| /* { dg-do compile } */ |
| /* { dg-require-effective-target popcount } */ |
| /* { dg-require-effective-target int32plus } */ |
| /* { dg-options "-O2 -fdump-tree-optimized" } */ |
| |
| const unsigned m1 = 0x55555555UL; |
| const unsigned m2 = 0x33333333UL; |
| const unsigned m4 = 0x0F0F0F0FUL; |
| const unsigned h01 = 0x01010101UL; |
| const int shift = 24; |
| |
| int popcount64c(unsigned x) |
| { |
| x -= (x >> 1) & m1; |
| x = (x & m2) + ((x >> 2) & m2); |
| x = (x + (x >> 4)) & m4; |
| return (x * h01) >> shift; |
| } |
| |
| /* { dg-final { scan-tree-dump-times "\.POPCOUNT" 1 "optimized" } } */ |
| |
| |
