[3/5] KVM: x86 emulator: Use single stage decoding for POP instructions

Commit Message

Takuya Yoshikawa March 13, 2011, 3:20 p.m. UTC

None

Patch

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index fcc49ef..8295c50 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2224,6 +2224,13 @@  static int em_push_gs(struct x86_emulate_ctxt *ctxt)
 	return X86EMUL_CONTINUE;
 }
 
+static int em_pop(struct x86_emulate_ctxt *ctxt)
+{
+	struct decode_cache *c = &ctxt->decode;
+
+	return emulate_pop(ctxt, ctxt->ops, &c->dst.val, c->op_bytes);
+}
+
 static int em_pop_es(struct x86_emulate_ctxt *ctxt)
 {
 	return emulate_pop_sreg(ctxt, ctxt->ops, VCPU_SREG_ES);
@@ -2558,7 +2565,7 @@  static struct opcode opcode_table[256] = {
 	/* 0x50 - 0x57 */
 	X8(I(SrcReg | Stack, em_push)),
 	/* 0x58 - 0x5F */
-	X8(D(DstReg | Stack)),
+	X8(I(DstReg | Stack, em_pop)),
 	/* 0x60 - 0x67 */
 	D(ImplicitOps | Stack | No64), D(ImplicitOps | Stack | No64),
 	N, D(DstReg | SrcMem32 | ModRM | Mov) /* movsxd (x86/64) */ ,
@@ -3181,10 +3188,6 @@  special_insn:
 	case 0x48 ... 0x4f: /* dec r16/r32 */
 		emulate_1op("dec", c->dst, ctxt->eflags);
 		break;
-	case 0x58 ... 0x5f: /* pop reg */
-	pop_instruction:
-		rc = emulate_pop(ctxt, ops, &c->dst.val, c->op_bytes);
-		break;
 	case 0x60:	/* pusha */
 		rc = emulate_pusha(ctxt, ops);
 		break;
@@ -3294,7 +3297,8 @@  special_insn:
 		c->dst.type = OP_REG;
 		c->dst.addr.reg = &c->eip;
 		c->dst.bytes = c->op_bytes;
-		goto pop_instruction;
+		rc = emulate_pop(ctxt, ops, &c->dst.val, c->op_bytes);
+		break;
 	case 0xc4:		/* les */
 		rc = emulate_load_segment(ctxt, ops, VCPU_SREG_ES);
 		break;