-/* Native-dependent code for Linux running on i386's, for GDB.
+/* Native-dependent code for Linux/x86.
+ Copyright 1999, 2000 Free Software Foundation, Inc.
This file is part of GDB.
#include "inferior.h"
#include "gdbcore.h"
-/* For i386_linux_skip_solib_resolver. */
-#include "symtab.h"
-#include "frame.h"
-#include "symfile.h"
-#include "objfiles.h"
-
#include <sys/ptrace.h>
#include <sys/user.h>
#include <sys/procfs.h>
#include <sys/reg.h>
#endif
+/* Prototypes for supply_gregset etc. */
+#include "gregset.h"
+
+/* Prototypes for i387_supply_fsave etc. */
+#include "i387-nat.h"
+
+/* Prototypes for local functions. */
+static void dummy_sse_values (void);
+
/* 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
#define PIDGET(PID) PID
#define TIDGET(PID) 0
#endif
-
+\f
/* 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,
(0 <= (regno) && (regno) <= 15)
#define GETFPREGS_SUPPLIES(regno) \
(FP0_REGNUM <= (regno) && (regno) <= LAST_FPU_CTRL_REGNUM)
-#define GETXFPREGS_SUPPLIES(regno) \
+#define GETFPXREGS_SUPPLIES(regno) \
(FP0_REGNUM <= (regno) && (regno) <= MXCSR_REGNUM)
/* Does the current host support the GETREGS request? */
#endif
;
-/* Does the current host support the GETXFPREGS request? The header
+/* Does the current host support the GETFPXREGS 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
+int have_ptrace_getfpxregs =
+#ifdef HAVE_PTRACE_GETFPXREGS
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
the GETREGS request. I want to avoid changing `infptrace.c' right
now. */
+#ifndef PT_READ_U
+#define PT_READ_U PTRACE_PEEKUSR
+#endif
+#ifndef PT_WRITE_U
+#define PT_WRITE_U PTRACE_POKEUSR
+#endif
+
/* 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
+#define OLD_CANNOT_FETCH_REGISTER(regno) ((regno) >= NUM_GREGS)
/* Fetch one register. */
static void
-fetch_register (regno)
- int regno;
+fetch_register (int regno)
{
/* This isn't really an address. But ptrace thinks of it as one. */
CORE_ADDR regaddr;
char buf[MAX_REGISTER_RAW_SIZE];
int tid;
- if (CANNOT_FETCH_REGISTER (regno))
+ if (OLD_CANNOT_FETCH_REGISTER (regno))
{
memset (buf, '\0', REGISTER_RAW_SIZE (regno)); /* Supply zeroes */
supply_register (regno, buf);
Otherwise, REGNO specifies which register (so we can save time). */
void
-old_fetch_inferior_registers (regno)
- int regno;
+old_fetch_inferior_registers (int regno)
{
if (regno >= 0)
{
}
/* Registers we shouldn't try to store. */
-#if !defined (CANNOT_STORE_REGISTER)
-#define CANNOT_STORE_REGISTER(regno) 0
-#endif
+#define OLD_CANNOT_STORE_REGISTER(regno) ((regno) >= NUM_GREGS)
/* Store one register. */
static void
-store_register (regno)
- int regno;
+store_register (int regno)
{
/* This isn't really an address. But ptrace thinks of it as one. */
CORE_ADDR regaddr;
unsigned int offset; /* Offset of registers within the u area. */
int tid;
- if (CANNOT_STORE_REGISTER (regno))
+ if (OLD_CANNOT_STORE_REGISTER (regno))
{
return;
}
Otherwise, REGNO specifies which register (so we can save time). */
void
-old_store_inferior_registers (regno)
- int regno;
+old_store_inferior_registers (int regno)
{
if (regno >= 0)
{
}
}
}
-
\f
+
/* Transfering the general-purpose registers between GDB, inferiors
and core files. */
-/* Fill GDB's register array with the genereal-purpose register values
+/* Fill GDB's register array with the general-purpose register values
in *GREGSETP. */
void
supply_gregset (elf_gregset_t *gregsetp)
{
elf_greg_t *regp = (elf_greg_t *) gregsetp;
