From ff227392cd7b858b2b04732e02697122fd1b35b0 Mon Sep 17 00:00:00 2001 From: Takuya Yoshikawa Date: Tue, 22 Nov 2011 15:21:33 +0900 Subject: [PATCH] KVM: x86 emulator: Use opcode::execute for BSF/BSR BSF: 0F BC BSR: 0F BD Signed-off-by: Takuya Yoshikawa Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/emulate.c | 60 +++++++++++++++++++++++++++++--------------------- 1 file changed, 35 insertions(+), 25 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 799000d..4cd3313 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -2921,6 +2921,40 @@ static int em_btc(struct x86_emulate_ctxt *ctxt) return X86EMUL_CONTINUE; } +static int em_bsf(struct x86_emulate_ctxt *ctxt) +{ + u8 zf; + + __asm__ ("bsf %2, %0; setz %1" + : "=r"(ctxt->dst.val), "=q"(zf) + : "r"(ctxt->src.val)); + + ctxt->eflags &= ~X86_EFLAGS_ZF; + if (zf) { + ctxt->eflags |= X86_EFLAGS_ZF; + /* Disable writeback. */ + ctxt->dst.type = OP_NONE; + } + return X86EMUL_CONTINUE; +} + +static int em_bsr(struct x86_emulate_ctxt *ctxt) +{ + u8 zf; + + __asm__ ("bsr %2, %0; setz %1" + : "=r"(ctxt->dst.val), "=q"(zf) + : "r"(ctxt->src.val)); + + ctxt->eflags &= ~X86_EFLAGS_ZF; + if (zf) { + ctxt->eflags |= X86_EFLAGS_ZF; + /* Disable writeback. */ + ctxt->dst.type = OP_NONE; + } + return X86EMUL_CONTINUE; +} + static bool valid_cr(int nr) { switch (nr) { @@ -3428,7 +3462,7 @@ static struct opcode twobyte_table[256] = { N, N, G(BitOp, group8), I(DstMem | SrcReg | ModRM | BitOp | Lock | PageTable, em_btc), - D(DstReg | SrcMem | ModRM), D(DstReg | SrcMem | ModRM), + I(DstReg | SrcMem | ModRM, em_bsf), I(DstReg | SrcMem | ModRM, em_bsr), D(ByteOp | DstReg | SrcMem | ModRM | Mov), D(DstReg | SrcMem16 | ModRM | Mov), /* 0xC0 - 0xCF */ D2bv(DstMem | SrcReg | ModRM | Lock), @@ -4176,30 +4210,6 @@ twobyte_insn: ctxt->dst.val = (ctxt->d & ByteOp) ? (u8) ctxt->src.val : (u16) ctxt->src.val; break; - case 0xbc: { /* bsf */ - u8 zf; - __asm__ ("bsf %2, %0; setz %1" - : "=r"(ctxt->dst.val), "=q"(zf) - : "r"(ctxt->src.val)); - ctxt->eflags &= ~X86_EFLAGS_ZF; - if (zf) { - ctxt->eflags |= X86_EFLAGS_ZF; - ctxt->dst.type = OP_NONE; /* Disable writeback. */ - } - break; - } - case 0xbd: { /* bsr */ - u8 zf; - __asm__ ("bsr %2, %0; setz %1" - : "=r"(ctxt->dst.val), "=q"(zf) - : "r"(ctxt->src.val)); - ctxt->eflags &= ~X86_EFLAGS_ZF; - if (zf) { - ctxt->eflags |= X86_EFLAGS_ZF; - ctxt->dst.type = OP_NONE; /* Disable writeback. */ - } - break; - } case 0xbe ... 0xbf: /* movsx */ ctxt->dst.bytes = ctxt->op_bytes; ctxt->dst.val = (ctxt->d & ByteOp) ? (s8) ctxt->src.val : -- 2.7.4