796 lines
24 KiB
C
796 lines
24 KiB
C
/* Native support code for PPC AIX, for GDB the GNU debugger.
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Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011
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Free Software Foundation, Inc.
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Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "defs.h"
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#include "gdb_string.h"
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#include "gdb_assert.h"
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#include "osabi.h"
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#include "regcache.h"
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#include "regset.h"
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#include "gdbtypes.h"
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#include "gdbcore.h"
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#include "target.h"
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#include "value.h"
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#include "infcall.h"
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#include "objfiles.h"
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#include "breakpoint.h"
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#include "rs6000-tdep.h"
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#include "ppc-tdep.h"
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#include "exceptions.h"
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/* Hook for determining the TOC address when calling functions in the
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inferior under AIX. The initialization code in rs6000-nat.c sets
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this hook to point to find_toc_address. */
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CORE_ADDR (*rs6000_find_toc_address_hook) (CORE_ADDR) = NULL;
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/* If the kernel has to deliver a signal, it pushes a sigcontext
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structure on the stack and then calls the signal handler, passing
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the address of the sigcontext in an argument register. Usually
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the signal handler doesn't save this register, so we have to
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access the sigcontext structure via an offset from the signal handler
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frame.
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The following constants were determined by experimentation on AIX 3.2. */
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#define SIG_FRAME_PC_OFFSET 96
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#define SIG_FRAME_LR_OFFSET 108
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#define SIG_FRAME_FP_OFFSET 284
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/* Core file support. */
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static struct ppc_reg_offsets rs6000_aix32_reg_offsets =
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{
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/* General-purpose registers. */
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208, /* r0_offset */
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4, /* gpr_size */
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4, /* xr_size */
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24, /* pc_offset */
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28, /* ps_offset */
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32, /* cr_offset */
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36, /* lr_offset */
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40, /* ctr_offset */
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44, /* xer_offset */
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48, /* mq_offset */
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/* Floating-point registers. */
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336, /* f0_offset */
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56, /* fpscr_offset */
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4, /* fpscr_size */
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/* AltiVec registers. */
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-1, /* vr0_offset */
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-1, /* vscr_offset */
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-1 /* vrsave_offset */
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};
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static struct ppc_reg_offsets rs6000_aix64_reg_offsets =
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{
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/* General-purpose registers. */
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0, /* r0_offset */
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8, /* gpr_size */
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4, /* xr_size */
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264, /* pc_offset */
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256, /* ps_offset */
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288, /* cr_offset */
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272, /* lr_offset */
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280, /* ctr_offset */
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292, /* xer_offset */
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-1, /* mq_offset */
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/* Floating-point registers. */
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312, /* f0_offset */
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296, /* fpscr_offset */
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4, /* fpscr_size */
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/* AltiVec registers. */
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-1, /* vr0_offset */
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-1, /* vscr_offset */
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-1 /* vrsave_offset */
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};
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/* Supply register REGNUM in the general-purpose register set REGSET
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from the buffer specified by GREGS and LEN to register cache
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REGCACHE. If REGNUM is -1, do this for all registers in REGSET. */
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static void
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rs6000_aix_supply_regset (const struct regset *regset,
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struct regcache *regcache, int regnum,
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const void *gregs, size_t len)
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{
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ppc_supply_gregset (regset, regcache, regnum, gregs, len);
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ppc_supply_fpregset (regset, regcache, regnum, gregs, len);
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}
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/* Collect register REGNUM in the general-purpose register set
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REGSET, from register cache REGCACHE into the buffer specified by
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GREGS and LEN. If REGNUM is -1, do this for all registers in
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REGSET. */
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static void
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rs6000_aix_collect_regset (const struct regset *regset,
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const struct regcache *regcache, int regnum,
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void *gregs, size_t len)
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{
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ppc_collect_gregset (regset, regcache, regnum, gregs, len);
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ppc_collect_fpregset (regset, regcache, regnum, gregs, len);
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}
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/* AIX register set. */
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static struct regset rs6000_aix32_regset =
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{
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&rs6000_aix32_reg_offsets,
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rs6000_aix_supply_regset,
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rs6000_aix_collect_regset,
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};
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static struct regset rs6000_aix64_regset =
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{
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&rs6000_aix64_reg_offsets,
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rs6000_aix_supply_regset,
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rs6000_aix_collect_regset,
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};
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/* Return the appropriate register set for the core section identified
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by SECT_NAME and SECT_SIZE. */
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static const struct regset *
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rs6000_aix_regset_from_core_section (struct gdbarch *gdbarch,
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const char *sect_name, size_t sect_size)
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{
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if (gdbarch_tdep (gdbarch)->wordsize == 4)
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{
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if (strcmp (sect_name, ".reg") == 0 && sect_size >= 592)
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return &rs6000_aix32_regset;
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}
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else
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{
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if (strcmp (sect_name, ".reg") == 0 && sect_size >= 576)
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return &rs6000_aix64_regset;
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}
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return NULL;
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}
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/* Pass the arguments in either registers, or in the stack. In RS/6000,
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the first eight words of the argument list (that might be less than
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eight parameters if some parameters occupy more than one word) are
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passed in r3..r10 registers. Float and double parameters are
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passed in fpr's, in addition to that. Rest of the parameters if any
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are passed in user stack. There might be cases in which half of the
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parameter is copied into registers, the other half is pushed into
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stack.
