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-rw-r--r--gdb/ppc-linux-nat.c405
1 files changed, 400 insertions, 5 deletions
diff --git a/gdb/ppc-linux-nat.c b/gdb/ppc-linux-nat.c
index 0567e28..4d8f503 100644
--- a/gdb/ppc-linux-nat.c
+++ b/gdb/ppc-linux-nat.c
@@ -70,6 +70,16 @@
#define PTRACE_SETVRREGS 19
#endif
+
+/* Similarly for the ptrace requests for getting / setting the SPE
+ registers (ev0 -- ev31, acc, and spefscr). See the description of
+ gdb_evrregset_t for details. */
+#ifndef PTRACE_GETEVRREGS
+#define PTRACE_GETEVRREGS 20
+#define PTRACE_SETEVRREGS 21
+#endif
+
+
/* This oddity is because the Linux kernel defines elf_vrregset_t as
an array of 33 16 bytes long elements. I.e. it leaves out vrsave.
However the PTRACE_GETVRREGS and PTRACE_SETVRREGS requests return
@@ -101,9 +111,49 @@
typedef char gdb_vrregset_t[SIZEOF_VRREGS];
-/* For runtime check of ptrace support for VRREGS. */
+
+/* On PPC processors that support the the Signal Processing Extension
+ (SPE) APU, the general-purpose registers are 64 bits long.
+ However, the ordinary Linux PTRACE_PEEKUSR / PTRACE_POKEUSR /
+ PT_READ_U / PT_WRITE_U ptrace calls only access the lower half of
+ each register, to allow them to behave the same way they do on
+ non-SPE systems. There's a separate pair of calls,
+ PTRACE_GETEVRREGS / PTRACE_SETEVRREGS, that read and write the top
+ halves of all the general-purpose registers at once, along with
+ some SPE-specific registers.
+
+ GDB itself continues to claim the general-purpose registers are 32
+ bits long; the full 64-bit registers are called 'ev0' -- 'ev31'.
+ The ev registers are raw registers, and the GPR's are pseudo-
+ registers mapped onto their lower halves. This means that reading
+ and writing ev registers involves a mix of regset-at-once
+ PTRACE_{GET,SET}EVRREGS calls and register-at-a-time
+ PTRACE_{PEEK,POKE}USR calls.
+
+ This is the structure filled in by PTRACE_GETEVRREGS and written to
+ the inferior's registers by PTRACE_SETEVRREGS. */
+struct gdb_evrregset_t
+{
+ unsigned long evr[32];
+ unsigned long long acc;
+ unsigned long spefscr;
+};
+
+
+/* Non-zero if our kernel may support the PTRACE_GETVRREGS and
+ PTRACE_SETVRREGS requests, for reading and writing the Altivec
+ registers. Zero if we've tried one of them and gotten an
+ error. */
int have_ptrace_getvrregs = 1;
+
+/* Non-zero if our kernel may support the PTRACE_GETEVRREGS and
+ PTRACE_SETEVRREGS requests, for reading and writing the SPE
+ registers. Zero if we've tried one of them and gotten an
+ error. */
+int have_ptrace_getsetevrregs = 1;
+
+
int
kernel_u_size (void)
{
@@ -203,6 +253,137 @@ fetch_altivec_register (int tid, int regno)
regs + (regno - tdep->ppc_vr0_regnum) * vrregsize + offset);
}
+/* Fetch the top 32 bits of TID's general-purpose registers and the
+ SPE-specific registers, and place the results in EVRREGSET. If we
+ don't support PTRACE_GETEVRREGS, then just fill EVRREGSET with
+ zeros.