- int regi;
+ int i;
- 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;
-
- for (regi = 0; regi < NUM_GREGS; regi++)
- if (! valid || valid[regi])
- *(regp + regmap[regi]) = * (int *) ®isters[REGISTER_BYTE (regi)];
+ for (i = 0; i < NUM_GREGS; i++)
+ supply_register (i, (char *) (regp + regmap[i]));
}
/* 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 (elf_gregset_t *gregsetp, int regno)
{
- if (regno == -1)
- {
- convert_to_gregset (gregsetp, NULL);
- return;
- }
-
- if (GETREGS_SUPPLIES (regno))
- {
- signed char valid[NUM_GREGS];
-
- memset (valid, 0, sizeof (valid));
- valid[regno] = 1;
+ elf_greg_t *regp = (elf_greg_t *) gregsetp;
+ int i;
- convert_to_gregset (gregsetp, valid);
- }
+ for (i = 0; i < NUM_GREGS; i++)
+ if ((regno == -1 || regno == i))
+ *(regp + regmap[i]) = *(elf_greg_t *) ®isters[REGISTER_BYTE (i)];
}
#ifdef HAVE_PTRACE_GETREGS
fetch_regs (int tid)
{
elf_gregset_t regs;
- int ret;
- ret = ptrace (PTRACE_GETREGS, tid, 0, (int) ®s);
- if (ret < 0)
+ if (ptrace (PTRACE_GETREGS, tid, 0, (int) ®s) < 0)
{
if (errno == EIO)
{
return;
}
- warning ("Couldn't get registers.");
- return;
+ perror_with_name ("Couldn't get registers");
}
supply_gregset (®s);
into the process/thread specified by TID. */
static void
-store_regs (int tid)
+store_regs (int tid, int regno)
{
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);
+ if (ptrace (PTRACE_GETREGS, tid, 0, (int) ®s) < 0)
+ perror_with_name ("Couldn't get registers");
- ret = ptrace (PTRACE_SETREGS, tid, 0, (int) ®s);
- if (ret < 0)
- {
- warning ("Couldn't write registers.");
- return;
- }
+ fill_gregset (®s, regno);
+
+ if (ptrace (PTRACE_SETREGS, tid, 0, (int) ®s) < 0)
+ perror_with_name ("Couldn't write registers");
}
#else
static void fetch_regs (int tid) {}
-static void store_regs (int tid) {}
+static void store_regs (int tid, int regno) {}
#endif
-
\f
-/* Transfering floating-point registers between GDB, inferiors and cores. */
-/* 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)
+/* Transfering floating-point registers between GDB, inferiors and cores. */
/* Fill GDB's register array with the floating-point register values in
*FPREGSETP. */
void
supply_fpregset (elf_fpregset_t *fpregsetp)
{
- int reg;
- long l;
-
- /* Supply the floating-point registers. */
- 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 (FDS_REGNUM, fos);
- supply_register (FDOFF_REGNUM, (char *) &fpregsetp->foo);
-
-#undef supply
-
- /* 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. */
-
-static void
-convert_to_fpregset (elf_fpregset_t *fpregsetp, signed char *valid)
-{
- int reg;
-
- /* Fill in the floating-point registers. */
- 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)]) \
- 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_register (fip, FCOFF_REGNUM);
- fill (foo, FDOFF_REGNUM);
- fill_register (fos, FDS_REGNUM);
-
-#undef fill
-#undef fill_register
-
- if (! valid || valid[FCS_REGNUM])
- fpregsetp->fcs
- = ((fpregsetp->fcs & ~0xffff)
- | (* (int *) ®isters[REGISTER_BYTE (FCS_REGNUM)] & 0xffff));
-
- if (! valid || valid[FOP_REGNUM])
- fpregsetp->fcs
- = ((fpregsetp->fcs & 0xffff)
- | ((*(int *) ®isters[REGISTER_BYTE (FOP_REGNUM)] & ((1 << 11) - 1))
- << 16));
+ i387_supply_fsave ((char *) fpregsetp);
+ dummy_sse_values ();
}
/* Fill register REGNO (if it is a floating-point register) in
void
fill_fpregset (elf_fpregset_t *fpregsetp, int regno)
{
- 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);
