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    <body><span class="vcard"><a class="email" href="mailto:kenneth@whitecape.org" title="Kenneth Graunke <kenneth@whitecape.org>"> <span class="fn">Kenneth Graunke</span></a>
</span> changed
          <a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - [CTS] GTF-GL46.gtf32.GL3Tests.packed_pixels.packed_pixels tests fail on 32bit Mesa"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=104395">bug 104395</a>
          <br>
             <table border="1" cellspacing="0" cellpadding="8">
          <tr>
            <th>What</th>
            <th>Removed</th>
            <th>Added</th>
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         <tr>
           <td style="text-align:right;">CC</td>
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           </td>
           <td>mattst88@gmail.com
           </td>
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      <p>
        <div>
            <b><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - [CTS] GTF-GL46.gtf32.GL3Tests.packed_pixels.packed_pixels tests fail on 32bit Mesa"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=104395#c1">Comment # 1</a>
              on <a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - [CTS] GTF-GL46.gtf32.GL3Tests.packed_pixels.packed_pixels tests fail on 32bit Mesa"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=104395">bug 104395</a>
              from <span class="vcard"><a class="email" href="mailto:kenneth@whitecape.org" title="Kenneth Graunke <kenneth@whitecape.org>"> <span class="fn">Kenneth Graunke</span></a>
</span></b>
        <pre>This basically boils down to:

   _mesa_lroundevenf(0.571428597f * 0xffffffffu)

returning wildly different results on 64-bit and 32-bit.

64-bit: result = 0x92492500
32-bit: result = 0x80000000

This happens even if I use the lrintf path directly instead of the SSE
intrinsics.

----------------------------------

How to arrive at this conclusion:

1. Simplify the test to do less work:
   a. Comment out all "formats" other than GL_RED
   b. Comment out all "types" other than GL_SHORT and GL_UNSIGNED_INT
3. Break in get_tex_rgba_uncompressed
   We should be doing a R16_SNORM -> R32_UNORM conversion here

4. Note the conversion to RGBA32_FLOAT for transfer ops
5. Observe that texgetimage.c:546 _mesa_format_convert has the same float
source data in both 32-bit and 64-bit builds, but produces different R32_UNORM
result data.</pre>
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