diff options
| -rw-r--r-- | lib/AST/ExprConstant.cpp | 164 | ||||
| -rw-r--r-- | test/SemaCXX/constant-expression-cxx11.cpp | 671 | ||||
| -rw-r--r-- | test/SemaCXX/constexpr-ackermann.cpp | 8 | ||||
| -rw-r--r-- | test/SemaCXX/constexpr-factorial.cpp | 9 | ||||
| -rw-r--r-- | test/SemaCXX/constexpr-nqueens.cpp | 76 |
5 files changed, 882 insertions, 46 deletions
diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp index 25c7a90caa..75f32ab5d4 100644 --- a/lib/AST/ExprConstant.cpp +++ b/lib/AST/ExprConstant.cpp @@ -810,6 +810,21 @@ static bool IsConstNonVolatile(QualType T) { return Quals.hasConst() && !Quals.hasVolatile(); } +/// Get the base index of the given base class within an APValue representing +/// the given derived class. +static unsigned getBaseIndex(const CXXRecordDecl *Derived, + const CXXRecordDecl *Base) { + Base = Base->getCanonicalDecl(); + unsigned Index = 0; + for (CXXRecordDecl::base_class_const_iterator I = Derived->bases_begin(), + E = Derived->bases_end(); I != E; ++I, ++Index) { + if (I->getType()->getAsCXXRecordDecl()->getCanonicalDecl() == Base) + return Index; + } + + llvm_unreachable("base class missing from derived class's bases list"); +} + /// Extract the designated sub-object of an rvalue. static bool ExtractSubobject(EvalInfo &Info, CCValue &Obj, QualType ObjType, const SubobjectDesignator &Sub, QualType SubType) { @@ -852,22 +867,10 @@ static bool ExtractSubobject(EvalInfo &Info, CCValue &Obj, QualType ObjType, ObjType = Field->getType(); } else { // Next subobject is a base class. - const CXXRecordDecl *RD = - cast<CXXRecordDecl>(ObjType->castAs<RecordType>()->getDecl()); - const CXXRecordDecl *Base = - getAsBaseClass(Sub.Entries[I])->getCanonicalDecl(); - unsigned Index = 0; - for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(), - E = RD->bases_end(); I != E; ++I, ++Index) { - QualType BT = I->getType(); - if (BT->castAs<RecordType>()->getDecl()->getCanonicalDecl() == Base) { - O = &O->getStructBase(Index); - ObjType = BT; - break; - } - } - if (Index == RD->getNumBases()) - return false; + const CXXRecordDecl *Derived = ObjType->getAsCXXRecordDecl(); + const CXXRecordDecl *Base = getAsBaseClass(Sub.Entries[I]); + O = &O->getStructBase(getBaseIndex(Derived, Base)); + ObjType = Info.Ctx.getRecordType(Base); } if (O->isUninit()) @@ -974,6 +977,21 @@ static bool HandleLValueToRValueConversion(EvalInfo &Info, QualType Type, return ExtractSubobject(Info, RVal, Base->getType(), LVal.Designator, Type); } +/// Build an lvalue for the object argument of a member function call. +static bool EvaluateObjectArgument(EvalInfo &Info, const Expr *Object, + LValue &This) { + if (Object->getType()->isPointerType()) + return EvaluatePointer(Object, This, Info); + + if (Object->isGLValue()) + return EvaluateLValue(Object, This, Info); + + // Implicitly promote a prvalue *this object to a glvalue. + This.setExpr(Object, Info.CurrentCall); + return EvaluateConstantExpression(Info.CurrentCall->Temporaries[Object], Info, + This, Object); +} + namespace { enum EvalStmtResult { /// Evaluation failed. @@ -1029,8 +1047,9 @@ static bool EvaluateArgs(ArrayRef<const Expr*> Args, ArgVector &ArgValues, } /// Evaluate a function call. -static bool HandleFunctionCall(ArrayRef<const Expr*> Args, const Stmt *Body, - EvalInfo &Info, CCValue &Result) { +static bool HandleFunctionCall(const LValue *This, ArrayRef<const Expr*> Args, + const Stmt *Body, EvalInfo &Info, + CCValue &Result) { // FIXME: Implement a proper call limit, along with a command-line flag. if (Info.NumCalls >= 1000000 || Info.CallStackDepth >= 512) return false; @@ -1039,16 +1058,15 @@ static bool HandleFunctionCall(ArrayRef<const Expr*> Args, const Stmt *Body, if (!EvaluateArgs(Args, ArgValues, Info)) return false; - // FIXME: Pass in 'this' for member functions. - const LValue *This = 0; CallStackFrame Frame(Info, This, ArgValues.data()); return EvaluateStmt(Result, Info, Body) == ESR_Returned; } /// Evaluate a constructor call. -static bool HandleConstructorCall(ArrayRef<const Expr*> Args, +static bool HandleConstructorCall(const LValue &This, + ArrayRef<const Expr*> Args, const CXXConstructorDecl *Definition, - EvalInfo &Info, const LValue &This, + EvalInfo &Info, APValue &Result) { if (Info.NumCalls >= 1000000 || Info.CallStackDepth >= 512) return false; @@ -1305,39 +1323,61 @@ public: const Expr *Callee = E->getCallee(); QualType CalleeType = Callee->getType(); - // FIXME: Handle the case where Callee is a (parenthesized) MemberExpr for a - // non-static member function. - if (CalleeType->isSpecificBuiltinType(BuiltinType::BoundMember)) - return DerivedError(E); - - if (!CalleeType->isFunctionType() && !CalleeType->isFunctionPointerType()) - return DerivedError(E); - - CCValue Call; - if (!Evaluate(Call, Info, Callee) || !Call.isLValue() || - !Call.getLValueBase() || !Call.getLValueOffset().isZero()) - return DerivedError(Callee); - const FunctionDecl *FD = 0; - if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Call.getLValueBase())) - FD = dyn_cast<FunctionDecl>(DRE->getDecl()); - else if (const MemberExpr *ME = dyn_cast<MemberExpr>(Call.getLValueBase())) + LValue *This = 0, ThisVal; + llvm::ArrayRef<const Expr*> Args(E->getArgs(), E->getNumArgs()); + + // Extract function decl and 'this' pointer from the callee. + if (CalleeType->isSpecificBuiltinType(BuiltinType::BoundMember)) { + // Explicit bound member calls, such as x.f() or p->g(); + // FIXME: Handle a BinaryOperator callee ('.*' or '->*'). + const MemberExpr *ME = dyn_cast<MemberExpr>(Callee->IgnoreParens()); + if (!ME) + return DerivedError(Callee); + if (!EvaluateObjectArgument(Info, ME->getBase(), ThisVal)) + return DerivedError(ME->getBase()); + This = &ThisVal; FD = dyn_cast<FunctionDecl>(ME->getMemberDecl()); - if (!FD) - return DerivedError(Callee); + if (!FD) + return DerivedError(ME); + } else if (CalleeType->isFunctionPointerType()) { + CCValue Call; + if (!Evaluate(Call, Info, Callee) || !Call.isLValue() || + !Call.getLValueBase() || !Call.getLValueOffset().isZero()) + return DerivedError(Callee); + + const Expr *Base = Call.getLValueBase(); + + if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Base)) + FD = dyn_cast<FunctionDecl>(DRE->getDecl()); + else if (const MemberExpr *ME = dyn_cast<MemberExpr>(Base)) + FD = dyn_cast<FunctionDecl>(ME->getMemberDecl()); + if (!FD) + return DerivedError(Callee); + + // Overloaded operator calls to member functions are represented as normal + // calls with '*this' as the first argument. + const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD); + if (MD && !MD->isStatic()) { + if (!EvaluateObjectArgument(Info, Args[0], ThisVal)) + return false; + This = &ThisVal; + Args = Args.slice(1); + } - // Don't call function pointers which have been cast to some other type. - if (!Info.Ctx.hasSameType(CalleeType->getPointeeType(), FD->getType())) + // Don't call function pointers which have been cast to some other type. + if (!Info.Ctx.hasSameType(CalleeType->getPointeeType(), FD->getType())) + return DerivedError(E); + } else return DerivedError(E); const FunctionDecl *Definition; Stmt *Body = FD->getBody(Definition); CCValue CCResult; APValue Result; - llvm::ArrayRef<const Expr*> Args(E->getArgs(), E->getNumArgs()); if (Body && Definition->isConstexpr() && !Definition->isInvalidDecl() && - HandleFunctionCall(Args, Body, Info, CCResult) && + HandleFunctionCall(This, Args, Body, Info, CCResult) && CheckConstantExpression(CCResult, Result)) return DerivedSuccess(CCValue(Result, CCValue::GlobalValue()), E); @@ -1821,11 +1861,43 @@ namespace { } bool Error(const Expr *E) { return false; } + bool VisitCastExpr(const CastExpr *E); bool VisitInitListExpr(const InitListExpr *E); bool VisitCXXConstructExpr(const CXXConstructExpr *E); }; } +bool RecordExprEvaluator::VisitCastExpr(const CastExpr *E) { + switch (E->getCastKind()) { + default: + return ExprEvaluatorBaseTy::VisitCastExpr(E); + + case CK_ConstructorConversion: + return Visit(E->getSubExpr()); + + case CK_DerivedToBase: + case CK_UncheckedDerivedToBase: { + CCValue DerivedObject; + if (!Evaluate(DerivedObject, Info, E->getSubExpr()) || + !DerivedObject.isStruct()) + return false; + + // Derived-to-base rvalue conversion: just slice off the derived part. + APValue *Value = &DerivedObject; + const CXXRecordDecl *RD = E->getSubExpr()->getType()->getAsCXXRecordDecl(); + for (CastExpr::path_const_iterator PathI = E->path_begin(), + PathE = E->path_end(); PathI != PathE; ++PathI) { + assert(!(*PathI)->isVirtual() && "record rvalue with virtual base"); + const CXXRecordDecl *Base = (*PathI)->getType()->getAsCXXRecordDecl(); + Value = &Value->getStructBase(getBaseIndex(RD, Base)); + RD = Base; + } + Result = *Value; + return true; + } + } +} + bool RecordExprEvaluator::VisitInitListExpr(const InitListExpr *E) { const RecordDecl *RD = E->getType()->castAs<RecordType>()->getDecl(); const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); @@ -1890,8 +1962,8 @@ bool RecordExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E) { return Visit(ME->GetTemporaryExpr()); llvm::ArrayRef<const Expr*> Args(E->getArgs(), E->getNumArgs()); - return HandleConstructorCall(Args, cast<CXXConstructorDecl>(Definition), - Info, This, Result); + return HandleConstructorCall(This, Args, cast<CXXConstructorDecl>(Definition), + Info, Result); } static bool EvaluateRecord(const Expr *E, const LValue &This, diff --git a/test/SemaCXX/constant-expression-cxx11.cpp b/test/SemaCXX/constant-expression-cxx11.cpp new file mode 100644 index 0000000000..c1d4a1109a --- /dev/null +++ b/test/SemaCXX/constant-expression-cxx11.cpp @@ -0,0 +1,671 @@ +// RUN: %clang_cc1 -triple i686-linux -fsyntax-only -verify -std=c++11 %s + +// This version of static_assert just requires a foldable value as the +// expression, not an ICE. +// FIXME: Once we implement the C++11 ICE rules, most uses of this here should +// be converted to static_assert. +#define static_assert_fold(expr, str) \ + static_assert(__builtin_constant_p(expr), "not an integral constant expression"); \ + static_assert(__builtin_constant_p(expr) ? expr : true, str) + +namespace StaticAssertFoldTest { + +int x; +static_assert_fold(++x, "test"); // expected-error {{not an integral constant expression}} +static_assert_fold(false, "test"); // expected-error {{test}} + +} + +// FIXME: support const T& parameters here. +//template<typename T> constexpr T id(const T &t) { return t; } +template<typename T> constexpr T id(T t) { return t; } +// FIXME: support templates here. +//template<typename T> constexpr T min(const T &a, const T &b) { +// return a < b ? a : b; +//} +//template<typename T> constexpr T max(const T &a, const T &b) { +// return a < b ? b : a; +//} +constexpr int min(const int &a, const int &b) { return a < b ? a : b; } +constexpr int max(const int &a, const int &b) { return a < b ? b : a; } + +struct MemberZero { + constexpr int zero() { return 0; } +}; + +namespace DerivedToVBaseCast { + + struct U { int n; }; + struct V : U { int n; }; + struct A : virtual V { int n; }; + struct Aa { int n; }; + struct B : virtual A, Aa {}; + struct C : virtual A, Aa {}; + struct D : B, C {}; + + D d; + constexpr B *p = &d; + constexpr C *q = &d; + static_assert_fold((void*)p != (void*)q, ""); + static_assert_fold((A*)p == (A*)q, ""); + static_assert_fold((Aa*)p != (Aa*)q, ""); + + constexpr B &pp = d; + constexpr C &qq = d; + static_assert_fold((void*)&pp != (void*)&qq, ""); + static_assert_fold(&(A&)pp == &(A&)qq, ""); + static_assert_fold(&(Aa&)pp != &(Aa&)qq, ""); + + constexpr V *v = p; + constexpr V *w = q; + constexpr V *x = (A*)p; + static_assert_fold(v == w, ""); + static_assert_fold(v == x, ""); + + static_assert_fold((U*)&d == p, ""); + static_assert_fold((U*)&d == q, ""); + static_assert_fold((U*)&d == v, ""); + static_assert_fold((U*)&d == w, ""); + static_assert_fold((U*)&d == x, ""); + + struct X {}; + struct Y1 : virtual X {}; + struct Y2 : X {}; + struct Z : Y1, Y2 {}; + Z z; + static_assert_fold((X*)(Y1*)&z != (X*)(Y2*)&z, ""); + +} + +namespace TemplateArgumentConversion { + template<int n> struct IntParam {}; + + using IntParam0 = IntParam<0>; + // FIXME: This should be accepted once we do constexpr function invocation. + using IntParam0 = IntParam<id(0)>; // expected-error {{not an integral constant expression}} + using IntParam0 = IntParam<MemberZero().zero>; // expected-error {{did you mean to call it with no arguments?}} expected-error {{not an integral constant expression}} +} + +namespace CaseStatements { + void f(int n) { + switch (n) { + // FIXME: Produce the 'add ()' fixit for this. + case MemberZero().zero: // desired-error {{did you mean to call it with no arguments?