Jan Bobek <jan.bo...@gmail.com> writes:
> insnv allows emitting variable-length instructions in little-endian or
> big-endian byte order; it subsumes functionality of former insn16()
> and insn32() functions.
>
> randint can reliably generate signed or unsigned integers of arbitrary
> width.
>
> Signed-off-by: Jan Bobek <jan.bo...@gmail.com>
Reviewed-by: Alex Bennée <alex.ben...@linaro.org>
> ---
> risugen_common.pm | 55 +++++++++++++++++++++++++++++++++++++++++------
> 1 file changed, 48 insertions(+), 7 deletions(-)
>
> diff --git a/risugen_common.pm b/risugen_common.pm
> index 71ee996..d63250a 100644
> --- a/risugen_common.pm
> +++ b/risugen_common.pm
> @@ -23,8 +23,9 @@ BEGIN {
> require Exporter;
>
> our @ISA = qw(Exporter);
> - our @EXPORT = qw(open_bin close_bin set_endian insn32 insn16 $bytecount
> - progress_start progress_update progress_end
> + our @EXPORT = qw(open_bin close_bin set_endian insn32 insn16
> + $bytecount insnv randint progress_start
> + progress_update progress_end
> eval_with_fields is_pow_of_2 sextract ctz
> dump_insn_details);
> }
> @@ -37,7 +38,7 @@ my $bigendian = 0;
> # (default is little endian, 0).
> sub set_endian
> {
> - $bigendian = @_;
> + ($bigendian) = @_;
> }
>
> sub open_bin
> @@ -52,18 +53,58 @@ sub close_bin
> close(BIN) or die "can't close output file: $!";
> }
>
> +sub insnv(%)
> +{
> + my (%args) = @_;
> +
> + # Default to big-endian order, so that the instruction bytes are
> + # emitted in the same order as they are written in the
> + # configuration file.
> + $args{bigendian} = 1 unless defined $args{bigendian};
> +
> + for (my $bitcur = 0; $bitcur < $args{width}; $bitcur += 8) {
> + my $value = $args{value} >> ($args{bigendian}
> + ? $args{width} - $bitcur - 8
> + : $bitcur);
> +
> + print BIN pack("C", $value & 0xff);
> + $bytecount += 1;
> + }
> +}
> +
> sub insn32($)
> {
> my ($insn) = @_;
> - print BIN pack($bigendian ? "N" : "V", $insn);
> - $bytecount += 4;
> + insnv(value => $insn, width => 32, bigendian => $bigendian);
> }
>
> sub insn16($)
> {
> my ($insn) = @_;
> - print BIN pack($bigendian ? "n" : "v", $insn);
> - $bytecount += 2;
> + insnv(value => $insn, width => 16, bigendian => $bigendian);
> +}
> +
> +sub randint
> +{
> + my (%args) = @_;
> + my $width = $args{width};
> +
> + if ($width > 32) {
> + # Generate at most 32 bits at once; Perl's rand() does not
> + # behave well with ranges that are too large.
> + my $lower = randint(%args, width => 32);
> + my $upper = randint(%args, width => $args{width} - 32);
> + # Use arithmetic rather than bitwise operators, since bitwise
> + # ops turn signed integers into unsigned.
> + return $upper * (1 << 32) + $lower;
> + } elsif ($width > 0) {
> + my $halfrange = 1 << ($width - 1);
> + my $value = int(rand(2 * $halfrange));
> + $value -= $halfrange if defined $args{signed} && $args{signed};
> + return $value;
> + } else {
> + return 0;
> + }
> }
>
> # Progress bar implementation
--
Alex Bennée
