This is the mail archive of the
gdb-patches@sourceware.org
mailing list for the GDB project.
Re: [PATCH 3/3] gdbserver: xtensa: add call0 support
- From: Luis Machado <lgustavo at codesourcery dot com>
- To: Max Filippov <jcmvbkbc at gmail dot com>, <gdb-patches at sourceware dot org>
- Cc: Maxim Grigoriev <maxim2405 at gmail dot com>, Woody LaRue <larue at cadence dot com>, Marc Gauthier <marc at cadence dot com>
- Date: Mon, 13 Feb 2017 12:43:30 -0600
- Subject: Re: [PATCH 3/3] gdbserver: xtensa: add call0 support
- Authentication-results: sourceware.org; auth=none
- References: <1484783438-13780-1-git-send-email-jcmvbkbc@gmail.com> <1484783438-13780-4-git-send-email-jcmvbkbc@gmail.com>
- Reply-to: Luis Machado <lgustavo at codesourcery dot com>
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.