hash: 64 bit variants.

ccan/hash/_info

@@ -1,4 +1,5 @@
 #include <string.h>
+#include <stdio.h>
 
 /**
  * hash - routines for hashing bytes
@@ -22,6 +23,7 @@ int main(int argc, char *argv[])
 		return 1;
 
 	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/build_assert\n");
 		return 0;
 	}
 

ccan/hash/hash.c

@@ -208,63 +208,16 @@ uint32_t        initval)         /* the previous hash, or an arbitrary value */
   return c;
 }
 
-
-#if 0
-/*
---------------------------------------------------------------------
-hash_word2() -- same as hash_word(), but take two seeds and return two
-32-bit values.  pc and pb must both be nonnull, and *pc and *pb must
-both be initialized with seeds.  If you pass in (*pb)==0, the output 
-(*pc) will be the same as the return value from hash_word().
---------------------------------------------------------------------
-*/
-void hash_word2 (
-const uint32_t *k,                   /* the key, an array of uint32_t values */
-size_t          length,               /* the length of the key, in uint32_ts */
-uint32_t       *pc,                      /* IN: seed OUT: primary hash value */
-uint32_t       *pb)               /* IN: more seed OUT: secondary hash value */
-{
-  uint32_t a,b,c;
-
-  /* Set up the internal state */
-  a = b = c = 0xdeadbeef + ((uint32_t)(length<<2)) + *pc;
-  c += *pb;
-
-  /*------------------------------------------------- handle most of the key */
-  while (length > 3)
-  {
-    a += k[0];
-    b += k[1];
-    c += k[2];
-    mix(a,b,c);
-    length -= 3;
-    k += 3;
-  }
-
-  /*------------------------------------------- handle the last 3 uint32_t's */
-  switch(length)                     /* all the case statements fall through */
-  { 
-  case 3 : c+=k[2];
-  case 2 : b+=k[1];
-  case 1 : a+=k[0];
-    final(a,b,c);
-  case 0:     /* case 0: nothing left to add */
-    break;
-  }
-  /*------------------------------------------------------ report the result */
-  *pc=c; *pb=b;
-}
-#endif
-
 /*
 -------------------------------------------------------------------------------
 hashlittle() -- hash a variable-length key into a 32-bit value
   k       : the key (the unaligned variable-length array of bytes)
   length  : the length of the key, counting by bytes
-  initval : can be any 4-byte value
+  val2    : IN: can be any 4-byte value OUT: second 32 bit hash.
 Returns a 32-bit value.  Every bit of the key affects every bit of
 the return value.  Two keys differing by one or two bits will have
-totally different hash values.
+totally different hash values.  Note that the return value is better
+mixed than val2, so use that first.
 
 The best hash table sizes are powers of 2.  There is no need to do
 mod a prime (mod is sooo slow!).  If you need less than 32 bits,
@@ -283,13 +236,13 @@ acceptable.  Do NOT use for cryptographic purposes.
 -------------------------------------------------------------------------------
 */
 
-static uint32_t hashlittle( const void *key, size_t length, uint32_t initval)
+static uint32_t hashlittle( const void *key, size_t length, uint32_t *val2 )
 {
   uint32_t a,b,c;                                          /* internal state */
   union { const void *ptr; size_t i; } u;     /* needed for Mac Powerbook G4 */
 
   /* Set up the internal state */
-  a = b = c = 0xdeadbeef + ((uint32_t)length) + initval;
+  a = b = c = 0xdeadbeef + ((uint32_t)length) + *val2;
 
   u.ptr = key;
   if (HASH_LITTLE_ENDIAN && ((u.i & 0x3) == 0)) {
@@ -451,209 +404,23 @@ static uint32_t hashlittle( const void *key, size_t length, uint32_t initval)
   }
 
