From: Julian Seward <jseward@acm.org>
Date: Sat, 12 Mar 2005 16:47:18 +0000 (+0000)
Subject: Deal better with x86 'rep nop' (P4 pause hint).
X-Git-Tag: svn/VALGRIND_3_0_1^2~310
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=6bed55781fb019d6fb4dffd5e6cd8b428c6646a5;p=thirdparty%2Fvalgrind.git

Deal better with x86 'rep nop' (P4 pause hint).


git-svn-id: svn://svn.valgrind.org/vex/trunk@1024
---

diff --git a/VEX/priv/guest-x86/toIR.c b/VEX/priv/guest-x86/toIR.c
index ceb1aaddc3..d56a1363ac 100644
--- a/VEX/priv/guest-x86/toIR.c
+++ b/VEX/priv/guest-x86/toIR.c
@@ -11305,14 +11305,10 @@ DisResult disInstr ( /*IN*/  Bool       resteerOK,
       case 0x90:           /* REP NOP (PAUSE) */
          /* a hint to the P4 re spin-wait loop */
          DIP("rep nop (P4 pause)\n");
-#        if 0
-         /* "observe" the hint.  Can cause very long delays, though. */
+         /* "observe" the hint.  The Vex client needs to be careful not
+            to cause very long delays as a result, though. */
          jmp_lit(Ijk_Yield, ((Addr32)guest_eip_bbstart)+delta);
          whatNext = Dis_StopHere;
-#        else
-         /* act like it's a no-op */
-         whatNext = Dis_Continue;
-#        endif
          break;
 
 //--       case 0xC3:           /* REP RET */