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-rw-r--r--lib/floatuntidf.c82
1 files changed, 0 insertions, 82 deletions
diff --git a/lib/floatuntidf.c b/lib/floatuntidf.c
deleted file mode 100644
index 4c1d3289f511..000000000000
--- a/lib/floatuntidf.c
+++ /dev/null
@@ -1,82 +0,0 @@
-/* ===-- floatuntidf.c - Implement __floatuntidf ---------------------------===
- *
- * The LLVM Compiler Infrastructure
- *
- * This file is dual licensed under the MIT and the University of Illinois Open
- * Source Licenses. See LICENSE.TXT for details.
- *
- * ===----------------------------------------------------------------------===
- *
- * This file implements __floatuntidf for the compiler_rt library.
- *
- * ===----------------------------------------------------------------------===
- */
-
-#include "int_lib.h"
-
-#if __x86_64
-
-/* Returns: convert a to a double, rounding toward even. */
-
-/* Assumption: double is a IEEE 64 bit floating point type
- * tu_int is a 128 bit integral type
- */
-
-/* seee eeee eeee mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm */
-
-si_int __clzti2(ti_int a);
-
-double
-__floatuntidf(tu_int a)
-{
- if (a == 0)
- return 0.0;
- const unsigned N = sizeof(tu_int) * CHAR_BIT;
- int sd = N - __clzti2(a); /* number of significant digits */
- int e = sd - 1; /* exponent */
- if (sd > DBL_MANT_DIG)
- {
- /* start: 0000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQxxxxxxxxxxxxxxxxxx
- * finish: 000000000000000000000000000000000000001xxxxxxxxxxxxxxxxxxxxxxPQR
- * 12345678901234567890123456
- * 1 = msb 1 bit
- * P = bit DBL_MANT_DIG-1 bits to the right of 1
- * Q = bit DBL_MANT_DIG bits to the right of 1
- * R = "or" of all bits to the right of Q
- */
- switch (sd)
- {
- case DBL_MANT_DIG + 1:
- a <<= 1;
- break;
- case DBL_MANT_DIG + 2:
- break;
- default:
- a = (a >> (sd - (DBL_MANT_DIG+2))) |
- ((a & ((tu_int)(-1) >> ((N + DBL_MANT_DIG+2) - sd))) != 0);
- };
- /* finish: */
- a |= (a & 4) != 0; /* Or P into R */
- ++a; /* round - this step may add a significant bit */
- a >>= 2; /* dump Q and R */
- /* a is now rounded to DBL_MANT_DIG or DBL_MANT_DIG+1 bits */
- if (a & ((tu_int)1 << DBL_MANT_DIG))
- {
- a >>= 1;
- ++e;
- }
- /* a is now rounded to DBL_MANT_DIG bits */
- }
- else
- {
- a <<= (DBL_MANT_DIG - sd);
- /* a is now rounded to DBL_MANT_DIG bits */
- }
- double_bits fb;
- fb.u.s.high = ((e + 1023) << 20) | /* exponent */
- ((su_int)(a >> 32) & 0x000FFFFF); /* mantissa-high */
- fb.u.s.low = (su_int)a; /* mantissa-low */
- return fb.f;
-}
-
-#endif