1. X86 Architecture

3. Intel’s Dilemma
All (most) software uses CISC code and needs a CISC ISA
RISC is more efficient, CISC is cumbersome
Pentium
CISC Input machine code
Translation CISC to RISC
Execution as RISC

4. Pentium Architecture
CISC
RISC

5. Pentium Pipeline

22. // Test1.cpp : Defines the entry point for the console application.
#include "stdafx.h"
int _tmain(int argc, _TCHAR* argv[]) {
int x,y,z;
x = 3;
E mov dword ptr [x],3 puts 3 into memory at address x
y = 5;
mov dword ptr [y],5 puts 5 into memory at address y
z = x + y;
C mov eax,dword ptr [x] moves data at address x into eax
F add eax,dword ptr [y] adds data at address y to eax
mov dword ptr [z],eax moves contents of eax to memory at y
return 0;
xor eax,eax }