Comparative Analysis of MSVC and Clang/LLVM Compilation on Windows on Arm

This article compares the MSVC and Clang/LLVM compiler stacks for native ARM64 builds in the Windows on Arm environment on Qualcomm Kryo and Oryon platforms. The study's relevance lies in the transition of the Windows ecosystem toward native ARM64 execution and the growing role of the compiler in determining software efficiency on new Snapdragon X systems. The aim of the study is to conduct a quantitative and qualitative assessment of code-generation differences between the two toolchains for computational workloads with different profiles. The novelty of the work is defined by a systematic cross-microarchitectural comparison of new MSVC and Clang/LLVM versions in the specific Windows on Arm environment, with separation of compiler influence from hardware platform influence. It was established that Clang/LLVM delivers higher performance in most tests in audio and video encoding, sorting, and interpreted code execution, whereas MSVC reveals a pronounced advantage in the isolated NumPy sqrt mathematical kernel on the Oryon architecture. The results confirm that code-generation efficiency depends on workload characteristics and processor microarchitecture. The article will be useful for developers of C/C++ systems, compiler researchers, and software architects targeting Windows on Arm.

Windows on Arm, ARM64, MSVC, Clang, LLVM, compilers

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