- }
+ i387_fill_fsave ((char *) fpregsetp, regno);
}
#ifdef HAVE_PTRACE_GETREGS
fetch_fpregs (int tid)
{
elf_fpregset_t fpregs;
- int ret;
- ret = ptrace (PTRACE_GETFPREGS, tid, 0, (int) &fpregs);
- if (ret < 0)
- {
- warning ("Couldn't get floating point status.");
- return;
- }
+ if (ptrace (PTRACE_GETFPREGS, tid, 0, (int) &fpregs) < 0)
+ perror_with_name ("Couldn't get floating point status");
supply_fpregset (&fpregs);
}
into the process/thread specified by TID. */
static void
-store_fpregs (int tid)
+store_fpregs (int tid, int regno)
{
elf_fpregset_t fpregs;
- int ret;
- ret = ptrace (PTRACE_GETFPREGS, tid, 0, (int) &fpregs);
- if (ret < 0)
- {
- warning ("Couldn't get floating point status.");
- return;
- }
+ if (ptrace (PTRACE_GETFPREGS, tid, 0, (int) &fpregs) < 0)
+ perror_with_name ("Couldn't get floating point status");
- convert_to_fpregset (&fpregs, register_valid);
+ fill_fpregset (&fpregs, regno);
- ret = ptrace (PTRACE_SETFPREGS, tid, 0, (int) &fpregs);
- if (ret < 0)
- {
- warning ("Couldn't write floating point status.");
- return;
- }
+ if (ptrace (PTRACE_SETFPREGS, tid, 0, (int) &fpregs) < 0)
+ perror_with_name ("Couldn't write floating point status");
}
#else
static void fetch_fpregs (int tid) {}
-static void store_fpregs (int tid) {}
+static void store_fpregs (int tid, int regno) {}
#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. */
+/* Transfering floating-point and SSE registers to and from GDB. */
-#ifdef HAVE_PTRACE_GETXFPREGS
+#ifdef HAVE_PTRACE_GETFPXREGS
/* Fill GDB's register array with the floating-point and SSE register
- values in *XFPREGS. */
+ values in *FPXREGSETP. */
static void
-supply_xfpregset (struct user_xfpregs_struct *xfpregs)
+supply_fpxregset (elf_fpxregset_t *fpxregsetp)
{
- int reg;
-
- /* 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. */
- {
- 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 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);
+ i387_supply_fxsave ((char *) fpxregsetp);
}
-/* 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. */
+/* Fill register REGNO (if it is a floating-point or SSE register) in
+ *FPXREGSETP with the value in GDB's register array. If REGNO is
+ -1, do this for all registers. */
static void
-convert_to_xfpregset (struct user_xfpregs_struct *xfpregs,
- signed char *valid)
+fill_fpxregset (elf_fpxregset_t *fpxregsetp, int regno)
{
- int reg;
-
- /* 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));
+ i387_fill_fxsave ((char *) fpxregsetp, regno);
}
-/* Fetch all registers covered by the PTRACE_SETXFPREGS request from
+/* Fetch all registers covered by the PTRACE_GETFPXREGS 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)
+fetch_fpxregs (int tid)
{
- struct user_xfpregs_struct xfpregs;
- int ret;
+ elf_fpxregset_t fpxregs;
- if (! have_ptrace_getxfpregs)
+ if (! have_ptrace_getfpxregs)
return 0;
- ret = ptrace (PTRACE_GETXFPREGS, tid, 0, &xfpregs);
- if (ret == -1)
+ if (ptrace (PTRACE_GETFPXREGS, tid, 0, (int) &fpxregs) < 0)
{
if (errno == EIO)
{
- have_ptrace_getxfpregs = 0;
+ have_ptrace_getfpxregs = 0;
return 0;
}
- warning ("Couldn't read floating-point and SSE registers.");
- return 0;
+ perror_with_name ("Couldn't read floating-point and SSE registers");
}
- supply_xfpregset (&xfpregs);
+ supply_fpxregset (&fpxregs);
return 1;
}
/* Store all valid registers in GDB's register array covered by the
- PTRACE_SETXFPREGS request into the process/thread specified by TID.
