diff --git a/src/lisp/s_scalbn.c b/src/lisp/s_scalbn.c index 329be8b8969b9b0effd4a48909f6621efaffc06b..4889385f940103d4eb0f96ff70648da115755ac3 100644 --- a/src/lisp/s_scalbn.c +++ b/src/lisp/s_scalbn.c @@ -31,33 +31,37 @@ huge = 1.0e+300, tiny = 1.0e-300; #ifdef __STDC__ - double scalbn (double x, int n) + double fdlibm_scalbn (double x, int n) #else - double scalbn (x,n) + double fdlibm_scalbn (x,n) double x; int n; #endif { int k,hx,lx; - hx = __HI(x); - lx = __LO(x); + union { int i[2]; double d; } ux; + + ux.d = x; + hx = ux.i[HIWORD]; + lx = ux.i[LOWORD]; k = (hx&0x7ff00000)>>20; /* extract exponent */ if (k==0) { /* 0 or subnormal x */ if ((lx|(hx&0x7fffffff))==0) return x; /* +-0 */ - x *= two54; - hx = __HI(x); + x *= two54; + ux.d = x; + hx = ux.i[HIWORD]; k = ((hx&0x7ff00000)>>20) - 54; - if (n< -50000) return tiny*x; /*underflow*/ + if (n< -50000) return fdlibm_setexception(x, FDLIBM_UNDERFLOW);; /*underflow*/ } if (k==0x7ff) return x+x; /* NaN or Inf */ k = k+n; - if (k > 0x7fe) return huge*copysign(huge,x); /* overflow */ + if (k > 0x7fe) return fdlibm_setexception(x, FDLIBM_OVERFLOW); /* overflow */ if (k > 0) /* normal result */ - {__HI(x) = (hx&0x800fffff)|(k<<20); return x;} + {ux.i[HIWORD] = (hx&0x800fffff)|(k<<20); return x;} if (k <= -54) if (n > 50000) /* in case integer overflow in n+k */ - return huge*copysign(huge,x); /*overflow*/ - else return tiny*copysign(tiny,x); /*underflow*/ + return fdlibm_setexception(x, FDLIBM_OVERFLOW); /*overflow*/ + else return fdlibm_setexception(x, FDLIBM_UNDERFLOW); /*underflow*/ k += 54; /* subnormal result */ - __HI(x) = (hx&0x800fffff)|(k<<20); + ux.i[HIWORD] = (hx&0x800fffff)|(k<<20); return x*twom54; }