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-rw-r--r--lib/floatundidf.c84
1 files changed, 45 insertions, 39 deletions
diff --git a/lib/floatundidf.c b/lib/floatundidf.c
index 708d614ac..1f304c5c3 100644
--- a/lib/floatundidf.c
+++ b/lib/floatundidf.c
@@ -1,29 +1,33 @@
-//===-- floatundidf.c - Implement __floatundidf ---------------------------===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file implements __floatundidf for the compiler_rt library.
-//
-//===----------------------------------------------------------------------===//
+/* ===-- floatundidf.c - Implement __floatundidf ---------------------------===
+ *
+ * The LLVM Compiler Infrastructure
+ *
+ * This file is distributed under the University of Illinois Open Source
+ * License. See LICENSE.TXT for details.
+ *
+ * ===----------------------------------------------------------------------===
+ *
+ * This file implements __floatundidf for the compiler_rt library.
+ *
+ * ===----------------------------------------------------------------------===
+ */
#include "int_lib.h"
#include <float.h>
-// Returns: convert a to a double, rounding toward even.
+/* Returns: convert a to a double, rounding toward even. */
-// Assumption: double is a IEEE 64 bit floating point type
-// du_int is a 64 bit integral type
+/* Assumption: double is a IEEE 64 bit floating point type
+ * du_int is a 64 bit integral type
+ */
-// seee eeee eeee mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm
+/* seee eeee eeee mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm */
#ifndef __SOFT_FP__
-// Support for systems that have hardware floating-point; we'll set the inexact flag
-// as a side-effect of this computation.
+/* Support for systems that have hardware floating-point; we'll set the inexact flag
+ * as a side-effect of this computation.
+ */
+
#include <stdint.h>
double
@@ -44,8 +48,9 @@ __floatundidf(du_int a)
}
#else
-// Support for systems that don't have hardware floating-point; there are no flags to
-// set, and we don't want to code-gen to an unknown soft-float implementation.
+/* Support for systems that don't have hardware floating-point; there are no flags to
+ * set, and we don't want to code-gen to an unknown soft-float implementation.
+ */
double
__floatundidf(du_int a)
@@ -53,17 +58,18 @@ __floatundidf(du_int a)
if (a == 0)
return 0.0;
const unsigned N = sizeof(du_int) * CHAR_BIT;
- int sd = N - __builtin_clzll(a); // number of significant digits
- int e = sd - 1; // exponent
+ int sd = N - __builtin_clzll(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
+ /* 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:
@@ -75,27 +81,27 @@ __floatundidf(du_int a)
a = (a >> (sd - (DBL_MANT_DIG+2))) |
((a & ((du_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
+ /* 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 & ((du_int)1 << DBL_MANT_DIG))
{
a >>= 1;
++e;
}
- // a is now rounded to DBL_MANT_DIG bits
+ /* a is now rounded to DBL_MANT_DIG bits */
}
else
{
a <<= (DBL_MANT_DIG - sd);
- // a is now rounded to DBL_MANT_DIG bits
+ /* a is now rounded to DBL_MANT_DIG bits */
}
double_bits fb;
- fb.u.high = ((e + 1023) << 20) | // exponent
- ((su_int)(a >> 32) & 0x000FFFFF); // mantissa-high
- fb.u.low = (su_int)a; // mantissa-low
+ fb.u.high = ((e + 1023) << 20) | /* exponent */
+ ((su_int)(a >> 32) & 0x000FFFFF); /* mantissa-high */
+ fb.u.low = (su_int)a; /* mantissa-low */
return fb.f;
}
#endif