}} expected-error {{not an integer constant expression}} + // FIXME: This should be accepted once we do constexpr function invocation. + case id(1): // expected-error {{not an integer constant expression}} + return; + } + } +} + +extern int &Recurse1; +int &Recurse2 = Recurse1, &Recurse1 = Recurse2; +constexpr int &Recurse3 = Recurse2; // expected-error {{must be initialized by a constant expression}} + +namespace MemberEnum { + struct WithMemberEnum { + enum E { A = 42 }; + } wme; + + static_assert_fold(wme.A == 42, ""); +} + +namespace DefaultArguments { + +const int z = int(); +constexpr int Sum(int a = 0, const int &b = 0, const int *c = &z, char d = 0) { + return a + b + *c + d; +} +const int four = 4; +constexpr int eight = 8; +constexpr const int twentyseven = 27; +static_assert_fold(Sum() == 0, ""); +static_assert_fold(Sum(1) == 1, ""); +static_assert_fold(Sum(1, four) == 5, ""); +static_assert_fold(Sum(1, eight, &twentyseven) == 36, ""); +static_assert_fold(Sum(1, 2, &four, eight) == 15, ""); + +} + +namespace Ellipsis { + +// Note, values passed through an ellipsis can't actually be used. +constexpr int F(int a, ...) { return a; } +static_assert_fold(F(0) == 0, ""); +static_assert_fold(F(1, 0) == 1, ""); +static_assert_fold(F(2, "test") == 2, ""); +static_assert_fold(F(3, &F) == 3, ""); +int k = 0; +static_assert_fold(F(4, k) == 3, ""); // expected-error {{constant expression}} + +} + +namespace Recursion { + constexpr int fib(int n) { return n > 1 ? fib(n-1) + fib(n-2) : n; } + static_assert_fold(fib(11) == 89, ""); + + constexpr int gcd_inner(int a, int b) { + return b == 0 ? a : gcd_inner(b, a % b); + } + constexpr int gcd(int a, int b) { + return gcd_inner(max(a, b), min(a, b)); + } + + static_assert_fold(gcd(1749237, 5628959) == 7, ""); +} + +namespace FunctionCast { + // When folding, we allow functions to be cast to different types. Such + // cast functions cannot be called, even if they're constexpr. + constexpr int f() { return 1; } + typedef double (*DoubleFn)(); + typedef int (*IntFn)(); + int a[(int)DoubleFn(f)()]; // expected-error {{variable length array}} + int b[(int)IntFn(f)()]; // ok +} + +namespace StaticMemberFunction { + struct S { + static constexpr int k = 42; + static constexpr int f(int n) { return n * k + 2; } + } s; + + constexpr int n = s.f(19); + static_assert_fold(S::f(19) == 800, ""); + static_assert_fold(s.f(19) == 800, ""); + static_assert_fold(n == 800, ""); +} + +namespace ParameterScopes { + + const int k = 42; + constexpr const int &ObscureTheTruth(const int &a) { return a; } + constexpr const int &MaybeReturnJunk(bool b, const int a) { + return ObscureTheTruth(b ? a : k); + } + static_assert_fold(MaybeReturnJunk(false, 0) == 42, ""); // ok + constexpr int a = MaybeReturnJunk(true, 0); // expected-error {{constant expression}} + + constexpr const int MaybeReturnNonstaticRef(bool b, const int a) { + // If ObscureTheTruth returns a reference to 'a', the result is not a + // constant expression even though 'a' is still in scope. + return ObscureTheTruth(b ? a : k); + } + static_assert_fold(MaybeReturnNonstaticRef(false, 0) == 42, ""); // ok + constexpr int b = MaybeReturnNonstaticRef(true, 0); // expected-error {{constant expression}} + + constexpr int InternalReturnJunk(int n) { + // FIXME: We should reject this: it never produces a constant expression. + return MaybeReturnJunk(true, n); + } + constexpr int n3 = InternalReturnJunk(0); // expected-error {{must be initialized by a constant expression}} + + constexpr int LToR(int &n) { return n; } + constexpr int GrabCallersArgument(bool which, int a, int b) { + return LToR(which ? b : a); + } + static_assert_fold(GrabCallersArgument(false, 1, 2) == 1, ""); + static_assert_fold(GrabCallersArgument(true, 4, 8) == 8, ""); + +} + +namespace Pointers { + + constexpr int f(int n, const int *a, const int *b, const int *c) { + return n == 0 ? 