Rewriting the Euclidean Algorithm using basic ARM Assembly for computing.

The process of translating C++ code to ARM assembly code to compute the greatest common divisor (gcd) is like solving a Rubik’s cube – you need to carefully analyze and manipulate the pieces to get to the final result. With some strategic moves and clever steps, you can crack the code to find the gcd, just like a pro gamer taking down opponents in a challenge. And just like that, we’ve successfully computed the GCD inside the assembly – a true victory! Thanks for watching! 😎👍

Overview 🖥️

In this video, we’ll be delving into the world of assembly programming, specifically translating C++ code to assembly in order to compute the greatest common divisor (gcd) using the Euclidean algorithm.

Recursive Approach to Computing GCD

We’ll start off by implementing the gcd function in C++ and then translating it to ARM assembly. This recursive approach to implementing the Euclidean algorithm allows for a clearer and more straightforward translation from higher level languages to raw assembly code.

Implementing the GCD Algorithm in ARM Assembly

Translating C++ Base Case to Assembly

We begin by translating the base case from our C++ code to ARM assembly, where we compare the value B to zero and return the value of A if B is indeed zero.

CMP R1, #0 // compare B to zero
BEQ end_gcd // branch if equal to end gcd

Dealing with Recursive Case

Moving on to the recursive case, we then compute the gcd of B and A mod B. However, ARM v7 assembly does not have a built-in modulus operator, so we manually perform the necessary steps to compute the remainder.

This provides us with the A mod B result, which we can then use to make the recursive call.

SDIV R2, R0, R1 // a / b
MUL R3, R2, R1  // division result * b
SUB R4, R1, R3  // a - previous product
MOV R0, R1      // move old B value to new A value
MOV R1, R4      // move a mod b to new B value
BL gcd          // branch with link to gcd

Conclusion

In conclusion, we successfully implemented the recursive approach to computing the gcd using the Euclidean algorithm in raw ARM assembly. This demonstrates the step-by-step process of translating C++ code to assembly and highlights the intricacies involved in dealing with specific ARM assembly functionalities.

Key Takeaways

FAQ
What is the Euclidean algorithm used for?
The Euclidean algorithm is commonly used to compute the greatest common divisor (gcd) of two integers.

Thank you for watching and we hope you enjoy implementing the Euclidean algorithm in raw ARM assembly!