{ FS_OPT_SUB_SUB_X_Y_Z, "algebraic simplification: (x - y) - z = x - (y + z)" },
{ FS_OPT_SUB_C_NOT_X, "algebraic simplification: c - ~a = a + (c+1)" },
{ FS_OPT_SUB_TO_ADD, "algebraic simplification: (-a) - b = -(a + b), a - (b - c) = a + (c - b), a - (b * C) = a + (b * -C)" },
{ FS_OPT_SUB_SUB_X_Y_Z, "algebraic simplification: (x - y) - z = x - (y + z)" },
{ FS_OPT_SUB_C_NOT_X, "algebraic simplification: c - ~a = a + (c+1)" },
{ FS_OPT_SUB_TO_ADD, "algebraic simplification: (-a) - b = -(a + b), a - (b - c) = a + (c - b), a - (b * C) = a + (b * -C)" },