mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2025-02-23 13:21:43 +08:00
5add3fce49
With SME, where you have two different vector lengths (vl and svl), it may be the case that the current frame has a set of vector lengths (A) but the signal context has a distinct set of vector lengths (B). In this case, we may run into a situation where GDB attempts to use a gdbarch created for set A, but it is really dealing with a frame that was using set B. This is problematic, specially with SME, because now we have a different number of pseudo-registers and types that gets cached on creation of each gdbarch variation. For AArch64 we really need to be able to use the correct gdbarch for each frame, and I noticed the signal frame (tramp-frame) doesn't have a settable prev_arch field. So it ends up using the default frame_unwind_arch function and eventually calling get_frame_arch (next_frame). That means the previous frame will always have the same gdbarch as the current frame. This patch first refactors the AArch64/Linux signal context code, simplifying it and making it reusable for our purposes of calculating the previous frame's gdbarch. I introduced a struct that holds information that we have found in the signal context, and with which we can make various decisions. Finally, a small change to tramp-frame.c and tramp-frame.h to expose a prev_arch hook that the architecture can set. With this new field, AArch64/Linux can implement a hook that looks at the signal context and infers the gdbarch for the previous frame. Regression-tested on aarch64-linux Ubuntu 22.04/20.04. Approved-By: Simon Marchi <simon.marchi@efficios.com> Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
89 lines
3.2 KiB
C++
89 lines
3.2 KiB
C++
/* Signal trampoline unwinder.
|
|
|
|
Copyright (C) 2004-2023 Free Software Foundation, Inc.
|
|
|
|
This file is part of GDB.
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>. */
|
|
|
|
#ifndef TRAMP_FRAME_H
|
|
#define TRAMP_FRAME_H
|
|
|
|
#include "frame.h"
|
|
#include "frame-unwind.h" /* For frame_prev_arch_ftype. */
|
|
|
|
class frame_info_ptr;
|
|
struct trad_frame_cache;
|
|
|
|
/* A trampoline consists of a small sequence of instructions placed at
|
|
an unspecified location in the inferior's address space. The only
|
|
identifying attribute of the trampoline's address is that it does
|
|
not fall inside an object file's section.
|
|
|
|
The only way to identify a trampoline is to perform a brute force
|
|
examination of the instructions at and around the PC.
|
|
|
|
This module provides a convenient interface for performing that
|
|
operation. */
|
|
|
|
/* A trampoline descriptor. */
|
|
|
|
/* Magic instruction that to mark the end of the signal trampoline
|
|
instruction sequence. */
|
|
#define TRAMP_SENTINEL_INSN ULONGEST_MAX
|
|
|
|
struct tramp_frame
|
|
{
|
|
/* The trampoline's type, some a signal trampolines, some are normal
|
|
call-frame trampolines (aka thunks). */
|
|
enum frame_type frame_type;
|
|
/* The trampoline's entire instruction sequence. It consists of a
|
|
bytes/mask pair. Search for this in the inferior at or around
|
|
the frame's PC. It is assumed that the PC is INSN_SIZE aligned,
|
|
and that each element of TRAMP contains one INSN_SIZE
|
|
instruction. It is also assumed that INSN[0] contains the first
|
|
instruction of the trampoline and hence the address of the
|
|
instruction matching INSN[0] is the trampoline's "func" address.
|
|
The instruction sequence is terminated by
|
|
TRAMP_SENTINEL_INSN. */
|
|
int insn_size;
|
|
struct
|
|
{
|
|
ULONGEST bytes;
|
|
ULONGEST mask;
|
|
} insn[48];
|
|
/* Initialize a trad-frame cache corresponding to the tramp-frame.
|
|
FUNC is the address of the instruction TRAMP[0] in memory. */
|
|
void (*init) (const struct tramp_frame *self,
|
|
frame_info_ptr this_frame,
|
|
struct trad_frame_cache *this_cache,
|
|
CORE_ADDR func);
|
|
/* Return non-zero if the tramp-frame is valid for the PC requested.
|
|
Adjust the PC to point to the address to check the instruction
|
|
sequence against if required. If this is NULL, then the tramp-frame
|
|
is valid for any PC. */
|
|
int (*validate) (const struct tramp_frame *self,
|
|
frame_info_ptr this_frame,
|
|
CORE_ADDR *pc);
|
|
|
|
/* Given the current frame in THIS_FRAME and a frame cache in FRAME_CACHE,
|
|
return the architecture of the previous frame. */
|
|
frame_prev_arch_ftype *prev_arch;
|
|
};
|
|
|
|
void tramp_frame_prepend_unwinder (struct gdbarch *gdbarch,
|
|
const struct tramp_frame *tramp);
|
|
|
|
#endif
|