gdb/testsuite/lib/cache.exp

   1 # Copyright 2012-2022 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
  17 # The in-memory cache.
  18 array set gdb_data_cache {}
  19
  20 # Print pass message msg into gdb.log
  21 proc ignore_pass { msg } {
  22     verbose -log "gdb_do_cache_wrap ignoring pass: $msg"
  23 }
  24
  25 # Call proc real_name and return the result, while ignoring calls to pass.
  26 proc gdb_do_cache_wrap {real_name} {
  27     if { [info procs save_pass] != "" } {
  28         return [uplevel 2 $real_name]
  29     }
  30
  31     rename pass save_pass
  32     rename ignore_pass pass
  33
  34     set code [catch {uplevel 2 $real_name} result]
  35
  36     rename pass ignore_pass
  37     rename save_pass pass
  38
  39     if {$code == 1} {
  40         global errorInfo errorCode
  41         return -code error -errorinfo $errorInfo -errorcode $errorCode $result
  42     } elseif {$code > 1} {
  43         return -code $code $result
  44     }
  45
  46     return $result
  47 }
  48
  49 # A helper for gdb_caching_proc that handles the caching.
  50
  51 proc gdb_do_cache {name} {
  52     global gdb_data_cache objdir
  53     global GDB_PARALLEL
  54
  55     # Normally, if we have a cached value, we skip computation and return
  56     # the cached value.  If set to 1, instead don't skip computation and
  57     # verify against the cached value.
  58     set cache_verify 0
  59
  60     # Alternatively, set this to do cache_verify only for one proc.
  61     set cache_verify_proc ""
  62     if { $name == $cache_verify_proc } {
  63         set cache_verify 1
  64     }
  65
  66     # See if some other process wrote the cache file.  Cache value per
  67     # "board" to handle runs with multiple options
  68     # (e.g. unix/{-m32,-64}) correctly.  We use "file join" here
  69     # because we later use this in a real filename.
  70     set cache_name [file join [target_info name] $name]
  71
  72     set is_cached 0
  73     if {[info exists gdb_data_cache($cache_name)]} {
  74         set cached $gdb_data_cache($cache_name)
  75         verbose "$name: returning '$cached' from cache" 2
  76         if { $cache_verify == 0 } {
  77             return $cached
  78         }
  79         set is_cached 1
  80     }
  81
  82     if { $is_cached == 0 && [info exists GDB_PARALLEL] } {
  83         set cache_filename [make_gdb_parallel_path cache $cache_name]
  84         if {[file exists $cache_filename]} {
  85             set fd [open $cache_filename]
  86             set gdb_data_cache($cache_name) [read -nonewline $fd]
  87             close $fd
  88             set cached $gdb_data_cache($cache_name)
  89             verbose "$name: returning '$cached' from file cache" 2
  90             if { $cache_verify == 0 } {
  91                 return $cached
  92             }
  93             set is_cached 1
  94         }
  95     }
  96
  97     set real_name gdb_real__$name
  98     set gdb_data_cache($cache_name) [gdb_do_cache_wrap $real_name]
  99     if { $cache_verify == 1 && $is_cached == 1 } {
 100         set computed $gdb_data_cache($cache_name)
 101         if { $cached != $computed } {
 102             error [join [list "Inconsistent results for $cache_name:"
 103                          "cached: $cached vs. computed: $computed"]]
 104         }
 105     }
 106
 107     if {[info exists GDB_PARALLEL]} {
 108         verbose "$name: returning '$gdb_data_cache($cache_name)' and writing file" 2
 109         file mkdir [file dirname $cache_filename]
 110         # Make sure to write the results file atomically.
 111         set fd [open $cache_filename.[pid] w]
 112         puts $fd $gdb_data_cache($cache_name)
 113         close $fd
 114         file rename -force -- $cache_filename.[pid] $cache_filename
 115     }
 116     return $gdb_data_cache($cache_name)
 117 }
 118
 119 # Define a new proc named NAME that takes no arguments.  BODY is the
 120 # body of the proc.  The proc will evaluate BODY and cache the
 121 # results, both in memory and, if GDB_PARALLEL is defined, in the
 122 # filesystem for use across invocations of dejagnu.
 123
 124 proc gdb_caching_proc {name body} {
 125     # Define the underlying proc that we'll call.
 126     set real_name gdb_real__$name
 127     proc $real_name {} $body
 128
 129     # Define the advertised proc.
 130     proc $name {} [list gdb_do_cache $name]
 131 }