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-rw-r--r--src/port/rint.c97
1 files changed, 0 insertions, 97 deletions
diff --git a/src/port/rint.c b/src/port/rint.c
deleted file mode 100644
index d59d9ab7743..00000000000
--- a/src/port/rint.c
+++ /dev/null
@@ -1,97 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * rint.c
- * rint() implementation
- *
- * By Pedro Gimeno Fortea, donated to the public domain
- *
- * IDENTIFICATION
- * src/port/rint.c
- *
- *-------------------------------------------------------------------------
- */
-#include "c.h"
-
-#include <math.h>
-
-/*
- * Round to nearest integer, with halfway cases going to the nearest even.
- */
-double
-rint(double x)
-{
- double x_orig;
- double r;
-
- /* Per POSIX, NaNs must be returned unchanged. */
- if (isnan(x))
- return x;
-
- if (x <= 0.0)
- {
- /* Both positive and negative zero should be returned unchanged. */
- if (x == 0.0)
- return x;
-
- /*
- * Subtracting 0.5 from a number very close to -0.5 can round to
- * exactly -1.0, producing incorrect results, so we take the opposite
- * approach: add 0.5 to the negative number, so that it goes closer to
- * zero (or at most to +0.5, which is dealt with next), avoiding the
- * precision issue.
- */
- x_orig = x;
- x += 0.5;
-
- /*
- * Be careful to return minus zero when input+0.5 >= 0, as that's what
- * rint() should return with negative input.
- */
- if (x >= 0.0)
- return -0.0;
-
- /*
- * For very big numbers the input may have no decimals. That case is
- * detected by testing x+0.5 == x+1.0; if that happens, the input is
- * returned unchanged. This also covers the case of minus infinity.
- */
- if (x == x_orig + 1.0)
- return x_orig;
-
- /* Otherwise produce a rounded estimate. */
- r = floor(x);
-
- /*
- * If the rounding did not produce exactly input+0.5 then we're done.
- */
- if (r != x)
- return r;
-
- /*
- * The original fractional part was exactly 0.5 (since
- * floor(input+0.5) == input+0.5). We need to round to nearest even.
- * Dividing input+0.5 by 2, taking the floor and multiplying by 2
- * yields the closest even number. This part assumes that division by
- * 2 is exact, which should be OK because underflow is impossible
- * here: x is an integer.
- */
- return floor(x * 0.5) * 2.0;
- }
- else
- {
- /*
- * The positive case is similar but with signs inverted and using
- * ceil() instead of floor().
- */
- x_orig = x;
- x -= 0.5;
- if (x <= 0.0)
- return 0.0;
- if (x == x_orig - 1.0)
- return x_orig;
- r = ceil(x);
- if (r != x)
- return r;
- return ceil(x * 0.5) * 2.0;
- }
-}