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[Enhancement] simd count_zero in arm #54937

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Why I'm doing:

What I'm doing:

Fixes #issue

What type of PR is this:

  • BugFix
  • Feature
  • Enhancement
  • Refactor
  • UT
  • Doc
  • Tool

Does this PR entail a change in behavior?

  • Yes, this PR will result in a change in behavior.
  • No, this PR will not result in a change in behavior.

If yes, please specify the type of change:

  • Interface/UI changes: syntax, type conversion, expression evaluation, display information
  • Parameter changes: default values, similar parameters but with different default values
  • Policy changes: use new policy to replace old one, functionality automatically enabled
  • Feature removed
  • Miscellaneous: upgrade & downgrade compatibility, etc.

Checklist:

  • I have added test cases for my bug fix or my new feature
  • This pr needs user documentation (for new or modified features or behaviors)
  • I have added documentation for my new feature or new function
  • This is a backport pr

Bugfix cherry-pick branch check:

  • I have checked the version labels which the pr will be auto-backported to the target branch
    • 3.4
    • 3.3
    • 3.2
    • 3.1
    • 3.0

Signed-off-by: before-Sunrise <[email protected]>
// result[i] = result[i] & 0x1
result = vandq_u32(result, vdupq_n_u32(1));
count += vaddvq_u32(result);
}
#endif

for (; data < end; ++data) {
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The most risky bug in this code is:
The condition defined(__POPCNT__) is unnecessary and incorrect for ARM NEON intrinsics, which do not require the POPCNT feature.

You can modify the code like this:

#elif defined(__ARM_NEON) && defined(__aarch64__)
// Remove the unnecessary check for __POPCNT__
const T* end16 = data + (size / 16 * 16);
for (; data < end16; data += 16) {
    uint8x16_t vdata = vld1q_u8(data);
    // result[i] = vdata[i] == 0 ? 0xFF : 0x00
    uint8x16_t result = vceqq_u8(vdata, vdupq_n_u8(0));
    // result[i] = result[i] & 0x1
    result = vandq_u8(result, vdupq_n_u8(1));
    count += vaddvq_u8(result);
}

...

#elif defined(__ARM_NEON) && defined(__aarch64__)
// Remove the unnecessary check for __POPCNT__
const T* end4 = data + (size / 4 * 4);
for (; data < end4; data += 4) {
    uint32x4_t vdata = vld1q_u32(data);
    // result[i] = vdata[i] == 0 ? 0xFF : 0x00
    uint32x4_t result = vceqq_u32(vdata, vdupq_n_u32(0));
    // result[i] = result[i] & 0x1
    result = vandq_u32(result, vdupq_n_u32(1));
    count += vaddvq_u32(result);
}
#endif

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[Java-Extensions Incremental Coverage Report]

pass : 0 / 0 (0%)

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[FE Incremental Coverage Report]

pass : 0 / 0 (0%)

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[BE Incremental Coverage Report]

pass : 0 / 0 (0%)

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