mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2025-01-24 12:35:55 +08:00
96f842cbdb
This commit adds support to RISC-V GDB for vector registers in the incoming target description. The vector registers should be described in a feature called "org.gnu.gdb.riscv.vector", and should contain the register v0 to v31. There's no restriction on the size or type of these registers, so the target description can set these up as it requires. However, if the target feature is present then all of the registers must be present, and they must all be the same size, these requirements are, I believe, inline with the RISC-V vector extension. The DWARF register numbers for the vector registers have been added, and the code to map between GDB's internal numbering and the DWARF numbering has been updated. I have not yet added a feature/riscv/*.xml file for the vector extension, the consequence of this is that we can't, right now, detect vector registers on a native target, this patch is all about supporting vectors on a remote target. It is worth noting that I don't actually have access to a RISC-V target with vectors, so the only testing that this patch has had has been done using 'set tdesc filename ....' to load a target description to which I have manually added the vector feature. This has shown that the vector register feature can be successfully parsed, and that the registers show up in the expected register groups. Additionally, the RISC-V vector extension is currently at v0.10, which is also the v1.0 draft release. However, this extension is not yet finalised. It is possible (but unlikely I think) that the register set could change between now and the final release of the vector extension. If this were to happen then we would potentially end up changing the requirements for the new org.gnu.gdb.riscv.vector feature. I really don't think it is likely that the register set will change this late in the process, and even if it did, changing the feature requirements will not be a problem as far as I am concerned (when the alternative is GDB just continues without this feature for now). gdb/ChangeLog: * NEWS: Mention new target feature name. * arch/riscv.c (riscv_create_target_description): GDB doesn't currently create target descriptions containing vector registers. * arch/riscv.h (struct riscv_gdbarch_features) <vlen>: New member variable. <operator==>: Also compare vlen. <hash>: Also include vlen. * riscv-tdep.c (riscv_feature_name_vector): New static global. (struct riscv_vector_feature): New struct. (riscv_vector_feature): New static global. (riscv_register_reggroup_p): Ensure vector registers are part of the 'all' group, and part of the 'vector' group. (riscv_dwarf_reg_to_regnum): Handle vector registers. (riscv_gdbarch_init): Check vector register feature. * riscv-tdep.h: Add vector registers to GDB's internal register numbers, and to the DWARF register numbers. gdb/doc/ChangeLog: * gdb.texinfo (RISC-V Features): Mention vector register feature.
107 lines
3.7 KiB
C++
107 lines
3.7 KiB
C++
/* Common target-dependent functionality for RISC-V
|
|
|
|
Copyright (C) 2018-2021 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_RISCV_H
|
|
#define ARCH_RISCV_H
|
|
|
|
#include "gdbsupport/tdesc.h"
|
|
|
|
/* The set of RISC-V architectural features that we track that impact how
|
|
we configure the actual gdbarch instance. We hold one of these in the
|
|
gdbarch_tdep structure, and use it to distinguish between different
|
|
RISC-V gdbarch instances.
|
|
|
|
The information in here ideally comes from the target description,
|
|
however, if the target doesn't provide a target description then we will
|
|
create a default target description by first populating one of these
|
|
based on what we know about the binary being executed, and using that to
|
|
drive default target description creation. */
|
|
|
|
struct riscv_gdbarch_features
|
|
{
|
|
/* The size of the x-registers in bytes. This is either 4 (RV32), 8
|
|
(RV64), or 16 (RV128). No other value is valid. Initialise to the
|
|
invalid 0 value so we can spot if one of these is used
|
|
uninitialised. */
|
|
int xlen = 0;
|
|
|
|
/* The size of the f-registers in bytes. This is either 4 (RV32), 8
|
|
(RV64), or 16 (RV128). This can also hold the value 0 to indicate
|
|
that there are no f-registers. No other value is valid. */
|
|
int flen = 0;
|
|
|
|
/* The size of the v-registers in bytes. The value 0 indicates a target
|
|
with no vector registers. The minimum value for a standard compliant
|
|
target should be 16, but GDB doesn't currently mind, and will accept
|
|
any vector size. */
|
|
int vlen = 0;
|
|
|
|
/* When true this target is RV32E. */
|
|
bool embedded = false;
|
|
|
|
/* Equality operator. */
|
|
bool operator== (const struct riscv_gdbarch_features &rhs) const
|
|
{
|
|
return (xlen == rhs.xlen && flen == rhs.flen
|
|
&& embedded == rhs.embedded && vlen == rhs.vlen);
|
|
}
|
|
|
|
/* Inequality operator. */
|
|
bool operator!= (const struct riscv_gdbarch_features &rhs) const
|
|
{
|
|
return !((*this) == rhs);
|
|
}
|
|
|
|
/* Used by std::unordered_map to hash feature sets. */
|
|
std::size_t hash () const noexcept
|
|
{
|
|
std::size_t val = ((embedded ? 1 : 0) << 10
|
|
| (xlen & 0x1f) << 5
|
|
| (flen & 0x1f) << 0
|
|
| (vlen & 0xfff) << 11);
|
|
return val;
|
|
}
|
|
};
|
|
|
|
#ifdef GDBSERVER
|
|
|
|
/* Create and return a target description that is compatible with FEATURES.
|
|
This is only used directly from the gdbserver where the created target
|
|
description is modified after it is return. */
|
|
|
|
target_desc_up riscv_create_target_description
|
|
(const struct riscv_gdbarch_features features);
|
|
|
|
#else
|
|
|
|
/* Lookup an already existing target description matching FEATURES, or
|
|
create a new target description if this is the first time we have seen
|
|
FEATURES. For the same FEATURES the same target_desc is always
|
|
returned. This is important when trying to lookup gdbarch objects as
|
|
GDBARCH_LIST_LOOKUP_BY_INFO performs a pointer comparison on target
|
|
descriptions to find candidate gdbarch objects. */
|
|
|
|
const target_desc *riscv_lookup_target_description
|
|
(const struct riscv_gdbarch_features features);
|
|
|
|
#endif /* GDBSERVER */
|
|
|
|
|
|
#endif /* ARCH_RISCV_H */
|