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@@ -11,7 +11,7 @@
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* scalbn (double x, int n)
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- * scalbn(x,n) returns x* 2**n computed by exponent
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+ * scalbn(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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@@ -20,35 +20,57 @@
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#include "math_private.h"
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static const double
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-two54 = 1.80143985094819840000e+16,
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-twom54 = 5.55111512312578270212e-17,
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+two54 = 1.80143985094819840000e+16,
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+twom54 = 5.55111512312578270212e-17,
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huge = 1.0e+300,
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tiny = 1.0e-300;
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double scalbn(double x, int 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;
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- if (k==0) {
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- if ((lx|(hx&0x7fffffff))==0) return x;
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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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- if (n< -50000) return tiny*x;
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- }
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- if (k==0x7ff) return x+x;
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- k = k+n;
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- if (k > 0x7fe) return huge*copysign(huge,x);
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- if (k > 0)
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- {SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20)); return x;}
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- if (k <= -54) {
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- if (n > 50000)
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- return huge*copysign(huge,x);
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- else return tiny*copysign(tiny,x);
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+ int32_t k, hx, lx;
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+
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+ EXTRACT_WORDS(hx, lx, x);
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+ k = (hx & 0x7ff00000) >> 20;
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+ if (k == 0) {
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+ if ((lx | (hx & 0x7fffffff)) == 0)
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+ return x;
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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;
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+ k = k + n;
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+ if (k > 0x7fe)
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+ return huge * copysign(huge, x);
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+ if (n < -50000)
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+ return tiny * copysign(tiny, x);
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+ if (k > 0) {
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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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- k += 54;
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- SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20));
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- return x*twom54;
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+ if (k <= -54) {
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+ if (n > 50000)
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+ return huge * copysign(huge, x);
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+ return tiny * copysign(tiny, x);
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+ }
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+ k += 54;
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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(scalbn)
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+
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+#if LONG_MAX == INT_MAX
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+
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+ * because it tries to declare "typeof(scalbn) scalbln;"
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+ * which tries to give "int" parameter to scalbln.
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+ * Doing it by hand:
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+ */
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+__typeof(scalbln) scalbln __attribute__((alias("scalbn")));
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+#else
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+double scalbln(double x, long n)
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+{
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+ return scalbn(x, n);
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+}
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+#endif
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+libm_hidden_def(scalbln)
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