projects / apple / libc.git / blame
| Commit | Line | Data |
|---|---|---|
| 3d9156a7 A |
1 | /* |
| 2 | * Copyright (c) 2004 Apple Computer, Inc. All rights reserved. | |
| 3 | * | |
| 4 | * @APPLE_LICENSE_HEADER_START@ | |
| 5 | * | |
| 6 | * This file contains Original Code and/or Modifications of Original Code | |
| 7 | * as defined in and that are subject to the Apple Public Source License | |
| 8 | * Version 2.0 (the 'License'). You may not use this file except in | |
| 9 | * compliance with the License. Please obtain a copy of the License at | |
| 10 | * http:www.opensource.apple.com/apsl/ and read it before using this | |
| 11 | * file. | |
| 12 | * | |
| 13 | * The Original Code and all software distributed under the License are | |
| 14 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER | |
| 15 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, | |
| 16 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, | |
| 17 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. | |
| 18 | * Please see the License for the specific language governing rights and | |
| 19 | * limitations under the License. | |
| 20 | * | |
| 21 | * @APPLE_LICENSE_HEADER_END@ | |
| 22 | */ | |
| 23 | ||
| 24 | #include <sys/cdefs.h> | |
| 25 | #include <stdint.h> | |
| 26 | #include <strings.h> | |
| 27 | #include <float.h> | |
| 28 | #include <math.h> | |
| 29 | #include <alloca.h> | |
| 30 | ||
| 31 | #include "fpmath.h" | |
| 32 | ||
| 33 | #define BITS64 64 | |
| 34 | #define DBL_BIAS (DBL_MAX_EXP - 1) | |
| 35 | #define DBL_SUBEXP (-DBL_BIAS + 1) | |
| 36 | #define LL_BITS (8 * sizeof(int64_t)) | |
| 37 | #define LL_HIGHBIT (1LL << 63) | |
| 38 | ||
| 39 | __private_extern__ void | |
| 40 | _ldbl2array32dd(union IEEEl2bits u, uint32_t *a) | |
| 41 | { | |
| 42 | int bit, shift, highbit; | |
| 43 | uint64_t a64[2]; | |
| 44 | int64_t t64; | |
| 45 | ||
| 46 | bzero(a64, 2 * sizeof(*a64)); | |
| 47 | ||
| 48 | switch (__fpclassifyd(u.d[0])) { | |
| 49 | case FP_NORMAL: | |
| 50 | a64[1] = (1LL << (LDBL_MANT_DIG - BITS64 - 1)); | |
| 51 | /* drop through */ | |
| 52 | case FP_SUBNORMAL: | |
| 53 | a64[1] |= ((uint64_t)u.bits.manh >> (BITS64 - LDBL_MANL_SIZE)); | |
| 54 | a64[0] = ((uint64_t)u.bits.manh << LDBL_MANL_SIZE); | |
| 55 | break; | |
| 56 | default: | |
| 57 | goto done; | |
| 58 | } | |
| 59 | ||
| 60 | switch (__fpclassifyd(u.d[1])) { | |
| 61 | case FP_NORMAL: | |
| 62 | bit = LDBL_MANT_DIG - (int)u.bits.exp + (int)u.bits.exp2 - 1; | |
| 63 | t64 = (1LL << bit); | |
| 64 | break; | |
| 65 | case FP_SUBNORMAL: | |
| 66 | bit = LDBL_MANT_DIG - (int)u.bits.exp; | |
| 67 | t64 = 0; | |
| 68 | break; | |
| 69 | default: | |
| 70 | goto done; | |
| 71 | } | |
| 72 | shift = LDBL_MANL_SIZE - bit - 1; | |
| 73 | if (shift >= 0) | |
| 74 | t64 |= (u.bits.manl >> shift); | |
| 75 | else | |
| 76 | t64 |= (u.bits.manl << (-shift)); | |
| 77 | highbit = ((a64[0] & LL_HIGHBIT) != 0); | |
| 78 | if (u.bits.sign == u.bits.sign2) { | |
| 79 | a64[0] += t64; | |
| 80 | if (highbit && !(a64[0] & LL_HIGHBIT)) /* carry */ | |
| 81 | a64[1]++; | |
| 82 | } else { | |
| 83 | a64[0] -= t64; | |
| 84 | if (!highbit && (a64[0] & LL_HIGHBIT)) /* borrow */ | |
| 85 | a64[1]--; | |
| 86 | } | |
| 87 | ||
| 88 | done: | |
| 89 | a[0] = (uint32_t)a64[0]; | |
| 90 | a[1] = (uint32_t)(a64[0] >> 32); | |
| 91 | a[2] = (uint32_t)a64[1]; | |
| 92 | a[3] = (uint32_t)(a64[1] >> 32); | |
| 93 | } |