5 Matching Annotations
  1. Mar 2022
    1. ○ This changes the format and structure of the code but preserves the semantics (what it does)○ Can change lots of details for optimization, as long as the overall effect is the same

      compiler 部分的流程是什么?

  2. Nov 2021
    1. The most general form is shown at the bottomof the table with syntax Imm(rb,ri,s). Such a reference has four components: animmediate offset Imm, a base register rb, an index register ri, and a scale factors, where s must be 1, 2, 4, or 8. Both the base and index must be 64-bit registers.The effective address is computed as Imm + R[rb] + R[ri] . s.

      访问 $$Imm(r_b, r_i, s)$$ 的内存应该如何计算,有哪些限制条件?

    2. C declaration Intel data type Assembly-code suffix Size (bytes)

      不同数据类型的 size 以及在 assembly 中的后缀?

    3. A final difference is that we see two additional lines of code (lines8–9). These instructions will have no effect on the program, since they occur afterthe return instruction (line 7). They have been inserted to grow the code for thefunction to 16 bytes, enabling a better placement of the next block of code in termsof memory system performance.

      为什么有时候通过 disassembly 生成的 assembly 代码会在 ret 之后通过 nop 增加一些空格?

    4. Its main feature isthat it is in a more readable textual format, as compared to the binary format ofmachine code.

      assembly code 和 machine code 相比最大的区别是什么?