125c28e83SPiotr Jasiukajtis/* 225c28e83SPiotr Jasiukajtis * CDDL HEADER START 325c28e83SPiotr Jasiukajtis * 425c28e83SPiotr Jasiukajtis * The contents of this file are subject to the terms of the 525c28e83SPiotr Jasiukajtis * Common Development and Distribution License (the "License"). 625c28e83SPiotr Jasiukajtis * You may not use this file except in compliance with the License. 725c28e83SPiotr Jasiukajtis * 825c28e83SPiotr Jasiukajtis * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 925c28e83SPiotr Jasiukajtis * or http://www.opensolaris.org/os/licensing. 1025c28e83SPiotr Jasiukajtis * See the License for the specific language governing permissions 1125c28e83SPiotr Jasiukajtis * and limitations under the License. 1225c28e83SPiotr Jasiukajtis * 1325c28e83SPiotr Jasiukajtis * When distributing Covered Code, include this CDDL HEADER in each 1425c28e83SPiotr Jasiukajtis * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 1525c28e83SPiotr Jasiukajtis * If applicable, add the following below this CDDL HEADER, with the 1625c28e83SPiotr Jasiukajtis * fields enclosed by brackets "[]" replaced with your own identifying 1725c28e83SPiotr Jasiukajtis * information: Portions Copyright [yyyy] [name of copyright owner] 1825c28e83SPiotr Jasiukajtis * 1925c28e83SPiotr Jasiukajtis * CDDL HEADER END 2025c28e83SPiotr Jasiukajtis */ 2125c28e83SPiotr Jasiukajtis/* 2225c28e83SPiotr Jasiukajtis * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 2325c28e83SPiotr Jasiukajtis */ 2425c28e83SPiotr Jasiukajtis/* 2525c28e83SPiotr Jasiukajtis * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 2625c28e83SPiotr Jasiukajtis * Use is subject to license terms. 2725c28e83SPiotr Jasiukajtis */ 2825c28e83SPiotr Jasiukajtis 2925c28e83SPiotr Jasiukajtis .file "expl.s" 3025c28e83SPiotr Jasiukajtis 3125c28e83SPiotr Jasiukajtis#include "libm.h" 3225c28e83SPiotr JasiukajtisLIBM_ANSI_PRAGMA_WEAK(expl,function) 3325c28e83SPiotr Jasiukajtis 3425c28e83SPiotr Jasiukajtis .data 3525c28e83SPiotr Jasiukajtis .align 16 3625c28e83SPiotr Jasiukajtisln2_hi: .4byte 0xd1d00000, 0xb17217f7, 0x3ffe, 0x0 3725c28e83SPiotr Jasiukajtisln2_lo: .4byte 0x4c67fc0d, 0x8654361c, 0xbfce, 0x0 3825c28e83SPiotr Jasiukajtis 3925c28e83SPiotr Jasiukajtis ENTRY(expl) 4025c28e83SPiotr Jasiukajtis movl 16(%rsp),%ecx / cx <--sign&bexp(x) 4125c28e83SPiotr Jasiukajtis andl $0x7fff,%ecx / ecx <-- zero_xtnd(bexp(x)) 4225c28e83SPiotr Jasiukajtis cmpl $0x3ffe,%ecx / Is |x| < 0.5? 4325c28e83SPiotr Jasiukajtis jb 2f / If so, see which shortcut to take 4425c28e83SPiotr Jasiukajtis je .check_tail / More checking if 0.5 <= |x| < 1 4525c28e83SPiotr Jasiukajtis.general_case: / Here, |x| >= 1 or x is NaN 4625c28e83SPiotr Jasiukajtis cmpl $0x7fff,%ecx / bexp(|x|) = bexp(INF)? 4725c28e83SPiotr Jasiukajtis je .not_finite / if so, x is not finite 4825c28e83SPiotr Jasiukajtis cmpl $0x400e,%ecx / |x| < 32768 = 2^15? 4925c28e83SPiotr Jasiukajtis jb .finite_non_special / if so, proceed with argument reduction 5025c28e83SPiotr Jasiukajtis fldt 8(%rsp) / x 5125c28e83SPiotr Jasiukajtis fld1 / 1, x 5225c28e83SPiotr Jasiukajtis jmp 1f 5325c28e83SPiotr Jasiukajtis.finite_non_special: / Here, ln(2) < |x| < 2^15 5425c28e83SPiotr Jasiukajtis fldt 8(%rsp) / x 5525c28e83SPiotr Jasiukajtis fld %st(0) / x, x 5625c28e83SPiotr Jasiukajtis fldl2e / log2(e), x, x 5725c28e83SPiotr Jasiukajtis fmulp / z := x*log2(e), x 5825c28e83SPiotr Jasiukajtis