From 52811d7de565b2db988257591fbf2a6be31c1459 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Mon, 26 Jul 2010 14:37:48 +0300 Subject: [PATCH] KVM: x86 emulator: mix decode bits from opcode and group decode tables Allow bits that are common to all members of a group to be specified in the opcode table instead of the group table. This allows some simplification of the decode tables. Signed-off-by: Avi Kivity Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/emulate.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index b1e3e8c2aff..ef2b5af33a3 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -955,7 +955,7 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) struct decode_cache *c = &ctxt->decode; int rc = X86EMUL_CONTINUE; int mode = ctxt->mode; - int def_op_bytes, def_ad_bytes, group; + int def_op_bytes, def_ad_bytes, group, dual; /* we cannot decode insn before we complete previous rep insn */ @@ -1055,14 +1055,16 @@ done_prefixes: if (c->d & Group) { group = c->d & GroupMask; + dual = c->d & GroupDual; c->modrm = insn_fetch(u8, 1, c->eip); --c->eip; group = (group << 3) + ((c->modrm >> 3) & 7); - if ((c->d & GroupDual) && (c->modrm >> 6) == 3) - c->d = group2_table[group]; + c->d &= ~(Group | GroupDual | GroupMask); + if (dual && (c->modrm >> 6) == 3) + c->d |= group2_table[group]; else - c->d = group_table[group]; + c->d |= group_table[group]; } /* Unrecognised? */ -- 2.41.0