[PATCH 23/24] gdb: migrate arm to new gdbarch_pseudo_register_write

Simon Marchi
2023-11-08T05:21:59Z

From: Simon Marchi <simon.marchi@efficios.com>

Make arm use the new gdbarch_pseudo_register_write. This fixes writing
pseudo registers to non-current frames for that architecture.

Change-Id: Icb2a649ab6394817844230e9e94c3d0564d2f765
---
gdb/arm-tdep.c | 62 +++++++++++++++++++++++++++++---------------------
1 file changed, 36 insertions(+), 26 deletions(-)

diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
index 9bf51485b800..a0d019b564bf 100644
--- a/gdb/arm-tdep.c
+++ b/gdb/arm-tdep.c
@@ -9908,57 +9908,67 @@ arm_neon_quad_write (struct gdbarch *gdbarch, struct regcache *regcache,
regcache->raw_write (double_regnum + 1, buf + 8);
}

+static void
+arm_neon_quad_write (gdbarch *gdbarch, frame_info_ptr next_frame,
+ int quad_reg_index, gdb::array_view<const gdb_byte> buf)
+{
+ std::string raw_reg_name = string_printf ("d%d", quad_reg_index << 1);
+ int double_regnum
+ = user_reg_map_name_to_regnum (gdbarch, raw_reg_name.data (),
+ raw_reg_name.length ());
+
+ pseudo_to_concat_raw (next_frame, buf, double_regnum, double_regnum + 1);
+}
+
/* Store the contents of BUF to the MVE pseudo register REGNUM. */

static void
-arm_mve_pseudo_write (struct gdbarch *gdbarch, struct regcache *regcache,
- int regnum, const gdb_byte *buf)
+arm_mve_pseudo_write (gdbarch *gdbarch, frame_info_ptr next_frame,
+ int pseudo_reg_num, gdb::array_view<const gdb_byte> buf)
{
arm_gdbarch_tdep *tdep = gdbarch_tdep<arm_gdbarch_tdep> (gdbarch);

/* P0 is the first 16 bits of VPR. */
- regcache->raw_write_part (tdep->mve_vpr_regnum, 0, 2, buf);
+ pseudo_to_raw_part(next_frame, buf, tdep->mve_vpr_regnum, 0);
}

static void
-arm_pseudo_write (struct gdbarch *gdbarch, struct regcache *regcache,
- int regnum, const gdb_byte *buf)
+arm_pseudo_write (gdbarch *gdbarch, frame_info_ptr next_frame,
+ const int pseudo_reg_num,
+ gdb::array_view<const gdb_byte> buf)
{
- const int num_regs = gdbarch_num_regs (gdbarch);
- char name_buf[4];
- gdb_byte reg_buf[8];
- int offset, double_regnum;
arm_gdbarch_tdep *tdep = gdbarch_tdep<arm_gdbarch_tdep> (gdbarch);

- gdb_assert (regnum >= num_regs);
+ gdb_assert (pseudo_reg_num >= gdbarch_num_regs (gdbarch));

- if (is_q_pseudo (gdbarch, regnum))
+ if (is_q_pseudo (gdbarch, pseudo_reg_num))
{
/* Quad-precision register. */
- arm_neon_quad_write (gdbarch, regcache,
- regnum - tdep->q_pseudo_base, buf);
+ arm_neon_quad_write (gdbarch, next_frame,
+ pseudo_reg_num - tdep->q_pseudo_base, buf);
}
- else if (is_mve_pseudo (gdbarch, regnum))
- arm_mve_pseudo_write (gdbarch, regcache, regnum, buf);
+ else if (is_mve_pseudo (gdbarch, pseudo_reg_num))
+ arm_mve_pseudo_write (gdbarch, next_frame, pseudo_reg_num, buf);
else
{
- regnum -= tdep->s_pseudo_base;
+ int s_reg_index = pseudo_reg_num - tdep->s_pseudo_base;
+
/* Single-precision register. */
- gdb_assert (regnum < 32);
+ gdb_assert (s_reg_index < 32);

/* s0 is always the least significant half of d0. */
+ int offset;
if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
- offset = (regnum & 1) ? 0 : 4;
+ offset = (s_reg_index & 1) ? 0 : 4;
else
- offset = (regnum & 1) ? 4 : 0;
+ offset = (s_reg_index & 1) ? 4 : 0;

- xsnprintf (name_buf, sizeof (name_buf), "d%d", regnum >> 1);
- double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
- strlen (name_buf));
+ std::string raw_reg_name = string_printf ("d%d", s_reg_index >> 1);
+ int double_regnum
+ = user_reg_map_name_to_regnum (gdbarch, raw_reg_name.c_str (),
+ raw_reg_name.length ());

- regcache->raw_read (double_regnum, reg_buf);
- memcpy (reg_buf + offset, buf, 4);
- regcache->raw_write (double_regnum, reg_buf);
+ pseudo_to_raw_part (next_frame, buf, double_regnum, offset);
}
}

@@ -10918,7 +10928,7 @@ arm_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
{
set_gdbarch_num_pseudo_regs (gdbarch, num_pseudos);
set_gdbarch_pseudo_register_read_value (gdbarch, arm_pseudo_read_value);
- set_gdbarch_deprecated_pseudo_register_write (gdbarch, arm_pseudo_write);
+ set_gdbarch_pseudo_register_write (gdbarch, arm_pseudo_write);
}

/* Add standard register aliases. We add aliases even for those
--
2.42.1