X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=lib%2Ffrexp.c;h=37ea13aa84cc009760b639ee181c1c30489ec995;hb=659cae49714b93487242525dfa0e5737463d78d8;hp=7e1f5d1ad48e07de95943f3fd6d3664dda8df109;hpb=c7e61475680fa226bd9b8bdd469cd66914e630f5;p=debian%2Fgzip
diff --git a/lib/frexp.c b/lib/frexp.c
index 7e1f5d1..37ea13a 100644
--- a/lib/frexp.c
+++ b/lib/frexp.c
@@ -1,5 +1,5 @@
/* Split a double into fraction and mantissa.
- Copyright (C) 2007-2008 Free Software Foundation, Inc.
+ Copyright (C) 2007-2018 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@@ -12,12 +12,14 @@
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program. If not, see . */
+ along with this program. If not, see . */
/* Written by Paolo Bonzini , 2003, and
Bruno Haible , 2007. */
-#include
+#if ! defined USE_LONG_DOUBLE
+# include
+#endif
/* Specification. */
#include
@@ -85,73 +87,73 @@ FUNC (DOUBLE x, int *expptr)
exponent = 0;
if (x >= L_(1.0))
{
- /* A positive exponent. */
- DOUBLE pow2_i; /* = pow2[i] */
- DOUBLE powh_i; /* = powh[i] */
-
- /* Invariants: pow2_i = 2^2^i, powh_i = 2^-2^i,
- x * 2^exponent = argument, x >= 1.0. */
- for (i = 0, pow2_i = L_(2.0), powh_i = L_(0.5);
- ;
- i++, pow2_i = pow2_i * pow2_i, powh_i = powh_i * powh_i)
- {
- if (x >= pow2_i)
- {
- exponent += (1 << i);
- x *= powh_i;
- }
- else
- break;
-
- pow2[i] = pow2_i;
- powh[i] = powh_i;
- }
- /* Avoid making x too small, as it could become a denormalized
- number and thus lose precision. */
- while (i > 0 && x < pow2[i - 1])
- {
- i--;
- powh_i = powh[i];
- }
- exponent += (1 << i);
- x *= powh_i;
- /* Here 2^-2^i <= x < 1.0. */
+ /* A positive exponent. */
+ DOUBLE pow2_i; /* = pow2[i] */
+ DOUBLE powh_i; /* = powh[i] */
+
+ /* Invariants: pow2_i = 2^2^i, powh_i = 2^-2^i,
+ x * 2^exponent = argument, x >= 1.0. */
+ for (i = 0, pow2_i = L_(2.0), powh_i = L_(0.5);
+ ;
+ i++, pow2_i = pow2_i * pow2_i, powh_i = powh_i * powh_i)
+ {
+ if (x >= pow2_i)
+ {
+ exponent += (1 << i);
+ x *= powh_i;
+ }
+ else
+ break;
+
+ pow2[i] = pow2_i;
+ powh[i] = powh_i;
+ }
+ /* Avoid making x too small, as it could become a denormalized
+ number and thus lose precision. */
+ while (i > 0 && x < pow2[i - 1])
+ {
+ i--;
+ powh_i = powh[i];
+ }
+ exponent += (1 << i);
+ x *= powh_i;
+ /* Here 2^-2^i <= x < 1.0. */
}
else
{
- /* A negative or zero exponent. */
- DOUBLE pow2_i; /* = pow2[i] */
- DOUBLE powh_i; /* = powh[i] */
-
- /* Invariants: pow2_i = 2^2^i, powh_i = 2^-2^i,
- x * 2^exponent = argument, x < 1.0. */
- for (i = 0, pow2_i = L_(2.0), powh_i = L_(0.5);
- ;
- i++, pow2_i = pow2_i * pow2_i, powh_i = powh_i * powh_i)
- {
- if (x < powh_i)
- {
- exponent -= (1 << i);
- x *= pow2_i;
- }
- else
- break;
-
- pow2[i] = pow2_i;
- powh[i] = powh_i;
- }
- /* Here 2^-2^i <= x < 1.0. */
+ /* A negative or zero exponent. */
+ DOUBLE pow2_i; /* = pow2[i] */
+ DOUBLE powh_i; /* = powh[i] */
+
+ /* Invariants: pow2_i = 2^2^i, powh_i = 2^-2^i,
+ x * 2^exponent = argument, x < 1.0. */
+ for (i = 0, pow2_i = L_(2.0), powh_i = L_(0.5);
+ ;
+ i++, pow2_i = pow2_i * pow2_i, powh_i = powh_i * powh_i)
+ {
+ if (x < powh_i)
+ {
+ exponent -= (1 << i);
+ x *= pow2_i;
+ }
+ else
+ break;
+
+ pow2[i] = pow2_i;
+ powh[i] = powh_i;
+ }
+ /* Here 2^-2^i <= x < 1.0. */
}
/* Invariants: x * 2^exponent = argument, and 2^-2^i <= x < 1.0. */
while (i > 0)
{
- i--;
- if (x < powh[i])
- {
- exponent -= (1 << i);
- x *= pow2[i];
- }
+ i--;
+ if (x < powh[i])
+ {
+ exponent -= (1 << i);
+ x *= pow2[i];
+ }
}
/* Here 0.5 <= x < 1.0. */
}