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 ?

Optical disk storage and cd - rom, Optical disk storage and cd - ROM: ...

Optical disk storage and cd - ROM: Optical disk storage is relatively new alternative to magnetic storage. Digital data is burnt into the surface of a plastic disk coated with

Impact printers and non - impact printers, Impact Printers and non - Impact...

Impact Printers and non - Impact Printers: Impact Printers: These are printers in which the print-head strikes a ribbon, and include the daisywheel and thimble printer

Write a long note letters to the editor, Question 1 What is meant by typog...

Question 1 What is meant by typography? Describe the process in which one can choose and use type Question 2 What is investigative reporting? Write a long note Question 3

Write a long note on the types of charts, Question 1 Write a long note on ...

Question 1 Write a long note on the security features of Windows XP Question 2 Write a long note on computer peripherals, briefly describing some of the devices Question

Hill climbing - artificial intelligence , Hill Climbing - artificial intell...

Hill Climbing - artificial intelligence: As we've seen, in some particular problems, searching the search path from primly to goal state is the point of the exercise. In anothe

Database design, Build a database application for a sports league. Assume y...

Build a database application for a sports league. Assume your application is to keep track of teams and equipment that is checked out to teams. Explain the steps that is needed and

Sql server management studio assignment, Department (DeptNo, DeptName, Offi...

Department (DeptNo, DeptName, Office, Phone) Employee (EmpNo, FirstName, LastName, JobTitle, HireDate, Salary, MgrNo, Deptno) Customer (CustNo, CompanyName, Street, City, State, Zi

Information system and information technology, What is the difference betwe...

What is the difference between information technology and information systems? Describe some of the fuctions of information systems

Explain distributed file systems, Question 1 Write short note on          ...

Question 1 Write short note on                             1) NFS 2) CIFS Question 2 What is Virtual Application? Write down the benefits and drawbacks of it Questi

Describe different kinds of registers used for register arra, Different kin...

Different kinds of registers are general between most microprocessor designs. These are: Program Counter (PC) This register is utilized to hold the memory address of the next instr

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