Linker & Loader
# History
The earliest computers were programmed entirely in machine languages.
Hand assemble and punch in into cards or tapes.
if subprogram is changed , whole remaking is needed.
Assembler solved this problem .
Assembler binds the names of subprograms to addresses.
DLL :
最初のプログラムに呼ばれるまで、アドレスを割り振らず、
かつ使用するプログラムがなくなるとメモリから消える。
毎回この動的な図書を使用する際は、
アドレスを割り当てる仲介業者が存在する。Interface exists.
よって柔軟。
# Architecture
ABI (Application Binary Interface)
: "Every" Operating System presents an ABI to programs that run under that system
- System V ABI
Based addressing
:
- register : points a space of address
- operand : points a detailed address
Indexed addressing
:
- register : points a detailed address
- operand : points a space of address