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Profiling in Perl


Example 1

Example 1: Profile output for Memoize.pm and fibonacci.pl.

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	<font color="red"><i>output omitted</i></font>
            ================ SmallProf version 0.9 ================
             Profile of /usr/lib/perl5/site_perl/5.005/Memoize.pm      Page 10
       =================================================================
    count wall tm  cpu time line
        0 0.000000 0.000000     1:# -*- mode: perl; perl-indent-level: 2; -*-
        0 0.000000 0.000000     2:# Memoize.pm
        0 0.000000 0.000000     3:#
        0 0.000000 0.000000     4:# Transparent memoization of idempotent
        0 0.000000 0.000000     5:#
        0 0.000000 0.000000     6:# Copyright 1998, 1999 M-J. Dominus.
        0 0.000000 0.000000     7:# You may copy and distribute this program
        0 0.000000 0.000000     8:# same terms as Perl itself.  If in doubt,
        0 0.000000 0.000000     9:# write to mjd-perl-memoize+@plover.com for a
        0 0.000000 0.000000    10:#
        0 0.000000 0.000000    11:# Version 0.62 beta $Revision: 1.17 $ $Date:
        0 0.000000 0.000000    12:
        0 0.000000 0.000000    13:package Memoize;
        0 0.000000 0.000000    14:$VERSION = '0.62';
        0 0.000000 0.000000    15:
        0 0.000000 0.000000    16:# Compile-time constants
      314 0.003152 0.030000    17:sub SCALAR () { 0 }
        4 0.000039 0.000000    18:sub LIST () { 1 }
        0 0.000000 0.000000    19:
        0 0.000000 0.000000    20:
        0 0.000000 0.000000    21:#
        0 0.000000 0.000000    22:# Usage memoize(functionname/ref,
        0 0.000000 0.000000    23:#               { NORMALIZER => coderef,
        0 0.000000 0.000000    24:#                 LIST_CACHE => descriptor,
        0 0.000000 0.000000    25:#
        0 0.000000 0.000000    26:
        0 0.000000 0.000000    27:use Carp;
        0 0.000000 0.000000    28:use Exporter;
        0 0.000000 0.000000    29:use vars qw($DEBUG);
        0 0.000000 0.000000    30:@ISA = qw(Exporter);
        0 0.000000 0.000000    31:@EXPORT = qw(memoize);
        0 0.000000 0.000000    32:@EXPORT_OK = qw(unmemoize flush_cache);
        0 0.000000 0.000000    33:use strict;
        0 0.000000 0.000000    34:
        0 0.000000 0.000000    35:my %memotable;
        0 0.000000 0.000000    36:my %revmemotable;
        0 0.000000 0.000000    37:my @CONTEXT_TAGS = qw(MERGE TIE MEMORY FAULT
        0 0.000000 0.000000    38:my %IS_CACHE_TAG = map {($_ => 1)}
        0 0.000000 0.000000    39:
        0 0.000000 0.000000    40:# Raise an error if the user tries to specify
        0 0.000000 0.000000    41:# tie for LIST_CACHE
        0 0.000000 0.000000    42:
        0 0.000000 0.000000    43:my %scalar_only = map {($_ => 1)} qw(DB_File
        0 0.000000 0.000000    44:
        1 0.000000 0.000000    45:sub memoize {
        1 0.000017 0.000000    46:  my $fn = shift;
        1 0.000017 0.000000    47:  my %options = @_;
        1 0.000014 0.000000    48:  my $options = \%options;
        0 0.000000 0.000000    49:
        1 0.000018 0.000000    50:  unless (defined($fn) &&
        0 0.000000 0.000000    51:   (ref $fn eq 'CODE' || ref $fn eq '')) {
        0 0.000000 0.000000    52:    croak "Usage: memoize
        0 0.000000 0.000000    53:  }
        0 0.000000 0.000000    54:
        1 0.000017 0.000000    55:  my $uppack = caller;  # TCL me Elmo!
        1 0.000008 0.000000    56:  my $cref;   # Code reference to original

