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-rw-r--r--lib/AST/ExprConstant.cpp496
1 files changed, 335 insertions, 161 deletions
diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp
index da093ff22c..11e753c077 100644
--- a/lib/AST/ExprConstant.cpp
+++ b/lib/AST/ExprConstant.cpp
@@ -1,9 +1,8 @@
//===--- 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.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
@@ -44,6 +43,7 @@
#include "clang/AST/StmtVisitor.h"
#include "clang/AST/TypeLoc.h"
#include "clang/Basic/Builtins.h"
+#include "clang/Basic/FixedPoint.h"
#include "clang/Basic/TargetInfo.h"
#include "llvm/Support/SaveAndRestore.h"
#include "llvm/Support/raw_ostream.h"
@@ -613,6 +613,15 @@ namespace {
}
return *this;
}
+
+ OptionalDiagnostic &operator<<(const APFixedPoint &FX) {
+ if (Diag) {
+ SmallVector<char, 32> Buffer;
+ FX.toString(Buffer);
+ *Diag << StringRef(Buffer.data(), Buffer.size());
+ }
+ return *this;
+ }
};
/// A cleanup, and a flag indicating whether it is lifetime-extended.
@@ -707,6 +716,10 @@ namespace {
EvaluatingObject(Decl, {CallIndex, Version}));
}
+ /// If we're currently speculatively evaluating, the outermost call stack
+ /// depth at which we can mutate state, otherwise 0.
+ unsigned SpeculativeEvaluationDepth = 0;
+
/// The current array initialization index, if we're performing array
/// initialization.
uint64_t ArrayInitIndex = -1;
@@ -719,9 +732,6 @@ namespace {
/// fold (not just why it's not strictly a constant expression)?
bool HasFoldFailureDiagnostic;
- /// Whether or not we're currently speculatively evaluating.
- bool IsSpeculativelyEvaluating;
-
/// Whether or not we're in a context where the front end requires a
/// constant value.
bool InConstantContext;
@@ -786,7 +796,7 @@ namespace {
BottomFrame(*this, SourceLocation(), nullptr, nullptr, nullptr),
EvaluatingDecl((const ValueDecl *)nullptr),
EvaluatingDeclValue(nullptr), HasActiveDiagnostic(false),
- HasFoldFailureDiagnostic(false), IsSpeculativelyEvaluating(false),
+ HasFoldFailureDiagnostic(false),
InConstantContext(false), EvalMode(Mode) {}
void setEvaluatingDecl(APValue::LValueBase Base, APValue &Value) {
@@ -814,14 +824,20 @@ namespace {
return false;
}
- CallStackFrame *getCallFrame(unsigned CallIndex) {
- assert(CallIndex && "no call index in getCallFrame");
+ std::pair<CallStackFrame *, unsigned>
+ getCallFrameAndDepth(unsigned CallIndex) {
+ assert(CallIndex && "no call index in getCallFrameAndDepth");
// We will eventually hit BottomFrame, which has Index 1, so Frame can't
// be null in this loop.
+ unsigned Depth = CallStackDepth;
CallStackFrame *Frame = CurrentCall;
- while (Frame->Index > CallIndex)
+ while (Frame->Index > CallIndex) {
Frame = Frame->Caller;
- return (Frame->Index == CallIndex) ? Frame : nullptr;
+ --Depth;
+ }
+ if (Frame->Index == CallIndex)
+ return {Frame, Depth};
+ return {nullptr, 0};
}
bool nextStep(const Stmt *S) {
@@ -1102,12 +1118,12 @@ namespace {
class SpeculativeEvaluationRAII {
EvalInfo *Info = nullptr;
Expr::EvalStatus OldStatus;
- bool OldIsSpeculativelyEvaluating;
+ unsigned OldSpeculativeEvaluationDepth;
void moveFromAndCancel(SpeculativeEvaluationRAII &&Other) {
Info = Other.Info;
OldStatus = Other.OldStatus;
- OldIsSpeculativelyEvaluating = Other.OldIsSpeculativelyEvaluating;
+ OldSpeculativeEvaluationDepth = Other.OldSpeculativeEvaluationDepth;
Other.Info = nullptr;
}
@@ -1116,7 +1132,7 @@ namespace {
return;
Info->EvalStatus = OldStatus;
- Info->IsSpeculativelyEvaluating = OldIsSpeculativelyEvaluating;
+ Info->SpeculativeEvaluationDepth = OldSpeculativeEvaluationDepth;
}
public:
@@ -1125,9 +1141,9 @@ namespace {
SpeculativeEvaluationRAII(
EvalInfo &Info, SmallVectorImpl<PartialDiagnosticAt> *NewDiag = nullptr)
: Info(&Info), OldStatus(Info.EvalStatus),
- OldIsSpeculativelyEvaluating(Info.IsSpeculativelyEvaluating) {
+ OldSpeculativeEvaluationDepth(Info.SpeculativeEvaluationDepth) {
Info.EvalStatus.Diag = NewDiag;
- Info.IsSpeculativelyEvaluating = true;
+ Info.SpeculativeEvaluationDepth = Info.CallStackDepth + 1;
}
SpeculativeEvaluationRAII(const SpeculativeEvaluationRAII &Other) = delete;
@@ -1613,6 +1629,14 @@ static bool EvaluateAtomic(const Expr *E, const LValue *This, APValue &Result,
EvalInfo &Info);
static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result);
+/// Evaluate an integer or fixed point expression into an APResult.
