Merge branch 'develop' into 'master'

Develop

See merge request !7

README.md

@@ -17,3 +17,4 @@ Features
   transforms
 - does not have persistent transform plans, which makes the interface simpler
 - supports prime-length transforms without degrading to O(N**2) performance
+- Has optional OpenMP support for multidimensional transforms

pocketfft_hdronly.h

@@ -1099,9 +1099,13 @@ template<typename T0> class rfftp
       { fact.push_back({factor, nullptr, nullptr}); }
 
 #define WA(x,i) wa[(i)+(x)*(ido-1)]
-#define PM(a,b,c,d) { a=c+d; b=c-d; }
+template<typename T> inline void PM(T &a, T &b, T c, T d)
+  { a=c+d; b=c-d; }
+
 /* (a+ib) = conj(c+id) * (e+if) */
-#define MULPM(a,b,c,d,e,f) { a=c*e+d*f; b=c*f-d*e; }
+template<typename T1, typename T2, typename T3> inline void MULPM
+  (T1 &a, T1 &b, T2 c, T2 d, T3 e, T3 f)
+  {  a=c*e+d*f; b=c*f-d*e; }
 
 #define CC(a,b,c) cc[(a)+ido*((b)+l1*(c))]
 #define CH(a,b,c) ch[(a)+ido*((b)+cdim*(c))]
@@ -1112,7 +1116,7 @@ template<typename T> void radf2 (size_t ido, size_t l1,
   constexpr size_t cdim=2;
 
   for (size_t k=0; k<l1; k++)
-    PM (CH(0,0,k),CH(ido-1,1,k),CC(0,k,0),CC(0,k,1))
+    PM (CH(0,0,k),CH(ido-1,1,k),CC(0,k,0),CC(0,k,1));
   if ((ido&1)==0)
     for (size_t k=0; k<l1; k++)
       {
@@ -1125,9 +1129,9 @@ template<typename T> void radf2 (size_t ido, size_t l1,
       {
       size_t ic=ido-i;
       T tr2, ti2;
-      MULPM (tr2,ti2,WA(0,i-2),WA(0,i-1),CC(i-1,k,1),CC(i,k,1))
-      PM (CH(i-1,0,k),CH(ic-1,1,k),CC(i-1,k,0),tr2)
-      PM (CH(i  ,0,k),CH(ic  ,1,k),ti2,CC(i  ,k,0))
+      MULPM (tr2,ti2,WA(0,i-2),WA(0,i-1),CC(i-1,k,1),CC(i,k,1));
+      PM (CH(i-1,0,k),CH(ic-1,1,k),CC(i-1,k,0),tr2);
+      PM (CH(i  ,0,k),CH(ic  ,1,k),ti2,CC(i  ,k,0));
       }
   }
 
@@ -1150,8 +1154,8 @@ template<typename T> void radf3(size_t ido, size_t l1,
       {
       size_t ic=ido-i;
       T di2, di3, dr2, dr3;
-      MULPM (dr2,di2,WA(0,i-2),WA(0,i-1),CC(i-1,k,1),CC(i,k,1)) // d2=conj(WA0)*CC1
-      MULPM (dr3,di3,WA(1,i-2),WA(1,i-1),CC(i-1,k,2),CC(i,k,2)) // d3=conj(WA1)*CC2
+      MULPM (dr2,di2,WA(0,i-2),WA(0,i-1),CC(i-1,k,1),CC(i,k,1)); // d2=conj(WA0)*CC1
+      MULPM (dr3,di3,WA(1,i-2),WA(1,i-1),CC(i-1,k,2),CC(i,k,2)); // d3=conj(WA1)*CC2
       T cr2=dr2+dr3; // c add
       T ci2=di2+di3;
       CH(i-1,0,k) = CC(i-1,k,0)+cr2; // c add
@@ -1160,8 +1164,8 @@ template<typename T> void radf3(size_t ido, size_t l1,
       T ti2 = CC(i  ,k,0)+taur*ci2;
       T tr3 = taui*(di2-di3);  // t3 = taui*i*(d3-d2)?
       T ti3 = taui*(dr3-dr2);
-      PM(CH(i-1,2,k),CH(ic-1,1,k),tr2,tr3) // PM(i) = t2+t3
-      PM(CH(i  ,2,k),CH(ic  ,1,k),ti3,ti2) // PM(ic) = conj(t2-t3)
+      PM(CH(i-1,2,k),CH(ic-1,1,k),tr2,tr3); // PM(i) = t2+t3
+      PM(CH(i  ,2,k),CH(ic  ,1,k),ti3,ti2); // PM(ic) = conj(t2-t3)
       }
   }
 
