/* Native-dependent code for Linux running on i386's, for GDB.
+ Copyright (C) 1999, 2000 Free Software Foundation, Inc.
-This file is part of GDB.
+ This file is part of GDB.
-This program is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2 of the License, or
-(at your option) any later version.
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU General Public License for more details.
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
-You should have received a copy of the GNU General Public License
-along with this program; if not, write to the Free Software
-Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
#include "defs.h"
#include "inferior.h"
#include "gdbcore.h"
-/* For i386_linux_skip_solib_resolver */
+/* For i386_linux_skip_solib_resolver. */
#include "symtab.h"
-#include "frame.h"
#include "symfile.h"
#include "objfiles.h"
#include <sys/reg.h>
#endif
-/* This is a duplicate of the table in i386-xdep.c. */
+/* On Linux, threads are implemented as pseudo-processes, in which
+ case we may be tracing more than one process at a time. In that
+ case, inferior_pid will contain the main process ID and the
+ individual thread (process) ID mashed together. These macros are
+ used to separate them out. These definitions should be overridden
+ if thread support is included. */
+#if !defined (PIDGET) /* Default definition for PIDGET/TIDGET. */
+#define PIDGET(PID) PID
+#define TIDGET(PID) 0
+#endif
+
+
+/* The register sets used in Linux ELF core-dumps are identical to the
+ register sets in `struct user' that is used for a.out core-dumps,
+ and is also used by `ptrace'. The corresponding types are
+ `elf_gregset_t' for the general-purpose registers (with
+ `elf_greg_t' the type of a single GP register) and `elf_fpregset_t'
+ for the floating-point registers.
+
+ Those types used to be available under the names `gregset_t' and
+ `fpregset_t' too, and this file used those names in the past. But
+ those names are now used for the register sets used in the
+ `mcontext_t' type, and have a different size and layout. */
+
+/* Mapping between the general-purpose registers in `struct user'
+ format and GDB's register array layout. */
static int regmap[] =
{
EAX, ECX, EDX, EBX,
UESP, EBP, ESI, EDI,
EIP, EFL, CS, SS,
- DS, ES, FS, GS,
+ DS, ES, FS, GS
};
+/* Which ptrace request retrieves which registers?
+ These apply to the corresponding SET requests as well. */
+#define GETREGS_SUPPLIES(regno) \
+ (0 <= (regno) && (regno) <= 15)
+#define GETFPREGS_SUPPLIES(regno) \
+ (FP0_REGNUM <= (regno) && (regno) <= LAST_FPU_CTRL_REGNUM)
+#define GETXFPREGS_SUPPLIES(regno) \
+ (FP0_REGNUM <= (regno) && (regno) <= MXCSR_REGNUM)
+
+/* Does the current host support the GETREGS request? */
+int have_ptrace_getregs =
+#ifdef HAVE_PTRACE_GETREGS
+ 1
+#else
+ 0
+#endif
+;
+
+/* Does the current host support the GETXFPREGS request? The header
+ file may or may not define it, and even if it is defined, the
+ kernel will return EIO if it's running on a pre-SSE processor.
+
+ PTRACE_GETXFPREGS is a Cygnus invention, since we wrote our own
+ Linux kernel patch for SSE support. That patch may or may not
+ actually make it into the official distribution. If you find that
+ years have gone by since this stuff was added, and Linux isn't
+ using PTRACE_GETXFPREGS, that means that our patch didn't make it,
+ and you can delete this, and the related code.
+
+ My instinct is to attach this to some architecture- or
+ target-specific data structure, but really, a particular GDB
+ process can only run on top of one kernel at a time. So it's okay
+ for this to be a simple variable. */
+int have_ptrace_getxfpregs =
+#ifdef HAVE_PTRACE_GETXFPREGS
+ 1
+#else
+ 0
+#endif
+;
+
+\f
+/* Fetching registers directly from the U area, one at a time. */
+
+/* FIXME: kettenis/2000-03-05: This duplicates code from `inptrace.c'.
+ The problem is that we define FETCH_INFERIOR_REGISTERS since we
+ want to use our own versions of {fetch,store}_inferior_registers
+ that use the GETREGS request. This means that the code in
+ `infptrace.c' is #ifdef'd out. But we need to fall back on that
+ code when GDB is running on top of a kernel that doesn't support
+ the GETREGS request. I want to avoid changing `infptrace.c' right
+ now. */
+
+/* Default the type of the ptrace transfer to int. */
+#ifndef PTRACE_XFER_TYPE
+#define PTRACE_XFER_TYPE int
+#endif
+
+/* Registers we shouldn't try to fetch. */
+#if !defined (CANNOT_FETCH_REGISTER)
+#define CANNOT_FETCH_REGISTER(regno) 0
+#endif
+
+/* Fetch one register. */
+
+static void
+fetch_register (regno)
+ int regno;
+{
+ /* This isn't really an address. But ptrace thinks of it as one. */
+ CORE_ADDR regaddr;
+ char mess[128]; /* For messages */
+ register int i;
+ unsigned int offset; /* Offset of registers within the u area. */
+ char buf[MAX_REGISTER_RAW_SIZE];
+ int tid;
+
+ if (CANNOT_FETCH_REGISTER (regno))
+ {
+ memset (buf, '\0', REGISTER_RAW_SIZE (regno)); /* Supply zeroes */
+ supply_register (regno, buf);
+ return;
+ }
+
+ /* Overload thread id onto process id */
+ if ((tid = TIDGET (inferior_pid)) == 0)
+ tid = inferior_pid; /* no thread id, just use process id */
+
+ offset = U_REGS_OFFSET;
+
+ regaddr = register_addr (regno, offset);
+ for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (PTRACE_XFER_TYPE))
+ {
+ errno = 0;
+ *(PTRACE_XFER_TYPE *) & buf[i] = ptrace (PT_READ_U, tid,
+ (PTRACE_ARG3_TYPE) regaddr, 0);
+ regaddr += sizeof (PTRACE_XFER_TYPE);
+ if (errno != 0)
+ {
+ sprintf (mess, "reading register %s (#%d)",
+ REGISTER_NAME (regno), regno);
+ perror_with_name (mess);
+ }
+ }
+ supply_register (regno, buf);
+}
+
+/* Fetch register values from the inferior.
