Merge pull request #4 from clearmatics/exceptions-fix

Exceptions fix - merge scipr-lab/libfqfft#12 (depends on #6)

Author: AntoineRondelet

libfqfft/evaluation_domain/domains/arithmetic_sequence_domain.hpp

@@ -28,6 +28,8 @@ namespace libfqfft {
     FieldT arithmetic_generator;
     void do_precomputation();
 
+    static bool valid_for_size(const size_t m);
+
     arithmetic_sequence_domain(const size_t m);
 
     void FFT(std::vector<FieldT> &a);

libfqfft/evaluation_domain/domains/arithmetic_sequence_domain.tcc

@@ -23,6 +23,20 @@
 
 namespace libfqfft {
 
+template<typename FieldT>
+bool arithmetic_sequence_domain<FieldT>::valid_for_size(const size_t m)
+{
+  if (m <= 1) {
+    return false;
+  }
+
+  if (FieldT::arithmetic_generator() == FieldT::zero()) {
+    return false;
+  }
+
+  return true;
+}
+
 template<typename FieldT>
 arithmetic_sequence_domain<FieldT>::arithmetic_sequence_domain(const size_t m) : evaluation_domain<FieldT>(m)
 {
@@ -42,7 +56,7 @@ void arithmetic_sequence_domain<FieldT>::FFT(std::vector<FieldT> &a)
 
   /* Monomial to Newton */
   monomial_to_newton_basis(a, this->subproduct_tree, this->m);
-  
+
   /* Newton to Evaluation */
   std::vector<FieldT> S(this->m); /* i! * arithmetic_generator */
   S[0] = FieldT::one();
@@ -70,7 +84,7 @@ template<typename FieldT>
 void arithmetic_sequence_domain<FieldT>::iFFT(std::vector<FieldT> &a)
 {
   if (a.size() != this->m) throw DomainSizeException("arithmetic: expected a.size() == this->m");
-  
+
   if (!this->precomputation_sentinel) do_precomputation();
 
   /* Interpolation to Newton */
@@ -152,7 +166,7 @@ std::vector<FieldT> arithmetic_sequence_domain<FieldT>::evaluate_all_lagrange_po
 
   std::vector<FieldT> w(this->m);
   w[0] = g_vanish.inverse() * (this->arithmetic_generator^(this->m-1));
-  
+
   l[0] = l_vanish * l[0].inverse() * w[0];
   for (size_t i = 1; i < this->m; i++)
   {

libfqfft/evaluation_domain/domains/basic_radix2_domain.hpp

@@ -26,6 +26,8 @@ class basic_radix2_domain : public evaluation_domain<FieldT> {
 
     FieldT omega;
 
+    static bool valid_for_size(const size_t m);
+
     basic_radix2_domain(const size_t m);
 
     void FFT(std::vector<FieldT> &a);

libfqfft/evaluation_domain/domains/basic_radix2_domain.tcc

@@ -22,6 +22,20 @@
 
 namespace libfqfft {
 
+template<typename FieldT>
+bool basic_radix2_domain<FieldT>::valid_for_size(const size_t m)
+{
+    if (m <= 1) {
+        return false;
+    }
+
+    if (!libff::has_root_of_unity<FieldT>(m)) {
+        return false;
+    }
+
+    return true;
+}
+
 template<typename FieldT>
 basic_radix2_domain<FieldT>::basic_radix2_domain(const size_t m) : evaluation_domain<FieldT>(m)
 {

libfqfft/evaluation_domain/domains/extended_radix2_domain.hpp

@@ -27,6 +27,8 @@ class extended_radix2_domain : public evaluation_domain<FieldT> {
     FieldT omega;
     FieldT shift;
 