+
+ All the logic to deal with whether or not the PTRACE_GETEVRREGS and
+ PTRACE_SETEVRREGS requests are supported is isolated here, and in
+ set_spe_registers. */
+static void
+get_spe_registers (int tid, struct gdb_evrregset_t *evrregset)
+{
+ if (have_ptrace_getsetevrregs)
+ {
+ if (ptrace (PTRACE_GETEVRREGS, tid, 0, evrregset) >= 0)
+ return;
+ else
+ {
+ /* EIO means that the PTRACE_GETEVRREGS request isn't supported;
+ we just return zeros. */
+ if (errno == EIO)
+ have_ptrace_getsetevrregs = 0;
+ else
+ /* Anything else needs to be reported. */
+ perror_with_name ("Unable to fetch SPE registers");
+ }
+ }
+
+ memset (evrregset, 0, sizeof (*evrregset));
+}
+
+/* Assuming TID refers to an SPE process, store the full 64-bit value
+ of TID's ev register EV_REGNUM in DEST, getting the high bits from
+ EVRREGS and the low bits from the kernel via ptrace. */
+static void
+read_spliced_spe_reg (int tid, int ev_regnum,
+ struct gdb_evrregset_t *evrregs,
+ char *dest)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+
+ /* Make sure we're trying to read an EV register; that's all we
+ handle. */
+ gdb_assert (tdep->ppc_ev0_regnum <= ev_regnum
+ && ev_regnum <= tdep->ppc_ev31_regnum);
+
+ /* Make sure the sizes for the splicing add up. */
+ gdb_assert (sizeof (evrregs->evr[0]) + sizeof (PTRACE_XFER_TYPE)
+ == register_size (current_gdbarch, ev_regnum));
+
+ {
+ /* The index of ev_regnum in evrregs->evr[]. */
+ int ev_index = ev_regnum - tdep->ppc_ev0_regnum;
+
+ /* The number of the corresponding general-purpose register, which
+ holds the lower 32 bits of the EV register. */
+ int gpr_regnum = tdep->ppc_gp0_regnum + ev_index;
+
+ /* The offset of gpr_regnum in the process's uarea. */
+ CORE_ADDR gpr_uoffset = ppc_register_u_addr (gpr_regnum);
+
+ /* The low word of the EV register's value. */
+ PTRACE_XFER_TYPE low_word;
+
+ /* The PTRACE_PEEKUSR / PT_READ_U ptrace requests need to be able
+ to return arbitrary register values, so they can't return -1 to
+ indicate an error. So we clear errno, and then check it after
+ the call. */
+ errno = 0;
+ low_word = ptrace (PT_READ_U, tid, (PTRACE_ARG3_TYPE) gpr_uoffset, 0);
+
+ if (errno != 0)
+ {
+ char message[128];
+ sprintf (message, "reading register %s (#%d)",
+ REGISTER_NAME (ev_regnum), ev_regnum);
+ perror_with_name (message);
+ }
+
+ if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
+ {
+ memcpy (dest, &evrregs->evr[ev_index],
+ sizeof (evrregs->evr[ev_index]));
+ * (PTRACE_XFER_TYPE *) (dest + sizeof (evrregs->evr[ev_index]))
+ = low_word;
+ }
+ else if (TARGET_BYTE_ORDER == BFD_ENDIAN_LITTLE)
+ {
+ * (PTRACE_XFER_TYPE *) dest = low_word;
+ memcpy (dest + sizeof (PTRACE_XFER_TYPE),
+ &evrregs->evr[ev_index], sizeof (evrregs->evr[ev_index]));
+ }
+ else
+ gdb_assert (0);
+ }
+}
+
+
+/* On SPE machines, supply the full value of the SPE register REGNO
+ from TID. This handles ev0 -- ev31 and acc, which are 64 bits
+ long, and spefscr, which is 32 bits long. */
+static void
+fetch_spe_register (int tid, int regno)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+ struct gdb_evrregset_t evrregs;
+
+ get_spe_registers (tid, &evrregs);
+
+ if (tdep->ppc_ev0_regnum <= regno
+ && regno <= tdep->ppc_ev31_regnum)
