tools/pldt/org.eclipse.ptp.pldt.upc/html/upc_all_gather_all.html

<h2>The <code>upc_all_gather_all</code> function</h2>

<h4>Synopsis</h4>
<pre>    
    #include &lt;upc.h&gt;
    #include &lt;upc_collective.h&gt;
    void upc_all_gather_all(shared void * restrict dst,
                            shared const void * restrict src, 
                            size_t nbytes,
                            upc_flag_t flags);
</pre>
<p>
<h4>Description</h4>
<p>
The <code>upc_all_gather_all </code>  function 
copies a block of memory from one shared
memory area with affinity to the ith thread to the ith block of a shared
memory area on each thread. The number of bytes in each block is <code>nbytes</code>.
<p><code>nbytes</code> must be strictly greater than 0.
<p>The upc_all_gather_all function treats the <code>src</code> pointer as if it pointed to a
shared memory area of <code>nbytes</code> bytes on each thread and therefore had type:
<pre>
shared [nbytes] char[nbytes * THREADS]
</pre>
<p>and it treats the <code>dst</code>  pointer as if it pointed to a shared memory area with
the type:
shared [nbytes * THREADS] char[nbytes * THREADS * THREADS]
<p>The targets of the <code>src</code> and <code>dst</code> pointers must have affinity to thread 0.
<p>The <code>src</code> and <code>dst</code>  pointers are treated as if they have phase 0.
<p>The effect is equivalent to copying the ith block of <code>nbytes</code> bytes pointed to
by <code>src</code> to the ith block of <code>nbytes</code> bytes pointed to by <code>dst</code> that has affinity
to each thread.



<p>
<ul>
<li> EXAMPLE 1 <code>upc_all_gather_all </code> for the static THREADS translation environment.
<pre>
#include &lt;upc.h&gt;
#include &lt;upc_collective.h&gt;
#define NELEMS 10
shared [NELEMS] int A[NELEMS*THREADS];
shared [NELEMS*THREADS] int B[THREADS][NELEMS*THREADS];
// Initialize A.
upc_barrier;
upc_all_gather_all( B, A, sizeof(int)*NELEMS,
UPC_IN_NOSYNC | UPC_OUT_NOSYNC );
upc_barrier;
</pre>
<li>EXAMPLE 2 <code>upc_all_gather_all </code> all for the dynamic THREADS translation
environment.
<pre>
#include &lt;upc.h&gt;
#include &lt;upc_collective.h&gt;
#define NELEMS 10
shared [NELEMS] int A[NELEMS*THREADS];
shared int *Bdata;
shared [] int *myB;
Bdata = upc_all_alloc(THREADS*THREADS, NELEMS*sizeof(int));
myB = (shared [] int *)&Bdata[MYTHREAD];
// Bdata contains THREADS*THREADS*NELEMS elements.
// myB is MYTHREADÕs row of Bdata.
// Initialize A.
upc_all_gather_all( Bdata, A, NELEMS*sizeof(int),
UPC_IN_ALLSYNC | UPC_OUT_ALLSYNC );
</pre>
<li>
<li>
</ul>
<p>&nbsp
<p>&nbsp
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