+static bool EvaluateFixedPointOrInteger(const Expr *E, APFixedPoint &Result,
+ EvalInfo &Info);
+
+/// Evaluate only a fixed point expression into an APResult.
+static bool EvaluateFixedPoint(const Expr *E, APFixedPoint &Result,
+ EvalInfo &Info);
+
//===----------------------------------------------------------------------===//
// Misc utilities
//===----------------------------------------------------------------------===//
@@ -1726,6 +1750,8 @@ static bool IsGlobalLValue(APValue::LValueBase B) {
case Expr::CXXTypeidExprClass:
case Expr::CXXUuidofExprClass:
return true;
+ case Expr::ObjCBoxedExprClass:
+ return cast<ObjCBoxedExpr>(E)->isExpressibleAsConstantInitializer();
case Expr::CallExprClass:
return IsStringLiteralCall(cast<CallExpr>(E));
// For GCC compatibility, &&label has static storage duration.
@@ -2027,6 +2053,9 @@ static bool HandleConversionToBool(const APValue &Val, bool &Result) {
case APValue::Int:
Result = Val.getInt().getBoolValue();
return true;
+ case APValue::FixedPoint:
+ Result = Val.getFixedPoint().getBoolValue();
+ return true;
case APValue::Float:
Result = !Val.getFloat().isZero();
return true;
@@ -2668,9 +2697,11 @@ static APSInt extractStringLiteralCharacter(EvalInfo &Info, const Expr *Lit,
}
// Expand a string literal into an array of characters.
-static void expandStringLiteral(EvalInfo &Info, const Expr *Lit,
+//
+// FIXME: This is inefficient; we should probably introduce something similar
+// to the LLVM ConstantDataArray to make this cheaper.
+static void expandStringLiteral(EvalInfo &Info, const StringLiteral *S,
APValue &Result) {
- const StringLiteral *S = cast<StringLiteral>(Lit);
const ConstantArrayType *CAT =
Info.Ctx.getAsConstantArrayType(S->getType());
assert(CAT && "string literal isn't an array");
@@ -2864,18 +2895,6 @@ findSubobject(EvalInfo &Info, const Expr *E, const CompleteObject &Obj,
ObjType = CAT->getElementType();
- // An array object is represented as either an Array APValue or as an
- // LValue which refers to a string literal.
- if (O->isLValue()) {
- assert(I == N - 1 && "extracting subobject of character?");
- assert(!O->hasLValuePath() || O->getLValuePath().empty());
- if (handler.AccessKind != AK_Read)
- expandStringLiteral(Info, O->getLValueBase().get<const Expr *>(),
- *O);
- else
- return handler.foundString(*O, ObjType, Index);
- }
-
if (O->getArrayInitializedElts() > Index)
O = &O->getArrayInitializedElt(Index);
else if (handler.AccessKind != AK_Read) {
@@ -2988,11 +3007,6 @@ struct ExtractSubobjectHandler {
Result = APValue(Value);
return true;
}
- bool foundString(APValue &Subobj, QualType SubobjType, uint64_t Character) {
- Result = APValue(extractStringLiteralCharacter(
- Info, Subobj.getLValueBase().get<const Expr *>(), Character));
- return true;
- }
};
} // end anonymous namespace
@@ -3050,9 +3064,6 @@ struct ModifySubobjectHandler {
Value = NewVal.getFloat();
return true;
}
- bool foundString(APValue &Subobj, QualType SubobjType, uint64_t Character) {
- llvm_unreachable("shouldn't encounter string elements with ExpandArrays");
- }
};
} // end anonymous namespace
@@ -3134,8 +3145,10 @@ static CompleteObject findCompleteObject(EvalInfo &Info, const Expr *E,
}
CallStackFrame *Frame = nullptr;
+ unsigned Depth = 0;
if (LVal.getLValueCallIndex()) {
- Frame = Info.getCallFrame(LVal.getLValueCallIndex());
+ std::tie(Frame, Depth) =
+ Info.getCallFrameAndDepth(LVal.getLValueCallIndex());
if (!Frame) {
Info.FFDiag(E, diag::note_constexpr_lifetime_ended, 1)
<< AK << LVal.Base.is<const ValueDecl*>();
@@ -3326,7 +3339,7 @@ static CompleteObject findCompleteObject(EvalInfo &Info, const Expr *E,
// to be read here (but take care with 'mutable' fields).