   final(a,b,c);
+  *val2 = b;
   return c;
 }
 
-#if 0
-/*
- * hashlittle2: return 2 32-bit hash values
- *
- * This is identical to hashlittle(), except it returns two 32-bit hash
- * values instead of just one.  This is good enough for hash table
- * lookup with 2^^64 buckets, or if you want a second hash if you're not
- * happy with the first, or if you want a probably-unique 64-bit ID for
- * the key.  *pc is better mixed than *pb, so use *pc first.  If you want
- * a 64-bit value do something like "*pc + (((uint64_t)*pb)<<32)".
- */
-void hashlittle2( 
-  const void *key,       /* the key to hash */
-  size_t      length,    /* length of the key */
-  uint32_t   *pc,        /* IN: primary initval, OUT: primary hash */
-  uint32_t   *pb)        /* IN: secondary initval, OUT: secondary hash */
-{
-  uint32_t a,b,c;                                          /* internal state */
-  union { const void *ptr; size_t i; } u;     /* needed for Mac Powerbook G4 */
-
-  /* Set up the internal state */
-  a = b = c = 0xdeadbeef + ((uint32_t)length) + *pc;
-  c += *pb;
-
-  u.ptr = key;
-  if (HASH_LITTLE_ENDIAN && ((u.i & 0x3) == 0)) {
-    const uint32_t *k = (const uint32_t *)key;         /* read 32-bit chunks */
-    const uint8_t  *k8;
-
-    /*------ all but last block: aligned reads and affect 32 bits of (a,b,c) */
-    while (length > 12)
-    {
-      a += k[0];
-      b += k[1];
-      c += k[2];
-      mix(a,b,c);
-      length -= 12;
-      k += 3;
-    }
-
-    /*----------------------------- handle the last (probably partial) block */
-    /* 
-     * "k[2]&0xffffff" actually reads beyond the end of the string, but
-     * then masks off the part it's not allowed to read.  Because the
-     * string is aligned, the masked-off tail is in the same word as the
-     * rest of the string.  Every machine with memory protection I've seen
-     * does it on word boundaries, so is OK with this.  But VALGRIND will
-     * still catch it and complain.  The masking trick does make the hash
-     * noticably faster for short strings (like English words).
-     */
-#ifndef VALGRIND
-
-    switch(length)
-    {
-    case 12: c+=k[2]; b+=k[1]; a+=k[0]; break;
-    case 11: c+=k[2]&0xffffff; b+=k[1]; a+=k[0]; break;
-    case 10: c+=k[2]&0xffff; b+=k[1]; a+=k[0]; break;
-    case 9 : c+=k[2]&0xff; b+=k[1]; a+=k[0]; break;
-    case 8 : b+=k[1]; a+=k[0]; break;
-    case 7 : b+=k[1]&0xffffff; a+=k[0]; break;
-    case 6 : b+=k[1]&0xffff; a+=k[0]; break;
-    case 5 : b+=k[1]&0xff; a+=k[0]; break;
-    case 4 : a+=k[0]; break;
-    case 3 : a+=k[0]&0xffffff; break;
-    case 2 : a+=k[0]&0xffff; break;
-    case 1 : a+=k[0]&0xff; break;
-    case 0 : *pc=c; *pb=b; return;  /* zero length strings require no mixing */
-    }
-
-#else /* make valgrind happy */
-
-    k8 = (const uint8_t *)k;
-    switch(length)
-    {
-    case 12: c+=k[2]; b+=k[1]; a+=k[0]; break;
-    case 11: c+=((uint32_t)k8[10])<<16;  /* fall through */
-    case 10: c+=((uint32_t)k8[9])<<8;    /* fall through */
-    case 9 : c+=k8[8];                   /* fall through */
-    case 8 : b+=k[1]; a+=k[0]; break;
-    case 7 : b+=((uint32_t)k8[6])<<16;   /* fall through */
-    case 6 : b+=((uint32_t)k8[5])<<8;    /* fall through */
-    case 5 : b+=k8[4];                   /* fall through */
-    case 4 : a+=k[0]; break;
-    case 3 : a+=((uint32_t)k8[2])<<16;   /* fall through */
-    case 2 : a+=((uint32_t)k8[1])<<8;    /* fall through */
-    case 1 : a+=k8[0]; break;
-    case 0 : *pc=c; *pb=b; return;  /* zero length strings require no mixing */
-    }
