<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/63082>63082</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [SLP] gcc choose wider vector length than clang for float type
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          vfdff
      </td>
    </tr>
</table>

<pre>
    * test: https://gcc.godbolt.org/z/ebG5fdndY
```
          const float delx = xtmp - x[j].x;
          const float dely = ytmp - x[j].y;
 const float delz = ztmp - x[j].z;
          const float rsq = delx * delx + dely * dely + delz * delz;
```

*  the kernel body of gcc: **VL = 4**
```
        fsub    v30.4s, v22.4s, v30.4s
        zip1 v28.4s, v28.4s, v29.4s
        zip1    v31.4s, v31.4s, v27.4s
 fmul    v29.4s, v30.4s, v30.4s
        fsub    v28.4s, v21.4s, v28.4s
 fsub    v31.4s, v23.4s, v31.4s
        fmla    v29.4s, v28.4s, v28.4s
        fmla    v29.4s, v31.4s, v31.4s
        fdiv    v27.4s, v16.4s, v29.4s
```

*  the kernel body of clang: **VL = 2**
```
.LBB0_8:                                //   Parent Loop BB0_5 Depth=1
        ldrsw   x16, [x15], #4
        add     x16, x6, x16, lsl #4
        ldr     d16, [x16]
        ldr     s17, [x16, #8]
 fsub    v16.2s, v6.2s, v16.2s
        fsub    s17, s7, s17
 fmul    v18.2s, v16.2s, v16.2s
        faddp   s18, v18.2s
 fmadd   s18, s17, s17, s18
        fcmp    s18, s0
        b.ge .LBB0_7
        fdiv    s18, s3, s18   -- float r2inv = 1.0 / rsq;
```

</pre>
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