@@ -2410,6 +2410,24 @@ static void gen_reset_hflag(DisasContext *s, uint32_t mask)
}
}
+/* Clear BND registers during legacy branches. */
+static void gen_bnd_jmp(DisasContext *s)
+{
+ /* Do nothing if BND prefix present, MPX is disabled, BNDPRESERVE is set,
+ or if the BNDREGs are known to be in INIT state already. */
+ if ((s->prefix & PREFIX_REPNZ) == 0
+ && (s->flags & HF_MPX_EN_MASK) == 0
+ && (s->flags & HF_MPX_PR_MASK) == 0
+ && (s->flags & HF_MPX_IU_MASK) == 0) {
+ int i;
+ for (i = 0; i < 4; ++i) {
+ tcg_gen_movi_i64(cpu_bndl[i], 0);
+ tcg_gen_movi_i64(cpu_bndu[i], 0);
+ }
+ gen_reset_hflag(s, HF_MPX_IU_MASK);
+ }
+}
+
/* generate a generic end of block. Trace exception is also generated
if needed */
static void gen_eob(DisasContext *s)
@@ -4832,6 +4850,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
tcg_gen_movi_tl(cpu_T1, next_eip);
gen_push_v(s, cpu_T1);
gen_op_jmp_v(cpu_T0);
+ gen_bnd_jmp(s);
gen_eob(s);
break;
case 3: /* lcall Ev */
@@ -4859,6 +4878,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
tcg_gen_ext16u_tl(cpu_T0, cpu_T0);
}
gen_op_jmp_v(cpu_T0);
+ gen_bnd_jmp(s);
gen_eob(s);
break;
case 5: /* ljmp Ev */
@@ -6260,6 +6280,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
gen_stack_update(s, val + (1 << ot));
/* Note that gen_pop_T0 uses a zero-extending load. */
gen_op_jmp_v(cpu_T0);
+ gen_bnd_jmp(s);
gen_eob(s);
break;
case 0xc3: /* ret */
@@ -6267,6 +6288,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
gen_pop_update(s, ot);
/* Note that gen_pop_T0 uses a zero-extending load. */
gen_op_jmp_v(cpu_T0);
+ gen_bnd_jmp(s);
gen_eob(s);
break;
case 0xca: /* lret im */
@@ -6335,6 +6357,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
}
tcg_gen_movi_tl(cpu_T0, next_eip);
gen_push_v(s, cpu_T0);
+ gen_bnd_jmp(s);
gen_jmp(s, tval);
}
break;
@@ -6364,6 +6387,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
} else if (!CODE64(s)) {
tval &= 0xffffffff;
}
+ gen_bnd_jmp(s);
gen_jmp(s, tval);
break;
case 0xea: /* ljmp im */
@@ -6403,6 +6427,7 @@ static target_ulong disas_insn(CPUX86State *env, DisasContext *s,
if (dflag == MO_16) {
tval &= 0xffff;
}
+ gen_bnd_jmp(s);
gen_jcc(s, b, tval, next_eip);
break;
Signed-off-by: Richard Henderson <rth@twiddle.net> --- target-i386/translate.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+)