-
-#endif /* !valgrind */
-
-  } else if (HASH_LITTLE_ENDIAN && ((u.i & 0x1) == 0)) {
-    const uint16_t *k = (const uint16_t *)key;         /* read 16-bit chunks */
-    const uint8_t  *k8;
-
-    /*--------------- all but last block: aligned reads and different mixing */
-    while (length > 12)
-    {
-      a += k[0] + (((uint32_t)k[1])<<16);
-      b += k[2] + (((uint32_t)k[3])<<16);
-      c += k[4] + (((uint32_t)k[5])<<16);
-      mix(a,b,c);
-      length -= 12;
-      k += 6;
-    }
-
-    /*----------------------------- handle the last (probably partial) block */
-    k8 = (const uint8_t *)k;
-    switch(length)
-    {
-    case 12: c+=k[4]+(((uint32_t)k[5])<<16);
-             b+=k[2]+(((uint32_t)k[3])<<16);
-             a+=k[0]+(((uint32_t)k[1])<<16);
-             break;
-    case 11: c+=((uint32_t)k8[10])<<16;     /* fall through */
-    case 10: c+=k[4];
-             b+=k[2]+(((uint32_t)k[3])<<16);
-             a+=k[0]+(((uint32_t)k[1])<<16);
-             break;
-    case 9 : c+=k8[8];                      /* fall through */
-    case 8 : b+=k[2]+(((uint32_t)k[3])<<16);
-             a+=k[0]+(((uint32_t)k[1])<<16);
-             break;
-    case 7 : b+=((uint32_t)k8[6])<<16;      /* fall through */
-    case 6 : b+=k[2];
-             a+=k[0]+(((uint32_t)k[1])<<16);
-             break;
-    case 5 : b+=k8[4];                      /* fall through */
-    case 4 : a+=k[0]+(((uint32_t)k[1])<<16);
-             break;
-    case 3 : a+=((uint32_t)k8[2])<<16;      /* fall through */
-    case 2 : a+=k[0];
-             break;
-    case 1 : a+=k8[0];
-             break;
-    case 0 : *pc=c; *pb=b; return;  /* zero length strings require no mixing */
-    }
-
-  } else {                        /* need to read the key one byte at a time */
-    const uint8_t *k = (const uint8_t *)key;
-
-    /*--------------- all but the last block: affect some 32 bits of (a,b,c) */
-    while (length > 12)
-    {
-      a += k[0];
-      a += ((uint32_t)k[1])<<8;
-      a += ((uint32_t)k[2])<<16;
-      a += ((uint32_t)k[3])<<24;
-      b += k[4];
-      b += ((uint32_t)k[5])<<8;
-      b += ((uint32_t)k[6])<<16;
-      b += ((uint32_t)k[7])<<24;
-      c += k[8];
-      c += ((uint32_t)k[9])<<8;
-      c += ((uint32_t)k[10])<<16;
-      c += ((uint32_t)k[11])<<24;
-      mix(a,b,c);
-      length -= 12;
-      k += 12;
-    }
-
-    /*-------------------------------- last block: affect all 32 bits of (c) */
-    switch(length)                   /* all the case statements fall through */
-    {
-    case 12: c+=((uint32_t)k[11])<<24;
-    case 11: c+=((uint32_t)k[10])<<16;
-    case 10: c+=((uint32_t)k[9])<<8;
-    case 9 : c+=k[8];
-    case 8 : b+=((uint32_t)k[7])<<24;
-    case 7 : b+=((uint32_t)k[6])<<16;
-    case 6 : b+=((uint32_t)k[5])<<8;
-    case 5 : b+=k[4];
-    case 4 : a+=((uint32_t)k[3])<<24;
-    case 3 : a+=((uint32_t)k[2])<<16;
-    case 2 : a+=((uint32_t)k[1])<<8;
-    case 1 : a+=k[0];
-             break;
-    case 0 : *pc=c; *pb=b; return;  /* zero length strings require no mixing */
-    }
-  }
-
-  final(a,b,c);
-  *pc=c; *pb=b;
-}
-#endif
-
-
 /*
  * hashbig():
  * This is the same as hash_word() on big-endian machines.  It is different
  * from hashlittle() on all machines.  hashbig() takes advantage of
  * big-endian byte ordering. 
  */
-static uint32_t hashbig( const void *key, size_t length, uint32_t initval)
+static uint32_t hashbig( const void *key, size_t length, uint32_t *val2)
 {
   uint32_t a,b,c;
   union { const void *ptr; size_t i; } u; /* to cast key to (size_t) happily */
 
