MIP 设计相关

• 准备: index (uproct); odt, bom, sym-tbl, omt; design
  • pre: doc, src
  • 用啥的语言实现?
  • 因为各个组件之间存在依赖关系, 如 instruction stream 依赖 ODV, OES, 所以还是要先把每一样弄清, 再 design
  • bom: 这个要分析的, 不知道这个, 就不知道用户程序里的所有 BRK statement, 而这些断点也含 MI 程序自己指定的!
  • 输出问题: rpg 里向 splf 输出挺方便的, 可以考虑支持 splf 输出

ODV

An ODV entry is required for each object described in the ODT. The index value for a particular object ODV entry is used as an operand for instructions that operate on the object. An ODT can contain 8,191 entries in template version 0 and 65,526 entries in template version 1. The first entry has an index value of 1.

Remarks:

这里需要注意的是 ODT 序号由 1 开始

Each ODV entry generally consists of the following:

• Type information
  • The first 2 bytes of each ODV entry contain information identifying the type and general attributes of the object.
• OES offset or attribute information
  • The last 2 bytes of each ODV entry contain either detailed attribute information or an offset into the OES where the detailed attribute information is found.

    Remarks:

    注意, ODV里到 OES component 当中的 offset 是 2-byte 的

    由下面的说明中, 可以看出, ODV entry 中到 OES 的 offset, 是从 OES component 开头开始的; 这同时说明, OES component 的大小不会超过 64K

    The OES contains a 4-byte OES length entry at the beginning of the OES component. This means that the minimum valid offset is 4 bytes.

    Remarks:

    OES component 开头 4-byte 是整个 OES 的长度

OES

The OES consists of a series of variable-length entries that complete an object's description. Several ODV entries for different objects with identical definitions can share the same OES entry. Each OES entry consists of the following:

• OES header. One byte indicating which OES appendages are present. A bit is included for each possible OES appendage. A binary 0 value for the bit means the appendage is not present. A binary 1 value for the bit means the appendage is present.

  Remarks:

  oes header 是 1-byte, 每位表示一个 appendage

Scalar Data Object