From 57dcb643d79731b08a863444d6591d22552bc2e5 Mon Sep 17 00:00:00 2001 From: Pavel Dovgalyuk Date: Tue, 11 May 2021 12:11:43 +0300 Subject: [PATCH] replay: fix watchpoint processing for reverse debugging This patch enables reverse debugging with watchpoints. Reverse continue scans the execution to find the breakpoints and watchpoints that should fire. It uses helper function replay_breakpoint() for that. But this function needs to access icount, which can't be correct in the middle of TB. Therefore, in case of watchpoint, we have to retranslate the block to allow this access. Signed-off-by: Pavel Dovgalyuk Message-Id: <162072430303.827403.7379783546934958566.stgit@pasha-ThinkPad-X280> Signed-off-by: Richard Henderson --- softmmu/physmem.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/softmmu/physmem.c b/softmmu/physmem.c index e1da81ed2f..1c8717684a 100644 --- a/softmmu/physmem.c +++ b/softmmu/physmem.c @@ -904,6 +904,16 @@ void cpu_check_watchpoint(CPUState *cpu, vaddr addr, vaddr len, if (watchpoint_address_matches(wp, addr, len) && (wp->flags & flags)) { if (replay_running_debug()) { + /* + * replay_breakpoint reads icount. + * Force recompile to succeed, because icount may + * be read only at the end of the block. + */ + if (!cpu->can_do_io) { + /* Force execution of one insn next time. */ + cpu->cflags_next_tb = 1 | CF_LAST_IO | curr_cflags(cpu); + cpu_loop_exit_restore(cpu, ra); + } /* * Don't process the watchpoints when we are * in a reverse debugging operation.