Add ARM64 NEON support to compute benchmark suite

[Copilot]

Adds ARM64 NEON intrinsics alongside existing x86-64 SSE2 to enable native SIMD acceleration on both architectures.

Implementation

Architecture detection:

#if defined(__x86_64__) || defined(__amd64__)
  #include <immintrin.h>
  #define USE_X86_SIMD 1
  #define USE_ARM_NEON 0
#elif defined(__aarch64__) || defined(__ARM_NEON)
  #include <arm_neon.h>
  #define USE_X86_SIMD 0
  #define USE_ARM_NEON 1
#endif

SIMD operations migrated:

• Matrix multiplication: _mm_mul_pd/_mm_add_pd → vfmaq_f64 (fused multiply-add)
• String search: _mm_cmpeq_epi8/_mm_movemask_epi8 → vceqq_u8 + array extraction
• Memory copy: _mm_loadu_si128/_mm_storeu_si128 → vld1q_u8/vst1q_u8
• Hashing: SSE2 byte extraction → NEON 16-byte vectorized processing
• Polynomial eval: SSE2 horizontal operations → vaddvq_f64

Lane index fix:
Both SSE2 _mm_extract_epi16 and NEON vgetq_lane_u8 require compile-time constant indices. Replaced with:

// Store vector to array, then loop with runtime index
alignas(16) uint8_t bytes[16];
vst1q_u8(bytes, chunk);
for (int j = 0; j < 16; j++) {
    hash = ((hash << 5) + hash) + bytes[j];
}

Modified files:

• 5 compute modules: matrix_operations, hash_operations, string_search, memory_operations, polynomial_eval
• main.cpp: architecture banner detection
• Dockerfile: multi-arch build support
• README.md: ARM64 documentation

The codebase now compiles and runs natively on both x86-64 (SSE2) and ARM64 (NEON) with appropriate vectorization for each platform.

Warning

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I tried to connect to the following addresses, but was blocked by firewall rules:

• esm.ubuntu.com
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If you need me to access, download, or install something from one of these locations, you can either:

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Original prompt

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This section details on the original issue you should resolve

<issue_title>migrate this repo to arm</issue_title>
<issue_description>use the arm mcp server.</issue_description>

Comments on the Issue (you are @copilot in this section)

Custom agent used: arm-migration-agent
Scan a project and migrate to ARM architecture

• Fixes migrate this repo to arm #10

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