if ((Frame && Info.getLangOpts().CPlusPlus14 &&
Info.EvalStatus.HasSideEffects) ||
- (AK != AK_Read && Info.IsSpeculativelyEvaluating))
+ (AK != AK_Read && Depth < Info.SpeculativeEvaluationDepth))
return CompleteObject();
return CompleteObject(BaseVal, BaseType, LifetimeStartedInEvaluation);
@@ -3366,12 +3379,27 @@ static bool handleLValueToRValueConversion(EvalInfo &Info, const Expr *Conv,
CompleteObject LitObj(&Lit, Base->getType(), false);
return extractSubobject(Info, Conv, LitObj, LVal.Designator, RVal);
} else if (isa<StringLiteral>(Base) || isa<PredefinedExpr>(Base)) {
- // We represent a string literal array as an lvalue pointing at the
- // corresponding expression, rather than building an array of chars.
- // FIXME: Support ObjCEncodeExpr, MakeStringConstant
- APValue Str(Base, CharUnits::Zero(), APValue::NoLValuePath(), 0);
- CompleteObject StrObj(&Str, Base->getType(), false);
- return extractSubobject(Info, Conv, StrObj, LVal.Designator, RVal);
+ // Special-case character extraction so we don't have to construct an
+ // APValue for the whole string.
+ assert(LVal.Designator.Entries.size() <= 1 &&
+ "Can only read characters from string literals");
+ if (LVal.Designator.Entries.empty()) {
+ // Fail for now for LValue to RValue conversion of an array.
+ // (This shouldn't show up in C/C++, but it could be triggered by a
+ // weird EvaluateAsRValue call from a tool.)
+ Info.FFDiag(Conv);
+ return false;
+ }
+ if (LVal.Designator.isOnePastTheEnd()) {
+ if (Info.getLangOpts().CPlusPlus11)
+ Info.FFDiag(Conv, diag::note_constexpr_access_past_end) << AK_Read;
+ else
+ Info.FFDiag(Conv);
+ return false;
+ }
+ uint64_t CharIndex = LVal.Designator.Entries[0].ArrayIndex;
+ RVal = APValue(extractStringLiteralCharacter(Info, Base, CharIndex));
+ return true;
}
}
@@ -3497,9 +3525,6 @@ struct CompoundAssignSubobjectHandler {
LVal.moveInto(Subobj);
return true;
}
- bool foundString(APValue &Subobj, QualType SubobjType, uint64_t Character) {
- llvm_unreachable("shouldn't encounter string elements here");
- }
};
} // end anonymous namespace
@@ -3648,9 +3673,6 @@ struct IncDecSubobjectHandler {
LVal.moveInto(Subobj);
return true;
}
- bool foundString(APValue &Subobj, QualType SubobjType, uint64_t Character) {
- llvm_unreachable("shouldn't encounter string elements here");
- }
};
} // end anonymous namespace
@@ -5783,6 +5805,8 @@ public:
bool VisitObjCStringLiteral(const ObjCStringLiteral *E)
{ return Success(E); }
bool VisitObjCBoxedExpr(const ObjCBoxedExpr *E) {
+ if (E->isExpressibleAsConstantInitializer())
+ return Success(E);
if (Info.noteFailure())
EvaluateIgnoredValue(Info, E->getSubExpr());
return Error(E);
@@ -7130,8 +7154,7 @@ namespace {
: ExprEvaluatorBaseTy(Info), This(This), Result(Result) {}
bool Success(const APValue &V, const Expr *E) {
- assert((V.isArray() || V.isLValue()) &&
- "expected array or string literal");
+ assert(V.isArray() && "expected array");
Result = V;
return true;
}
@@ -7162,6 +7185,10 @@ namespace {
bool VisitCXXConstructExpr(const CXXConstructExpr *E,
const LValue &Subobject,
APValue *Value, QualType Type);
+ bool VisitStringLiteral(const StringLiteral *E) {
+ expandStringLiteral(Info, E, Result);
+ return true;
+ }
};
} // end anonymous namespace
@@ -7194,14 +7221,8 @@ bool ArrayExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
// C++11 [dcl.init.string]p1: A char array [...] can be initialized by [...]
// an appropriately-typed string literal enclosed in braces.
