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authorThe Android Open Source Project <initial-contribution@android.com>2009-03-03 18:28:13 -0800
committerThe Android Open Source Project <initial-contribution@android.com>2009-03-03 18:28:13 -0800
commit1767f908af327fa388b1c66883760ad851267013 (patch)
tree4b825dc642cb6eb9a060e54bf8d69288fbee4904 /libc/bionic/ldexp.c
parenta799b53f10e5a6fd51fef4436cfb7ec99836a516 (diff)
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auto import from //depot/cupcake/@135843
Diffstat (limited to 'libc/bionic/ldexp.c')
-rw-r--r--libc/bionic/ldexp.c122
1 files changed, 0 insertions, 122 deletions
diff --git a/libc/bionic/ldexp.c b/libc/bionic/ldexp.c
deleted file mode 100644
index ec1f3dd..0000000
--- a/libc/bionic/ldexp.c
+++ /dev/null
@@ -1,122 +0,0 @@
-/* @(#)s_scalbn.c 5.1 93/09/24 */
-/* @(#)fdlibm.h 5.1 93/09/24 */
-/*
- * ====================================================
- * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
- *
- * Developed at SunPro, a Sun Microsystems, Inc. business.
- * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice
- * is preserved.
- * ====================================================
- */
-
-#include <sys/cdefs.h>
-
-#include <sys/types.h>
-#include <endian.h>
-#include <math.h>
-
-/* Bit fiddling routines copied from msun/src/math_private.h,v 1.15 */
-
-#if BYTE_ORDER == BIG_ENDIAN
-
-typedef union
-{
- double value;
- struct
- {
- u_int32_t msw;
- u_int32_t lsw;
- } parts;
-} ieee_double_shape_type;
-
-#endif
-
-#if BYTE_ORDER == LITTLE_ENDIAN
-
-typedef union
-{
- double value;
- struct
- {
- u_int32_t lsw;
- u_int32_t msw;
- } parts;
-} ieee_double_shape_type;
-
-#endif
-
-/* Get two 32 bit ints from a double. */
-
-#define EXTRACT_WORDS(ix0,ix1,d) \
-do { \
- ieee_double_shape_type ew_u; \
- ew_u.value = (d); \
- (ix0) = ew_u.parts.msw; \
- (ix1) = ew_u.parts.lsw; \
-} while (0)
-
-/* Get the more significant 32 bit int from a double. */
-
-#define GET_HIGH_WORD(i,d) \
-do { \
- ieee_double_shape_type gh_u; \
- gh_u.value = (d); \
- (i) = gh_u.parts.msw; \
-} while (0)
-
-/* Set the more significant 32 bits of a double from an int. */
-
-#define SET_HIGH_WORD(d,v) \
-do { \
- ieee_double_shape_type sh_u; \
- sh_u.value = (d); \
- sh_u.parts.msw = (v); \
- (d) = sh_u.value; \
-} while (0)
-
-
-static const double
-two54 = 1.80143985094819840000e+16, /* 0x43500000, 0x00000000 */
-twom54 = 5.55111512312578270212e-17, /* 0x3C900000, 0x00000000 */
-huge = 1.0e+300,
-tiny = 1.0e-300;
-
-static double
-_copysign(double x, double y)
-{
- u_int32_t hx,hy;
- GET_HIGH_WORD(hx,x);
- GET_HIGH_WORD(hy,y);
- SET_HIGH_WORD(x,(hx&0x7fffffff)|(hy&0x80000000));
- return x;
-}
-
-double
-ldexp(double x, int n)
-{
- int32_t k,hx,lx;
- EXTRACT_WORDS(hx,lx,x);
- k = (hx&0x7ff00000)>>20; /* extract exponent */
- if (k==0) { /* 0 or subnormal x */
- if ((lx|(hx&0x7fffffff))==0) return x; /* +-0 */
- x *= two54;
- GET_HIGH_WORD(hx,x);
- k = ((hx&0x7ff00000)>>20) - 54;
- if (n< -50000) return tiny*x; /*underflow*/
- }
- if (k==0x7ff) return x+x; /* NaN or Inf */
- k = k+n;
- if (k > 0x7fe) return huge*_copysign(huge,x); /* overflow */
- if (k > 0) /* normal result */
- {SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20)); return x;}
- if (k <= -54) {
- if (n > 50000) /* in case integer overflow in n+k */
- return huge*_copysign(huge,x); /*overflow*/
- else return tiny*_copysign(tiny,x); /*underflow*/
- }
- k += 54; /* subnormal result */
- SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20));
- return x*twom54;
-}