroElement = APValue(Info.Ctx.MakeIntValue(0, EltTy));
+ else
+ ZeroElement =
+ APValue(APFloat::getZero(Info.Ctx.getFloatTypeSemantics(EltTy)));
+
+ llvm::SmallVector<APValue, 4> Elements(VT->getNumElements(), ZeroElement);
+ return APValue(&Elements[0], Elements.size());
+}
+
+APValue VectorExprEvaluator::VisitConditionalOperator(const ConditionalOperator *E) {
+ bool BoolResult;
+ if (!HandleConversionToBool(E->getCond(), BoolResult, Info))
+ return APValue();
+
+ Expr* EvalExpr = BoolResult ? E->getTrueExpr() : E->getFalseExpr();
+
+ APValue Result;
+ if (EvaluateVector(EvalExpr, Result, Info))
+ return Result;
+ return APValue();
+}
+
+APValue VectorExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
+ if (!E->getSubExpr()->isEvaluatable(Info.Ctx))
+ Info.EvalResult.HasSideEffects = true;
+ return GetZeroVector(E->getType());
+}
+
+//===----------------------------------------------------------------------===//
+// Integer Evaluation
+//===----------------------------------------------------------------------===//
+
+namespace {
+class IntExprEvaluator
+ : public StmtVisitor<IntExprEvaluator, bool> {
+ EvalInfo &Info;
+ APValue &Result;
+public:
+ IntExprEvaluator(EvalInfo &info, APValue &result)
+ : Info(info), Result(result) {}
+
+ bool Success(const llvm::APSInt &SI, const Expr *E) {
+ assert(E->getType()->isIntegralType() && "Invalid evaluation result.");
+ assert(SI.isSigned() == E->getType()->isSignedIntegerType() &&
+ "Invalid evaluation result.");
+ assert(SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&
+ "Invalid evaluation result.");
+ Result = APValue(SI);
+ return true;
+ }
+
+ bool Success(const llvm::APInt &I, const Expr *E) {
+ assert(E->getType()->isIntegralType() && "Invalid evaluation result.");
+ assert(I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&
+ "Invalid evaluation result.");
+ Result = APValue(APSInt(I));
+ Result.getInt().setIsUnsigned(E->getType()->isUnsignedIntegerType());
+ return true;
+ }
+
+ bool Success(uint64_t Value, const Expr *E) {
+ assert(E->getType()->isIntegralType() && "Invalid evaluation result.");
+ Result = APValue(Info.Ctx.MakeIntValue(Value, E->getType()));
+ return true;
+ }
+
+ bool Error(SourceLocation L, diag::kind D, const Expr *E) {
+ // Take the first error.
+ if (Info.EvalResult.Diag == 0) {
+ Info.EvalResult.DiagLoc = L;
+ Info.EvalResult.Diag = D;
+ Info.EvalResult.DiagExpr = E;
+ }
+ return false;
+ }
+
+ //===--------------------------------------------------------------------===//
+ // Visitor Methods
+ //===--------------------------------------------------------------------===//
+
+ bool VisitStmt(Stmt *) {
+ assert(0 && "This should be called on integers, stmts are not integers");
+ return false;
+ }
+
+ bool VisitExpr(Expr *E) {
+ return Error(E->getLocStart(), diag::note_invalid_subexpr_in_ice, E);
+ }
+
+ bool VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); }
+
+ bool VisitIntegerLiteral(const IntegerLiteral *E) {
+ return Success(E->getValue(), E);
+ }
+ bool VisitCharacterLiteral(const CharacterLiteral *E) {
+ return Success(E->getValue(), E);
+ }
+ bool VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) {
+ // Per gcc docs "this built-in function ignores top level
+ // qualifiers". We need to use the canonical version to properly
+ // be able to strip CRV qualifiers from the type.
+ QualType T0 = Info.Ctx.getCanonicalType(E->getArgType1());
+ QualType T1 = Info.Ctx.getCanonicalType(E->getArgType2());
+ return Success(Info.Ctx.typesAreCompatible(T0.getUnqualifiedType(),
+ T1.getUnqualifiedType()),
+ E);
+ }
+
+ bool CheckReferencedDecl(const Expr *E, const Decl *D);
+ bool VisitDeclRefExpr(const DeclRefExpr *E) {
+ return CheckReferencedDecl(E, E->getDecl());
+ }
+ bool VisitMemberExpr(const MemberExpr *E) {
+ if (CheckReferencedDecl(E, E->getMemberDecl())) {
+ // Conservatively assume a MemberExpr will have side-effects
+ Info.EvalResult.HasSideEffects = true;
+ return true;
+ }
+ return false;
+ }
+
+ bool VisitCallExpr(const CallExpr *E);
+ bool VisitBinaryOperator(const BinaryOperator *E);
+ bool VisitUnaryOperator(const UnaryOperator *E);
+ bool VisitConditionalOperator(const ConditionalOperator *E);
+
+ bool VisitCastExpr(CastExpr* E);
+ bool VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E);
+
+ bool VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) {
+ return Success(E->getValue(), E);
+ }
+
+ bool VisitGNUNullExpr(const GNUNullExpr *E) {
+ return Success(0, E);
+ }
+
+ bool VisitCXXZeroInitValueExpr(const CXXZeroInitValueExpr *E) {
+ return Success(0, E);
+ }
+
+ bool VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) {
+ return Success(0, E);
+ }
+
+ bool VisitUnaryTypeTraitExpr(const UnaryTypeTraitExpr *E) {
+ return Success(E->EvaluateTrait(Info.Ctx), E);
+ }
+
+ bool VisitChooseExpr(const ChooseExpr *E) {
+ return Visit(E->getChosenSubExpr(Info.Ctx));
+ }
+
+ bool VisitUnaryReal(const UnaryOperator *E);
+ bool VisitUnaryImag(const UnaryOperator *E);
+
+private:
+ CharUnits GetAlignOfExpr(const Expr *E);
+ CharUnits GetAlignOfType(QualType T);
+ // FIXME: Missing: array subscript of vector, member of vector
+};
+} // end anonymous namespace
+
+static bool EvaluateIntegerOrLValue(const Expr* E, APValue &Result, EvalInfo &Info) {
+ if (!E->getType()->isIntegralType())
+ return false;
+
+ return IntExprEvaluator(Info, Result).Visit(const_cast<Expr*>(E));
+}
+
+static bool EvaluateInteger(const Expr* E, APSInt &Result, EvalInfo &Info) {
+ APValue Val;
+ if (!EvaluateIntegerOrLValue(E, Val, Info) || !Val.isInt())
+ return false;
+ Result = Val.getInt();
+ return true;
+}
+
+bool IntExprEvaluator::CheckReferencedDecl(const Expr* E, const Decl* D) {
+ // Enums are integer constant exprs.
