sim/ppc/idecode_branch.h

   1 /*  This file is part of the program psim.
   2
   3     Copyright (C) 1994-1995, Andrew Cagney <cagney@highland.com.au>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 3 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program; if not, see <http://www.gnu.org/licenses/>.
  17
  18     */
  19
  20
  21 /* branch macro's:
  22
  23    The macro's below implement the semantics of the PowerPC jump
  24    instructions. */
  25
  26
  27 /* If so required, update the Link Register with the next sequential
  28    instruction address */
  29
  30 #define UPDATE_LK \
  31 do { \
  32   if (update_LK) { \
  33     ppc_ia target = cia + 4; \
  34     ppc_spr new_address = (ppc_spr)IEA_MASKED(ppc_is_64bit(processor), \
  35                                               target); \
  36     LR = new_address; \
  37   } \
  38   ITRACE(trace_branch, \
  39          ("UPDATE_LK - update_LK=%d lr=0x%x cia=0x%x\n", \
  40           update_LK, LR, cia); \
  41 } while (0)
  42
  43
  44 /* take the branch - absolute or relative - possibly updating the link
  45    register */
  46
  47 #define BRANCH(ADDRESS) \
  48 do { \
  49   UPDATE_LK; \
  50   if (update_AA) { \
  51     ppc_ia target = (ppc_ia)(ADDRESS); \
  52     nia = (ppc_ia)IEA_MASKED(ppc_is_64bit(processor), target); \
  53   } \
  54   else { \
  55     ppc_ia target = cia + ADDRESS; \
  56     nia = (ppc_ia)IEA_MASKED(ppc_is_64bit(processor), target); \
  57   } \
  58   PTRACE(trace_branch, \
  59          ("BRANCH - update_AA=%d update_LK=%d nia=0x%x cia=0x%x\n", \
  60           update_AA, update_LK, nia, cia); \
  61 } while (0)