gdb/arch/ppc-linux-common.c

   1 /* Common target dependent code for GNU/Linux on PPC systems.
   2
   3    Copyright (C) 2018-2022 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "gdbsupport/common-defs.h"
  21 #include "arch/ppc-linux-common.h"
  22 #include "arch/ppc-linux-tdesc.h"
  23
  24 /* Decimal Floating Point bit in AT_HWCAP.
  25
  26    This file can be used by a host with another architecture, e.g.
  27    when debugging core files, which might not provide this constant.  */
  28
  29 #ifndef PPC_FEATURE_HAS_DFP
  30 #define PPC_FEATURE_HAS_DFP     0x00000400
  31 #endif
  32
  33 bool
  34 ppc_linux_has_isa205 (CORE_ADDR hwcap)
  35 {
  36   /* Power ISA 2.05 (implemented by Power 6 and newer processors)
  37      increases the FPSCR from 32 bits to 64 bits.  Even though Power 7
  38      supports this ISA version, it doesn't have PPC_FEATURE_ARCH_2_05
  39      set, only PPC_FEATURE_ARCH_2_06.  Since for now the only bits
  40      used in the higher half of the register are for Decimal Floating
  41      Point, we check if that feature is available to decide the size
  42      of the FPSCR.  */
  43   return ((hwcap & PPC_FEATURE_HAS_DFP) != 0);
  44 }
  45
  46 const struct target_desc *
  47 ppc_linux_match_description (struct ppc_linux_features features)
  48 {
  49   struct target_desc *tdesc = NULL;
  50
  51   if (features.wordsize == 8)
  52     {
  53       if (features.vsx)
  54         tdesc = (features.htm? tdesc_powerpc_isa207_htm_vsx64l
  55                  : features.isa207? tdesc_powerpc_isa207_vsx64l
  56                  : features.ppr_dscr? tdesc_powerpc_isa205_ppr_dscr_vsx64l
  57                  : features.isa205? tdesc_powerpc_isa205_vsx64l
  58                  : tdesc_powerpc_vsx64l);
  59       else if (features.altivec)
  60         tdesc = (features.isa205? tdesc_powerpc_isa205_altivec64l
  61                  : tdesc_powerpc_altivec64l);
  62       else
  63         tdesc = (features.isa205? tdesc_powerpc_isa205_64l
  64                  : tdesc_powerpc_64l);
  65     }
  66   else
  67     {
  68       gdb_assert (features.wordsize == 4);
  69
  70       if (features.vsx)
  71         tdesc = (features.htm? tdesc_powerpc_isa207_htm_vsx32l
  72                  : features.isa207? tdesc_powerpc_isa207_vsx32l
  73                  : features.ppr_dscr? tdesc_powerpc_isa205_ppr_dscr_vsx32l
  74                  : features.isa205? tdesc_powerpc_isa205_vsx32l
  75                  : tdesc_powerpc_vsx32l);
  76       else if (features.altivec)
  77         tdesc = (features.isa205? tdesc_powerpc_isa205_altivec32l
  78                  : tdesc_powerpc_altivec32l);
  79       else
  80         tdesc = (features.isa205? tdesc_powerpc_isa205_32l
  81                  : tdesc_powerpc_32l);
  82     }
  83
  84   gdb_assert (tdesc != NULL);
  85
  86   return tdesc;
  87 }