/* Native support code for PPC AIX, for GDB the GNU debugger. Copyright (C) 2006-2019 Free Software Foundation, Inc. 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 3 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, see . */ #include "defs.h" #include "osabi.h" #include "regcache.h" #include "regset.h" #include "gdbtypes.h" #include "gdbcore.h" #include "target.h" #include "value.h" #include "infcall.h" #include "objfiles.h" #include "breakpoint.h" #include "rs6000-tdep.h" #include "ppc-tdep.h" #include "rs6000-aix-tdep.h" #include "xcoffread.h" #include "solib.h" #include "solib-aix.h" #include "target-float.h" #include "gdbsupport/xml-utils.h" #include "trad-frame.h" #include "frame-unwind.h" /* If the kernel has to deliver a signal, it pushes a sigcontext structure on the stack and then calls the signal handler, passing the address of the sigcontext in an argument register. Usually the signal handler doesn't save this register, so we have to access the sigcontext structure via an offset from the signal handler frame. The following constants were determined by experimentation on AIX 3.2. sigcontext structure have the mstsave saved under the sc_jmpbuf.jmp_context. STKMIN(minimum stack size) is 56 for 32-bit processes, and iar offset under sc_jmpbuf.jmp_context is 40. ie offsetof(struct sigcontext, sc_jmpbuf.jmp_context.iar). so PC offset in this case is STKMIN+iar offset, which is 96. */ #define SIG_FRAME_PC_OFFSET 96 #define SIG_FRAME_LR_OFFSET 108 /* STKMIN+grp1 offset, which is 56+228=284 */ #define SIG_FRAME_FP_OFFSET 284 /* 64 bit process. STKMIN64 is 112 and iar offset is 312. So 112+312=424 */ #define SIG_FRAME_LR_OFFSET64 424 /* STKMIN64+grp1 offset. 112+56=168 */ #define SIG_FRAME_FP_OFFSET64 168 static struct trad_frame_cache * aix_sighandle_frame_cache (struct frame_info *this_frame, void **this_cache) { LONGEST backchain; CORE_ADDR base, base_orig, func; struct gdbarch *gdbarch = get_frame_arch (this_frame); struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); struct trad_frame_cache *this_trad_cache; if ((*this_cache) != NULL) return (struct trad_frame_cache *) (*this_cache); this_trad_cache = trad_frame_cache_zalloc (this_frame); (*this_cache) = this_trad_cache; base = get_frame_register_unsigned (this_frame, gdbarch_sp_regnum (gdbarch)); base_orig = base; if (tdep->wordsize == 4) { func = read_memory_unsigned_integer (base_orig + SIG_FRAME_PC_OFFSET + 8, tdep->wordsize, byte_order); safe_read_memory_integer (base_orig + SIG_FRAME_FP_OFFSET + 8, tdep->wordsize, byte_order, &backchain); base = (CORE_ADDR)backchain; } else { func = read_memory_unsigned_integer (base_orig + SIG_FRAME_LR_OFFSET64, tdep->wordsize, byte_order); safe_read_memory_integer (base_orig + SIG_FRAME_FP_OFFSET64, tdep->wordsize, byte_order, &backchain); base = (CORE_ADDR)backchain; } trad_frame_set_reg_value (this_trad_cache, gdbarch_pc_regnum (gdbarch), func); trad_frame_set_reg_value (this_trad_cache, gdbarch_sp_regnum (gdbarch), base); if (tdep->wordsize == 4) trad_frame_set_reg_addr (this_trad_cache, tdep->ppc_lr_regnum, base_orig + 0x38 + 52 + 8); else trad_frame_set_reg_addr (this_trad_cache, tdep->ppc_lr_regnum, base_orig + 0x70 + 320); trad_frame_set_id (this_trad_cache, frame_id_build (base, func)); trad_frame_set_this_base (this_trad_cache, base); return this_trad_cache; } static void aix_sighandle_frame_this_id (struct frame_info *this_frame, void **this_prologue_cache, struct frame_id *this_id) { struct trad_frame_cache *this_trad_cache = aix_sighandle_frame_cache (this_frame, this_prologue_cache); trad_frame_get_id (this_trad_cache, this_id); } static struct value * aix_sighandle_frame_prev_register (struct frame_info *this_frame, void **this_prologue_cache, int regnum) { struct trad_frame_cache *this_trad_cache = aix_sighandle_frame_cache (this_frame, this_prologue_cache); return trad_frame_get_register (this_trad_cache, this_frame, regnum); } int aix_sighandle_frame_sniffer (const struct frame_unwind *self, struct frame_info *this_frame, void **this_prologue_cache) { CORE_ADDR pc = get_frame_pc (this_frame); if (pc && pc < AIX_TEXT_SEGMENT_BASE) return 1; return 0; } /* AIX signal handler frame unwinder */ static const struct frame_unwind aix_sighandle_frame_unwind = { SIGTRAMP_FRAME, default_frame_unwind_stop_reason, aix_sighandle_frame_this_id, aix_sighandle_frame_prev_register, NULL, aix_sighandle_frame_sniffer }; /* Core file support. */ static struct ppc_reg_offsets rs6000_aix32_reg_offsets = { /* General-purpose registers. */ 208, /* r0_offset */ 4, /* gpr_size */ 4, /* xr_size */ 24, /* pc_offset */ 28, /* ps_offset */ 32, /* cr_offset */ 36, /* lr_offset */ 40, /* ctr_offset */ 44, /* xer_offset */ 48, /* mq_offset */ /* Floating-point registers. */ 336, /* f0_offset */ 56, /* fpscr_offset */ 4 /* fpscr_size */ }; static struct ppc_reg_offsets rs6000_aix64_reg_offsets = { /* General-purpose registers. */ 0, /* r0_offset */ 8, /* gpr_size */ 4, /* xr_size */ 264, /* pc_offset */ 256, /* ps_offset */ 288, /* cr_offset */ 272, /* lr_offset */ 280, /* ctr_offset */ 292, /* xer_offset */ -1, /* mq_offset */ /* Floating-point registers. */ 312, /* f0_offset */ 296, /* fpscr_offset */ 4 /* fpscr_size */ }; /* Supply register REGNUM in the general-purpose register set REGSET from the buffer specified by GREGS and LEN to register cache REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */ static void rs6000_aix_supply_regset (const struct regset *regset, struct regcache *regcache, int regnum, const void *gregs, size_t len) { ppc_supply_gregset (regset, regcache, regnum, gregs, len); ppc_supply_fpregset (regset, regcache, regnum, gregs, len); } /* Collect register REGNUM in the general-purpose register set REGSET, from register cache REGCACHE into the buffer specified by GREGS and LEN. If REGNUM is -1, do this for all registers in REGSET. */ static void rs6000_aix_collect_regset (const struct regset *regset, const struct regcache *regcache, int regnum, void *gregs, size_t len) { ppc_collect_gregset (regset, regcache, regnum, gregs, len); ppc_collect_fpregset (regset, regcache, regnum, gregs, len); } /* AIX register set. */ static const struct regset rs6000_aix32_regset = { &rs6000_aix32_reg_offsets, rs6000_aix_supply_regset, rs6000_aix_collect_regset, }; static const struct regset rs6000_aix64_regset = { &rs6000_aix64_reg_offsets, rs6000_aix_supply_regset, rs6000_aix_collect_regset, }; /* Iterate over core file register note sections. */ static void rs6000_aix_iterate_over_regset_sections (struct gdbarch *gdbarch, iterate_over_regset_sections_cb *cb, void *cb_data, const struct regcache *regcache) { if (gdbarch_tdep (gdbarch)->wordsize == 4) cb (".reg", 592, 592, &rs6000_aix32_regset, NULL, cb_data); else cb (".reg", 576, 576, &rs6000_aix64_regset, NULL, cb_data); } /* Pass the arguments in either registers, or in the stack. In RS/6000, the first eight words of the argument list (that might be less than eight parameters if some parameters occupy more than one word) are passed in r3..r10 registers. Float and double parameters are passed in fpr's, in addition to that. Rest of the parameters if any are passed in user stack. There might be cases in which half of the parameter is copied into registers, the other half is pushed into stack. Stack must be aligned on 64-bit boundaries when synthesizing function calls. If the function is returning a structure, then the return address is passed in r3, then the first 7 words of the parameters can be passed in registers, starting from r4. */ static CORE_ADDR rs6000_push_dummy_call (struct gdbarch *gdbarch, struct value *function, struct regcache *regcache, CORE_ADDR bp_addr, int nargs, struct value **args, CORE_ADDR sp, function_call_return_method return_method, CORE_ADDR struct_addr) { struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); int ii; int len = 0; int argno; /* current argument number */ int argbytes; /* current argument byte */ gdb_byte tmp_buffer[50]; int f_argno = 0; /* current floating point argno */ int wordsize = gdbarch_tdep (gdbarch)->wordsize; CORE_ADDR func_addr = find_function_addr (function, NULL); struct value *arg = 0; struct type *type; ULONGEST saved_sp; /* The calling convention this function implements assumes the processor has floating-point registers. We shouldn't be using it on PPC variants that lack them. */ gdb_assert (ppc_floating_point_unit_p (gdbarch)); /* The first eight words of ther arguments are passed in registers. Copy them appropriately. */ ii = 0; /* If the function is returning a `struct', then the first word (which will be passed in r3) is used for struct return address. In that case we should advance one word and start from r4 register to copy parameters. */ if (return_method == return_method_struct) { regcache_raw_write_unsigned (regcache, tdep->ppc_gp0_regnum + 3, struct_addr); ii++; } /* effectively indirect call... gcc does... return_val example( float, int); eabi: float in fp0, int in r3 offset of stack on overflow 8/16 for varargs, must go by type. power open: float in r3&r4, int in r5 offset of stack on overflow different both: return in r3 or f0. If no float, must study how gcc emulates floats; pay attention to arg promotion. User may have to cast\args to handle promotion correctly since gdb won't know if prototype supplied or not. */ for (argno = 0, argbytes = 0; argno < nargs && ii < 8; ++ii) { int reg_size = register_size (gdbarch, ii + 3); arg = args[argno]; type = check_typedef (value_type (arg)); len = TYPE_LENGTH (type); if (TYPE_CODE (type) == TYPE_CODE_FLT) { /* Floating point arguments are passed in fpr's, as well as gpr's. There are 13 fpr's reserved for passing parameters. At this point there is no way we would run out of them. Always store the floating point value using the register's floating-point format. */ const int fp_regnum = tdep->ppc_fp0_regnum + 1 + f_argno; gdb_byte reg_val[PPC_MAX_REGISTER_SIZE]; struct type *reg_type = register_type (gdbarch, fp_regnum); gdb_assert (len <= 8); target_float_convert (value_contents (arg), type, reg_val, reg_type); regcache->cooked_write (fp_regnum, reg_val); ++f_argno; } if (len > reg_size) { /* Argument takes more than one register. */ while (argbytes < len) { gdb_byte word[PPC_MAX_REGISTER_SIZE]; memset (word, 0, reg_size); memcpy (word, ((char *) value_contents (arg)) + argbytes, (len - argbytes) > reg_size ? reg_size : len - argbytes); regcache->cooked_write (tdep->ppc_gp0_regnum + 3 + ii, word); ++ii, argbytes += reg_size; if (ii >= 8) goto ran_out_of_registers_for_arguments; } argbytes = 0; --ii; } else { /* Argument can fit in one register. No problem. */ gdb_byte word[PPC_MAX_REGISTER_SIZE]; memset (word, 0, reg_size); memcpy (word, value_contents (arg), len); regcache->cooked_write (tdep->ppc_gp0_regnum + 3 +ii, word); } ++argno; } ran_out_of_registers_for_arguments: regcache_cooked_read_unsigned (regcache, gdbarch_sp_regnum (gdbarch), &saved_sp); /* Location for 8 parameters are always reserved. */ sp -= wordsize * 8; /* Another six words for back chain, TOC register, link register, etc. */ sp -= wordsize * 6; /* Stack pointer must be quadword aligned. */ sp &= -16; /* If there are more arguments, allocate space for them in the stack, then push them starting from the ninth one. */ if ((argno < nargs) || argbytes) { int space = 0, jj; if (argbytes) { space += ((len - argbytes + 3) & -4); jj = argno + 1; } else jj = argno; for (; jj < nargs; ++jj) { struct value *val = args[jj]; space += ((TYPE_LENGTH (value_type (val))) + 3) & -4; } /* Add location required for the rest of the parameters. */ space = (space + 15) & -16; sp -= space; /* This is another instance we need to be concerned about securing our stack space. If we write anything underneath %sp (r1), we might conflict with the kernel who thinks he is free to use this area. So, update %sp first before doing anything else. */ regcache_raw_write_signed (regcache, gdbarch_sp_regnum (gdbarch), sp); /* If the last argument copied into the registers didn't fit there completely, push the rest of it into stack. */ if (argbytes) { write_memory (sp + 24 + (ii * 4), value_contents (arg) + argbytes, len - argbytes); ++argno; ii += ((len - argbytes + 3) & -4) / 4; } /* Push the rest of the arguments into stack. */ for (; argno < nargs; ++argno) { arg = args[argno]; type = check_typedef (value_type (arg)); len = TYPE_LENGTH (type); /* Float types should be passed in fpr's, as well as in the stack. */ if (TYPE_CODE (type) == TYPE_CODE_FLT && f_argno < 13) { gdb_assert (len <= 8); regcache->cooked_write (tdep->ppc_fp0_regnum + 1 + f_argno, value_contents (arg)); ++f_argno; } write_memory (sp + 24 + (ii * 4), value_contents (arg), len); ii += ((len + 3) & -4) / 4; } } /* Set the stack pointer. According to the ABI, the SP is meant to be set _before_ the corresponding stack space is used. On AIX, this even applies when the target has been completely stopped! Not doing this can lead to conflicts with the kernel which thinks that it still has control over this not-yet-allocated stack region. */ regcache_raw_write_signed (regcache, gdbarch_sp_regnum (gdbarch), sp); /* Set back chain properly. */ store_unsigned_integer (tmp_buffer, wordsize, byte_order, saved_sp); write_memory (sp, tmp_buffer, wordsize); /* Point the inferior function call's return address at the dummy's breakpoint. */ regcache_raw_write_signed (regcache, tdep->ppc_lr_regnum, bp_addr); /* Set the TOC register value. */ regcache_raw_write_signed (regcache, tdep->ppc_toc_regnum, solib_aix_get_toc_value (func_addr)); target_store_registers (regcache, -1); return sp; } static enum return_value_convention rs6000_return_value (struct gdbarch *gdbarch, struct value *function, struct type *valtype, struct regcache *regcache, gdb_byte *readbuf, const gdb_byte *writebuf) { struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); /* The calling convention this function implements assumes the processor has floating-point registers. We shouldn't be using it on PowerPC variants that lack them. */ gdb_assert (ppc_floating_point_unit_p (gdbarch)); /* AltiVec extension: Functions that declare a vector data type as a return value place that return value in VR2. */ if (TYPE_CODE (valtype) == TYPE_CODE_ARRAY && TYPE_VECTOR (valtype) && TYPE_LENGTH (valtype) == 16) { if (readbuf) regcache->cooked_read (tdep->ppc_vr0_regnum + 2, readbuf); if (writebuf) regcache->cooked_write (tdep->ppc_vr0_regnum + 2, writebuf); return RETURN_VALUE_REGISTER_CONVENTION; } /* If the called subprogram returns an aggregate, there exists an implicit first argument, whose value is the address of a caller- allocated buffer into which the callee is assumed to store its return value. All explicit parameters are appropriately relabeled. */ if (TYPE_CODE (valtype) == TYPE_CODE_STRUCT || TYPE_CODE (valtype) == TYPE_CODE_UNION || TYPE_CODE (valtype) == TYPE_CODE_ARRAY) return RETURN_VALUE_STRUCT_CONVENTION; /* Scalar floating-point values are returned in FPR1 for float or double, and in FPR1:FPR2 for quadword precision. Fortran complex*8 and complex*16 are returned in FPR1:FPR2, and complex*32 is returned in FPR1:FPR4. */ if (TYPE_CODE (valtype) == TYPE_CODE_FLT && (TYPE_LENGTH (valtype) == 4 || TYPE_LENGTH (valtype) == 8)) { struct type *regtype = register_type (gdbarch, tdep->ppc_fp0_regnum); gdb_byte regval[8]; /* FIXME: kettenis/2007-01-01: Add support for quadword precision and complex. */ if (readbuf) { regcache->cooked_read (tdep->ppc_fp0_regnum + 1, regval); target_float_convert (regval, regtype, readbuf, valtype); } if (writebuf) { target_float_convert (writebuf, valtype, regval, regtype); regcache->cooked_write (tdep->ppc_fp0_regnum + 1, regval); } return RETURN_VALUE_REGISTER_CONVENTION; } /* Values of the types int, long, short, pointer, and char (length is less than or equal to four bytes), as well as bit values of lengths less than or equal to 32 bits, must be returned right justified in GPR3 with signed values sign extended and unsigned values zero extended, as necessary. */ if (TYPE_LENGTH (valtype) <= tdep->wordsize) { if (readbuf) { ULONGEST regval; /* For reading we don't have to worry about sign extension. */ regcache_cooked_read_unsigned (regcache, tdep->ppc_gp0_regnum + 3, ®val); store_unsigned_integer (readbuf, TYPE_LENGTH (valtype), byte_order, regval); } if (writebuf) { /* For writing, use unpack_long since that should handle any required sign extension. */ regcache_cooked_write_unsigned (regcache, tdep->ppc_gp0_regnum + 3, unpack_long (valtype, writebuf)); } return RETURN_VALUE_REGISTER_CONVENTION; } /* Eight-byte non-floating-point scalar values must be returned in GPR3:GPR4. */ if (TYPE_LENGTH (valtype) == 8) { gdb_assert (TYPE_CODE (valtype) != TYPE_CODE_FLT); gdb_assert (tdep->wordsize == 4); if (readbuf) { gdb_byte regval[8]; regcache->cooked_read (tdep->ppc_gp0_regnum + 3, regval); regcache->cooked_read (tdep->ppc_gp0_regnum + 4, regval + 4); memcpy (readbuf, regval, 8); } if (writebuf) { regcache->cooked_write (tdep->ppc_gp0_regnum + 3, writebuf); regcache->cooked_write (tdep->ppc_gp0_regnum + 4, writebuf + 4); } return RETURN_VALUE_REGISTER_CONVENTION; } return RETURN_VALUE_STRUCT_CONVENTION; } /* Support for CONVERT_FROM_FUNC_PTR_ADDR (ARCH, ADDR, TARG). Usually a function pointer's representation is simply the address of the function. On the RS/6000 however, a function pointer is represented by a pointer to an OPD entry. This OPD entry contains three words, the first word is the address of the function, the second word is the TOC pointer (r2), and the third word is the static chain value. Throughout GDB it is currently assumed that a function pointer contains the address of the function, which is not easy to fix. In addition, the conversion of a function address to a function pointer would require allocation of an OPD entry in the inferior's memory space, with all its drawbacks. To be able to call C++ virtual methods in the inferior (which are called via function pointers), find_function_addr uses this function to get the function address from a function pointer. */ /* Return real function address if ADDR (a function pointer) is in the data space and is therefore a special function pointer. */ static CORE_ADDR rs6000_convert_from_func_ptr_addr (struct gdbarch *gdbarch, CORE_ADDR addr, struct target_ops *targ) { struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); struct obj_section *s; s = find_pc_section (addr); /* Normally, functions live inside a section that is executable. So, if ADDR points to a non-executable section, then treat it as a function descriptor and return the target address iff the target address itself points to a section that is executable. */ if (s && (s->the_bfd_section->flags & SEC_CODE) == 0) { CORE_ADDR pc = 0; struct obj_section *pc_section; try { pc = read_memory_unsigned_integer (addr, tdep->wordsize, byte_order); } catch (const gdb_exception_error &e) { /* An error occured during reading. Probably a memory error due to the section not being loaded yet. This address cannot be a function descriptor. */ return addr; } pc_section = find_pc_section (pc); if (pc_section && (pc_section->the_bfd_section->flags & SEC_CODE)) return pc; } return addr; } /* Calculate the destination of a branch/jump. Return -1 if not a branch. */ static CORE_ADDR branch_dest (struct regcache *regcache, int opcode, int instr, CORE_ADDR pc, CORE_ADDR safety) { struct gdbarch *gdbarch = regcache->arch (); struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); CORE_ADDR dest; int immediate; int absolute; int ext_op; absolute = (int) ((instr >> 1) & 1); switch (opcode) { case 18: immediate = ((instr & ~3) << 6) >> 6; /* br unconditional */ if (absolute) dest = immediate; else dest = pc + immediate; break; case 16: immediate = ((instr & ~3) << 16) >> 16; /* br conditional */ if (absolute) dest = immediate; else dest = pc + immediate; break; case 19: ext_op = (instr >> 1) & 0x3ff; if (ext_op == 16) /* br conditional register */ { dest = regcache_raw_get_unsigned (regcache, tdep->ppc_lr_regnum) & ~3; /* If we are about to return from a signal handler, dest is something like 0x3c90. The current frame is a signal handler caller