More Jumps

Notes

• This is Jorgensen chapter 7.7
• jmp is an unconditional jump.
• Last time we looked at a set of conditional jump instructions.
• Assemblers add more then these basic jumps.
• But first cmp
  • cmp op1, op2
  • Op1 and op2 must be the same size
  • op2 can not be an immediate
  • Both can not be memory
  • The operands are not changed
  • But the appropriate bits in the flag register are set.
• The assembler then can use any conditional branching instruction
• They depend on the type of numbers compared.
• je, jne
  • Work for signed and unsigned data.
  • Jump equal, jump not equal
• For signed numbers
  • jl, jle (jump less, jump less equal)
  • jg, jge (jump greater, jump greater equal)
• For unsigned numbers
  • jb, jbe (jump below, jump below equal)
  • ja, jae (jump above, jump above equal)
• The jumps from last time too.
• They are summarized on the cheat sheet.