evie/android_kernel_oneplus_msm8998
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KVM: x86 emulator: allow specifying group directly in opcode

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Instead of having a group number, store the group table pointer directly in
the opcode.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This commit is contained in:
Avi Kivity 2010-07-29 15:11:39 +03:00
parent 793d5a8d6b
commit 120df8902d
1 changed files with 38 additions and 9 deletions
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47
arch/x86/kvm/emulate.c
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@ -110,10 +110,21 @@ enum {
struct opcode { struct opcode {
u32 flags; u32 flags;
union {
struct opcode *group;
struct group_dual *gdual;
} u;
};
struct group_dual {
struct opcode mod012[8];
struct opcode mod3[8];
}; };
#define D(_y) { .flags = (_y) } #define D(_y) { .flags = (_y) }
#define N D(0) #define N D(0)
#define G(_f, _g) { .flags = ((_f) | Group), .u.group = (_g) }
#define GD(_f, _g) { .flags = ((_f) | Group | GroupDual), .u.gdual = (_g) }
static struct opcode group_table[] = { static struct opcode group_table[] = {
[Group1*8] = [Group1*8] =
@ -331,6 +342,8 @@ static struct opcode twobyte_table[256] = {
#undef D #undef D
#undef N #undef N
#undef G
#undef GD
/* EFLAGS bit definitions. */ /* EFLAGS bit definitions. */
#define EFLG_ID (1<<21) #define EFLG_ID (1<<21)
@ -930,8 +943,8 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
struct decode_cache *c = &ctxt->decode; struct decode_cache *c = &ctxt->decode;
int rc = X86EMUL_CONTINUE; int rc = X86EMUL_CONTINUE;
int mode = ctxt->mode; int mode = ctxt->mode;
int def_op_bytes, def_ad_bytes, group, dual; int def_op_bytes, def_ad_bytes, group, dual, goffset;
struct opcode opcode, *g_mod012, *g_mod3;
/* we cannot decode insn before we complete previous rep insn */ /* we cannot decode insn before we complete previous rep insn */
WARN_ON(ctxt->restart); WARN_ON(ctxt->restart);
@ -1018,15 +1031,16 @@ done_prefixes:
c->op_bytes = 8; /* REX.W */ c->op_bytes = 8; /* REX.W */
/* Opcode byte(s). */ /* Opcode byte(s). */
c->d = opcode_table[c->b].flags; opcode = opcode_table[c->b];
if (c->d == 0) { if (opcode.flags == 0) {
/* Two-byte opcode? */ /* Two-byte opcode? */
if (c->b == 0x0f) { if (c->b == 0x0f) {
c->twobyte = 1; c->twobyte = 1;
c->b = insn_fetch(u8, 1, c->eip); c->b = insn_fetch(u8, 1, c->eip);
c->d = twobyte_table[c->b].flags; opcode = twobyte_table[c->b];
} }
} }
c->d = opcode.flags;
if (c->d & Group) { if (c->d & Group) {
group = c->d & GroupMask; group = c->d & GroupMask;
@ -1034,12 +1048,27 @@ done_prefixes:
c->modrm = insn_fetch(u8, 1, c->eip); c->modrm = insn_fetch(u8, 1, c->eip);
--c->eip; --c->eip;
group = (group << 3) + ((c->modrm >> 3) & 7); if (group) {
g_mod012 = g_mod3 = &group_table[group * 8];
if (c->d & GroupDual)
g_mod3 = &group2_table[group * 8];
} else {
if (c->d & GroupDual) {
g_mod012 = opcode.u.gdual->mod012;
g_mod3 = opcode.u.gdual->mod3;
} else
g_mod012 = g_mod3 = opcode.u.group;
}
c->d &= ~(Group | GroupDual | GroupMask); c->d &= ~(Group | GroupDual | GroupMask);
if (dual && (c->modrm >> 6) == 3)
c->d |= group2_table[group].flags; goffset = (c->modrm >> 3) & 7;
if ((c->modrm >> 6) == 3)
opcode = g_mod3[goffset];
else else
c->d |= group_table[group].flags; opcode = g_mod012[goffset];
c->d |= opcode.flags;
} }
/* Unrecognised? */ /* Unrecognised? */