Commit d77a2507 authored by Nitin A Kamble's avatar Nitin A Kamble Committed by Avi Kivity
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KVM: x86 emulator: Implement emulation of instruction: inc & dec 



Instructions:
	inc r16/r32 (opcode 0x40-0x47)
	dec r16/r32 (opcode 0x48-0x4f)

Signed-off-by: default avatarNitin A Kamble <nitin.a.kamble@intel.com>
Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent 3176bc3e

drivers/kvm/x86_emulate.c

+18 −2
Original line number Diff line number Diff line
@@ -96,8 +96,12 @@ static u8 opcode_table[256] = { 
	ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,

	ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,

	0, 0, 0, 0,

	/* 0x40 - 0x4F */

	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

	/* 0x40 - 0x47 */

	ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,

	ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,

	/* 0x48 - 0x4F */

	ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,

	ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,

	/* 0x50 - 0x57 */

	ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,

	ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
@@ -1376,6 +1380,18 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
	if (c->twobyte)

		goto twobyte_special_insn;

	switch (c->b) {

	case 0x40 ... 0x47: /* inc r16/r32 */

		c->dst.bytes = c->op_bytes;

		c->dst.ptr = (unsigned long *)&c->regs[c->b & 0x7];

		c->dst.val = *c->dst.ptr;

		emulate_1op("inc", c->dst, ctxt->eflags);

		break;

	case 0x48 ... 0x4f: /* dec r16/r32 */

		c->dst.bytes = c->op_bytes;

		c->dst.ptr = (unsigned long *)&c->regs[c->b & 0x7];

		c->dst.val = *c->dst.ptr;

		emulate_1op("dec", c->dst, ctxt->eflags);

		break;

	case 0x50 ... 0x57:  /* push reg */

		if (c->op_bytes == 2)

			c->src.val = (u16) c->regs[c->b & 0x7];