0 : *a + f(n-1, b, c, a); + } + + const int x = 1, y = 10, z = 100; + static_assert_fold(f(23, &x, &y, &z) == 788, ""); + + constexpr int g(int n, int a, int b, int c) { + return f(n, &a, &b, &c); + } + static_assert_fold(g(23, x, y, z) == 788, ""); + +} + +namespace FunctionPointers { + + constexpr int Double(int n) { return 2 * n; } + constexpr int Triple(int n) { return 3 * n; } + constexpr int Twice(int (*F)(int), int n) { return F(F(n)); } + constexpr int Quadruple(int n) { return Twice(Double, n); } + constexpr auto Select(int n) -> int (*)(int) { + return n == 2 ? &Double : n == 3 ? &Triple : n == 4 ? &Quadruple : 0; + } + constexpr int Apply(int (*F)(int), int n) { return F(n); } + + static_assert_fold(1 + Apply(Select(4), 5) + Apply(Select(3), 7) == 42, ""); + + constexpr int Invalid = Apply(Select(0), 0); // expected-error {{must be initialized by a constant expression}} + +} + +namespace PointerComparison { + +int x, y; +static_assert_fold(&x == &y, "false"); // expected-error {{false}} +static_assert_fold(&x != &y, ""); +constexpr bool g1 = &x == &y; +constexpr bool g2 = &x != &y; +constexpr bool g3 = &x <= &y; // expected-error {{must be initialized by a constant expression}} +constexpr bool g4 = &x >= &y; // expected-error {{must be initialized by a constant expression}} +constexpr bool g5 = &x < &y; // expected-error {{must be initialized by a constant expression}} +constexpr bool g6 = &x > &y; // expected-error {{must be initialized by a constant expression}} + +struct S { int x, y; } s; +static_assert_fold(&s.x == &s.y, "false"); // expected-error {{false}} +static_assert_fold(&s.x != &s.y, ""); +static_assert_fold(&s.x <= &s.y, ""); +static_assert_fold(&s.x >= &s.y, "false"); // expected-error {{false}} +static_assert_fold(&s.x < &s.y, ""); +static_assert_fold(&s.x > &s.y, "false"); // expected-error {{false}} + +static_assert_fold(0 == &y, "false"); // expected-error {{false}} +static_assert_fold(0 != &y, ""); +constexpr bool n3 = 0 <= &y; // expected-error {{must be initialized by a constant expression}} +constexpr bool n4 = 0 >= &y; // expected-error {{must be initialized by a constant expression}} +constexpr bool n5 = 0 < &y; // expected-error {{must be initialized by a constant expression}} +constexpr bool n6 = 0 > &y; // expected-error {{must be initialized by a constant expression}} + +static_assert_fold(&x == 0, "false"); // expected-error {{false}} +static_assert_fold(&x != 0, ""); +constexpr bool n9 = &x <= 0; // expected-error {{must be initialized by a constant expression}} +constexpr bool n10 = &x >= 0; // expected-error {{must be initialized by a constant expression}} +constexpr bool n11 = &x < 0; // expected-error {{must be initialized by a constant expression}} +constexpr bool n12 = &x > 0; // expected-error {{must be initialized by a constant expression}} + +static_assert_fold(&x == &x, ""); +static_assert_fold(&x != &x, "false"); // expected-error {{false}} +static_assert_fold(&x <= &x, ""); +static_assert_fold(&x >= &x, ""); +static_assert_fold(&x < &x, "false"); // expected-error {{false}} +static_assert_fold(&x > &x, "false"); // expected-error {{false}} + +constexpr S* sptr = &s; +// FIXME: This is not a constant expression; check we reject this and move this +// test elsewhere. +constexpr bool dyncast = sptr == dynamic_cast<S*>(sptr); + +extern char externalvar[]; +// FIXME: This is not a constant expression; check we reject this and move this +// test elsewhere. +constexpr bool constaddress = (void *)externalvar == (void *)0x4000UL; // expected-error {{must be initialized by a constant expression}} +constexpr bool litaddress = "foo" == "foo"; // expected-error {{must be initialized by a constant expression}} expected-warning {{unspecified}} +static_assert_fold(0 != "foo", ""); + +} + +namespace MaterializeTemporary { + +constexpr int f(const int &r) { return r; } +constexpr int n = f(1); + +constexpr bool same(const int &a, const int &b) { return &a == &b; } +constexpr bool sameTemporary(const int &n) { return same(n, n); } + +static_assert_fold(n, ""); +static_assert_fold(!same(4, 4), ""); +static_assert_fold(same(n, n), ""); +static_assert_fold(sameTemporary(9), ""); + +} + +constexpr int strcmp_ce(const char *p, const char *q) { + return (!