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Comparing libecb/ecb.h (file contents):
Revision 1.210 by root, Fri Mar 25 15:28:08 2022 UTC vs.
Revision 1.212 by root, Fri Mar 25 15:31:22 2022 UTC

… …
356#define ECB_STRINGIFY_(a) # a 356#define ECB_STRINGIFY_(a) # a
357#define ECB_STRINGIFY(a) ECB_STRINGIFY_(a) 357#define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
358#define ECB_STRINGIFY_EXPR(expr) ((expr), ECB_STRINGIFY_ (expr)) 358#define ECB_STRINGIFY_EXPR(expr) ((expr), ECB_STRINGIFY_ (expr))
359 359
360/* This marks larger functions that do not neccessarily need to be inlined */ 360/* This marks larger functions that do not neccessarily need to be inlined */
361/* The idea is to possibly compile the header twice, */
362/* once exposing only the declarations, another time to define external functions */
361/* TODO: popssibly static would be best for these at the moment? */ 363/* TODO: possibly static would be best for these at the moment? */
362#define ecb_function_ ecb_inline 364#define ecb_function_ ecb_inline
363 365
364#if ECB_GCC_VERSION(3,1) || ECB_CLANG_VERSION(2,8) 366#if ECB_GCC_VERSION(3,1) || ECB_CLANG_VERSION(2,8)
365 #define ecb_attribute(attrlist) __attribute__ (attrlist) 367 #define ecb_attribute(attrlist) __attribute__ (attrlist)
366#else 368#else
… …
1033/*****************************************************************************/ 1035/*****************************************************************************/
1034/* 2d hilbert curves */ 1036/* 2d hilbert curves */
1035 1037
1036/* algorithm from the book Hacker's Delight, modified to not */ 1038/* algorithm from the book Hacker's Delight, modified to not */
1037/* run into undefined behaviour for n==16 */ 1039/* run into undefined behaviour for n==16 */
1038static uint32_t 1040static uint32_t ecb_hilbert2d_index_to_coord32 (int n, uint32_t s);
1039ecb_hilbert2d_index_to_coord32 (int n, uint32_t s) 1041static uint32_t ecb_hilbert2d_index_to_coord32 (int n, uint32_t s)
1040{ 1042{
1041 uint32_t comp, swap, cs, t, sr; 1043 uint32_t comp, swap, cs, t, sr;
1042 1044
1043 /* pad s on the left (unused) bits with 01 (no change groups) */ 1045 /* pad s on the left (unused) bits with 01 (no change groups) */
1044 s |= 0x55555555U << n << n; 1046 s |= 0x55555555U << n << n;
… …
1078 /* now s contains two 16-bit coordinates */ 1080 /* now s contains two 16-bit coordinates */
1079 return s; 1081 return s;
1080} 1082}
1081 1083
1082/* 64 bit, a straightforward extension to the 32 bit case */ 1084/* 64 bit, a straightforward extension to the 32 bit case */
1083static uint64_t 1085static uint64_t ecb_hilbert2d_index_to_coord64 (int n, uint64_t s);
1084ecb_hilbert2d_index_to_coord64 (int n, uint64_t s) 1086static uint64_t ecb_hilbert2d_index_to_coord64 (int n, uint64_t s)
1085{ 1087{
1086 uint64_t comp, swap, cs, t, sr; 1088 uint64_t comp, swap, cs, t, sr;
1087 1089
1088 /* pad s on the left (unused) bits with 01 (no change groups) */ 1090 /* pad s on the left (unused) bits with 01 (no change groups) */
1089 s |= 0x5555555555555555U << n << n; 1091 s |= 0x5555555555555555U << n << n;
… …
1127} 1129}
1128 1130
1129/* algorithm from the book Hacker's Delight, but a similar algorithm*/ 1131/* algorithm from the book Hacker's Delight, but a similar algorithm*/
1130/* is given in https://doi.org/10.1002/spe.4380160103 */ 1132/* is given in https://doi.org/10.1002/spe.4380160103 */
1131/* this has been slightly improved over the original version */ 1133/* this has been slightly improved over the original version */
1132ecb_function_ uint32_t 1134ecb_function_ uint32_t ecb_hilbert2d_coord_to_index32 (int n, uint32_t xy);
1133ecb_hilbert2d_coord_to_index32 (int n, uint32_t xy) 1135ecb_function_ uint32_t ecb_hilbert2d_coord_to_index32 (int n, uint32_t xy)
1134{ 1136{
1135 uint32_t row; 1137 uint32_t row;
1136 uint32_t state = 0; 1138 uint32_t state = 0;
1137 uint32_t s = 0; 1139 uint32_t s = 0;
1138 1140
… …
1152 1154
1153 return s; 1155 return s;
1154} 1156}
1155 1157
1156/* 64 bit, essentially the same as 32 bit */ 1158/* 64 bit, essentially the same as 32 bit */
1157ecb_function_ uint64_t 1159ecb_function_ uint64_t ecb_hilbert2d_coord_to_index64 (int n, uint64_t xy);
1158ecb_hilbert2d_coord_to_index64 (int n, uint64_t xy) 1160ecb_function_ uint64_t ecb_hilbert2d_coord_to_index64 (int n, uint64_t xy)
1159{ 1161{
1160 uint32_t row; 1162 uint32_t row;
1161 uint32_t state = 0; 1163 uint32_t state = 0;
1162 uint64_t s = 0; 1164 uint64_t s = 0;
1163 1165

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