@@ -1174,17 +1178,17 @@ template<typename T> void radf4(size_t ido, size_t l1,
   for (size_t k=0; k<l1; k++)
     {
     T tr1,tr2;
-    PM (tr1,CH(0,2,k),CC(0,k,3),CC(0,k,1))
-    PM (tr2,CH(ido-1,1,k),CC(0,k,0),CC(0,k,2))
-    PM (CH(0,0,k),CH(ido-1,3,k),tr2,tr1)
+    PM (tr1,CH(0,2,k),CC(0,k,3),CC(0,k,1));
+    PM (tr2,CH(ido-1,1,k),CC(0,k,0),CC(0,k,2));
+    PM (CH(0,0,k),CH(ido-1,3,k),tr2,tr1);
     }
   if ((ido&1)==0)
     for (size_t k=0; k<l1; k++)
       {
       T ti1=-hsqt2*(CC(ido-1,k,1)+CC(ido-1,k,3));
       T tr1= hsqt2*(CC(ido-1,k,1)-CC(ido-1,k,3));
-      PM (CH(ido-1,0,k),CH(ido-1,2,k),CC(ido-1,k,0),tr1)
-      PM (CH(    0,3,k),CH(    0,1,k),ti1,CC(ido-1,k,2))
+      PM (CH(ido-1,0,k),CH(ido-1,2,k),CC(ido-1,k,0),tr1);
+      PM (CH(    0,3,k),CH(    0,1,k),ti1,CC(ido-1,k,2));
       }
   if (ido<=2) return;
   for (size_t k=0; k<l1; k++)
@@ -1192,17 +1196,17 @@ template<typename T> void radf4(size_t ido, size_t l1,
       {
       size_t ic=ido-i;
       T ci2, ci3, ci4, cr2, cr3, cr4, ti1, ti2, ti3, ti4, tr1, tr2, tr3, tr4;
-      MULPM(cr2,ci2,WA(0,i-2),WA(0,i-1),CC(i-1,k,1),CC(i,k,1))
-      MULPM(cr3,ci3,WA(1,i-2),WA(1,i-1),CC(i-1,k,2),CC(i,k,2))
-      MULPM(cr4,ci4,WA(2,i-2),WA(2,i-1),CC(i-1,k,3),CC(i,k,3))
-      PM(tr1,tr4,cr4,cr2)
-      PM(ti1,ti4,ci2,ci4)
-      PM(tr2,tr3,CC(i-1,k,0),cr3)
-      PM(ti2,ti3,CC(i  ,k,0),ci3)
-      PM(CH(i-1,0,k),CH(ic-1,3,k),tr2,tr1)
-      PM(CH(i  ,0,k),CH(ic  ,3,k),ti1,ti2)
-      PM(CH(i-1,2,k),CH(ic-1,1,k),tr3,ti4)
-      PM(CH(i  ,2,k),CH(ic  ,1,k),tr4,ti3)
+      MULPM(cr2,ci2,WA(0,i-2),WA(0,i-1),CC(i-1,k,1),CC(i,k,1));
+      MULPM(cr3,ci3,WA(1,i-2),WA(1,i-1),CC(i-1,k,2),CC(i,k,2));
+      MULPM(cr4,ci4,WA(2,i-2),WA(2,i-1),CC(i-1,k,3),CC(i,k,3));
+      PM(tr1,tr4,cr4,cr2);
+      PM(ti1,ti4,ci2,ci4);
+      PM(tr2,tr3,CC(i-1,k,0),cr3);
+      PM(ti2,ti3,CC(i  ,k,0),ci3);
+      PM(CH(i-1,0,k),CH(ic-1,3,k),tr2,tr1);
+      PM(CH(i  ,0,k),CH(ic  ,3,k),ti1,ti2);
+      PM(CH(i-1,2,k),CH(ic-1,1,k),tr3,ti4);
+      PM(CH(i  ,2,k),CH(ic  ,1,k),tr4,ti3);
       }
   }
 
