| /* 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 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. |
| |
| 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. */ |
| #include "symtab.h" |
| #include "symfile.h" |
| #include "objfiles.h" |
| |
| #include <sys/ptrace.h> |
| #include <sys/user.h> |
| #include <sys/procfs.h> |
| |
| #ifdef HAVE_SYS_REG_H |
| #include <sys/reg.h> |
| #endif |
| |
| /* Prototypes for supply_gregset etc. */ |
| #include "gregset.h" |
| |
| /* 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 |
| }; |
| |
| /* 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 |
| ; |
| |
| |
| /* 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. */ |
| |
| #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 |
| |
| /* 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). */ |
| |
| void |
| old_fetch_inferior_registers (regno) |
| int regno; |
| { |
| if (regno >= 0) |
| { |
| fetch_register (regno); |
| } |
| else |
| { |
| for (regno = 0; regno < ARCH_NUM_REGS; regno++) |
| { |
| fetch_register (regno); |
| } |
| } |
| } |
| |
| /* 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)) |
| { |
| 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); |
| } |
| } |
| } |
| |
| /* 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 |
| 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); |
| } |
| } |
| } |
| |
| |
| /* 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; |
| |
| 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 (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; |
| |
| 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 |
| |
| |
| /* 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) |
| |
| /* 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)); |
| } |
| |
| /* 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 (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); |
| } |
| } |
| |
| #ifdef HAVE_PTRACE_GETREGS |
| |
| /* Fetch all floating-point registers from process/thread TID and store |
| thier values in GDB's register array. */ |
| |
| static void |
| 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; |
| } |
| |
| supply_fpregset (&fpregs); |
| } |
| |
| /* Store all valid floating-point registers in GDB's register array |
| into the process/thread specified by TID. */ |
| |
| static void |
| store_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; |
| } |
| |
| convert_to_fpregset (&fpregs, register_valid); |
| |
| ret = ptrace (PTRACE_SETFPREGS, tid, 0, (int) &fpregs); |
| if (ret < 0) |
| { |
| warning ("Couldn't write floating point status."); |
| return; |
| } |
| } |
| |
| #else |
| |
| static void fetch_fpregs (int tid) {} |
| static void store_fpregs (int tid) {} |
| |
| #endif |
| |
| |
| /* 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. */ |
| |
| static void |
| supply_xfpregset (struct user_xfpregs_struct *xfpregs) |
| { |
| 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); |
| } |
| |
| /* 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. */ |
| |
| static void |
| convert_to_xfpregset (struct user_xfpregs_struct *xfpregs, |
| signed char *valid) |
| { |
| 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)); |
| } |
| |
| /* 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) |
| { |
| if (errno == EIO) |
| { |
| have_ptrace_getxfpregs = 0; |
| return 0; |
| } |
| |
| warning ("Couldn't read floating-point and SSE registers."); |
| return 0; |
| } |
| |
| supply_xfpregset (&xfpregs); |
| return 1; |
| } |
| |
| /* 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) |
| { |
| 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 |
| |
| /* 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 |
| |
| |
| /* 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) |
| { |
| 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; |
| } |
| |
| /* 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); |
| } |
| |
| |
| /* 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.) |
| |
| 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; |
| } |
| } |
| |
| |
| /* 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 |
| child_resume (int pid, int step, enum target_signal signal) |
| { |
| 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 (ptrace (request, pid, 0, target_signal_to_host (signal)) == -1) |
| perror_with_name ("ptrace"); |
| } |
| |
| |
| /* 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; |
| |
| ALL_OBJFILE_MSYMBOLS (objfile, msym) |
| { |
| if (SYMBOL_NAME (msym) |
| && STREQ (SYMBOL_NAME (msym), name)) |
| { |
| *objfile_p = objfile; |
| return msym; |
| } |
| } |
| } |
| |
| return 0; |
| } |
| |
| |
| 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; |
| } |
| |
| |
| /* 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); |
| } |