+ if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(D))
+ return Success(ECD->getInitVal(), E);
+
+ // In C++, const, non-volatile integers initialized with ICEs are ICEs.
+ // In C, they can also be folded, although they are not ICEs.
+ if (Info.Ctx.getCanonicalType(E->getType()).getCVRQualifiers()
+ == Qualifiers::Const) {
+
+ if (isa<ParmVarDecl>(D))
+ return Error(E->getLocStart(), diag::note_invalid_subexpr_in_ice, E);
+
+ if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
+ if (const Expr *Init = VD->getAnyInitializer()) {
+ if (APValue *V = VD->getEvaluatedValue()) {
+ if (V->isInt())
+ return Success(V->getInt(), E);
+ return Error(E->getLocStart(), diag::note_invalid_subexpr_in_ice, E);
+ }
+
+ if (VD->isEvaluatingValue())
+ return Error(E->getLocStart(), diag::note_invalid_subexpr_in_ice, E);
+
+ VD->setEvaluatingValue();
+
+ if (Visit(const_cast<Expr*>(Init))) {
+ // Cache the evaluated value in the variable declaration.
+ VD->setEvaluatedValue(Result);
+ return true;
+ }
+
+ VD->setEvaluatedValue(APValue());
+ return false;
+ }
+ }
+ }
+
+ // Otherwise, random variable references are not constants.
+ return Error(E->getLocStart(), diag::note_invalid_subexpr_in_ice, E);
+}
+
+/// EvaluateBuiltinClassifyType - Evaluate __builtin_classify_type the same way
+/// as GCC.
+static int EvaluateBuiltinClassifyType(const CallExpr *E) {
+ // The following enum mimics the values returned by GCC.
+ // FIXME: Does GCC differ between lvalue and rvalue references here?
+ enum gcc_type_class {
+ no_type_class = -1,
+ void_type_class, integer_type_class, char_type_class,
+ enumeral_type_class, boolean_type_class,
+ pointer_type_class, reference_type_class, offset_type_class,
+ real_type_class, complex_type_class,
+ function_type_class, method_type_class,
+ record_type_class, union_type_class,
+ array_type_class, string_type_class,
+ lang_type_class
+ };
+
+ // If no argument was supplied, default to "no_type_class". This isn't
+ // ideal, however it is what gcc does.
+ if (E->getNumArgs() == 0)
+ return no_type_class;
+
+ QualType ArgTy = E->getArg(0)->getType();
+ if (ArgTy->isVoidType())
+ return void_type_class;
+ else if (ArgTy->isEnumeralType())
+ return enumeral_type_class;
+ else if (ArgTy->isBooleanType())
+ return boolean_type_class;
+ else if (ArgTy->isCharType())
+ return string_type_class; // gcc doesn't appear to use char_type_class
+ else if (ArgTy->isIntegerType())
+ return integer_type_class;
+ else if (ArgTy->isPointerType())
+ return pointer_type_class;
+ else if (ArgTy->isReferenceType())
+ return reference_type_class;
+ else if (ArgTy->isRealType())
+ return real_type_class;
+ else if (ArgTy->isComplexType())
+ return complex_type_class;
+ else if (ArgTy->isFunctionType())
+ return function_type_class;
+ else if (ArgTy->isStructureType())
+ return record_type_class;
+ else if (ArgTy->isUnionType())
+ return union_type_class;
+ else if (ArgTy->isArrayType())
+ return array_type_class;
+ else if (ArgTy->isUnionType())
+ return union_type_class;
+ else // FIXME: offset_type_class, method_type_class, & lang_type_class?
+ assert(0 && "CallExpr::isBuiltinClassifyType(): unimplemented type");
+ return -1;
+}
+
+bool IntExprEvaluator::VisitCallExpr(const CallExpr *E) {
+ switch (E->isBuiltinCall(Info.Ctx)) {
+ default:
+ return Error(E->getLocStart(), diag::note_invalid_subexpr_in_ice, E);
+
+ case Builtin::BI__builtin_object_size: {
+ const Expr *Arg = E->getArg(0)->IgnoreParens();
+ Expr::EvalResult Base;
+
+ // TODO: Perhaps we should let LLVM lower this?
+ if (Arg->EvaluateAsAny(Base, Info.Ctx)
+ && Base.Val.getKind() == APValue::LValue
+ && !Base.HasSideEffects)
+ if (const Expr *LVBase = Base.Val.getLValueBase())
+ if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(LVBase)) {
+ if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) {
+ if (!VD->getType()->isIncompleteType()
+ && VD->getType()->isObjectType()
+ && !VD->getType()->isVariablyModifiedType()
+ && !VD->getType()->isDependentType()) {
+ CharUnits Size = Info.Ctx.getTypeSizeInChars(VD->getType());
+ CharUnits Offset = Base.Val.getLValueOffset();
+ if (!Offset.isNegative() && Offset <= Size)
+ Size -= Offset;
+ else
+ Size = CharUnits::Zero();
+ return Success(Size.getQuantity(), E);
+ }
+ }
+ }
+
+ // If evaluating the argument has side-effects we can't determine
+ // the size of the object and lower it to unknown now.
+ if (E->getArg(0)->HasSideEffects(Info.Ctx)) {
+ if (E->getArg(1)->EvaluateAsInt(Info.Ctx).getZExtValue() <= 1)
+ return Success(-1ULL, E);
+ return Success(0, E);
+ }
+
+ return Error(E->getLocStart(), diag::note_invalid_subexpr_in_ice, E);
+ }
+
+ case Builtin::BI__builtin_classify_type:
+ return Success(EvaluateBuiltinClassifyType(E), E);
+
+ case Builtin::BI__builtin_constant_p:
+ // __builtin_constant_p always has one operand: it returns true if that
+ // operand can be folded, false otherwise.
+ return Success(E->getArg(0)->isEvaluatable(Info.Ctx), E);
+
+ case Builtin::BI__builtin_eh_return_data_regno: {
+ int Operand = E->getArg(0)->EvaluateAsInt(Info.Ctx).getZExtValue();
+ Operand = Info.Ctx.Target.getEHDataRegisterNumber(Operand);
+ return Success(Operand, E);
+ }
+ }
+}
+
+bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
+ if (E->getOpcode() == BinaryOperator::Comma) {
+ if (!Visit(E->getRHS()))
+ return false;
+
+ // If we can't evaluate the LHS, it might have side effects;
+ // conservatively mark it.
