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NLnetLabs
simdzone
C2023–2024
NLnetLabs / simdzone

simdzone

Fast and standards compliant DNS zone parser

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3Distinct people
3Mentions
0Explicit recommenders
140GitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

Fast and standards compliant DNS zone parser

GitHub

Where it is used

No documented product use has been verified yet.

What people are saying

No recommendation phrase was found in the indexed comments.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

No other repository is repeatedly linked in the same discussions.

This week on Hacker News

Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 1:49:46 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by month3 dated mentions

Observed mentions: 2023-05-03 21:38:51 UTC to 2024-12-10 16:06:46 UTC.

012023-05-01 00:00:00 UTC to 2023-06-01 00:00:00 UTC (exclusive): 1 mentions; 1 submissions, 0 commentsMay 20232023-06-01 00:00:00 UTC to 2023-07-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-07-01 00:00:00 UTC to 2023-08-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-08-01 00:00:00 UTC to 2023-09-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2023-09-01 00:00:00 UTC to 2023-10-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-10-01 00:00:00 UTC to 2023-11-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-11-01 00:00:00 UTC to 2023-12-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-12-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-01-01 00:00:00 UTC to 2024-02-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-02-01 00:00:00 UTC to 2024-03-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 commentsFeb 20242024-03-01 00:00:00 UTC to 2024-04-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-04-01 00:00:00 UTC to 2024-05-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-05-01 00:00:00 UTC to 2024-06-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-06-01 00:00:00 UTC to 2024-07-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-07-01 00:00:00 UTC to 2024-08-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-08-01 00:00:00 UTC to 2024-09-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-09-01 00:00:00 UTC to 2024-10-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-10-01 00:00:00 UTC to 2024-11-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-11-01 00:00:00 UTC to 2024-12-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-12-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 1 mentions; 1 submissions, 0 commentsDec 2024

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
May 20232023-05-01 00:00:00 UTC2023-06-01 00:00:00 UTC110
Jun 20232023-06-01 00:00:00 UTC2023-07-01 00:00:00 UTC000
Jul 20232023-07-01 00:00:00 UTC2023-08-01 00:00:00 UTC000
Aug 20232023-08-01 00:00:00 UTC2023-09-01 00:00:00 UTC101
Sep 20232023-09-01 00:00:00 UTC2023-10-01 00:00:00 UTC000
Oct 20232023-10-01 00:00:00 UTC2023-11-01 00:00:00 UTC000
Nov 20232023-11-01 00:00:00 UTC2023-12-01 00:00:00 UTC000
Dec 20232023-12-01 00:00:00 UTC2024-01-01 00:00:00 UTC000
Jan 20242024-01-01 00:00:00 UTC2024-02-01 00:00:00 UTC000
Feb 20242024-02-01 00:00:00 UTC2024-03-01 00:00:00 UTC000
Mar 20242024-03-01 00:00:00 UTC2024-04-01 00:00:00 UTC000
Apr 20242024-04-01 00:00:00 UTC2024-05-01 00:00:00 UTC000
May 20242024-05-01 00:00:00 UTC2024-06-01 00:00:00 UTC000
Jun 20242024-06-01 00:00:00 UTC2024-07-01 00:00:00 UTC000
Jul 20242024-07-01 00:00:00 UTC2024-08-01 00:00:00 UTC000
Aug 20242024-08-01 00:00:00 UTC2024-09-01 00:00:00 UTC000
Sep 20242024-09-01 00:00:00 UTC2024-10-01 00:00:00 UTC000
Oct 20242024-10-01 00:00:00 UTC2024-11-01 00:00:00 UTC000
Nov 20242024-11-01 00:00:00 UTC2024-12-01 00:00:00 UTC000
Dec 20242024-12-01 00:00:00 UTC2025-01-01 00:00:00 UTC110

What Hacker News says

3 sources
1letterunixname·Aug 5, 2023
Hexadecimal is a number system that wasn't designed for any particular computation or conversion with anything but to fit efficiently in nibbles and bytes. You maybe conflating encodings like ASCII and EBCDIC as "designed" for mechanical conversion. Firstly, how are you going to select whichever of the following is between 0..9 branchlessly and cheaply? x0 = c - '0' result = (x0 < 10) ? x0 : (c - 'A' + 10) Answer: You're not. Instead, DELTA_CHECK and DELTA_REBASE aren't specified M128I V // 16 hex chars as ASCII/Latin-1 bytes M128I VM1, HASH_KEY, CHECK, T3, T5 UINT M // 2. Subtract 1 from all character values FOR I := 0 TO 15 DO VM1[I; I8] = V[I; I8] - 1 DONE // 3. Using a 4-bit shift and a mask, select the most significant 4 bits of each byte value. FOR I := 0 TO 3 DO HASH
Read the rest
_KEY[I; U32] = (VM1[I; U32] >> 4) AND 0x0F0F0F0F DONE // 4. Do a vectorized table lookup using the most significant 4 bits, and add the result to the value. This inexpensive computation can detect any non-hexadecimal character: any such character would map to a byte value with the most significant bit set. We later branch out based on a movemask which detects these bytes. FOR I := 0 TO 15 DO IF HASH_KEY[I; I8] & 0x80 != 0 THEN CHECK[I; I8] = VM1[I; I8] ELSE CHECK[I; I8] = VM1[I; I8] + DELTA_CHECK[(HASH_KEY[I; I8] & 0x0F); I8] ENDIF DONE // 5. We do a similar computation, a vectorized table lookup using the most significant 4 bits, and add the result to the value, to map the character to a 4-bit value (between 0 and 16 [15 sic]). FOR I := 0 TO 15 DO IF HASH_KEY[I; I8] & 0x80 != 0 THEN V[I; I8] = VM1[I; I8] ELSE V[I; I8] = VM1[I; I8] + DELTA_REBASE[(HASH_KEY[I; I8] & 0x0F); I8] ENDIF DONE // [check MSB of each byte in CHECK for error] FOR I := 0 TO 15 DO IF (CHECK[I; U8] >> 7) != 0 THEN ERROR ENDIF DONE // 6. We use a multiply-add and a pack instruction to pack the 4-bit values, going from 16 bytes to 8 bytes. // b = 0x0110_0110_0110_0110_0110_0110_0110_0110 FOR I := 0 TO 7 DO // dst[i+15:i] := a[i+15:i+8]*b[i+15:i+8] + a[i+7:i]*b[i+7:i] // dst[i+15:i] := a[i+15:i+8]*1 + a[i+7:i]*16 T3[I; I16] = MIN(V[2*I+1; U8] + (V[2*I; U8] << 4), 0xffff) DONE FOR I := 0 TO 7 DO T5[I; U8] = MIN(T3[2*I; I16], 0xff) T5[I+7; U8] = MIN(T3[2*I; I16], 0xff) // duplicate, thrown away in the final result DONE // 7. We write the 8 bytes to the output. [The later code ignores the top 8 bytes of t5] Related: Base32 and base16 vectorized decoding in simdzone https://github.com/NLnetLabs/simdzone/issues/28 https://github.com/NLnetLabs/simdzone/issues/26
In Decoding base16 sequences quickly

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