katlyndah/csapp

Computer Systems: A Programmer's Perspective

Computer Systems: A Programmer's Perspective 3rd edition

Here you can find all of the end of chapter problems in the csapp book, as well
as some practice problems and random experiments. This is mainly for me to
keep everything in one place as I am using multiple machines, but I made it
public so potentially someone else might get something out of it.

Building the Y86-64 simulators for Chapter 4

The simulator tools and documentation can be downloaded from this page
under Chapter 4: Processor Architecture

I had to fix a few things in order to get the simulator to build. I was
running this on Raspberry Pi OS, should be similar for other linux distros:

1. Install flex
   sudo apt install flex
2. Download and build Tcl
3. Download and build Tk
   Both can be downloaded from here
4. Update the outermost Makefile in the sim directory
   • enable GUI mode by uncommenting the line:
     GUIMODE=-DHAS_GUI
   • Point the linker to the tcl and tk libraries, for me this was:
     TKLIBS=-L/usr/local/lib -ltcl8.6 -ltk8.6
   • Point the compiler to the tcl and tk header files (tcl.h and tk.h).
     Also since tcl apparently deprecated some things after version 8.5,
     in order to build projects using some deprecated code, you have to
     #define USE_INTERP_RESULT before including tcl.h. This can be done
     via a compiler flag.
     TKINC=-D USE_INTERP_RESULT -isystem /usr/include/tcl8.6

Note on buggy behavior with simulator memory

I noticed that if you allocate some memory directly in Y86-64 and try to assign
an 8 byte hex value (specifying all 8 bytes explicitly), then the simulator
doesn't work properly. The memory contents viewer and the register display both
do not show correct values.

For example creating an array like this:

    .align 8
array:
    .quad 0x0123456789ABCDEF
    .quad 0x0123456789ABCDEF
    .quad 0x0123456789ABCDEF
    .quad 0x0123456789ABCDEF

I have only had success with small values like this:

    .align 8
array:
    .quad 0xA
    .quad 0xB
    .quad 0xC
    .quad 0xD