1 /* origin: FreeBSD /usr/src/lib/msun/src/ld80/invtrig.h */
3 * Copyright (c) 2008 David Schultz <das@FreeBSD.ORG>
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30 #if LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
32 #define BIAS (LDBL_MAX_EXP - 1)
33 #define MANH_SIZE LDBL_MANH_SIZE
35 /* Approximation thresholds. */
36 #define ASIN_LINEAR (BIAS - 32) /* 2**-32 */
37 #define ACOS_CONST (BIAS - 65) /* 2**-65 */
38 #define ATAN_CONST (BIAS + 65) /* 2**65 */
39 #define ATAN_LINEAR (BIAS - 32) /* 2**-32 */
42 #define THRESH ((0xe666666666666666ULL>>(64-(MANH_SIZE-1)))|LDBL_NBIT)
44 /* Constants shared by the long double inverse trig functions. */
57 #define atanhi __atanhi
58 #define atanlo __atanlo
62 #define pio2_hi atanhi[3]
63 #define pio2_lo atanlo[3]
64 #define pio4_hi atanhi[1]
67 typedef struct longdouble {
72 typedef long double LONGDOUBLE;
75 extern const LONGDOUBLE pS0, pS1, pS2, pS3, pS4, pS5, pS6;
76 extern const LONGDOUBLE qS1, qS2, qS3, qS4, qS5;
77 extern const LONGDOUBLE atanhi[], atanlo[], aT[];
78 extern const LONGDOUBLE pi_lo;
81 static inline long double
84 return (x * (pS0 + x * (pS1 + x * (pS2 + x * (pS3 + x * \
85 (pS4 + x * (pS5 + x * pS6)))))));
88 static inline long double
91 return (1.0 + x * (qS1 + x * (qS2 + x * (qS3 + x * (qS4 + x * qS5)))));
94 static inline long double
97 return (aT[0] + x * (aT[2] + x * (aT[4] + x * (aT[6] + x * \
98 (aT[8] + x * (aT[10] + x * aT[12]))))));
101 static inline long double
104 return (aT[1] + x * (aT[3] + x * (aT[5] + x * (aT[7] + x * \
105 (aT[9] + x * aT[11])))));