   /* Set up the internal state */
-  a = b = c = 0xdeadbeef + ((uint32_t)length) + initval;
+  a = b = c = 0xdeadbeef + ((uint32_t)length) + *val2;
 
   u.ptr = key;
   if (HASH_BIG_ENDIAN && ((u.i & 0x3) == 0)) {
@@ -768,6 +535,7 @@ static uint32_t hashbig( const void *key, size_t length, uint32_t initval)
   }
 
   final(a,b,c);
+  *val2 = b;
   return c;
 }
 
@@ -775,7 +543,7 @@ static uint32_t hashbig( const void *key, size_t length, uint32_t initval)
  * element.  This delivers least-surprise: hash such as "int arr[] = {
  * 1, 2 }; hash_stable(arr, 2, 0);" will be the same on big and little
  * endian machines, even though a bytewise hash wouldn't be. */
-uint32_t hash_stable_64(const void *key, size_t n, uint32_t base)
+uint64_t hash64_stable_64(const void *key, size_t n, uint32_t base)
 {
 	const uint64_t *k = key;
 	uint32_t a,b,c;
@@ -811,10 +579,10 @@ uint32_t hash_stable_64(const void *key, size_t n, uint32_t base)
 		return c;
 	}
 	final(a,b,c);
-	return c;
+	return ((uint64_t)b << 32) | c;
 }
 
-uint32_t hash_stable_32(const void *key, size_t n, uint32_t base)
+uint64_t hash64_stable_32(const void *key, size_t n, uint32_t base)
 {
 	const uint32_t *k = key;
 	uint32_t a,b,c;
@@ -841,10 +609,10 @@ uint32_t hash_stable_32(const void *key, size_t n, uint32_t base)
 		return c;
 	}
 	final(a,b,c);
-	return c;
+	return ((uint64_t)b << 32) | c;
 }
 
-uint32_t hash_stable_16(const void *key, size_t n, uint32_t base)
+uint64_t hash64_stable_16(const void *key, size_t n, uint32_t base)
 {
 	const uint16_t *k = key;
 	uint32_t a,b,c;
@@ -878,20 +646,56 @@ uint32_t hash_stable_16(const void *key, size_t n, uint32_t base)
 		return c;
 	}
 	final(a,b,c);
-	return c;
+	return ((uint64_t)b << 32) | c;
 }
 	
-uint32_t hash_stable_8(const void *key, size_t n, uint32_t base)
+uint64_t hash64_stable_8(const void *key, size_t n, uint32_t base)
 {
-	return hashlittle(key, n, base);
+	uint32_t lower = hashlittle(key, n, &base);
+
+	return ((uint64_t)base << 32) | lower;	
 }
 
 uint32_t hash_any(const void *key, size_t length, uint32_t base)
 {
 	if (HASH_BIG_ENDIAN)
-		return hashbig(key, length, base);
+		return hashbig(key, length, &base);
 	else
-		return hashlittle(key, length, base);
+		return hashlittle(key, length, &base);
+}
+
+uint32_t hash_stable_64(const void *key, size_t n, uint32_t base)
+{
+	return hash64_stable_64(key, n, base);
+}
+
+uint32_t hash_stable_32(const void *key, size_t n, uint32_t base)
+{
+	return hash64_stable_32(key, n, base);
+}
+
+uint32_t hash_stable_16(const void *key, size_t n, uint32_t base)
+{
+	return hash64_stable_16(key, n, base);
+}
+
+uint32_t hash_stable_8(const void *key, size_t n, uint32_t base)
+{
+	return hashlittle(key, n, &base);
+}
+
+/* Jenkins' lookup8 is a 64 bit hash, but he says it's obsolete.  Use
+ * the plain one and recombine into 64 bits. */
+uint64_t hash64_any(const void *key, size_t length, uint32_t base)
+{
+	uint32_t lower;
+
+	if (HASH_BIG_ENDIAN)
+		lower = hashbig(key, length, &base);
+	else
+		lower = hashlittle(key, length, &base);
+
+	return ((uint64_t)base << 32) | lower;
 }
 
