[PATCH 2/2 v4] KVM: x86 emulator: add XADD instruction emulation

Wei Yongjun
2010-08-17T01:22:06Z

Add XADD instruction emulation (opcode 0x0f 0xc0~0xc1)

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
---
arch/x86/kvm/emulate.c | 9 ++++++++-
1 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index d690daf..41ca98b 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2386,7 +2386,8 @@ static struct opcode twobyte_table[256] = {
D(DstReg | SrcMem | ModRM), D(DstReg | SrcMem | ModRM),
D(ByteOp | DstReg | SrcMem | ModRM | Mov), D(DstReg | SrcMem16 | ModRM | Mov),
/* 0xC0 - 0xCF */
- N, N, N, D(DstMem | SrcReg | ModRM | Mov),
+ D(ByteOp | DstMem | SrcReg | ModRM | Lock), D(DstMem | SrcReg | ModRM | Lock),
+ N, D(DstMem | SrcReg | ModRM | Mov),
N, N, N, GD(0, &group9),
N, N, N, N, N, N, N, N,
/* 0xD0 - 0xDF */
@@ -3532,6 +3533,12 @@ twobyte_insn:
c->dst.val = (c->d & ByteOp) ? (s8) c->src.val :
(s16) c->src.val;
break;
+ case 0xc0 ... 0xc1: /* xadd */
+ emulate_2op_SrcV("add", c->src, c->dst, ctxt->eflags);
+ /* Write back the register source. */
+ c->src.val = c->dst.orig_val;
+ write_register_operand(&c->src);
+ break;
case 0xc3: /* movnti */
c->dst.bytes = c->op_bytes;
c->dst.val = (c->op_bytes == 4) ? (u32) c->src.val :
--
1.7.0.4