gdb/testsuite/gdb.base/recurse.exp

   1 # Copyright 1992, 1994, 1995, 1996, 1997, 1999, 2000, 2007, 2008, 2009
   2 # Free Software Foundation, Inc.
   3
   4 # This program is free software; you can redistribute it and/or modify
   5 # it under the terms of the GNU General Public License as published by
   6 # the Free Software Foundation; either version 3 of the License, or
   7 # (at your option) any later version.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU General Public License
  15 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 # This file was written by Jeff Law. (law@cs.utah.edu)
  18
  19 if $tracelevel then {
  20     strace $tracelevel
  21 }
  22
  23 set prms_id 0
  24 set bug_id 0
  25
  26 set testfile "recurse"
  27 set srcfile ${testfile}.c
  28 set binfile ${objdir}/${subdir}/${testfile}
  29 if  { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
  30      untested recurse.exp
  31      return -1
  32 }
  33
  34 # Start with a fresh gdb.
  35
  36 gdb_exit
  37 gdb_start
  38 gdb_reinitialize_dir $srcdir/$subdir
  39 gdb_load ${binfile}
  40
  41 proc recurse_tests {} {
  42
  43     # Disable hardware watchpoints if necessary.
  44     if [target_info exists gdb,no_hardware_watchpoints] {
  45         gdb_test "set can-use-hw-watchpoints 0" "" ""
  46     }
  47
  48     if [runto recurse] then {
  49         # First we need to step over the assignment of b, so it has a known
  50         # value.
  51         gdb_test "next" "if \\(a == 1\\)" "next over b = 0 in first instance"
  52         gdb_test "watch b" ".*\[Ww\]atchpoint \[0-9]*: b" \
  53             "set first instance watchpoint"
  54
  55         # Continue until initial set of b.
  56         if [gdb_test "continue" \
  57             "Continuing.*\[Ww\]atchpoint.*: b.*Old value = 0.*New value = 10.*" \
  58             "continue to first instance watchpoint, first time"] then {
  59             gdb_suppress_tests;
  60         }
  61
  62         # Continue inward for a few iterations
  63         gdb_test "continue" "Breakpoint.* recurse \\(a=9\\).*" \
  64             "continue to recurse (a = 9)"
  65         gdb_test "continue" "Breakpoint.* recurse \\(a=8\\).*" \
  66             "continue to recurse (a = 8)"
  67         gdb_test "continue" "Breakpoint.* recurse \\(a=7\\).*" \
  68             "continue to recurse (a = 7)"
  69         gdb_test "continue" "Breakpoint.* recurse \\(a=6\\).*" \
  70             "continue to recurse (a = 6)"
  71         gdb_test "continue" "Breakpoint.* recurse \\(a=5\\).*" \
  72             "continue to recurse (a = 5)"
  73
  74         # Put a watchpoint on another instance of b
  75         # First we need to step over the assignment of b, so it has a known
  76         # value.
  77         gdb_test "next" "if \\(a == 1\\)" "next over b = 0 in second instance"
  78         gdb_test "watch b" ".*\[Ww\]atchpoint \[0-9]*: b" \
  79             "set second instance watchpoint"
  80
  81         # Continue until initial set of b (second instance).
  82         if [gdb_test "continue" \
  83             "Continuing.*\[Ww\]atchpoint.*: b.*Old value = 0.*New value = 5.*"\
  84             "continue to second instance watchpoint, first time"] then {
  85         gdb_suppress_tests;
  86         }
  87
  88         # Continue inward for a few iterations
  89         gdb_test "continue" "Breakpoint.* recurse \\(a=4\\).*" \
  90             "continue to recurse (a = 4)"
  91         gdb_test "continue" "Breakpoint.* recurse \\(a=3\\).*" \
  92             "continue to recurse (a = 3)"
  93         gdb_test "continue" "Breakpoint.* recurse \\(a=2\\).*" \
  94             "continue to recurse (a = 2)"
  95         gdb_test "continue" "Breakpoint.* recurse \\(a=1\\).*" \
  96             "continue to recurse (a = 1)"
  97
  98         # Continue until second set of b (second instance).
  99         if [gdb_test "continue" \
 100             "Continuing.*\[Ww\]atchpoint.*: b.*Old value = 5.*New value = 120.*return.*" \
 101             "continue to second instance watchpoint, second time"] then {
 102             gdb_suppress_tests;
 103         }
 104
 105         # Continue again.  We should have a watchpoint go out of scope now
 106         if [gdb_test "continue" \
 107             "Continuing.*\[Ww\]atchpoint.*deleted.*recurse \\(a=6\\) .*" \
 108             "second instance watchpoint deleted when leaving scope"] then {
 109             gdb_suppress_tests;
 110         }
 111
 112         # Continue until second set of b (first instance).
 113         # 24320 is allowed as the final value for b as that's the value
 114         # b would have on systems with 16bit integers.
 115         #
 116         # We could fix the test program to deal with this too.
 117         if [gdb_test "continue" \
 118             "Continuing.*\[Ww\]atchpoint.*b.*Old value = 10.*New value = \(3628800|24320\).*return.*" \
 119             "continue to first instance watchpoint, second time"] then {
 120             gdb_suppress_tests
 121         }
 122
 123         # Continue again.  We should have a watchpoint go out of scope now.
 124         #
 125         # The former version expected the test to return to main().
 126         # Now it expects the test to return to main or to stop in the
 127         # function's epilogue.
 128         #
 129         # The problem is that gdb needs to (but doesn't) understand
 130         # function epilogues in the same way as for prologues.
 131         #
 132         # If there is no hardware watchpoint (such as a x86 debug register),
 133         # then watchpoints are done "the hard way" by single-stepping the
 134         # target until the value of the watched variable changes.  If you
 135         # are single-stepping, you will eventually step into an epilogue.
 136         # When you do that, the "top" stack frame may become partially
 137         # deconstructed (as when you pop the frame pointer, for instance),
 138         # and from that point on, GDB can no longer make sense of the stack.
 139         #
 140         # A test which stops in the epilogue is trying to determine when GDB
 141         # leaves the stack frame in which the watchpoint was created.  It does
 142         # this basically by watching for the frame pointer to change.  When
 143         # the frame pointer changes, the test expects to be back in main, but
 144         # instead it is still in the epilogue of the callee.
 145         if [gdb_test "continue" \
 146             "Continuing.*\[Ww\]atchpoint.*deleted.*\(main \\(\\) \|21.*\}\).*" \
 147             "first instance watchpoint deleted when leaving scope"] then {
 148             gdb_suppress_tests;
 149         }
 150     }
 151     gdb_stop_suppressing_tests;
 152 }
 153
 154 # Preserve the old timeout, and set a new one that should be
 155 # sufficient to avoid timing out during this test.
 156 set oldtimeout $timeout
 157 set timeout [expr "$timeout + 60"]
 158 verbose "Timeout is now $timeout seconds" 2
 159
 160 recurse_tests
 161
 162 # Restore the preserved old timeout value.
 163 set timeout $oldtimeout
 164 verbose "Timeout is now $timeout seconds" 2
 165