+ PTRACE_SETFPXREGS request into the process/thread specified by TID.
Return non-zero if successful, zero otherwise. */
static int
-store_xfpregs (int tid)
+store_fpxregs (int tid, int regno)
{
- struct user_xfpregs_struct xfpregs;
- int ret;
+ elf_fpxregset_t fpxregs;
- if (! have_ptrace_getxfpregs)
+ if (! have_ptrace_getfpxregs)
return 0;
-
- ret = ptrace (PTRACE_GETXFPREGS, tid, 0, &xfpregs);
- if (ret == -1)
+
+ if (ptrace (PTRACE_GETFPXREGS, tid, 0, &fpxregs) == -1)
{
if (errno == EIO)
{
- have_ptrace_getxfpregs = 0;
+ have_ptrace_getfpxregs = 0;
return 0;
}
- warning ("Couldn't read floating-point and SSE registers.");
- return 0;
+ perror_with_name ("Couldn't read floating-point and SSE registers");
}
- convert_to_xfpregset (&xfpregs, register_valid);
+ fill_fpxregset (&fpxregs, regno);
- if (ptrace (PTRACE_SETXFPREGS, tid, 0, &xfpregs) < 0)
- {
- warning ("Couldn't write floating-point and SSE registers.");
- return 0;
- }
+ if (ptrace (PTRACE_SETFPXREGS, tid, 0, &fpxregs) == -1)
+ perror_with_name ("Couldn't write floating-point and SSE registers");
return 1;
}
#else
-/* 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 int fetch_fpxregs (int tid) { return 0; }
+static int store_fpxregs (int tid, int regno) { return 0; }
static void dummy_sse_values (void) {}
-#endif
-
+#endif /* HAVE_PTRACE_GETFPXREGS */
\f
+
/* Transferring arbitrary registers between GDB and inferior. */
+/* Check if register REGNO in the child process is accessible.
+ If we are accessing registers directly via the U area, only the
+ general-purpose registers are available.
+ All registers should be accessible if we have GETREGS support. */
+
+int
+cannot_fetch_register (int regno)
+{
+ if (! have_ptrace_getregs)
+ return OLD_CANNOT_FETCH_REGISTER (regno);
+ return 0;
+}
+int
+cannot_store_register (int regno)
+{
+ if (! have_ptrace_getregs)
+ return OLD_CANNOT_STORE_REGISTER (regno);
+ return 0;
+}
+
/* Fetch register REGNO from the child process. If REGNO is -1, do
this for all registers (including the floating point and SSE
registers). */
if ((tid = TIDGET (inferior_pid)) == 0)
tid = inferior_pid; /* Not a threaded program. */
- /* Use the PTRACE_GETXFPREGS request whenever possible, since it
+ /* Use the PTRACE_GETFPXREGS 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
+ results. But remember that fetch_fpxregs can fail, and return
zero. */
if (regno == -1)
{
return;
}
- if (fetch_xfpregs (tid))
+ if (fetch_fpxregs (tid))
return;
fetch_fpregs (tid);
return;
return;
}
- if (GETXFPREGS_SUPPLIES (regno))
+ if (GETFPXREGS_SUPPLIES (regno))
{
- if (fetch_xfpregs (tid))
+ if (fetch_fpxregs (tid))
return;
/* Either our processor or our kernel doesn't support the SSE
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);
+ internal_error ("Got request for bad register number %d.", regno);
}
/* Store register REGNO back into the child process. If REGNO is -1,
if ((tid = TIDGET (inferior_pid)) == 0)
tid = inferior_pid; /* Not a threaded program. */
- /* Use the PTRACE_SETXFPREGS requests whenever possibl, since it
+ /* Use the PTRACE_SETFPXREGS requests whenever possible, since it
transfers more registers in one system call. But remember that
- store_xfpregs can fail, and return zero. */
+ store_fpxregs can fail, and return zero. */
if (regno == -1)
{
- store_regs (tid);
- if (store_xfpregs (tid))
+ store_regs (tid, regno);
+ if (store_fpxregs (tid, regno))
return;
- store_fpregs (tid);
+ store_fpregs (tid, regno);
return;
}
if (GETREGS_SUPPLIES (regno))
{
- store_regs (tid);
+ store_regs (tid, regno);
return;
}
- if (GETXFPREGS_SUPPLIES (regno))
+ if (GETFPXREGS_SUPPLIES (regno))
{
- if (store_xfpregs (tid))
+ if (store_fpxregs (tid, regno))
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);
+ store_fpregs (tid, regno);
return;
}
internal_error ("Got request to store bad register number %d.", regno);
}
-
\f
+
/* Interpreting register set info found in core files. */
/* 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.)
+ supply_fpxregset, 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
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
+ 3 --- the extended floating-point register set, in elf_fpxregset_t format
REG_ADDR isn't used on Linux. */
}
break;
-#ifdef HAVE_PTRACE_GETXFPREGS
+#ifdef HAVE_PTRACE_GETFPXREGS
{
- struct user_xfpregs_struct xfpregset;
+ elf_fpxregset_t fpxregset;
case 3:
- if (core_reg_size != sizeof (xfpregset))
- warning ("Wrong size user_xfpregs_struct in core file.");
+ if (core_reg_size != sizeof (fpxregset))
+ warning ("Wrong size fpxregset in core file.");
else
{
- memcpy (&xfpregset, core_reg_sect, sizeof (xfpregset));
- supply_xfpregset (&xfpregset);
+ memcpy (&fpxregset, core_reg_sect, sizeof (fpxregset));
+ supply_fpxregset (&fpxregset);
}
break;
}
break;
}
}
-
\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
- everything there is trying to deal with things like C++ and
- SOFUN_ADDRESS_MAYBE_TURQUOISE, ... Since this is so simple, it may
- be considered too special-purpose for general consumption. */
-
-static struct minimal_symbol *
-find_minsym_and_objfile (char *name, struct objfile **objfile_p)
-{
- struct objfile *objfile;
- ALL_OBJFILES (objfile)
- {
- struct minimal_symbol *msym;
+/* The instruction for a Linux system call is:
+ int $0x80
+ or 0xcd 0x80. */
- ALL_OBJFILE_MSYMBOLS (objfile, msym)
- {
- if (SYMBOL_NAME (msym)
- && STREQ (SYMBOL_NAME (msym), name))
- {
- *objfile_p = objfile;
- return msym;
- }
- }
- }
+static const unsigned char linux_syscall[] = { 0xcd, 0x80 };
- return 0;
-}
+#define LINUX_SYSCALL_LEN (sizeof linux_syscall)
+/* The system call number is stored in the %eax register. */
+#define LINUX_SYSCALL_REGNUM 0 /* %eax */
-static CORE_ADDR
-skip_hurd_resolver (CORE_ADDR pc)
-{
- /* The HURD dynamic linker is part of the GNU C library, so many
- GNU/Linux distributions use it. (All ELF versions, as far as I
- know.) An unresolved PLT entry points to "_dl_runtime_resolve",
- which calls "fixup" to patch the PLT, and then passes control to
- the function.
-
- We look for the symbol `_dl_runtime_resolve', and find `fixup' in
- the same objfile. If we are at the entry point of `fixup', then
- we set a breakpoint at the return address (at the top of the
- stack), and continue.
