1# Copyright 1992-2013 Free Software Foundation, Inc. 2 3# This program is free software; you can redistribute it and/or modify 4# it under the terms of the GNU General Public License as published by 5# the Free Software Foundation; either version 3 of the License, or 6# (at your option) any later version. 7# 8# This program is distributed in the hope that it will be useful, 9# but WITHOUT ANY WARRANTY; without even the implied warranty of 10# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11# GNU General Public License for more details. 12# 13# You should have received a copy of the GNU General Public License 14# along with this program. If not, see <http://www.gnu.org/licenses/>. 15 16# This file was written by Jeff Law. (law@cs.utah.edu) 17 18 19set testfile "recurse" 20set srcfile ${testfile}.c 21set binfile ${objdir}/${subdir}/${testfile} 22if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } { 23 untested recurse.exp 24 return -1 25} 26 27# Start with a fresh gdb. 28 29gdb_exit 30gdb_start 31gdb_reinitialize_dir $srcdir/$subdir 32gdb_load ${binfile} 33 34proc recurse_tests {} { 35 36 # Disable hardware watchpoints if necessary. 37 if [target_info exists gdb,no_hardware_watchpoints] { 38 gdb_test_no_output "set can-use-hw-watchpoints 0" "" 39 } 40 41 if [runto recurse] then { 42 # First we need to step over the assignment of b, so it has a known 43 # value. 44 gdb_test "next" "if \\(a == 1\\)" "next over b = 0 in first instance" 45 gdb_test "watch b" ".*\[Ww\]atchpoint \[0-9]*: b" \ 46 "set first instance watchpoint" 47 48 # Continue until initial set of b. 49 if [gdb_test "continue" \ 50 "Continuing.*\[Ww\]atchpoint.*: b.*Old value = 0.*New value = 10.*" \ 51 "continue to first instance watchpoint, first time"] then { 52 gdb_suppress_tests; 53 } 54 55 # Continue inward for a few iterations 56 gdb_test "continue" "Breakpoint.* recurse \\(a=9\\).*" \ 57 "continue to recurse (a = 9)" 58 gdb_test "continue" "Breakpoint.* recurse \\(a=8\\).*" \ 59 "continue to recurse (a = 8)" 60 gdb_test "continue" "Breakpoint.* recurse \\(a=7\\).*" \ 61 "continue to recurse (a = 7)" 62 gdb_test "continue" "Breakpoint.* recurse \\(a=6\\).*" \ 63 "continue to recurse (a = 6)" 64 gdb_test "continue" "Breakpoint.* recurse \\(a=5\\).*" \ 65 "continue to recurse (a = 5)" 66 67 # Put a watchpoint on another instance of b 68 # First we need to step over the assignment of b, so it has a known 69 # value. 70 gdb_test "next" "if \\(a == 1\\)" "next over b = 0 in second instance" 71 gdb_test "watch b" ".*\[Ww\]atchpoint \[0-9]*: b" \ 72 "set second instance watchpoint" 73 74 # Continue until initial set of b (second instance). 75 if [gdb_test "continue" \ 76 "Continuing.*\[Ww\]atchpoint.*: b.*Old value = 0.*New value = 5.*"\ 77 "continue to second instance watchpoint, first time"] then { 78 gdb_suppress_tests; 79 } 80 81 # Continue inward for a few iterations 82 gdb_test "continue" "Breakpoint.* recurse \\(a=4\\).*" \ 83 "continue to recurse (a = 4)" 84 gdb_test "continue" "Breakpoint.* recurse \\(a=3\\).*" \ 85 "continue to recurse (a = 3)" 86 gdb_test "continue" "Breakpoint.* recurse \\(a=2\\).*" \ 87 "continue to recurse (a = 2)" 88 gdb_test "continue" "Breakpoint.* recurse \\(a=1\\).*" \ 89 "continue to recurse (a = 1)" 90 91 # Continue until second set of b (second instance). 92 if [gdb_test "continue" \ 93 "Continuing.*\[Ww\]atchpoint.*: b.*Old value = 5.*New value = 120.*return.*" \ 94 "continue to second instance watchpoint, second time"] then { 95 gdb_suppress_tests; 96 } 97 98 # Continue again. We should have a watchpoint go out of scope now 99 if [gdb_test "continue" \ 100 "Continuing.*\[Ww\]atchpoint.*deleted.*recurse \\(a=6\\) .*" \ 101 "second instance watchpoint deleted when leaving scope"] then { 102 gdb_suppress_tests; 103 } 104 105 # Continue until second set of b (first instance). 106 # 24320 is allowed as the final value for b as that's the value 107 # b would have on systems with 16bit integers. 108 # 109 # We could fix the test program to deal with this too. 110 if [gdb_test "continue" \ 111 "Continuing.*\[Ww\]atchpoint.*b.*Old value = 10.*New value = \(3628800|24320\).*return.*" \ 112 "continue to first instance watchpoint, second time"] then { 113 gdb_suppress_tests 114 } 115 116 # Continue again. We should have a watchpoint go out of scope now. 117 # 118 # The former version expected the test to return to main(). 119 # Now it expects the test to return to main or to stop in the 120 # function's epilogue. 121 # 122 # The problem is that gdb needs to (but doesn't) understand 123 # function epilogues in the same way as for prologues. 124 # 125 # If there is no hardware watchpoint (such as a x86 debug register), 126 # then watchpoints are done "the hard way" by single-stepping the 127 # target until the value of the watched variable changes. If you 128 # are single-stepping, you will eventually step into an epilogue. 129 # When you do that, the "top" stack frame may become partially 130 # deconstructed (as when you pop the frame pointer, for instance), 131 # and from that point on, GDB can no longer make sense of the stack. 132 # 133 # A test which stops in the epilogue is trying to determine when GDB 134 # leaves the stack frame in which the watchpoint was created. It does 135 # this basically by watching for the frame pointer to change. When 136 # the frame pointer changes, the test expects to be back in main, but 137 # instead it is still in the epilogue of the callee. 138 if [gdb_test "continue" \ 139 "Continuing.*\[Ww\]atchpoint.*deleted.*\(main \\(\\) \|21.*\}\).*" \ 140 "first instance watchpoint deleted when leaving scope"] then { 141 gdb_suppress_tests; 142 } 143 } 144 gdb_stop_suppressing_tests; 145} 146 147# Preserve the old timeout, and set a new one that should be 148# sufficient to avoid timing out during this test. 149set oldtimeout $timeout 150set timeout [expr "$timeout + 60"] 151verbose "Timeout is now $timeout seconds" 2 152 153recurse_tests 154 155# Restore the preserved old timeout value. 156set timeout $oldtimeout 157verbose "Timeout is now $timeout seconds" 2 158 159