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          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - We should only expect a RareCaseProfile to exist if the rare case actually exists"
   href="https://bugs.webkit.org/show_bug.cgi?id=149531">149531</a>
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        <tr>
          <th>Summary</th>
          <td>We should only expect a RareCaseProfile to exist if the rare case actually exists
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
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        <tr>
          <th>Product</th>
          <td>WebKit
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>WebKit Local Build
          </td>
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          <th>Hardware</th>
          <td>Unspecified
          </td>
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          <th>OS</th>
          <td>Unspecified
          </td>
        </tr>

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          <th>Status</th>
          <td>NEW
          </td>
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          <th>Severity</th>
          <td>Normal
          </td>
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          <th>Priority</th>
          <td>P2
          </td>
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          <th>Component</th>
          <td>JavaScriptCore
          </td>
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        <tr>
          <th>Assignee</th>
          <td>webkit-unassigned&#64;lists.webkit.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>mark.lam&#64;apple.com
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      <p>
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        <pre>The current code that calls rareCaseProfileForBytecodeOffset() always assumes that it will always return a non-null RareCaseProfile.  As a result, op_add in the baseline JIT is forced to add a dummy slow case that will never be taken, only to ensure that the RareCaseProfile for that bytecode is created, and it will always produce a counter value of 0 (since that path will never be taken).  Instead, we'll make the callers of rareCaseProfileForBytecodeOffset() check if the profile actually exist before dereferencing it.</pre>
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