Provide faster bignum-in-fixed-integer range tests in MPI.

* mpi/mpi.c (mp_in_range, mp_in_intptr_range,
mp_in_uintptr_range): New functions.

* mpi/mpi.h (mp_in_range, mp_in_intptr_range,
mp_in_uintptr_range): Declared.

* arith.c (NUM_MAX_MP, INT_PTR_MAX_MP, UINT_PTR_MAX_MP,
INT_PTR_MAX_SUCC_MP): Static variables removed. Note that
INT_PTR_MAX_MP was not used at all!
(normalize): Use mp_in_range instead magnitude comparison to
NUM_MAX_MP.
(in_int_ptr_range, in_uint_ptr_range): Static functions removed.
(c_unum): Use mp_in_uintptr_range instead of
in_uint_ptr_range.
(arith_init): Remove initializations of removed variables.
(arith_free_all): Remove cleanup of removed variables, leaving
function empty.

* lib.c (c_num): Use mp_in_intptr_range instead of
in_int_ptr_range.

2 files changed, 34 insertions, 0 deletions

diff --git a/mpi/mpi.c b/mpi/mpi.c
index ff11f2e2..2097b574 100644
--- a/mpi/mpi.c
+++ b/mpi/mpi.c
@@ -469,6 +469,37 @@ mp_err mp_get_intptr(mp_int *mp, int_ptr_t *z)
   return MP_OKAY;
 }
 
+int mp_in_range(mp_int *mp, uint_ptr_t lim, int unsig)
+{
+  const int ptrnd = (SIZEOF_PTR + MP_DIGIT_BIT - 1) / MP_DIGIT_BIT;
+  mp_size nd = USED(mp);
+
+  if (unsig && ISNEG(mp))
+    return 0;
+
+  if (nd < ptrnd)
+    return 1;
+
+  if (nd > ptrnd)
+    return 0;
+
+  {
+    mp_digit top = DIGITS(mp)[ptrnd - 1];
+    lim >>= ((ptrnd - 1) * MP_DIGIT_BIT);
+    return top <= lim;
+  }
+}
+
+int mp_in_intptr_range(mp_int *mp)
+{
+  return mp_in_range(mp, INT_PTR_MAX, 0);
+}
+
+int mp_in_uintptr_range(mp_int *mp)
+{
+  return mp_in_range(mp, UINT_PTR_MAX, 1);
+}
+
 #ifdef HAVE_DOUBLE_INTPTR_T
 mp_err mp_set_double_intptr(mp_int *mp, double_intptr_t z)
 {
diff --git a/mpi/mpi.h b/mpi/mpi.h
index 28fadb31..71e08055 100644
--- a/mpi/mpi.h
+++ b/mpi/mpi.h
@@ -85,6 +85,9 @@ mp_err mp_set_uintptr(mp_int *mp, uint_ptr_t z);
 mp_err mp_set_intptr(mp_int *mp, int_ptr_t z);
 mp_err mp_get_uintptr(mp_int *mp, uint_ptr_t *z);
 mp_err mp_get_intptr(mp_int *mp, int_ptr_t *z);
+int mp_in_range(mp_int *mp, uint_ptr_t lim, int unsig);
+int mp_in_intptr_range(mp_int *mp);
+int mp_in_uintptr_range(mp_int *mp);
 #ifdef HAVE_DOUBLE_INTPTR_T
 mp_err mp_set_double_intptr(mp_int *mp, double_intptr_t z);
 #endif