- if (E->isStringLiteralInit()) {
- LValue LV;
- if (!EvaluateLValue(E->getInit(0), LV, Info))
- return false;
- APValue Val;
- LV.moveInto(Val);
- return Success(Val, E);
- }
+ if (E->isStringLiteralInit())
+ return Visit(E->getInit(0));
bool Success = true;
@@ -7490,53 +7511,27 @@ class FixedPointExprEvaluator
FixedPointExprEvaluator(EvalInfo &info, APValue &result)
: ExprEvaluatorBaseTy(info), Result(result) {}
- bool Success(const llvm::APSInt &SI, const Expr *E, APValue &Result) {
- assert(E->getType()->isFixedPointType() && "Invalid evaluation result.");
- assert(SI.isSigned() == E->getType()->isSignedFixedPointType() &&
- "Invalid evaluation result.");
- assert(SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&
- "Invalid evaluation result.");
- Result = APValue(SI);
- return true;
- }
- bool Success(const llvm::APSInt &SI, const Expr *E) {
- return Success(SI, E, Result);
- }
-
- bool Success(const llvm::APInt &I, const Expr *E, APValue &Result) {
- assert(E->getType()->isFixedPointType() && "Invalid evaluation result.");
- assert(I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&
- "Invalid evaluation result.");
- Result = APValue(APSInt(I));
- Result.getInt().setIsUnsigned(E->getType()->isUnsignedFixedPointType());
- return true;
- }
bool Success(const llvm::APInt &I, const Expr *E) {
- return Success(I, E, Result);
+ return Success(
+ APFixedPoint(I, Info.Ctx.getFixedPointSemantics(E->getType())), E);
}
- bool Success(uint64_t Value, const Expr *E, APValue &Result) {
- assert(E->getType()->isFixedPointType() && "Invalid evaluation result.");
- Result = APValue(Info.Ctx.MakeIntValue(Value, E->getType()));
- return true;
- }
bool Success(uint64_t Value, const Expr *E) {
- return Success(Value, E, Result);
- }
-
- bool Success(CharUnits Size, const Expr *E) {
- return Success(Size.getQuantity(), E);
+ return Success(
+ APFixedPoint(Value, Info.Ctx.getFixedPointSemantics(E->getType())), E);
}
bool Success(const APValue &V, const Expr *E) {
- if (V.isLValue() || V.isAddrLabelDiff()) {
- Result = V;
- return true;
- }
- return Success(V.getInt(), E);
+ return Success(V.getFixedPoint(), E);
}
- bool ZeroInitialization(const Expr *E) { return Success(0, E); }
+ bool Success(const APFixedPoint &V, const Expr *E) {
+ assert(E->getType()->isFixedPointType() && "Invalid evaluation result.");
+ assert(V.getWidth() == Info.Ctx.getIntWidth(E->getType()) &&
+ "Invalid evaluation result.");
+ Result = APValue(V);
+ return true;
+ }
//===--------------------------------------------------------------------===//
// Visitor Methods
@@ -7546,7 +7541,9 @@ class FixedPointExprEvaluator
return Success(E->getValue(), E);
}
+ bool VisitCastExpr(const CastExpr *E);
bool VisitUnaryOperator(const UnaryOperator *E);
+ bool VisitBinaryOperator(const BinaryOperator *E);
};
} // end anonymous namespace
@@ -7578,6 +7575,36 @@ static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info) {
return true;
}
+static bool EvaluateFixedPoint(const Expr *E, APFixedPoint &Result,
+ EvalInfo &Info) {
+ if (E->getType()->isFixedPointType()) {
+ APValue Val;
+ if (!FixedPointExprEvaluator(Info, Val).Visit(E))
+ return false;
+ if (!Val.isFixedPoint())
+ return false;
+
+ Result = Val.getFixedPoint();
+ return true;
+ }
+ return false;
+}
+
+static bool EvaluateFixedPointOrInteger(const Expr *E, APFixedPoint &Result,
+ EvalInfo &Info) {
+ if (E->getType()->isIntegerType()) {
+ auto FXSema = Info.Ctx.getFixedPointSemantics(E->getType());
+ APSInt Val;
+ if (!EvaluateInteger(E, Val, Info))
+ return false;
+ Result = APFixedPoint(Val, FXSema);
+ return true;
+ } else if (E->getType()->isFixedPointType()) {
+ return EvaluateFixedPoint(E, Result, Info);
+ }
+ return false;
+}
+
/// Check whether the given declaration can be directly converted to an integral
/// rvalue. If not, no diagnostic is produced; there are other things we can
/// try.
@@ -7783,19 +7810,37 @@ EvaluateBuiltinClassifyType(const CallExpr *E, const LangOptions &LangOpts) {
}
/// EvaluateBuiltinConstantPForLValue - Determine the result of
-/// __builtin_constant_p when applied to the given lvalue.
+/// __builtin_constant_p when applied to the given pointer.
///
-/// An lvalue is only "constant" if it is a pointer or reference to the first
-/// character of a string literal.
-template<typename LValue>
-static bool EvaluateBuiltinConstantPForLValue(const LValue &LV) {
- const Expr *E = LV.getLValueBase().template dyn_cast<const Expr*>();
- return E && isa<StringLiteral>(E) && LV.getLValueOffset().isZero();
+/// A pointer is only "constant" if it is null (or a pointer cast to integer)
+/// or it points to the first character of a string literal.
+static bool EvaluateBuiltinConstantPForLValue(const APValue &LV) {
+ APValue::LValueBase Base = LV.getLValueBase();
+ if (Base.isNull()) {
+ // A null base is acceptable.
+ return true;
+ } else if (const Expr *E = Base.dyn_cast<const Expr *>()) {
+ if (!isa<StringLiteral>(E))
+ return false;
+ return LV.getLValueOffset().isZero();
+ } else {
+ // Any other base is not constant enough for GCC.
+ return false;
+ }
}
/// EvaluateBuiltinConstantP - Evaluate __builtin_constant_p as similarly to
/// GCC as we can manage.
-static bool EvaluateBuiltinConstantP(ASTContext &Ctx, const Expr *Arg) {
+static bool EvaluateBuiltinConstantP(EvalInfo &Info, const Expr *Arg) {
+ // This evaluation is not permitted to have side-effects, so evaluate it in
+ // a speculative evaluation context.
+ SpeculativeEvaluationRAII SpeculativeEval(Info);
+
+ // Constant-folding is always enabled for the operand of __builtin_constant_p
+ // (even when the enclosing evaluation context otherwise requires a strict
+ // language-specific constant expression).
+ FoldConstant Fold(Info, true);
+
QualType ArgType = Arg->getType();
// __builtin_constant_p always has one operand. The rules which gcc follows
@@ -7803,34 +7848,30 @@ static bool EvaluateBuiltinConstantP(ASTContext &Ctx, const Expr *Arg) {
//
// - If the operand is of integral, floating, complex or enumeration type,
// and can be folded to a known value of that type, it returns 1.
- // - If the operand and can be folded to a pointer to the first character
- // of a string literal (or such a pointer cast to an integral type), it
- // returns 1.
+ // - If the operand can be folded to a pointer to the first character
+ // of a string literal (or such a pointer cast to an integral type)
+ // or to a null pointer or an integer cast to a pointer, it returns 1.
//
// Otherwise, it returns 0.
//
// FIXME: GCC also intends to return 1 for literals of aggregate types, but
- // its support for this does not currently work.
- if (ArgType->isIntegralOrEnumerationType()) {
- Expr::EvalResult Result;
- if (!Arg->EvaluateAsRValue(Result, Ctx) || Result.HasSideEffects)
+ // its support for this did not work prior to GCC 9 and is not yet well
+ // understood.
+ if (ArgType->isIntegralOrEnumerationType() || ArgType->isFloatingType() ||
+ ArgType->isAnyComplexType() || ArgType->isPointerType() ||
+ ArgType->isNullPtrType()) {
+ APValue V;
+ if (!::EvaluateAsRValue(Info, Arg, V)) {
+ Fold.keepDiagnostics();
return false;
+ }
- APValue &V = Result.Val;
- if (V.getKind() == APValue::Int)
- return true;
+ // For a pointer (possibly cast to integer), there are special rules.
if (V.getKind() == APValue::LValue)
return EvaluateBuiltinConstantPForLValue(V);
- } else if (ArgType->isFloatingType() || ArgType->isAnyComplexType()) {
- return Arg->isEvaluatable(Ctx);
- } else if (ArgType->isPointerType() || Arg->isGLValue()) {
- LValue LV;
- Expr::EvalStatus Status;
- EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantFold);
- if ((Arg->isGLValue() ? EvaluateLValue(Arg, LV, Info)
- : EvaluatePointer(Arg, LV, Info)) &&
- !Status.HasSideEffects)
- return EvaluateBuiltinConstantPForLValue(LV);
+
+ // Otherwise, any constant value is good enough.
+ return V.getKind() != APValue::Uninitialized;
}
// Anything else isn't considered to be sufficiently constant.
