Chapter 3.5, Problem 3.8PP

Program Plan Intro

Unary and Binary Operations:

• The details of unary operations includes:
  • The single operand serves as both source as well as destination.
  • It can either be a register or a memory location.
  • The instruction “incq” causes 8 byte element on stack top to be incremented.
  • The instruction “decq” causes 8 byte element on stack top to be decremented.
• The details of binary operations includes:
  • The first operand denotes the source.
  • The second operand serves as both source as well as destination.
  • The first operands can whichever be an immediate value, memory location or register.
  • The second operands can whichever be a register or a memory location.

Example:

The example for a “subq” instruction is shown below:

subq %rax, %rdx

Here, “%rax” and “%rdx” denotes registers. The given code decrements register “%rdx” by value in “%rax”.