            ================ SmallProf version 0.9 ================
             Profile of /usr/lib/perl5/site_perl/5.005/Memoize.pm      Page 11
       =================================================================
    count wall tm  cpu time line
        1 0.000012 0.000000    57:  my $name = (ref $fn ? undef : $fn);
        0 0.000000 0.000000    58:
        0 0.000000 0.000000    59:  # Convert function names to code references
        1 0.000182 0.000000    60:  $cref = &_make_cref($fn, $uppack);
        0 0.000000 0.000000    61:
        0 0.000000 0.000000    62:  # Locate function prototype, if any
        1 0.000014 0.000000    63:  my $proto = prototype $cref;
        1 0.000012 0.000000    64:  if (defined $proto) { $proto = "($proto)" }
        1 0.000015 0.000000    65:  else { $proto = "" }
        0 0.000000 0.000000    66:
        0 0.000000 0.000000    67:  # Goto considered harmful!  Hee hee hee.
        1 0.000541 0.000000    68:  my $wrapper = eval "sub $proto { unshift
        0 0.000000 0.000000    69:  # Actually I would like to get rid of the
        0 0.000000 0.000000    70:  # to be any other way to set the prototype
        0 0.000000 0.000000    71:
        0 0.000000 0.000000    72:# --- THREADED PERL COMMENT ---
        0 0.000000 0.000000    73:# The above line might not work under
        0 0.000000 0.000000    74:# semantics are broken.  If that's the case,
        0 0.000000 0.000000    75:#  my $wrapper = eval "sub {
        0 0.000000 0.000000    76:# Confirmed 1998-12-27 this does work.
        0 0.000000 0.000000    77:# 1998-12-29: Sarathy says this bug is fixed
        0 0.000000 0.000000    78:# However, the module still fails, although
        0 0.000000 0.000000    79:
        1 0.000017 0.000000    80:  my $normalizer = $options{NORMALIZER};
        1 0.000012 0.000000    81:  if (defined $normalizer  && ! ref
        0 0.000000 0.000000    82:    $normalizer = _make_cref($normalizer,
        0 0.000000 0.000000    83:  }
        0 0.000000 0.000000    84:
        1 0.000010 0.000000    85:  my $install_name;
        1 0.000014 0.000000    86:  if (defined $options->{INSTALL}) {
        0 0.000000 0.000000    87:    # INSTALL => name
        0 0.000000 0.000000    88:    $install_name = $options->{INSTALL};
        1 0.000018 0.000000    89:  } elsif (! exists $options->{INSTALL}) {
        0 0.000000 0.000000    90:    # No INSTALL option provided; use
        1 0.000014 0.000000    91:    $install_name = $name;
        0 0.000000 0.000000    92:  } else {
        0 0.000000 0.000000    93:    # INSTALL => undef  means don't install
        0 0.000000 0.000000    94:  }
        0 0.000000 0.000000    95:
        1 0.000010 0.000000    96:  if (defined $install_name) {
        1 0.000030 0.000000    97:    $install_name = $uppack . '::' .
        0 0.000000 0.000000    98: unless $install_name =~ /::/;
        0 0.000000 0.000000    99:    no strict;
        1 0.000026 0.000000   100:    local($^W) = 0;        # ``Subroutine
        2 0.000048 0.000000   101:    *{$install_name} = $wrapper; # Install
        0 0.000000 0.000000   102:  }
        0 0.000000 0.000000   103:
        1 0.000067 0.000000   104:  $revmemotable{$wrapper} = "" . $cref; #
        0 0.000000 0.000000   105:
        0 0.000000 0.000000   106:  # These will be the caches
        1 0.000013 0.000000   107:  my %caches;
        3 0.000059 0.000000   108:  for my $context (qw(SCALAR LIST)) {
        0 0.000000 0.000000   109:    # suppress subsequent 'uninitialized
        2 0.000059 0.000000   110:    $options{"${context}_CACHE"} ||= '';
        0 0.000000 0.000000   111:
        2 0.000041 0.000000   112:    my $cache_opt =

