binutils-gdb/gdb/arch/aarch64.h
Luis Machado 7fd8546853 [AArch64] Make gdbserver register set selection dynamic
The current register set selection mechanism for AArch64 is static, based
on a pre-populated array of register sets.

This means that we might potentially probe register sets that are not
available. This is OK if the kernel errors out during ptrace, but probing the
tag_ctl register, for example, does not result in a ptrace error if the kernel
supports the tagged address ABI but not MTE (PR 28355).

Making the register set selection dynamic, based on feature checks, solves
this and simplifies the code a bit. It allows us to list all of the register
sets only once, and pick and choose based on HWCAP/HWCAP2 or other properties.

I plan to backport this fix to GDB 11 as well.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28355
2021-11-03 09:50:53 -03:00

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C

/* Common target-dependent functionality for AArch64.
Copyright (C) 2017-2021 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 ARCH_AARCH64_H
#define ARCH_AARCH64_H
#include "gdbsupport/tdesc.h"
/* Holds information on what architectural features are available. This is
used to select register sets. */
struct aarch64_features
{
bool sve = false;
bool pauth = false;
bool mte = false;
};
/* Create the aarch64 target description. A non zero VQ value indicates both
the presence of SVE and the Vector Quotient - the number of 128bit chunks in
an SVE Z register. HAS_PAUTH_P indicates the presence of the PAUTH
feature.
MTE_P indicates the presence of the Memory Tagging Extension feature. */
target_desc *aarch64_create_target_description (uint64_t vq, bool has_pauth_p,
bool mte_p);
/* Register numbers of various important registers.
Note that on SVE, the Z registers reuse the V register numbers and the V
registers become pseudo registers. */
enum aarch64_regnum
{
AARCH64_X0_REGNUM, /* First integer register. */
AARCH64_FP_REGNUM = AARCH64_X0_REGNUM + 29, /* Frame register, if used. */
AARCH64_LR_REGNUM = AARCH64_X0_REGNUM + 30, /* Return address. */
AARCH64_SP_REGNUM, /* Stack pointer. */
AARCH64_PC_REGNUM, /* Program counter. */
AARCH64_CPSR_REGNUM, /* Current Program Status Register. */
AARCH64_V0_REGNUM, /* First fp/vec register. */
AARCH64_V31_REGNUM = AARCH64_V0_REGNUM + 31, /* Last fp/vec register. */
AARCH64_SVE_Z0_REGNUM = AARCH64_V0_REGNUM, /* First SVE Z register. */
AARCH64_SVE_Z31_REGNUM = AARCH64_V31_REGNUM, /* Last SVE Z register. */
AARCH64_FPSR_REGNUM, /* Floating Point Status Register. */
AARCH64_FPCR_REGNUM, /* Floating Point Control Register. */
AARCH64_SVE_P0_REGNUM, /* First SVE predicate register. */
AARCH64_SVE_P15_REGNUM = AARCH64_SVE_P0_REGNUM + 15, /* Last SVE predicate
register. */
AARCH64_SVE_FFR_REGNUM, /* SVE First Fault Register. */
AARCH64_SVE_VG_REGNUM, /* SVE Vector Granule. */
/* Other useful registers. */
AARCH64_LAST_X_ARG_REGNUM = AARCH64_X0_REGNUM + 7,
AARCH64_STRUCT_RETURN_REGNUM = AARCH64_X0_REGNUM + 8,
AARCH64_LAST_V_ARG_REGNUM = AARCH64_V0_REGNUM + 7
};
#define V_REGISTER_SIZE 16
/* Pseudo register base numbers. */
#define AARCH64_Q0_REGNUM 0
#define AARCH64_D0_REGNUM (AARCH64_Q0_REGNUM + AARCH64_D_REGISTER_COUNT)
#define AARCH64_S0_REGNUM (AARCH64_D0_REGNUM + 32)
#define AARCH64_H0_REGNUM (AARCH64_S0_REGNUM + 32)
#define AARCH64_B0_REGNUM (AARCH64_H0_REGNUM + 32)
#define AARCH64_SVE_V0_REGNUM (AARCH64_B0_REGNUM + 32)
#define AARCH64_PAUTH_DMASK_REGNUM(pauth_reg_base) (pauth_reg_base)
#define AARCH64_PAUTH_CMASK_REGNUM(pauth_reg_base) (pauth_reg_base + 1)
#define AARCH64_PAUTH_REGS_SIZE (16)
#define AARCH64_X_REGS_NUM 31
#define AARCH64_V_REGS_NUM 32
#define AARCH64_SVE_Z_REGS_NUM AARCH64_V_REGS_NUM
#define AARCH64_SVE_P_REGS_NUM 16
#define AARCH64_NUM_REGS AARCH64_FPCR_REGNUM + 1
#define AARCH64_SVE_NUM_REGS AARCH64_SVE_VG_REGNUM + 1
/* There are a number of ways of expressing the current SVE vector size:
VL : Vector Length.
The number of bytes in an SVE Z register.
VQ : Vector Quotient.
The number of 128bit chunks in an SVE Z register.
VG : Vector Granule.
The number of 64bit chunks in an SVE Z register. */
#define sve_vg_from_vl(vl) ((vl) / 8)
#define sve_vl_from_vg(vg) ((vg) * 8)
#ifndef sve_vq_from_vl
#define sve_vq_from_vl(vl) ((vl) / 0x10)
#endif
#ifndef sve_vl_from_vq
#define sve_vl_from_vq(vq) ((vq) * 0x10)
#endif
#define sve_vq_from_vg(vg) (sve_vq_from_vl (sve_vl_from_vg (vg)))
#define sve_vg_from_vq(vq) (sve_vg_from_vl (sve_vl_from_vq (vq)))
/* Maximum supported VQ value. Increase if required. */
#define AARCH64_MAX_SVE_VQ 16
#endif /* ARCH_AARCH64_H */