@@ -1218,8 +1222,8 @@ template<typename T> void radf5(size_t ido, size_t l1,
   for (size_t k=0; k<l1; k++)
     {
     T cr2, cr3, ci4, ci5;
-    PM (cr2,ci5,CC(0,k,4),CC(0,k,1))
-    PM (cr3,ci4,CC(0,k,3),CC(0,k,2))
+    PM (cr2,ci5,CC(0,k,4),CC(0,k,1));
+    PM (cr3,ci4,CC(0,k,3),CC(0,k,2));
     CH(0,0,k)=CC(0,k,0)+cr2+cr3;
     CH(ido-1,1,k)=CC(0,k,0)+tr11*cr2+tr12*cr3;
     CH(0,2,k)=ti11*ci5+ti12*ci4;
@@ -1233,26 +1237,26 @@ template<typename T> void radf5(size_t ido, size_t l1,
       T ci2, di2, ci4, ci5, di3, di4, di5, ci3, cr2, cr3, dr2, dr3,
         dr4, dr5, cr5, cr4, ti2, ti3, ti5, ti4, tr2, tr3, tr4, tr5;
       size_t ic=ido-i;
-      MULPM (dr2,di2,WA(0,i-2),WA(0,i-1),CC(i-1,k,1),CC(i,k,1))
-      MULPM (dr3,di3,WA(1,i-2),WA(1,i-1),CC(i-1,k,2),CC(i,k,2))
-      MULPM (dr4,di4,WA(2,i-2),WA(2,i-1),CC(i-1,k,3),CC(i,k,3))
-      MULPM (dr5,di5,WA(3,i-2),WA(3,i-1),CC(i-1,k,4),CC(i,k,4))
-      PM(cr2,ci5,dr5,dr2)
-      PM(ci2,cr5,di2,di5)
-      PM(cr3,ci4,dr4,dr3)
-      PM(ci3,cr4,di3,di4)
+      MULPM (dr2,di2,WA(0,i-2),WA(0,i-1),CC(i-1,k,1),CC(i,k,1));
+      MULPM (dr3,di3,WA(1,i-2),WA(1,i-1),CC(i-1,k,2),CC(i,k,2));
+      MULPM (dr4,di4,WA(2,i-2),WA(2,i-1),CC(i-1,k,3),CC(i,k,3));
+      MULPM (dr5,di5,WA(3,i-2),WA(3,i-1),CC(i-1,k,4),CC(i,k,4));
+      PM(cr2,ci5,dr5,dr2);
+      PM(ci2,cr5,di2,di5);
+      PM(cr3,ci4,dr4,dr3);
+      PM(ci3,cr4,di3,di4);
       CH(i-1,0,k)=CC(i-1,k,0)+cr2+cr3;
       CH(i  ,0,k)=CC(i  ,k,0)+ci2+ci3;
       tr2=CC(i-1,k,0)+tr11*cr2+tr12*cr3;
       ti2=CC(i  ,k,0)+tr11*ci2+tr12*ci3;
       tr3=CC(i-1,k,0)+tr12*cr2+tr11*cr3;
       ti3=CC(i  ,k,0)+tr12*ci2+tr11*ci3;
-      MULPM(tr5,tr4,cr5,cr4,ti11,ti12)
-      MULPM(ti5,ti4,ci5,ci4,ti11,ti12)
-      PM(CH(i-1,2,k),CH(ic-1,1,k),tr2,tr5)
-      PM(CH(i  ,2,k),CH(ic  ,1,k),ti5,ti2)
-      PM(CH(i-1,4,k),CH(ic-1,3,k),tr3,tr4)
-      PM(CH(i  ,4,k),CH(ic  ,3,k),ti4,ti3)
+      MULPM(tr5,tr4,cr5,cr4,ti11,ti12);
+      MULPM(ti5,ti4,ci5,ci4,ti11,ti12);
+      PM(CH(i-1,2,k),CH(ic-1,1,k),tr2,tr5);
+      PM(CH(i  ,2,k),CH(ic  ,1,k),ti5,ti2);
+      PM(CH(i-1,4,k),CH(ic-1,3,k),tr3,tr4);
+      PM(CH(i  ,4,k),CH(ic  ,3,k),ti4,ti3);
       }
   }
 
