learn,how to mix C and Assembly Language ?, Basic Computer Science

learn,how to mix C and Assembly Language ?, Basic Computer Science

Assignment Help:

The technique to mix C and assembly language is to apply the "asm" directive. To access C-language variables from assembly language, you just use the C identifier that name is a memory operand. These variables cannot be local to a procedure, and also cannot be static within a procedure. They have to be global (but can be static global). The newline characters are essential.
unsigned long a1, r;
void junk( void )
{
asm(
"pushl %eax \n"
"pushl %ebx \n"
"movl $100,%eax \n"
"movl a1,%ebx \n"
"int $59 \n"
"movl %eax,r \n"
"popl %ebx \n"
"popl %eax \n"
);
}

This instance does the following:
1. Pushes the value stored in %eax and %ebx onto the stack.
2. Puts a value of 100 into %eax.
3. Copies the value in global variable a1 into %ebx.
4. Executes a software interrupt number 59.
5. Copies the value in %eax into the global variable r.
6. Restores (pops) the contents of the temporary registers %eax and %ebx.

Related Discussions:- learn,how to mix C and Assembly Language ?

E-mail, E-MAIL: Internet has changed the art of writing letters to ema...

E-MAIL: Internet has changed the art of writing letters to email. Email is one of the ways on Internet to send messages to another person across the network. E-mail and posta

Ipv4 and ipv6, IPv6 documented in 1994 (RFC 1752) is still a collection...

IPv6 documented in 1994 (RFC 1752) is still a collection of Draft and Proposed standards Several pre-standard implementations exist IPv6 was intended to be a pragmatic up

COMPUTER SYSTEM ARCHITECTURE, PLEASE HELP ME TO CONSTRUCT THE XOR GATE USIN...

PLEASE HELP ME TO CONSTRUCT THE XOR GATE USING ONLY NAND GATE

Applications software, Applications Software: General aspects on appli...

Applications Software: General aspects on applications software. Applications software is the program that allow the user to get the required work done. In other words, applic

Enterprise resource planning, ENTERPRISE RESOURCE PLANNING What ...

ENTERPRISE RESOURCE PLANNING What has football got to do with it? asks management guru Michael Hammer in his latest best seller Beyond Reengineering. The answer is almos

Operating system, advantage and disadvantage of operating system

advantage and disadvantage of operating system

Explain any two issues in web design, Question 1 Explain any two issues in...

Question 1 Explain any two issues in web design Question 2 Mention the factors considered for good design Question 3 What are the advantages of graphical system?

Defferentiat hardware and software and gave example, defferentiat hardware ...

defferentiat hardware and software and gave example

Data base, advantages of file base system

advantages of file base system

Syntax - programming language, Syntax: Syntax provides the structure a...

Syntax: Syntax provides the structure and how to formulate the phrase or sentence w.r.t grammar of the language. It tells us about which composition is allowed from the charac

Write Your Message!

Name

Email id

Message

Verfication Code

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

Submit Assignment

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd