From 7418027ea4fec276455abd4291558bc58a0a7ba7 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Thu, 1 Jul 2010 09:42:21 -0700 Subject: target-i386: fix xchg rax,r8 We were ignoring REX_B while special-casing NOP, i.e. xchg eax,eax. Signed-off-by: Richard Henderson Signed-off-by: Aurelien Jarno --- target-i386/translate.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'target-i386/translate.c') diff --git a/target-i386/translate.c b/target-i386/translate.c index 708b0a11e9..8cb5cf0b0a 100644 --- a/target-i386/translate.c +++ b/target-i386/translate.c @@ -5293,6 +5293,7 @@ static target_ulong disas_insn(DisasContext *s, target_ulong pc_start) break; case 0x91 ... 0x97: /* xchg R, EAX */ + do_xchg_reg_eax: ot = dflag + OT_WORD; reg = (b & 7) | REX_B(s); rm = R_EAX; @@ -6663,10 +6664,14 @@ static target_ulong disas_insn(DisasContext *s, target_ulong pc_start) /************************/ /* misc */ case 0x90: /* nop */ - /* XXX: xchg + rex handling */ /* XXX: correct lock test for all insn */ - if (prefixes & PREFIX_LOCK) + if (prefixes & PREFIX_LOCK) { goto illegal_op; + } + /* If REX_B is set, then this is xchg eax, r8d, not a nop. */ + if (REX_B(s)) { + goto do_xchg_reg_eax; + } if (prefixes & PREFIX_REPZ) { gen_svm_check_intercept(s, pc_start, SVM_EXIT_PAUSE); } -- cgit v1.2.3-55-g7522