X-Git-Url: http://git.hcoop.net/bpt/guile.git/blobdiff_plain/54cbf8c6dcae9fe4925186c6f46718e7b45932fe..1fc3fc11ffea3b5c0b1844306244b3f4a52c1067:/libguile/numbers.h

diff --git a/libguile/numbers.h b/libguile/numbers.h
index cef2b863b..bba336bd4 100644
--- a/libguile/numbers.h
+++ b/libguile/numbers.h
@@ -3,7 +3,8 @@
 #ifndef SCM_NUMBERS_H
 #define SCM_NUMBERS_H
 
-/* Copyright (C) 1995,1996,1998,2000,2001,2002,2003,2004,2005, 2006, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
+/* Copyright (C) 1995,1996,1998,2000,2001,2002,2003,2004,2005, 2006,
+ *   2008, 2009, 2010, 2011, 2013, 2014 Free Software Foundation, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public License
@@ -48,19 +49,43 @@ typedef scm_t_int32 scm_t_wchar;
 #define SCM_MOST_POSITIVE_FIXNUM ((SCM_T_SIGNED_BITS_MAX-3)/4)
 #define SCM_MOST_NEGATIVE_FIXNUM (-SCM_MOST_POSITIVE_FIXNUM-1)
 
-/* SCM_SRS is signed right shift */
-#if (-1 == (((-1) << 2) + 2) >> 2)
-# define SCM_SRS(x, y) ((x) >> (y))
+/* SCM_SRS (X, Y) is signed right shift, defined as floor (X / 2^Y),
+   where Y must be non-negative and less than the width in bits of X.
+   It's common for >> to do this, but the C standards do not specify
+   what happens when X is negative.
+
+   NOTE: X must not perform side effects.  */
+#if (-1 >> 2 == -1) && (-4 >> 2 == -1) && (-5 >> 2 == -2) && (-8 >> 2 == -2)
+# define SCM_SRS(x, y)  ((x) >> (y))
 #else
-# define SCM_SRS(x, y) ((x) < 0 ? ~((~(x)) >> (y)) : ((x) >> (y)))
-#endif /* (-1 == (((-1) << 2) + 2) >> 2) */
+# define SCM_SRS(x, y)                                   \
+  ((x) < 0                                               \
+   ? -1 - (scm_t_signed_bits) (~(scm_t_bits)(x) >> (y))  \
+   : ((x) >> (y)))
+#endif
+
 
+/* The first implementation of SCM_I_INUM below depends on behavior that
+   is specified by GNU C but not by C standards, namely that when
+   casting to a signed integer of width N, the value is reduced modulo
+   2^N to be within range of the type.  The second implementation below
+   should be portable to all conforming C implementations, but may be
+   less efficient if the compiler is not sufficiently clever.
+
+   NOTE: X must not perform side effects.  */
+#ifdef __GNUC__
+# define SCM_I_INUM(x)  (SCM_SRS ((scm_t_signed_bits) SCM_UNPACK (x), 2))
+#else
+# define SCM_I_INUM(x)                                \
+  (SCM_UNPACK (x) > LONG_MAX                          \
+   ? -1 - (scm_t_signed_bits) (~SCM_UNPACK (x) >> 2)  \
+   : (scm_t_signed_bits) (SCM_UNPACK (x) >> 2))
+#endif
 
 #define SCM_I_INUMP(x)	(2 & SCM_UNPACK (x))
 #define SCM_I_NINUMP(x) (!SCM_I_INUMP (x))
 #define SCM_I_MAKINUM(x) \
-  (SCM_PACK ((((scm_t_signed_bits) (x)) << 2) + scm_tc2_int))
-#define SCM_I_INUM(x)   (SCM_SRS ((scm_t_signed_bits) SCM_UNPACK (x), 2))
+  (SCM_PACK ((((scm_t_bits) (x)) << 2) + scm_tc2_int))
 
