[gnumeric] process-amath: simplify and work around perl bug.

[Morten Welinder <mortenw src gnome org>]

commit 709135245c88dac7b85637297afb24db67920038
Author: Morten Welinder <terra gnome org>
Date:   Thu Oct 31 14:59:25 2013 -0400

    process-amath: simplify and work around perl bug.
    
    Perl mistakes 0.1530e-305 for zero.  Work around that.

 tools/process-amath.pl |   49 ++++++++++++++++++++++++++++++-----------------
 1 files changed, 31 insertions(+), 18 deletions(-)
---
diff --git a/tools/process-amath.pl b/tools/process-amath.pl
old mode 100644
new mode 100755
index 8b07232..6b4cd5c
--- a/tools/process-amath.pl
+++ b/tools/process-amath.pl
@@ -179,6 +179,34 @@ sub reorder_handler {
 
 # -----------------------------------------------------------------------------
 
+sub simplify_val {
+    my ($val,$pvars) = @_;
+
+    $val =~ s/^\s+//;
+    $val =~ s/\s+$//;
+
+    # Avoid a perl bug that underflows 0.153e-305
+    while ($val =~ /^(.*)\b0\.(\d)(\d*)[eE]-(\d+)\b(.*)$/) {
+       $val = "$1$2.$3e-" . ($4 + 1) . $5;
+    }
+
+    $val =~ s/\bldexp\s*\(\s*([-+.eE0-9_]+)\s*[,;]\s*([-+]?\d+)\s*\)/($1*2^$2)/g;
+
+    if ($val =~ m{^[-+*/^() .eE0-9]+$}) {
+       print STDERR "ZZZ:$val\n" if $val =~ /^[-+]?[0-9.]+[eE][-+]?\d+$/ && $val == 0;
+       return 0 if $val =~ /^[-+]?[0-9.]+[eE][-+]?\d+$/ && $val == 0;
+
+       return $val;
+    } elsif (exists $pvars->{$val}) {
+       return $pvars->{$val};
+    } else {
+       print STDERR "XXX:[$val]\n";
+       return undef;
+    }
+}
+
+# -----------------------------------------------------------------------------
+
 foreach my $f (@test_files) {
     my $fn = "$dir/tests/$f";
 
@@ -213,23 +241,8 @@ foreach my $f (@test_files) {
            my $ok = 1;
 
            foreach (@args) {
-               s/^\s+//;
-               s/\s+$//;
-               if (m{^[-+*/() .eE0-9]+$}) {
-                   $_ = 0 if /^[-+]?[0-9.]+[eE][-+]?\d+$/ && $_ == 0;
-                   next;
-               } elsif (exists $vars{$_}) {
-                   $_ = $vars{$_};
-                   next;
-               } elsif (/^ldexp\(([-+.eE0-9_]+);([-+]?\d+)\)$/) {
-                   $_ = "2^$2";
-                   $_ = "$1*$_" unless $1 == 1;
-               } elsif (/^1\s*-\s*ldexp\(([-+.eE0-9_]+);([-+]?\d+)\)$/) {
-                   $_ = "2^$2";
-                   $_ = "$1*$_" unless $1 == 1;
-                   $_ = "1-$_";
-               } else {
-                   print STDERR "XXX:[$_]\n";
+               $_ = &simplify_val ($_, \%vars);
+               if (!defined $_) {
                    $ok = 0;
                    last;
                }
@@ -243,7 +256,7 @@ foreach my $f (@test_files) {
        while (s/^\s*([a-zA-Z0-9]+)\s*:=\s*([-+.eE0-9_]+)\s*;//) {
            my $var = $1;
            my $val = $2;
-           $val = 0 if $val =~ /^[-+]?[0-9.]+[eE][-+]?\d+$/ && $val == 0;
+           $val = &simplify_val ($val, \%vars);
            $vars{$var} = $val;
        }