Hi Alan,
Just some quick comments.
I get this when building on x86-64 with --enable-targets=all:
CXX aarch64-tdep.o
In file included from /home/emaisin/src/binutils-gdb/gdb/nat/aarch64-sve-linux-ptrace.h:29:0,
from /home/emaisin/src/binutils-gdb/gdb/aarch64-tdep.c:61:
/home/emaisin/src/binutils-gdb/gdb/nat/aarch64-linux-sigcontext.h:19:22: error: field ‘head’ has incomplete type ‘_aarch64_ctx’
struct _aarch64_ctx head;
^
/home/emaisin/src/binutils-gdb/gdb/nat/aarch64-linux-sigcontext.h:19:9: note: forward declaration of ‘struct _aarch64_ctx’
struct _aarch64_ctx head;
^
First, we should not include "nat/aarch64-sve-linux-ptrace.h" (a file that only makes
sense when building on AArch64) in aarch64-tdep.c, a file built on all architecture
when including the support for AArch64 debugging. It looks like aarch64-tdep.c
needs sve_vq_from_vl. Maybe that definition could be moved to arch/, which can be
included in aarch64-tdep.c.
Then, is the _aarch64_ctx structure guaranteed to be defined on older AArch64 kernels
or should we include it too?
On 2018-06-06 11:16 AM, Alan Hayward wrote:
> A purely virtual class containing functions from gdb/regcache.h
>
> Both the gdb regcache structures and gdbserver regcache inherit
> directly from reg_buffer_common. This will allow for common
> functions which require the use of a regcache.
>
> 2018-06-06 Alan Hayward <alan.hayward@arm.com>
>
> gdb/
> * common/common-regcache.h (reg_buffer_common): New structure.
> * regcache.h (reg_buffer_common:get_register_status) Add override.
> (reg_buffer_common:raw_supply): Add dummy function.
> reg_buffer_common:raw_collect): Likewise
> (readable_regcache:raw_supply) Add override.
> (detached_regcache:raw_collect) Likewise.
>
> gdbserver/
> * regcache.c (new_register_cache): Use new.
> (free_register_cache): Use delete.
> register_data): Use const.
> (supply_register): Call member function.
> (regcache::raw_supply): Replacement for supply_register.
> (collect_register): Call member function.
> (regcache::raw_collect): Replacement for collect_register.
> (regcache::get_register_status): New function.
> * regcache.h (regcache:raw_supply): Add dummy function.
> (regcache:raw_collect): Likewise
> (regcache:get_register_status) Likewise.
> ---
> gdb/common/common-regcache.h | 8 ++++++++
> gdb/gdbserver/regcache.c | 47 ++++++++++++++++++++++++++++++++------------
> gdb/gdbserver/regcache.h | 18 +++++++++++------
> gdb/regcache.h | 19 ++++++++++++++----
> 4 files changed, 69 insertions(+), 23 deletions(-)
>
> diff --git a/gdb/common/common-regcache.h b/gdb/common/common-regcache.h
> index 696ba00955..487da0a7fb 100644
> --- a/gdb/common/common-regcache.h
> +++ b/gdb/common/common-regcache.h
> @@ -62,4 +62,12 @@ extern enum register_status regcache_raw_read_unsigned
>
> ULONGEST regcache_raw_get_unsigned (struct regcache *regcache, int regnum);
>
> +struct reg_buffer_common
> +{
> + virtual ~reg_buffer_common () = default;
> + virtual void raw_supply (int regnum, const void *buf) = 0;
> + virtual void raw_collect (int regnum, void *buf) const = 0;
> + virtual register_status get_register_status (int regnum) const = 0;
> +};
Ideally, we would gather the documentation for these methods here. Where they
are implemented/overriden, we can maybe add a reference such as
/* See struct reg_buffer_common. */
?