+    static bool valid_for_size(const size_t m);
+
     extended_radix2_domain(const size_t m);
 
     void FFT(std::vector<FieldT> &a);

libfqfft/evaluation_domain/domains/extended_radix2_domain.tcc

@@ -17,6 +17,32 @@
 
 namespace libfqfft {
 
+template<typename FieldT>
+bool extended_radix2_domain<FieldT>::valid_for_size(const size_t m)
+{
+    if (m <= 1) {
+        return false;
+    }
+
+    // Will `get_root_of_unity` throw?
+    if (!std::is_same<FieldT, libff::Double>::value)
+    {
+        const size_t logm = libff::log2(m);
+
+        if (logm != (FieldT::s + 1)) {
+            return false;
+        }
+    }
+
+    size_t small_m = m / 2;
+
+    if (!libff::has_root_of_unity<FieldT>(small_m)) {
+        return false;
+    }
+
+    return true;
+}
+
 template<typename FieldT>
 extended_radix2_domain<FieldT>::extended_radix2_domain(const size_t m) : evaluation_domain<FieldT>(m)
 {

libfqfft/evaluation_domain/domains/geometric_sequence_domain.hpp

@@ -27,6 +27,8 @@ namespace libfqfft {
     std::vector<FieldT> geometric_triangular_sequence;
     void do_precomputation();
 
+    static bool valid_for_size(const size_t m);
+
     geometric_sequence_domain(const size_t m);
 
     void FFT(std::vector<FieldT> &a);

libfqfft/evaluation_domain/domains/geometric_sequence_domain.tcc

@@ -23,19 +23,33 @@
 
 namespace libfqfft {
 
+template<typename FieldT>
+bool geometric_sequence_domain<FieldT>::valid_for_size(const size_t m)
+{
+  if (m <= 1) {
+      return false;
+  }
+
+  if (FieldT::geometric_generator() == FieldT::zero()) {
+      return false;
+  }
+
+  return true;
+}
+
 template<typename FieldT>
 geometric_sequence_domain<FieldT>::geometric_sequence_domain(const size_t m) : evaluation_domain<FieldT>(m)
 {
   if (m <= 1) throw InvalidSizeException("geometric(): expected m > 1");
   if (FieldT::geometric_generator() == FieldT::zero())
     throw InvalidSizeException("geometric(): expected FieldT::geometric_generator() != FieldT::zero()");
-  
+
   precomputation_sentinel = 0;
 }
 
 template<typename FieldT>
 void geometric_sequence_domain<FieldT>::FFT(std::vector<FieldT> &a)
-{ 
+{
   if (a.size() != this->m) throw DomainSizeException("geometric: expected a.size() == this->m");
 
   if (!this->precomputation_sentinel) do_precomputation();
@@ -71,7 +85,7 @@ template<typename FieldT>
 void geometric_sequence_domain<FieldT>::iFFT(std::vector<FieldT> &a)
 {
   if (a.size() != this->m) throw DomainSizeException("geometric: expected a.size() == this->m");
-  
+
   if (!this->precomputation_sentinel) do_precomputation();
 
   /* Interpolation to Newton */

libfqfft/evaluation_domain/domains/step_radix2_domain.hpp

@@ -29,6 +29,8 @@ class step_radix2_domain : public evaluation_domain<FieldT> {
     FieldT big_omega;
     FieldT small_omega;
 
+    static bool valid_for_size(const size_t m);
+
     step_radix2_domain(const size_t m);
 
     void FFT(std::vector<FieldT> &a);

libfqfft/evaluation_domain/domains/step_radix2_domain.tcc

@@ -17,6 +17,33 @@
 
 namespace libfqfft {
 
+template<typename FieldT>
+bool step_radix2_domain<FieldT>::valid_for_size(const size_t m)
+{
+    if (m <= 1) {
+        return false;
+    }
+
+    const size_t big_m = 1ul<<(libff::log2(m)-1);
+    const size_t small_m = m - big_m;
+
+    if (small_m != 1ul<<libff::log2(small_m)) {
+        return false;
+    }
+
+    // omega
+    if (!libff::has_root_of_unity<FieldT>(1ul<<libff::log2(m))) {
+        return false;
+    }
+
+    // small_omega
+    if (!libff::has_root_of_unity<FieldT>(1ul<<libff::log2(small_m))) {
+        return false;
+    }
+
+    return true;
+}
+
 template<typename FieldT>
 step_radix2_domain<FieldT>::step_radix2_domain(const size_t m) : evaluation_domain<FieldT>(m)
 {
@@ -30,7 +57,7 @@ step_radix2_domain<FieldT>::step_radix2_domain(const size_t m) : evaluation_doma
 
