Reread Computer System a programmer's perspective Chapter_2by luvex

A review of rereading chapter 2–Representing and Manipulating Information.

Contents of Chapter 1:

1. Information Storage
2. Integer Representations
3. Integer Arithmetic
4. Floating Point
5. Summary

Information Storage

• transfer among Binary, Decimal&Hexadecimal
• Every computer has a word size(representing virtual address 32bit/64bit)
• Big endian or Little endian (should be noticed when data are communicated over a newwork)

• swapping value > void inplace_swap(int *x, int *y) { *y = *x ^ *y; *x = *x ^ *y; *y = *x ^ *y; } //For an array with odd length, we must be careful with the middle element which could be set to 0 under such swapping

• Boolean Algebra : &

  ~ ^

• Other Operations:
  • Mask Operation

  • Logical Operation : ! &&

  • Shift Operations : « » (The difference between logical&arithmetic operations)
• In this part, it mainly talks about bit-level calculation.

Integer Representations

Integer Arithmetic

Floating Point

Summary