**Lecture 01: Computer Systems**
Anthony J. Clark
# First
- Survey
- Administrivia
# About the course
- Linux heavy (ask about Windows and I'll try my best)
+ Student side project
+ Historical cruft
+ BSD / Unix / Linux
- Hardware (first) and Operating Systems (second)
# Drawing
**von Neumann machine**
- Drawing: Program running on your computer
+ CPU (registers, ALU, status)
+ Memory buss
* Stack (down from `0x00007fffffffffff`)
* heap (up)
* bss
* data
* code (`0x0000000000000000`)
- CPU Lies
+ pipelining
+ branch prediction
+ speculative execution
+ hyperthreads
+ data flow analysis
+ instruction level parallelism
# Programs and Memory
~~~c
long myfunc(long a, long b, long c, long d,
long e, long f, long g, long h)
{
long xx = a * b * c * d * e * f * g * h;
long yy = a + b + c + d + e + f + g + h;
long zz = utilfunc(xx, yy, xx % yy);
return zz + 20;
}
~~~
- Locals and Globals
- Pointers / References
+ arithmetic
- [Compiler Explorer](https://godbolt.org/)
# Server Use
- Demo server access (might wait until practice day)
# Resources
- [Where the top of the stack is on x86 - Eli Bendersky's website](https://eli.thegreenplace.net/2011/02/04/where-the-top-of-the-stack-is-on-x86/)
- [The Memory Layout of a 64-bit Linux Process](https://simonis.github.io/Memory/)