> diff --git a/gdb/regcache.h b/gdb/regcache.h
> index 3edddf47e1..b559a10752 100644
> --- a/gdb/regcache.h
> +++ b/gdb/regcache.h
> @@ -139,7 +139,7 @@ typedef struct cached_reg
>
> /* Buffer of registers. */
>
> -class reg_buffer
> +class reg_buffer : public reg_buffer_common
> {
> public:
> reg_buffer (gdbarch *gdbarch, bool has_pseudo);
> @@ -151,13 +151,24 @@ public:
>
> /* Get the availability status of the value of register REGNUM in this
> buffer. */
> - enum register_status get_register_status (int regnum) const;
> + enum register_status get_register_status (int regnum) const override;
>
> virtual ~reg_buffer ()
> {
> xfree (m_registers);
> xfree (m_register_status);
> }
> +
> + virtual void raw_supply (int regnum, const void *buf) override
> + {
> + gdb_assert (false);
> + }
> +
> + virtual void raw_collect (int regnum, void *buf) const override
> + {
> + gdb_assert (false);
> + }
Hmm, I understand why you need to do this right now. But what do you think of the
idea of moving the supply and collect implementations up to reg_buffer? I think
that the supply/collect operations are a good fit to go in reg_buffer. Essentially
they just peek/poke in the buffer. The regcache layer's responsibility is then to
use that register buffer to implement a cache in front of the target registers,
and offer the API to properly read/write registers (including pseudo ones).
For reference here's the patch in the regcache-for-alan branch that did this:
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commitdiff;h=0e04bb35765d2717818dddd88328cb975f417b2c;hp=ca9f66e37913be55abaea44813a768b40673a39a
Simon
@@ -62,4 +62,12 @@ extern enum register_status regcache_raw_read_unsigned
ULONGEST regcache_raw_get_unsigned (struct regcache *regcache, int regnum);
+struct reg_buffer_common
+{
+ virtual ~reg_buffer_common () = default;
+ virtual void raw_supply (int regnum, const void *buf) = 0;
+ virtual void raw_collect (int regnum, void *buf) const = 0;
+ virtual register_status get_register_status (int regnum) const = 0;
+};
+
#endif /* COMMON_REGCACHE_H */
@@ -159,7 +159,7 @@ init_register_cache (struct regcache *regcache,
struct regcache *
new_register_cache (const struct target_desc *tdesc)
{
- struct regcache *regcache = XCNEW (struct regcache);
+ struct regcache *regcache = new struct regcache;
gdb_assert (tdesc->registers_size != 0);
@@ -174,7 +174,7 @@ free_register_cache (struct regcache *regcache)
if (regcache->registers_owned)
free (regcache->registers);
free (regcache->register_status);
- free (regcache);
+ delete regcache;
}
}
@@ -300,7 +300,7 @@ regcache_register_size (const struct regcache *regcache, int n)
}
static unsigned char *
-register_data (struct regcache *regcache, int n, int fetch)
+register_data (const struct regcache *regcache, int n, int fetch)
{
return (regcache->registers
+ find_register_by_number (regcache->tdesc, n).offset / 8);
@@ -312,23 +312,27 @@ register_data (struct regcache *regcache, int n, int fetch)
void
supply_register (struct regcache *regcache, int n, const void *buf)
+{
+ return regcache->raw_supply (n, buf);
+}
+
+void
+regcache::raw_supply (int n, const void *buf)
{
if (buf)
{
- memcpy (register_data (regcache, n, 0), buf,
- register_size (regcache->tdesc, n));
+ memcpy (register_data (this, n, 0), buf, register_size (tdesc, n));
#ifndef IN_PROCESS_AGENT
- if (regcache->register_status != NULL)
- regcache->register_status[n] = REG_VALID;
+ if (register_status != NULL)
+ register_status[n] = REG_VALID;
#endif
}
else
{
- memset (register_data (regcache, n, 0), 0,
- register_size (regcache->tdesc, n));
+ memset (register_data (this, n, 0), 0, register_size (tdesc, n));