 #ifdef SELF_TEST

ccan/hash/hash.h

@@ -3,6 +3,7 @@
 #include <stdint.h>
 #include <stdlib.h>
 #include "config.h"
+#include <ccan/build_assert/build_assert.h>
 
 /* Stolen mostly from: lookup3.c, by Bob Jenkins, May 2006, Public Domain.
  * 
@@ -25,7 +26,7 @@
  * It may also change with future versions: it could even detect at runtime
  * what the fastest hash to use is.
  *
- * See also: hash_stable.
+ * See also: hash64, hash_stable.
  *
  * Example:
  *	#include "hash/hash.h"
@@ -69,6 +70,9 @@
  * memory representations of integers depend on the machine
  * endianness.
  *
+ * See also:
+ *	hash64_stable
+ *
  * Example:
  *	#include "hash/hash.h"
  *	#include <err.h>
@@ -85,11 +89,12 @@
  *	}
  */
 #define hash_stable(p, num, base)					\
-	(sizeof(*(p)) == 8 ? hash_stable_64((p), (num), (base))		\
+	(EXPR_BUILD_ASSERT(sizeof(*(p)) == 8 || sizeof(*(p)) == 4	\
+			   || sizeof(*(p)) == 2 || sizeof(*(p)) == 1) +	\
+	 sizeof(*(p)) == 8 ? hash_stable_64((p), (num), (base))		\
 	 : sizeof(*(p)) == 4 ? hash_stable_32((p), (num), (base))	\
 	 : sizeof(*(p)) == 2 ? hash_stable_16((p), (num), (base))	\
-	 : sizeof(*(p)) == 1 ? hash_stable_8((p), (num), (base))	\
-	 : hash_stable_fail((p), (num), sizeof(*(p)), (base)))
+	 : hash_stable_8((p), (num), (base)))
 
 /**
  * hash_u32 - fast hash an array of 32-bit values for internal use
@@ -107,6 +112,18 @@
  */
 uint32_t hash_u32(const uint32_t *key, size_t num, uint32_t base);
 
+/* Our underlying operations. */
+uint32_t hash_any(const void *key, size_t length, uint32_t base);
+uint32_t hash_stable_64(const void *key, size_t n, uint32_t base);
+uint32_t hash_stable_32(const void *key, size_t n, uint32_t base);
+uint32_t hash_stable_16(const void *key, size_t n, uint32_t base);
+uint32_t hash_stable_8(const void *key, size_t n, uint32_t base);
+uint64_t hash64_any(const void *key, size_t length, uint32_t base);
+uint64_t hash64_stable_64(const void *key, size_t n, uint32_t base);
+uint64_t hash64_stable_32(const void *key, size_t n, uint32_t base);
+uint64_t hash64_stable_16(const void *key, size_t n, uint32_t base);
+uint64_t hash64_stable_8(const void *key, size_t n, uint32_t base);
+
 /**
  * hash_string - very fast hash of an ascii string
  * @str: the nul-terminated string
@@ -132,14 +149,6 @@ static inline uint32_t hash_string(const char *string)
 	return ret;
 }
 
