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 ?

What is packet switching? explain, Question 1 What are the five subscriber...

Question 1 What are the five subscriber-related signaling functions performed by the operator? Question 2 Compare Microprogrammed control and Hard-wired control Que

What features should the hospital software contain?, What Features Should t...

What Features Should the Software Contain? Although the needs of every nursing department, hospital, pharmacy, would vary, certain common features are desirable in the software

Challenges in building information system, discuss the three major challeng...

discuss the three major challenges in building information system in an organization

HOMEWORK 9.., AsBased on Chapter Review Problems from the book. 1 #1. Wh...

AsBased on Chapter Review Problems from the book. 1 #1. What is meant by data independence? Explain your answer. #2. Identify two benefits of separating application software fr

Discuss the advantages and disadvantages of printed indexes, QUESTION 1 ...

QUESTION 1 Discuss the advantages and disadvantages of printed indexes. QUESTION 2 (i) The Library of Congress Subject Headings List and the Sears Subject Headings List

What technical challenges must be overcome, QUESTION a) Clearly explain...

QUESTION a) Clearly explain three main issues arising in the design of components for use in Intranets. b) Explain the term "location-aware Computing". c) The Internet en

Types of computer on basis of size and capabilities, Another way of classif...

Another way of classifying a computer system is based upon its size and capabilities: Microcomputers: Microcomputers are systems based on the use of microprocessors. A Micr

What are the most common forms of mixing, Question 1 What is the differenc...

Question 1 What is the difference between Variable Bit Rate and Constant Bit Rate? Question 2 Write a note on: Normalization, Reverberation, Noise Reduction, Filters, and

Internet, how to get tamil information in internet

how to get tamil information in internet

Time sharing system , Time Sharing System: With the use multiprogrammi...

Time Sharing System: With the use multiprogramming, the batch processing can be quite  efficient. However, for many jobs, it is desirable to provide a mode in which the user i

Write Your Message!

Captcha
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!

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