+ if (!E->getLHS()->isEvaluatable(Info.Ctx))
+ Info.EvalResult.HasSideEffects = true;
+
+ return true;
+ }
+
+ if (E->isLogicalOp()) {
+ // These need to be handled specially because the operands aren't
+ // necessarily integral
+ bool lhsResult, rhsResult;
+
+ if (HandleConversionToBool(E->getLHS(), lhsResult, Info)) {
+ // We were able to evaluate the LHS, see if we can get away with not
+ // evaluating the RHS: 0 && X -> 0, 1 || X -> 1
+ if (lhsResult == (E->getOpcode() == BinaryOperator::LOr))
+ return Success(lhsResult, E);
+
+ if (HandleConversionToBool(E->getRHS(), rhsResult, Info)) {
+ if (E->getOpcode() == BinaryOperator::LOr)
+ return Success(lhsResult || rhsResult, E);
+ else
+ return Success(lhsResult && rhsResult, E);
+ }
+ } else {
+ if (HandleConversionToBool(E->getRHS(), rhsResult, Info)) {
+ // We can't evaluate the LHS; however, sometimes the result
+ // is determined by the RHS: X && 0 -> 0, X || 1 -> 1.
+ if (rhsResult == (E->getOpcode() == BinaryOperator::LOr) ||
+ !rhsResult == (E->getOpcode() == BinaryOperator::LAnd)) {
+ // Since we weren't able to evaluate the left hand side, it
+ // must have had side effects.
+ Info.EvalResult.HasSideEffects = true;
+
+ return Success(rhsResult, E);
+ }
+ }
+ }
+
+ return false;
+ }
+
+ QualType LHSTy = E->getLHS()->getType();
+ QualType RHSTy = E->getRHS()->getType();
+
+ if (LHSTy->isAnyComplexType()) {
+ assert(RHSTy->isAnyComplexType() && "Invalid comparison");
+ APValue LHS, RHS;
+
+ if (!EvaluateComplex(E->getLHS(), LHS, Info))
+ return false;
+
+ if (!EvaluateComplex(E->getRHS(), RHS, Info))
+ return false;
+
+ if (LHS.isComplexFloat()) {
+ APFloat::cmpResult CR_r =
+ LHS.getComplexFloatReal().compare(RHS.getComplexFloatReal());
+ APFloat::cmpResult CR_i =
+ LHS.getComplexFloatImag().compare(RHS.getComplexFloatImag());
+
+ if (E->getOpcode() == BinaryOperator::EQ)
+ return Success((CR_r == APFloat::cmpEqual &&
+ CR_i == APFloat::cmpEqual), E);
+ else {
+ assert(E->getOpcode() == BinaryOperator::NE &&
+ "Invalid complex comparison.");
+ return Success(((CR_r == APFloat::cmpGreaterThan ||
+ CR_r == APFloat::cmpLessThan) &&
+ (CR_i == APFloat::cmpGreaterThan ||
+ CR_i == APFloat::cmpLessThan)), E);
+ }
+ } else {
+ if (E->getOpcode() == BinaryOperator::EQ)
+ return Success((LHS.getComplexIntReal() == RHS.getComplexIntReal() &&
+ LHS.getComplexIntImag() == RHS.getComplexIntImag()), E);
+ else {
+ assert(E->getOpcode() == BinaryOperator::NE &&
+ "Invalid compex comparison.");
+ return Success((LHS.getComplexIntReal() != RHS.getComplexIntReal() ||
+ LHS.getComplexIntImag() != RHS.getComplexIntImag()), E);
+ }
+ }
+ }
+
+ if (LHSTy->isRealFloatingType() &&
+ RHSTy->isRealFloatingType()) {
+ APFloat RHS(0.0), LHS(0.0);
+
+ if (!EvaluateFloat(E->getRHS(), RHS, Info))
+ return false;
+
+ if (!EvaluateFloat(E->getLHS(), LHS, Info))
+ return false;
+
+ APFloat::cmpResult CR = LHS.compare(RHS);
+
+ switch (E->getOpcode()) {
+ default:
+ assert(0 && "Invalid binary operator!");
+ case BinaryOperator::LT:
+ return Success(CR == APFloat::cmpLessThan, E);
+ case BinaryOperator::GT:
+ return Success(CR == APFloat::cmpGreaterThan, E);
+ case BinaryOperator::LE:
+ return Success(CR == APFloat::cmpLessThan || CR == APFloat::cmpEqual, E);
+ case BinaryOperator::GE:
+ return Success(CR == APFloat::cmpGreaterThan || CR == APFloat::cmpEqual,
+ E);
+ case BinaryOperator::EQ:
+ return Success(CR == APFloat::cmpEqual, E);
+ case BinaryOperator::NE:
+ return Success(CR == APFloat::cmpGreaterThan
+ || CR == APFloat::cmpLessThan, E);
+ }
+ }
+
+ if (LHSTy->isPointerType() && RHSTy->isPointerType()) {
+ if (E->getOpcode() == BinaryOperator::Sub || E->isEqualityOp()) {
+ APValue LHSValue;
+ if (!EvaluatePointer(E->getLHS(), LHSValue, Info))
+ return false;
+
+ APValue RHSValue;
+ if (!EvaluatePointer(E->getRHS(), RHSValue, Info))
+ return false;
+
+ // Reject any bases from the normal codepath; we special-case comparisons
+ // to null.
+ if (LHSValue.getLValueBase()) {
+ if (!E->isEqualityOp())
+ return false;
+ if (RHSValue.getLValueBase() || !RHSValue.getLValueOffset().isZero())
+ return false;
+ bool bres;
+ if (!EvalPointerValueAsBool(LHSValue, bres))
+ return false;
+ return Success(bres ^ (E->getOpcode() == BinaryOperator::EQ), E);
+ } else if (RHSValue.getLValueBase()) {
+ if (!E->isEqualityOp())
+ return false;
+ if (LHSValue.getLValueBase() || !LHSValue.getLValueOffset().isZero())
+ return false;
+ bool bres;
+ if (!EvalPointerValueAsBool(RHSValue, bres))
+ return false;
+ return Success(bres ^ (E->getOpcode() == BinaryOperator::EQ), E);
+ }
+
+ if (E->getOpcode() == BinaryOperator::Sub) {
+ const QualType Type = E->getLHS()->getType();
+ const QualType ElementType = Type->getAs<PointerType>()->getPointeeType();
+
+ CharUnits ElementSize = CharUnits::One();
+ if (!ElementType->isVoidType() && !ElementType->isFunctionType())
+ ElementSize = Info.Ctx.getTypeSizeInChars(ElementType);
+
+ CharUnits Diff = LHSValue.getLValueOffset() -
+ RHSValue.getLValueOffset();
+ return Success(Diff / ElementSize, E);
+ }
+ bool Result;
+ if (E->getOpcode() == BinaryOperator::EQ) {
+ Result = LHSValue.getLValueOffset() == RHSValue.getLValueOffset();
+ } else {
+ Result = LHSValue.getLValueOffset() != RHSValue.getLValueOffset();
+ }
+ return Success(Result, E);
+ }
+ }
+ if (!LHSTy->isIntegralType() ||
+ !RHSTy->isIntegralType()) {
+ // We can't continue from here for non-integral types, and they
+ // could potentially confuse the following operations.