-/* Our underlying operations. */
-uint32_t hash_any(const void *key, size_t length, uint32_t base);
-uint32_t hash_stable_64(const void *key, size_t n, uint32_t base);
-uint32_t hash_stable_32(const void *key, size_t n, uint32_t base);
-uint32_t hash_stable_16(const void *key, size_t n, uint32_t base);
-uint32_t hash_stable_8(const void *key, size_t n, uint32_t base);
-uint32_t hash_stable_fail(const void *key, size_t n, size_t len, uint32_t base);
-
 /**
  * hash_pointer - hash a pointer for internal use
  * @p: the pointer value to hash
@@ -195,4 +204,106 @@ static inline uint32_t hash_pointer(const void *p, uint32_t base)
 	} else
 		return hash(&p, 1, base);
 }
+
+/**
+ * hash64 - fast 64-bit hash of an array for internal use
+ * @p: the array or pointer to first element
+ * @num: the number of elements to hash
+ * @base: the base number to roll into the hash (usually 0)
+ *
+ * The memory region pointed to by p is combined with the base to form
+ * a 64-bit hash.
+ *
+ * This hash will have different results on different machines, so is
+ * only useful for internal hashes (ie. not hashes sent across the
+ * network or saved to disk).
+ *
+ * It may also change with future versions: it could even detect at runtime
+ * what the fastest hash to use is.
+ *
+ * See also: hash.
+ *
+ * Example:
+ *	#include <ccan/hash/hash.h>
+ *	#include <err.h>
+ *	#include <stdio.h>
+ *
+ *	// Simple demonstration: idential strings will have the same hash, but
+ *	// two different strings will probably not.
+ *	int main(int argc, char *argv[])
+ *	{
+ *		uint64_t hash1, hash2;
+ *
+ *		if (argc != 3)
+ *			err(1, "Usage: %s <string1> <string2>", argv[0]);
+ *
+ *		hash1 = hash64(argv[1], strlen(argv[1]), 0);
+ *		hash2 = hash64(argv[2], strlen(argv[2]), 0);
+ *		printf("Hash is %s\n", hash1 == hash2 ? "same" : "different");
+ *		return 0;
+ *	}
+ */
+#define hash64(p, num, base) hash64_any((p), (num)*sizeof(*(p)), (base))
+
+/**
+ * hash64_stable - 64 bit hash of an array for external use
+ * @p: the array or pointer to first element
+ * @num: the number of elements to hash
+ * @base: the base number to roll into the hash (usually 0)
+ *
+ * The array of simple integer types pointed to by p is combined with
+ * the base to form a 64-bit hash.
+ *
+ * This hash will have the same results on different machines, so can
+ * be used for external hashes (ie. hashes sent across the network or
+ * saved to disk).  The results will not change in future versions of
+ * this module.
+ *
+ * Note that it is only legal to hand an array of simple integer types
+ * to this hash (ie. char, uint16_t, int64_t, etc).  In these cases,
+ * the same values will have the same hash result, even though the
+ * memory representations of integers depend on the machine
+ * endianness.
+ *
+ * See also:
+ *	hash_stable
+ *
+ * Example:
+ *	#include <ccan/hash/hash.h>
+ *	#include <err.h>
+ *	#include <stdio.h>
+ *
+ *	int main(int argc, char *argv[])
+ *	{
+ *		if (argc != 2)
+ *			err(1, "Usage: %s <string-to-hash>", argv[0]);
+ *
+ *		printf("Hash stable result is %llu\n",
+ *		       (long long)hash64_stable(argv[1], strlen(argv[1]), 0));
+ *		return 0;
+ *	}
+ */
+#define hash64_stable(p, num, base)					\
+	(EXPR_BUILD_ASSERT(sizeof(*(p)) == 8 || sizeof(*(p)) == 4	\
+			   || sizeof(*(p)) == 2 || sizeof(*(p)) == 1) +	\
+	 sizeof(*(p)) == 8 ? hash64_stable_64((p), (num), (base))	\
+	 : sizeof(*(p)) == 4 ? hash64_stable_32((p), (num), (base))	\
+	 : sizeof(*(p)) == 2 ? hash64_stable_16((p), (num), (base))	\
+	 : hash64_stable_8((p), (num), (base)))
+
+
+/**
+ * hashl - fast 32/64-bit hash of an array for internal use
+ * @p: the array or pointer to first element
+ * @num: the number of elements to hash
+ * @base: the base number to roll into the hash (usually 0)
+ *
+ * This is either hash() or hash64(), on 32/64 bit long machines.
+ */
+#define hashl(p, num, base)						\
+	(EXPR_BUILD_ASSERT(sizeof(long) == sizeof(uint32_t)		\
+			   || sizeof(long) == sizeof(uint64_t)) +	\
+	(sizeof(long) == sizeof(uint64_t)				\
+	 ? hash64((p), (num), (base)) : hash((p), (num), (base))))
+
 #endif /* HASH_H */

ccan/hash/test/api-hash_stable.c

@@ -21,7 +21,7 @@ int main(int argc, char *argv[])
 		u64array[i] = i;
 	}
 
-	plan_tests(132);
+	plan_tests(264);
 