@@ -8164,6 +8205,7 @@ bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
default:
return ExprEvaluatorBaseTy::VisitCallExpr(E);
+ case Builtin::BI__builtin_dynamic_object_size:
case Builtin::BI__builtin_object_size: {
// The type was checked when we built the expression.
unsigned Type =
@@ -8239,20 +8281,22 @@ bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
}
case Builtin::BI__builtin_constant_p: {
- auto Arg = E->getArg(0);
- if (EvaluateBuiltinConstantP(Info.Ctx, Arg))
+ const Expr *Arg = E->getArg(0);
+ if (EvaluateBuiltinConstantP(Info, Arg))
return Success(true, E);
- auto ArgTy = Arg->IgnoreImplicit()->getType();
- if (!Info.InConstantContext && !Arg->HasSideEffects(Info.Ctx) &&
- !ArgTy->isAggregateType() && !ArgTy->isPointerType()) {
- // We can delay calculation of __builtin_constant_p until after
- // inlining. Note: This diagnostic won't be shown to the user.
- Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
- return false;
+ if (Info.InConstantContext || Arg->HasSideEffects(Info.Ctx)) {
+ // Outside a constant context, eagerly evaluate to false in the presence
+ // of side-effects in order to avoid -Wunsequenced false-positives in
+ // a branch on __builtin_constant_p(expr).
+ return Success(false, E);
}
- return Success(false, E);
+ Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
+ return false;
}
+ case Builtin::BI__builtin_is_constant_evaluated:
+ return Success(Info.InConstantContext, E);
+
case Builtin::BI__builtin_ctz:
case Builtin::BI__builtin_ctzl:
case Builtin::BI__builtin_ctzll:
@@ -8411,6 +8455,7 @@ bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
case Builtin::BIstrncmp:
case Builtin::BIwcsncmp:
case Builtin::BImemcmp:
+ case Builtin::BIbcmp:
case Builtin::BIwmemcmp:
// A call to strlen is not a constant expression.
if (Info.getLangOpts().CPlusPlus11)
@@ -8425,6 +8470,7 @@ bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
case Builtin::BI__builtin_strncmp:
case Builtin::BI__builtin_wcsncmp:
case Builtin::BI__builtin_memcmp:
+ case Builtin::BI__builtin_bcmp:
case Builtin::BI__builtin_wmemcmp: {
LValue String1, String2;
if (!EvaluatePointer(E->getArg(0), String1, Info) ||
@@ -8455,7 +8501,9 @@ bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
QualType CharTy2 = String2.Designator.getType(Info.Ctx);
bool IsRawByte = BuiltinOp == Builtin::BImemcmp ||
- BuiltinOp == Builtin::BI__builtin_memcmp;
+ BuiltinOp == Builtin::BIbcmp ||
+ BuiltinOp == Builtin::BI__builtin_memcmp ||
+ BuiltinOp == Builtin::BI__builtin_bcmp;
assert(IsRawByte ||
(Info.Ctx.hasSameUnqualifiedType(
@@ -8523,10 +8571,12 @@ bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
return Success(0, E);
}
- bool StopAtNull = (BuiltinOp != Builtin::BImemcmp &&
- BuiltinOp != Builtin::BIwmemcmp &&
- BuiltinOp != Builtin::BI__builtin_memcmp &&
- BuiltinOp != Builtin::BI__builtin_wmemcmp);
+ bool StopAtNull =
+ (BuiltinOp != Builtin::BImemcmp && BuiltinOp != Builtin::BIbcmp &&
+ BuiltinOp != Builtin::BIwmemcmp &&
+ BuiltinOp != Builtin::BI__builtin_memcmp &&
+ BuiltinOp != Builtin::BI__builtin_bcmp &&
+ BuiltinOp != Builtin::BI__builtin_wmemcmp);
bool IsWide = BuiltinOp == Builtin::BIwcscmp ||
BuiltinOp == Builtin::BIwcsncmp ||
BuiltinOp == Builtin::BIwmemcmp ||
@@ -9123,6 +9173,22 @@ EvaluateComparisonBinaryOperator(EvalInfo &Info, const BinaryOperator *E,
return Success(CCR::Equal, E);
}
+ if (LHSTy->isFixedPointType() || RHSTy->isFixedPointType()) {
+ APFixedPoint LHSFX(Info.Ctx.getFixedPointSemantics(LHSTy));
+ APFixedPoint RHSFX(Info.Ctx.getFixedPointSemantics(RHSTy));
+
+ bool LHSOK = EvaluateFixedPointOrInteger(E->getLHS(), LHSFX, Info);
+ if (!LHSOK && !Info.noteFailure())
+ return false;
+ if (!EvaluateFixedPointOrInteger(E->getRHS(), RHSFX, Info) || !LHSOK)
+ return false;
+ if (LHSFX < RHSFX)
+ return Success(CCR::Less, E);
+ if (LHSFX > RHSFX)
+ return Success(CCR::Greater, E);
+ return Success(CCR::Equal, E);
+ }
+
if (LHSTy->isAnyComplexType() || RHSTy->isAnyComplexType()) {
ComplexValue LHS, RHS;
bool LHSOK;
@@ -9739,6 +9805,7 @@ bool IntExprEvaluator::VisitCastExpr(const CastExpr *E) {
case CK_AddressSpaceConversion:
case CK_IntToOCLSampler:
case CK_FixedPointCast:
+ case CK_IntegralToFixedPoint:
llvm_unreachable("invalid cast kind for integral value");
case CK_BitCast:
@@ -9773,12 +9840,25 @@ bool IntExprEvaluator::VisitCastExpr(const CastExpr *E) {
return Success(IntResult, E);
}
+ case CK_FixedPointToIntegral: {
+ APFixedPoint Src(Info.Ctx.getFixedPointSemantics(SrcType));
+ if (!EvaluateFixedPoint(SubExpr, Src, Info))
+ return false;
+ bool Overflowed;
+ llvm::APSInt Result = Src.convertToInt(
+ Info.Ctx.getIntWidth(DestType),
+ DestType->isSignedIntegerOrEnumerationType(), &Overflowed);
+ if (Overflowed && !HandleOverflow(Info, E, Result, DestType))
+ return false;
+ return Success(Result, E);
+ }
+
case CK_FixedPointToBoolean: {
// Unsigned padding does not affect this.