+ {
+ char buf[MAX_REGISTER_SIZE];
+ read_spliced_spe_reg (tid, regno, &evrregs, buf);
+ supply_register (regno, buf);
+ }
+ else if (regno == tdep->ppc_acc_regnum)
+ {
+ gdb_assert (sizeof (evrregs.acc)
+ == register_size (current_gdbarch, regno));
+ supply_register (regno, &evrregs.acc);
+ }
+ else if (regno == tdep->ppc_spefscr_regnum)
+ {
+ gdb_assert (sizeof (evrregs.spefscr)
+ == register_size (current_gdbarch, regno));
+ supply_register (regno, &evrregs.spefscr);
+ }
+ else
+ gdb_assert (0);
+}
+
static void
fetch_register (int tid, int regno)
{
@@ -213,6 +394,12 @@ fetch_register (int tid, int regno)
unsigned int offset; /* Offset of registers within the u area. */
char buf[MAX_REGISTER_SIZE];
+ /* Sanity check: this function should only be called to fetch raw
+ registers' values, never pseudoregisters' values. */
+ if (tdep->ppc_gp0_regnum <= regno
+ && regno < tdep->ppc_gp0_regnum + ppc_num_gprs)
+ gdb_assert (! tdep->ppc_gprs_pseudo_p);
+
if (altivec_register_p (regno))
{
/* If this is the first time through, or if it is not the first
@@ -228,6 +415,11 @@ fetch_register (int tid, int regno)
AltiVec registers, fall through and return zeroes, because
regaddr will be -1 in this case. */
}
+ else if (spe_register_p (regno))
+ {
+ fetch_spe_register (tid, regno);
+ return;
+ }
if (regaddr == -1)
{
@@ -319,14 +511,41 @@ fetch_altivec_registers (int tid)
supply_vrregset (&regs);
}
+/* On SPE machines, fetch the full 64 bits of all the general-purpose
+ registers, as well as the SPE-specific registers 'acc' and
+ 'spefscr'. */
+static void
+fetch_spe_registers (int tid)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+ struct gdb_evrregset_t evrregs;
+ int i;
+
+ get_spe_registers (tid, &evrregs);
+
+ /* Splice and supply each of the EV registers. */
+ for (i = 0; i < ppc_num_gprs; i++)
+ {
+ char buf[MAX_REGISTER_SIZE];
+
+ read_spliced_spe_reg (tid, tdep->ppc_ev0_regnum + i, &evrregs, buf);
+ supply_register (tdep->ppc_ev0_regnum + i, buf);
+ }
+
+ /* Supply the SPE-specific registers. */
+ supply_register (tdep->ppc_acc_regnum, &evrregs.acc);
+ supply_register (tdep->ppc_spefscr_regnum, &evrregs.spefscr);
+}
+
static void
fetch_ppc_registers (int tid)
{
int i;
struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
- for (i = 0; i < ppc_num_gprs; i++)
- fetch_register (tid, tdep->ppc_gp0_regnum + i);
+ if (! tdep->ppc_gprs_pseudo_p)
+ for (i = 0; i < ppc_num_gprs; i++)
+ fetch_register (tid, tdep->ppc_gp0_regnum + i);
if (tdep->ppc_fp0_regnum >= 0)
for (i = 0; i < ppc_num_fprs; i++)
fetch_register (tid, tdep->ppc_fp0_regnum + i);
@@ -348,6 +567,8 @@ fetch_ppc_registers (int tid)
if (have_ptrace_getvrregs)
if (tdep->ppc_vr0_regnum != -1 && tdep->ppc_vrsave_regnum != -1)
fetch_altivec_registers (tid);
+ if (tdep->ppc_ev0_regnum >= 0)
+ fetch_spe_registers (tid);
}
/* Fetch registers from the child process. Fetch all registers if
@@ -403,6 +624,136 @@ store_altivec_register (int tid, int regno)
perror_with_name ("Unable to store AltiVec register");
}
+/* Assuming TID referrs to an SPE process, set the top halves of TID's
+ general-purpose registers and its SPE-specific registers to the
+ values in EVRREGSET. If we don't support PTRACE_SETEVRREGS, do
+ nothing.