+ return false;
+ }
+
+ // The LHS of a constant expr is always evaluated and needed.
+ if (!Visit(E->getLHS()))
+ return false; // error in subexpression.
+
+ APValue RHSVal;
+ if (!EvaluateIntegerOrLValue(E->getRHS(), RHSVal, Info))
+ return false;
+
+ // Handle cases like (unsigned long)&a + 4.
+ if (E->isAdditiveOp() && Result.isLValue() && RHSVal.isInt()) {
+ CharUnits Offset = Result.getLValueOffset();
+ CharUnits AdditionalOffset = CharUnits::fromQuantity(
+ RHSVal.getInt().getZExtValue());
+ if (E->getOpcode() == BinaryOperator::Add)
+ Offset += AdditionalOffset;
+ else
+ Offset -= AdditionalOffset;
+ Result = APValue(Result.getLValueBase(), Offset);
+ return true;
+ }
+
+ // Handle cases like 4 + (unsigned long)&a
+ if (E->getOpcode() == BinaryOperator::Add &&
+ RHSVal.isLValue() && Result.isInt()) {
+ CharUnits Offset = RHSVal.getLValueOffset();
+ Offset += CharUnits::fromQuantity(Result.getInt().getZExtValue());
+ Result = APValue(RHSVal.getLValueBase(), Offset);
+ return true;
+ }
+
+ // All the following cases expect both operands to be an integer
+ if (!Result.isInt() || !RHSVal.isInt())
+ return false;
+
+ APSInt& RHS = RHSVal.getInt();
+
+ switch (E->getOpcode()) {
+ default:
+ return Error(E->getOperatorLoc(), diag::note_invalid_subexpr_in_ice, E);
+ case BinaryOperator::Mul: return Success(Result.getInt() * RHS, E);
+ case BinaryOperator::Add: return Success(Result.getInt() + RHS, E);
+ case BinaryOperator::Sub: return Success(Result.getInt() - RHS, E);
+ case BinaryOperator::And: return Success(Result.getInt() & RHS, E);
+ case BinaryOperator::Xor: return Success(Result.getInt() ^ RHS, E);
+ case BinaryOperator::Or: return Success(Result.getInt() | RHS, E);
+ case BinaryOperator::Div:
+ if (RHS == 0)
+ return Error(E->getOperatorLoc(), diag::note_expr_divide_by_zero, E);
+ return Success(Result.getInt() / RHS, E);
+ case BinaryOperator::Rem:
+ if (RHS == 0)
+ return Error(E->getOperatorLoc(), diag::note_expr_divide_by_zero, E);
+ return Success(Result.getInt() % RHS, E);
+ case BinaryOperator::Shl: {
+ // FIXME: Warn about out of range shift amounts!
+ unsigned SA =
+ (unsigned) RHS.getLimitedValue(Result.getInt().getBitWidth()-1);
+ return Success(Result.getInt() << SA, E);
+ }
+ case BinaryOperator::Shr: {
+ unsigned SA =
+ (unsigned) RHS.getLimitedValue(Result.getInt().getBitWidth()-1);
+ return Success(Result.getInt() >> SA, E);
+ }
+
+ case BinaryOperator::LT: return Success(Result.getInt() < RHS, E);
+ case BinaryOperator::GT: return Success(Result.getInt() > RHS, E);
+ case BinaryOperator::LE: return Success(Result.getInt() <= RHS, E);
+ case BinaryOperator::GE: return Success(Result.getInt() >= RHS, E);
+ case BinaryOperator::EQ: return Success(Result.getInt() == RHS, E);
+ case BinaryOperator::NE: return Success(Result.getInt() != RHS, E);
+ }
+}
+
+bool IntExprEvaluator::VisitConditionalOperator(const ConditionalOperator *E) {
+ bool Cond;
+ if (!HandleConversionToBool(E->getCond(), Cond, Info))
+ return false;
+
+ return Visit(Cond ? E->getTrueExpr() : E->getFalseExpr());
+}
+
+CharUnits IntExprEvaluator::GetAlignOfType(QualType T) {
+ // C++ [expr.sizeof]p2: "When applied to a reference or a reference type,
+ // the result is the size of the referenced type."
+ // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the
+ // result shall be the alignment of the referenced type."
+ if (const ReferenceType *Ref = T->getAs<ReferenceType>())
+ T = Ref->getPointeeType();
+
+ // Get information about the alignment.
+ unsigned CharSize = Info.Ctx.Target.getCharWidth();
+
+ // __alignof is defined to return the preferred alignment.
+ return CharUnits::fromQuantity(
+ Info.Ctx.getPreferredTypeAlign(T.getTypePtr()) / CharSize);
+}
+
+CharUnits IntExprEvaluator::GetAlignOfExpr(const Expr *E) {
+ E = E->IgnoreParens();
+
+ // alignof decl is always accepted, even if it doesn't make sense: we default
+ // to 1 in those cases.
+ if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
+ return Info.Ctx.getDeclAlign(DRE->getDecl(),
+ /*RefAsPointee*/true);
+
+ if (const MemberExpr *ME = dyn_cast<MemberExpr>(E))
+ return Info.Ctx.getDeclAlign(ME->getMemberDecl(),
+ /*RefAsPointee*/true);
+
+ return GetAlignOfType(E->getType());
+}
+
+
+/// VisitSizeAlignOfExpr - Evaluate a sizeof or alignof with a result as the
+/// expression's type.
+bool IntExprEvaluator::VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E) {
+ // Handle alignof separately.
+ if (!E->isSizeOf()) {
+ if (E->isArgumentType())
+ return Success(GetAlignOfType(E->getArgumentType()).getQuantity(), E);
+ else
+ return Success(GetAlignOfExpr(E->getArgumentExpr()).getQuantity(), E);
+ }
+
+ QualType SrcTy = E->getTypeOfArgument();
+ // C++ [expr.sizeof]p2: "When applied to a reference or a reference type,
+ // the result is the size of the referenced type."
+ // C++ [expr.alignof]p3: "When alignof is applied to a reference type, the
+ // result shall be the alignment of the referenced type."
+ if (const ReferenceType *Ref = SrcTy->getAs<ReferenceType>())
+ SrcTy = Ref->getPointeeType();
+
+ // sizeof(void), __alignof__(void), sizeof(function) = 1 as a gcc
+ // extension.
