[3/3] gdbserver: xtensa: add call0 support
Commit Message
Correctly handle a0- registers on requests from remote gdb. This fixes
'Register 1 is not available'
and subsequent assertion in the remote gdb connecting to the gdbserver:
'findvar.c:291: internal-error: value_of_register_lazy:
Assertion `frame_id_p(get_frame_id (frame))' failed.'
The register structure is the same for windowed and call0 ABIs because
currently linux kernel internally requires windowed registers, so they
are always present.
2017-01-18 Max Filippov <jcmvbkbc@gmail.com>
gdb/gdbserver/
* linux-xtensa-low.c (C0_NREGS): New definition.
(xtensa_fill_gregset): Call collect_register for all registers in
a0_regnum..a0_regnum + C0_NREGS range.
(xtensa_store_gregset): Call supply_register for all registers in
a0_regnum..a0_regnum + C0_NREGS range.
---
gdb/gdbserver/linux-xtensa-low.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
Comments
On 01/18/2017 05:50 PM, Max Filippov wrote:
> Correctly handle a0- registers on requests from remote gdb. This fixes
>
> 'Register 1 is not available'
>
> and subsequent assertion in the remote gdb connecting to the gdbserver:
>
> 'findvar.c:291: internal-error: value_of_register_lazy:
> Assertion `frame_id_p(get_frame_id (frame))' failed.'
>
> The register structure is the same for windowed and call0 ABIs because
> currently linux kernel internally requires windowed registers, so they
> are always present.
>
> 2017-01-18 Max Filippov <jcmvbkbc@gmail.com>
> gdb/gdbserver/
Drop gdb/gdbserver/
> * linux-xtensa-low.c (C0_NREGS): New definition.
> (xtensa_fill_gregset): Call collect_register for all registers in
> a0_regnum..a0_regnum + C0_NREGS range.
> (xtensa_store_gregset): Call supply_register for all registers in
> a0_regnum..a0_regnum + C0_NREGS range.
> ---
> gdb/gdbserver/linux-xtensa-low.c | 26 ++++++++++++++++++++++++++
> 1 file changed, 26 insertions(+)
>
> diff --git a/gdb/gdbserver/linux-xtensa-low.c b/gdb/gdbserver/linux-xtensa-low.c
> index 98c0bf2..73fbfe2 100644
> --- a/gdb/gdbserver/linux-xtensa-low.c
> +++ b/gdb/gdbserver/linux-xtensa-low.c
> @@ -39,12 +39,15 @@ enum regnum {
> R_A0 = 64
> };
>
> +#define C0_NREGS 16
> +
This is duplicating code from gdb/xtensa-linux-nat. Common nat code
could be added to gdb/nat/ in an xtensa-specific file.
> static void
> xtensa_fill_gregset (struct regcache *regcache, void *buf)
> {
> elf_greg_t* rset = (elf_greg_t*)buf;
> const struct target_desc *tdesc = regcache->tdesc;
> int ar0_regnum;
> + int a0_regnum;
> char *ptr;
> int i;
>
> @@ -72,6 +75,17 @@ xtensa_fill_gregset (struct regcache *regcache, void *buf)
> collect_register_by_name (regcache, "ps", (char*)&rset[R_PS]);
> collect_register_by_name (regcache, "windowbase", (char*)&rset[R_WB]);
> collect_register_by_name (regcache, "windowstart", (char*)&rset[R_WS]);
> +
> + a0_regnum = find_regno (tdesc, "a0");
> + ptr = (char *)&rset[R_A0 + 4 * rset[R_WB]];
(char *) &rset... with space.
More occurrences of this below.
> +
> + for (i = a0_regnum; i < a0_regnum + C0_NREGS; i++)
> + {
> + if (4 * rset[R_WB] + i - a0_regnum == XCHAL_NUM_AREGS)
This looks slightly error-prone. Adding parenthesis around the
expression would look better and avoid compiler warnings.
> + ptr = (char *)&rset[R_A0];
space issue mentioned above.
