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authorStephan Broyles <sbroyles@us.ibm.com>2014-11-05 19:09:37 -0600
committerStephan Broyles <sbroyles@us.ibm.com>2014-11-05 19:22:32 -0600
commit9976c207cdb20871880bd2f4cf123cf4cb6a8b0f (patch)
tree1cf9ed8f23085e6fe3e0e6046fc30dcb7e02ccf2 /src/lib/memcpy.c
parent2f8ce357b89d361b5091d88aea91416011b73ccb (diff)
downloadtalos-occ-9976c207cdb20871880bd2f4cf123cf4cb6a8b0f.tar.gz
talos-occ-9976c207cdb20871880bd2f4cf123cf4cb6a8b0f.zip
Added remaining occ files.
Change-Id: I91a748d3dcf3161a6a3eedcb376fcaf1e4dfe655
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+// $Id: memcpy.c,v 1.1.1.1 2013/12/11 20:49:20 bcbrock Exp $
+// $Source: /afs/awd/projects/eclipz/KnowledgeBase/.cvsroot/eclipz/chips/p8/working/procedures/lib/memcpy.c,v $
+//-----------------------------------------------------------------------------
+// *! (C) Copyright International Business Machines Corp. 2013
+// *! All Rights Reserved -- Property of IBM
+// *! *** IBM Confidential ***
+//-----------------------------------------------------------------------------
+
+/// \file memcpy.c
+/// \brief The memcpy() function
+
+#include "ssx.h"
+
+/// The memcpy() function copies \a n bytes from memory area \a src to memory
+/// area \a dest. The memory areas should not overlap. Use memmove(3) if the
+/// memory areas do overlap. The memcpy() function returns a pointer to dest.
+
+// This implementation should work well for both 32-bit and 64-bit machines,
+// assuming they can handle unaligned accesses. The implementation assumes that
+// it is better to avoid the loop setup overhead by a test and branch for
+// cases where loops can be bypassed.
+
+//void *
+//memcpy(void *dest, const void *src, size_t n)
+//{
+// while(n--) {
+// *dest++ = *src++;
+// }
+//
+// return s;
+//}
+
+void *
+memcpy(void *dest, const void *src, size_t n)
+{
+ uint8_t *d8, *s8;
+ uint64_t *d64, *s64;
+ size_t doublewords, octawords;
+
+ // First copy memory 32 bytes at a time.
+
+ d64 = (uint64_t *)dest;
+ s64 = (uint64_t *)src;
+ octawords = n / 32;
+ if (octawords) {
+ n -= octawords * 32;
+ while(octawords--) {
+ *d64++ = *s64++;
+ *d64++ = *s64++;
+ *d64++ = *s64++;
+ *d64++ = *s64++;
+ }
+ }
+
+ // Now set memory 8 bytes at a time. This might actually be better done
+ // explicitly rather than as a loop because the maximum loop count is 3
+ // here.
+
+ doublewords = n / 8;
+ if (doublewords) {
+ n -= doublewords * 8;
+ while (doublewords--) {
+ *d64++ = *s64++;
+ }
+ }
+
+ // Finally finish any remaining memory bytewise
+
+ if (n) {
+ d8 = (uint8_t *)d64;
+ s8 = (uint8_t *)s64;
+ while (n--) {
+ *d8++ = *s8++;
+ }
+ }
+
+ return dest;
+}
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