public inbox for kvm@vger.kernel.org
 help / color / mirror / Atom feed
From: Wei Yongjun <yjwei@cn.fujitsu.com>
To: Avi Kivity <avi@redhat.com>
Cc: kvm@vger.kernel.org
Subject: [PATCH] KVM: x86 emulator: simplify two-byte opcode check
Date: Thu, 05 Aug 2010 16:34:39 +0800	[thread overview]
Message-ID: <4C5A779F.5070902@cn.fujitsu.com> (raw)

Two-byte opcode always start with 0x0F and the decode flags
of opcode 0xF0 is always 0, so remove dup check.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
---
 arch/x86/kvm/emulate.c |   12 +++++-------
 1 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 8763708..a465823 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2405,13 +2405,11 @@ done_prefixes:
 
 	/* Opcode byte(s). */
 	opcode = opcode_table[c->b];
-	if (opcode.flags == 0) {
-		/* Two-byte opcode? */
-		if (c->b == 0x0f) {
-			c->twobyte = 1;
-			c->b = insn_fetch(u8, 1, c->eip);
-			opcode = twobyte_table[c->b];
-		}
+	/* Two-byte opcode? */
+	if (c->b == 0x0f) {
+		c->twobyte = 1;
+		c->b = insn_fetch(u8, 1, c->eip);
+		opcode = twobyte_table[c->b];
 	}
 	c->d = opcode.flags;
 
-- 
1.7.0.4



             reply	other threads:[~2010-08-05  8:36 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-08-05  8:34 Wei Yongjun [this message]
2010-08-05  8:48 ` [PATCH] KVM: x86 emulator: simplify two-byte opcode check Avi Kivity

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4C5A779F.5070902@cn.fujitsu.com \
    --to=yjwei@cn.fujitsu.com \
    --cc=avi@redhat.com \
    --cc=kvm@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox