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authorAndy Wingo <wingo@pobox.com>2010-07-22 21:26:19 +0200
committerAndy Wingo <wingo@pobox.com>2010-07-26 15:01:02 +0200
commitb606ff6af9c9ec7fc3c4473c09ce1e95c18f024a (patch)
tree963d7a600564ccbc6f7bf84fb184c187042f2c78 /libguile/random.c
parent4ca48269976e17b2530728cce7df63843a6ce2b0 (diff)
downloadguile-b606ff6af9c9ec7fc3c4473c09ce1e95c18f024a.tar.gz
low-level RNG interfaces deal in scm_t_uint32, not unsigned long
* libguile/random.h (scm_t_rng): random_bits returns a scm_t_uint32. (scm_i_uniform32, scm_t_i_rstate): Internal RNG returns a scm_t_uint32, as advertised, instead of unsigned long. (scm_c_random): Return a scm_t_uint32 instead of an unsigned long. * libguile/random.c (scm_i_uniform32, scm_i_init_rstate_scm): (scm_i_expose_rstate, scm_c_random, scm_c_random_bignum, scm_random) (scm_init_random): Adapt types to match implementation.
Diffstat (limited to 'libguile/random.c')
-rw-r--r--libguile/random.c82
1 files changed, 28 insertions, 54 deletions
diff --git a/libguile/random.c b/libguile/random.c
index 1350e763a..67928df6d 100644
--- a/libguile/random.c
+++ b/libguile/random.c
@@ -77,7 +77,7 @@ scm_t_rng scm_the_rng;
#define M_PI 3.14159265359
#endif
-unsigned long
+scm_t_uint32
scm_i_uniform32 (scm_t_i_rstate *state)
{
scm_t_uint64 x = (scm_t_uint64) A * state->w + state->c;
@@ -123,15 +123,15 @@ void
scm_i_init_rstate_scm (scm_t_i_rstate *state, SCM value)
#define FUNC_NAME "scm_i_init_rstate_scm"
{
- unsigned long w, c;
+ scm_t_uint32 w, c;
long length;
SCM_VALIDATE_LIST_COPYLEN (SCM_ARG1, value, length);
SCM_ASSERT (length == 3, value, SCM_ARG1, FUNC_NAME);
SCM_ASSERT (scm_is_eq (SCM_CAR (value), scm_i_rstate_tag),
value, SCM_ARG1, FUNC_NAME);
- SCM_VALIDATE_ULONG_COPY (SCM_ARG1, SCM_CADR (value), w);
- SCM_VALIDATE_ULONG_COPY (SCM_ARG1, SCM_CADDR (value), c);
+ SCM_VALIDATE_UINT_COPY (SCM_ARG1, SCM_CADR (value), w);
+ SCM_VALIDATE_UINT_COPY (SCM_ARG1, SCM_CADDR (value), c);
state->w = w;
state->c = c;
@@ -142,8 +142,8 @@ SCM
scm_i_expose_rstate (scm_t_i_rstate *state)
{
return scm_list_3 (scm_i_rstate_tag,
- scm_from_ulong (state->w),
- scm_from_ulong (state->c));
+ scm_from_uint32 (state->w),
+ scm_from_uint32 (state->c));
}
@@ -226,11 +226,10 @@ scm_c_exp1 (scm_t_rstate *state)
unsigned char scm_masktab[256];
-unsigned long
-scm_c_random (scm_t_rstate *state, unsigned long m)
+scm_t_uint32
+scm_c_random (scm_t_rstate *state, scm_t_uint32 m)
{
- unsigned long r, mask;
-#if SCM_SIZEOF_UNSIGNED_LONG == 4
+ scm_t_uint32 r, mask;
mask = (m < 0x100
? scm_masktab[m]
: (m < 0x10000
@@ -239,31 +238,6 @@ scm_c_random (scm_t_rstate *state, unsigned long m)
? scm_masktab[m >> 16] << 16 | 0xffff
: scm_masktab[m >> 24] << 24 | 0xffffff)));
while ((r = scm_the_rng.random_bits (state) & mask) >= m);
-#elif SCM_SIZEOF_UNSIGNED_LONG == 8
- mask = (m < 0x100
- ? scm_masktab[m]
- : (m < 0x10000
- ? scm_masktab[m >> 8] << 8 | 0xff
- : (m < 0x1000000
- ? scm_masktab[m >> 16] << 16 | 0xffff
- : (m < (1UL << 32)
- ? scm_masktab[m >> 24] << 24 | 0xffffff
- : (m < (1UL << 40)
- ? ((unsigned long) scm_masktab[m >> 32] << 32
- | 0xffffffffUL)
- : (m < (1UL << 48)
- ? ((unsigned long) scm_masktab[m >> 40] << 40
- | 0xffffffffffUL)
- : (m < (1UL << 56)
- ? ((unsigned long) scm_masktab[m >> 48] << 48
- | 0xffffffffffffUL)
- : ((unsigned long) scm_masktab[m >> 56] << 56
- | 0xffffffffffffffUL))))))));
- while ((r = ((scm_the_rng.random_bits (state) << 32
- | scm_the_rng.random_bits (state))) & mask) >= m);
-#else
