<html>
<head>
<base href="http://llvm.org/bugs/" />
</head>
<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - avx2 gather_epi64 intrinsics have wrong pointer type"
href="http://llvm.org/bugs/show_bug.cgi?id=17312">17312</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>avx2 gather_epi64 intrinsics have wrong pointer type
</td>
</tr>
<tr>
<th>Product</th>
<td>clang
</td>
</tr>
<tr>
<th>Version</th>
<td>3.3
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
<tr>
<th>OS</th>
<td>Linux
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>C++
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>agner@agner.org
</td>
</tr>
<tr>
<th>CC</th>
<td>dgregor@apple.com, llvmbugs@cs.uiuc.edu
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr></table>
<p>
<div>
<pre>The definition of the following intrinsics in avx2intrin.h is problematic:
_mm_i32gather_epi64
_mm256_i32gather_epi64
_mm_i64gather_epi64
_mm256_i64gather_epi64
_mm_mask_i32gather_epi64
_mm256_mask_i32gather_epi64
_mm_mask_i64gather_epi64
_mm256_mask_i64gather_epi64
The base pointer for these intrinsics (named m in clang version of
avx2intrin.h) has type int const *. This is in accordance with the official
Intel documents, which are wrong. The correct type is a pointer to 64-bit
integers. Intel and Microsoft versions of this intrinsic use the type const
__int64 *, which is not defined in any C standard. The Gnu compiler uses the
type const long long *. I would recommend using the type const long long * for
the sake of compatibility with the Gnu compiler.
See gcc patch:
<a href="http://gcc.gnu.org/ml/gcc-patches/2011-06/msg01793/avx2.gatherdecls.gcc.patch">http://gcc.gnu.org/ml/gcc-patches/2011-06/msg01793/avx2.gatherdecls.gcc.patch</a>
Test case:
typedef const long long * ppp;
// typedef const int * ppp;
__m128i VPGATHERDQ1(ppp base, __m128i index) {
return _mm_i32gather_epi64 (base, index, 1);
}
__m256i VPGATHERDQ2 (ppp base, __m128i index) {
return _mm256_i32gather_epi64 (base, index, 2);
}
__m128i VPGATHERQQ1(ppp base, __m128i index) {
return _mm_i64gather_epi64 (base, index, 4);
}
__m128i VPGATHERQQ2(ppp base, __m128i index) {
return _mm256_i64gather_epi64 ( base, index, 8);
}</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are on the CC list for the bug.</li>
</ul>
</body>
</html>