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 ?

Explain se process model objective, Question 1 Explain attributes, propert...

Question 1 Explain attributes, properties, and characteristics of system Question 2 What do understand from Organizational Aspects of System Life Cycles? Explain Question

Cprgm, A palindrome is a string that reads the same from both the ends. Giv...

A palindrome is a string that reads the same from both the ends. Given a string S convert it to a palindrome by doing character replacement. Your task is to convert S to palindrome

ASSIGNMENTS, A STAIRCASE LIGHT IS CONTROLLED BY TWO SWITCHES ONE AT THE TOP...

A STAIRCASE LIGHT IS CONTROLLED BY TWO SWITCHES ONE AT THE TOP OF THE STAIRS AND ANOTHER AT THE BOTTOM OF STAIRS

Communication networks and local area networks, Communication Networks: ...

Communication Networks: Communication networks are made up of transmission lines, concentrators, switching mechanisms and non-data processing components. Due to increased comp

Cryptography, For which X,Y in {o, O, Theta, Omega, omega}, do the relation...

For which X,Y in {o, O, Theta, Omega, omega}, do the relationships t(n)+t''(n) = X(min(t(n),t''(n))) and t(n)+t''(n) = Y(max(t(n),t''(n))) hold for all t,t'' such that t(n),t''(n)

Some CPUs provide multiple modes of operation, even though most systems onl...

even though most systems only distinguish among user and kernel modes, some CPUs provide multiple modes. Multiple modes could be used to provide a finer-grained security strategy.

Base, 123 is not valid in which base value

123 is not valid in which base value

Arithmetic and control unit, micro routine

micro routine

Programming languages, difference between a compiler and a translator

difference between a compiler and a translator

Characterizations of artificial intelligence, Characterizations of Artifici...

Characterizations of Artificial Intelligence Artificial Intelligence is a typical science to describe, because it has fuzzy borders with, psychology, computer science, mathemat

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