On 3 November 2015 at 09:02, Sergey Fedorov <[email protected]> wrote: > On 02.11.2015 21:28, Peter Maydell wrote: >> On 2 November 2015 at 17:51, Sergey Fedorov <[email protected]> wrote: >>> CPU singlestep is done by generating a debug internal exception. Do not >>> raise a real CPU exception in case of singlestepping. >>> >>> Signed-off-by: Sergey Fedorov <[email protected]> >>> --- >>> target-arm/op_helper.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/target-arm/op_helper.c b/target-arm/op_helper.c >>> index 7929c71..67d9ffb 100644 >>> --- a/target-arm/op_helper.c >>> +++ b/target-arm/op_helper.c >>> @@ -909,7 +909,7 @@ void arm_debug_excp_handler(CPUState *cs) >>> uint64_t pc = is_a64(env) ? env->pc : env->regs[15]; >>> bool same_el = (arm_debug_target_el(env) == arm_current_el(env)); >>> >>> - if (cpu_breakpoint_test(cs, pc, BP_GDB)) { >>> + if (cs->singlestep_enabled || cpu_breakpoint_test(cs, pc, BP_GDB)) >>> { >>> return; >>> } >> So I think this will mean that if we're gdbstub-single-stepping then >> an architectural breakpoint on the insn we're stepping won't fire. >> >> Does using a test >> >> if (!cpu_breakpoint_test(cs, pc, BP_CPU)) { >> return; >> } >> >> fix the singlestep bug too? If so I think it would probably be >> preferable. > > Actually, it is supposed that gdbstub breakpoints should be handled > before CPU breakpoints. So I think we should rather do this way: > > if (cpu_breakpoint_test(cs, pc, BP_GDB) || !cpu_breakpoint_test(cs, pc, > BP_CPU)) { > return; > }
Yes, that sounds like the right logic. I think a comment will be helpful to explain what's going on for future readers :-) thanks -- PMM