-#error "Cannot deal with this platform's unsigned long size"
-#endif
return r;
}
@@ -287,24 +261,24 @@ scm_c_random_bignum (scm_t_rstate *state, SCM m)
{
SCM result = scm_i_mkbig ();
const size_t m_bits = mpz_sizeinbase (SCM_I_BIG_MPZ (m), 2);
- /* how many bits would only partially fill the last unsigned long? */
- const size_t end_bits = m_bits % (sizeof (unsigned long) * SCM_CHAR_BIT);
- unsigned long *random_chunks = NULL;
- const unsigned long num_full_chunks =
- m_bits / (sizeof (unsigned long) * SCM_CHAR_BIT);
- const unsigned long num_chunks = num_full_chunks + ((end_bits) ? 1 : 0);
+ /* how many bits would only partially fill the last scm_t_uint32? */
+ const size_t end_bits = m_bits % (sizeof (scm_t_uint32) * SCM_CHAR_BIT);
+ scm_t_uint32 *random_chunks = NULL;
+ const scm_t_uint32 num_full_chunks =
+ m_bits / (sizeof (scm_t_uint32) * SCM_CHAR_BIT);
+ const scm_t_uint32 num_chunks = num_full_chunks + ((end_bits) ? 1 : 0);
/* we know the result will be this big */
mpz_realloc2 (SCM_I_BIG_MPZ (result), m_bits);
random_chunks =
- (unsigned long *) scm_gc_calloc (num_chunks * sizeof (unsigned long),
+ (scm_t_uint32 *) scm_gc_calloc (num_chunks * sizeof (scm_t_uint32),
"random bignum chunks");
do
{
- unsigned long *current_chunk = random_chunks + (num_chunks - 1);
- unsigned long chunks_left = num_chunks;
+ scm_t_uint32 *current_chunk = random_chunks + (num_chunks - 1);
+ scm_t_uint32 chunks_left = num_chunks;
mpz_set_ui (SCM_I_BIG_MPZ (result), 0);
@@ -312,24 +286,24 @@ scm_c_random_bignum (scm_t_rstate *state, SCM m)
{
/* generate a mask with ones in the end_bits position, i.e. if
end_bits is 3, then we'd have a mask of ...0000000111 */
- const unsigned long rndbits = scm_the_rng.random_bits (state);
- int rshift = (sizeof (unsigned long) * SCM_CHAR_BIT) - end_bits;
- unsigned long mask = ((unsigned long) ULONG_MAX) >> rshift;
- unsigned long highest_bits = rndbits & mask;
+ const scm_t_uint32 rndbits = scm_the_rng.random_bits (state);
+ int rshift = (sizeof (scm_t_uint32) * SCM_CHAR_BIT) - end_bits;
+ scm_t_uint32 mask = ((scm_t_uint32)-1) >> rshift;
+ scm_t_uint32 highest_bits = rndbits & mask;
*current_chunk-- = highest_bits;
chunks_left--;
}
while (chunks_left)
{
- /* now fill in the remaining unsigned long sized chunks */
+ /* now fill in the remaining scm_t_uint32 sized chunks */
*current_chunk-- = scm_the_rng.random_bits (state);
chunks_left--;
}
mpz_import (SCM_I_BIG_MPZ (result),
num_chunks,
-1,
- sizeof (unsigned long),
+ sizeof (scm_t_uint32),
0,
0,
random_chunks);
@@ -337,7 +311,7 @@ scm_c_random_bignum (scm_t_rstate *state, SCM m)
all bits in order not to get a distorted distribution) */
} while (mpz_cmp (SCM_I_BIG_MPZ (result), SCM_I_BIG_MPZ (m)) >= 0);
scm_gc_free (random_chunks,
- num_chunks * sizeof (unsigned long),
+ num_chunks * sizeof (scm_t_uint32),
"random bignum chunks");
return scm_i_normbig (result);
}
@@ -382,9 +356,9 @@ SCM_DEFINE (scm_random, "random", 1, 1, 0,
SCM_VALIDATE_RSTATE (2, state);
if (SCM_I_INUMP (n))
{
- unsigned long m = SCM_I_INUM (n);
+ scm_t_uint32 m = SCM_I_INUM (n);
SCM_ASSERT_RANGE (1, n, m > 0);
- return scm_from_ulong (scm_c_random (SCM_RSTATE (state), m));
+ return scm_from_uint32 (scm_c_random (SCM_RSTATE (state), m));
}
SCM_VALIDATE_NIM (1, n);
if (SCM_REALP (n))
@@ -644,7 +618,7 @@ scm_init_random ()
scm_t_rng rng =
{
sizeof (scm_t_i_rstate),
- (unsigned long (*)()) scm_i_uniform32,
+ (scm_t_uint32 (*)()) scm_i_uniform32,
(void (*)()) scm_i_init_rstate,
(scm_t_rstate *(*)()) scm_i_copy_rstate,
(void (*)(scm_t_rstate *, SCM)) scm_i_init_rstate_scm,