Explain Compiler Pipeline and LLVM Backend
Company: Qualcomm
Role: Software Engineer
Category: Software Engineering Fundamentals
Difficulty: medium
Interview Round: Technical Screen
Overview: This question evaluates expertise in compiler design and implementation, covering major compiler pipeline stages, common optimization techniques, LLVM backend lowering of intermediate representation into target machine code, and C/C++ specifics such as object layout, ABI and calling conventions, undefined behavior, aliasing, templates, virtual dispatch, and move semantics. It is commonly asked to assess system-level reasoning about correctness, performance, and debugging in compiler engineering, falls under Software Engineering Fundamentals and compiler construction, and tests both conceptual understanding and practical application of low-level language and toolchain concepts.