     try { omega = libff::get_root_of_unity<FieldT>(1ul<<libff::log2(m)); }
     catch (const std::invalid_argument& e) { throw DomainSizeException(e.what()); }
-    
+
     big_omega = omega.squared();
     small_omega = libff::get_root_of_unity<FieldT>(small_m);
 }

libfqfft/evaluation_domain/evaluation_domain.hpp

@@ -27,6 +27,7 @@
 #define EVALUATION_DOMAIN_HPP_
 
 #include <vector>
+#include <libff/common/double.hpp>
 
 namespace libfqfft {
 

libfqfft/evaluation_domain/get_evaluation_domain.tcc

@@ -38,15 +38,33 @@ std::shared_ptr<evaluation_domain<FieldT> > get_evaluation_domain(const size_t m
     const size_t small = min_size - big;
     const size_t rounded_small = (1ul<<libff::log2(small));
 
-    try { result.reset(new basic_radix2_domain<FieldT>(min_size)); }
-    catch(...) { try { result.reset(new extended_radix2_domain<FieldT>(min_size)); }
-    catch(...) { try { result.reset(new step_radix2_domain<FieldT>(min_size)); }
-    catch(...) { try { result.reset(new basic_radix2_domain<FieldT>(big + rounded_small)); }
-    catch(...) { try { result.reset(new extended_radix2_domain<FieldT>(big + rounded_small)); }
-    catch(...) { try { result.reset(new step_radix2_domain<FieldT>(big + rounded_small)); }
-    catch(...) { try { result.reset(new geometric_sequence_domain<FieldT>(min_size)); }
-    catch(...) { try { result.reset(new arithmetic_sequence_domain<FieldT>(min_size)); }
-    catch(...) { throw DomainSizeException("get_evaluation_domain: no matching domain"); }}}}}}}}
+    if (basic_radix2_domain<FieldT>::valid_for_size(min_size)) {
+        result.reset(new basic_radix2_domain<FieldT>(min_size));
+    }
+    else if (extended_radix2_domain<FieldT>::valid_for_size(min_size)) {
+        result.reset(new extended_radix2_domain<FieldT>(min_size));
+    }
+    else if (step_radix2_domain<FieldT>::valid_for_size(min_size)) {
+        result.reset(new step_radix2_domain<FieldT>(min_size));
+    }
+    else if (basic_radix2_domain<FieldT>::valid_for_size(big + rounded_small)) {
+        result.reset(new basic_radix2_domain<FieldT>(big + rounded_small));
+    }
+    else if (extended_radix2_domain<FieldT>::valid_for_size(big + rounded_small)) {
+        result.reset(new extended_radix2_domain<FieldT>(big + rounded_small));
+    }
+    else if (step_radix2_domain<FieldT>::valid_for_size(big + rounded_small)) {
+        result.reset(new step_radix2_domain<FieldT>(big + rounded_small));
+    }
+    else if (geometric_sequence_domain<FieldT>::valid_for_size(min_size)) {
+        result.reset(new geometric_sequence_domain<FieldT>(min_size));
+    }
+    else if (arithmetic_sequence_domain<FieldT>::valid_for_size(min_size)) {
+        result.reset(new arithmetic_sequence_domain<FieldT>(min_size));
+    }
+    else {
+        throw DomainSizeException("get_evaluation_domain: no matching domain");
+    }
 
     return result;
 }