+ If REGNO is negative, do this for all registers.
+ Otherwise, REGNO specifies which register (so we can save time). */
-/* Given a pointer to a general register set in struct user format
- (gregset_t *), unpack the register contents and supply them as
- gdb's idea of the current register values. */
void
-supply_gregset (gregsetp)
- gregset_t *gregsetp;
+old_fetch_inferior_registers (regno)
+ int regno;
{
- register int regi;
- register greg_t *regp = (greg_t *) gregsetp;
+ if (regno >= 0)
+ {
+ fetch_register (regno);
+ }
+ else
+ {
+ for (regno = 0; regno < ARCH_NUM_REGS; regno++)
+ {
+ fetch_register (regno);
+ }
+ }
+}
- for (regi = 0; regi < NUM_GREGS; regi++)
+/* Registers we shouldn't try to store. */
+#if !defined (CANNOT_STORE_REGISTER)
+#define CANNOT_STORE_REGISTER(regno) 0
+#endif
+
+/* Store one register. */
+
+static void
+store_register (regno)
+ int regno;
+{
+ /* This isn't really an address. But ptrace thinks of it as one. */
+ CORE_ADDR regaddr;
+ char mess[128]; /* For messages */
+ register int i;
+ unsigned int offset; /* Offset of registers within the u area. */
+ int tid;
+
+ if (CANNOT_STORE_REGISTER (regno))
+ {
+ return;
+ }
+
+ /* Overload thread id onto process id */
+ if ((tid = TIDGET (inferior_pid)) == 0)
+ tid = inferior_pid; /* no thread id, just use process id */
+
+ offset = U_REGS_OFFSET;
+
+ regaddr = register_addr (regno, offset);
+ for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (PTRACE_XFER_TYPE))
{
- supply_register (regi, (char *) (regp + regmap[regi]));
+ errno = 0;
+ ptrace (PT_WRITE_U, tid, (PTRACE_ARG3_TYPE) regaddr,
+ *(PTRACE_XFER_TYPE *) & registers[REGISTER_BYTE (regno) + i]);
+ regaddr += sizeof (PTRACE_XFER_TYPE);
+ if (errno != 0)
+ {
+ sprintf (mess, "writing register %s (#%d)",
+ REGISTER_NAME (regno), regno);
+ perror_with_name (mess);
+ }
}
}
-/* Fill in a gregset_t object with selected data from a gdb-format
- register file.
- - GREGSETP points to the gregset_t object to be filled.
- - GDB_REGS points to the GDB-style register file providing the data.
- - VALID is an array indicating which registers in GDB_REGS are
- valid; the parts of *GREGSETP that would hold registers marked
- invalid in GDB_REGS are left unchanged. If VALID is zero, all
- registers are assumed to be valid. */
+/* Store our register values back into the inferior.
+ If REGNO is negative, do this for all registers.
+ Otherwise, REGNO specifies which register (so we can save time). */
+
void
-convert_to_gregset (gregset_t *gregsetp,
- char *gdb_regs,
- signed char *valid)
+old_store_inferior_registers (regno)
+ int regno;
{
+ if (regno >= 0)
+ {
+ store_register (regno);
+ }
+ else
+ {
+ for (regno = 0; regno < ARCH_NUM_REGS; regno++)
+ {
+ store_register (regno);
+ }
+ }
+}
+
+\f
+/* Transfering the general-purpose registers between GDB, inferiors
+ and core files. */
+
+/* Fill GDB's register array with the genereal-purpose register values
+ in *GREGSETP. */
+
+void
+supply_gregset (elf_gregset_t *gregsetp)
+{
+ elf_greg_t *regp = (elf_greg_t *) gregsetp;
+ int regi;
+
+ for (regi = 0; regi < NUM_GREGS; regi++)
+ supply_register (regi, (char *) (regp + regmap[regi]));
+}
+
+/* Convert the valid general-purpose register values in GDB's register
+ array to `struct user' format and store them in *GREGSETP. The
+ array VALID indicates which register values are valid. If VALID is
+ NULL, all registers are assumed to be valid. */
+
+static void
+convert_to_gregset (elf_gregset_t *gregsetp, signed char *valid)
+{
+ elf_greg_t *regp = (elf_greg_t *) gregsetp;
int regi;
- register greg_t *regp = (greg_t *) gregsetp;
for (regi = 0; regi < NUM_GREGS; regi++)
if (! valid || valid[regi])
*(regp + regmap[regi]) = * (int *) ®isters[REGISTER_BYTE (regi)];
}
+/* Fill register REGNO (if it is a general-purpose register) in
+ *GREGSETPS with the value in GDB's register array. If REGNO is -1,
+ do this for all registers. */
void
-fill_gregset (gregset_t *gregsetp,
- int regno)
+fill_gregset (elf_gregset_t *gregsetp, int regno)
{
if (regno == -1)
- convert_to_gregset (gregsetp, registers, 0);
- else
+ {
+ convert_to_gregset (gregsetp, NULL);
+ return;
+ }
+
+ if (GETREGS_SUPPLIES (regno))
{
signed char valid[NUM_GREGS];
+
memset (valid, 0, sizeof (valid));
valid[regno] = 1;
- convert_to_gregset (gregsetp, valid, valid);
+
+ convert_to_gregset (gregsetp, valid);
+ }
+}
+
+#ifdef HAVE_PTRACE_GETREGS
+
+/* Fetch all general-purpose registers from process/thread TID and
+ store their values in GDB's register array. */
+
+static void
+fetch_regs (int tid)
+{
+ elf_gregset_t regs;
+ int ret;
+
+ ret = ptrace (PTRACE_GETREGS, tid, 0, (int) ®s);
+ if (ret < 0)
+ {
+ if (errno == EIO)
+ {
+ /* The kernel we're running on doesn't support the GETREGS
+ request. Reset `have_ptrace_getregs'. */
+ have_ptrace_getregs = 0;
+ return;
+ }
+
+ warning ("Couldn't get registers.");
+ return;
}
+
+ supply_gregset (®s);
}
+/* Store all valid general-purpose registers in GDB's register array
+ into the process/thread specified by TID. */
+
+static void
+store_regs (int tid)
+{
+ elf_gregset_t regs;
+ int ret;
+
+ ret = ptrace (PTRACE_GETREGS, tid, 0, (int) ®s);
+ if (ret < 0)
+ {
+ warning ("Couldn't get registers.");
+ return;
+ }
+
+ convert_to_gregset (®s, register_valid);
+
+ ret = ptrace (PTRACE_SETREGS, tid, 0, (int) ®s);
+ if (ret < 0)
+ {
+ warning ("Couldn't write registers.");
+ return;
+ }
+}
+
+#else
+
+static void fetch_regs (int tid) {}
+static void store_regs (int tid) {}
+
+#endif
+
+\f
+/* Transfering floating-point registers between GDB, inferiors and cores. */
-/* Where does st(N) start in the fpregset_t structure F? */
-#define FPREGSET_T_FPREG_OFFSET(f, n) \
- ((char *) &(f)->st_space + (n) * 10)
+/* What is the address of st(N) within the floating-point register set F? */
+#define FPREG_ADDR(f, n) ((char *) &(f)->st_space + (n) * 10)
-/* Fill GDB's register file with the floating-point register values in
+/* Fill GDB's register array with the floating-point register values in
*FPREGSETP. */
+
void
-supply_fpregset (fpregset_t *fpregsetp)
+supply_fpregset (elf_fpregset_t *fpregsetp)
{
- int i;
+ int reg;
+ long l;
/* Supply the floating-point registers. */
- for (i = 0; i < 8; i++)
- supply_register (FP0_REGNUM + i, FPREGSET_T_FPREG_OFFSET (fpregsetp, i));
-
- supply_register (FCTRL_REGNUM, (char *) &fpregsetp->cwd);
- supply_register (FSTAT_REGNUM, (char *) &fpregsetp->swd);
- supply_register (FTAG_REGNUM, (char *) &fpregsetp->twd);
+ for (reg = 0; reg < 8; reg++)
+ supply_register (FP0_REGNUM + reg, FPREG_ADDR (fpregsetp, reg));
+
+ /* We have to mask off the reserved bits in *FPREGSETP before
+ storing the values in GDB's register file. */
+#define supply(REGNO, MEMBER) \
+ l = fpregsetp->MEMBER & 0xffff; \
+ supply_register (REGNO, (char *) &l)
+
+ supply (FCTRL_REGNUM, cwd);
+ supply (FSTAT_REGNUM, swd);
+ supply (FTAG_REGNUM, twd);
supply_register (FCOFF_REGNUM, (char *) &fpregsetp->fip);
- supply_register (FDS_REGNUM, (char *) &fpregsetp->fos);
+ supply (FDS_REGNUM, fos);
supply_register (FDOFF_REGNUM, (char *) &fpregsetp->foo);
-
- /* Extract the code segment and opcode from the "fcs" member. */
- {
- long l;
- l = fpregsetp->fcs & 0xffff;
- supply_register (FCS_REGNUM, (char *) &l);
+#undef supply
- l = (fpregsetp->fcs >> 16) & ((1 << 11) - 1);
- supply_register (FOP_REGNUM, (char *) &l);
- }
+ /* Extract the code segment and opcode from the "fcs" member. */
+ l = fpregsetp->fcs & 0xffff;
+ supply_register (FCS_REGNUM, (char *) &l);
+
+ l = (fpregsetp->fcs >> 16) & ((1 << 11) - 1);
+ supply_register (FOP_REGNUM, (char *) &l);
}
+/* Convert the valid floating-point register values in GDB's register
+ array to `struct user' format and store them in *FPREGSETP. The
+ array VALID indicates which register values are valid. If VALID is
+ NULL, all registers are assumed to be valid. */
-/* Fill in an fpregset_t structure with selected data from a
- gdb-format register file.