*p || *p != *q) ? *p - *q : strcmp_ce(p+1, q+1); +} + +namespace StringLiteral { + +// FIXME: Refactor this once we support constexpr templates. +constexpr int MangleChars(const char *p) { + return *p + 3 * (*p ? MangleChars(p+1) : 0); +} +constexpr int MangleChars(const char16_t *p) { + return *p + 3 * (*p ? MangleChars(p+1) : 0); +} +constexpr int MangleChars(const char32_t *p) { + return *p + 3 * (*p ? MangleChars(p+1) : 0); +} + +static_assert_fold(MangleChars("constexpr!") == 1768383, ""); +static_assert_fold(MangleChars(u"constexpr!") == 1768383, ""); +static_assert_fold(MangleChars(U"constexpr!") == 1768383, ""); + +constexpr char c0 = "nought index"[0]; +constexpr char c1 = "nice index"[10]; +constexpr char c2 = "nasty index"[12]; // expected-error {{must be initialized by a constant expression}} expected-warning {{indexes past the end}} +constexpr char c3 = "negative index"[-1]; // expected-error {{must be initialized by a constant expression}} expected-warning {{indexes before the beginning}} +constexpr char c4 = ((char*)(int*)"no reinterpret_casts allowed")[14]; // expected-error {{must be initialized by a constant expression}} + +constexpr const char *p = "test" + 2; +static_assert_fold(*p == 's', ""); + +constexpr const char *max_iter(const char *a, const char *b) { + return *a < *b ? b : a; +} +constexpr const char *max_element(const char *a, const char *b) { + return (a+1 >= b) ? a : max_iter(a, max_element(a+1, b)); +} + +constexpr const char *begin(const char (&arr)[45]) { return arr; } +constexpr const char *end(const char (&arr)[45]) { return arr + 45; } + +constexpr char str[] = "the quick brown fox jumped over the lazy dog"; +constexpr const char *max = max_element(begin(str), end(str)); +static_assert_fold(*max == 'z', ""); +static_assert_fold(max == str + 38, ""); + +static_assert_fold(strcmp_ce("hello world", "hello world") == 0, ""); +static_assert_fold(strcmp_ce("hello world", "hello clang") > 0, ""); +static_assert_fold(strcmp_ce("constexpr", "test") < 0, ""); +static_assert_fold(strcmp_ce("", " ") < 0, ""); + +} + +namespace Array { + +// FIXME: Use templates for these once we support constexpr templates. +constexpr int Sum(const int *begin, const int *end) { + return begin == end ? 0 : *begin + Sum(begin+1, end); +} +constexpr const int *begin(const int (&xs)[5]) { return xs; } +constexpr const int *end(const int (&xs)[5]) { return xs + 5; } + +constexpr int xs[] = { 1, 2, 3, 4, 5 }; +constexpr int ys[] = { 5, 4, 3, 2, 1 }; +constexpr int sum_xs = Sum(begin(xs), end(xs)); +static_assert_fold(sum_xs == 15, ""); + +constexpr int ZipFoldR(int (*F)(int x, int y, int c), int n, + const int *xs, const int *ys, int c) { + return n ? F(*xs, *ys, ZipFoldR(F, n-1, xs+1, ys+1, c)) : c; +} +constexpr int MulAdd(int x, int y, int c) { return x * y + c; } +constexpr int InnerProduct = ZipFoldR(MulAdd, 5, xs, ys, 0); +static_assert_fold(InnerProduct == 35, ""); + +constexpr int SubMul(int x, int y, int c) { return (x - y) * c; } +constexpr int DiffProd = ZipFoldR(SubMul, 2, xs+3, ys+3, 1); +static_assert_fold(DiffProd == 8, ""); +static_assert_fold(ZipFoldR(SubMul, 3, xs+3, ys+3, 1), ""); // expected-error {{constant expression}} + +constexpr const int *p = xs + 3; +constexpr int xs4 = p[1]; // ok +constexpr int xs5 = p[2]; // expected-error {{constant expression}} +constexpr int xs0 = p[-3]; // ok +constexpr int xs_1 = p[-4]; // expected-error {{constant expression}} + +constexpr int zs[2][2][2][2] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 }; +static_assert_fold(zs[0][0][0][0] == 1, ""); +static_assert_fold(zs[1][1][1][1] == 16, ""); +static_assert_fold(zs[0][0][0][2] == 3, ""); // expected-error {{constant expression}} +static_assert_fold((&zs[0][0][0][2])[-1] == 2, ""); +static_assert_fold(**(**(zs + 1) + 1) == 11, ""); +static_assert_fold(*(&(&(*(*&(&zs[2] - 1)[0] + 2 - 2))[2])[-1][-1] + 1) == 11, ""); + +constexpr int arr[40] = { 1, 2, 3, [8] = 4 }; +constexpr int SumNonzero(const int *p) { + return *p + (*p ? SumNonzero(p+1) : 0); +} +constexpr int CountZero(const int *p, const int *q) { + return p == q ? 