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typedef unsigned int u_int32_t;
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typedef unsigned int u_int32_t;
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typedef signed int int32_t;
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typedef signed int int32_t;
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// Big endian struct...
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// Big endian struct...
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typedef union
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typedef union {
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{
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double value;
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double value;
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struct
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struct {
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{
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u_int32_t msw;
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u_int32_t msw;
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u_int32_t lsw;
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u_int32_t lsw;
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} parts;
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} parts;
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} ieee_double_shape_type;
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} ieee_double_shape_type;
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/*
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/*
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typedef union
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typedef union
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{
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{
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double value;
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double value;
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struct
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struct
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{
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{
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u_int32_t lsw;
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u_int32_t lsw;
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u_int32_t msw;
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u_int32_t msw;
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} parts;
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} parts;
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} ieee_double_shape_type;
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} ieee_double_shape_type;
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*/
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*/
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/* Get two 32 bit ints from a double. */
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/* Get two 32 bit ints from a double. */
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#define EXTRACT_WORDS(ix0,ix1,d) \
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#define EXTRACT_WORDS(ix0,ix1,d) \
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do { \
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do { \
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ieee_double_shape_type ew_u; \
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ieee_double_shape_type ew_u; \
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ew_u.value = (d); \
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ew_u.value = (d); \
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(ix0) = ew_u.parts.msw; \
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(ix0) = ew_u.parts.msw; \
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(ix1) = ew_u.parts.lsw; \
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(ix1) = ew_u.parts.lsw; \
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} while (0)
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} while (0)
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/* Get the more significant 32 bit int from a double. */
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/* Get the more significant 32 bit int from a double. */
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#define GET_HIGH_WORD(i,d) \
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#define GET_HIGH_WORD(i,d) \
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do { \
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do { \
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ieee_double_shape_type gh_u; \
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ieee_double_shape_type gh_u; \
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gh_u.value = (d); \
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gh_u.value = (d); \
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(i) = gh_u.parts.msw; \
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(i) = gh_u.parts.msw; \
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} while (0)
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} while (0)
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/* Get the less significant 32 bit int from a double. */
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/* Get the less significant 32 bit int from a double. */
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#define GET_LOW_WORD(i,d) \
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#define GET_LOW_WORD(i,d) \
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do { \
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do { \
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ieee_double_shape_type gl_u; \
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ieee_double_shape_type gl_u; \
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gl_u.value = (d); \
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gl_u.value = (d); \
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(i) = gl_u.parts.lsw; \
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(i) = gl_u.parts.lsw; \
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} while (0)
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} while (0)
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/* Set a double from two 32 bit ints. */
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/* Set a double from two 32 bit ints. */
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#define INSERT_WORDS(d,ix0,ix1) \
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#define INSERT_WORDS(d,ix0,ix1) \
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do { \
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do { \
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ieee_double_shape_type iw_u; \
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ieee_double_shape_type iw_u; \
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iw_u.parts.msw = (ix0); \
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iw_u.parts.msw = (ix0); \
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iw_u.parts.lsw = (ix1); \
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iw_u.parts.lsw = (ix1); \
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(d) = iw_u.value; \
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(d) = iw_u.value; \
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} while (0)
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} while (0)
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/* Set the more significant 32 bits of a double from an int. */
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/* Set the more significant 32 bits of a double from an int. */
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#define SET_HIGH_WORD(d,v) \
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#define SET_HIGH_WORD(d,v) \
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do { \
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do { \
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ieee_double_shape_type sh_u; \
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ieee_double_shape_type sh_u; \
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sh_u.value = (d); \
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sh_u.value = (d); \
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sh_u.parts.msw = (v); \
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sh_u.parts.msw = (v); \
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(d) = sh_u.value; \
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(d) = sh_u.value; \
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} while (0)
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} while (0)
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/* Set the less significant 32 bits of a double from an int. */
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/* Set the less significant 32 bits of a double from an int. */
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#define SET_LOW_WORD(d,v) \
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#define SET_LOW_WORD(d,v) \
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do { \
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do { \
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ieee_double_shape_type sl_u; \
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ieee_double_shape_type sl_u; \
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sl_u.value = (d); \
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sl_u.value = (d); \
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sl_u.parts.lsw = (v); \
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sl_u.parts.lsw = (v); \
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(d) = sl_u.value; \
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(d) = sl_u.value; \
