<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/109396>109396</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Floating-point constant to unsigned integer error
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          bmq7911
      </td>
    </tr>
</table>

<pre>
    When using clang (-O3) to convert a floating point constant such as -1234.56 into an unsigned integer and then printing out the converted result with printf, it produces a random value; whereas when using gcc(-O3) it outputs 0 instead.
```
#include <stdio.h>
int main(int argc, char * argv[]) {
    float x = -1234.56;
    unsigned int res = (unsigned int)x;
    printf("res: %u\n", res);
    return 0;
}
```
 I have observed that when optimizing with -O3 flag, constant folding occurs during the EarlyCSE pass. However, during conversion within IEEEFloat module fails and results in oplnvalidOp which causes the conversion result to become poison. As a consequence of this poisoned parameter being passed through esi register according to x64 ABI standard rules , there exists an IMPLICIT_DEF statement assigning a value to rsi register which gets removed later on during processimpdefs pass leading ultimately leads producing random values being printed by printf function call . Do you know if there are any solutions available for this issue?
</pre>
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