X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=gdb%2Fm68klinux-nat.c;h=82a6124a7aab643be2fcc828272ef86461e4e288;hb=de4112fa387b662c7c7a1dd3e334a1274ca54d28;hp=4eed201fcaf9de7e2632ed6998e8899e659f5667;hpb=ed288bb597072176e84fc8279707a3f2f475779b;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/m68klinux-nat.c b/gdb/m68klinux-nat.c index 4eed201fca..82a6124a7a 100644 --- a/gdb/m68klinux-nat.c +++ b/gdb/m68klinux-nat.c @@ -1,5 +1,7 @@ -/* Motorola m68k native support for Linux - Copyright (C) 1996,1998 Free Software Foundation, Inc. +/* Motorola m68k native support for GNU/Linux. + + Copyright 1996, 1998, 2000, 2001, 2002 Free Software Foundation, + Inc. This file is part of GDB. @@ -23,6 +25,7 @@ #include "inferior.h" #include "language.h" #include "gdbcore.h" +#include "regcache.h" #ifdef USG #include @@ -31,11 +34,16 @@ #include #include #include +#include #include #include #include #include +#ifdef HAVE_SYS_REG_H +#include +#endif + #include #include "gdb_stat.h" @@ -56,20 +64,196 @@ static const int regmap[] = 45, 46, 47 }; +/* Which ptrace request retrieves which registers? + These apply to the corresponding SET requests as well. */ +#define NUM_GREGS (18) +#define MAX_NUM_REGS (NUM_GREGS + 11) + +int +getregs_supplies (int regno) +{ + return 0 <= regno && regno < NUM_GREGS; +} + +int +getfpregs_supplies (int regno) +{ + return FP0_REGNUM <= regno && regno <= FPI_REGNUM; +} + +/* Does the current host support the GETREGS request? */ +int have_ptrace_getregs = +#ifdef HAVE_PTRACE_GETREGS + 1 +#else + 0 +#endif +; + + + /* BLOCKEND is the value of u.u_ar0, and points to the place where GS is stored. */ int -m68k_linux_register_u_addr (blockend, regnum) - int blockend; - int regnum; +m68k_linux_register_u_addr (int blockend, int regnum) { return (blockend + 4 * regmap[regnum]); } + + +/* Fetching registers directly from the U area, one at a time. */ + +/* FIXME: 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. */ + +#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 + +/* Fetch one register. */ + +static void +fetch_register (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_ptid)) == 0) + tid = PIDGET (inferior_ptid); /* 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 (int regno) +{ + if (regno >= 0) + { + fetch_register (regno); + } + else + { + for (regno = 0; regno < NUM_REGS; regno++) + { + fetch_register (regno); + } + } +} + +/* Store one register. */ + +static void +store_register (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; + char *buf = alloca (MAX_REGISTER_RAW_SIZE); + + if (CANNOT_STORE_REGISTER (regno)) + { + return; + } + + /* Overload thread id onto process id */ + if ((tid = TIDGET (inferior_ptid)) == 0) + tid = PIDGET (inferior_ptid); /* no thread id, just use process id */ + + offset = U_REGS_OFFSET; + + regaddr = register_addr (regno, offset); + + /* Put the contents of regno into a local buffer */ + regcache_collect (regno, buf); + + /* Store the local buffer into the inferior a chunk at the time. */ + 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 *) (buf + i)); + regaddr += sizeof (PTRACE_XFER_TYPE); + if (errno != 0) + { + sprintf (mess, "writing register %s (#%d)", + REGISTER_NAME (regno), regno); + perror_with_name (mess); + } + } +} -/* Given a pointer to a general register set in /proc format (gregset_t *), - unpack the register contents and supply them as gdb's idea of the current - register values. */ +/* 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 (int regno) +{ + if (regno >= 0) + { + store_register (regno); + } + else + { + for (regno = 0; regno < NUM_REGS; regno++) + { + store_register (regno); + } + } +} + +/* Given a pointer to a general register set in /proc format + (elf_gregset_t *), unpack the register contents and supply + them as gdb's idea of the current register values. */ /* Note both m68k-tdep.c and m68klinux-nat.c contain definitions @@ -82,75 +266,445 @@ m68k_linux_register_u_addr (blockend, regnum) #ifndef USE_PROC_FS +/* Prototypes for supply_gregset etc. */ +#include "gregset.h" + void -supply_gregset (gregsetp) - gregset_t *gregsetp; +supply_gregset (elf_gregset_t *gregsetp) { + elf_greg_t *regp = (elf_greg_t *) gregsetp; int regi; for (regi = D0_REGNUM; regi <= SP_REGNUM; regi++) - supply_register (regi, (char *) (*gregsetp + regmap[regi])); - supply_register (PS_REGNUM, (char *) (*gregsetp + PT_SR)); - supply_register (PC_REGNUM, (char *) (*gregsetp + PT_PC)); + supply_register (regi, (char *) ®p[regmap[regi]]); + supply_register (PS_REGNUM, (char *) ®p[PT_SR]); + supply_register (PC_REGNUM, (char *) ®p[PT_PC]); +} + +/* 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) +{ + elf_greg_t *regp = (elf_greg_t *) gregsetp; + int i; + + for (i = 0; i < NUM_GREGS; i++) + if ((regno == -1 || regno == i)) + regcache_collect (i, regp + regmap[i]); +} + +#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; + + if (ptrace (PTRACE_GETREGS, tid, 0, (int) ®s) < 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; + } + + perror_with_name ("Couldn't get registers"); + } + + supply_gregset (®s); } -/* Given a pointer to a floating point register set in /proc format - (fpregset_t *), unpack the register contents and supply them as gdb's - idea of the current floating point register values. */ +/* Store all valid general-purpose registers in GDB's register array + into the process/thread specified by TID. */ + +static void +store_regs (int tid, int regno) +{ + elf_gregset_t regs; + + if (ptrace (PTRACE_GETREGS, tid, 0, (int) ®s) < 0) + perror_with_name ("Couldn't get registers"); + + 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, int regno) {} + +#endif + + +/* Transfering floating-point registers between GDB, inferiors and cores. */ + +/* What is the address of fpN within the floating-point register set F? */ +#define FPREG_ADDR(f, n) ((char *) &(f)->fpregs[(n) * 3]) + +/* Fill GDB's register array with the floating-point register values in + *FPREGSETP. */ void -supply_fpregset (fpregsetp) - fpregset_t *fpregsetp; +supply_fpregset (elf_fpregset_t *fpregsetp) { int regi; for (regi = FP0_REGNUM; regi < FPC_REGNUM; regi++) - supply_register (regi, (char *) &fpregsetp->fpregs[(regi - FP0_REGNUM) * 3]); + supply_register (regi, FPREG_ADDR (fpregsetp, regi - FP0_REGNUM)); supply_register (FPC_REGNUM, (char *) &fpregsetp->fpcntl[0]); supply_register (FPS_REGNUM, (char *) &fpregsetp->fpcntl[1]); supply_register (FPI_REGNUM, (char *) &fpregsetp->fpcntl[2]); } +/* 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) +{ + int i; + + /* Fill in the floating-point registers. */ + for (i = FP0_REGNUM; i < FP0_REGNUM + 8; i++) + if (regno == -1 || regno == i) + regcache_collect (regno, FPREG_ADDR (fpregsetp, regno - FP0_REGNUM)); + + /* Fill in the floating-point control registers. */ + for (i = FPC_REGNUM; i <= FPI_REGNUM; i++) + if (regno == -1 || regno == i) + regcache_collect (regno, (char *) &fpregsetp->fpcntl[regno - FPC_REGNUM]); +} + +#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; + + if (ptrace (PTRACE_GETFPREGS, tid, 0, (int) &fpregs) < 0) + perror_with_name ("Couldn't get floating point status"); + + 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, int regno) +{ + elf_fpregset_t fpregs; + + if (ptrace (PTRACE_GETFPREGS, tid, 0, (int) &fpregs) < 0) + perror_with_name ("Couldn't get floating point status"); + + fill_fpregset (&fpregs, regno); + + 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, int regno) {} + +#endif + #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; + } + + /* GNU/Linux LWP ID's are process ID's. */ + if ((tid = TIDGET (inferior_ptid)) == 0) + tid = PIDGET (inferior_ptid); /* Not a threaded program. */ + + /* 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_fpxregs 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; + } + + fetch_fpregs (tid); + return; + } + + if (getregs_supplies (regno)) + { + fetch_regs (tid); + return; + } + + if (getfpregs_supplies (regno)) + { + fetch_fpregs (tid); + return; + } + + internal_error (__FILE__, __LINE__, + "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; + } + + /* GNU/Linux LWP ID's are process ID's. */ + if ((tid = TIDGET (inferior_ptid)) == 0) + tid = PIDGET (inferior_ptid); /* Not a threaded program. */ + + /* Use the PTRACE_SETFPREGS requests whenever possible, since it + transfers more registers in one system call. But remember that + store_fpregs can fail, and return zero. */ + if (regno == -1) + { + store_regs (tid, regno); + store_fpregs (tid, regno); + return; + } + + if (getregs_supplies (regno)) + { + store_regs (tid, regno); + return; + } + + if (getfpregs_supplies (regno)) + { + store_fpregs (tid, regno); + return; + } + + internal_error (__FILE__, __LINE__, + "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 we need to use elf_gregset_t instead of + gregset_t.) + + 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 + + REG_ADDR isn't used on GNU/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; + + 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; + } +} + int -kernel_u_size () +kernel_u_size (void) { return (sizeof (struct user)); } -/* Return non-zero if PC points into the signal trampoline. */ +/* Check whether insn1 and insn2 are parts of a signal trampoline. */ + +#define IS_SIGTRAMP(insn1, insn2) \ + (/* addaw #20,sp; moveq #119,d0; trap #0 */ \ + (insn1 == 0xdefc0014 && insn2 == 0x70774e40) \ + /* moveq #119,d0; trap #0 */ \ + || insn1 == 0x70774e40) + +#define IS_RT_SIGTRAMP(insn1, insn2) \ + (/* movel #173,d0; trap #0 */ \ + (insn1 == 0x203c0000 && insn2 == 0x00ad4e40) \ + /* moveq #82,d0; notb d0; trap #0 */ \ + || (insn1 == 0x70524600 && (insn2 >> 16) == 0x4e40)) + +/* Return non-zero if PC points into the signal trampoline. For the sake + of m68k_linux_frame_saved_pc we also distinguish between non-RT and RT + signal trampolines. */ int -in_sigtramp (pc) - CORE_ADDR pc; +m68k_linux_in_sigtramp (CORE_ADDR pc) { CORE_ADDR sp; - char buf[TARGET_SHORT_BIT / TARGET_CHAR_BIT]; - int insn; + char buf[12]; + unsigned long insn0, insn1, insn2; - sp = read_register (SP_REGNUM); - if (pc - 2 < sp) + if (read_memory_nobpt (pc - 4, buf, sizeof (buf))) return 0; + insn1 = extract_unsigned_integer (buf + 4, 4); + insn2 = extract_unsigned_integer (buf + 8, 4); + if (IS_SIGTRAMP (insn1, insn2)) + return 1; + if (IS_RT_SIGTRAMP (insn1, insn2)) + return 2; - if (read_memory_nobpt (pc, buf, sizeof (buf))) - return 0; - insn = extract_unsigned_integer (buf, sizeof (buf)); - if (insn == 0xdefc /* addaw #,sp */ - || insn == 0x7077 /* moveq #119,d0 */ - || insn == 0x4e40 /* trap #0 */ - || insn == 0x203c /* movel #,d0 */ ) + insn0 = extract_unsigned_integer (buf, 4); + if (IS_SIGTRAMP (insn0, insn1)) return 1; + if (IS_RT_SIGTRAMP (insn0, insn1)) + return 2; - if (read_memory_nobpt (pc - 2, buf, sizeof (buf))) - return 0; - insn = extract_unsigned_integer (buf, sizeof (buf)); - if (insn == 0xdefc /* addaw #,sp */ - || insn == 0x7077 /* moveq #119,d0 */ - || insn == 0x4e40 /* trap #0 */ - || insn == 0x203c /* movel #,d0 */ ) + insn0 = (insn0 << 16) | (insn1 >> 16); + insn1 = (insn1 << 16) | (insn2 >> 16); + if (IS_SIGTRAMP (insn0, insn1)) return 1; + if (IS_RT_SIGTRAMP (insn0, insn1)) + return 2; return 0; } + +/* Offset to saved PC in sigcontext, from . */ +#define SIGCONTEXT_PC_OFFSET 26 + +/* Offset to saved PC in ucontext, from . */ +#define UCONTEXT_PC_OFFSET 88 + +/* Get saved user PC for sigtramp from sigcontext or ucontext. */ + +static CORE_ADDR +m68k_linux_sigtramp_saved_pc (struct frame_info *frame) +{ + CORE_ADDR sigcontext_addr; + char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT]; + int ptrbytes = TARGET_PTR_BIT / TARGET_CHAR_BIT; + int sigcontext_offs = (2 * TARGET_INT_BIT) / TARGET_CHAR_BIT; + + /* Get sigcontext address, it is the third parameter on the stack. */ + if (frame->next) + sigcontext_addr = read_memory_integer (FRAME_ARGS_ADDRESS (frame->next) + + FRAME_ARGS_SKIP + + sigcontext_offs, + ptrbytes); + else + sigcontext_addr = read_memory_integer (read_register (SP_REGNUM) + + sigcontext_offs, + ptrbytes); + + /* Don't cause a memory_error when accessing sigcontext in case the + stack layout has changed or the stack is corrupt. */ + if (m68k_linux_in_sigtramp (frame->pc) == 2) + target_read_memory (sigcontext_addr + UCONTEXT_PC_OFFSET, buf, ptrbytes); + else + target_read_memory (sigcontext_addr + SIGCONTEXT_PC_OFFSET, buf, ptrbytes); + return extract_unsigned_integer (buf, ptrbytes); +} + +/* Return the saved program counter for FRAME. */ + +CORE_ADDR +m68k_linux_frame_saved_pc (struct frame_info *frame) +{ + if (frame->signal_handler_caller) + return m68k_linux_sigtramp_saved_pc (frame); + + return read_memory_integer (frame->frame + 4, 4); +} + +/* Register that we are able to handle GNU/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_m68k_linux_nat () +{ + add_core_fns (&linux_elf_core_fns); +}