- - FPREGSETP points to the structure to be filled.
- - GDB_REGS points to the GDB-style register file providing the data.
- - VALID is an array indicating which registers in GDB_REGS are
- valid; the parts of *FPREGSETP that would hold registers marked
- invalid in GDB_REGS are left unchanged. If VALID is zero, all
- registers are assumed to be valid. */
-void
-convert_to_fpregset (fpregset_t *fpregsetp,
- char *gdb_regs,
- signed char *valid)
+static void
+convert_to_fpregset (elf_fpregset_t *fpregsetp, signed char *valid)
{
- int i;
+ int reg;
/* Fill in the floating-point registers. */
- for (i = 0; i < 8; i++)
- if (!valid || valid[i])
- memcpy (FPREGSET_T_FPREG_OFFSET (fpregsetp, i),
- ®isters[REGISTER_BYTE (FP0_REGNUM + i)],
- REGISTER_RAW_SIZE(FP0_REGNUM + i));
+ for (reg = 0; reg < 8; reg++)
+ if (!valid || valid[reg])
+ memcpy (FPREG_ADDR (fpregsetp, reg),
+ ®isters[REGISTER_BYTE (FP0_REGNUM + reg)],
+ REGISTER_RAW_SIZE(FP0_REGNUM + reg));
+
+ /* We're not supposed to touch the reserved bits in *FPREGSETP. */
#define fill(MEMBER, REGNO) \
if (! valid || valid[(REGNO)]) \
- memcpy (&fpregsetp->MEMBER, ®isters[REGISTER_BYTE (REGNO)], \
- sizeof (fpregsetp->MEMBER))
+ fpregsetp->MEMBER \
+ = ((fpregsetp->MEMBER & ~0xffff) \
+ | (* (int *) ®isters[REGISTER_BYTE (REGNO)] & 0xffff))
+
+#define fill_register(MEMBER, REGNO) \
+ if (! valid || valid[(REGNO)]) \
+ memcpy (&fpregsetp->MEMBER, ®isters[REGISTER_BYTE (REGNO)], \
+ sizeof (fpregsetp->MEMBER))
fill (cwd, FCTRL_REGNUM);
fill (swd, FSTAT_REGNUM);
fill (twd, FTAG_REGNUM);
- fill (fip, FCOFF_REGNUM);
+ fill_register (fip, FCOFF_REGNUM);
fill (foo, FDOFF_REGNUM);
- fill (fos, FDS_REGNUM);
+ fill_register (fos, FDS_REGNUM);
#undef fill
+#undef fill_register
if (! valid || valid[FCS_REGNUM])
fpregsetp->fcs
<< 16));
}
-
-/* Given a pointer to a floating point register set in (fpregset_t *)
- format, update all of the registers from gdb's idea of the current
- floating point register set. */
+/* Fill register REGNO (if it is a floating-point register) in
+ *FPREGSETP with the value in GDB's register array. If REGNO is -1,
+ do this for all registers. */
void
-fill_fpregset (fpregset_t *fpregsetp,
- int regno)
+fill_fpregset (elf_fpregset_t *fpregsetp, int regno)
{
- convert_to_fpregset (fpregsetp, registers, 0);
+ if (regno == -1)
+ {
+ convert_to_fpregset (fpregsetp, NULL);
+ return;
+ }
+
+ if (GETFPREGS_SUPPLIES(regno))
+ {
+ signed char valid[MAX_NUM_REGS];
+
+ memset (valid, 0, sizeof (valid));
+ valid[regno] = 1;
+
+ convert_to_fpregset (fpregsetp, valid);
+ }
}
+#ifdef HAVE_PTRACE_GETREGS
+
+/* Fetch all floating-point registers from process/thread TID and store
+ thier values in GDB's register array. */
-/* Get the whole floating point state of the process and store the
- floating point stack into registers[]. */
static void
-fetch_fpregs ()
+fetch_fpregs (int tid)
{
- int ret, regno;
- fpregset_t buf;
+ elf_fpregset_t fpregs;
+ int ret;
- ret = ptrace (PTRACE_GETFPREGS, inferior_pid, 0, (int) &buf);
+ ret = ptrace (PTRACE_GETFPREGS, tid, 0, (int) &fpregs);
if (ret < 0)
{
- warning ("Couldn't get floating point status");
+ warning ("Couldn't get floating point status.");
return;
}