@@ -1414,7 +1418,7 @@ template<typename T> void radb2(size_t ido, size_t l1, const T * restrict cc,
   constexpr size_t cdim=2;
 
   for (size_t k=0; k<l1; k++)
-    PM (CH(0,k,0),CH(0,k,1),CC(0,0,k),CC(ido-1,1,k))
+    PM (CH(0,k,0),CH(0,k,1),CC(0,0,k),CC(ido-1,1,k));
   if ((ido&1)==0)
     for (size_t k=0; k<l1; k++)
       {
@@ -1427,9 +1431,9 @@ template<typename T> void radb2(size_t ido, size_t l1, const T * restrict cc,
       {
       size_t ic=ido-i;
       T ti2, tr2;
-      PM (CH(i-1,k,0),tr2,CC(i-1,0,k),CC(ic-1,1,k))
-      PM (ti2,CH(i  ,k,0),CC(i  ,0,k),CC(ic  ,1,k))
-      MULPM (CH(i,k,1),CH(i-1,k,1),WA(0,i-2),WA(0,i-1),ti2,tr2)
+      PM (CH(i-1,k,0),tr2,CC(i-1,0,k),CC(ic-1,1,k));
+      PM (ti2,CH(i  ,k,0),CC(i  ,0,k),CC(ic  ,1,k));
+      MULPM (CH(i,k,1),CH(i-1,k,1),WA(0,i-2),WA(0,i-1),ti2,tr2);
       }
   }
 
@@ -1461,10 +1465,10 @@ template<typename T> void radb3(size_t ido, size_t l1,
       T cr3=taui*(CC(i-1,2,k)-CC(ic-1,1,k));// c3=taui*(CC(i)-conj(CC(ic)))
       T ci3=taui*(CC(i  ,2,k)+CC(ic  ,1,k));
       T di2, di3, dr2, dr3;
-      PM(dr3,dr2,cr2,ci3) // d2= (cr2-ci3, ci2+cr3) = c2+i*c3
-      PM(di2,di3,ci2,cr3) // d3= (cr2+ci3, ci2-cr3) = c2-i*c3
-      MULPM(CH(i,k,1),CH(i-1,k,1),WA(0,i-2),WA(0,i-1),di2,dr2) // ch = WA*d2
-      MULPM(CH(i,k,2),CH(i-1,k,2),WA(1,i-2),WA(1,i-1),di3,dr3)
+      PM(dr3,dr2,cr2,ci3); // d2= (cr2-ci3, ci2+cr3) = c2+i*c3
+      PM(di2,di3,ci2,cr3); // d3= (cr2+ci3, ci2-cr3) = c2-i*c3
+      MULPM(CH(i,k,1),CH(i-1,k,1),WA(0,i-2),WA(0,i-1),di2,dr2); // ch = WA*d2
+      MULPM(CH(i,k,2),CH(i-1,k,2),WA(1,i-2),WA(1,i-1),di3,dr3);
       }
   }
 