            ================ SmallProf version 0.9 ================
             Profile of /usr/lib/perl5/site_perl/5.005/Memoize.pm      Page 12
       =================================================================
    count wall tm  cpu time line
        2 0.000021 0.000000   113:    my @cache_opt_args;
        2 0.000018 0.000000   114:    if (ref $cache_opt) {
        0 0.000000 0.000000   115:      @cache_opt_args = @$cache_opt;
        0 0.000000 0.000000   116:      $cache_opt = shift @cache_opt_args;
        0 0.000000 0.000000   117:    }
        2 0.000022 0.000000   118:    if ($cache_opt eq 'FAULT') { # no cache
        0 0.000000 0.000000   119:      $caches{$context} = undef;
        2 0.000021 0.000000   120:    } elsif ($cache_opt eq 'HASH') { # user-
        0 0.000000 0.000000   121:      $caches{$context} = $cache_opt_args[0];
        2 0.000023 0.000000   122:    } elsif ($cache_opt eq '' ||
        0 0.000000 0.000000   123:      # default is that we make up an in-
        2 0.000063 0.000000   124:      $caches{$context} = {};
        0 0.000000 0.000000   125:      # (this might get tied later, or MERGEd
        0 0.000000 0.000000   126:    } else {
        0 0.000000 0.000000   127:      croak "Unrecognized option to
        0 0.000000 0.000000   128:    }
        0 0.000000 0.000000   129:  }
        0 0.000000 0.000000   130:
        0 0.000000 0.000000   131:  # Perhaps I should check here that you
        0 0.000000 0.000000   132:  # options.  But if you did, it does do
        0 0.000000 0.000000   133:  # both get merged to the same in-memory
        1 0.000016 0.000000   134:  if ($options{SCALAR_CACHE} eq 'MERGE') {
        0 0.000000 0.000000   135:    $caches{SCALAR} = $caches{LIST};
        1 0.000017 0.000000   136:  } elsif ($options{LIST_CACHE} eq 'MERGE') {
        0 0.000000 0.000000   137:    $caches{LIST} = $caches{SCALAR};
        0 0.000000 0.000000   138:  }
        0 0.000000 0.000000   139:
        0 0.000000 0.000000   140:  # Now deal with the TIE options
        0 0.000000 0.000000   141:  {
        2 0.000023 0.000000   142:    my $context;
        3 0.000060 0.000000   143:    foreach $context (qw(SCALAR LIST)) {
        0 0.000000 0.000000   144:      # If the relevant option wasn't `TIE',
        2 0.000337 0.000000   145:      _my_tie($context, $caches{$context},
        0 0.000000 0.000000   146:    }
        0 0.000000 0.000000   147:  }
        0 0.000000 0.000000   148:
        0 0.000000 0.000000   149:  # We should put some more stuff in here
        0 0.000000 0.000000   150:  # We've been saying that for serveral
        0 0.000000 0.000000   151:  # And you know what?  More stuff keeps
        1 0.000092 0.000000   152:  $memotable{$cref} =
        0 0.000000 0.000000   153:  {
        0 0.000000 0.000000   154:    O => $options,  # Short keys here for
        0 0.000000 0.000000   155:    N => $normalizer,
        0 0.000000 0.000000   156:    U => $cref,
        0 0.000000 0.000000   157:    MEMOIZED => $wrapper,
        0 0.000000 0.000000   158:    PACKAGE => $uppack,
        0 0.000000 0.000000   159:    NAME => $install_name,
        0 0.000000 0.000000   160:    S => $caches{SCALAR},
        0 0.000000 0.000000   161:    L => $caches{LIST},
        0 0.000000 0.000000   162:  };
        0 0.000000 0.000000   163:
        1 0.000031 0.000000   164:  $wrapper   # Return just memoized version
        0 0.000000 0.000000   165:}
        0 0.000000 0.000000   166:
        0 0.000000 0.000000   167:# This function tries to load a tied hash
        2 0.000000 0.000000   168:sub _my_tie {

            ================ SmallProf version 0.9 ================
             Profile of /usr/lib/perl5/site_perl/5.005/Memoize.pm      Page 13
       =================================================================
    count wall tm  cpu time line
        2 0.000036 0.000000   169:  my ($context, $hash, $options) = @_;
        2 0.000039 0.000000   170:  my $fullopt = $options-
        0 0.000000 0.000000   171:
        0 0.000000 0.000000   172:  # We already checked to make sure that this
        2 0.000023 0.000000   173:  my $shortopt = (ref $fullopt) ? $fullopt-
        0 0.000000 0.000000   174:
        2 0.000050 0.000000   175:  return unless defined $shortopt &&
        0 0.000000 0.000000   176:
        0 0.000000 0.000000   177:  my @args = ref $fullopt ? @$fullopt : ();
        0 0.000000 0.000000   178:  shift @args;
        0 0.000000 0.000000   179:  my $module = shift @args;
        0 0.000000 0.000000   180:  if ($context eq 'LIST' &&
        0 0.000000 0.000000   181:    croak("You can't use $module for
        0 0.000000 0.000000   182:  }
        0 0.000000 0.000000   183:  my $modulefile = $module . '.pm';
        0 0.000000 0.000000   184:  $modulefile =~ s{::}{/}g;
        0 0.000000 0.000000   185:  eval { require $modulefile };
        0 0.000000 0.000000   186:  if ($@) {
        0 0.000000 0.000000   187:    croak "Memoize: Couldn't load hash tie
        0 0.000000 0.000000   188:  }
        0 0.000000 0.000000   189:#  eval  { import $module };
        0 0.000000 0.000000   190:#  if ($@) {
        0 0.000000 0.000000   191:#    croak "Memoize: Couldn't import hash tie
        0 0.000000 0.000000   192:#  }
        0 0.000000 0.000000   193:#  eval "use $module ()";
        0 0.000000 0.000000   194:#  if ($@) {
        0 0.000000 0.000000   195:#    croak "Memoize: Couldn't use hash tie
        0 0.000000 0.000000   196:#  }
        0 0.000000 0.000000   197:  my $rc = (tie %$hash => $module, @args);
        0 0.000000 0.000000   198:  unless ($rc) {
        0 0.000000 0.000000   199:    croak "Memoize: Couldn't tie hash to
        0 0.000000 0.000000   200:  }
        0 0.000000 0.000000   201:  1;
        0 0.000000 0.000000   202:}
        0 0.000000 0.000000   203:
        0 0.000000 0.000000   204:sub flush_cache {
        0 0.000000 0.000000   205:  my $func = _make_cref($_[0], scalar
        0 0.000000 0.000000   206:  my $info =
        0 0.000000 0.000000   207:  die "$func not memoized" unless defined
        0 0.000000 0.000000   208:  for my $context (qw(S L)) {
        0 0.000000 0.000000   209:    my $cache = $info->{$context};
        0 0.000000 0.000000   210:    if (tied %$cache && ! (tied %$cache)-
        0 0.000000 0.000000   211:      my $funcname = defined($info->{NAME}) ?
        0 0.000000 0.000000   212:          "function $info->{NAME}" :
        0 0.000000 0.000000   213:      my $context = {S => 'scalar', L =>
        0 0.000000 0.000000   214:      croak "Tied cache hash for $context-
        0 0.000000 0.000000   215:    } else {
        0 0.000000 0.000000   216:      %$cache = ();
        0 0.000000 0.000000   217:    }
        0 0.000000 0.000000   218:  }
        0 0.000000 0.000000   219:}
        0 0.000000 0.000000   220:
        0 0.000000 0.000000   221:# This is the function that manages the memo
        0 0.000000 0.000000   222:sub _memoizer {
       79 0.001108 0.000000   223:  my $orig = shift;  # stringized version of
       79 0.001127 0.000000   224:  my $info = $memotable{$orig};