+ if (SrcTy->isVoidType() || SrcTy->isFunctionType())
+ return Success(1, E);
+
+ // sizeof(vla) is not a constantexpr: C99 6.5.3.4p2.
+ if (!SrcTy->isConstantSizeType())
+ return false;
+
+ // Get information about the size.
+ return Success(Info.Ctx.getTypeSizeInChars(SrcTy).getQuantity(), E);
+}
+
+bool IntExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
+ // Special case unary operators that do not need their subexpression
+ // evaluated. offsetof/sizeof/alignof are all special.
+ if (E->isOffsetOfOp()) {
+ // The AST for offsetof is defined in such a way that we can just
+ // directly Evaluate it as an l-value.
+ APValue LV;
+ if (!EvaluateLValue(E->getSubExpr(), LV, Info))
+ return false;
+ if (LV.getLValueBase())
+ return false;
+ return Success(LV.getLValueOffset().getQuantity(), E);
+ }
+
+ if (E->getOpcode() == UnaryOperator::LNot) {
+ // LNot's operand isn't necessarily an integer, so we handle it specially.
+ bool bres;
+ if (!HandleConversionToBool(E->getSubExpr(), bres, Info))
+ return false;
+ return Success(!bres, E);
+ }
+
+ // Only handle integral operations...
+ if (!E->getSubExpr()->getType()->isIntegralType())
+ return false;
+
+ // Get the operand value into 'Result'.
+ if (!Visit(E->getSubExpr()))
+ return false;
+
+ switch (E->getOpcode()) {
+ default:
+ // Address, indirect, pre/post inc/dec, etc are not valid constant exprs.
+ // See C99 6.6p3.
+ return Error(E->getOperatorLoc(), diag::note_invalid_subexpr_in_ice, E);
+ case UnaryOperator::Extension:
+ // FIXME: Should extension allow i-c-e extension expressions in its scope?
+ // If so, we could clear the diagnostic ID.
+ return true;
+ case UnaryOperator::Plus:
+ // The result is always just the subexpr.
+ return true;
+ case UnaryOperator::Minus:
+ if (!Result.isInt()) return false;
+ return Success(-Result.getInt(), E);
+ case UnaryOperator::Not:
+ if (!Result.isInt()) return false;
+ return Success(~Result.getInt(), E);
+ }
+}
+
+/// HandleCast - This is used to evaluate implicit or explicit casts where the
+/// result type is integer.
+bool IntExprEvaluator::VisitCastExpr(CastExpr *E) {
+ Expr *SubExpr = E->getSubExpr();
+ QualType DestType = E->getType();
+ QualType SrcType = SubExpr->getType();
+
+ if (DestType->isBooleanType()) {
+ bool BoolResult;
+ if (!HandleConversionToBool(SubExpr, BoolResult, Info))
+ return false;
+ return Success(BoolResult, E);
+ }
+
+ // Handle simple integer->integer casts.
+ if (SrcType->isIntegralType()) {
+ if (!Visit(SubExpr))
+ return false;
+
+ if (!Result.isInt()) {
+ // Only allow casts of lvalues if they are lossless.
+ return Info.Ctx.getTypeSize(DestType) == Info.Ctx.getTypeSize(SrcType);
+ }
+
+ return Success(HandleIntToIntCast(DestType, SrcType,
+ Result.getInt(), Info.Ctx), E);
+ }
+
+ // FIXME: Clean this up!
+ if (SrcType->isPointerType()) {
+ APValue LV;
+ if (!EvaluatePointer(SubExpr, LV, Info))
+ return false;
+
+ if (LV.getLValueBase()) {
+ // Only allow based lvalue casts if they are lossless.
+ if (Info.Ctx.getTypeSize(DestType) != Info.Ctx.getTypeSize(SrcType))
+ return false;
+
+ Result = LV;
+ return true;
+ }
+
+ APSInt AsInt = Info.Ctx.MakeIntValue(LV.getLValueOffset().getQuantity(),
+ SrcType);
+ return Success(HandleIntToIntCast(DestType, SrcType, AsInt, Info.Ctx), E);
+ }
+
+ if (SrcType->isArrayType() || SrcType->isFunctionType()) {
+ // This handles double-conversion cases, where there's both
+ // an l-value promotion and an implicit conversion to int.
+ APValue LV;
+ if (!EvaluateLValue(SubExpr, LV, Info))
+ return false;
+
+ if (Info.Ctx.getTypeSize(DestType) != Info.Ctx.getTypeSize(Info.Ctx.VoidPtrTy))
+ return false;
+
+ Result = LV;
+ return true;
+ }
+
+ if (SrcType->isAnyComplexType()) {
+ APValue C;
+ if (!EvaluateComplex(SubExpr, C, Info))
+ return false;
+ if (C.isComplexFloat())
+ return Success(HandleFloatToIntCast(DestType, SrcType,
+ C.getComplexFloatReal(), Info.Ctx),
+ E);
+ else
+ return Success(HandleIntToIntCast(DestType, SrcType,
+ C.getComplexIntReal(), Info.Ctx), E);
+ }
+ // FIXME: Handle vectors
+
+ if (!SrcType->isRealFloatingType())
+ return Error(E->getExprLoc(), diag::note_invalid_subexpr_in_ice, E);
+
+ APFloat F(0.0);
+ if (!EvaluateFloat(SubExpr, F, Info))
+ return Error(E->getExprLoc(), diag::note_invalid_subexpr_in_ice, E);
+
+ return Success(HandleFloatToIntCast(DestType, SrcType, F, Info.Ctx), E);
+}
+
+bool IntExprEvaluator::VisitUnaryReal(const UnaryOperator *E) {
+ if (E->getSubExpr()->getType()->isAnyComplexType()) {
+ APValue LV;
