From: Harald van Dijk <[email protected]>
trans_BRA does
gen_a64_set_pc(s, dst);
set_btype_for_br(s, a->rn);
gen_a64_set_pc does
s->pc_save = -1;
set_btype_for_br (if aa64_bti is enabled and the register is not x16 or
x17) does
gen_pc_plus_diff(s, pc, 0);
gen_pc_plus_diff does
assert(s->pc_save != -1);
Hence, this assert is getting hit. We need to call set_btype_for_br
before gen_a64_set_pc, and there is nothing in set_btype_for_br that
depends on gen_a64_set_pc having already been called, so this commit
simply swaps the calls.
(The commit message for 64678fc45d8f6 says that set_brtype_for_br()
must be "moved after" get_a64_set_pc(), but this is a mistake in
the commit message -- the actual changes in that commit move
set_brtype_for_br() *before* get_a64_set_pc() and this is necessary
to avoid the assert.)
Cc: [email protected]
Fixes: 64678fc45d8f6 ("target/arm: Fix BTI versus CF_PCREL")
Signed-off-by: Harald van Dijk <[email protected]>
Reviewed-by: Peter Maydell <[email protected]>
Reviewed-by: Richard Henderson <[email protected]>
Message-id: [email protected]
[PMM: added note about 64678fc45d8f6 to commit message]
Signed-off-by: Peter Maydell <[email protected]>
---
target/arm/tcg/translate-a64.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index 08b21d7dbfa..cde22a5cca7 100644
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -1916,8 +1916,8 @@ static bool trans_BRA(DisasContext *s, arg_bra *a)
return false;
}
dst = auth_branch_target(s, cpu_reg(s,a->rn), cpu_reg_sp(s, a->rm), !a->m);
- gen_a64_set_pc(s, dst);
set_btype_for_br(s, a->rn);
+ gen_a64_set_pc(s, dst);
s->base.is_jmp = DISAS_JUMP;
return true;
}
--
2.43.0