-
- It's kind of gross to do all these checks every time we're
- called, since they don't change once the executable has gotten
- started. But this is only a temporary hack --- upcoming versions
- of Linux will provide a portable, efficient interface for
- debugging programs that use shared libraries. */
-
- struct objfile *objfile;
- struct minimal_symbol *resolver
- = find_minsym_and_objfile ("_dl_runtime_resolve", &objfile);
-
- if (resolver)
- {
- struct minimal_symbol *fixup
- = lookup_minimal_symbol ("fixup", 0, objfile);
-
- if (fixup && SYMBOL_VALUE_ADDRESS (fixup) == pc)
- return (SAVED_PC_AFTER_CALL (get_current_frame ()));
- }
-
- 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
- a function reference, and
- 2) if so, tells us where to set a temporary breakpoint that will
- trigger when the dynamic linker is done. */
-
-CORE_ADDR
-i386_linux_skip_solib_resolver (CORE_ADDR pc)
-{
- CORE_ADDR result;
-
- /* Plug in functions for other kinds of resolvers here. */
- result = skip_hurd_resolver (pc);
- if (result)
- return result;
-
- return 0;
-}
-
-\f
-/* Recognizing signal handler frames. */
-
-/* Linux has two flavors of signals. Normal signal handlers, and
- "realtime" (RT) signals. The RT signals can provide additional
- information to the signal handler if the SA_SIGINFO flag is set
- when establishing a signal handler using `sigaction'. It is not
- unlikely that future versions of Linux will support SA_SIGINFO for
- normal signals too. */
-
-/* When the i386 Linux kernel calls a signal handler and the
- SA_RESTORER flag isn't set, the return address points to a bit of
- code on the stack. This function returns whether the PC appears to
- be within this bit of code.
-
- The instruction sequence for normal signals is
- pop %eax
- mov $0x77,%eax
- int $0x80
- or 0x58 0xb8 0x77 0x00 0x00 0x00 0xcd 0x80.
-
- Checking for the code sequence should be somewhat reliable, because
- the effect is to call the system call sigreturn. This is unlikely
- to occur anywhere other than a signal trampoline.
-
- It kind of sucks that we have to read memory from the process in
- order to identify a signal trampoline, but there doesn't seem to be
- any other way. The IN_SIGTRAMP macro in tm-linux.h arranges to
- only call us if no function name could be identified, which should
- be the case since the code is on the stack.
-
- Detection of signal trampolines for handlers that set the
- SA_RESTORER flag is in general not possible. Unfortunately this is
- what the GNU C Library has been doing for quite some time now.
- However, as of version 2.1.2, the GNU C Library uses signal
- trampolines (named __restore and __restore_rt) that are identical
- to the ones used by the kernel. Therefore, these trampolines are
- supported too. */
-
-#define LINUX_SIGTRAMP_INSN0 (0x58) /* pop %eax */
-#define LINUX_SIGTRAMP_OFFSET0 (0)
-#define LINUX_SIGTRAMP_INSN1 (0xb8) /* mov $NNNN,%eax */
-#define LINUX_SIGTRAMP_OFFSET1 (1)
-#define LINUX_SIGTRAMP_INSN2 (0xcd) /* int */
-#define LINUX_SIGTRAMP_OFFSET2 (6)
-
-static const unsigned char linux_sigtramp_code[] =
-{
- LINUX_SIGTRAMP_INSN0, /* pop %eax */
- LINUX_SIGTRAMP_INSN1, 0x77, 0x00, 0x00, 0x00, /* mov $0x77,%eax */
- LINUX_SIGTRAMP_INSN2, 0x80 /* int $0x80 */
-};
-
-#define LINUX_SIGTRAMP_LEN (sizeof linux_sigtramp_code)
-