            ================ SmallProf version 0.9 ================
             Profile of /usr/lib/perl5/site_perl/5.005/Memoize.pm      Page 14
       =================================================================
    count wall tm  cpu time line
       79 0.000889 0.000000   225:  my $normalizer = $info->{N};
        0 0.000000 0.000000   226:
       79 0.000639 0.020000   227:  my $argstr;
       79 0.012471 0.000000   228:  my $context = (wantarray() ? LIST :
        0 0.000000 0.000000   229:
       79 0.000763 0.000000   230:  if (defined $normalizer) {
        0 0.000000 0.000000   231:    no strict;
        0 0.000000 0.000000   232:    if ($context == SCALAR) {
        0 0.000000 0.000000   233:      $argstr = &{$normalizer}(@_);
        0 0.000000 0.000000   234:    } elsif ($context == LIST) {
        0 0.000000 0.000000   235:      ($argstr) = &{$normalizer}(@_);
        0 0.000000 0.000000   236:    } else {
        0 0.000000 0.000000   237:      croak "Internal error \#41; context was
        0 0.000000 0.000000   238:    }
        0 0.000000 0.000000   239:  } else {                      # Default
       79 0.091889 0.010000   240:    $argstr = join $;,@_;       # $;,@_;?
        0 0.000000 0.000000   241:  }
        0 0.000000 0.000000   242:
       79 0.012210 0.020000   243:  if ($context == SCALAR) {
       78 0.001069 0.010000   244:    my $cache = $info->{S};
       78 0.000772 0.000000   245:    _crap_out($info->{NAME}, 'scalar') unless
       78 0.001056 0.010000   246:    if (exists $cache->{$argstr}) {
       38 0.001693 0.010000   247:      return $cache->{$argstr};
        0 0.000000 0.000000   248:    } else {
       80 0.004003 0.010000   249:      my $val = &{$info->{U}}(@_);
        0 0.000000 0.000000   250:      # Scalars are considered to be lists;
       40 0.000709 0.000000   251:      if ($info->{O}{SCALAR_CACHE} eq
        0 0.000000 0.000000   252: $cache->{$argstr} = [$val];
        0 0.000000 0.000000   253:      } else {
       40 0.000859 0.000000   254: $cache->{$argstr} = $val;
        0 0.000000 0.000000   255:      }
       40 0.003255 0.000000   256:      $val;
        0 0.000000 0.000000   257:    }
        1 0.000151 0.000000   258:  } elsif ($context == LIST) {
        1 0.000015 0.000000   259:    my $cache = $info->{L};
        1 0.000011 0.000000   260:    _crap_out($info->{NAME}, 'list') unless
        1 0.000014 0.000000   261:    if (exists $cache->{$argstr}) {
        0 0.000000 0.000000   262:      my $val = $cache->{$argstr};
        0 0.000000 0.000000   263:      return ($val) unless ref $val eq
        0 0.000000 0.000000   264:      # An array ref is ambiguous. Did the
        0 0.000000 0.000000   265:      # an array ref?  Or did we cache a
        0 0.000000 0.000000   266:      # an anonymous array?
        0 0.000000 0.000000   267:      # If LISTCONTEXT=>MERGE, then the
        0 0.000000 0.000000   268:      # so we know for sure:
        0 0.000000 0.000000   269:      return ($val) if $info->{O}{LIST_CACHE}
        0 0.000000 0.000000   270:      # Otherwise, we're doomed.  ###BUG
        0 0.000000 0.000000   271:      return @$val;
        0 0.000000 0.000000   272:    } else {
        2 0.000082 0.000000   273:      my $q = $cache->{$argstr} = [&{$info-
        1 0.000590 0.000000   274:      @$q;
        0 0.000000 0.000000   275:    }
        0 0.000000 0.000000   276:  } else {
        0 0.000000 0.000000   277:    croak "Internal error \#42; context was
        0 0.000000 0.000000   278:  }
        0 0.000000 0.000000   279:}
        0 0.000000 0.000000   280:

            ================ SmallProf version 0.9 ================
             Profile of /usr/lib/perl5/site_perl/5.005/Memoize.pm      Page 15
       =================================================================
    count wall tm  cpu time line
        0 0.000000 0.000000   281:sub unmemoize {
        0 0.000000 0.000000   282:  my $f = shift;
        0 0.000000 0.000000   283:  my $uppack = caller;
        0 0.000000 0.000000   284:  my $cref = _make_cref($f, $uppack);
        0 0.000000 0.000000   285:
        0 0.000000 0.000000   286:  unless (exists $revmemotable{$cref}) {
        0 0.000000 0.000000   287:    croak "Could not unmemoize function `$f',
        0 0.000000 0.000000   288:  }
        0 0.000000 0.000000   289:
        0 0.000000 0.000000   290:  my $tabent =
        0 0.000000 0.000000   291:  unless (defined $tabent) {
        0 0.000000 0.000000   292:    croak "Could not figure out how to
        0 0.000000 0.000000   293:  }
        0 0.000000 0.000000   294:  my $name = $tabent->{NAME};
        0 0.000000 0.000000   295:  if (defined $name) {
        0 0.000000 0.000000   296:    no strict;
        0 0.000000 0.000000   297:    local($^W) = 0;        # ``Subroutine
        0 0.000000 0.000000   298:    *{$name} = $tabent->{U}; # Replace with
        0 0.000000 0.000000   299:  }
        0 0.000000 0.000000   300:  undef $memotable{$revmemotable{$cref}};
        0 0.000000 0.000000   301:  undef $revmemotable{$cref};
        0 0.000000 0.000000   302:
        0 0.000000 0.000000   303:  # This removes the last reference to the
        0 0.000000 0.000000   304:  # my ($old_function, $memotabs) =
        0 0.000000 0.000000   305:  # undef $tabent;
        0 0.000000 0.000000   306:
        0 0.000000 0.000000   307:#  # Untie the memo tables if they were tied.
        0 0.000000 0.000000   308:#  my $i;
        0 0.000000 0.000000   309:#  for $i (0,1) {
        0 0.000000 0.000000   310:#    if (tied %{$memotabs->[$i]}) {
        0 0.000000 0.000000   311:#      warn "Untying hash #$i\n";
        0 0.000000 0.000000   312:#      untie %{$memotabs->[$i]};
        0 0.000000 0.000000   313:#    }
        0 0.000000 0.000000   314:#  }
        0 0.000000 0.000000   315:
        0 0.000000 0.000000   316:  $tabent->{U};
        0 0.000000 0.000000   317:}
        0 0.000000 0.000000   318:
        1 0.000000 0.000000   319:sub _make_cref {
        1 0.000019 0.000000   320:  my $fn = shift;
        1 0.000023 0.000000   321:  my $uppack = shift;
        1 0.000009 0.000000   322:  my $cref;
        1 0.000008 0.000000   323:  my $name;
        0 0.000000 0.000000   324:
        1 0.000012 0.000000   325:  if (ref $fn eq 'CODE') {
        0 0.000000 0.000000   326:    $cref = $fn;
        1 0.000014 0.000000   327:  } elsif (! ref $fn) {
        1 0.000019 0.000000   328:    if ($fn =~ /::/) {
        0 0.000000 0.000000   329:      $name = $fn;
        0 0.000000 0.000000   330:    } else {
        1 0.000025 0.000000   331:      $name = $uppack . '::' . $fn;
        0 0.000000 0.000000   332:    }
        0 0.000000 0.000000   333:    no strict;
        1 0.000021 0.000000   334:    if (defined $name and !defined(&$name)) {
        0 0.000000 0.000000   335:      croak "Cannot operate on nonexistent
        0 0.000000 0.000000   336:    }