#ifndef IN_PROCESS_AGENT
- if (regcache->register_status != NULL)
- regcache->register_status[n] = REG_UNAVAILABLE;
+ if (register_status != NULL)
+ register_status[n] = REG_UNAVAILABLE;
#endif
}
}
@@ -410,10 +414,16 @@ supply_register_by_name (struct regcache *regcache,
void
collect_register (struct regcache *regcache, int n, void *buf)
{
- memcpy (buf, register_data (regcache, n, 1),
- register_size (regcache->tdesc, n));
+ regcache->raw_collect (n, buf);
+}
+
+void
+regcache::raw_collect (int n, void *buf) const
+{
+ memcpy (buf, register_data (this, n, 1), register_size (tdesc, n));
}
+
enum register_status
regcache_raw_read_unsigned (struct regcache *regcache, int regnum,
ULONGEST *val)
@@ -480,3 +490,14 @@ regcache_write_pc (struct regcache *regcache, CORE_ADDR pc)
}
#endif
+
+enum register_status
+regcache::get_register_status (int regnum) const
+{
+#ifndef IN_PROCESS_AGENT
+ gdb_assert (regnum >= 0 && regnum < tdesc->reg_defs.size ());
+ return (enum register_status) (register_status[regnum]);
+#else
+ return REG_VALID;
+#endif
+}
@@ -28,23 +28,29 @@ struct target_desc;
inferior; this is primarily for simplicity, as the performance
benefit is minimal. */
-struct regcache
+struct regcache : public reg_buffer_common
{
/* The regcache's target description. */
- const struct target_desc *tdesc;
+ const struct target_desc *tdesc = nullptr;
/* Whether the REGISTERS buffer's contents are valid. If false, we
haven't fetched the registers from the target yet. Not that this
register cache is _not_ pass-through, unlike GDB's. Note that
"valid" here is unrelated to whether the registers are available
in a traceframe. For that, check REGISTER_STATUS below. */
- int registers_valid;
- int registers_owned;
- unsigned char *registers;
+ int registers_valid = 0;
+ int registers_owned = 0;
+ unsigned char *registers = nullptr;
#ifndef IN_PROCESS_AGENT
/* One of REG_UNAVAILBLE or REG_VALID. */
- unsigned char *register_status;
+ unsigned char *register_status = nullptr;
#endif
+
+ void raw_supply (int regnum, const void *buf) override;
+
+ void raw_collect (int regnum, void *buf) const override;
+
+ enum register_status get_register_status (int regnum) const override;
};
struct regcache *init_register_cache (struct regcache *regcache,
@@ -139,7 +139,7 @@ typedef struct cached_reg
/* Buffer of registers. */
-class reg_buffer
+class reg_buffer : public reg_buffer_common
{
public:
reg_buffer (gdbarch *gdbarch, bool has_pseudo);
@@ -151,13 +151,24 @@ public:
/* Get the availability status of the value of register REGNUM in this
buffer. */
- enum register_status get_register_status (int regnum) const;
+ enum register_status get_register_status (int regnum) const override;
virtual ~reg_buffer ()
{
xfree (m_registers);
xfree (m_register_status);
}
+
+ virtual void raw_supply (int regnum, const void *buf) override
+ {
+ gdb_assert (false);
+ }
+
+ virtual void raw_collect (int regnum, void *buf) const override
+ {
+ gdb_assert (false);
+ }
+
protected:
/* Assert on the range of REGNUM. */
void assert_regnum (int regnum) const;
@@ -235,7 +246,7 @@ public:
{}
/* Supply register REGNUM, whose contents are stored in BUF, to REGCACHE. */
- void raw_supply (int regnum, const void *buf);
+ void raw_supply (int regnum, const void *buf) override;
void raw_supply (int regnum, const reg_buffer &src)
{
@@ -293,7 +304,7 @@ public:
void raw_update (int regnum) override;
/* Collect register REGNUM from REGCACHE and store its contents in BUF. */
- void raw_collect (int regnum, void *buf) const;
+ void raw_collect (int regnum, void *buf) const override;
void raw_collect_integer (int regnum, gdb_byte *addr, int addr_len,
bool is_signed) const;