APValue Val;
if (!Evaluate(Val, Info, SubExpr))
return false;
- return Success(Val.getInt().getBoolValue(), E);
+ return Success(Val.getFixedPoint().getBoolValue(), E);
}
case CK_IntegralCast: {
@@ -9821,13 +9901,12 @@ bool IntExprEvaluator::VisitCastExpr(const CastExpr *E) {
return true;
}
- uint64_t V;
- if (LV.isNullPointer())
- V = Info.Ctx.getTargetNullPointerValue(SrcType);
- else
- V = LV.getLValueOffset().getQuantity();
+ APSInt AsInt;
+ APValue V;
+ LV.moveInto(V);
+ if (!V.toIntegralConstant(AsInt, SrcType, Info.Ctx))
+ llvm_unreachable("Can't cast this!");
- APSInt AsInt = Info.Ctx.MakeIntValue(V, SrcType);
return Success(HandleIntToIntCast(Info, E, DestType, SrcType, AsInt), E);
}
@@ -9898,16 +9977,13 @@ bool FixedPointExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
return Visit(E->getSubExpr());
case UO_Minus: {
if (!Visit(E->getSubExpr())) return false;
- if (!Result.isInt()) return Error(E);
- const APSInt &Value = Result.getInt();
- if (Value.isSigned() && Value.isMinSignedValue() && E->canOverflow()) {
- SmallString<64> S;
- FixedPointValueToString(S, Value,
- Info.Ctx.getTypeInfo(E->getType()).Width);
- Info.CCEDiag(E, diag::note_constexpr_overflow) << S << E->getType();
- if (Info.noteUndefinedBehavior()) return false;
- }
- return Success(-Value, E);
+ if (!Result.isFixedPoint())
+ return Error(E);
+ bool Overflowed;
+ APFixedPoint Negated = Result.getFixedPoint().negate(&Overflowed);
+ if (Overflowed && !HandleOverflow(Info, E, Negated, E->getType()))
+ return false;
+ return Success(Negated, E);
}
case UO_LNot: {
bool bres;
@@ -9918,6 +9994,75 @@ bool FixedPointExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
}
}
+bool FixedPointExprEvaluator::VisitCastExpr(const CastExpr *E) {
+ const Expr *SubExpr = E->getSubExpr();
+ QualType DestType = E->getType();
+ assert(DestType->isFixedPointType() &&
+ "Expected destination type to be a fixed point type");
+ auto DestFXSema = Info.Ctx.getFixedPointSemantics(DestType);
+
+ switch (E->getCastKind()) {
+ case CK_FixedPointCast: {
+ APFixedPoint Src(Info.Ctx.getFixedPointSemantics(SubExpr->getType()));
+ if (!EvaluateFixedPoint(SubExpr, Src, Info))
+ return false;
+ bool Overflowed;
+ APFixedPoint Result = Src.convert(DestFXSema, &Overflowed);
+ if (Overflowed && !HandleOverflow(Info, E, Result, DestType))
+ return false;
+ return Success(Result, E);
+ }
+ case CK_IntegralToFixedPoint: {
+ APSInt Src;
+ if (!EvaluateInteger(SubExpr, Src, Info))
+ return false;
+
+ bool Overflowed;
+ APFixedPoint IntResult = APFixedPoint::getFromIntValue(
+ Src, Info.Ctx.getFixedPointSemantics(DestType), &Overflowed);
+
+ if (Overflowed && !HandleOverflow(Info, E, IntResult, DestType))
+ return false;
+
+ return Success(IntResult, E);
+ }
+ case CK_NoOp:
+ case CK_LValueToRValue:
+ return ExprEvaluatorBaseTy::VisitCastExpr(E);
+ default:
+ return Error(E);
+ }
+}
+
+bool FixedPointExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
+ const Expr *LHS = E->getLHS();
+ const Expr *RHS = E->getRHS();
+ FixedPointSemantics ResultFXSema =
+ Info.Ctx.getFixedPointSemantics(E->getType());
+
+ APFixedPoint LHSFX(Info.Ctx.getFixedPointSemantics(LHS->getType()));
+ if (!EvaluateFixedPointOrInteger(LHS, LHSFX, Info))
+ return false;