+
+ All the logic to deal with whether or not the PTRACE_GETEVRREGS and
+ PTRACE_SETEVRREGS requests are supported is isolated here, and in
+ get_spe_registers. */
+static void
+set_spe_registers (int tid, struct gdb_evrregset_t *evrregset)
+{
+ if (have_ptrace_getsetevrregs)
+ {
+ if (ptrace (PTRACE_SETEVRREGS, tid, 0, evrregset) >= 0)
+ return;
+ else
+ {
+ /* EIO means that the PTRACE_SETEVRREGS request isn't
+ supported; we fail silently, and don't try the call
+ again. */
+ if (errno == EIO)
+ have_ptrace_getsetevrregs = 0;
+ else
+ /* Anything else needs to be reported. */
+ perror_with_name ("Unable to set SPE registers");
+ }
+ }
+}
+
+/* Store the bytes at SRC as the contents of TID's EV register EV_REGNUM.
+ Write the less significant word to TID using ptrace, and copy the
+ more significant word to the appropriate slot in EVRREGS. */
+static void
+write_spliced_spe_reg (int tid, int ev_regnum,
+ struct gdb_evrregset_t *evrregs,
+ char *src)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+
+ /* Make sure we're trying to write an EV register; that's all we
+ handle. */
+ gdb_assert (tdep->ppc_ev0_regnum <= ev_regnum
+ && ev_regnum <= tdep->ppc_ev31_regnum);
+
+ /* Make sure the sizes for the splicing add up. */
+ gdb_assert (sizeof (evrregs->evr[0]) + sizeof (PTRACE_XFER_TYPE)
+ == register_size (current_gdbarch, ev_regnum));
+
+ {
+ int ev_index = ev_regnum - tdep->ppc_ev0_regnum;
+
+ /* The number of the corresponding general-purpose register, which
+ holds the lower 32 bits of the EV register. */
+ int gpr_regnum = tdep->ppc_gp0_regnum + ev_index;
+
+ /* The offset of gpr_regnum in the process's uarea. */
+ CORE_ADDR gpr_uoffset = ppc_register_u_addr (gpr_regnum);
+
+ /* The PTRACE_POKEUSR / PT_WRITE_U ptrace requests need to be able
+ to return arbitrary register values, so they can't return -1 to
+ indicate an error. So we clear errno, and check it again
+ afterwards. */
+ errno = 0;
+
+ if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
+ {
+ memcpy (&evrregs->evr[ev_index], src, sizeof (evrregs->evr[ev_index]));
+ ptrace (PT_WRITE_U, tid, (PTRACE_ARG3_TYPE) gpr_uoffset,
+ * (PTRACE_XFER_TYPE *) (src + sizeof (evrregs->evr[0])));
+ }
+ else if (TARGET_BYTE_ORDER == BFD_ENDIAN_LITTLE)
+ {
+ ptrace (PT_WRITE_U, tid, (PTRACE_ARG3_TYPE) gpr_uoffset,
+ * (PTRACE_XFER_TYPE *) src);
+ memcpy (&evrregs->evr[ev_index], src + sizeof (PTRACE_XFER_TYPE),
+ sizeof (evrregs->evr[ev_index]));
+ }
+ else
+ gdb_assert (0);
+
+ if (errno != 0)
+ {
+ char message[128];
+ sprintf (message, "writing register %s (#%d)",
+ REGISTER_NAME (ev_regnum), ev_regnum);
+ perror_with_name (message);
+ }
+ }
+}
+
+/* Write GDB's value for the SPE register REGNO to TID. */
+static void
+store_spe_register (int tid, int regno)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+ struct gdb_evrregset_t evrregs;
+
+ /* We can only read and write the entire EVR register set at a time,
+ so to write just a single register, we do a read-modify-write
+ maneuver. */
+ get_spe_registers (tid, &evrregs);
