/* * Written by J.T. Conklin . * Public domain. * * $NetBSD: e_expf.S,v 1.5 2003/07/26 19:24:58 salo Exp $ * $DragonFly: src/lib/libm/arch/i386/e_expf.S,v 1.1 2005/07/26 21:15:19 joerg Exp $ */ #include #include "abi.h" /* e^x = 2^(x * log2(e)) */ ENTRY(expf) XMM_ONE_ARG_FLOAT_PROLOGUE flds ARG_FLOAT_ONE fldl2e fmulp /* x * log2(e) */ fld %st(0) frndint /* int(x * log2(e)) */ fsubr %st(0),%st(1) /* fract(x * log2(e)) */ fxch f2xm1 /* 2^(fract(x * log2(e))) - 1 */ fld1 faddp /* 2^(fract(x * log2(e))) */ fscale /* e^x */ fstp %st(1) XMM_FLOAT_EPILOGUE ret