- /* ptrace fills an fpregset_t, so we can use the same function we do
- for core files. */
- supply_fpregset (&buf);
+ supply_fpregset (&fpregs);
}
+/* Store all valid floating-point registers in GDB's register array
+ into the process/thread specified by TID. */
-/* Set the inferior's floating-point registers to the values in
- registers[] --- but only those registers marked valid. */
static void
-store_fpregs ()
+store_fpregs (int tid)
{
+ elf_fpregset_t fpregs;
int ret;
- fpregset_t buf;
- ret = ptrace (PTRACE_GETFPREGS, inferior_pid, 0, (int) &buf);
+ ret = ptrace (PTRACE_GETFPREGS, tid, 0, (int) &fpregs);
if (ret < 0)
{
- warning ("Couldn't get floating point status");
+ warning ("Couldn't get floating point status.");
return;
}
- convert_to_fpregset (&buf, registers, register_valid);
+ convert_to_fpregset (&fpregs, register_valid);
- ret = ptrace (PTRACE_SETFPREGS, inferior_pid, 0, (int) &buf);
+ ret = ptrace (PTRACE_SETFPREGS, tid, 0, (int) &fpregs);
if (ret < 0)
{
- warning ("Couldn't write floating point status");
+ warning ("Couldn't write floating point status.");
return;
}
}
+#else
+
+static void fetch_fpregs (int tid) {}
+static void store_fpregs (int tid) {}
+
+#endif
+
+\f
+/* Transfering floating-point and SSE registers to and from GDB. */
+
+/* PTRACE_GETXFPREGS is a Cygnus invention, since we wrote our own
+ Linux kernel patch for SSE support. That patch may or may not
+ actually make it into the official distribution. If you find that
+ years have gone by since this code was added, and Linux isn't using
+ PTRACE_GETXFPREGS, that means that our patch didn't make it, and
+ you can delete this code. */
+
+#ifdef HAVE_PTRACE_GETXFPREGS
+
+/* Fill GDB's register array with the floating-point and SSE register
+ values in *XFPREGS. */
-/* Read the general registers from the process, and store them
- in registers[]. */
static void
-fetch_regs ()
+supply_xfpregset (struct user_xfpregs_struct *xfpregs)
{
- int ret, regno;
- gregset_t buf;
+ int reg;
- ret = ptrace (PTRACE_GETREGS, inferior_pid, 0, (int) &buf);
- if (ret < 0)
+ /* Supply the floating-point registers. */
+ for (reg = 0; reg < 8; reg++)
+ supply_register (FP0_REGNUM + reg, (char *) &xfpregs->st_space[reg]);
+
+ {
+ supply_register (FCTRL_REGNUM, (char *) &xfpregs->cwd);
+ supply_register (FSTAT_REGNUM, (char *) &xfpregs->swd);
+ supply_register (FTAG_REGNUM, (char *) &xfpregs->twd);
+ supply_register (FCOFF_REGNUM, (char *) &xfpregs->fip);
+ supply_register (FDS_REGNUM, (char *) &xfpregs->fos);
+ supply_register (FDOFF_REGNUM, (char *) &xfpregs->foo);
+
+ /* Extract the code segment and opcode from the "fcs" member. */
{
- warning ("Couldn't get registers");
- return;
+ long l;
+
+ l = xfpregs->fcs & 0xffff;
+ supply_register (FCS_REGNUM, (char *) &l);
+
+ l = (xfpregs->fcs >> 16) & ((1 << 11) - 1);
+ supply_register (FOP_REGNUM, (char *) &l);
}
+ }
- supply_gregset (&buf);
+ /* Supply the SSE registers. */
+ for (reg = 0; reg < 8; reg++)
+ supply_register (XMM0_REGNUM + reg, (char *) &xfpregs->xmm_space[reg]);
+ supply_register (MXCSR_REGNUM, (char *) &xfpregs->mxcsr);
}
+/* Convert the valid floating-point and SSE registers in GDB's
+ register array to `struct user' format and store them in *XFPREGS.
