47 lines
1.5 KiB
C
47 lines
1.5 KiB
C
/* go-cdiv.c -- complex division routines
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Copyright 2013 The Go Authors. All rights reserved.
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Use of this source code is governed by a BSD-style
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license that can be found in the LICENSE file. */
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/* Calls to these functions are generated by the Go frontend for
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division of complex64 or complex128. We use these because Go's
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complex division expects slightly different results from the GCC
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default. When dividing NaN+1.0i / 0+0i, Go expects NaN+NaNi but
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GCC generates NaN+Infi. NaN+Infi seems wrong seems the rules of
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C99 Annex G specify that if either side of a complex number is Inf,
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the the whole number is Inf, but an operation involving NaN ought
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to result in NaN, not Inf. */
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__complex float
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__go_complex64_div (__complex float a, __complex float b)
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{
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if (__builtin_expect (b == 0+0i, 0))
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{
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if (!__builtin_isinff (__real__ a)
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&& !__builtin_isinff (__imag__ a)
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&& (__builtin_isnanf (__real__ a) || __builtin_isnanf (__imag__ a)))
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{
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/* Pass "1" to nanf to match math/bits.go. */
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return __builtin_nanf("1") + __builtin_nanf("1")*1i;
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}
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}
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return a / b;
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}
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__complex double
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__go_complex128_div (__complex double a, __complex double b)
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{
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if (__builtin_expect (b == 0+0i, 0))
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{
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if (!__builtin_isinf (__real__ a)
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&& !__builtin_isinf (__imag__ a)
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&& (__builtin_isnan (__real__ a) || __builtin_isnan (__imag__ a)))
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{
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/* Pass "1" to nan to match math/bits.go. */
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return __builtin_nan("1") + __builtin_nan("1")*1i;
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}
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}
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return a / b;
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}
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