Author: imp
Date: Thu May 24 21:11:28 2018
New Revision: 334182
URL: https://svnweb.freebsd.org/changeset/base/334182

Log:
  Define memmove and make bcopy alt entry point
  
  Make a memmove entry point just before bcopy and have it swap its args
  before continuing into the body of bcopy. Adjust the returns to return
  dst (original %o0 swapped to %o1) from both entry points. bcopy users
  will ignore them. Since these are in the branch delay slot, it should
  take no additional time. I use %o6 for this rather than just move %o1
  back to %o2 at the end since my sparc64 assembler knowledge is weak.
  Also eliminate wrapper call from memmove to bcopy.
  
  Differential Revision: https://reviews.freebsd.org/D15374

Modified:
  head/sys/conf/files.sparc64
  head/sys/sparc64/sparc64/support.S

Modified: head/sys/conf/files.sparc64
==============================================================================
--- head/sys/conf/files.sparc64 Thu May 24 21:11:24 2018        (r334181)
+++ head/sys/conf/files.sparc64 Thu May 24 21:11:28 2018        (r334182)
@@ -71,7 +71,6 @@ libkern/ffsll.c                       standard
 libkern/fls.c                  standard
 libkern/flsl.c                 standard
 libkern/flsll.c                        standard
-libkern/memmove.c              standard
 sparc64/central/central.c      optional        central
 sparc64/ebus/ebus.c            optional        ebus
 sparc64/ebus/epic.c            optional        epic ebus

Modified: head/sys/sparc64/sparc64/support.S
==============================================================================
--- head/sys/sparc64/sparc64/support.S  Thu May 24 21:11:24 2018        
(r334181)
+++ head/sys/sparc64/sparc64/support.S  Thu May 24 21:11:28 2018        
(r334182)
@@ -265,10 +265,18 @@ ENTRY(bcmp)
 END(bcmp)
 
 /*
+ * void *memmove(void *dst, const void *src, size_t len)
  * void bcopy(const void *src, void *dst, size_t len)
  */
-ENTRY(bcopy)
+ENTRY(memmove)
        /*
+        * Swap src/dst for memmove/bcopy differences
+        */
+       mov     %o0, %o6
+       mov     %o1, %o0
+       mov     %o6, %o1
+ALTENTRY(bcopy)
+       /*
         * Check for overlap, and copy backwards if so.
         */
        sub     %o1, %o0, %g1
@@ -290,15 +298,15 @@ ENTRY(bcopy)
        ba      %xcc, 1b
         stb    %g1, [%o1]
 2:     retl
-        nop
+        mov    %o6, %o0
 
        /*
         * Do the fast version.
         */
 3:     _MEMCPY(%o1, %o0, %o2, EMPTY, EMPTY, EMPTY, EMPTY)
        retl
-        nop
-END(bcopy)
+        mov    %o6, %o0
+END(memmove)
 
 /*
  * void bzero(void *b, size_t len)
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