frame, upon completion of the sigreturn system call execution will return to the saved PC in the frame. */ if (dest < AIX_TEXT_SEGMENT_BASE) { struct frame_info *frame = get_current_frame (); dest = read_memory_unsigned_integer (get_frame_base (frame) + SIG_FRAME_PC_OFFSET, tdep->wordsize, byte_order); } } else if (ext_op == 528) /* br cond to count reg */ { dest = regcache_raw_get_unsigned (regcache, tdep->ppc_ctr_regnum) & ~3; /* If we are about to execute a system call, dest is something like 0x22fc or 0x3b00. Upon completion the system call will return to the address in the link register. */ if (dest < AIX_TEXT_SEGMENT_BASE) dest = regcache_raw_get_unsigned (regcache, tdep->ppc_lr_regnum) & ~3; } else return -1; break; default: return -1; } return (dest < AIX_TEXT_SEGMENT_BASE) ? safety : dest; } /* AIX does not support PT_STEP. Simulate it. */ static std::vector rs6000_software_single_step (struct regcache *regcache) { struct gdbarch *gdbarch = regcache->arch (); enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); int ii, insn; CORE_ADDR loc; CORE_ADDR breaks[2]; int opcode; loc = regcache_read_pc (regcache); insn = read_memory_integer (loc, 4, byte_order); std::vector next_pcs = ppc_deal_with_atomic_sequence (regcache); if (!next_pcs.empty ()) return next_pcs; breaks[0] = loc + PPC_INSN_SIZE; opcode = insn >> 26; breaks[1] = branch_dest (regcache, opcode, insn, loc, breaks[0]); /* Don't put two breakpoints on the same address. */ if (breaks[1] == breaks[0]) breaks[1] = -1; for (ii = 0; ii < 2; ++ii) { /* ignore invalid breakpoint. */ if (breaks[ii] == -1) continue; next_pcs.push_back (breaks[ii]); } errno = 0; /* FIXME, don't ignore errors! */ /* What errors? {read,write}_memory call error(). */ return next_pcs; } /* Implement the "auto_wide_charset" gdbarch method for this platform. */ static const char * rs6000_aix_auto_wide_charset (void) { return "UTF-16"; } /* Implement an osabi sniffer for RS6000/AIX. This function assumes that ABFD's flavour is XCOFF. In other words, it should be registered as a sniffer for bfd_target_xcoff_flavour objfiles only. A failed assertion will be raised if this condition is not met. */ static enum gdb_osabi rs6000_aix_osabi_sniffer (bfd *abfd) { gdb_assert (bfd_get_flavour (abfd) == bfd_target_xcoff_flavour); /* The only noticeable difference between Lynx178 XCOFF files and AIX XCOFF files comes from the fact that there are no shared libraries on Lynx178. On AIX, we are betting that an executable linked with no shared library will never exist. */ if (xcoff_get_n_import_files (abfd) <= 0) return GDB_OSABI_UNKNOWN; return GDB_OSABI_AIX; } /* A structure encoding the offset and size of a field within a struct. */ struct field_info { int offset; int size; }; /* A structure describing the layout of all the fields of interest in AIX's struct ld_info. Each field in this struct corresponds to the field of the same name in struct ld_info. */ struct ld_info_desc { struct field_info ldinfo_next; struct field_info ldinfo_fd; struct field_info ldinfo_textorg; struct field_info ldinfo_textsize; struct field_info ldinfo_dataorg; struct field_info ldinfo_datasize; struct field_info ldinfo_filename; }; /* The following data has been generated by compiling and running the following program on AIX 5.3. */ #if 0 #include #include #define __LDINFO_PTRACE32__ #define __LDINFO_PTRACE64__ #include #define pinfo(type,member) \ { \ struct type ldi = {0}; \ \ printf (" {%d, %d},\t/* %s */\n", \ offsetof (struct type, member), \ sizeof (ldi.member), \ #member); \ } \ while (0) int main (void) { printf ("static const struct ld_info_desc ld_info32_desc =\n{\n"); pinfo (__ld_info32, ldinfo_next); pinfo (__ld_info32, ldinfo_fd); pinfo (__ld_info32, ldinfo_textorg); pinfo (__ld_info32, ldinfo_textsize); pinfo (__ld_info32, ldinfo_dataorg); pinfo (__ld_info32, ldinfo_datasize); pinfo (__ld_info32, ldinfo_filename); printf ("};\n"); printf ("\n"); printf ("static const struct ld_info_desc ld_info64_desc =\n{\n"); pinfo (__ld_info64, ldinfo_next); pinfo (__ld_info64, ldinfo_fd); pinfo (__ld_info64, ldinfo_textorg); pinfo (__ld_info64, ldinfo_textsize); pinfo (__ld_info64, ldinfo_dataorg); pinfo (__ld_info64, ldinfo_datasize); pinfo (__ld_info64, ldinfo_filename); printf ("};\n"); return 0; } #endif /* 0 */ /* Layout of the 32bit version of struct ld_info. */ static const struct ld_info_desc ld_info32_desc = { {0, 4}, /* ldinfo_next */ {4, 4}, /* ldinfo_fd */ {8, 4}, /* ldinfo_textorg */ {12, 4}, /* ldinfo_textsize */ {16, 4}, /* ldinfo_dataorg */ {20, 4}, /* ldinfo_datasize */ {24, 2}, /* ldinfo_filename */ }; /* Layout of the 64bit version of struct ld_info. */ static const struct ld_info_desc ld_info64_desc = { {0, 4}, /* ldinfo_next */ {8, 4}, /* ldinfo_fd */ {16, 8}, /* ldinfo_textorg */ {24, 8}, /* ldinfo_textsize */ {32, 8}, /* ldinfo_dataorg */ {40, 8}, /* ldinfo_datasize */ {48, 2}, /* ldinfo_filename */ }; /* A structured representation of one entry read from the ld_info binary data provided by the AIX loader. */ struct ld_info { ULONGEST next; int fd; CORE_ADDR textorg; ULONGEST textsize; CORE_ADDR dataorg; ULONGEST datasize; char *filename; char *member_name; }; /* Return a struct ld_info object corresponding to the entry at LDI_BUF. Note that the filename and member_name strings still point to the data in LDI_BUF. So LDI_BUF must not be deallocated while the struct ld_info object returned is in use. */ static struct ld_info rs6000_aix_extract_ld_info (struct gdbarch *gdbarch, const gdb_byte *ldi_buf) { struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); struct type *ptr_type = builtin_type (gdbarch)->builtin_data_ptr; const struct ld_info_desc desc = tdep->wordsize == 8 ? ld_info64_desc : ld_info32_desc; struct ld_info info; info.next = extract_unsigned_integer (ldi_buf + desc.ldinfo_next.offset, desc.ldinfo_next.size, byte_order); info.fd = extract_signed_integer (ldi_buf + desc.ldinfo_fd.offset, desc.ldinfo_fd.size, byte_order); info.textorg = extract_typed_address (ldi_buf + desc.ldinfo_textorg.offset, ptr_type); info.textsize = extract_unsigned_integer (ldi_buf + desc.ldinfo_textsize.offset, desc.ldinfo_textsize.size, byte_order); info.dataorg = extract_typed_address (ldi_buf + desc.ldinfo_dataorg.offset, ptr_type); info.datasize = extract_unsigned_integer (ldi_buf + desc.ldinfo_datasize.offset, desc.ldinfo_datasize.size, byte_order); info.filename = (char *) ldi_buf + desc.ldinfo_filename.offset; info.member_name = info.filename + strlen (info.filename) + 1; return info; } /* Append to OBJSTACK an XML string description of the shared library corresponding to LDI, following the TARGET_OBJECT_LIBRARIES_AIX format. */ static void rs6000_aix_shared_library_to_xml (struct ld_info *ldi, struct obstack *obstack) { obstack_grow_str (obstack, "filename); obstack_grow_str (obstack, p.c_str ()); obstack_grow_str (obstack, "\""); if (ldi->member_name[0] != '\0') { obstack_grow_str (obstack, " member=\""); p = xml_escape_text (ldi->member_name); obstack_grow_str (obstack, p.c_str ()); obstack_grow_str (obstack, "\""); } obstack_grow_str (obstack, " text_addr=\""); obstack_grow_str (obstack, core_addr_to_string (ldi->textorg)); obstack_grow_str (obstack, "\""); obstack_grow_str (obstack, " text_size=\""); obstack_grow_str (obstack, pulongest (ldi->textsize)); obstack_grow_str (obstack, "\""); obstack_grow_str (obstack, " data_addr=\""); obstack_grow_str (obstack, core_addr_to_string (ldi->dataorg)); obstack_grow_str (obstack, "\""); obstack_grow_str (obstack, " data_size=\""); obstack_grow_str (obstack, pulongest (ldi->datasize)); obstack_grow_str (obstack, "\""); obstack_grow_str (obstack, ">"); } /* Convert the ld_info binary data provided by the AIX loader into an XML representation following the TARGET_OBJECT_LIBRARIES_AIX format. LDI_BUF is a buffer containing the ld_info data. READBUF, OFFSET and LEN follow the same semantics as target_ops' to_xfer_partial target_ops method. If CLOSE_LDINFO_FD is nonzero, then this routine also closes the ldinfo_fd file descriptor. This is useful when the ldinfo