 /* SCM_FIXABLE is true if its long argument can be encoded in an SCM_INUM. */
 #define SCM_POSFIXABLE(n) ((n) <= SCM_MOST_POSITIVE_FIXNUM)
@@ -204,7 +229,8 @@ SCM_API SCM scm_logbit_p (SCM n1, SCM n2);
 SCM_API SCM scm_lognot (SCM n);
 SCM_API SCM scm_modulo_expt (SCM n, SCM k, SCM m);
 SCM_API SCM scm_integer_expt (SCM z1, SCM z2);
-SCM_API SCM scm_ash (SCM n, SCM cnt);
+SCM_API SCM scm_ash (SCM n, SCM count);
+SCM_API SCM scm_round_ash (SCM n, SCM count);
 SCM_API SCM scm_bit_extract (SCM n, SCM start, SCM end);
 SCM_API SCM scm_logcount (SCM n);
 SCM_API SCM scm_integer_length (SCM n);
@@ -240,6 +266,7 @@ SCM_API SCM scm_complex_p (SCM x);
 SCM_API SCM scm_real_p (SCM x);
 SCM_API SCM scm_rational_p (SCM z);
 SCM_API SCM scm_integer_p (SCM x);
+SCM_API SCM scm_exact_integer_p (SCM x);
 SCM_API SCM scm_inexact_p (SCM x);
 SCM_API int scm_is_inexact (SCM x);
 SCM_API SCM scm_num_eq_p (SCM x, SCM y);
@@ -328,6 +355,7 @@ SCM_INTERNAL void scm_i_print_complex (double real, double imag, SCM port);
 /* conversion functions for integers */
 
 SCM_API int scm_is_integer (SCM val);
+SCM_API int scm_is_exact_integer (SCM val);
 SCM_API int scm_is_signed_integer (SCM val,
 				   scm_t_intmax min, scm_t_intmax max);
 SCM_API int scm_is_unsigned_integer (SCM val,
@@ -500,6 +528,46 @@ SCM_API SCM  scm_from_mpz (mpz_t rop);
 #endif
 #endif
 
+#if SCM_SIZEOF_SCM_T_PTRDIFF == 4
+#define scm_to_ptrdiff_t    scm_to_int32
+#define scm_from_ptrdiff_t  scm_from_int32
+#else
+#if SCM_SIZEOF_SCM_T_PTRDIFF == 8
+#define scm_to_ptrdiff_t    scm_to_int64
+#define scm_from_ptrdiff_t  scm_from_int64
+#else
+#error sizeof(scm_t_ptrdiff) is not 4 or 8.
+#endif
+#endif
+
+#if SCM_SIZEOF_INTPTR_T == 0
+/* No intptr_t; use size_t functions. */
+#define scm_to_intptr_t   scm_to_ssize_t
+#define scm_from_intptr_t scm_from_ssize_t
+#elif SCM_SIZEOF_INTPTR_T == 4
+#define scm_to_intptr_t   scm_to_int32
+#define scm_from_intptr_t scm_from_int32
+#elif SCM_SIZEOF_INTPTR_T == 8
+#define scm_to_intptr_t   scm_to_int64
+#define scm_from_intptr_t scm_from_int64
+#else
+#error sizeof(intptr_t) is not 4 or 8.
+#endif
+
+#if SCM_SIZEOF_UINTPTR_T == 0
+/* No uintptr_t; use size_t functions. */
+#define scm_to_uintptr_t   scm_to_size_t
+#define scm_from_uintptr_t scm_from_size_t
+#elif SCM_SIZEOF_UINTPTR_T == 4
+#define scm_to_uintptr_t   scm_to_uint32
+#define scm_from_uintptr_t scm_from_uint32
+#elif SCM_SIZEOF_UINTPTR_T == 8
+#define scm_to_uintptr_t   scm_to_uint64
+#define scm_from_uintptr_t scm_from_uint64
+#else
+#error sizeof(uintptr_t) is not 4 or 8.
+#endif
+
 /* conversion functions for double */
 
 SCM_API int scm_is_real (SCM val);