> + collect_register (regcache, i, ptr);
> + ptr += register_size (tdesc, i);
> + }
> }
>
> static void
> @@ -80,6 +94,7 @@ xtensa_store_gregset (struct regcache *regcache, const void *buf)
> const elf_greg_t* rset = (const elf_greg_t*)buf;
> const struct target_desc *tdesc = regcache->tdesc;
> int ar0_regnum;
> + int a0_regnum;
> char *ptr;
> int i;
>
> @@ -94,6 +109,17 @@ xtensa_store_gregset (struct regcache *regcache, const void *buf)
> ptr += register_size (tdesc, i);
> }
>
> + a0_regnum = find_regno (tdesc, "a0");
> + ptr = (char *)&rset[R_A0 + (4 * rset[R_WB]) % XCHAL_NUM_AREGS];
> +
space issue.
> + for (i = a0_regnum; i < a0_regnum + C0_NREGS; i++)
> + {
> + if (4 * rset[R_WB] + i - a0_regnum == XCHAL_NUM_AREGS)
parenthesis around the expression.
On Mon, Feb 13, 2017 at 10:43 AM, Luis Machado
<lgustavo@codesourcery.com> wrote:
> On 01/18/2017 05:50 PM, Max Filippov wrote:
>>
>> Correctly handle a0- registers on requests from remote gdb. This fixes
>>
>> 'Register 1 is not available'
>>
>> and subsequent assertion in the remote gdb connecting to the gdbserver:
>>
>> 'findvar.c:291: internal-error: value_of_register_lazy:
>> Assertion `frame_id_p(get_frame_id (frame))' failed.'
>>
>> The register structure is the same for windowed and call0 ABIs because
>> currently linux kernel internally requires windowed registers, so they
>> are always present.
>>
>> 2017-01-18 Max Filippov <jcmvbkbc@gmail.com>
>> gdb/gdbserver/
>
>
> Drop gdb/gdbserver/
>
>> * linux-xtensa-low.c (C0_NREGS): New definition.
>> (xtensa_fill_gregset): Call collect_register for all registers in
>> a0_regnum..a0_regnum + C0_NREGS range.
>> (xtensa_store_gregset): Call supply_register for all registers in
>> a0_regnum..a0_regnum + C0_NREGS range.
>> ---
>> gdb/gdbserver/linux-xtensa-low.c | 26 ++++++++++++++++++++++++++
>> 1 file changed, 26 insertions(+)
>>
>> diff --git a/gdb/gdbserver/linux-xtensa-low.c
>> b/gdb/gdbserver/linux-xtensa-low.c
>> index 98c0bf2..73fbfe2 100644
>> --- a/gdb/gdbserver/linux-xtensa-low.c
>> +++ b/gdb/gdbserver/linux-xtensa-low.c
>> @@ -39,12 +39,15 @@ enum regnum {
>> R_A0 = 64
>> };
>>
>> +#define C0_NREGS 16
>> +
>
>
> This is duplicating code from gdb/xtensa-linux-nat. Common nat code could be
> added to gdb/nat/ in an xtensa-specific file.
Ok.
>> static void
>> xtensa_fill_gregset (struct regcache *regcache, void *buf)
>> {
>> elf_greg_t* rset = (elf_greg_t*)buf;
>> const struct target_desc *tdesc = regcache->tdesc;
>> int ar0_regnum;
>> + int a0_regnum;
>> char *ptr;
>> int i;
>>
>> @@ -72,6 +75,17 @@ xtensa_fill_gregset (struct regcache *regcache, void
>> *buf)
>> collect_register_by_name (regcache, "ps", (char*)&rset[R_PS]);
>> collect_register_by_name (regcache, "windowbase", (char*)&rset[R_WB]);
>> collect_register_by_name (regcache, "windowstart", (char*)&rset[R_WS]);
>> +
>> + a0_regnum = find_regno (tdesc, "a0");
>> + ptr = (char *)&rset[R_A0 + 4 * rset[R_WB]];
>
>
> (char *) &rset... with space.
>
> More occurrences of this below.
Will fix.