+ The array VALID indicates which registers are valid. If VALID is
+ NULL, all registers are assumed to be valid. */
-/* Set the inferior's general registers to the values in registers[]
- --- but only those registers marked as valid. */
static void
-store_regs ()
+convert_to_xfpregset (struct user_xfpregs_struct *xfpregs,
+ signed char *valid)
{
- int ret, regno;
- gregset_t buf;
+ int reg;
- ret = ptrace (PTRACE_GETREGS, inferior_pid, 0, (int) &buf);
- if (ret < 0)
+ /* Fill in the floating-point registers. */
+ for (reg = 0; reg < 8; reg++)
+ if (!valid || valid[reg])
+ memcpy (&xfpregs->st_space[reg],
+ ®isters[REGISTER_BYTE (FP0_REGNUM + reg)],
+ REGISTER_RAW_SIZE(FP0_REGNUM + reg));
+
+#define fill(MEMBER, REGNO) \
+ if (! valid || valid[(REGNO)]) \
+ memcpy (&xfpregs->MEMBER, ®isters[REGISTER_BYTE (REGNO)], \
+ sizeof (xfpregs->MEMBER))
+
+ fill (cwd, FCTRL_REGNUM);
+ fill (swd, FSTAT_REGNUM);
+ fill (twd, FTAG_REGNUM);
+ fill (fip, FCOFF_REGNUM);
+ fill (foo, FDOFF_REGNUM);
+ fill (fos, FDS_REGNUM);
+
+#undef fill
+
+ if (! valid || valid[FCS_REGNUM])
+ xfpregs->fcs
+ = ((xfpregs->fcs & ~0xffff)
+ | (* (int *) ®isters[REGISTER_BYTE (FCS_REGNUM)] & 0xffff));
+
+ if (! valid || valid[FOP_REGNUM])
+ xfpregs->fcs
+ = ((xfpregs->fcs & 0xffff)
+ | ((*(int *) ®isters[REGISTER_BYTE (FOP_REGNUM)] & ((1 << 11) - 1))
+ << 16));
+
+ /* Fill in the XMM registers. */
+ for (reg = 0; reg < 8; reg++)
+ if (! valid || valid[reg])
+ memcpy (&xfpregs->xmm_space[reg],
+ ®isters[REGISTER_BYTE (XMM0_REGNUM + reg)],
+ REGISTER_RAW_SIZE (XMM0_REGNUM + reg));
+}
+
+/* Fetch all registers covered by the PTRACE_SETXFPREGS request from
+ process/thread TID and store their values in GDB's register array.
+ Return non-zero if successful, zero otherwise. */
+
+static int
+fetch_xfpregs (int tid)
+{
+ struct user_xfpregs_struct xfpregs;
+ int ret;
+
+ if (! have_ptrace_getxfpregs)
+ return 0;
+
+ ret = ptrace (PTRACE_GETXFPREGS, tid, 0, &xfpregs);
+ if (ret == -1)
{
- warning ("Couldn't get registers");
- return;
+ if (errno == EIO)
+ {
+ have_ptrace_getxfpregs = 0;
+ return 0;
+ }
+
+ warning ("Couldn't read floating-point and SSE registers.");
+ return 0;
}
- convert_to_gregset (&buf, registers, register_valid);
+ supply_xfpregset (&xfpregs);
+ return 1;
+}
- ret = ptrace (PTRACE_SETREGS, inferior_pid, 0, (int)buf);
- if (ret < 0)
+/* Store all valid registers in GDB's register array covered by the
+ PTRACE_SETXFPREGS request into the process/thread specified by TID.
+ Return non-zero if successful, zero otherwise. */
+
+static int
+store_xfpregs (int tid)
+{
+ struct user_xfpregs_struct xfpregs;
+ int ret;
+
+ if (! have_ptrace_getxfpregs)
+ return 0;
+
+ ret = ptrace (PTRACE_GETXFPREGS, tid, 0, &xfpregs);
+ if (ret == -1)
{
- warning ("Couldn't write registers");
- return;
+ if (errno == EIO)
+ {
+ have_ptrace_getxfpregs = 0;
+ return 0;
+ }
+
+ warning ("Couldn't read floating-point and SSE registers.");
+ return 0;
+ }
+
+ convert_to_xfpregset (&xfpregs, register_valid);
+
+ if (ptrace (PTRACE_SETXFPREGS, tid, 0, &xfpregs) < 0)
+ {
+ warning ("Couldn't write floating-point and SSE registers.");
+ return 0;
}
+
+ return 1;
+}
+
+/* Fill the XMM registers in the register array with dummy values. For
+ cases where we don't have access to the XMM registers. I think
+ this is cleaner than printing a warning. For a cleaner solution,
+ we should gdbarchify the i386 family. */
+
+static void
+dummy_sse_values (void)
+{
+ /* C doesn't have a syntax for NaN's, so write it out as an array of
+ longs. */
+ static long dummy[4] = { 0xffffffff, 0xffffffff, 0xffffffff, 0xffffffff };
+ static long mxcsr = 0x1f80;
+ int reg;
+
+ for (reg = 0; reg < 8; reg++)
+ supply_register (XMM0_REGNUM + reg, (char *) dummy);
+ supply_register (MXCSR_REGNUM, (char *) &mxcsr);
}
+#else
-/* Fetch registers from the child process.
- Fetch all if regno == -1, otherwise fetch all ordinary
- registers or all floating point registers depending
- upon the value of regno. */
+/* Stub versions of the above routines, for systems that don't have
+ PTRACE_GETXFPREGS. */
+static int store_xfpregs (int tid) { return 0; }
+static int fetch_xfpregs (int tid) { return 0; }
+static void dummy_sse_values (void) {}
+
+#endif
+
+\f
+/* Transferring arbitrary registers between GDB and inferior. */
+
+/* Fetch register REGNO from the child process. If REGNO is -1, do
+ this for all registers (including the floating point and SSE
+ registers). */
void
fetch_inferior_registers (int regno)
{
- if (regno < NUM_GREGS || regno == -1)
- fetch_regs ();
+ int tid;
+
+ /* Use the old method of peeking around in `struct user' if the
+ GETREGS request isn't available. */
+ if (! have_ptrace_getregs)
+ {
+ old_fetch_inferior_registers (regno);
+ return;
+ }
+
+ /* Linux LWP ID's are process ID's. */
+ if ((tid = TIDGET (inferior_pid)) == 0)
+ tid = inferior_pid; /* Not a threaded program. */
+
+ /* Use the PTRACE_GETXFPREGS request whenever possible, since it
+ transfers more registers in one system call, and we'll cache the
+ results. But remember that fetch_xfpregs can fail, and return
+ zero. */
+ if (regno == -1)
+ {
+ fetch_regs (tid);
+
+ /* The call above might reset `have_ptrace_getregs'. */
+ if (! have_ptrace_getregs)
+ {
+ old_fetch_inferior_registers (-1);
+ return;
+ }
+
+ if (fetch_xfpregs (tid))
+ return;
+ fetch_fpregs (tid);
+ return;
+ }
+
+ if (GETREGS_SUPPLIES (regno))
+ {
+ fetch_regs (tid);
+ return;
+ }
+
+ if (GETXFPREGS_SUPPLIES (regno))
+ {
+ if (fetch_xfpregs (tid))
+ return;
+
+ /* Either our processor or our kernel doesn't support the SSE
+ registers, so read the FP registers in the traditional way,
+ and fill the SSE registers with dummy values. It would be
+ more graceful to handle differences in the register set using
+ gdbarch. Until then, this will at least make things work
+ plausibly. */
+ fetch_fpregs (tid);
+ dummy_sse_values ();
+ return;
+ }
+
+ internal_error ("i386-linux-nat.c (fetch_inferior_registers): "
+ "got request for bad register number %d", regno);
+}
+
+/* Store register REGNO back into the child process. If REGNO is -1,
+ do this for all registers (including the floating point and SSE
+ registers). */
+void
+store_inferior_registers (int regno)
+{
+ int tid;
+
+ /* Use the old method of poking around in `struct user' if the
+ SETREGS request isn't available. */
+ if (! have_ptrace_getregs)
+ {
+ old_store_inferior_registers (regno);
+ return;
+ }
- if (regno >= NUM_GREGS || regno == -1)
- fetch_fpregs ();
+ /* Linux LWP ID's are process ID's. */
+ if ((tid = TIDGET (inferior_pid)) == 0)
+ tid = inferior_pid; /* Not a threaded program. */
+
+ /* Use the PTRACE_SETXFPREGS requests whenever possibl, since it
+ transfers more registers in one system call. But remember that
+ store_xfpregs can fail, and return zero. */
+ if (regno == -1)
+ {
+ store_regs (tid);
+ if (store_xfpregs (tid))
+ return;
+ store_fpregs (tid);
+ return;
+ }
+
+ if (GETREGS_SUPPLIES (regno))
+ {
+ store_regs (tid);
+ return;
+ }
+
+ if (GETXFPREGS_SUPPLIES (regno))
+ {
+ if (store_xfpregs (tid))
+ return;
+
+ /* Either our processor or our kernel doesn't support the SSE
+ registers, so just write the FP registers in the traditional
+ way. */
+ store_fpregs (tid);
+ return;
+ }
+
+ internal_error ("Got request to store bad register number %d.", regno);
}
+\f
+/* Interpreting register set info found in core files. */
-/* Store our register values back into the inferior.
- If REGNO is -1, do this for all registers.
- Otherwise, REGNO specifies which register, which
- then determines whether we store all ordinary
- registers or all of the floating point registers. */
+/* Provide registers to GDB from a core file.
+
+ (We can't use the generic version of this function in
+ core-regset.c, because Linux has *three* different kinds of
+ register set notes. core-regset.c would have to call
+ supply_xfpregset, which most platforms don't have.)
+
+ CORE_REG_SECT points to an array of bytes, which are the contents
+ of a `note' from a core file which BFD thinks might contain
+ register contents. CORE_REG_SIZE is its size.
