Commit e8b6fa70 authored by Wei Yongjun's avatar Wei Yongjun Committed by Avi Kivity
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KVM: x86 emulator: add CBW/CWDE/CDQE instruction emulation 



Add CBW/CWDE/CDQE instruction emulation.(opcode 0x98)
Used by FreeBSD's boot loader.

Signed-off-by: default avatarWei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 0fa6ccbd

arch/x86/kvm/emulate.c

+8 −1
Original line number Diff line number Diff line
@@ -2300,7 +2300,7 @@ static struct opcode opcode_table[256] = { 
	/* 0x90 - 0x97 */

	X8(D(SrcAcc | DstReg)),

	/* 0x98 - 0x9F */

	N, N, D(SrcImmFAddr | No64), N,

	D(DstAcc | SrcNone), N, 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),
@@ -3003,6 +3003,13 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt) 
		if (c->dst.addr.reg == &c->regs[VCPU_REGS_RAX])

			break;

		goto xchg;

	case 0x98: /* cbw/cwde/cdqe */

		switch (c->op_bytes) {

		case 2: c->dst.val = (s8)c->dst.val; break;

		case 4: c->dst.val = (s16)c->dst.val; break;

		case 8: c->dst.val = (s32)c->dst.val; break;

		}

		break;

	case 0x9c: /* pushf */

		c->src.val =  (unsigned long) ctxt->eflags;

		emulate_push(ctxt, ops);