if (classLikeDeclaration is FirRegularClass) {
            if (calleeReference is FirResolvedNamedReference) {
                val callee = calleeReference.resolvedSymbol.fir as? FirCallableDeclaration
                // TODO: check callee owner directly?
                if (callee !is FirConstructor && callee?.isStatic != true) {
                    classLikeDeclaration.companionObjectSymbol?.let { return it.fir.buildSymbol(symbolBuilder) }

 *
 * in which the `f` in 2) is regarded as used and `f` in 1) is not.
 */
private fun doesCallExpressionUseCallee(callee: PsiElement): Boolean {
    return callee !is KtReferenceExpression ||
            analyze(callee) {
                isSimpleVariableAccessCall(callee)
            }
}

/**
 * The body of setters are always used. The body of getters are only used if they are expression bodies.
 */

        val firCall = ktCallElement.getOrBuildFir(firResolveSession)?.unwrapSafeCall() as? FirCall ?: return null

        val callee = (firCall.toReference(firResolveSession.useSiteFirSession) as? FirResolvedNamedReference)?.resolvedSymbol
        if (callee?.fir?.origin == FirDeclarationOrigin.SamConstructor) {
            val substitutor = (firCall as? FirQualifiedAccessExpression)