1# Copyright 1992, 1994, 1995, 1996, 1997, 1999, 2000, 2007, 2008, 2009, 2010, 2# 2011 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 19if $tracelevel then { 20 strace $tracelevel 21} 22 23 24set testfile "recurse" 25set srcfile ${testfile}.c 26set binfile ${objdir}/${subdir}/${testfile} 27if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } { 28 untested recurse.exp 29 return -1 30} 31 32# Start with a fresh gdb. 33 34gdb_exit 35gdb_start 36gdb_reinitialize_dir $srcdir/$subdir 37gdb_load ${binfile} 38 39proc recurse_tests {} { 40 41 # Disable hardware watchpoints if necessary. 42 if [target_info exists gdb,no_hardware_watchpoints] { 43 gdb_test_no_output "set can-use-hw-watchpoints 0" "" 44 } 45 46 if [runto recurse] then { 47 # First we need to step over the assignment of b, so it has a known 48 # value. 49 gdb_test "next" "if \\(a == 1\\)" "next over b = 0 in first instance" 50 gdb_test "watch b" ".*\[Ww\]atchpoint \[0-9]*: b" \ 51 "set first instance watchpoint" 52 53 # Continue until initial set of b. 54 if [gdb_test "continue" \ 55 "Continuing.*\[Ww\]atchpoint.*: b.*Old value = 0.*New value = 10.*" \ 56 "continue to first instance watchpoint, first time"] then { 57 gdb_suppress_tests; 58 } 59 60 # Continue inward for a few iterations 61 gdb_test "continue" "Breakpoint.* recurse \\(a=9\\).*" \ 62 "continue to recurse (a = 9)" 63 gdb_test "continue" "Breakpoint.* recurse \\(a=8\\).*" \ 64 "continue to recurse (a = 8)" 65 gdb_test "continue" "Breakpoint.* recurse \\(a=7\\).*" \ 66 "continue to recurse (a = 7)" 67 gdb_test "continue" "Breakpoint.* recurse \\(a=6\\).*" \ 68 "continue to recurse (a = 6)" 69 gdb_test "continue" "Breakpoint.* recurse \\(a=5\\).*" \ 70 "continue to recurse (a = 5)" 71 72 # Put a watchpoint on another instance of b 73 # First we need to step over the assignment of b, so it has a known 74 # value. 75 gdb_test "next" "if \\(a == 1\\)" "next over b = 0 in second instance" 76 gdb_test "watch b" ".*\[Ww\]atchpoint \[0-9]*: b" \ 77 "set second instance watchpoint" 78 79 # Continue until initial set of b (second instance). 80 if [gdb_test "continue" \ 81 "Continuing.*\[Ww\]atchpoint.*: b.*Old value = 0.*New value = 5.*"\ 82 "continue to second instance watchpoint, first time"] then { 83 gdb_suppress_tests; 84 } 85 86 # Continue inward for a few iterations 87 gdb_test "continue" "Breakpoint.* recurse \\(a=4\\).*" \ 88 "continue to recurse (a = 4)" 89 gdb_test "continue" "Breakpoint.* recurse \\(a=3\\).*" \ 90 "continue to recurse (a = 3)" 91 gdb_test "continue" "Breakpoint.* recurse \\(a=2\\).*" \ 92 "continue to recurse (a = 2)" 93 gdb_test "continue" "Breakpoint.* recurse \\(a=1\\).*" \ 94 "continue to recurse (a = 1)" 95 96 # Continue until second set of b (second instance). 97 if [gdb_test "continue" \ 98 "Continuing.*\[Ww\]atchpoint.*: b.*Old value = 5.*New value = 120.*return.*" \ 99 "continue to second instance watchpoint, second time"] then { 100 gdb_suppress_tests; 101 } 102 103 # Continue again. We should have a watchpoint go out of scope now 104 if [gdb_test "continue" \ 105 "Continuing.*\[Ww\]atchpoint.*deleted.*recurse \\(a=6\\) .*" \ 106 "second instance watchpoint deleted when leaving scope"] then { 107 gdb_suppress_tests; 108 } 109 110 # Continue until second set of b (first instance). 111 # 24320 is allowed as the final value for b as that's the value 112 # b would have on systems with 16bit integers. 113 # 114 # We could fix the test program to deal with this too. 115 if [gdb_test "continue" \ 116 "Continuing.*\[Ww\]atchpoint.*b.*Old value = 10.*New value = \(3628800|24320\).*return.*" \ 117 "continue to first instance watchpoint, second time"] then { 118 gdb_suppress_tests 119 } 120 121 # Continue again. We should have a watchpoint go out of scope now. 122 # 123 # The former version expected the test to return to main(). 124 # Now it expects the test to return to main or to stop in the 125 # function's epilogue. 126 # 127 # The problem is that gdb needs to (but doesn't) understand 128 # function epilogues in the same way as for prologues. 129 # 130 # If there is no hardware watchpoint (such as a x86 debug register), 131 # then watchpoints are done "the hard way" by single-stepping the 132 # target until the value of the watched variable changes. If you 133 # are single-stepping, you will eventually step into an epilogue. 134 # When you do that, the "top" stack frame may become partially 135 # deconstructed (as when you pop the frame pointer, for instance), 136 # and from that point on, GDB can no longer make sense of the stack. 137 # 138 # A test which stops in the epilogue is trying to determine when GDB 139 # leaves the stack frame in which the watchpoint was created. It does 140 # this basically by watching for the frame pointer to change. When 141 # the frame pointer changes, the test expects to be back in main, but 142 # instead it is still in the epilogue of the callee. 143 if [gdb_test "continue" \ 144 "Continuing.*\[Ww\]atchpoint.*deleted.*\(main \\(\\) \|21.*\}\).*" \ 145 "first instance watchpoint deleted when leaving scope"] then { 146 gdb_suppress_tests; 147 } 148 } 149 gdb_stop_suppressing_tests; 150} 151 152# Preserve the old timeout, and set a new one that should be 153# sufficient to avoid timing out during this test. 154set oldtimeout $timeout 155set timeout [expr "$timeout + 60"] 156verbose "Timeout is now $timeout seconds" 2 157 158recurse_tests 159 160# Restore the preserved old timeout value. 161set timeout $oldtimeout 162verbose "Timeout is now $timeout seconds" 2 163 164