Fixed bugs in CPU version of PME

platforms/opencl/src/OpenCLKernels.cpp

@@ -936,6 +936,8 @@ OpenCLCalcNonbondedForceKernel::~OpenCLCalcNonbondedForceKernel() {
         delete pmeBsplineModuliZ;
     if (pmeBsplineTheta != NULL)
         delete pmeBsplineTheta;
+    if (pmeBsplineDTheta != NULL)
+        delete pmeBsplineDTheta;
     if (pmeAtomRange != NULL)
         delete pmeAtomRange;
     if (pmeAtomGridIndex != NULL)
@@ -1059,6 +1061,9 @@ void OpenCLCalcNonbondedForceKernel::initialize(const System& system, const Nonb
         pmeBsplineModuliY = new OpenCLArray<cl_float>(cl, gridSizeY, "pmeBsplineModuliY");
         pmeBsplineModuliZ = new OpenCLArray<cl_float>(cl, gridSizeZ, "pmeBsplineModuliZ");
         pmeBsplineTheta = new OpenCLArray<mm_float4>(cl, PmeOrder*numParticles, "pmeBsplineTheta");
+        bool deviceIsCpu = (cl.getDevice().getInfo<CL_DEVICE_TYPE>() == CL_DEVICE_TYPE_CPU);
+        if (deviceIsCpu)
+            pmeBsplineDTheta = new OpenCLArray<mm_float4>(cl, PmeOrder*numParticles, "pmeBsplineTheta");
         pmeAtomRange = new OpenCLArray<cl_int>(cl, gridSizeX*gridSizeY*gridSizeZ+1, "pmeAtomRange");
         pmeAtomGridIndex = new OpenCLArray<mm_int2>(cl, numParticles, "pmeAtomGridIndex");
         sort = new OpenCLSort<mm_int2>(cl, cl.getNumAtoms(), "int2", "value.y");
@@ -1181,6 +1186,8 @@ double OpenCLCalcNonbondedForceKernel::execute(ContextImpl& context, bool includ
             pmeUpdateBsplinesKernel.setArg<cl::Buffer>(1, pmeBsplineTheta->getDeviceBuffer());
             pmeUpdateBsplinesKernel.setArg(2, OpenCLContext::ThreadBlockSize*PmeOrder*sizeof(mm_float4), NULL);
             pmeUpdateBsplinesKernel.setArg<cl::Buffer>(3, pmeAtomGridIndex->getDeviceBuffer());
+            if (deviceIsCpu)
+                pmeUpdateBsplinesKernel.setArg<cl::Buffer>(6, pmeBsplineDTheta->getDeviceBuffer());
             pmeAtomRangeKernel.setArg<cl::Buffer>(0, pmeAtomGridIndex->getDeviceBuffer());
             pmeAtomRangeKernel.setArg<cl::Buffer>(1, pmeAtomRange->getDeviceBuffer());
             pmeAtomRangeKernel.setArg<cl::Buffer>(2, cl.getPosq().getDeviceBuffer());
@@ -1198,6 +1205,11 @@ double OpenCLCalcNonbondedForceKernel::execute(ContextImpl& context, bool includ
             pmeInterpolateForceKernel.setArg<cl::Buffer>(0, cl.getPosq().getDeviceBuffer());
             pmeInterpolateForceKernel.setArg<cl::Buffer>(1, cl.getForceBuffers().getDeviceBuffer());
             pmeInterpolateForceKernel.setArg<cl::Buffer>(2, pmeGrid->getDeviceBuffer());
+            if (deviceIsCpu) {
+                pmeInterpolateForceKernel.setArg<cl::Buffer>(5, pmeBsplineTheta->getDeviceBuffer());
+                pmeInterpolateForceKernel.setArg<cl::Buffer>(6, pmeBsplineDTheta->getDeviceBuffer());
+            }
+            else
                 pmeInterpolateForceKernel.setArg(5, 2*interpolateForceThreads*PmeOrder*sizeof(mm_float4), NULL);
             if (cl.getSupports64BitGlobalAtomics()) {
                 pmeFinishSpreadChargeKernel = cl::Kernel(program, "finishSpreadCharge");

platforms/opencl/src/OpenCLKernels.h

@@ -460,8 +460,8 @@ class OpenCLCalcNonbondedForceKernel : public CalcNonbondedForceKernel {
 public:
     OpenCLCalcNonbondedForceKernel(std::string name, const Platform& platform, OpenCLContext& cl, System& system) : CalcNonbondedForceKernel(name, platform),
             hasInitializedKernel(false), cl(cl), sigmaEpsilon(NULL), exceptionParams(NULL), cosSinSums(NULL), pmeGrid(NULL),
-            pmeGrid2(NULL), pmeBsplineModuliX(NULL), pmeBsplineModuliY(NULL), pmeBsplineModuliZ(NULL), pmeBsplineTheta(NULL), pmeAtomRange(NULL),
-            pmeAtomGridIndex(NULL), sort(NULL), fft(NULL) {
+            pmeGrid2(NULL), pmeBsplineModuliX(NULL), pmeBsplineModuliY(NULL), pmeBsplineModuliZ(NULL), pmeBsplineTheta(NULL), pmeBsplineDTheta(NULL),
+            pmeAtomRange(NULL), pmeAtomGridIndex(NULL), sort(NULL), fft(NULL) {
     }
     ~OpenCLCalcNonbondedForceKernel();
     /**
@@ -492,6 +492,7 @@ private:
     OpenCLArray<cl_float>* pmeBsplineModuliY;
     OpenCLArray<cl_float>* pmeBsplineModuliZ;
     OpenCLArray<mm_float4>* pmeBsplineTheta;
+    OpenCLArray<mm_float4>* pmeBsplineDTheta;
     OpenCLArray<cl_int>* pmeAtomRange;
     OpenCLArray<mm_int2>* pmeAtomGridIndex;
     OpenCLSort<mm_int2>* sort;

platforms/opencl/src/kernels/pme_cpu.cl

-__kernel void updateBsplines(__global const float4* restrict posq, __global float4* restrict pmeBsplineTheta, __global float4* restrict pmeBsplineDTheta, __local float4* restrict bsplinesCache, __global int2* restrict pmeAtomGridIndex, float4 periodicBoxSize, float4 invPeriodicBoxSize) {
+__kernel void updateBsplines(__global const float4* restrict posq, __global float4* restrict pmeBsplineTheta, __local float4* restrict bsplinesCache, __global int2* restrict pmeAtomGridIndex, float4 periodicBoxSize, float4 invPeriodicBoxSize, __global float4* restrict pmeBsplineDTheta) {
     const float4 scale = 1.0f/(PME_ORDER-1);
     for (int i = get_global_id(0); i < NUM_ATOMS; i += get_global_size(0)) {
         __local float4* data = &bsplinesCache[get_local_id(0)*PME_ORDER];
@@ -112,7 +112,7 @@ __kernel void reciprocalConvolution(__global float2* restrict pmeGrid, __global
     energyBuffer[get_global_id(0)] += 0.5f*energy;
 }
 
-__kernel void gridInterpolateForce(__global const float4* restrict posq, __global float4* restrict forceBuffers, __global const float4* restrict pmeBsplineTheta, __global const float4* restrict pmeBsplineDTheta, __global const float2* restrict pmeGrid, float4 periodicBoxSize, float4 invPeriodicBoxSize) {
+__kernel void gridInterpolateForce(__global const float4* restrict posq, __global float4* restrict forceBuffers, __global const float2* restrict pmeGrid, float4 periodicBoxSize, float4 invPeriodicBoxSize, __global const float4* restrict pmeBsplineTheta, __global const float4* restrict pmeBsplineDTheta) {
     for (int atom = get_global_id(0); atom < NUM_ATOMS; atom += get_global_size(0)) {
         float4 force = 0.0f;
         float4 pos = posq[atom];