gdb/arm: Terminate unwinding when LR is 0xffffffff

ARMv7-M Architecture Reference "A2.3.1 Arm core registers" states
that LR is set to 0xffffffff on reset.

ARMv8-M Architecture Reference "B3.3 Registers" states that LR is set
to 0xffffffff on warm reset if Main Extension is implemented,
otherwise the value is unknown.

Signed-off-by: Torbjörn SVENSSON <torbjorn.svensson@st.com>
Signed-off-by: Yvan Roux <yvan.roux@foss.st.com>
This commit is contained in:
Yvan Roux
2022-06-09 16:31:40 +02:00
parent 575a212a78
commit 148ca9dd5c

View File

@ -3330,6 +3330,17 @@ arm_m_exception_cache (struct frame_info *this_frame)
lr = get_frame_register_unsigned (this_frame, ARM_LR_REGNUM);
sp = get_frame_register_unsigned (this_frame, ARM_SP_REGNUM);
/* ARMv7-M Architecture Reference "A2.3.1 Arm core registers"
states that LR is set to 0xffffffff on reset. ARMv8-M Architecture
Reference "B3.3 Registers" states that LR is set to 0xffffffff on warm
reset if Main Extension is implemented, otherwise the value is unknown. */
if (lr == 0xffffffff)
{
/* Terminate any further stack unwinding by referring to self. */
arm_cache_set_active_sp_value (cache, tdep, sp);
return cache;
}
fnc_return = ((lr & 0xfffffffe) == 0xfefffffe);
if (tdep->have_sec_ext && fnc_return)
{