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36 #ifndef GMX_MDLIB_NBNXN_UTIL_H
37 #define GMX_MDLIB_NBNXN_UTIL_H
41 #include "gromacs/mdlib/nb_verlet.h"
42 #include "gromacs/mdlib/nbnxn_consts.h"
43 #include "gromacs/mdlib/nbnxn_pairlist.h"
44 #include "gromacs/simd/simd.h"
45 #include "gromacs/utility/fatalerror.h"
48 /* Returns the base-2 log of n.
49 * Generates a fatal error when n is not an integer power of 2.
51 static inline int get_2log(int n)
56 while ((1 << log2) < n)
62 gmx_fatal(FARGS, "nbnxn na_c (%d) is not a power of 2", n);
68 /* Returns the nbnxn i-cluster size in atoms for the nbnxn kernel type */
69 static inline int nbnxn_kernel_to_cluster_i_size(int nb_kernel_type)
71 switch (nb_kernel_type)
73 case nbnxnk4x4_PlainC:
74 case nbnxnk4xN_SIMD_4xN:
75 case nbnxnk4xN_SIMD_2xNN:
76 return c_nbnxnCpuIClusterSize;
78 case nbnxnk8x8x8_PlainC:
79 /* The cluster size for super/sub lists is only set here.
80 * Any value should work for the pair-search and atomdata code.
81 * The kernels, of course, might require a particular value.
83 return c_nbnxnGpuClusterSize;
85 gmx_incons("unknown kernel type");
91 /* Returns the nbnxn i-cluster size in atoms for the nbnxn kernel type */
92 static inline int nbnxn_kernel_to_cluster_j_size(int nb_kernel_type)
94 int nbnxn_simd_width = 0;
98 nbnxn_simd_width = GMX_SIMD_REAL_WIDTH;
101 switch (nb_kernel_type)
103 case nbnxnk4x4_PlainC:
104 cj_size = c_nbnxnCpuIClusterSize;
106 case nbnxnk4xN_SIMD_4xN:
107 cj_size = nbnxn_simd_width;
109 case nbnxnk4xN_SIMD_2xNN:
110 cj_size = nbnxn_simd_width/2;
112 case nbnxnk8x8x8_GPU:
113 case nbnxnk8x8x8_PlainC:
114 cj_size = nbnxn_kernel_to_cluster_i_size(nb_kernel_type);
117 gmx_incons("unknown kernel type");