+ APFixedPoint RHSFX(Info.Ctx.getFixedPointSemantics(RHS->getType()));
+ if (!EvaluateFixedPointOrInteger(RHS, RHSFX, Info))
+ return false;
+
+ switch (E->getOpcode()) {
+ case BO_Add: {
+ bool AddOverflow, ConversionOverflow;
+ APFixedPoint Result = LHSFX.add(RHSFX, &AddOverflow)
+ .convert(ResultFXSema, &ConversionOverflow);
+ if ((AddOverflow || ConversionOverflow) &&
+ !HandleOverflow(Info, E, Result, E->getType()))
+ return false;
+ return Success(Result, E);
+ }
+ default:
+ return false;
+ }
+ llvm_unreachable("Should've exited before this");
+}
+
//===----------------------------------------------------------------------===//
// Float Evaluation
//===----------------------------------------------------------------------===//
@@ -10282,6 +10427,8 @@ bool ComplexExprEvaluator::VisitCastExpr(const CastExpr *E) {
case CK_IntToOCLSampler:
case CK_FixedPointCast:
case CK_FixedPointToBoolean:
+ case CK_FixedPointToIntegral:
+ case CK_IntegralToFixedPoint:
llvm_unreachable("invalid cast kind for complex value");
case CK_LValueToRValue:
@@ -10929,6 +11076,23 @@ static bool EvaluateAsInt(const Expr *E, Expr::EvalResult &ExprResult,
return true;
}
+static bool EvaluateAsFixedPoint(const Expr *E, Expr::EvalResult &ExprResult,
+ const ASTContext &Ctx,
+ Expr::SideEffectsKind AllowSideEffects,
+ EvalInfo &Info) {
+ if (!E->getType()->isFixedPointType())
+ return false;
+
+ if (!::EvaluateAsRValue(E, ExprResult, Ctx, Info))
+ return false;
+
+ if (!ExprResult.Val.isFixedPoint() ||
+ hasUnacceptableSideEffect(ExprResult, AllowSideEffects))
+ return false;
+
+ return true;
+}
+
/// EvaluateAsRValue - 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
@@ -10954,6 +11118,12 @@ bool Expr::EvaluateAsInt(EvalResult &Result, const ASTContext &Ctx,
return ::EvaluateAsInt(this, Result, Ctx, AllowSideEffects, Info);
}
+bool Expr::EvaluateAsFixedPoint(EvalResult &Result, const ASTContext &Ctx,
+ SideEffectsKind AllowSideEffects) const {
+ EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects);
+ return ::EvaluateAsFixedPoint(this, Result, Ctx, AllowSideEffects, Info);
+}
+
bool Expr::EvaluateAsFloat(APFloat &Result, const ASTContext &Ctx,
SideEffectsKind AllowSideEffects) const {
if (!getType()->isRealFloatingType())
@@ -10986,6 +11156,8 @@ bool Expr::EvaluateAsConstantExpr(EvalResult &Result, ConstExprUsage Usage,
const ASTContext &Ctx) const {
EvalInfo::EvaluationMode EM = EvalInfo::EM_ConstantExpression;
EvalInfo Info(Ctx, Result, EM);
+ Info.InConstantContext = true;
+
if (!::Evaluate(Result.Val, Info, this))
return false;
@@ -11626,6 +11798,7 @@ bool Expr::EvaluateWithSubstitution(APValue &Value, ASTContext &Ctx,
const Expr *This) const {
Expr::EvalStatus Status;
EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpressionUnevaluated);
+ Info.InConstantContext = true;
LValue ThisVal;
const LValue *ThisPtr = nullptr;
@@ -11709,6 +11882,7 @@ bool Expr::isPotentialConstantExprUnevaluated(Expr *E,
EvalInfo Info(FD->getASTContext(), Status,
EvalInfo::EM_PotentialConstantExpressionUnevaluated);
+ Info.InConstantContext = true;
// Fabricate a call stack frame to give the arguments a plausible cover story.
ArrayRef<const Expr*> Args;
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-10 19:04:03 +0000