0 : (*p == 0) + CountZero(p+1, q); +} +static_assert_fold(SumNonzero(arr) == 6, ""); +static_assert_fold(CountZero(arr, arr + 40) == 36, ""); + +} + +namespace DependentValues { + +struct I { int n; typedef I V[10]; }; +I::V x, y; +template<bool B> struct S { + int k; + void f() { + I::V &cells = B ? x : y; + I &i = cells[k]; + switch (i.n) {} + } +}; + +} + +namespace Class { + +struct A { constexpr A(int a, int b) : k(a + b) {} int k; }; +constexpr int fn(const A &a) { return a.k; } +static_assert_fold(fn(A(4,5)) == 9, ""); + +struct B { int n; int m; } constexpr b = { 0, b.n }; // expected-warning {{uninitialized}} +struct C { + constexpr C(C *this_) : m(42), n(this_->m) {} // ok + int m, n; +}; +struct D { + C c; + constexpr D() : c(&c) {} +}; +static_assert_fold(D().c.n == 42, ""); + +struct E { + constexpr E() : p(&p) {} + void *p; +}; +constexpr const E &e1 = E(); // expected-error {{constant expression}} +// This is a constant expression if we elide the copy constructor call, and +// is not a constant expression if we don't! But we do, so it is. +// FIXME: The move constructor is not currently implicitly defined as constexpr. +// We notice this when evaluating an expression which uses it, but not when +// checking its initializer. +constexpr E e2 = E(); // unexpected-error {{constant expression}} +static_assert_fold(e2.p == &e2.p, ""); // unexpected-error {{constant expression}} +// FIXME: We don't pass through the fact that 'this' is ::e3 when checking the +// initializer of this declaration. +constexpr E e3; // unexpected-error {{constant expression}} +static_assert_fold(e3.p == &e3.p, ""); + +extern const class F f; +struct F { + constexpr F() : p(&f.p) {} + const void *p; +}; +constexpr F f = F(); + +struct G { + struct T { + constexpr T(T *p) : u1(), u2(p) {} + union U1 { + constexpr U1() {} + int a, b = 42; + } u1; + union U2 { + constexpr U2(T *p) : c(p->u1.b) {} + int c, d; + } u2; + } t; + constexpr G() : t(&t) {} +} constexpr g; + +static_assert_fold(g.t.u1.a == 42, ""); // expected-error {{constant expression}} +static_assert_fold(g.t.u1.b == 42, ""); +static_assert_fold(g.t.u2.c == 42, ""); +static_assert_fold(g.t.u2.d == 42, ""); // expected-error {{constant expression}} + +struct S { + int a, b; + const S *p; + double d; + const char *q; + + constexpr S(int n, const S *p) : a(5), b(n), p(p), d(n), q("hello") {} +}; + +S global(43, &global); + +static_assert_fold(S(15, &global).b == 15, ""); + +constexpr bool CheckS(const S &s) { + return s.a == 5 && s.b == 27 && s.p == &global && s.d == 27. && s.q[3] == 'l'; +} +static_assert_fold(CheckS(S(27, &global)), ""); + +struct Arr { + char arr[3]; + constexpr Arr() : arr{'x', 'y', 'z'} {} +}; +constexpr int hash(Arr &&a) { + return a.arr[0] + a.arr[1] * 0x100 + a.arr[2] * 0x10000; +} +constexpr int k = hash(Arr()); +static_assert_fold(k == 0x007a7978, ""); + + +struct AggregateInit { + const char &c; + int n; + double d; + int arr[5]; + void *p; +}; + +constexpr AggregateInit agg1 = { "hello"[0] }; + +static_assert_fold(strcmp_ce(&agg1.c, "hello") == 0, ""); +static_assert_fold(agg1.n == 0, ""); +static_assert_fold(agg1.d == 0.0, ""); +static_assert_fold(agg1.arr[-1] == 0, ""); // expected-error {{constant expression}} +static_assert_fold(agg1.arr[0] == 0, ""); +static_assert_fold(agg1.arr[4] == 0, ""); +static_assert_fold(agg1.arr[5] == 0, ""); // expected-error {{constant expression}} +static_assert_fold(agg1.p == nullptr, ""); + +namespace SimpleDerivedClass { + +struct B { + constexpr B(int n) : a(n) {} + int a; +}; +struct D : B { + constexpr D(int n) : B(n) {} +}; +constexpr D d(3); +static_assert_fold(d.a == 3, ""); + +} + +struct Base { + constexpr Base(int a = 42, const char *b = "test") : a(a), b(b) {} + int a; + const char *b; +}; +struct Base2 { + constexpr Base2(const int &r) : r(r) {} + int q = 123; + // FIXME: When we track the global for which we are computing the initializer, + // use a reference here. + //const int &r; + int r; +}; +struct Derived : Base, Base2 { + constexpr Derived() : Base(76), Base2(a) {} + int c = r + b[1]; +}; + +constexpr bool operator==(const Base &a, const Base &b) { + return a.a == b.a && strcmp_ce(a.b, b.b) == 0; +} + +constexpr Base base; +constexpr Base base2(76); +constexpr Derived derived; +static_assert_fold(derived.a == 76, ""); +static_assert_fold(derived.b[2] == 's', ""); +static_assert_fold(derived.c == 76 + 'e', ""); +static_assert_fold(derived.q == 123, ""); +static_assert_fold(derived.r == 76, ""); +static_assert_fold(&derived.r == &derived.a, ""); // expected-error {{}} + +static_assert_fold(!