+
+ if (tdep->ppc_ev0_regnum >= 0
+ && tdep->ppc_ev0_regnum <= regno && regno <= tdep->ppc_ev31_regnum)
+ {
+ char buf[MAX_REGISTER_SIZE];
+ regcache_collect (regno, buf);
+ write_spliced_spe_reg (tid, regno, &evrregs, buf);
+ }
+ else if (tdep->ppc_acc_regnum >= 0
+ && regno == tdep->ppc_acc_regnum)
+ {
+ gdb_assert (sizeof (evrregs.acc)
+ == register_size (current_gdbarch, regno));
+ regcache_collect (regno, &evrregs.acc);
+ }
+ else if (tdep->ppc_spefscr_regnum >= 0
+ && regno == tdep->ppc_spefscr_regnum)
+ {
+ gdb_assert (sizeof (evrregs.spefscr)
+ == register_size (current_gdbarch, regno));
+ regcache_collect (regno, &evrregs.spefscr);
+ }
+ else
+ gdb_assert (0);
+
+ /* Write back the modified register set. */
+ set_spe_registers (tid, &evrregs);
+}
+
static void
store_register (int tid, int regno)
{
@@ -413,11 +764,22 @@ store_register (int tid, int regno)
size_t bytes_to_transfer;
char buf[MAX_REGISTER_SIZE];
+ /* Sanity check: this function should only be called to store raw
+ registers' values, never pseudoregisters' values. */
+ if (tdep->ppc_gp0_regnum <= regno
+ && regno < tdep->ppc_gp0_regnum + ppc_num_gprs)
+ gdb_assert (! tdep->ppc_gprs_pseudo_p);
+
if (altivec_register_p (regno))
{
store_altivec_register (tid, regno);
return;
}
+ else if (spe_register_p (regno))
+ {
+ store_spe_register (tid, regno);
+ return;
+ }
if (regaddr == -1)
return;
@@ -510,13 +872,44 @@ store_altivec_registers (int tid)
}
static void
+store_spe_registers (tid)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+ struct gdb_evrregset_t evrregs;
+ int i;
+
+ /* The code below should store to every field of evrregs; if that
+ doesn't happen, make it obvious by initializing it with
+ suspicious values. */
+ memset (&evrregs, 42, sizeof (evrregs));
+
+ for (i = 0; i < ppc_num_gprs; i++)
+ {
+ char buf[MAX_REGISTER_SIZE];
+
+ regcache_collect (tdep->ppc_ev0_regnum + i, buf);
+ write_spliced_spe_reg (tid, tdep->ppc_ev0_regnum + i, &evrregs, buf);
+ }
+
+ gdb_assert (sizeof (evrregs.acc)
+ == register_size (current_gdbarch, tdep->ppc_acc_regnum));
+ regcache_collect (tdep->ppc_acc_regnum, &evrregs.acc);
+ gdb_assert (sizeof (evrregs.spefscr)
+ == register_size (current_gdbarch, tdep->ppc_spefscr_regnum));
+ regcache_collect (tdep->ppc_acc_regnum, &evrregs.spefscr);
+
+ set_spe_registers (tid, &evrregs);
+}
+
+static void
store_ppc_registers (int tid)
{
int i;
struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
- for (i = 0; i < ppc_num_gprs; i++)
- store_register (tid, tdep->ppc_gp0_regnum + i);
+ if (! tdep->ppc_gprs_pseudo_p)
+ for (i = 0; i < ppc_num_gprs; i++)
+ store_register (tid, tdep->ppc_gp0_regnum + i);
if (tdep->ppc_fp0_regnum >= 0)
for (i = 0; i < ppc_num_fprs; i++)
store_register (tid, tdep->ppc_fp0_regnum + i);
@@ -538,6 +931,8 @@ store_ppc_registers (int tid)
if (have_ptrace_getvrregs)
if (tdep->ppc_vr0_regnum != -1 && tdep->ppc_vrsave_regnum != -1)
store_altivec_registers (tid);
+ if (tdep->ppc_ev0_regnum >= 0)
+ store_spe_registers (tid);
}
void