KVM: x86 emulator: add bsf/bsr instruction emulation
Add bsf/bsr instruction emulation (opcode 0x0f 0xbc~0xbd)
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 8617c34..f6b124f 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2379,8 +2379,8 @@
/* 0xB8 - 0xBF */
N, N,
G(BitOp, group8), D(DstMem | SrcReg | ModRM | BitOp | Lock),
- N, N, D(ByteOp | DstReg | SrcMem | ModRM | Mov),
- D(DstReg | SrcMem16 | ModRM | Mov),
+ D(DstReg | SrcMem | ModRM), D(DstReg | SrcMem | ModRM),
+ D(ByteOp | DstReg | SrcMem | ModRM | Mov), D(DstReg | SrcMem16 | ModRM | Mov),
/* 0xC0 - 0xCF */
N, N, N, D(DstMem | SrcReg | ModRM | Mov),
N, N, N, GD(0, &group9),
@@ -3511,6 +3511,30 @@
btc: /* btc */
emulate_2op_SrcV_nobyte("btc", c->src, c->dst, ctxt->eflags);
break;
+ case 0xbc: { /* bsf */
+ u8 zf;
+ __asm__ ("bsf %2, %0; setz %1"
+ : "=r"(c->dst.val), "=q"(zf)
+ : "r"(c->src.val));
+ ctxt->eflags &= ~X86_EFLAGS_ZF;
+ if (zf) {
+ ctxt->eflags |= X86_EFLAGS_ZF;
+ c->dst.type = OP_NONE; /* Disable writeback. */
+ }
+ break;
+ }
+ case 0xbd: { /* bsr */
+ u8 zf;
+ __asm__ ("bsr %2, %0; setz %1"
+ : "=r"(c->dst.val), "=q"(zf)
+ : "r"(c->src.val));
+ ctxt->eflags &= ~X86_EFLAGS_ZF;
+ if (zf) {
+ ctxt->eflags |= X86_EFLAGS_ZF;
+ c->dst.type = OP_NONE; /* Disable writeback. */
+ }
+ break;
+ }
case 0xbe ... 0xbf: /* movsx */
c->dst.bytes = c->op_bytes;
c->dst.val = (c->d & ByteOp) ? (s8) c->src.val :