Minor code cleanup

platforms/opencl/src/kernels/fft.cl

@@ -26,5 +26,4 @@ __kernel void execFFT(__global const real2* restrict in, __global real2* restric
         barrier(CLK_LOCAL_MEM_FENCE);
         COMPUTE_FFT
     }
-
 }

plugins/rpmd/platforms/cuda/src/CudaRpmdKernels.cpp

@@ -382,7 +382,6 @@ void CudaIntegrateRPMDStepKernel::copyToContext(int copy, ContextImpl& context)
 
 string CudaIntegrateRPMDStepKernel::createFFT(int size, const string& variable, bool forward) {
     stringstream source;
-    int unfactored = size;
     int stage = 0;
     int L = size;
     int m = 1;
@@ -398,16 +397,27 @@ string CudaIntegrateRPMDStepKernel::createFFT(int size, const string& variable,
 
     // Factor size, generating an appropriate block of code for each factor.
 
-    while (unfactored > 1) {
+    while (L > 1) {
         int input = stage%2;
         int output = 1-input;
+        int radix;
+        if (L%5 == 0)
+            radix = 5;
+        else if (L%4 == 0)
+            radix = 4;
+        else if (L%3 == 0)
+            radix = 3;
+        else if (L%2 == 0)
+            radix = 2;
+        else
+            throw OpenMMException("Illegal size for FFT: "+cu.intToString(size));
         source<<"{\n";
-        if (unfactored%5 == 0) {
-            L = L/5;
-            source<<"// Pass "<<(stage+1)<<" (radix 5)\n";
+        L = L/radix;
+        source<<"// Pass "<<(stage+1)<<" (radix "<<radix<<")\n";
         source<<"if (indexInBlock < "<<(L*m)<<") {\n";
         source<<"int i = indexInBlock;\n";
         source<<"int j = i/"<<m<<";\n";
+        if (radix == 5) {
             source<<"mixed3 c0r = real"<<input<<"[i];\n";
             source<<"mixed3 c0i = imag"<<input<<"[i];\n";
             source<<"mixed3 c1r = real"<<input<<"[i+"<<(L*m)<<"];\n";
@@ -451,16 +461,8 @@ string CudaIntegrateRPMDStepKernel::createFFT(int size, const string& variable,
             source<<"imag"<<output<<"[i+(4*j+3)*"<<m<<"] = "<<multImag<<"(w[j*"<<(3*size)<<"/"<<(5*L)<<"], d8r-d10r, d8i-d10i);\n";
             source<<"real"<<output<<"[i+(4*j+4)*"<<m<<"] = "<<multReal<<"(w[j*"<<(4*size)<<"/"<<(5*L)<<"], d7r-d9r, d7i-d9i);\n";
             source<<"imag"<<output<<"[i+(4*j+4)*"<<m<<"] = "<<multImag<<"(w[j*"<<(4*size)<<"/"<<(5*L)<<"], d7r-d9r, d7i-d9i);\n";
-            source<<"}\n";
-            m = m*5;
-            unfactored /= 5;
         }
-        else if (unfactored%4 == 0) {
-            L = L/4;
-            source<<"// Pass "<<(stage+1)<<" (radix 4)\n";
-            source<<"if (indexInBlock < "<<(L*m)<<") {\n";
-            source<<"int i = indexInBlock;\n";
-            source<<"int j = i/"<<m<<";\n";
+        else if (radix == 4) {
             source<<"mixed3 c0r = real"<<input<<"[i];\n";
             source<<"mixed3 c0i = imag"<<input<<"[i];\n";
             source<<"mixed3 c1r = real"<<input<<"[i+"<<(L*m)<<"];\n";
@@ -485,16 +487,8 @@ string CudaIntegrateRPMDStepKernel::createFFT(int size, const string& variable,
             source<<"imag"<<output<<"[i+(3*j+2)*"<<m<<"] = "<<multImag<<"(w[j*"<<(2*size)<<"/"<<(4*L)<<"], d0r-d2r, d0i-d2i);\n";
             source<<"real"<<output<<"[i+(3*j+3)*"<<m<<"] = "<<multReal<<"(w[j*"<<(3*size)<<"/"<<(4*L)<<"], d1r-d3r, d1i-d3i);\n";
             source<<"imag"<<output<<"[i+(3*j+3)*"<<m<<"] = "<<multImag<<"(w[j*"<<(3*size)<<"/"<<(4*L)<<"], d1r-d3r, d1i-d3i);\n";
-            source<<"}\n";
-            m = m*4;
-            unfactored /= 4;
         }
-        else if (unfactored%3 == 0) {
-            L = L/3;
-            source<<"// Pass "<<(stage+1)<<" (radix 3)\n";
-            source<<"if (indexInBlock < "<<(L*m)<<") {\n";
-            source<<"int i = indexInBlock;\n";
-            source<<"int j = i/"<<m<<";\n";
+        else if (radix == 3) {
             source<<"mixed3 c0r = real"<<input<<"[i];\n";
             source<<"mixed3 c0i = imag"<<input<<"[i];\n";
             source<<"mixed3 c1r = real"<<input<<"[i+"<<(L*m)<<"];\n";
@@ -513,16 +507,8 @@ string CudaIntegrateRPMDStepKernel::createFFT(int size, const string& variable,
             source<<"imag"<<output<<"[i+(2*j+1)*"<<m<<"] = "<<multImag<<"(w[j*"<<size<<"/"<<(3*L)<<"], d1r+d2r, d1i+d2i);\n";
             source<<"real"<<output<<"[i+(2*j+2)*"<<m<<"] = "<<multReal<<"(w[j*"<<(2*size)<<"/"<<(3*L)<<"], d1r-d2r, d1i-d2i);\n";
             source<<"imag"<<output<<"[i+(2*j+2)*"<<m<<"] = "<<multImag<<"(w[j*"<<(2*size)<<"/"<<(3*L)<<"], d1r-d2r, d1i-d2i);\n";
-            source<<"}\n";
-            m = m*3;
-            unfactored /= 3;
         }
-        else if (unfactored%2 == 0) {
-            L = L/2;
-            source<<"// Pass "<<(stage+1)<<" (radix 2)\n";
-            source<<"if (indexInBlock < "<<(L*m)<<") {\n";
-            source<<"int i = indexInBlock;\n";
-            source<<"int j = i/"<<m<<";\n";
+        else if (radix == 2) {
             source<<"mixed3 c0r = real"<<input<<"[i];\n";
             source<<"mixed3 c0i = imag"<<input<<"[i];\n";
             source<<"mixed3 c1r = real"<<input<<"[i+"<<(L*m)<<"];\n";
@@ -531,12 +517,9 @@ string CudaIntegrateRPMDStepKernel::createFFT(int size, const string& variable,
             source<<"imag"<<output<<"[i+j*"<<m<<"] = c0i+c1i;\n";
             source<<"real"<<output<<"[i+(j+1)*"<<m<<"] = "<<multReal<<"(w[j*"<<size<<"/"<<(2*L)<<"], c0r-c1r, c0i-c1i);\n";
             source<<"imag"<<output<<"[i+(j+1)*"<<m<<"] = "<<multImag<<"(w[j*"<<size<<"/"<<(2*L)<<"], c0r-c1r, c0i-c1i);\n";
-            source<<"}\n";
-            m = m*2;
-            unfactored /= 2;
         }
-        else
-            throw OpenMMException("Illegal size for FFT: "+cu.intToString(size));
+        source<<"}\n";
+        m = m*radix;
         source<<"__syncthreads();\n";
         source<<"}\n";
         ++stage;

plugins/rpmd/platforms/opencl/src/OpenCLRpmdKernels.cpp

@@ -387,7 +387,6 @@ void OpenCLIntegrateRPMDStepKernel::copyToContext(int copy, ContextImpl& context
 
 string OpenCLIntegrateRPMDStepKernel::createFFT(int size, const string& variable, bool forward) {
     stringstream source;
-    int unfactored = size;
     int stage = 0;
     int L = size;
     int m = 1;
@@ -403,16 +402,27 @@ string OpenCLIntegrateRPMDStepKernel::createFFT(int size, const string& variable
 
     // Factor size, generating an appropriate block of code for each factor.
 
-    while (unfactored > 1) {
+    while (L > 1) {
         int input = stage%2;
         int output = 1-input;
+        int radix;
+        if (L%5 == 0)
+            radix = 5;
+        else if (L%4 == 0)
+            radix = 4;
+        else if (L%3 == 0)
+            radix = 3;
+        else if (L%2 == 0)
+            radix = 2;
+        else
+            throw OpenMMException("Illegal size for FFT: "+cl.intToString(size));
         source<<"{\n";
-        if (unfactored%5 == 0) {
-            L = L/5;
-            source<<"// Pass "<<(stage+1)<<" (radix 5)\n";
+        L = L/radix;
+        source<<"// Pass "<<(stage+1)<<" (radix "<<radix<<")\n";
         source<<"if (indexInBlock < "<<(L*m)<<") {\n";
         source<<"int i = indexInBlock;\n";
         source<<"int j = i/"<<m<<";\n";
+        if (radix == 5) {
             source<<"mixed4 c0r = real"<<input<<"[i];\n";
             source<<"mixed4 c0i = imag"<<input<<"[i];\n";
             source<<"mixed4 c1r = real"<<input<<"[i+"<<(L*m)<<"];\n";
@@ -456,16 +466,8 @@ string OpenCLIntegrateRPMDStepKernel::createFFT(int size, const string& variable
             source<<"imag"<<output<<"[i+(4*j+3)*"<<m<<"] = "<<multImag<<"(w[j*"<<(3*size)<<"/"<<(5*L)<<"], d8r-d10r, d8i-d10i);\n";
             source<<"real"<<output<<"[i+(4*j+4)*"<<m<<"] = "<<multReal<<"(w[j*"<<(4*size)<<"/"<<(5*L)<<"], d7r-d9r, d7i-d9i);\n";
             source<<"imag"<<output<<"[i+(4*j+4)*"<<m<<"] = "<<multImag<<"(w[j*"<<(4*size)<<"/"<<(5*L)<<"], d7r-d9r, d7i-d9i);\n";
-            source<<"}\n";
-            m = m*5;
-            unfactored /= 5;
         }
-        else if (unfactored%4 == 0) {
-            L = L/4;
-            source<<"// Pass "<<(stage+1)<<" (radix 4)\n";
-            source<<"if (indexInBlock < "<<(L*m)<<") {\n";
-            source<<"int i = indexInBlock;\n";
-            source<<"int j = i/"<<m<<";\n";
+        else if (radix == 4) {
             source<<"mixed4 c0r = real"<<input<<"[i];\n";
             source<<"mixed4 c0i = imag"<<input<<"[i];\n";
             source<<"mixed4 c1r = real"<<input<<"[i+"<<(L*m)<<"];\n";
@@ -490,16 +492,8 @@ string OpenCLIntegrateRPMDStepKernel::createFFT(int size, const string& variable
             source<<"imag"<<output<<"[i+(3*j+2)*"<<m<<"] = "<<multImag<<"(w[j*"<<(2*size)<<"/"<<(4*L)<<"], d0r-d2r, d0i-d2i);\n";
             source<<"real"<<output<<"[i+(3*j+3)*"<<m<<"] = "<<multReal<<"(w[j*"<<(3*size)<<"/"<<(4*L)<<"], d1r-d3r, d1i-d3i);\n";
             source<<"imag"<<output<<"[i+(3*j+3)*"<<m<<"] = "<<multImag<<"(w[j*"<<(3*size)<<"/"<<(4*L)<<"], d1r-d3r, d1i-d3i);\n";
-            source<<"}\n";
-            m = m*4;
-            unfactored /= 4;
         }
-        else if (unfactored%3 == 0) {
-            L = L/3;
-            source<<"// Pass "<<(stage+1)<<" (radix 3)\n";
-            source<<"if (indexInBlock < "<<(L*m)<<") {\n";
-            source<<"int i = indexInBlock;\n";
-            source<<"int j = i/"<<m<<";\n";
+        else if (radix == 3) {
             source<<"mixed4 c0r = real"<<input<<"[i];\n";
             source<<"mixed4 c0i = imag"<<input<<"[i];\n";
             source<<"mixed4 c1r = real"<<input<<"[i+"<<(L*m)<<"];\n";
@@ -518,16 +512,8 @@ string OpenCLIntegrateRPMDStepKernel::createFFT(int size, const string& variable
             source<<"imag"<<output<<"[i+(2*j+1)*"<<m<<"] = "<<multImag<<"(w[j*"<<size<<"/"<<(3*L)<<"], d1r+d2r, d1i+d2i);\n";
             source<<"real"<<output<<"[i+(2*j+2)*"<<m<<"] = "<<multReal<<"(w[j*"<<(2*size)<<"/"<<(3*L)<<"], d1r-d2r, d1i-d2i);\n";
             source<<"imag"<<output<<"[i+(2*j+2)*"<<m<<"] = "<<multImag<<"(w[j*"<<(2*size)<<"/"<<(3*L)<<"], d1r-d2r, d1i-d2i);\n";
-            source<<"}\n";
-            m = m*3;
-            unfactored /= 3;
         }
-        else if (unfactored%2 == 0) {
-            L = L/2;
-            source<<"// Pass "<<(stage+1)<<" (radix 2)\n";
-            source<<"if (indexInBlock < "<<(L*m)<<") {\n";
-            source<<"int i = indexInBlock;\n";
-            source<<"int j = i/"<<m<<";\n";
+        else if (radix == 2) {
             source<<"mixed4 c0r = real"<<input<<"[i];\n";
             source<<"mixed4 c0i = imag"<<input<<"[i];\n";
             source<<"mixed4 c1r = real"<<input<<"[i+"<<(L*m)<<"];\n";
@@ -536,12 +522,9 @@ string OpenCLIntegrateRPMDStepKernel::createFFT(int size, const string& variable
             source<<"imag"<<output<<"[i+j*"<<m<<"] = c0i+c1i;\n";
             source<<"real"<<output<<"[i+(j+1)*"<<m<<"] = "<<multReal<<"(w[j*"<<size<<"/"<<(2*L)<<"], c0r-c1r, c0i-c1i);\n";
             source<<"imag"<<output<<"[i+(j+1)*"<<m<<"] = "<<multImag<<"(w[j*"<<size<<"/"<<(2*L)<<"], c0r-c1r, c0i-c1i);\n";
-            source<<"}\n";
-            m = m*2;
-            unfactored /= 2;
         }
-        else
-            throw OpenMMException("Illegal size for FFT: "+cl.intToString(size));
+        source<<"}\n";
+        m = m*radix;
         source<<"barrier(CLK_LOCAL_MEM_FENCE);\n";
         source<<"}\n";
         ++stage;