<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Issue</th>
<td>
<a href=https://github.com/llvm/llvm-project/issues/74914>74914</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>
missed optimization for value range
</td>
</tr>
<tr>
<th>Labels</th>
<td>
</td>
</tr>
<tr>
<th>Assignees</th>
<td>
</td>
</tr>
<tr>
<th>Reporter</th>
<td>
k-arrows
</td>
</tr>
</table>
<pre>
Test case:
https://godbolt.org/z/W5v3br4Ga
```cpp
int mod1(int a, int b) {
int v1, v2;
v1 = a ? 12 : 24;
v2 = b ? 3 : 6;
v1 = b ? v1 * 2 : v1;
return v1 % v2;
}
int mod2(int a, int b) {
int v1, v2;
v1 = a ? 12 : 24;
v2 = b ? 2 : 4;
v1 = b ? v1 * 2 : v1;
return v1 % v2;
}
```
GCC can optimize both `mod1` and `mod2`, but Clang fails to optimize `mod1`. I made this example based on the function `mod` of the test program below, but the original is a bit more complex than the example above.
https://github.com/gcc-mirror/gcc/blob/master/gcc/testsuite/gcc.dg/tree-ssa/pr61839_2.c
</pre>
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