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 ?

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

Syntax - programming language, Syntax: Syntax provides the structure a...

Syntax: Syntax provides the structure and how to formulate the phrase or sentence w.r.t grammar of the language. It tells us about which composition is allowed from the charac

Execution of a machine instruction, Execution of a machine instruction: ...

Execution of a machine instruction: Execution of a machine instruction on modern processors involves a complex sequence of operations with multiple cycles. One instruction cyc

Working of web browser, Working of web Browser: Internet is character...

Working of web Browser: Internet is characterized by the Client Server Computing that consists of three basic components: The Web client which may be the web browser;

Cryptography, Assume |s1|=|s2|=n and consider the functions defined, for an...

Assume |s1|=|s2|=n and consider the functions defined, for any s1 and s2, as: (a) G1(s1,s2)=s1 xor s2, (b) G2(s1,s2)=(s1, s2, s1 xor s2). We have that: A. G1 and G2 are pseudo-ra

Application-specific multiprocessors, Application-Specific Multiprocessors ...

Application-Specific Multiprocessors Although this book details a variety of similar architectures, it specializes in the design of such architectures in the perspective of par

Artificial intelligence-representations/languages used, Many persons are ta...

Many persons are taught AI with the opening line: " The three most important things in AI are representation, representation and representation ". While selecting the method of

operator, what is operator and operator associativel

what is operator and operator associatively

Assignment, Hi I have an assignment can you help me ?

Hi I have an assignment can you help me ?

Description of external hardware interruptions, External interruptions are...

External interruptions are produced by peripheral devices, for example keyboards, printers, communication cards, etc. They are also produced by coprocessors. It is not achievable t

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