Method PopSignedQWord

src/newgrf_text.cpp:722–722

		return val | (((uint64_t)this->PopUnsignedDWord()) << 32);
	}
	int64_t  PopSignedQWord()   { return (int64_t)this->PopUnsignedQWord(); }

	/** Rotate the top four words down: W1, W2, W3, W4 -> W4, W1, W2, W3 */
	void RotateTop4Words()