+ if (!EvaluateComplex(E->getSubExpr(), LV, Info) || !LV.isComplexInt())
+ return Error(E->getExprLoc(), diag::note_invalid_subexpr_in_ice, E);
+ return Success(LV.getComplexIntReal(), E);
+ }
+
+ return Visit(E->getSubExpr());
+}
+
+bool IntExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
+ if (E->getSubExpr()->getType()->isComplexIntegerType()) {
+ APValue LV;
+ if (!EvaluateComplex(E->getSubExpr(), LV, Info) || !LV.isComplexInt())
+ return Error(E->getExprLoc(), diag::note_invalid_subexpr_in_ice, E);
+ return Success(LV.getComplexIntImag(), E);
+ }
+
+ if (!E->getSubExpr()->isEvaluatable(Info.Ctx))
+ Info.EvalResult.HasSideEffects = true;
+ return Success(0, E);
+}
+
+//===----------------------------------------------------------------------===//
+// Float Evaluation
+//===----------------------------------------------------------------------===//
+
+namespace {
+class FloatExprEvaluator
+ : public StmtVisitor<FloatExprEvaluator, bool> {
+ EvalInfo &Info;
+ APFloat &Result;
+public:
+ FloatExprEvaluator(EvalInfo &info, APFloat &result)
+ : Info(info), Result(result) {}
+
+ bool VisitStmt(Stmt *S) {
+ return false;
+ }
+
+ bool VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); }
+ bool VisitCallExpr(const CallExpr *E);
+
+ bool VisitUnaryOperator(const UnaryOperator *E);
+ bool VisitBinaryOperator(const BinaryOperator *E);
+ bool VisitFloatingLiteral(const FloatingLiteral *E);
+ bool VisitCastExpr(CastExpr *E);
+ bool VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E);
+ bool VisitConditionalOperator(ConditionalOperator *E);
+
+ bool VisitChooseExpr(const ChooseExpr *E)
+ { return Visit(E->getChosenSubExpr(Info.Ctx)); }
+ bool VisitUnaryExtension(const UnaryOperator *E)
+ { return Visit(E->getSubExpr()); }
+
+ // FIXME: Missing: __real__/__imag__, array subscript of vector,
+ // member of vector, ImplicitValueInitExpr
+};
+} // end anonymous namespace
+
+static bool EvaluateFloat(const Expr* E, APFloat& Result, EvalInfo &Info) {
+ return FloatExprEvaluator(Info, Result).Visit(const_cast<Expr*>(E));
+}
+
+bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) {
+ switch (E->isBuiltinCall(Info.Ctx)) {
+ default: return false;
+ case Builtin::BI__builtin_huge_val:
+ case Builtin::BI__builtin_huge_valf:
+ case Builtin::BI__builtin_huge_vall:
+ case Builtin::BI__builtin_inf:
+ case Builtin::BI__builtin_inff:
+ case Builtin::BI__builtin_infl: {
+ const llvm::fltSemantics &Sem =
+ Info.Ctx.getFloatTypeSemantics(E->getType());
+ Result = llvm::APFloat::getInf(Sem);
+ return true;
+ }
+
+ case Builtin::BI__builtin_nan:
+ case Builtin::BI__builtin_nanf:
+ case Builtin::BI__builtin_nanl:
+ // If this is __builtin_nan() turn this into a nan, otherwise we
+ // can't constant fold it.
+ if (const StringLiteral *S =
+ dyn_cast<StringLiteral>(E->getArg(0)->IgnoreParenCasts())) {
+ if (!S->isWide()) {
+ const llvm::fltSemantics &Sem =
+ Info.Ctx.getFloatTypeSemantics(E->getType());
+ unsigned Type = 0;
+ if (!S->getString().empty() && S->getString().getAsInteger(0, Type))
+ return false;
+ Result = llvm::APFloat::getNaN(Sem, false, Type);
+ return true;
+ }
+ }
+ return false;
+
+ case Builtin::BI__builtin_fabs:
+ case Builtin::BI__builtin_fabsf:
+ case Builtin::BI__builtin_fabsl:
+ if (!EvaluateFloat(E->getArg(0), Result, Info))
+ return false;
+
+ if (Result.isNegative())
+ Result.changeSign();
+ return true;
+
+ case Builtin::BI__builtin_copysign:
+ case Builtin::BI__builtin_copysignf:
+ case Builtin::BI__builtin_copysignl: {
+ APFloat RHS(0.);
+ if (!EvaluateFloat(E->getArg(0), Result, Info) ||
+ !EvaluateFloat(E->getArg(1), RHS, Info))
+ return false;
+ Result.copySign(RHS);
+ return true;
+ }
+ }
+}
+
+bool FloatExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
+ if (E->getOpcode() == UnaryOperator::Deref)
+ return false;
+
+ if (!EvaluateFloat(E->getSubExpr(), Result, Info))
+ return false;
+
+ switch (E->getOpcode()) {
+ default: return false;
+ case UnaryOperator::Plus:
+ return true;
+ case UnaryOperator::Minus:
+ Result.changeSign();
+ return true;
+ }
+}
+
+bool FloatExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
+ if (E->getOpcode() == BinaryOperator::Comma) {
+ if (!EvaluateFloat(E->getRHS(), Result, Info))
+ return false;
+
+ // If we can't evaluate the LHS, it might have side effects;
+ // conservatively mark it.
+ if (!E->getLHS()->isEvaluatable(Info.Ctx))
+ Info.EvalResult.HasSideEffects = true;
+
+ return true;
+ }
+
+ // FIXME: Diagnostics? I really don't understand how the warnings
+ // and errors are supposed to work.
