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 ?

COMPUTERS IN EDUCATION, What is CAI?Explain its pitsfalls

What is CAI?Explain its pitsfalls

C language, parent and child process using c language

parent and child process using c language

Arrays and strings, This is a C file. 1. The program starts by printing you...

This is a C file. 1. The program starts by printing your name with an end sign ">". For example, "NAME >"; 2. Then, you can type in a string. If the string is not "vi xxx", you pri

How to find percentage in c++, I have written all formulas fine but still i...

I have written all formulas fine but still its showing 0 as percentage please help me in this program user have to enter obtain score and total score

Expert system, Develop a simple expert system to pick ten stocks to conside...

Develop a simple expert system to pick ten stocks to consider. Create seven or more rules that could be used in such an expert system. Create five cases and use the rules

Problem solving using a computer, PROBLEM SOLVING USING A COMPUTER The ...

PROBLEM SOLVING USING A COMPUTER The following steps are required for solving a problem using a computer system: Problem Definition Program Planning (Preparati

String problem, c program to convert S to palindromes with minimum number o...

c program to convert S to palindromes with minimum number of character replacements

Embedded system, what question can be asked for embedded system

what question can be asked for embedded system

How to avoid race conditions with critical section?, • The key to preventi...

• The key to preventing problem involving shared storage is get some way to prohibit more than one process from reading and writing the shared data concurrently. That part of the p

Fourth generation of computers, THE FOURTH GENERATION (1975 ONWARDS) ...

THE FOURTH GENERATION (1975 ONWARDS) This generation of computers have one or more of the following characteristics: Semi-conductor memory instead of core memo

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