+
+ WHICH says which register set corelow suspects this is:
+ 0 --- the general-purpose register set, in elf_gregset_t format
+ 2 --- the floating-point register set, in elf_fpregset_t format
+ 3 --- the extended floating-point register set, in struct
+ user_xfpregs_struct format
+
+ REG_ADDR isn't used on Linux. */
+
+static void
+fetch_core_registers (char *core_reg_sect, unsigned core_reg_size,
+ int which, CORE_ADDR reg_addr)
+{
+ elf_gregset_t gregset;
+ elf_fpregset_t fpregset;
+
+ switch (which)
+ {
+ case 0:
+ if (core_reg_size != sizeof (gregset))
+ warning ("Wrong size gregset in core file.");
+ else
+ {
+ memcpy (&gregset, core_reg_sect, sizeof (gregset));
+ supply_gregset (&gregset);
+ }
+ break;
+
+ case 2:
+ if (core_reg_size != sizeof (fpregset))
+ warning ("Wrong size fpregset in core file.");
+ else
+ {
+ memcpy (&fpregset, core_reg_sect, sizeof (fpregset));
+ supply_fpregset (&fpregset);
+ }
+ break;
+
+#ifdef HAVE_PTRACE_GETXFPREGS
+ {
+ struct user_xfpregs_struct xfpregset;
+
+ case 3:
+ if (core_reg_size != sizeof (xfpregset))
+ warning ("Wrong size user_xfpregs_struct in core file.");
+ else
+ {
+ memcpy (&xfpregset, core_reg_sect, sizeof (xfpregset));
+ supply_xfpregset (&xfpregset);
+ }
+ break;
+ }
+#endif
+
+ default:
+ /* We've covered all the kinds of registers we know about here,
+ so this must be something we wouldn't know what to do with
+ anyway. Just ignore it. */
+ break;
+ }
+}
+
+\f
+/* The instruction for a Linux system call is:
+ int $0x80
+ or 0xcd 0x80. */
+
+static const unsigned char linux_syscall[] = { 0xcd, 0x80 };
+
+#define LINUX_SYSCALL_LEN (sizeof linux_syscall)
+
+/* The system call number is stored in the %eax register. */
+#define LINUX_SYSCALL_REGNUM 0 /* %eax */
+
+/* We are specifically interested in the sigreturn and rt_sigreturn
+ system calls. */
+
+#ifndef SYS_sigreturn
+#define SYS_sigreturn 0x77
+#endif
+#ifndef SYS_rt_sigreturn
+#define SYS_rt_sigreturn 0xad
+#endif
+
+/* Offset to saved processor flags, from <asm/sigcontext.h>. */
+#define LINUX_SIGCONTEXT_EFLAGS_OFFSET (64)
+
+/* Resume execution of the inferior process.
+ If STEP is nonzero, single-step it.
+ If SIGNAL is nonzero, give it that signal. */
void
-store_inferior_registers (regno)
- int regno;
+child_resume (int pid, int step, enum target_signal signal)
{
- if (regno < NUM_GREGS || regno == -1)
- store_regs ();
+ int request = PTRACE_CONT;
+
+ if (pid == -1)
+ /* Resume all threads. */
+ /* I think this only gets used in the non-threaded case, where "resume
+ all threads" and "resume inferior_pid" are the same. */
+ pid = inferior_pid;
+
+ if (step)
+ {
+ CORE_ADDR pc = read_pc_pid (pid);
+ unsigned char buf[LINUX_SYSCALL_LEN];
+
+ request = PTRACE_SINGLESTEP;
+
+ /* Returning from a signal trampoline is done by calling a
+ special system call (sigreturn or rt_sigreturn, see
+ i386-linux-tdep.c for more information). This system call
+ restores the registers that were saved when the signal was
+ raised, including %eflags. That means that single-stepping
+ won't work. Instead, we'll have to modify the signal context
+ that's about to be restored, and set the trace flag there. */
+
+ /* First check if PC is at a system call. */
+ if (read_memory_nobpt (pc, (char *) buf, LINUX_SYSCALL_LEN) == 0
+ && memcmp (buf, linux_syscall, LINUX_SYSCALL_LEN) == 0)
+ {
+ int syscall = read_register_pid (LINUX_SYSCALL_REGNUM, pid);
+
+ /* Then check the system call number. */
+ if (syscall == SYS_sigreturn || syscall == SYS_rt_sigreturn)
+ {
+ CORE_ADDR sp = read_register (SP_REGNUM);
+ CORE_ADDR addr = sp;
+ unsigned long int eflags;
+
+ if (syscall == SYS_rt_sigreturn)
+ addr = read_memory_integer (sp + 8, 4) + 20;
+
+ /* Set the trace flag in the context that's about to be
+ restored. */
+ addr += LINUX_SIGCONTEXT_EFLAGS_OFFSET;
+ read_memory (addr, (char *) &eflags, 4);
+ eflags |= 0x0100;
+ write_memory (addr, (char *) &eflags, 4);
+ }
+ }
+ }
- if (regno >= NUM_GREGS || regno == -1)
- store_fpregs ();
+ if (ptrace (request, pid, 0, target_signal_to_host (signal)) == -1)
+ perror_with_name ("ptrace");
}
+\f
+/* Calling functions in shared libraries. */
+/* FIXME: kettenis/2000-03-05: Doesn't this belong in a
+ target-dependent file? The function
+ `i386_linux_skip_solib_resolver' is mentioned in
+ `config/i386/tm-linux.h'. */
/* Find the minimal symbol named NAME, and return both the minsym
struct and its objfile. This probably ought to be in minsym.c, but
return 0;
}
-
/* See the comments for SKIP_SOLIB_RESOLVER at the top of infrun.c.
This function:
1) decides whether a PLT has sent us into the linker to resolve
return 0;
}
+
+\f
+/* Register that we are able to handle Linux ELF core file formats. */
+
+static struct core_fns linux_elf_core_fns =
+{
+ bfd_target_elf_flavour, /* core_flavour */
+ default_check_format, /* check_format */
+ default_core_sniffer, /* core_sniffer */
+ fetch_core_registers, /* core_read_registers */
+ NULL /* next */
+};
+
+void
+_initialize_i386_linux_nat ()
+{
+ add_core_fns (&linux_elf_core_fns);
+}
projects / deliverable / binutils-gdb.git / blobdiff