>> +
>> + for (i = a0_regnum; i < a0_regnum + C0_NREGS; i++)
>> + {
>> + if (4 * rset[R_WB] + i - a0_regnum == XCHAL_NUM_AREGS)
>
>
> This looks slightly error-prone. Adding parenthesis around the expression
> would look better and avoid compiler warnings.
Will add. It builds without warnings for me though.
>> + ptr = (char *)&rset[R_A0];
>
>
> space issue mentioned above.
Will fix.
>> + collect_register (regcache, i, ptr);
>> + ptr += register_size (tdesc, i);
>> + }
>> }
>>
>> static void
>> @@ -80,6 +94,7 @@ xtensa_store_gregset (struct regcache *regcache, const
>> void *buf)
>> const elf_greg_t* rset = (const elf_greg_t*)buf;
>> const struct target_desc *tdesc = regcache->tdesc;
>> int ar0_regnum;
>> + int a0_regnum;
>> char *ptr;
>> int i;
>>
>> @@ -94,6 +109,17 @@ xtensa_store_gregset (struct regcache *regcache, const
>> void *buf)
>> ptr += register_size (tdesc, i);
>> }
>>
>> + a0_regnum = find_regno (tdesc, "a0");
>> + ptr = (char *)&rset[R_A0 + (4 * rset[R_WB]) % XCHAL_NUM_AREGS];
>> +
>
>
> space issue.
Will fix.
>> + for (i = a0_regnum; i < a0_regnum + C0_NREGS; i++)
>> + {
>> + if (4 * rset[R_WB] + i - a0_regnum == XCHAL_NUM_AREGS)
>
>
> parenthesis around the expression.
Will add.
@@ -39,12 +39,15 @@ enum regnum {
R_A0 = 64
};
+#define C0_NREGS 16
+
static void
xtensa_fill_gregset (struct regcache *regcache, void *buf)
{
elf_greg_t* rset = (elf_greg_t*)buf;
const struct target_desc *tdesc = regcache->tdesc;
int ar0_regnum;
+ int a0_regnum;
char *ptr;
int i;
@@ -72,6 +75,17 @@ xtensa_fill_gregset (struct regcache *regcache, void *buf)
collect_register_by_name (regcache, "ps", (char*)&rset[R_PS]);
collect_register_by_name (regcache, "windowbase", (char*)&rset[R_WB]);
collect_register_by_name (regcache, "windowstart", (char*)&rset[R_WS]);
+
+ a0_regnum = find_regno (tdesc, "a0");
+ ptr = (char *)&rset[R_A0 + 4 * rset[R_WB]];
+
+ for (i = a0_regnum; i < a0_regnum + C0_NREGS; i++)
+ {
+ if (4 * rset[R_WB] + i - a0_regnum == XCHAL_NUM_AREGS)
+ ptr = (char *)&rset[R_A0];
+ collect_register (regcache, i, ptr);
+ ptr += register_size (tdesc, i);
+ }
}
static void
@@ -80,6 +94,7 @@ xtensa_store_gregset (struct regcache *regcache, const void *buf)
const elf_greg_t* rset = (const elf_greg_t*)buf;
const struct target_desc *tdesc = regcache->tdesc;
int ar0_regnum;
+ int a0_regnum;
char *ptr;
int i;
@@ -94,6 +109,17 @@ xtensa_store_gregset (struct regcache *regcache, const void *buf)
ptr += register_size (tdesc, i);
}
+ a0_regnum = find_regno (tdesc, "a0");
+ ptr = (char *)&rset[R_A0 + (4 * rset[R_WB]) % XCHAL_NUM_AREGS];
+
+ for (i = a0_regnum; i < a0_regnum + C0_NREGS; i++)
+ {
+ if (4 * rset[R_WB] + i - a0_regnum == XCHAL_NUM_AREGS)
+ ptr = (char *)&rset[R_A0];
+ supply_register (regcache, i, ptr);
+ ptr += register_size (tdesc, i);
+ }
+
/* Loop registers, if hardware has it. */
#if XCHAL_HAVE_LOOPS