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author | Björn-Egil Dahlberg <[email protected]> | 2015-01-21 16:08:17 +0100 |
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committer | Björn-Egil Dahlberg <[email protected]> | 2015-03-12 19:15:25 +0100 |
commit | 0d10df770cfd1407bb79c31da34108dda1b868a5 (patch) | |
tree | fc928d9ef3e768a98e691734c531dc9b3f1bf68c /erts/emulator/beam/erl_hashmap.h | |
parent | 3cdd2d25859275fd0bc2111c52a8bbd2505ff048 (diff) | |
download | otp-0d10df770cfd1407bb79c31da34108dda1b868a5.tar.gz otp-0d10df770cfd1407bb79c31da34108dda1b868a5.tar.bz2 otp-0d10df770cfd1407bb79c31da34108dda1b868a5.zip |
erts: Add fallback for builtin clz
* __builtin_clz may not exist
* fix bitcount fallback
Diffstat (limited to 'erts/emulator/beam/erl_hashmap.h')
-rw-r--r-- | erts/emulator/beam/erl_hashmap.h | 17 |
1 files changed, 4 insertions, 13 deletions
diff --git a/erts/emulator/beam/erl_hashmap.h b/erts/emulator/beam/erl_hashmap.h index 8ba249b053..1964787218 100644 --- a/erts/emulator/beam/erl_hashmap.h +++ b/erts/emulator/beam/erl_hashmap.h @@ -40,21 +40,12 @@ int hashmap_key_hash_cmp(Eterm* ap, Eterm* bp); /* HASH */ - #if defined(__GNUC__) -#define hashmap_bitcount(x) (Uint32) __builtin_popcount((unsigned int) (x)) +#define hashmap_clz(x) ((Uint32) __builtin_clz((unsigned int)(x))) +#define hashmap_bitcount(x) ((Uint32) __builtin_popcount((unsigned int) (x))) #else -const Uint32 SK5 = 0x55555555, SK3 = 0x33333333; -const Uint32 SKF0 = 0xF0F0F0F, SKFF = 0xFF00FF; - -/* CTPOP emulation */ -Uint32 hashmap_bitcount(Uint32 map) { - map -= (( map >> 1 ) & SK5 ); - map = ( map & SK3 ) + (( map >> 2 ) & SK3 ); - map = ( map & SKF0 ) + (( map >> 4 ) & SKF0); - map += map >> 8; - return ( map + ( map >> 16)) & 0x3F; -} +Uint32 hashmap_clz(Uint32 x); +Uint32 hashmap_bitcount(Uint32 x); #endif /* hamt nodes v2.0 |