+ APFloat RHS(0.0);
+ if (!EvaluateFloat(E->getLHS(), Result, Info))
+ return false;
+ if (!EvaluateFloat(E->getRHS(), RHS, Info))
+ return false;
+
+ switch (E->getOpcode()) {
+ default: return false;
+ case BinaryOperator::Mul:
+ Result.multiply(RHS, APFloat::rmNearestTiesToEven);
+ return true;
+ case BinaryOperator::Add:
+ Result.add(RHS, APFloat::rmNearestTiesToEven);
+ return true;
+ case BinaryOperator::Sub:
+ Result.subtract(RHS, APFloat::rmNearestTiesToEven);
+ return true;
+ case BinaryOperator::Div:
+ Result.divide(RHS, APFloat::rmNearestTiesToEven);
+ return true;
+ }
+}
+
+bool FloatExprEvaluator::VisitFloatingLiteral(const FloatingLiteral *E) {
+ Result = E->getValue();
+ return true;
+}
+
+bool FloatExprEvaluator::VisitCastExpr(CastExpr *E) {
+ Expr* SubExpr = E->getSubExpr();
+
+ if (SubExpr->getType()->isIntegralType()) {
+ APSInt IntResult;
+ if (!EvaluateInteger(SubExpr, IntResult, Info))
+ return false;
+ Result = HandleIntToFloatCast(E->getType(), SubExpr->getType(),
+ IntResult, Info.Ctx);
+ return true;
+ }
+ if (SubExpr->getType()->isRealFloatingType()) {
+ if (!Visit(SubExpr))
+ return false;
+ Result = HandleFloatToFloatCast(E->getType(), SubExpr->getType(),
+ Result, Info.Ctx);
+ return true;
+ }
+ // FIXME: Handle complex types
+
+ return false;
+}
+
+bool FloatExprEvaluator::VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E) {
+ Result = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(E->getType()));
+ return true;
+}
+
+bool FloatExprEvaluator::VisitConditionalOperator(ConditionalOperator *E) {
+ bool Cond;
+ if (!HandleConversionToBool(E->getCond(), Cond, Info))
+ return false;
+
+ return Visit(Cond ? E->getTrueExpr() : E->getFalseExpr());
+}
+
+//===----------------------------------------------------------------------===//
+// Complex Evaluation (for float and integer)
+//===----------------------------------------------------------------------===//
+
+namespace {
+class ComplexExprEvaluator
+ : public StmtVisitor<ComplexExprEvaluator, APValue> {
+ EvalInfo &Info;
+
+public:
+ ComplexExprEvaluator(EvalInfo &info) : Info(info) {}
+
+ //===--------------------------------------------------------------------===//
+ // Visitor Methods
+ //===--------------------------------------------------------------------===//
+
+ APValue VisitStmt(Stmt *S) {
+ return APValue();
+ }
+
+ APValue VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); }
+
+ APValue VisitImaginaryLiteral(ImaginaryLiteral *E) {
+ Expr* SubExpr = E->getSubExpr();
+
+ if (SubExpr->getType()->isRealFloatingType()) {
+ APFloat Result(0.0);
+
+ if (!EvaluateFloat(SubExpr, Result, Info))
+ return APValue();
+
+ return APValue(APFloat(Result.getSemantics(), APFloat::fcZero, false),
+ Result);
+ } else {
+ assert(SubExpr->getType()->isIntegerType() &&
+ "Unexpected imaginary literal.");
+
+ llvm::APSInt Result;
+ if (!EvaluateInteger(SubExpr, Result, Info))
+ return APValue();
+
+ llvm::APSInt Zero(Result.getBitWidth(), !Result.isSigned());
+ Zero = 0;
+ return APValue(Zero, Result);
+ }
+ }
+
+ APValue VisitCastExpr(CastExpr *E) {
+ Expr* SubExpr = E->getSubExpr();
+ QualType EltType = E->getType()->getAs<ComplexType>()->getElementType();
+ QualType SubType = SubExpr->getType();
+
+ if (SubType->isRealFloatingType()) {
+ APFloat Result(0.0);
+
+ if (!EvaluateFloat(SubExpr, Result, Info))
+ return APValue();
+
+ if (EltType->isRealFloatingType()) {
+ Result = HandleFloatToFloatCast(EltType, SubType, Result, Info.Ctx);
+ return APValue(Result,
+ APFloat(Result.getSemantics(), APFloat::fcZero, false));
+ } else {
+ llvm::APSInt IResult;
+ IResult = HandleFloatToIntCast(EltType, SubType, Result, Info.Ctx);
+ llvm::APSInt Zero(IResult.getBitWidth(), !IResult.isSigned());
+ Zero = 0;
+ return APValue(IResult, Zero);
+ }
+ } else if (SubType->isIntegerType()) {
+ APSInt Result;
+
+ if (!EvaluateInteger(SubExpr, Result, Info))
+ return APValue();
+
+ if (EltType->isRealFloatingType()) {
+ APFloat FResult =
+ HandleIntToFloatCast(EltType, SubType, Result, Info.Ctx);
+ return APValue(FResult,
+ APFloat(FResult.getSemantics(), APFloat::fcZero, false));
+ } else {
+ Result = HandleIntToIntCast(EltType, SubType, Result, Info.Ctx);
+ llvm::APSInt Zero(Result.getBitWidth(), !Result.isSigned());
+ Zero = 0;
+ return APValue(Result, Zero);
+ }
+ } else if (const ComplexType *CT = SubType->getAs<ComplexType>()) {
+ APValue Src;
+
+ if (!EvaluateComplex(SubExpr, Src, Info))
+ return APValue();
+
+ QualType SrcType = CT->getElementType();
+
+ if (Src.isComplexFloat()) {
+ if (EltType->isRealFloatingType()) {
+ return APValue(HandleFloatToFloatCast(EltType, SrcType,
+ Src.getComplexFloatReal(),
+ Info.Ctx),
+ HandleFloatToFloatCast(EltType, SrcType,
+ Src.getComplexFloatImag(),
+ Info.Ctx));
+ } else {
+ return APValue(HandleFloatToIntCast(EltType, SrcType,
+ Src.getComplexFloatReal(),
+ Info.Ctx),
+ HandleFloatToIntCast(EltType, SrcType,
+ Src.getComplexFloatImag(),
+ Info.Ctx));
+ }
+ } else {
+ assert(Src.isComplexInt() && "Invalid evaluate result.");
+ if (EltType->isRealFloatingType()) {
+ return APValue(HandleIntToFloatCast(EltType, SrcType,
+ Src.getComplexIntReal(),
+ Info.Ctx),
+ HandleIntToFloatCast(EltType, SrcType,
+ Src.getComplexIntImag(),
+ Info.Ctx));
+ } else {
+ return APValue(HandleIntToIntCast(EltType, SrcType,
+ Src.getComplexIntReal(),
+ Info.Ctx),
+ HandleIntToIntCast(EltType, SrcType,
+ Src.getComplexIntImag(),
+ Info.Ctx));
+ }
+ }
+ }
+
+ // FIXME: Handle more casts.