@@ -1477,18 +1481,18 @@ template<typename T> void radb4(size_t ido, size_t l1,
   for (size_t k=0; k<l1; k++)
     {
     T tr1, tr2;
-    PM (tr2,tr1,CC(0,0,k),CC(ido-1,3,k))
+    PM (tr2,tr1,CC(0,0,k),CC(ido-1,3,k));
     T tr3=2*CC(ido-1,1,k);
     T tr4=2*CC(0,2,k);
-    PM (CH(0,k,0),CH(0,k,2),tr2,tr3)
-    PM (CH(0,k,3),CH(0,k,1),tr1,tr4)
+    PM (CH(0,k,0),CH(0,k,2),tr2,tr3);
+    PM (CH(0,k,3),CH(0,k,1),tr1,tr4);
     }
   if ((ido&1)==0)
     for (size_t k=0; k<l1; k++)
       {
       T tr1,tr2,ti1,ti2;
-      PM (ti1,ti2,CC(0    ,3,k),CC(0    ,1,k))
-      PM (tr2,tr1,CC(ido-1,0,k),CC(ido-1,2,k))
+      PM (ti1,ti2,CC(0    ,3,k),CC(0    ,1,k));
+      PM (tr2,tr1,CC(ido-1,0,k),CC(ido-1,2,k));
       CH(ido-1,k,0)=tr2+tr2;
       CH(ido-1,k,1)=sqrt2*(tr1-ti1);
       CH(ido-1,k,2)=ti2+ti2;
@@ -1500,17 +1504,17 @@ template<typename T> void radb4(size_t ido, size_t l1,
       {
       T ci2, ci3, ci4, cr2, cr3, cr4, ti1, ti2, ti3, ti4, tr1, tr2, tr3, tr4;
       size_t ic=ido-i;
-      PM (tr2,tr1,CC(i-1,0,k),CC(ic-1,3,k))
-      PM (ti1,ti2,CC(i  ,0,k),CC(ic  ,3,k))
-      PM (tr4,ti3,CC(i  ,2,k),CC(ic  ,1,k))
-      PM (tr3,ti4,CC(i-1,2,k),CC(ic-1,1,k))
-      PM (CH(i-1,k,0),cr3,tr2,tr3)
-      PM (CH(i  ,k,0),ci3,ti2,ti3)
-      PM (cr4,cr2,tr1,tr4)
-      PM (ci2,ci4,ti1,ti4)
-      MULPM (CH(i,k,1),CH(i-1,k,1),WA(0,i-2),WA(0,i-1),ci2,cr2)
-      MULPM (CH(i,k,2),CH(i-1,k,2),WA(1,i-2),WA(1,i-1),ci3,cr3)
-      MULPM (CH(i,k,3),CH(i-1,k,3),WA(2,i-2),WA(2,i-1),ci4,cr4)
+      PM (tr2,tr1,CC(i-1,0,k),CC(ic-1,3,k));
+      PM (ti1,ti2,CC(i  ,0,k),CC(ic  ,3,k));
+      PM (tr4,ti3,CC(i  ,2,k),CC(ic  ,1,k));
+      PM (tr3,ti4,CC(i-1,2,k),CC(ic-1,1,k));
+      PM (CH(i-1,k,0),cr3,tr2,tr3);
+      PM (CH(i  ,k,0),ci3,ti2,ti3);
+      PM (cr4,cr2,tr1,tr4);
+      PM (ci2,ci4,ti1,ti4);
+      MULPM (CH(i,k,1),CH(i-1,k,1),WA(0,i-2),WA(0,i-1),ci2,cr2);
+      MULPM (CH(i,k,2),CH(i-1,k,2),WA(1,i-2),WA(1,i-1),ci3,cr3);
+      MULPM (CH(i,k,3),CH(i-1,k,3),WA(2,i-2),WA(2,i-1),ci4,cr4);
       }
   }
 
@@ -1533,9 +1537,9 @@ template<typename T> void radb5(size_t ido, size_t l1,
     T cr2=CC(0,0,k)+tr11*tr2+tr12*tr3;
     T cr3=CC(0,0,k)+tr12*tr2+tr11*tr3;
     T ci4, ci5;
-    MULPM(ci5,ci4,ti5,ti4,ti11,ti12)
-    PM(CH(0,k,4),CH(0,k,1),cr2,ci5)
-    PM(CH(0,k,3),CH(0,k,2),cr3,ci4)
+    MULPM(ci5,ci4,ti5,ti4,ti11,ti12);
+    PM(CH(0,k,4),CH(0,k,1),cr2,ci5);
+    PM(CH(0,k,3),CH(0,k,2),cr3,ci4);
     }
   if (ido==1) return;
   for (size_t k=0; k<l1;++k)
@@ -1543,10 +1547,10 @@ template<typename T> void radb5(size_t ido, size_t l1,
       {
       size_t ic=ido-i;
       T tr2, tr3, tr4, tr5, ti2, ti3, ti4, ti5;
-      PM(tr2,tr5,CC(i-1,2,k),CC(ic-1,1,k))
-      PM(ti5,ti2,CC(i  ,2,k),CC(ic  ,1,k))
-      PM(tr3,tr4,CC(i-1,4,k),CC(ic-1,3,k))
-      PM(ti4,ti3,CC(i  ,4,k),CC(ic  ,3,k))
+      PM(tr2,tr5,CC(i-1,2,k),CC(ic-1,1,k));
+      PM(ti5,ti2,CC(i  ,2,k),CC(ic  ,1,k));
+      PM(tr3,tr4,CC(i-1,4,k),CC(ic-1,3,k));
+      PM(ti4,ti3,CC(i  ,4,k),CC(ic  ,3,k));
       CH(i-1,k,0)=CC(i-1,0,k)+tr2+tr3;
       CH(i  ,k,0)=CC(i  ,0,k)+ti2+ti3;
       T cr2=CC(i-1,0,k)+tr11*tr2+tr12*tr3;
@@ -1554,17 +1558,17 @@ template<typename T> void radb5(size_t ido, size_t l1,
       T cr3=CC(i-1,0,k)+tr12*tr2+tr11*tr3;
       T ci3=CC(i  ,0,k)+tr12*ti2+tr11*ti3;
       T ci4, ci5, cr5, cr4;
-      MULPM(cr5,cr4,tr5,tr4,ti11,ti12)
-      MULPM(ci5,ci4,ti5,ti4,ti11,ti12)
+      MULPM(cr5,cr4,tr5,tr4,ti11,ti12);
+      MULPM(ci5,ci4,ti5,ti4,ti11,ti12);
       T dr2, dr3, dr4, dr5, di2, di3, di4, di5;
-      PM(dr4,dr3,cr3,ci4)
-      PM(di3,di4,ci3,cr4)
-      PM(dr5,dr2,cr2,ci5)
-      PM(di2,di5,ci2,cr5)
-      MULPM(CH(i,k,1),CH(i-1,k,1),WA(0,i-2),WA(0,i-1),di2,dr2)
-      MULPM(CH(i,k,2),CH(i-1,k,2),WA(1,i-2),WA(1,i-1),di3,dr3)
-      MULPM(CH(i,k,3),CH(i-1,k,3),WA(2,i-2),WA(2,i-1),di4,dr4)
-      MULPM(CH(i,k,4),CH(i-1,k,4),WA(3,i-2),WA(3,i-1),di5,dr5)
+      PM(dr4,dr3,cr3,ci4);
+      PM(di3,di4,ci3,cr4);
+      PM(dr5,dr2,cr2,ci5);
+      PM(di2,di5,ci2,cr5);
+      MULPM(CH(i,k,1),CH(i-1,k,1),WA(0,i-2),WA(0,i-1),di2,dr2);
+      MULPM(CH(i,k,2),CH(i-1,k,2),WA(1,i-2),WA(1,i-1),di3,dr3);
+      MULPM(CH(i,k,3),CH(i-1,k,3),WA(2,i-2),WA(2,i-1),di4,dr4);
+      MULPM(CH(i,k,4),CH(i-1,k,4),WA(3,i-2),WA(3,i-1),di5,dr5);
       }
   }
 
