From 31be40b3985f09c0c89b9e28a8206df32adba842 Mon Sep 17 00:00:00 2001 From: Wei Yongjun Date: Tue, 17 Aug 2010 09:17:30 +0800 Subject: [PATCH] KVM: x86 emulator: put register operand write back to a function Introduce function write_register_operand() to write back the register operand. Signed-off-by: Wei Yongjun Signed-off-by: Avi Kivity --- arch/x86/kvm/emulate.c | 55 +++++++++++++++++++++----------------------------- 1 file changed, 23 insertions(+), 32 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index f6b124f..0037130 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -1020,6 +1020,25 @@ exception: return X86EMUL_PROPAGATE_FAULT; } +static void write_register_operand(struct operand *op) +{ + /* The 4-byte case *is* correct: in 64-bit mode we zero-extend. */ + switch (op->bytes) { + case 1: + *(u8 *)op->addr.reg = (u8)op->val; + break; + case 2: + *(u16 *)op->addr.reg = (u16)op->val; + break; + case 4: + *op->addr.reg = (u32)op->val; + break; /* 64b: zero-extend */ + case 8: + *op->addr.reg = op->val; + break; + } +} + static inline int writeback(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) { @@ -1029,23 +1048,7 @@ static inline int writeback(struct x86_emulate_ctxt *ctxt, switch (c->dst.type) { case OP_REG: - /* The 4-byte case *is* correct: - * in 64-bit mode we zero-extend. - */ - switch (c->dst.bytes) { - case 1: - *(u8 *)c->dst.addr.reg = (u8)c->dst.val; - break; - case 2: - *(u16 *)c->dst.addr.reg = (u16)c->dst.val; - break; - case 4: - *c->dst.addr.reg = (u32)c->dst.val; - break; /* 64b: zero-ext */ - case 8: - *c->dst.addr.reg = c->dst.val; - break; - } + write_register_operand(&c->dst); break; case OP_MEM: if (c->lock_prefix) @@ -2970,25 +2973,13 @@ special_insn: case 0x86 ... 0x87: /* xchg */ xchg: /* Write back the register source. */ - switch (c->dst.bytes) { - case 1: - *(u8 *) c->src.addr.reg = (u8) c->dst.val; - break; - case 2: - *(u16 *) c->src.addr.reg = (u16) c->dst.val; - break; - case 4: - *c->src.addr.reg = (u32) c->dst.val; - break; /* 64b reg: zero-extend */ - case 8: - *c->src.addr.reg = c->dst.val; - break; - } + c->src.val = c->dst.val; + write_register_operand(&c->src); /* * Write back the memory destination with implicit LOCK * prefix. */ - c->dst.val = c->src.val; + c->dst.val = c->src.orig_val; c->lock_prefix = 1; break; case 0x88 ... 0x8b: /* mov */ -- 2.7.4