+ return APValue();
+ }
+
+ APValue VisitBinaryOperator(const BinaryOperator *E);
+ APValue VisitChooseExpr(const ChooseExpr *E)
+ { return Visit(E->getChosenSubExpr(Info.Ctx)); }
+ APValue VisitUnaryExtension(const UnaryOperator *E)
+ { return Visit(E->getSubExpr()); }
+ // FIXME Missing: unary +/-/~, binary div, ImplicitValueInitExpr,
+ // conditional ?:, comma
+};
+} // end anonymous namespace
+
+static bool EvaluateComplex(const Expr *E, APValue &Result, EvalInfo &Info) {
+ Result = ComplexExprEvaluator(Info).Visit(const_cast<Expr*>(E));
+ assert((!Result.isComplexFloat() ||
+ (&Result.getComplexFloatReal().getSemantics() ==
+ &Result.getComplexFloatImag().getSemantics())) &&
+ "Invalid complex evaluation.");
+ return Result.isComplexFloat() || Result.isComplexInt();
+}
+
+APValue ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
+ APValue Result, RHS;
+
+ if (!EvaluateComplex(E->getLHS(), Result, Info))
+ return APValue();
+
+ if (!EvaluateComplex(E->getRHS(), RHS, Info))
+ return APValue();
+
+ assert(Result.isComplexFloat() == RHS.isComplexFloat() &&
+ "Invalid operands to binary operator.");
+ switch (E->getOpcode()) {
+ default: return APValue();
+ case BinaryOperator::Add:
+ if (Result.isComplexFloat()) {
+ Result.getComplexFloatReal().add(RHS.getComplexFloatReal(),
+ APFloat::rmNearestTiesToEven);
+ Result.getComplexFloatImag().add(RHS.getComplexFloatImag(),
+ APFloat::rmNearestTiesToEven);
+ } else {
+ Result.getComplexIntReal() += RHS.getComplexIntReal();
+ Result.getComplexIntImag() += RHS.getComplexIntImag();
+ }
+ break;
+ case BinaryOperator::Sub:
+ if (Result.isComplexFloat()) {
+ Result.getComplexFloatReal().subtract(RHS.getComplexFloatReal(),
+ APFloat::rmNearestTiesToEven);
+ Result.getComplexFloatImag().subtract(RHS.getComplexFloatImag(),
+ APFloat::rmNearestTiesToEven);
+ } else {
+ Result.getComplexIntReal() -= RHS.getComplexIntReal();
+ Result.getComplexIntImag() -= RHS.getComplexIntImag();
+ }
+ break;
+ case BinaryOperator::Mul:
+ if (Result.isComplexFloat()) {
+ APValue LHS = Result;
+ APFloat &LHS_r = LHS.getComplexFloatReal();
+ APFloat &LHS_i = LHS.getComplexFloatImag();
+ APFloat &RHS_r = RHS.getComplexFloatReal();
+ APFloat &RHS_i = RHS.getComplexFloatImag();
+
+ APFloat Tmp = LHS_r;
+ Tmp.multiply(RHS_r, APFloat::rmNearestTiesToEven);
+ Result.getComplexFloatReal() = Tmp;
+ Tmp = LHS_i;
+ Tmp.multiply(RHS_i, APFloat::rmNearestTiesToEven);
+ Result.getComplexFloatReal().subtract(Tmp, APFloat::rmNearestTiesToEven);
+
+ Tmp = LHS_r;
+ Tmp.multiply(RHS_i, APFloat::rmNearestTiesToEven);
+ Result.getComplexFloatImag() = Tmp;
+ Tmp = LHS_i;
+ Tmp.multiply(RHS_r, APFloat::rmNearestTiesToEven);
+ Result.getComplexFloatImag().add(Tmp, APFloat::rmNearestTiesToEven);
+ } else {
+ APValue LHS = Result;
+ Result.getComplexIntReal() =
+ (LHS.getComplexIntReal() * RHS.getComplexIntReal() -
+ LHS.getComplexIntImag() * RHS.getComplexIntImag());
+ Result.getComplexIntImag() =
+ (LHS.getComplexIntReal() * RHS.getComplexIntImag() +
+ LHS.getComplexIntImag() * RHS.getComplexIntReal());
+ }
+ break;
+ }
+
+ return Result;
+}
+
+//===----------------------------------------------------------------------===//
+// Top level Expr::Evaluate method.
+//===----------------------------------------------------------------------===//
+
+/// Evaluate - Return true if this is a constant which we can fold using
+/// any crazy technique (that has nothing to do with language standards) that
+/// we want to. If this function returns true, it returns the folded constant
+/// in Result.
+bool Expr::Evaluate(EvalResult &Result, ASTContext &Ctx) const {
+ EvalInfo Info(Ctx, Result);
+
+ if (getType()->isVectorType()) {
+ if (!EvaluateVector(this, Result.Val, Info))
+ return false;
+ } else if (getType()->isIntegerType()) {
+ if (!IntExprEvaluator(Info, Result.Val).Visit(const_cast<Expr*>(this)))
+ return false;
+ } else if (getType()->hasPointerRepresentation()) {
+ if (!EvaluatePointer(this, Result.Val, Info))
+ return false;
+ } else if (getType()->isRealFloatingType()) {
+ llvm::APFloat f(0.0);
+ if (!EvaluateFloat(this, f, Info))
+ return false;
+
+ Result.Val = APValue(f);
+ } else if (getType()->isAnyComplexType()) {
+ if (!EvaluateComplex(this, Result.Val, Info))
+ return false;
+ } else
+ return false;
+
+ return true;
+}
+
+bool Expr::EvaluateAsAny(EvalResult &Result, ASTContext &Ctx) const {
+ EvalInfo Info(Ctx, Result, true);
+
+ if (getType()->isVectorType()) {
+ if (!EvaluateVector(this, Result.Val, Info))
+ return false;
+ } else if (getType()->isIntegerType()) {
+ if (!IntExprEvaluator(Info, Result.Val).Visit(const_cast<Expr*>(this)))
+ return false;
+ } else if (getType()->hasPointerRepresentation()) {
+ if (!EvaluatePointer(this, Result.Val, Info))
+ return false;
+ } else if (getType()->isRealFloatingType()) {
+ llvm::APFloat f(0.0);
+ if (!EvaluateFloat(this, f, Info))
+ return false;
+
+ Result.Val = APValue(f);
+ } else if (getType()->isAnyComplexType()) {
+ if (!EvaluateComplex(this, Result.Val, Info))
+ return false;
+ } else
+ return false;
+
+ return true;
+}
+
+bool Expr::EvaluateAsBooleanCondition(bool &Result, ASTContext &Ctx) const {
+ EvalResult Scratch;
+ EvalInfo Info(Ctx, Scratch);
+
+ return HandleConversionToBool(this, Result, Info);
+}
+
+bool Expr::EvaluateAsLValue(EvalResult &Result, ASTContext &Ctx) const {
+ EvalInfo Info(Ctx, Result);
+
+ return EvaluateLValue(this, Result.Val, Info) && !Result.HasSideEffects;
+}
+
+bool Expr::EvaluateAsAnyLValue(EvalResult &Result, ASTContext &Ctx) const {
+ EvalInfo Info(Ctx, Result, true);
+
+ return EvaluateLValue(this, Result.Val, Info) && !Result.HasSideEffects;
+}
+
+/// isEvaluatable - Call Evaluate to see if this expression can be constant
+/// folded, but discard the result.
+bool Expr::isEvaluatable(ASTContext &Ctx) const {
+ EvalResult Result;
+ return Evaluate(Result, Ctx) && !Result.HasSideEffects;
+}
+
+bool Expr::HasSideEffects(ASTContext &Ctx) const {
+ Expr::EvalResult Result;
+ EvalInfo Info(Ctx, Result);
+ return HasSideEffect(Info).Visit(const_cast<Expr*>(this));
+}
+
+APSInt Expr::EvaluateAsInt(ASTContext &Ctx) const {
+ EvalResult EvalResult;
+ bool Result = Evaluate(EvalResult, Ctx);
+ Result = Result;
+ assert(Result && "Could not evaluate expression");
+ assert(EvalResult.Val.isInt() && "Expression did not evaluate to integer");
+
+ return EvalResult.Val.getInt();
+}