Example Programs

• Hello world: hello.ic, hello.s
• Fibonacci computation: fib.ic, fib.s
• Objects example: objects.ic, objects.s


Calling conventions

• Function arguments pushed on stack in reverse order
• Return value stored in %eax register (not on stack)
• Caller-saved registers: %eax, %ecx, %edx
• Callee-saved registers: %ebx, %esi, %edi, %ebp, %esp
  

Pentium Instruction Set Architecture

• A short, but good intro to x86 assmebly and stack frame layout. Uses AT&T Syntax.
• A quick description of the Pentium Instruction Set (taken from the nasm assembler documentation; uses Intel syntax)
  
• Complete documentation: Intel Manuals page, which includes:
• Intel Architecture Optimizations Manual
• Intel Architecture Software Developer's Manual, Volume 1: Basic Architecture
• Intel Architecture Software Developer's Manual, Volume 2: Instruction Set Reference Manual (A-M)
• Intel Architecture Software Developer's Manual, Volume 2: Instruction Set Reference Manual (N-Z)
• Intel Architecture Software Developer's Manual, Volume 3: System Programming Guide
  

Other Tools

• GDB, the GNU debugger
• Documentation for the as assembler: Postscript, HTML (uses the AT&T syntax)
  

AT&T versus Intel Syntax

	AT&T	Intel
Order of operands	op a,b  means  b = a op b  (second operand is destination)	op a, b   means  a = a op b (first operand is destination)
Memory addressing	disp(base, offset, scale)	[base + offset*scale + disp]
Size of memory operands	instruction suffixes (b,w,l) (e.g., movb, movw, movl)	operand prefixes (e.g., byte ptr, word ptr, dword ptr)
Registers	%eax, %ebx, etc.	eax, ebx, etc.
Constants	$4, $foo, etc	4, foo, etc

Assembling and linking commands

To assemble and link the file "file.s", use:

gcc -g -o file.exe file.s libic.a


The library file libic.a is a collection of .o files bundled together, containing the code for all of the library functions defined in the language specification, along with run-time support for garbage collection. The -g flag enables you to use gdb to step through your program.

The IC library is also available for Intel Macs running FreeBSD: libic.osx.a.