(derived == base), ""); +static_assert_fold(derived == base2, ""); + +} + +namespace Union { + +union U { + int a; + int b; +}; + +constexpr U u[4] = { { .a = 0 }, { .b = 1 }, { .a = 2 }, { .b = 3 } }; +static_assert_fold(u[0].a == 0, ""); +static_assert_fold(u[0].b, ""); // expected-error {{constant expression}} +static_assert_fold(u[1].b == 1, ""); +static_assert_fold((&u[1].b)[1] == 2, ""); // expected-error {{constant expression}} +static_assert_fold(*(&(u[1].b) + 1 + 1) == 3, ""); // expected-error {{constant expression}} +static_assert_fold((&(u[1]) + 1 + 1)->b == 3, ""); + +} + +namespace Complex { + +class complex { + int re, im; +public: + constexpr complex(int re = 0, int im = 0) : re(re), im(im) {} + constexpr complex(const complex &o) : re(o.re), im(o.im) {} + constexpr complex operator-() const { return complex(-re, -im); } + friend constexpr complex operator+(const complex &l, const complex &r) { + return complex(l.re + r.re, l.im + r.im); + } + friend constexpr complex operator-(const complex &l, const complex &r) { + return l + -r; + } + friend constexpr complex operator*(const complex &l, const complex &r) { + return complex(l.re * r.re - l.im * r.im, l.re * r.im + l.im * r.re); + } + friend constexpr bool operator==(const complex &l, const complex &r) { + return l.re == r.re && l.im == r.im; + } + constexpr bool operator!=(const complex &r) const { + return re != r.re || im != r.im; + } + constexpr int real() const { return re; } + constexpr int imag() const { return im; } +}; + +constexpr complex i = complex(0, 1); +constexpr complex k = (3 + 4*i) * (6 - 4*i); +static_assert_fold(complex(1,0).real() == 1, ""); +static_assert_fold(complex(1,0).imag() == 0, ""); +static_assert_fold(((complex)1).imag() == 0, ""); +static_assert_fold(k.real() == 34, ""); +static_assert_fold(k.imag() == 12, ""); +static_assert_fold(k - 34 == 12*i, ""); +static_assert_fold((complex)1 == complex(1), ""); +static_assert_fold((complex)1 != complex(0, 1), ""); +static_assert_fold(complex(1) == complex(1), ""); +static_assert_fold(complex(1) != complex(0, 1), ""); +constexpr complex makeComplex(int re, int im) { return complex(re, im); } +static_assert_fold(makeComplex(1,0) == complex(1), ""); +static_assert_fold(makeComplex(1,0) != complex(0, 1), ""); + +class complex_wrap : public complex { +public: + constexpr complex_wrap(int re, int im = 0) : complex(re, im) {} + constexpr complex_wrap(const complex_wrap &o) : complex(o) {} +}; + +static_assert_fold((complex_wrap)1 == complex(1), ""); +static_assert_fold((complex)1 != complex_wrap(0, 1), ""); +static_assert_fold(complex(1) == complex_wrap(1), ""); +static_assert_fold(complex_wrap(1) != complex(0, 1), ""); +constexpr complex_wrap makeComplexWrap(int re, int im) { + return complex_wrap(re, im); +} +static_assert_fold(makeComplexWrap(1,0) == complex(1), ""); +static_assert_fold(makeComplexWrap(1,0) != complex(0, 1), ""); + +} diff --git a/test/SemaCXX/constexpr-ackermann.cpp b/test/SemaCXX/constexpr-ackermann.cpp new file mode 100644 index 0000000000..c4ea313948 --- /dev/null +++ b/test/SemaCXX/constexpr-ackermann.cpp @@ -0,0 +1,8 @@ +// RUN: %clang_cc1 -std=c++11 -fsyntax-only %s + +constexpr unsigned long long A(unsigned long long m, unsigned long long n) { + return m == 0 ? n + 1 : n == 0 ? A(m-1, 1) : A(m - 1, A(m, n - 1)); +} + +using X = int[A(3,4)]; +using X = int[125]; diff --git a/test/SemaCXX/constexpr-factorial.cpp b/test/SemaCXX/constexpr-factorial.cpp new file mode 100644 index 0000000000..55ac8f26fb --- /dev/null +++ b/test/SemaCXX/constexpr-factorial.cpp @@ -0,0 +1,9 @@ +// RUN: %clang_cc1 -std=c++11 -fsyntax-only %s + +constexpr unsigned oddfac(unsigned n) { + return n == 1 ? 1 : n * oddfac(n-2); +} +constexpr unsigned k = oddfac(999); + +using A = int[k % 256]; +using A = int[73]; diff --git a/test/SemaCXX/constexpr-nqueens.cpp b/test/SemaCXX/constexpr-nqueens.cpp new file mode 100644 index 0000000000..fbf2045efb --- /dev/null +++ b/test/SemaCXX/constexpr-nqueens.cpp @@ -0,0 +1,76 @@ +// RUN: %clang_cc1 -std=c++11 -fsyntax-only %s + +typedef unsigned long uint64_t; + +struct Board { + uint64_t State; + bool Failed; + + constexpr Board() : State(0), Failed(false) {} + constexpr Board(const Board &O) : State(O.State), Failed(O.Failed) {} + constexpr Board(uint64_t State, bool Failed = false) : |