-/* If PC is in a sigtramp routine, return the address of the start of
- the routine. Otherwise, return 0. */
-
-static CORE_ADDR
-i386_linux_sigtramp_start (CORE_ADDR pc)
-{
- unsigned char buf[LINUX_SIGTRAMP_LEN];
-
- /* We only recognize a signal trampoline if PC is at the start of
- one of the three instructions. We optimize for finding the PC at
- the start, as will be the case when the trampoline is not the
- first frame on the stack. We assume that in the case where the
- PC is not at the start of the instruction sequence, there will be
- a few trailing readable bytes on the stack. */
-
- if (read_memory_nobpt (pc, (char *) buf, LINUX_SIGTRAMP_LEN) != 0)
- return 0;
-
- if (buf[0] != LINUX_SIGTRAMP_INSN0)
- {
- int adjust;
-
- switch (buf[0])
- {
- case LINUX_SIGTRAMP_INSN1:
- adjust = LINUX_SIGTRAMP_OFFSET1;
- break;
- case LINUX_SIGTRAMP_INSN2:
- adjust = LINUX_SIGTRAMP_OFFSET2;
- break;
- default:
- return 0;
- }
+/* We are specifically interested in the sigreturn and rt_sigreturn
+ system calls. */
- pc -= adjust;
-
- if (read_memory_nobpt (pc, (char *) buf, LINUX_SIGTRAMP_LEN) != 0)
- return 0;
- }
-
- if (memcmp (buf, linux_sigtramp_code, LINUX_SIGTRAMP_LEN) != 0)
- return 0;
-
- return pc;
-}
-
-/* This function does the same for RT signals. Here the instruction
- sequence is
- mov $0xad,%eax
- int $0x80
- or 0xb8 0xad 0x00 0x00 0x00 0xcd 0x80.
-
- The effect is to call the system call rt_sigreturn. */
-
-#define LINUX_RT_SIGTRAMP_INSN0 (0xb8) /* mov $NNNN,%eax */
-#define LINUX_RT_SIGTRAMP_OFFSET0 (0)
-#define LINUX_RT_SIGTRAMP_INSN1 (0xcd) /* int */
-#define LINUX_RT_SIGTRAMP_OFFSET1 (5)
-
-static const unsigned char linux_rt_sigtramp_code[] =
-{
- LINUX_RT_SIGTRAMP_INSN0, 0xad, 0x00, 0x00, 0x00, /* mov $0xad,%eax */
- LINUX_RT_SIGTRAMP_INSN1, 0x80 /* int $0x80 */
-};
+#ifndef SYS_sigreturn
+#define SYS_sigreturn 0x77
+#endif
+#ifndef SYS_rt_sigreturn
+#define SYS_rt_sigreturn 0xad
+#endif
-#define LINUX_RT_SIGTRAMP_LEN (sizeof linux_rt_sigtramp_code)
+/* Offset to saved processor flags, from <asm/sigcontext.h>. */
+#define LINUX_SIGCONTEXT_EFLAGS_OFFSET (64)
-/* If PC is in a RT sigtramp routine, return the address of the start
- of the routine. Otherwise, return 0. */
+/* Resume execution of the inferior process.
+ If STEP is nonzero, single-step it.
+ If SIGNAL is nonzero, give it that signal. */
-static CORE_ADDR
-i386_linux_rt_sigtramp_start (CORE_ADDR pc)
+void
+child_resume (int pid, int step, enum target_signal signal)
{
- unsigned char buf[LINUX_RT_SIGTRAMP_LEN];
+ int request = PTRACE_CONT;
- /* We only recognize a signal trampoline if PC is at the start of
- one of the two instructions. We optimize for finding the PC at
- the start, as will be the case when the trampoline is not the
- first frame on the stack. We assume that in the case where the
- PC is not at the start of the instruction sequence, there will be
- a few trailing readable bytes on the stack. */
-
- if (read_memory_nobpt (pc, (char *) buf, LINUX_RT_SIGTRAMP_LEN) != 0)
- return 0;
+ 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 (buf[0] != LINUX_RT_SIGTRAMP_INSN0)
+ if (step)
{
- if (buf[0] != LINUX_RT_SIGTRAMP_INSN1)
- return 0;
-
- pc -= LINUX_RT_SIGTRAMP_OFFSET1;
-
- if (read_memory_nobpt (pc, (char *) buf, LINUX_RT_SIGTRAMP_LEN) != 0)
- return 0;
- }
-