@@ -1709,8 +1713,6 @@ template<typename T> void radbg(size_t ido, size_t ip, size_t l1,
 #undef CH
 #undef CC
 
-#undef MULPM
-#undef PM
 #undef WA
 
     template<typename T> void copy_and_norm(T *c, T *p1, size_t n, T0 fct)
@@ -2212,9 +2214,15 @@ template<typename T> arr<char> alloc_tmp(const shape_t &shape,
   return arr<char>(tmpsize*elemsize);
   }
 
+#ifdef POCKETFFT_OPENMP
+#define POCKETFFT_NTHREADS nthreads
+#else
+#define POCKETFFT_NTHREADS
+#endif
+
 template<typename T> NOINLINE void general_c(
   const ndarr<cmplx<T>> &in, ndarr<cmplx<T>> &out,
-  const shape_t &axes, bool forward, T fct, size_t nthreads=1)
+  const shape_t &axes, bool forward, T fct, size_t POCKETFFT_NTHREADS)
   {
   unique_ptr<pocketfft_c<T>> plan;
 
@@ -2277,7 +2285,7 @@ template<typename T> NOINLINE void general_c(
 
 template<typename T> NOINLINE void general_hartley(
   const ndarr<T> &in, ndarr<T> &out, const shape_t &axes, T fct,
-  size_t nthreads=1)
+  size_t POCKETFFT_NTHREADS)
   {
   unique_ptr<pocketfft_r<T>> plan;
 
@@ -2341,7 +2349,7 @@ template<typename T> NOINLINE void general_hartley(
 
 template<typename T> NOINLINE void general_r2c(
   const ndarr<T> &in, ndarr<cmplx<T>> &out, size_t axis, T fct,
-  size_t nthreads=1)
+  size_t POCKETFFT_NTHREADS)
   {
   pocketfft_r<T> plan(in.shape(axis));
   constexpr auto vlen = VTYPE<T>::vlen;
@@ -2392,7 +2400,7 @@ template<typename T> NOINLINE void general_r2c(
   }
 template<typename T> NOINLINE void general_c2r(
   const ndarr<cmplx<T>> &in, ndarr<T> &out, size_t axis, T fct,
-  size_t nthreads=1)
+  size_t POCKETFFT_NTHREADS)
   {
   pocketfft_r<T> plan(out.shape(axis));
   constexpr auto vlen = VTYPE<T>::vlen;
@@ -2448,7 +2456,7 @@ template<typename T> NOINLINE void general_c2r(
 
 template<typename T> NOINLINE void general_r(
   const ndarr<T> &in, ndarr<T> &out, size_t axis, bool forward, T fct,
-  size_t nthreads=1)
+  size_t POCKETFFT_NTHREADS)
   {
   constexpr auto vlen = VTYPE<T>::vlen;
   size_t len=in.shape(axis);
@@ -2501,6 +2509,7 @@ template<typename T> NOINLINE void general_r(
 } // end of parallel region
   }
 
+#undef POCKETFFT_NTHREADS
 #undef HAVE_VECSUPPORT
 
 template<typename T> void c2c(const shape_t &shape, const stride_t &stride_in,

setup.py

-from setuptools import setup, Extension, Distribution
-import setuptools.command.build_ext
+from setuptools import setup, Extension
 
 import sys
 import sysconfig
-import os
 import os.path
 import distutils.sysconfig
-import itertools
-from glob import iglob
-
-
-def _get_distutils_build_directory():
-    """
-    Returns the directory distutils uses to build its files.
-    We need this directory since we build extensions which have to link
-    other ones.
-    """
-    pattern = "lib.{platform}-{major}.{minor}"
-    return os.path.join(
-        'build', pattern.format(platform=sysconfig.get_platform(),
-                                major=sys.version_info[0],
-                                minor=sys.version_info[1]))
 
 
 class _deferred_pybind11_include(object):
@@ -32,59 +15,31 @@ class _deferred_pybind11_include(object):
         return pybind11.get_include(self.user)
 
 
-def _remove_strict_prototype_option_from_distutils_config():
-    strict_prototypes = '-Wstrict-prototypes'
-    config = distutils.sysconfig.get_config_vars()
-    for key, value in config.items():
-        if strict_prototypes in str(value):
-            config[key] = config[key].replace(strict_prototypes, '')
-
-
-_remove_strict_prototype_option_from_distutils_config()
-
-
 extra_compile_args = []
-extra_cc_compile_args = []
 include_dirs = ['./', _deferred_pybind11_include(),
                 _deferred_pybind11_include(True)]
 
-library_dirs = [_get_distutils_build_directory()]
 python_module_link_args = []
 base_library_link_args = []
 
 if sys.platform == 'darwin':
-    extra_cc_compile_args.append('--std=c++11')
-    extra_cc_compile_args.append('--stdlib=libc++')
-    extra_compile_args.append('-mmacosx-version-min=10.9')
-
+    extra_compile_args += ['--std=c++11', '--stdlib=libc++', '-mmacosx-version-min=10.9']
     vars = distutils.sysconfig.get_config_vars()
     vars['LDSHARED'] = vars['LDSHARED'].replace('-bundle', '')
-    python_module_link_args.append('-bundle')
-    builder = setuptools.command.build_ext.build_ext(Distribution())
-    base_library_link_args.append('-dynamiclib')
+    python_module_link_args+=['-bundle']
+    base_library_link_args+=['-dynamiclib']
 else:
-    extra_compile_args += ['-march=native', '-O3', '-Wfatal-errors', '-Wno-ignored-attributes', '-DPOCKETFFT_OPENMP', '-fopenmp', '-Wfloat-conversion' ,'-Wsign-conversion', '-Wconversion' ,'-W', '-Wall']
-    python_module_link_args += ['-march=native']
-    extra_cc_compile_args.append('--std=c++11')
-    python_module_link_args.append("-Wl,-rpath,$ORIGIN")
-    python_module_link_args.append('-fopenmp')
-
-extra_cc_compile_args = extra_compile_args + extra_cc_compile_args
+    extra_compile_args += ['--std=c++11', '-march=native', '-O3', '-Wfatal-errors', '-Wno-ignored-attributes', '-DPOCKETFFT_OPENMP', '-fopenmp', '-Wfloat-conversion' ,'-Wsign-conversion', '-Wconversion' ,'-W', '-Wall']
+    python_module_link_args += ['-march=native', '-Wl,-rpath,$ORIGIN', '-fopenmp']
 
 
 def get_extension_modules():
-    extension_modules = []
-
-    pocketfft_sources = ['pypocketfft.cc']
     pocketfft_library = Extension('pypocketfft',
-                                sources=pocketfft_sources,
+                                sources=['pypocketfft.cc'],
                                 include_dirs=include_dirs,
-                                extra_compile_args=extra_cc_compile_args,
-                                extra_link_args=python_module_link_args,
-                                library_dirs=library_dirs)
-    extension_modules.append(pocketfft_library)
-
-    return extension_modules
+                                extra_compile_args=extra_compile_args,
+                                extra_link_args=python_module_link_args)
+    return [pocketfft_library]
 
 
 setup(name='pypocketfft',