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 ?

Data input , Data Input : There are several aspects of data input that nee...

Data Input : There are several aspects of data input that need careful consideration. We shall assume that in a laboratory environment you are mainly concerned with entering data

Software engineering, assignment 1:architectural design 2: component des...

assignment 1:architectural design 2: component design

Explain any five different types of computers, Question 1 Explain any five...

Question 1 Explain any five different types of computers Question 2 Describe Bus Type LAN. Its disadvantages and advantages and examples Question 3 Describe the

#title., what is input and output device? explain meaning of input and outp...

what is input and output device? explain meaning of input and output devices

Flowcharts, flowchart that display yhe students average scores for 3 quizze...

flowchart that display yhe students average scores for 3 quizzes.Assume that there are 3 sections having 5 student each.Valid number is 1-100 for the quizzes.Enter an invalid numbe

Function, function of arithmetic logic unit

function of arithmetic logic unit

Explain the types of memory and explain how each work, Problem: a) ...

Problem: a) Explain the basic functions of a computer: inputting, processing, storing and outputting. b) List four types of memory and explain how each wor

Advantages and disadvantages of e-learning, Advantages and Disadvantages of...

Advantages and Disadvantages of E-Learning: Before we discuss about advantages and disadvantages of e-learning, you should know that e-learning is just another model for learn

Explain the functions of alu, Question 1 Write down the Booth's Multiplica...

Question 1 Write down the Booth's Multiplication Algorithm. Justify the Booth's Multiplication Algorithm Question 2 Explain the functions of ALU Question 3 Define the term ins

Digital logic design, encoder

encoder

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