 	/* hash_stable is API-guaranteed. */
 	ok1(hash_stable(u8array, ARRAY_WORDS, 0) == 0x1d4833cc);
@@ -160,5 +160,141 @@ int main(int argc, char *argv[])
 	ok1(hash_stable(u64array, ARRAY_WORDS, 1073741824) == 0x1b346394);
 	ok1(hash_stable(u64array, ARRAY_WORDS, 2147483648U) == 0x6c3a1592);
 
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 0) == 16887282882572727244ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 1) == 12032777473133454818ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 2) == 18183407363221487738ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 4) == 17860764172704150171ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 8) == 18076051600675559233ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 16) == 9909361918431556721ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 32) == 12937969888744675813ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 64) == 5245669057381736951ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 128) == 4376874646406519665ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 256) == 14219974419871569521ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 512) == 2263415354134458951ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 1024) == 4953859694526221685ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 2048) == 3432228642067641593ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 4096) == 1219647244417697483ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 8192) == 7629939424585859553ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 16384) == 10041660531376789749ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 32768) == 13859885793922603927ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 65536) == 15069060338344675120ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 131072) == 818163430835601100ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 262144) == 14914314323019517069ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 524288) == 17518437749769352214ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 1048576) == 14920048004901212706ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 2097152) == 8758567366332536138ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 4194304) == 6226655736088907885ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 8388608) == 13716650013685832100ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 16777216) == 305325651636315638ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 33554432) == 16784147606583781671ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 67108864) == 16509467555140798205ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 134217728) == 8717281234694060584ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 268435456) == 8098476701725660537ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 536870912) == 16345871539461094006ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 1073741824) == 3755557000429964408ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 2147483648U) == 15017348801959710081ULL);
+
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 0) == 1038028831307724039ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 1) == 10155473272642627302ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 2) == 5714751190106841420ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 4) == 3923885607767527866ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 8) == 3931017318293995558ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 16) == 1469696588339313177ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 32) == 11522218526952715051ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 64) == 6953517591561958496ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 128) == 7406689491740052867ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 256) == 10101844489704093104ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 512) == 12511348870707245959ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 1024) == 1614019938016861468ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 2048) == 5294796182374592721ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 4096) == 16089570706643716675ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 8192) == 1689302638424579464ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 16384) == 1446340172370386893ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 32768) == 16535503506744393039ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 65536) == 3496794142527150328ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 131072) == 6568245367474548504ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 262144) == 9487676460765485949ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 524288) == 4519762130966530000ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 1048576) == 15623412069215340610ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 2097152) == 544013388676438108ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 4194304) == 5594904760290840266ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 8388608) == 18098755780041592043ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 16777216) == 6389168672387330316ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 33554432) == 896986127732419381ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 67108864) == 13232626471143901354ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 134217728) == 53378562890493093ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 268435456) == 10072361400297824771ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 536870912) == 14511948118285144529ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 1073741824) == 6981033484844447277ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 2147483648U) == 5619339091684126808ULL);
+
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 0) == 3037571077312110476ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 1) == 14732398743825071988ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 2) == 14949132158206672071ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 4) == 1291370080511561429ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 8) == 10792665964172133092ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 16) == 14250138032054339435ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 32) == 17136741522078732741ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 64) == 3260193403318236635ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 128) == 10526616652205653536ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 256) == 9019690373358576579ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 512) == 6997491436599677436ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 1024) == 18302783371416533798ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 2048) == 10149320644446516025ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 4096) == 7073759949410623868ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 8192) == 17442399482223760073ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 16384) == 2983906194216281861ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 32768) == 4975845419129060524ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 65536) == 594019910205413268ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 131072) == 11903010186073691112ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 262144) == 7339636527154847008ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 524288) == 15243305400579108736ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 1048576) == 16737926245392043198ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 2097152) == 15725083267699862972ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 4194304) == 12527834265678833794ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 8388608) == 13908436455987824848ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 16777216) == 9672773345173872588ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 33554432) == 2305314279896710501ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 67108864) == 1866733780381408751ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 134217728) == 11906263969465724709ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 268435456) == 5501594918093830069ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 536870912) == 15823785789276225477ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 1073741824) == 17353000723889475410ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 2147483648U) == 7494736910655503182ULL);
+
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 0) == 9765419389786481410ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 1) == 11182806172127114246ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 2) == 2559155171395472619ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 4) == 3311692033324815378ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 8) == 1297175419505333844ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 16) == 617896928653569210ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 32) == 1517398559958603553ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 64) == 4504821917445110758ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 128) == 1971743331114904452ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 256) == 6177667912354374306ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 512) == 15570521289777792458ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 1024) == 9204559632415917331ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 2048) == 9008982669760028237ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 4096) == 14803537660281700281ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 8192) == 2873966517448487327ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 16384) == 5859277625928363661ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 32768) == 15520461285618185970ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 65536) == 16746489793331175369ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 131072) == 514952025484227461ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 262144) == 10867212269810675249ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 524288) == 9822204377278314587ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 1048576) == 3295088921987850465ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 2097152) == 7559197431498053712ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 4194304) == 1667267269116771849ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 8388608) == 2916804068951374862ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 16777216) == 14422558383125688561ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 33554432) == 10083112683694342602ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 67108864) == 7222777647078298513ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 134217728) == 18424513674048212529ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 268435456) == 14913668581101810784ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 536870912) == 14377721174297902048ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 1073741824) == 6031715005667500948ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 2147483648U) == 4827100319722378642ULL);
+
 	return exit_status();
 }

