paweld/fpc
1
0
Fork 0
mirror of https://gitlab.com/freepascal.org/fpc/source.git synced 2025-04-05 10:58:06 +02:00
Code Issues Packages Projects Releases Wiki Activity

* make UpdateFnv64 closer to the original algorithm as proposed by Gareth

Browse Source
This commit is contained in:
florian 2024-09-15 21:48:32 +02:00
parent beee98e246
commit 0e0c4bd621
2 changed files with 3 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
compiler/fpchash.pas
View File

@ -116,11 +116,6 @@ function InitFnv64: uint64;
function UpdateFnv64(const InitFnv: uint64; const InBuf; InLen: Integer): uint64; function UpdateFnv64(const InitFnv: uint64; const InBuf; InLen: Integer): uint64;
const const
M = uint64(1099511628211); M = uint64(1099511628211);
{ Compiler yells at you for overflows in constants, even with disabled range checks,
so there are precalculated values for unrolled loop: M^2, M^3, M^4. }
Mp2 = uint64(956575116354345);
Mp3 = uint64(624165263380053675);
Mp4 = uint64(11527715348014283921);
var var
pp: pByte; pp: pByte;
begin begin
@ -128,13 +123,13 @@ begin
pp := @InBuf; pp := @InBuf;
while InLen >= 4 do while InLen >= 4 do
begin begin
result := (result + pp[0]) * Mp4 + pp[1] * Mp3 + pp[2] * Mp2 + pp[3] * M; result := ((((result xor pp[0]) * M xor pp[1]) * M xor pp[2]) * M xor pp[3]) * M;
pp := pp + 4; pp := pp + 4;
InLen := InLen - 4; InLen := InLen - 4;
end; end;
while InLen > 0 do while InLen > 0 do
begin begin
result := (result + pp^) * M; result := (result xor pp^) * M;
pp := pp + 1; pp := pp + 1;
InLen := InLen - 1; InLen := InLen - 1;
end; end;

2
compiler/ppu.pas
View File

@ -48,7 +48,7 @@ const
CurrentPPUVersion = 208; CurrentPPUVersion = 208;
{ for any other changes to the ppu format, increase this version number { for any other changes to the ppu format, increase this version number
(it's a cardinal) } (it's a cardinal) }
CurrentPPULongVersion = 25; CurrentPPULongVersion = 26;
{ unit flags } { unit flags }
uf_big_endian = $000004; uf_big_endian = $000004;