ac465d29b4
I'm taking a page from Dolphin's book, and including copies of each dependency's source code. This combines the ease of use of including pre-built libraries instead of needing to navigate a package manager - as is (or was) the case for MSVC - with the portability of using packages. Granted, this method's more of a jack of all trades, master of none, since it's *less* user-friendly than prebuilt packages (compilation times), and you don't get the per-distro compatibility fixes you'd get from a package manager. You can still use system libs if you want. In fact, it's still the default behaviour: compiling the libs manually is just a fallback. I'll add an option to force-enable this soon, however, since it's a nicer way to produce static MSYS2 builds than the hackish nightmare that I was using before. Not to mention, having my own copy of the sources means I can provide my own fixes and tweaks your package manager may not. For example, I can combine MSYS2's FreeType subpixel rendering with vcpkg's fix for SDL2 exporting its symbols in static builds.
69 lines
1.8 KiB
C
69 lines
1.8 KiB
C
/*
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* ====================================================
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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*
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* Developed at SunPro, a Sun Microsystems, Inc. business.
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* Permission to use, copy, modify, and distribute this
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* software is freely granted, provided that this notice
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* is preserved.
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* ====================================================
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*/
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/*
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* scalbln(double x, long n)
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* scalbln(x,n) returns x * 2**n computed by exponent
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* manipulation rather than by actually performing an
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* exponentiation or a multiplication.
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*/
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#include "math_libm.h"
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#include "math_private.h"
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#include <limits.h>
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static const double
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two54 = 1.80143985094819840000e+16, /* 0x43500000, 0x00000000 */
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twom54 = 5.55111512312578270212e-17, /* 0x3C900000, 0x00000000 */
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huge = 1.0e+300,
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tiny = 1.0e-300;
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double scalbln(double x, long n)
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{
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int32_t k, hx, lx;
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EXTRACT_WORDS(hx, lx, x);
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k = (hx & 0x7ff00000) >> 20; /* extract exponent */
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if (k == 0) { /* 0 or subnormal x */
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if ((lx | (hx & 0x7fffffff)) == 0)
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return x; /* +-0 */
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x *= two54;
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GET_HIGH_WORD(hx, x);
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k = ((hx & 0x7ff00000) >> 20) - 54;
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}
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if (k == 0x7ff)
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return x + x; /* NaN or Inf */
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k = k + n;
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if (k > 0x7fe)
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return huge * copysign(huge, x); /* overflow */
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if (n < -50000)
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return tiny * copysign(tiny, x); /* underflow */
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if (k > 0) { /* normal result */
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SET_HIGH_WORD(x, (hx & 0x800fffff) | (k << 20));
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return x;
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}
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if (k <= -54) {
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if (n > 50000) /* in case integer overflow in n+k */
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return huge * copysign(huge, x); /* overflow */
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return tiny * copysign(tiny, x); /* underflow */
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}
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k += 54; /* subnormal result */
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SET_HIGH_WORD(x, (hx & 0x800fffff) | (k << 20));
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return x * twom54;
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}
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libm_hidden_def(scalbln)
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double scalbn(double x, int n)
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{
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return scalbln(x, n);
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}
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libm_hidden_def(scalbn)
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