            ================ SmallProf version 0.9 ================
             Profile of /usr/lib/perl5/site_perl/5.005/Memoize.pm      Page 16
       =================================================================
    count wall tm  cpu time line
        0 0.000000 0.000000   337:#    $cref = \&$name;
        2 0.000040 0.000000   338:    $cref = *{$name}{CODE};
        0 0.000000 0.000000   339:  } else {
        0 0.000000 0.000000   340:    my $parent = (caller(1))[3]; # Function
        0 0.000000 0.000000   341:    croak "Usage: argument 1 to `$parent'
        0 0.000000 0.000000   342:  }
        1 0.000010 0.000000   343:  $DEBUG and warn "${name}($fn) => $cref in
        1 0.000020 0.000000   344:  $cref;
        0 0.000000 0.000000   345:}
        0 0.000000 0.000000   346:
        0 0.000000 0.000000   347:sub _crap_out {
        0 0.000000 0.000000   348:  my ($funcname, $context) = @_;
        0 0.000000 0.000000   349:  if (defined $funcname) {
        0 0.000000 0.000000   350:    croak "Function `$funcname' called in
        0 0.000000 0.000000   351:  } else {
        0 0.000000 0.000000   352:    croak "Anonymous function called in
        0 0.000000 0.000000   353:  }
        0 0.000000 0.000000   354:}
        0 0.000000 0.000000   355:
        0 0.000000 0.000000   356:1;

	
	<font color="red"><i>output omitted</i></font>

            ================ SmallProf version 0.9 ================
                              Profile of fibonacci.pl                      Page 28
       =================================================================
    count wall tm  cpu time line
        0 0.000000 0.000000     1:#!/usr/bin/perl
        0 0.000000 0.000000     2:
        0 0.000000 0.000000     3:use Memoize;
        0 0.000000 0.000000     4:
        1 0.000204 0.000000     5:memoize('fibonacci');
        0 0.000000 0.000000     6:
        0 0.000000 0.000000     7:sub fibonacci
        0 0.000000 0.000000     8:        {
       41 0.000663 0.000000     9:        my $index = shift;
        0 0.000000 0.000000    10:
       41 0.000446 0.000000    11:        return 0 if $index == 0;
       40 0.000395 0.000000    12:        return 1 if $index == 1;
        0 0.000000 0.000000    13:
       39 0.002819 0.000000    14:        return fibonacci( $index - 1 ) +
        0 0.000000 0.000000    15:        }
        0 0.000000 0.000000    16:
        1 0.000078 0.000000    17:print "F($ARGV[0]) is ", fibonacci($ARGV[0]),
        0 0.000000 0.000000    18:
        0 0.000000 0.000000    19:__END__	
        


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