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| author | Yao Qi <yao.qi@linaro.org> | 2015-10-15 15:05:10 +0100 |
|---|---|---|
| committer | Yao Qi <yao.qi@linaro.org> | 2015-10-15 15:05:10 +0100 |
| commit | 8d689ee570e7c4c61231b919d5b6a34c20414c43 (patch) | |
| tree | a59fd53387fcfe5b81d4a89e52b6f4441cbd1f08 /gdb/common | |
| parent | 21c40443ce8b12faa085149ba8a30b33193f6cc7 (diff) | |
| download | gdb-8d689ee570e7c4c61231b919d5b6a34c20414c43.zip gdb-8d689ee570e7c4c61231b919d5b6a34c20414c43.tar.gz gdb-8d689ee570e7c4c61231b919d5b6a34c20414c43.tar.bz2 | |
aarch64 multi-arch part 6: HW breakpoint on unaligned address
Nowadays, both aarch64 GDB and linux kernel assumes that address for
setting breakpoint should be 4-byte aligned. However that is not true
after we support multi-arch, because thumb instruction can be at 2-byte
aligned address. Patch http://lists.infradead.org/pipermail/linux-arm-kernel/2015-October/375141.html
to linux kernel is to teach kernel to handle 2-byte aligned address for
HW breakpoint, while this patch is to teach aarch64 GDB handle 2-byte
aligned address.
First of all, we call gdbarch_breakpoint_from_pc to get the instruction
length rather than using hard-coded 4. Secondly, in GDBserver, we set
length back to 2 if it is 3, because GDB encode 3 in it to indicate it
is a 32-bit thumb breakpoint. Then we relax the address alignment
check from 4-byte aligned to 2-byte aligned.
This patch enables some tests (such as gdb.base/break-idempotent.exp,
gdb.base/cond-eval-mode.exp, gdb.base/watchpoint-reuse-slot.exp,) and
fixes many fails (such as gdb.base/hbreak2.exp) when the program is
compiled in thumb mode on aarch64.
Regression tested on aarch64-linux, both native and gdbserver. This
is the last patch of multi-arch work.
gdb:
2015-10-15 Yao Qi <yao.qi@linaro.org>
* aarch64-linux-nat.c (aarch64_linux_insert_hw_breakpoint):
Call gdbarch_breakpoint_from_pc to instruction length.
(aarch64_linux_remove_hw_breakpoint): Likewise.
* common/common-regcache.h (regcache_register_size): Declare.
* nat/aarch64-linux-hw-point.c: Include "common-regcache.h".
(aarch64_point_is_aligned): Set alignment to 2 for breakpoint if
the process is 32bit, otherwise set alignment to 4.
(aarch64_handle_breakpoint): Update comments.
* regcache.c (regcache_register_size): New function.
gdb/gdbserver:
2015-10-15 Yao Qi <yao.qi@linaro.org>
* linux-aarch64-low.c (aarch64_insert_point): Set len to 2
if it is 3.
(aarch64_remove_point): Likewise.
* regcache.c (regcache_register_size): New function.
Diffstat (limited to 'gdb/common')
| -rw-r--r-- | gdb/common/common-regcache.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/gdb/common/common-regcache.h b/gdb/common/common-regcache.h index a922316..c470603 100644 --- a/gdb/common/common-regcache.h +++ b/gdb/common/common-regcache.h @@ -28,6 +28,11 @@ extern struct regcache *get_thread_regcache_for_ptid (ptid_t ptid); +/* Return the size of register numbered N in REGCACHE. This function + must be provided by the client. */ + +extern int regcache_register_size (const struct regcache *regcache, int n); + /* Read the PC register. This function must be provided by the client. */ |