ccan/hash/test/run.c

@@ -17,7 +17,7 @@ int main(int argc, char *argv[])
 	for (i = 0; i < ARRAY_WORDS; i++)
 		array[i] = i;
 
-	plan_tests(22);
+	plan_tests(39);
 	/* Hash should be the same, indep of memory alignment. */
 	val = hash(array, sizeof(array), 0);
 	for (i = 0; i < sizeof(uint32_t); i++) {
@@ -51,6 +51,31 @@ int main(int argc, char *argv[])
 		diag("Byte %i, range %u-%u", i, lowest, highest);
 	}
 
+	/* Hash of random values should have random distribution:
+	 * check one byte at a time. */
+	for (i = 0; i < sizeof(uint64_t); i++) {
+		unsigned int lowest = -1U, highest = 0;
+
+		memset(results, 0, sizeof(results));
+
+		for (j = 0; j < 256000; j++) {
+			for (k = 0; k < ARRAY_WORDS; k++)
+				array[k] = random();
+			results[(hash64(array, sizeof(array), 0) >> i*8)&0xFF]++;
+		}
+
+		for (j = 0; j < 256; j++) {
+			if (results[j] < lowest)
+				lowest = results[j];
+			if (results[j] > highest)
+				highest = results[j];
+		}
+		/* Expect within 20% */
+		ok(lowest > 800, "Byte %i lowest %i", i, lowest);
+		ok(highest < 1200, "Byte %i highest %i", i, highest);
+		diag("Byte %i, range %u-%u", i, lowest, highest);
+	}
+
 	/* Hash of pointer values should also have random distribution. */
 	for (i = 0; i < sizeof(uint32_t); i++) {
 		unsigned int lowest = -1U, highest = 0;
@@ -75,6 +100,13 @@ int main(int argc, char *argv[])
 		diag("hash_pointer byte %i, range %u-%u", i, lowest, highest);
 	}
 
+	if (sizeof(long) == sizeof(uint32_t))
+		ok1(hashl(array, sizeof(array), 0)
+		    == hash(array, sizeof(array), 0));
+	else
+		ok1(hashl(array, sizeof(array), 0)
+		    == hash64(array, sizeof(array), 0));
+
 	/* String hash: weak, so only test bottom byte */
 	for (i = 0; i < 1; i++) {
 		unsigned int num = 0, cursor, lowest = -1U, highest = 0;