diff --git a/clang/include/clang/Basic/Builtins.td b/clang/include/clang/Basic/Builtins.td index bda8a48be92bd..e1b4d5b1fdc0a 100644 --- a/clang/include/clang/Basic/Builtins.td +++ b/clang/include/clang/Basic/Builtins.td @@ -2714,6 +2714,7 @@ def Abs : IntMathTemplate, LibBuiltin<"stdlib.h"> { let Attributes = [NoThrow, Const]; let Prototype = "T(T)"; let AddBuiltinPrefixedAlias = 1; + let OnlyBuiltinPrefixedAliasIsConstexpr = 1; } def Calloc : LibBuiltin<"stdlib.h"> { diff --git a/clang/lib/AST/ByteCode/InterpBuiltin.cpp b/clang/lib/AST/ByteCode/InterpBuiltin.cpp index 65c7b4e5306d7..8a27658d7fb6a 100644 --- a/clang/lib/AST/ByteCode/InterpBuiltin.cpp +++ b/clang/lib/AST/ByteCode/InterpBuiltin.cpp @@ -563,6 +563,17 @@ static bool interp__builtin_fabs(InterpState &S, CodePtr OpPC, return true; } +static bool interp__builtin_abs(InterpState &S, CodePtr OpPC, + const InterpFrame *Frame, const Function *Func, + const CallExpr *Call) { + PrimType ArgT = *S.getContext().classify(Call->getArg(0)->getType()); + APSInt Val = peekToAPSInt(S.Stk, ArgT); + if (Val.isNegative()) + Val.negate(); + pushInteger(S, Val, Call->getType()); + return true; +} + static bool interp__builtin_popcount(InterpState &S, CodePtr OpPC, const InterpFrame *Frame, const Function *Func, @@ -1808,6 +1819,13 @@ bool InterpretBuiltin(InterpState &S, CodePtr OpPC, const Function *F, return false; break; + case Builtin::BI__builtin_abs: + case Builtin::BI__builtin_labs: + case Builtin::BI__builtin_llabs: + if (!interp__builtin_abs(S, OpPC, Frame, F, Call)) + return false; + break; + case Builtin::BI__builtin_popcount: case Builtin::BI__builtin_popcountl: case Builtin::BI__builtin_popcountll: diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp index 52a7f5778ce6d..d1d6790e15252 100644 --- a/clang/lib/AST/ExprConstant.cpp +++ b/clang/lib/AST/ExprConstant.cpp @@ -13055,6 +13055,19 @@ bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E, return Success(Val.popcount() % 2, E); } + case Builtin::BI__builtin_abs: + case Builtin::BI__builtin_labs: + case Builtin::BI__builtin_llabs: { + APSInt Val; + if (!EvaluateInteger(E->getArg(0), Val, Info)) + return false; + if (Val == APSInt(APSInt::getSignedMinValue(Val.getBitWidth()), false)) + return false; + if (Val.isNegative()) + Val.negate(); + return Success(Val, E); + } + case Builtin::BI__builtin_popcount: case Builtin::BI__builtin_popcountl: case Builtin::BI__builtin_popcountll: diff --git a/clang/test/AST/ByteCode/builtin-functions.cpp b/clang/test/AST/ByteCode/builtin-functions.cpp index 450ff5671314d..46e5b0579bd57 100644 --- a/clang/test/AST/ByteCode/builtin-functions.cpp +++ b/clang/test/AST/ByteCode/builtin-functions.cpp @@ -265,6 +265,15 @@ namespace fpclassify { char classify_subnorm [__builtin_fpclassify(-1, -1, -1, +1, -1, 1.0e-38f)]; } +namespace abs { +static_assert(__builtin_abs(14) == 14, ""); +static_assert(__builtin_labs(14L) == 14L, ""); +static_assert(__builtin_llabs(14LL) == 14LL, ""); +static_assert(__builtin_abs(-14) == 14, ""); +static_assert(__builtin_labs(-14L) == 14L, ""); +static_assert(__builtin_llabs(-14LL) == 14LL, ""); +} // namespace abs + namespace fabs { static_assert(__builtin_fabs(-14.0) == 14.0, ""); }