my @F = split /\s*=\s*/;
    
    push @rows, [map {
        my %x = (field => $F[$_ - 1], value => $F[$_]);
        $x{field} =~ s/.*\s+(\S+)$/$1/ unless $_ == 1;
        $x{value} =~ s/\s*\S+$// unless $_ == $#F;
        \%x;
    } 1 .. $#F];
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You could improve that a great deal if you just used one of the splits already given with the slight modification of capturing the field name. There's no need for all the conditionals, substitutions, array indexing, and length checking. It's more readable too. . .

 my ($toss, @list) = split /\s*([A-Za-z]+)\s*\=\s*/;
 my @row;
 while (@list) {
     push @row, { field => shift @list,
                  value => shift @list };

 }
 push @rows, \@row;
[download]