fromdigits should allow unstringified bigints

danaj · Aug 15, 2016 · eea9ff9 · eea9ff9
1 parent 5e56bd5
commit eea9ff9
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Showing 3 changed files with 65 additions and 14 deletions.
diff --git a/Changes b/Changes
@@ -1,5 +1,12 @@
 Revision history for Perl module Math::Prime::Util
 
+0.60 2016-?
+
+    [FUNCTIONALITY AND PERFORMANCE]
+
+    - fromdigits works with bigint first arg, no need to stringify.
+      Slightly faster for bigints, but slower than desired.
+
 0.59 2016-08-03
 
     [ADDED]

diff --git a/XS.xs b/XS.xs
@@ -116,6 +116,20 @@ typedef struct {
 
 START_MY_CXT
 
+static int _is_sv_bigint(pTHX_ SV* n)
+{
+  if (sv_isobject(n)) {
+    const char *hvname = HvNAME_get(SvSTASH(SvRV(n)));
+    if (hvname != 0) {
+      if (strEQ(hvname, "Math::BigInt") || strEQ(hvname, "Math::BigFloat") ||
+          strEQ(hvname, "Math::GMPz")   || strEQ(hvname, "Math::GMP") ||
+          strEQ(hvname, "Math::Pari") )
+        return 1;
+    }
+  }
+  return 0;
+}
+
 /* Is this a pedantically valid integer?
  * Croaks if undefined or invalid.
  * Returns 0 if it is an object or a string too large for a UV.
@@ -135,15 +149,8 @@ static int _validate_int(pTHX_ SV* n, int negok)
     else croak("Parameter '%" SVf "' must be a positive integer", n);
   }
   if (sv_isobject(n)) {
-    const char *hvname = HvNAME_get(SvSTASH(SvRV(n)));
-    if (hvname == 0)
-      return 0;
-    if (strEQ(hvname, "Math::BigInt") || strEQ(hvname, "Math::BigFloat") ||
-        strEQ(hvname, "Math::GMPz")   || strEQ(hvname, "Math::GMP") ||
-        strEQ(hvname, "Math::Pari") )
-      isbignum = 1;
-    else
-      return 0;
+    isbignum = _is_sv_bigint(aTHX_ n);
+    if (!isbignum) return 0;
   }
   /* Without being very careful, don't process magic variables here */
   if (SvGAMAGIC(n) && !isbignum) return 0;
@@ -466,6 +473,7 @@ sieve_primes(IN UV low, IN UV high)
     segment_primes = 3
     segment_twin_primes = 4
     _ramanujan_primes = 5
+    n_ramanujan_primes = 6
   PREINIT:
     AV* av;
   PPCODE:
@@ -517,6 +525,13 @@ sieve_primes(IN UV low, IN UV high)
           for (i = beg; i <= end; i++)
             av_push(av,newSVuv(L[i]));
         Safefree(L);
+      } else if (ix == 6) {                   /* Ramanujan primes */
+        UV i, *L;
+        L = n_range_ramanujan_primes(low, high);
+        if (L && high >= low)
+          for (i = low; i <= high; i++)
+            av_push(av,newSVuv(L[i-low]));
+        Safefree(L);
       }
     }
     return; /* skip implicit PUTBACK */
@@ -1794,7 +1809,7 @@ void todigits(SV* svn, int base=10, int length=-1)
         if (from_digit_string(&n, SvPV_nolen(svn), base)) {
           XSRETURN_UV(n);
         }
-      } else {            /* array ref of digits */
+      } else if (!_is_sv_bigint(aTHX_ svn)) {     /* array ref of digits */
         UV* r = 0;
         int len = arrayref_to_int_array(aTHX_ &r, (AV*) SvRV(svn), base);
         if (from_digit_to_UV(&n, r, len, base)) {

diff --git a/lib/Math/Prime/Util/PP.pm b/lib/Math/Prime/Util/PP.pm
@@ -1977,6 +1977,26 @@ sub sum_primes {
   $sum = BZERO->copy if ( (MPU_32BIT && $high >        323_380) ||
                           (MPU_64BIT && $high > 29_505_444_490) );
 
+  if (0 && $low <= 2) {
+    my $n = $high;
+    my $r = sqrtint($n);
+    my @V = map { int($n/$_) } 1 .. $r+1;
+    my $l = $V[-1];
+    push @V, map{ $l-$_ } 1 .. $l;
+    my %S = map { $_ => ($_*($_+1)>>1) - 1 } @V;
+    for my $p (2 .. $r) {
+      if ($S{$p} > $S{$p-1}) {
+        my $sp = $S{$p-1};
+        my $p2 = $p*$p;
+        for my $v (@V) {
+          last if $v < $p2;
+          $S{$v} -= $p * ($S{int($v/$p)} - $sp);
+        }
+      }
+    }
+    return $S{$n};
+  }
+
   # It's very possible we're here because they've counted too high.  Skip fwd.
   if ($low <= 2 && $high >= 29505444491) {
     $low = 29505444503;
@@ -2601,19 +2621,28 @@ sub todigitstring {
 sub fromdigits {
   my($r, $base) = @_;
   $base = 10 unless defined $base;
+  return $r if $base == 10 && ref($r) =~ /^Math::/;
   my $n = BZERO->copy;
   $base = BZERO + $base;
-  if (ref($r)) {
+  if (ref($r) && ref($r) !~ /^Math::/) {
     croak "fromdigits first argument must be a string or array reference"
       unless ref($r) eq 'ARRAY';
     for my $d (@$r) {
       $n = $n * $base + $d;
     }
   } else {
     $r =~ s/^0*//;
-    for my $d (map { $_mapdigit{$_} } split(//,$r)) {
-      croak "Invalid digit for base $base" unless defined $d && $d < $base;
-      $n = $n * $base + $d;
+    #for my $d (map { $_mapdigit{$_} } split(//,$r)) {
+    #  croak "Invalid digit for base $base" unless defined $d && $d < $base;
+    #  $n = $n * $base + $d;
+    #}
+    for my $c (split(//, lc($r))) {
+      $n->bmul($base);
+      if ($c ne '0') {
+        my $d = index("0123456789abcdefghijklmnopqrstuvwxyz", $c);
+        croak "Invalid digit for base $base" unless $d >= 0;
+        $n->badd($d);
+      }
     }
   }
   $n = _bigint_to_int($n) if $n->bacmp(BMAX) <= 0;