[Lldb-commits] [PATCH] D96548: [lldb] [Process/FreeBSDRemote] Introduce aarch64 hw break/watchpoint support

Fri Feb 19 09:52:05 PST 2021

mgorny marked 5 inline comments as done.
mgorny added inline comments.

================
Comment at: lldb/source/Plugins/Process/Utility/NativeRegisterContextBreakWatchpoint_arm64.cpp:248
+  // non 8-byte aligned addresses as well.
+  if (addr & 0x07) {
+    uint8_t watch_mask = (addr & 0x07) + size;
----------------
That's something to consider for a followup work but I'm thinking that instead of changing `size` here we could set bit-mask appropriately to watch only the exact bytes we need. If I read the manual correctly (https://developer.arm.com/documentation/ddi0595/2020-12/AArch64-Registers/DBGWCR-n--EL1--Debug-Watchpoint-Control-Registers?lang=en#fieldset_0-12_5), this should be doable.

e.g. if `addr = 0x2002` and `size = 2` ,
we currently set `addr = 0x2000` and `size = 4` and therefore watch `0x2000`..`0x2003`
but we could instead set BAS to `0b00001100` to watch `0x2002`..`0x2003`.

Am I grasping this correctly?

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  https://reviews.llvm.org/D96548/new/

https://reviews.llvm.org/D96548