gdb/testsuite/gdb.arch/arc-dbnz.exp

   1 # This testcase is part of GDB, the GNU debugger.
   2
   3 # Copyright 2024 Free Software Foundation, Inc.
   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 # Test dbnz instruction. It decrements its source register operand, and if
  19 # the result is non-zero it branches to the location defined by a signed
  20 # half-word displacement operand.
  21 #
  22 # It's necessary to verify these cases:
  23 #
  24 #     1. Check that dbnz does not branch and falls through if its source
  25 #        register is 0 after decrementing. GDB must successfully break
  26 #        on the following instruction after stepping over.
  27 #     2. Check that dbnz branches to the target correctly if its source register
  28 #        is not 0 after decrementing - GDB must successfully break on the target
  29 #        instruction if a forward branch is performed after stepping over.
  30 #     3. The same as point 2 but for a backward branching case.
  31
  32 require {istarget "arc*-*-*"}
  33
  34 standard_testfile .S
  35
  36 if { [prepare_for_testing "failed to prepare" $testfile $srcfile] } {
  37     return -1
  38 }
  39
  40 if ![runto_main] {
  41     return 0
  42 }
  43
  44 gdb_test "break dbnz1" \
  45          "Breakpoint $decimal at .*" \
  46          "set breakpoint on the 1st dbnz"
  47
  48 gdb_test "break dbnz2" \
  49          "Breakpoint $decimal at .*" \
  50          "set breakpoint on the 2nd dbnz"
  51
  52 gdb_test "break dbnz3" \
  53          "Breakpoint $decimal at .*" \
  54          "set breakpoint on the 3rd dbnz"
  55
  56 gdb_test "break dbnz4" \
  57          "Breakpoint $decimal at .*" \
  58          "set breakpoint on the 4th dbnz"
  59
  60 gdb_test "break end" \
  61          "Breakpoint $decimal at .*" \
  62          "set breakpoint at the end"
  63
  64 gdb_test "continue" \
  65          "Breakpoint $decimal, dbnz1.*dbnz r0,@end" \
  66          "continue to the 1st dbnz"
  67
  68 gdb_test "x /i \$pc" \
  69          "$hex <.*>:\[ \t\]+dbnz\[ \t\]+r0,24.*" \
  70          "stayng on the 1st dbnz instruction"
  71
  72 gdb_test "stepi" \
  73          "mov r0,5" \
  74          "step over the 1st dbnz, branch is not taken"
  75
  76 gdb_test "stepi" \
  77          "Breakpoint $decimal, dbnz2.*dbnz\\.d r0,@dbnz3" \
  78          "step over r0 initialization, staying on the 2nd dbnz"
  79
  80 # Linux steps over delay slot after "stepi", but stubs with hardware stepping
  81 # like nSIM's stub may step right on delay slot. Thus use "continue" instead of
  82 # "stepi" to make this test work for all platforms.
  83 gdb_test "continue" \
  84          "Breakpoint $decimal, dbnz3.*dbnz r0,@dbnz4" \
  85          "step over the 2nd dbnz, branch is taken, staying on the 3rd dbnz"
  86
  87 gdb_test "stepi" \
  88          "Breakpoint $decimal, dbnz4.*dbnz r0,@end" \
  89          "step over the 3rd dbnz, branch is taken, staying on the 4th dbnz"
  90
  91 gdb_test "stepi" \
  92          "Breakpoint $decimal, end.*mov r0,0" \
  93          "step over the 4th dbnz, branch is taken, staying on the epilogue"
  94
  95 gdb_test "info register r0" \
  96          "r0\[ \t\]+0x1\[ \t\]+1" \
  97          "r0 contains 1 after all dbnz instructions"