Fix FPAccurary bug exposed by new builtin exp10

Author: jsji

clang/lib/CodeGen/CGBuiltin.cpp

@@ -2509,9 +2509,9 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
     case Builtin::BI__builtin_exp2f16:
     case Builtin::BI__builtin_exp2l:
     case Builtin::BI__builtin_exp2f128:
-      return RValue::get(emitUnaryMaybeConstrainedFPBuiltin(*this, E,
-                                   Intrinsic::exp2,
-                                   Intrinsic::experimental_constrained_exp2));
+      return RValue::get(emitUnaryMaybeConstrainedFPBuiltin(
+          *this, E, Intrinsic::exp2, Intrinsic::experimental_constrained_exp2,
+          Intrinsic::fpbuiltin_exp2));
     case Builtin::BI__builtin_exp10:
     case Builtin::BI__builtin_exp10f:
     case Builtin::BI__builtin_exp10f16: