diff options
| -rw-r--r-- | core/hash/hash.odin | 43 |
1 files changed, 38 insertions, 5 deletions
diff --git a/core/hash/hash.odin b/core/hash/hash.odin index 6740629be..36dda9333 100644 --- a/core/hash/hash.odin +++ b/core/hash/hash.odin @@ -1,16 +1,49 @@ package hash import "core:mem" +import "intrinsics" @(optimization_mode="speed") -adler32 :: proc(data: []byte, seed := u32(1)) -> u32 { +adler32 :: proc(data: []byte, seed := u32(1)) -> u32 #no_bounds_check { + ADLER_CONST :: 65521; - a, b: u32 = seed & 0xFFFF, seed >> 16; - #no_bounds_check for x in data { - a = (a + u32(x)) % ADLER_CONST; + + buffer := raw_data(data); + a, b: u64 = u64(seed) & 0xFFFF, u64(seed) >> 16; + buf := data[:]; + + for len(buf) != 0 && uintptr(buffer) & 7 != 0 { + a = (a + u64(buf[0])); + b = (b + a); + buffer = intrinsics.ptr_offset(buffer, 1); + buf = buf[1:]; + } + + for len(buf) > 7 { + count := min(len(buf), 5552); + for count > 7 { + a += u64(buf[0]); b += a; + a += u64(buf[1]); b += a; + a += u64(buf[2]); b += a; + a += u64(buf[3]); b += a; + a += u64(buf[4]); b += a; + a += u64(buf[5]); b += a; + a += u64(buf[6]); b += a; + a += u64(buf[7]); b += a; + + buf = buf[8:]; + count -= 8; + } + a %= ADLER_CONST; + b %= ADLER_CONST; + } + + for len(buf) != 0 { + a = (a + u64(buf[0])) % ADLER_CONST; b = (b + a) % ADLER_CONST; + buf = buf[1:]; } - return (b << 16) | a; + return (u32(b) << 16) | u32(a); } @(optimization_mode="speed") |