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} while (0)
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} while (0)
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/* A union which permits us to convert between a float and a 32 bit
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/* A union which permits us to convert between a float and a 32 bit
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int. */
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int. */
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typedef union
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typedef union {
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{
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float value;
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float value;
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u_int32_t word;
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u_int32_t word;
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} ieee_float_shape_type;
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} ieee_float_shape_type;
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/* Get a 32 bit int from a float. */
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/* Get a 32 bit int from a float. */
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#define GET_FLOAT_WORD(i,d) \
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#define GET_FLOAT_WORD(i,d) \
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do { \
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do { \
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ieee_float_shape_type gf_u; \
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ieee_float_shape_type gf_u; \
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gf_u.value = (d); \
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gf_u.value = (d); \
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(i) = gf_u.word; \
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(i) = gf_u.word; \
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} while (0)
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} while (0)
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/* Set a float from a 32 bit int. */
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/* Set a float from a 32 bit int. */
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#define SET_FLOAT_WORD(d,i) \
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#define SET_FLOAT_WORD(d,i) \
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do { \
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do { \
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ieee_float_shape_type sf_u; \
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ieee_float_shape_type sf_u; \
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sf_u.word = (i); \
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sf_u.word = (i); \
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(d) = sf_u.value; \
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(d) = sf_u.value; \
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} while (0)
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} while (0)
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static const double one = 1.0;
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static const double one = 1.0;
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double modf(double x, double *iptr)
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double modf(double x, double *iptr)
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{
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{
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int32_t i0,i1,j0;
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int32_t i0, i1, j0;
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u_int32_t i;
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u_int32_t i;
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EXTRACT_WORDS(i0,i1,x);
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EXTRACT_WORDS(i0, i1, x);
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j0 = ((i0>>20)&0x7ff)-0x3ff; /* exponent of x */
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j0 = ((i0 >> 20) & 0x7ff) - 0x3ff; /* exponent of x */
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if(j0<20) { /* integer part in high x */
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if (j0 < 20) { /* integer part in high x */
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if(j0<0) { /* |x|<1 */
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if (j0 < 0) { /* |x|<1 */
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INSERT_WORDS(*iptr,i0&0x80000000,0); /* *iptr = +-0 */
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INSERT_WORDS(*iptr, i0 & 0x80000000, 0); /* *iptr = +-0 */
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return x;
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return x;
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} else {
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} else {
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i = (0x000fffff)>>j0;
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i = (0x000fffff) >> j0;
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if(((i0&i)|i1)==0) { /* x is integral */
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if (((i0 & i) | i1) == 0) { /* x is integral */
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u_int32_t high;
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u_int32_t high;
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*iptr = x;
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*iptr = x;
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GET_HIGH_WORD(high,x);
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GET_HIGH_WORD(high, x);
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INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */
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INSERT_WORDS(x, high & 0x80000000, 0); /* return +-0 */
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return x;
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return x;
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} else {
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} else {
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INSERT_WORDS(*iptr,i0&(~i),0);
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INSERT_WORDS(*iptr, i0 & (~i), 0);
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return x - *iptr;
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return x - *iptr;
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}
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}
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}
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}
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} else if (j0>51) { /* no fraction part */
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} else if (j0 > 51) { /* no fraction part */
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u_int32_t high;
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u_int32_t high;
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*iptr = x*one;
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*iptr = x * one;
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GET_HIGH_WORD(high,x);
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GET_HIGH_WORD(high, x);
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INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */
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INSERT_WORDS(x, high & 0x80000000, 0); /* return +-0 */
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return x;
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return x;
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} else { /* fraction part in low x */
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} else { /* fraction part in low x */
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i = ((u_int32_t)(0xffffffff))>>(j0-20);
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i = ((u_int32_t) (0xffffffff)) >> (j0 - 20);
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if((i1&i)==0) { /* x is integral */
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if ((i1 & i) == 0) { /* x is integral */
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u_int32_t high;
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u_int32_t high;
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*iptr = x;
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*iptr = x;
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GET_HIGH_WORD(high,x);
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GET_HIGH_WORD(high, x);
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INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */
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INSERT_WORDS(x, high & 0x80000000, 0); /* return +-0 */
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return x;
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return x;
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} else {
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} else {
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INSERT_WORDS(*iptr,i0,i1&(~i));
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INSERT_WORDS(*iptr, i0, i1 & (~i));
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return x - *iptr;
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return x - *iptr;
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}
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}
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}
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}
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}
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}
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