Comment-only change.

git-svn-id: svn://svn.valgrind.org/vex/trunk@982

diff --git a/VEX/priv/host-amd64/hdefs.c b/VEX/priv/host-amd64/hdefs.c
index 8ce6ec4c3285a655f29daf44d5de1adbbfd5f96e..a5588159be4f6957d9c12ab15f29c9e58200b6bd 100644 (file)
--- a/VEX/priv/host-amd64/hdefs.c
+++ b/VEX/priv/host-amd64/hdefs.c
@@ -2732,6 +2732,9 @@ Int emit_AMD64Instr ( UChar* buf, Int nbuf, AMD64Instr* i )
          goto done;
       }
       if (i->Ain.Store.sz == 1) {
+         /* This is one place where it would be wrong to skip emitting
+            a rex byte of 0x40, since the mere presence of rex changes
+            the meaning of the byte register access.  Be careful. */
         *p++ = clearWBit( rexAMode_M( i->Ain.Store.src, i->Ain.Store.dst) );
          *p++ = 0x88;
          p = doAMode_M(p, i->Ain.Store.src, i->Ain.Store.dst);