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Diffstat (limited to 'gdb/pyr-xdep.c')
| -rw-r--r-- | gdb/pyr-xdep.c | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/gdb/pyr-xdep.c b/gdb/pyr-xdep.c new file mode 100644 index 0000000..5ba4a8d --- /dev/null +++ b/gdb/pyr-xdep.c @@ -0,0 +1,366 @@ +/* Low level Pyramid interface to ptrace, for GDB when running under Unix. + Copyright (C) 1988, 1989, 1991 Free Software Foundation, Inc. + +This file is part of GDB. + +GDB 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 1, or (at your option) +any later version. + +GDB 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 GDB; see the file COPYING. If not, write to +the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#include <stdio.h> +#include "defs.h" +#include "param.h" +#include "frame.h" +#include "inferior.h" + +#include <sys/param.h> +#include <sys/dir.h> +#include <signal.h> +#include <sys/ioctl.h> +/* #include <fcntl.h> Can we live without this? */ + +#include "gdbcore.h" +#include <sys/user.h> /* After a.out.h */ +#include <sys/file.h> +#include <sys/stat.h> + +void +fetch_inferior_registers () +{ + register int regno, datum; + register unsigned int regaddr; + int reg_buf[NUM_REGS+1]; + struct user u; + register int skipped_frames = 0; + + registers_fetched (); + + for (regno = 0; regno < 64; regno++) { + reg_buf[regno] = ptrace (3, inferior_pid, regno, 0); + +#if defined(PYRAMID_CONTROL_FRAME_DEBUGGING) + printf ("Fetching %s from inferior, got %0x\n", + reg_names[regno], + reg_buf[regno]); +#endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */ + + if (reg_buf[regno] == -1 && errno == EIO) { + printf("fetch_interior_registers: fetching %s from inferior\n", + reg_names[regno]); + errno = 0; + } + supply_register (regno, reg_buf+regno); + } + /* that leaves regs 64, 65, and 66 */ + datum = ptrace (3, inferior_pid, + ((char *)&u.u_pcb.pcb_csp) - + ((char *)&u), 0); + + + + /* FIXME: Find the Current Frame Pointer (CFP). CFP is a global + register (ie, NOT windowed), that gets saved in a frame iff + the code for that frame has a prologue (ie, "adsf N"). If + there is a prologue, the adsf insn saves the old cfp in + pr13, cfp is set to sp, and N bytes of locals are allocated + (sp is decremented by n). + This makes finding CFP hard. I guess the right way to do it + is: + - If this is the innermost frame, believe ptrace() or + the core area. + - Otherwise: + Find the first insn of the current frame. + - find the saved pc; + - find the call insn that saved it; + - figure out where the call is to; + - if the first insn is an adsf, we got a frame + pointer. */ + + + /* Normal processors have separate stack pointers for user and + kernel mode. Getting the last user mode frame on such + machines is easy: the kernel context of the ptrace()'d + process is on the kernel stack, and the USP points to what + we want. But Pyramids only have a single cfp for both user and + kernel mode. And processes being ptrace()'d have some + kernel-context control frames on their stack. + To avoid tracing back into the kernel context of an inferior, + we skip 0 or more contiguous control frames where the pc is + in the kernel. */ + + while (1) { + register int inferior_saved_pc; + inferior_saved_pc = ptrace (1, inferior_pid, datum+((32+15)*4), 0); + if (inferior_saved_pc > 0) break; +#if defined(PYRAMID_CONTROL_FRAME_DEBUGGING) + printf("skipping kernel frame %08x, pc=%08x\n", datum, + inferior_saved_pc); +#endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */ + skipped_frames++; + datum -= CONTROL_STACK_FRAME_SIZE; + } + + reg_buf[CSP_REGNUM] = datum; + supply_register(CSP_REGNUM, reg_buf+CSP_REGNUM); +#ifdef PYRAMID_CONTROL_FRAME_DEBUGGING + if (skipped_frames) { + fprintf (stderr, + "skipped %d frames from %x to %x; cfp was %x, now %x\n", + skipped_frames, reg_buf[CSP_REGNUM]); + } +#endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */ +} + +/* Store our register values back into the inferior. + If REGNO is -1, do this for all registers. + Otherwise, REGNO specifies which register (so we can save time). */ + +store_inferior_registers (regno) + int regno; +{ + register unsigned int regaddr; + char buf[80]; + + if (regno >= 0) + { + if ((0 <= regno) && (regno < 64)) { + /*regaddr = register_addr (regno, offset);*/ + regaddr = regno; + errno = 0; + ptrace (6, inferior_pid, regaddr, read_register (regno)); + if (errno != 0) + { + sprintf (buf, "writing register number %d", regno); + perror_with_name (buf); + } + } + } + else + { + for (regno = 0; regno < NUM_REGS; regno++) + { + /*regaddr = register_addr (regno, offset);*/ + regaddr = regno; + errno = 0; + ptrace (6, inferior_pid, regaddr, read_register (regno)); + if (errno != 0) + { + sprintf (buf, "writing all regs, number %d", regno); + perror_with_name (buf); + } + } +} + +/*** Extensions to core and dump files, for GDB. */ + +extern unsigned int last_frame_offset; + +#ifdef PYRAMID_CORE + +/* Can't make definitions here static, since core.c needs them + to do bounds checking on the core-file areas. O well. */ + +/* have two stacks: one for data, one for register windows. */ +extern CORE_ADDR reg_stack_start; +extern CORE_ADDR reg_stack_end; + +/* need this so we can find the global registers: they never get saved. */ +CORE_ADDR global_reg_offset; +static CORE_ADDR last_frame_address; +CORE_ADDR last_frame_offset; + + +/* Address in core file of start of register window stack area. + Don't know if is this any of meaningful, useful or necessary. */ +extern int reg_stack_offset; + +#endif /* PYRAMID_CORE */ + + +/* Work with core dump and executable files, for GDB. + This code would be in core.c if it weren't machine-dependent. */ + +void +core_file_command (filename, from_tty) + char *filename; + int from_tty; +{ + int val; + extern char registers[]; + + /* Discard all vestiges of any previous core file + and mark data and stack spaces as empty. */ + + if (corefile) + free (corefile); + corefile = 0; + + if (corechan >= 0) + close (corechan); + corechan = -1; + + data_start = 0; + data_end = 0; + stack_start = STACK_END_ADDR; + stack_end = STACK_END_ADDR; + +#ifdef PYRAMID_CORE + reg_stack_start = CONTROL_STACK_ADDR; + reg_stack_end = CONTROL_STACK_ADDR; /* this isn't strictly true...*/ +#endif /* PYRAMID_CORE */ + + /* Now, if a new core file was specified, open it and digest it. */ + + if (filename) + { + filename = tilde_expand (filename); + make_cleanup (free, filename); + + if (have_inferior_p ()) + error ("To look at a core file, you must kill the inferior with \"kill\"."); + corechan = open (filename, O_RDONLY, 0); + if (corechan < 0) + perror_with_name (filename); + /* 4.2-style (and perhaps also sysV-style) core dump file. */ + { + struct user u; + + unsigned int reg_offset; + + val = myread (corechan, &u, sizeof u); + if (val < 0) + perror_with_name ("Not a core file: reading upage"); + if (val != sizeof u) + error ("Not a core file: could only read %d bytes", val); + data_start = exec_data_start; + + data_end = data_start + NBPG * u.u_dsize; + data_offset = NBPG * UPAGES; + stack_offset = NBPG * (UPAGES + u.u_dsize); + + /* find registers in core file */ +#ifdef PYRAMID_PTRACE + stack_start = stack_end - NBPG * u.u_ussize; + reg_stack_offset = stack_offset + (NBPG *u.u_ussize); + reg_stack_end = reg_stack_start + NBPG * u.u_cssize; + + last_frame_address = ((int) u.u_pcb.pcb_csp); + last_frame_offset = reg_stack_offset + last_frame_address + - CONTROL_STACK_ADDR ; + global_reg_offset = (char *)&u - (char *)&u.u_pcb.pcb_gr0 ; + + /* skip any control-stack frames that were executed in the + kernel. */ + + while (1) { + char buf[4]; + val = lseek (corechan, last_frame_offset+(47*4), 0); + if (val < 0) + perror_with_name (filename); + val = myread (corechan, buf, sizeof buf); + if (val < 0) + perror_with_name (filename); + + if (*(int *)buf >= 0) + break; + printf ("skipping frame %0x\n", last_frame_address); + last_frame_offset -= CONTROL_STACK_FRAME_SIZE; + last_frame_address -= CONTROL_STACK_FRAME_SIZE; + } + reg_offset = last_frame_offset; + +#if 1 || defined(PYRAMID_CONTROL_FRAME_DEBUGGING) + printf ("Control stack pointer = 0x%08x\n", + u.u_pcb.pcb_csp); + printf ("offset to control stack %d outermost frame %d (%0x)\n", + reg_stack_offset, reg_offset, last_frame_address); +#endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */ + +#else /* not PYRAMID_CORE */ + stack_start = stack_end - NBPG * u.u_ssize; + reg_offset = (int) u.u_ar0 - KERNEL_U_ADDR; +#endif /* not PYRAMID_CORE */ + +#ifdef __not_on_pyr_yet + /* Some machines put an absolute address in here and some put + the offset in the upage of the regs. */ + reg_offset = (int) u.u_ar0; + if (reg_offset > NBPG * UPAGES) + reg_offset -= KERNEL_U_ADDR; +#endif + + /* I don't know where to find this info. + So, for now, mark it as not available. */ + N_SET_MAGIC (core_aouthdr, 0); + + /* Read the register values out of the core file and store + them where `read_register' will find them. */ + + { + register int regno; + + for (regno = 0; regno < 64; regno++) + { + char buf[MAX_REGISTER_RAW_SIZE]; + + val = lseek (corechan, register_addr (regno, reg_offset), 0); + if (val < 0 + || (val = myread (corechan, buf, sizeof buf)) < 0) + { + char * buffer = (char *) alloca (strlen (reg_names[regno]) + + 30); + strcpy (buffer, "Reading register "); + strcat (buffer, reg_names[regno]); + + perror_with_name (buffer); + } + + if (val < 0) + perror_with_name (filename); +#ifdef PYRAMID_CONTROL_FRAME_DEBUGGING + printf ("[reg %s(%d), offset in file %s=0x%0x, addr =0x%0x, =%0x]\n", + reg_names[regno], regno, filename, + register_addr(regno, reg_offset), + regno * 4 + last_frame_address, + *((int *)buf)); +#endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */ + supply_register (regno, buf); + } + } + } + if (filename[0] == '/') + corefile = savestring (filename, strlen (filename)); + else + { + corefile = concat (current_directory, "/", filename); + } + +#if 1 || defined(PYRAMID_CONTROL_FRAME_DEBUGGING) + printf ("Providing CSP (%0x) as nominal address of current frame.\n", + last_frame_address); +#endif PYRAMID_CONTROL_FRAME_DEBUGGING + /* FIXME: Which of the following is correct? */ +#if 0 + set_current_frame ( create_new_frame (read_register (FP_REGNUM), + read_pc ())); +#else + set_current_frame ( create_new_frame (last_frame_address, + read_pc ())); +#endif + + select_frame (get_current_frame (), 0); + validate_files (); + } + else if (from_tty) + printf ("No core file now.\n"); +} |