}
	d.crc = byteorder.BeUint32(b[8:])
	return nil
}

func update(crc uint32, tab *Table, p []byte, checkInitIEEE bool) uint32 {
	switch {
	case haveCastagnoli.Load() && tab == castagnoliTable:
		return updateCastagnoli(crc, p)
	case tab == IEEETable:
		if checkInitIEEE {
			ieeeOnce.Do(ieeeInit)
		}
		return updateIEEE(crc, p)
	default:
		return simpleUpdate(crc, tab, p)

package crc32

import "internal/cpu"

func castagnoliUpdate(crc uint32, p []byte) uint32
func ieeeUpdate(crc uint32, p []byte) uint32

func archAvailableCastagnoli() bool {
	return cpu.ARM64.HasCRC32
}

func archInitCastagnoli() {
	if !cpu.ARM64.HasCRC32 {
		panic("arch-specific crc32 instruction for Castagnoli not available")
	}
}

func archUpdateCastagnoli(crc uint32, p []byte) uint32 {
	if !cpu.ARM64.HasCRC32 {

// license that can be found in the LICENSE file.

#include "textflag.h"

// castagnoliUpdate updates the non-inverted crc with the given data.

// func castagnoliUpdate(crc uint32, p []byte) uint32
TEXT ·castagnoliUpdate(SB),NOSPLIT,$0-36
	MOVWU	crc+0(FP), R9  // CRC value
	MOVD	p+8(FP), R13  // data pointer
	MOVD	p_len+16(FP), R11  // len(p)

update:
	CMP	$16, R11
	BLT	less_than_16

  }

  private static int referenceCrc(byte[] bytes) {
    int crc = ~0;
    for (byte b : bytes) {
      crc = (crc >>> 8) ^ Crc32cHashFunction.Crc32cHasher.BYTE_TABLE[(crc ^ b) & 0xFF];
    }
    return ~crc;
  }

  /**
   * Verifies that the crc of an array of byte data matches the expected value.
   *
   * @param expectedCrc the expected crc value.
   * @param data the data to run the checksum on.
   */

	// Seed (random)
	crc := uint64(0xc2b40bbac11a7295)
	// Xor each value to make order independent
	for k, v := range m {
		// Separate key and value with an individual xor with a random number.
		// Add values of each, so they cannot be trivially collided.
		crc ^= (xxh3.HashString(k) ^ 0x4ee3bbaf7ab2506b) + (xxh3.HashString(v) ^ 0x8da4c8da66194257)
	}
	return crc
}

// license that can be found in the LICENSE file.

#include "textflag.h"

// castagnoliSSE42 updates the (non-inverted) crc with the given buffer.
//
// func castagnoliSSE42(crc uint32, p []byte) uint32
TEXT ·castagnoliSSE42(SB),NOSPLIT,$0
	MOVL crc+0(FP), AX  // CRC value
	MOVQ p+8(FP), SI  // data pointer
	MOVQ p_len+16(FP), CX  // len(p)

	// If there are fewer than 8 bytes to process, skip alignment.

	for i := range crctab {
		crc := uint32(i) << 24
		for j := 0; j < 8; j++ {
			if crc&0x80000000 != 0 {
				crc = (crc << 1) ^ poly
			} else {
				crc <<= 1
			}
		}
		crctab[i] = crc
	}
}

// updateCRC updates the crc value to incorporate the data in b.
// The initial value is 0.
func updateCRC(val uint32, b []byte) uint32 {
	crc := ^val
	for _, v := range b {

func archInitIEEE()                              { panic("not available") }
func archUpdateIEEE(crc uint32, p []byte) uint32 { panic("not available") }

func archAvailableCastagnoli() bool                    { return false }
func archInitCastagnoli()                              { panic("not available") }

    /*
     * The striding algorithm works roughly as follows: it is universally the case that
     * CRC(x ^ y) == CRC(x) ^ CRC(y).  The approach we take is to break the message as follows,
     * with each letter representing a 4-byte word: ABCDABCDABCDABCD... and to calculate
     * CRC(A000A000A000...), CRC(0B000B000B...), CRC(00C000C000C...), CRC(000D000D000D...)
     * and then to XOR them together.  The STRIDE_TABLE enables us to hash an int followed by 12

	name = Go Gopher
	email = ******@****.***
[init]
	defaultBranch = main
[core]
	eol = lf
[gui]
	encoding = utf-8
`[1:]

// hgrc contains a ~/.hgrc file that attempts to provide
// deterministic, platform-agnostic behavior for the 'hg' command.
var hgrc = `
[ui]
username=Go Gopher <******@****.***>
[phases]
new-commit=public
[extensions]
convert=
`[1:]