- if (memcmp (buf, linux_rt_sigtramp_code, LINUX_RT_SIGTRAMP_LEN) != 0)
- return 0;
-
- return pc;
-}
-
-/* Return whether PC is in a Linux sigtramp routine. */
-
-int
-i386_linux_in_sigtramp (CORE_ADDR pc, char *name)
-{
- if (name)
- return STREQ ("__restore", name) || STREQ ("__restore_rt", name);
-
- return (i386_linux_sigtramp_start (pc) != 0
- || i386_linux_rt_sigtramp_start (pc) != 0);
-}
+ CORE_ADDR pc = read_pc_pid (pid);
+ unsigned char buf[LINUX_SYSCALL_LEN];
-/* Assuming FRAME is for a Linux sigtramp routine, return the address
- of the associated sigcontext structure. */
+ request = PTRACE_SINGLESTEP;
-CORE_ADDR
-i386_linux_sigcontext_addr (struct frame_info *frame)
-{
- CORE_ADDR pc;
+ /* 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. */
- pc = i386_linux_sigtramp_start (frame->pc);
- if (pc)
- {
- CORE_ADDR sp;
-
- if (frame->next)
- /* If this isn't the top frame, the next frame must be for the
- signal handler itself. The sigcontext structure lives on
- the stack, right after the signum argument. */
- return frame->next->frame + 12;
-
- /* This is the top frame. We'll have to find the address of the
- sigcontext structure by looking at the stack pointer. Keep
- in mind that the first instruction of the sigtramp code is
- "pop %eax". If the PC is at this instruction, adjust the
- returned value accordingly. */
- sp = read_register (SP_REGNUM);
- if (pc == frame->pc)
- return sp + 4;
- return sp;
- }
+ /* 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);
- pc = i386_linux_rt_sigtramp_start (frame->pc);
- if (pc)
- {
- if (frame->next)
- /* If this isn't the top frame, the next frame must be for the
- signal handler itself. The sigcontext structure is part of
- the user context. A pointer to the user context is passed
- as the third argument to the signal handler. */
- return read_memory_integer (frame->next->frame + 16, 4) + 20;
-
- /* This is the top frame. Again, use the stack pointer to find
- the address of the sigcontext structure. */
- return read_memory_integer (read_register (SP_REGNUM) + 8, 4) + 20;
+ /* 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);
+ }
+ }
}
- error ("Couldn't recognize signal trampoline.");
- return 0;
+ if (ptrace (request, pid, 0, target_signal_to_host (signal)) == -1)
+ perror_with_name ("ptrace");
}
-
-/* Offset to saved PC in sigcontext, from <asm/sigcontext.h>. */
-#define LINUX_SIGCONTEXT_PC_OFFSET (56)
-
-/* Assuming FRAME is for a Linux sigtramp routine, return the saved
- program counter. */
-
-CORE_ADDR
-i386_linux_sigtramp_saved_pc (struct frame_info *frame)
-{
- CORE_ADDR addr;
- addr = i386_linux_sigcontext_addr (frame);
- return read_memory_integer (addr + LINUX_SIGCONTEXT_PC_OFFSET, 4);
-}
-
-/* Offset to saved SP in sigcontext, from <asm/sigcontext.h>. */
-#define LINUX_SIGCONTEXT_SP_OFFSET (28)
-
-/* Assuming FRAME is for a Linux sigtramp routine, return the saved
- stack pointer. */
-
-CORE_ADDR
-i386_linux_sigtramp_saved_sp (struct frame_info *frame)
-{
- CORE_ADDR addr;
- addr = i386_linux_sigcontext_addr (frame);
- return read_memory_integer (addr + LINUX_SIGCONTEXT_SP_OFFSET, 4);
-}
-
\f
+
/* Register that we are able to handle Linux ELF core file formats. */
static struct core_fns linux_elf_core_fns =
};
void
-_initialize_i386_linux_nat ()
+_initialize_i386_linux_nat (void)
{
add_core_fns (&linux_elf_core_fns);
}