data is obtained via ptrace, as ptrace opens a file descriptor for each and every entry; but we cannot use this descriptor as the consumer of the XML library list might live in a different process. */ ULONGEST rs6000_aix_ld_info_to_xml (struct gdbarch *gdbarch, const gdb_byte *ldi_buf, gdb_byte *readbuf, ULONGEST offset, ULONGEST len, int close_ldinfo_fd) { struct obstack obstack; const char *buf; ULONGEST len_avail; obstack_init (&obstack); obstack_grow_str (&obstack, "\n"); while (1) { struct ld_info ldi = rs6000_aix_extract_ld_info (gdbarch, ldi_buf); rs6000_aix_shared_library_to_xml (&ldi, &obstack); if (close_ldinfo_fd) close (ldi.fd); if (!ldi.next) break; ldi_buf = ldi_buf + ldi.next; } obstack_grow_str0 (&obstack, "\n"); buf = (const char *) obstack_finish (&obstack); len_avail = strlen (buf); if (offset >= len_avail) len= 0; else { if (len > len_avail - offset) len = len_avail - offset; memcpy (readbuf, buf + offset, len); } obstack_free (&obstack, NULL); return len; } /* Implement the core_xfer_shared_libraries_aix gdbarch method. */ static ULONGEST rs6000_aix_core_xfer_shared_libraries_aix (struct gdbarch *gdbarch, gdb_byte *readbuf, ULONGEST offset, ULONGEST len) { struct bfd_section *ldinfo_sec; int ldinfo_size; ldinfo_sec = bfd_get_section_by_name (core_bfd, ".ldinfo"); if (ldinfo_sec == NULL) error (_("cannot find .ldinfo section from core file: %s"), bfd_errmsg (bfd_get_error ())); ldinfo_size = bfd_get_section_size (ldinfo_sec); gdb::byte_vector ldinfo_buf (ldinfo_size); if (! bfd_get_section_contents (core_bfd, ldinfo_sec, ldinfo_buf.data (), 0, ldinfo_size)) error (_("unable to read .ldinfo section from core file: %s"), bfd_errmsg (bfd_get_error ())); return rs6000_aix_ld_info_to_xml (gdbarch, ldinfo_buf.data (), readbuf, offset, len, 0); } static void rs6000_aix_init_osabi (struct gdbarch_info info, struct gdbarch *gdbarch) { struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); /* RS6000/AIX does not support PT_STEP. Has to be simulated. */ set_gdbarch_software_single_step (gdbarch, rs6000_software_single_step); /* Displaced stepping is currently not supported in combination with software single-stepping. */ set_gdbarch_displaced_step_copy_insn (gdbarch, NULL); set_gdbarch_displaced_step_fixup (gdbarch, NULL); set_gdbarch_displaced_step_location (gdbarch, NULL); set_gdbarch_push_dummy_call (gdbarch, rs6000_push_dummy_call); set_gdbarch_return_value (gdbarch, rs6000_return_value); set_gdbarch_long_double_bit (gdbarch, 8 * TARGET_CHAR_BIT); /* Handle RS/6000 function pointers (which are really function descriptors). */ set_gdbarch_convert_from_func_ptr_addr (gdbarch, rs6000_convert_from_func_ptr_addr); /* Core file support. */ set_gdbarch_iterate_over_regset_sections (gdbarch, rs6000_aix_iterate_over_regset_sections); set_gdbarch_core_xfer_shared_libraries_aix (gdbarch, rs6000_aix_core_xfer_shared_libraries_aix); if (tdep->wordsize == 8) tdep->lr_frame_offset = 16; else tdep->lr_frame_offset = 8; if (tdep->wordsize == 4) /* PowerOpen / AIX 32 bit. The saved area or red zone consists of 19 4 byte GPRS + 18 8 byte FPRs giving a total of 220 bytes. Problem is, 220 isn't frame (16 byte) aligned. Round it up to 224. */ set_gdbarch_frame_red_zone_size (gdbarch, 224); else set_gdbarch_frame_red_zone_size (gdbarch, 0); if (tdep->wordsize == 8) set_gdbarch_wchar_bit (gdbarch, 32); else set_gdbarch_wchar_bit (gdbarch, 16); set_gdbarch_wchar_signed (gdbarch, 0); set_gdbarch_auto_wide_charset (gdbarch, rs6000_aix_auto_wide_charset); set_solib_ops (gdbarch, &solib_aix_so_ops); frame_unwind_append_unwinder (gdbarch, &aix_sighandle_frame_unwind); } void _initialize_rs6000_aix_tdep (void) { gdbarch_register_osabi_sniffer (bfd_arch_rs6000, bfd_target_xcoff_flavour, rs6000_aix_osabi_sniffer); gdbarch_register_osabi_sniffer (bfd_arch_powerpc, bfd_target_xcoff_flavour, rs6000_aix_osabi_sniffer); gdbarch_register_osabi (bfd_arch_rs6000, 0, GDB_OSABI_AIX, rs6000_aix_init_osabi); gdbarch_register_osabi (bfd_arch_powerpc, 0, GDB_OSABI_AIX, rs6000_aix_init_osabi); }