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Stack must be aligned on 64-bit boundaries when synthesizing
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function calls.
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If the function is returning a structure, then the return address is passed
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in r3, then the first 7 words of the parameters can be passed in registers,
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starting from r4. */
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static CORE_ADDR
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rs6000_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
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struct regcache *regcache, CORE_ADDR bp_addr,
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int nargs, struct value **args, CORE_ADDR sp,
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int struct_return, CORE_ADDR struct_addr)
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{
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struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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int ii;
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int len = 0;
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int argno; /* current argument number */
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int argbytes; /* current argument byte */
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gdb_byte tmp_buffer[50];
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int f_argno = 0; /* current floating point argno */
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int wordsize = gdbarch_tdep (gdbarch)->wordsize;
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CORE_ADDR func_addr = find_function_addr (function, NULL);
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struct value *arg = 0;
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struct type *type;
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ULONGEST saved_sp;
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/* The calling convention this function implements assumes the
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processor has floating-point registers. We shouldn't be using it
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on PPC variants that lack them. */
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gdb_assert (ppc_floating_point_unit_p (gdbarch));
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/* The first eight words of ther arguments are passed in registers.
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Copy them appropriately. */
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ii = 0;
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/* If the function is returning a `struct', then the first word
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(which will be passed in r3) is used for struct return address.
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In that case we should advance one word and start from r4
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register to copy parameters. */
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if (struct_return)
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{
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regcache_raw_write_unsigned (regcache, tdep->ppc_gp0_regnum + 3,
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struct_addr);
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ii++;
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}
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/* effectively indirect call... gcc does...
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return_val example( float, int);
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eabi:
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float in fp0, int in r3
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offset of stack on overflow 8/16
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for varargs, must go by type.
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power open:
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float in r3&r4, int in r5
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offset of stack on overflow different
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both:
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return in r3 or f0. If no float, must study how gcc emulates floats;
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pay attention to arg promotion.
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User may have to cast\args to handle promotion correctly
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since gdb won't know if prototype supplied or not. */
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for (argno = 0, argbytes = 0; argno < nargs && ii < 8; ++ii)
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{
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int reg_size = register_size (gdbarch, ii + 3);
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arg = args[argno];
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type = check_typedef (value_type (arg));
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len = TYPE_LENGTH (type);
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if (TYPE_CODE (type) == TYPE_CODE_FLT)
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{
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/* Floating point arguments are passed in fpr's, as well as gpr's.
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There are 13 fpr's reserved for passing parameters. At this point
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there is no way we would run out of them. */
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gdb_assert (len <= 8);
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regcache_cooked_write (regcache,
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tdep->ppc_fp0_regnum + 1 + f_argno,
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value_contents (arg));
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++f_argno;
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}
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if (len > reg_size)
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{
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/* Argument takes more than one register. */
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while (argbytes < len)
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{
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gdb_byte word[MAX_REGISTER_SIZE];
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memset (word, 0, reg_size);
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memcpy (word,
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((char *) value_contents (arg)) + argbytes,
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(len - argbytes) > reg_size
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? reg_size : len - argbytes);
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regcache_cooked_write (regcache,
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tdep->ppc_gp0_regnum + 3 + ii,
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word);
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++ii, argbytes += reg_size;
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if (ii >= 8)
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goto ran_out_of_registers_for_arguments;
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}
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argbytes = 0;
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--ii;
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}
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else
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{
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/* Argument can fit in one register. No problem. */
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int adj = gdbarch_byte_order (gdbarch)
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== BFD_ENDIAN_BIG ? reg_size - len : 0;
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gdb_byte word[MAX_REGISTER_SIZE];
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memset (word, 0, reg_size);
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memcpy (word, value_contents (arg), len);
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regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 3 +ii, word);
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}
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++argno;
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}
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ran_out_of_registers_for_arguments:
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regcache_cooked_read_unsigned (regcache,
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gdbarch_sp_regnum (gdbarch),
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&saved_sp);
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/* Location for 8 parameters are always reserved. */
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sp -= wordsize * 8;
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/* Another six words for back chain, TOC register, link register, etc. */
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sp -= wordsize * 6;
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/* Stack pointer must be quadword aligned. */
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sp &= -16;
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/* If there are more arguments, allocate space for them in
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the stack, then push them starting from the ninth one. */
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if ((argno < nargs) || argbytes)
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{
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int space = 0, jj;
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if (argbytes)
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{
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space += ((len - argbytes + 3) & -4);
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jj = argno + 1;
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}
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else
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jj = argno;
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for (; jj < nargs; ++jj)
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{
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struct value *val = args[jj];
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space += ((TYPE_LENGTH (value_type (val))) + 3) & -4;
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}
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/* Add location required for the rest of the parameters. */
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space = (space + 15) & -16;
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sp -= space;
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/* This is another instance we need to be concerned about
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securing our stack space. If we write anything underneath %sp
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(r1), we might conflict with the kernel who thinks he is free
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to use this area. So, update %sp first before doing anything
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else. */
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regcache_raw_write_signed (regcache,
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gdbarch_sp_regnum (gdbarch), sp);
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/* If the last argument copied into the registers didn't fit there
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completely, push the rest of it into stack. */
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if (argbytes)
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{
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write_memory (sp + 24 + (ii * 4),
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value_contents (arg) + argbytes,
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len - argbytes);
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++argno;
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ii += ((len - argbytes + 3) & -4) / 4;
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}
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/* Push the rest of the arguments into stack. */
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for (; argno < nargs; ++argno)
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{
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arg = args[argno];
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type = check_typedef (value_type (arg));
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len = TYPE_LENGTH (type);
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/* Float types should be passed in fpr's, as well as in the
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stack. */
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if (TYPE_CODE (type) == TYPE_CODE_FLT && f_argno < 13)
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{
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gdb_assert (len <= 8);
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regcache_cooked_write (regcache,
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tdep->ppc_fp0_regnum + 1 + f_argno,
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value_contents (arg));
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++f_argno;
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}
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write_memory (sp + 24 + (ii * 4), value_contents (arg), len);
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ii += ((len + 3) & -4) / 4;
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}
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}
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/* Set the stack pointer. According to the ABI, the SP is meant to
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be set _before_ the corresponding stack space is used. On AIX,
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this even applies when the target has been completely stopped!
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Not doing this can lead to conflicts with the kernel which thinks
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that it still has control over this not-yet-allocated stack
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region. */
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regcache_raw_write_signed (regcache, gdbarch_sp_regnum (gdbarch), sp);
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/* Set back chain properly. */
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store_unsigned_integer (tmp_buffer, wordsize, byte_order, saved_sp);
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write_memory (sp, tmp_buffer, wordsize);
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/* Point the inferior function call's return address at the dummy's
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breakpoint. */
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regcache_raw_write_signed (regcache, tdep->ppc_lr_regnum, bp_addr);
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/* Set the TOC register, get the value from the objfile reader
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which, in turn, gets it from the VMAP table. */
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if (rs6000_find_toc_address_hook != NULL)
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{
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CORE_ADDR tocvalue = (*rs6000_find_toc_address_hook) (func_addr);
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regcache_raw_write_signed (regcache, tdep->ppc_toc_regnum, tocvalue);
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}
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target_store_registers (regcache, -1);
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return sp;
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}
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static enum return_value_convention
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rs6000_return_value (struct gdbarch *gdbarch, struct type *func_type,
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struct type *valtype, struct regcache *regcache,
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gdb_byte *readbuf, const gdb_byte *writebuf)
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{
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struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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gdb_byte buf[8];
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/* The calling convention this function implements assumes the
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processor has floating-point registers. We shouldn't be using it
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on PowerPC variants that lack them. */
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gdb_assert (ppc_floating_point_unit_p (gdbarch));
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/* AltiVec extension: Functions that declare a vector data type as a
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return value place that return value in VR2. */
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if (TYPE_CODE (valtype) == TYPE_CODE_ARRAY && TYPE_VECTOR (valtype)
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&& TYPE_LENGTH (valtype) == 16)
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{
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if (readbuf)
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regcache_cooked_read (regcache, tdep->ppc_vr0_regnum + 2, readbuf);
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if (writebuf)
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regcache_cooked_write (regcache, tdep->ppc_vr0_regnum + 2, writebuf);
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return RETURN_VALUE_REGISTER_CONVENTION;
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}
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/* If the called subprogram returns an aggregate, there exists an
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implicit first argument, whose value is the address of a caller-
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allocated buffer into which the callee is assumed to store its
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return value. All explicit parameters are appropriately
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relabeled. */
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if (TYPE_CODE (valtype) == TYPE_CODE_STRUCT
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|| TYPE_CODE (valtype) == TYPE_CODE_UNION
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|| TYPE_CODE (valtype) == TYPE_CODE_ARRAY)
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return RETURN_VALUE_STRUCT_CONVENTION;
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/* Scalar floating-point values are returned in FPR1 for float or
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double, and in FPR1:FPR2 for quadword precision. Fortran
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complex*8 and complex*16 are returned in FPR1:FPR2, and
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complex*32 is returned in FPR1:FPR4. */
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if (TYPE_CODE (valtype) == TYPE_CODE_FLT
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&& (TYPE_LENGTH (valtype) == 4 || TYPE_LENGTH (valtype) == 8))
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{
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struct type *regtype = register_type (gdbarch, tdep->ppc_fp0_regnum);
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gdb_byte regval[8];
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/* FIXME: kettenis/2007-01-01: Add support for quadword
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precision and complex. */
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if (readbuf)
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{
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regcache_cooked_read (regcache, tdep->ppc_fp0_regnum + 1, regval);
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convert_typed_floating (regval, regtype, readbuf, valtype);
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}
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if (writebuf)
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{
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convert_typed_floating (writebuf, valtype, regval, regtype);
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regcache_cooked_write (regcache, tdep->ppc_fp0_regnum + 1, regval);
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}
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return RETURN_VALUE_REGISTER_CONVENTION;
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}
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/* Values of the types int, long, short, pointer, and char (length
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is less than or equal to four bytes), as well as bit values of
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lengths less than or equal to 32 bits, must be returned right
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justified in GPR3 with signed values sign extended and unsigned
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values zero extended, as necessary. */
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if (TYPE_LENGTH (valtype) <= tdep->wordsize)
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{
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if (readbuf)
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{
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ULONGEST regval;
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/* For reading we don't have to worry about sign extension. */
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regcache_cooked_read_unsigned (regcache, tdep->ppc_gp0_regnum + 3,
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®val);
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store_unsigned_integer (readbuf, TYPE_LENGTH (valtype), byte_order,
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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 (regcache, tdep->ppc_gp0_regnum + 3, regval);
|
|
regcache_cooked_read (regcache, tdep->ppc_gp0_regnum + 4,
|
|
regval + 4);
|
|
memcpy (readbuf, regval, 8);
|
|
}
|
|
if (writebuf)
|
|
{
|
|
regcache_cooked_write (regcache, tdep->ppc_gp0_regnum + 3, writebuf);
|
|
regcache_cooked_write (regcache, 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;
|
|
struct gdb_exception e;
|
|
|
|
TRY_CATCH (e, RETURN_MASK_ERROR)
|
|
{
|
|
pc = read_memory_unsigned_integer (addr, tdep->wordsize, byte_order);
|
|
}
|
|
if (e.reason < 0)
|
|
{
|
|
/* 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 frame_info *frame, int opcode, int instr,
|
|
CORE_ADDR pc, CORE_ADDR safety)
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (frame);
|
|
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 = get_frame_register_unsigned (frame, 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)
|
|
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 = get_frame_register_unsigned (frame,
|
|
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 = get_frame_register_unsigned (frame,
|
|
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 int
|
|
rs6000_software_single_step (struct frame_info *frame)
|
|
{
|
|
struct gdbarch *gdbarch = get_frame_arch (frame);
|
|
struct address_space *aspace = get_frame_address_space (frame);
|
|
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
|
|
int ii, insn;
|
|
CORE_ADDR loc;
|
|
CORE_ADDR breaks[2];
|
|
int opcode;
|
|
|
|
loc = get_frame_pc (frame);
|
|
|
|
insn = read_memory_integer (loc, 4, byte_order);
|
|
|
|
if (ppc_deal_with_atomic_sequence (frame))
|
|
return 1;
|
|
|
|
breaks[0] = loc + PPC_INSN_SIZE;
|
|
opcode = insn >> 26;
|
|
breaks[1] = branch_dest (frame, 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;
|
|
insert_single_step_breakpoint (gdbarch, aspace, breaks[ii]);
|
|
}
|
|
|
|
errno = 0; /* FIXME, don't ignore errors! */
|
|
/* What errors? {read,write}_memory call error(). */
|
|
return 1;
|
|
}
|
|
|
|
static enum gdb_osabi
|
|
rs6000_aix_osabi_sniffer (bfd *abfd)
|
|
{
|
|
|
|
if (bfd_get_flavour (abfd) == bfd_target_xcoff_flavour);
|
|
return GDB_OSABI_AIX;
|
|
|
|
return GDB_OSABI_UNKNOWN;
|
|
}
|
|
|
|
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_free_closure (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_regset_from_core_section
|
|
(gdbarch, rs6000_aix_regset_from_core_section);
|
|
|
|
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);
|
|
}
|
|
|
|
/* Provide a prototype to silence -Wmissing-prototypes. */
|
|
extern initialize_file_ftype _initialize_rs6000_aix_tdep;
|
|
|
|
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);
|
|
}
|
|
|