<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Issue</th>
<td>
<a href=https://github.com/llvm/llvm-project/issues/185558>185558</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>
Missed Optimization: Failure to vectorize scalar loads and comparisons into a single vector operation
</td>
</tr>
<tr>
<th>Labels</th>
<td>
new issue
</td>
</tr>
<tr>
<th>Assignees</th>
<td>
</td>
</tr>
<tr>
<th>Reporter</th>
<td>
dreamking60
</td>
</tr>
</table>
<pre>
```
define i1 @src(ptr %arg0, ptr %arg1) {
%v0 = load <2 x float>, ptr %arg1, align 8
%v1 = load float, ptr %arg0, align 4
%v2 = extractelement <2 x float> %v0, i64 0
%v3 = fcmp une float %v1, %v2
%v4 = getelementptr inbounds nuw i8, ptr %arg0, i64 4
%v5 = load float, ptr %v4, align 4
%v6 = extractelement <2 x float> %v0, i64 1
%v7 = fcmp une float %v5, %v6
%v8 = select i1 %v3, i1 true, i1 %v7
ret i1 %v8
}
define i1 @tgt(ptr %arg0, ptr %arg1) {
%vec_arg0 = load <2 x float>, ptr %arg0, align 4
%vec_arg1 = load <2 x float>, ptr %arg1, align 8
%cmp_result_vec = fcmp une <2 x float> %vec_arg0, %vec_arg1
%res0 = extractelement <2 x i1> %cmp_result_vec, i64 0
%res1 = extractelement <2 x i1> %cmp_result_vec, i64 1
%final_res = select i1 %res0, i1 true, i1 %res1
ret i1 %final_res
}
```
godbolt: https://godbolt.org/z/TE1czre66
alive2: https://alive2.llvm.org/ce/z/eqjwqJ
Pattern found in: https://github.com/dtcxzyw/llvm-opt-benchmark/blob/main/bench/pbrt-v4/optimized/imgtool.ll
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJyklE2P4yYYxz8NvqCJAL_OwYfZmfWhUtUeeh9heOKwi8ELOJnNp6_AjtOZZFfbVooiA8_v_7wC914NBqBF5SdUvmR8DgfrWumAj1-VGSqS9VZ-b1FF1h95krBXBrCiGBXEO4FYMwWHESu5Gwhiz_i6pIg9YlR_QuQp7hwJRvkL1pZLjPJnht_wXlseUP75hnvGXKvB4CayCaZXeKHeIeSKFBvCEgJvwXERQMMIJnz0vAQWaVUVmGxsnti9GCc8G1jMlziibVLfbItkO8DFRwxLmd7ORnps5hNWzZ1oo7_iUpryx9kdi3u5Vf86N7qx9Y9yKy-5VZttk2w9aBAhdT3WJklSHNwM62eSTZCDzS42D9Uv8f_D4IQh_OrgJCUQr9HqF-fn7jAsEvR_jKAYp1cHftbh9QjifQ3vVX4N-lLTNYCLmgNPftJDRVeZ915vBtWBp_9dZotmrwzX0eC23THQuw2Prj-0fJO5dv4fb8dgZW91QPkTPoQweZQ_IdYh1q0HO-sGxLozYt1fn6k4O6jiIHKtjsBuqWV_p_VxXEkBKw7fvpy-_bYM3p88BHAG7-N9xMrcca_CYe53wo6IdTKIt_P3E2JdFH6wU3jowYjDyN1XxLpe2x6xbuTKxFU8Qaybehce4kXt7BTUqM4gEevUOARr9U7rTLa5fMwfeQYtreucUkKrMju0ed3Xsu_LouRcNqJsZFFLxnJRCy65KDLVMsIqklNCWF6RctdLmtdclJSziuc9RwWBkSu91SFT3s_Q0qYsyybTvAft0wvPmIETTqeIsfjguzbl2M-DRwXRygd_lQkqaGh_V96DxH8safGgbCpgx5WeHeBg8RFEsE6dAXvBNXfpdnnMjcTCjhN3ylvjsTLBYo69MoOGFcJ2Apc0s9np9iddiVFdWjI5-wVEiAWOuXjEujXZY8v-DgAA__-N2wse">