From 61429142802b068609ffd8ef48d891e05eeea0b9 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Thu, 19 Aug 2010 15:13:00 +0300 Subject: [PATCH] KVM: x86 emulator: implement CWD (opcode 99) Signed-off-by: Avi Kivity --- arch/x86/kvm/emulate.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 55849c3d5d8c..e257f2286866 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -2280,6 +2280,18 @@ static int em_imul_3op(struct x86_emulate_ctxt *ctxt) return em_imul(ctxt); } +static int em_cwd(struct x86_emulate_ctxt *ctxt) +{ + struct decode_cache *c = &ctxt->decode; + + c->dst.type = OP_REG; + c->dst.bytes = c->src.bytes; + c->dst.addr.reg = &c->regs[VCPU_REGS_RDX]; + c->dst.val = ~((c->src.val >> (c->src.bytes * 8 - 1)) - 1); + + return X86EMUL_CONTINUE; +} + static int em_rdtsc(struct x86_emulate_ctxt *ctxt) { unsigned cpl = ctxt->ops->cpl(ctxt->vcpu); @@ -2425,7 +2437,8 @@ static struct opcode opcode_table[256] = { /* 0x90 - 0x97 */ X8(D(SrcAcc | DstReg)), /* 0x98 - 0x9F */ - D(DstAcc | SrcNone), N, D(SrcImmFAddr | No64), N, + D(DstAcc | SrcNone), I(ImplicitOps | SrcAcc, em_cwd), + D(SrcImmFAddr | No64), N, D(ImplicitOps | Stack), D(ImplicitOps | Stack), N, N, /* 0xA0 - 0xA7 */ D(ByteOp | DstAcc | SrcMem | Mov | MemAbs), D(DstAcc | SrcMem | Mov | MemAbs), -- 2.39.5