frndint / [z], x 5925c28e83SPiotr Jasiukajtis fst %st(2) / [z], x, [z] 6025c28e83SPiotr Jasiukajtis PIC_SETUP(1) 6125c28e83SPiotr Jasiukajtis fldt PIC_L(ln2_hi) / ln2_hi, [z], x, [z] 6225c28e83SPiotr Jasiukajtis fmulp / [z]*ln2_hi, x, [z] 6325c28e83SPiotr Jasiukajtis fsubrp %st,%st(1) / x-[z]*ln2_hi, [z] 6425c28e83SPiotr Jasiukajtis fldt PIC_L(ln2_lo) / ln2_lo, x-[z]*ln2_hi, [z] 6525c28e83SPiotr Jasiukajtis PIC_WRAPUP 6625c28e83SPiotr Jasiukajtis fmul %st(2),%st / [z]*ln2_lo, x-[z]*ln2_hi, [z] 6725c28e83SPiotr Jasiukajtis fsubrp %st,%st(1) / r := x-[z]*ln(2), [z] 6825c28e83SPiotr Jasiukajtis fldl2e / log2(e), r, [z] 6925c28e83SPiotr Jasiukajtis fmulp / f := r*log2(e), [z] 7025c28e83SPiotr Jasiukajtis f2xm1 / 2^f-1,[z] 7125c28e83SPiotr Jasiukajtis fld1 / 1, 2^f-1, [z] 7225c28e83SPiotr Jasiukajtis faddp %st,%st(1) / 2^f, [z] 7325c28e83SPiotr Jasiukajtis1: 7425c28e83SPiotr Jasiukajtis fscale / e^x, [z] 7525c28e83SPiotr Jasiukajtis fstp %st(1) 7625c28e83SPiotr Jasiukajtis ret 7725c28e83SPiotr Jasiukajtis 7825c28e83SPiotr Jasiukajtis2: / Here, |x| < 0.5 7925c28e83SPiotr Jasiukajtis cmpl $0x3fbe,%ecx / Is |x| >= 2^-65? 8025c28e83SPiotr Jasiukajtis jae .shortcut / If so, take a shortcut 8125c28e83SPiotr Jasiukajtis fldt 8(%rsp) / x 8225c28e83SPiotr Jasiukajtis fld1 / 1, x 8325c28e83SPiotr Jasiukajtis faddp %st,%st(1) / 1+x (for inexact & directed rounding) 8425c28e83SPiotr Jasiukajtis ret 8525c28e83SPiotr Jasiukajtis 8625c28e83SPiotr Jasiukajtis.check_tail: 8725c28e83SPiotr Jasiukajtis movl 12(%rsp),%ecx / ecx <-- hi_32(sgnfcnd(x)) 8825c28e83SPiotr Jasiukajtis cmpl $0xb17217f7,%ecx / Is |x| < ln(2)? 8925c28e83SPiotr Jasiukajtis ja .finite_non_special 9025c28e83SPiotr Jasiukajtis jb .shortcut 9125c28e83SPiotr Jasiukajtis movl 8(%rsp),%edx / edx <-- lo_32(x) 9225c28e83SPiotr Jasiukajtis cmpl $0xd1cf79ab,%edx / Is |x| slightly < ln(2)? 9325c28e83SPiotr Jasiukajtis ja .finite_non_special / branch if |x| slightly > ln(2) 9425c28e83SPiotr Jasiukajtis.shortcut: 9525c28e83SPiotr Jasiukajtis / Here, |x| < ln(2), so |z| = |x/ln(2)| < 1, 9625c28e83SPiotr Jasiukajtis / whence z is in f2xm1's domain. 9725c28e83SPiotr Jasiukajtis fldt 8(%rsp) / x 9825c28e83SPiotr Jasiukajtis fldl2e / log2(e), x 9925c28e83SPiotr Jasiukajtis fmulp / x*log2(e) 10025c28e83SPiotr Jasiukajtis f2xm1 / 2^(x*log2(e))-1 = e^x-1 10125c28e83SPiotr Jasiukajtis fld1 / 1, e^x-1 10225c28e83SPiotr Jasiukajtis faddp %st,%st(1) / e^x 10325c28e83SPiotr Jasiukajtis ret 10425c28e83SPiotr Jasiukajtis 10525c28e83SPiotr Jasiukajtis.not_finite: 10625c28e83SPiotr Jasiukajtis movl 12(%rsp),%ecx / ecx <-- hi_32(sgnfcnd(x)) 10725c28e83SPiotr Jasiukajtis cmpl $0x80000000,%ecx / hi_32(|x|) = hi_32(INF)? 10825c28e83SPiotr Jasiukajtis jne .NaN_or_pinf / if not, x is NaN 10925c28e83SPiotr Jasiukajtis movl 8(%rsp),%edx / edx <-- lo_32(x) 11025c28e83SPiotr Jasiukajtis cmpl $0,%edx / lo_32(x) = 0? 11125c28e83SPiotr Jasiukajtis jne .NaN_or_pinf / if not, x is NaN 11225c28e83SPiotr Jasiukajtis movl 16(%rsp),%eax / ax <-- sign&bexp((x)) 11325c28e83SPiotr Jasiukajtis andl $0x8000,%eax / here, x is infinite, but +/-? 11425c28e83SPiotr Jasiukajtis jz .NaN_or_pinf / branch if x = +INF 11525c28e83SPiotr Jasiukajtis fldz / Here, x = -inf, so return 0 11625c28e83SPiotr Jasiukajtis ret 11725c28e83SPiotr Jasiukajtis 11825c28e83SPiotr Jasiukajtis.NaN_or_pinf: 11925c28e83SPiotr Jasiukajtis / Here, x = NaN or +inf, so load x and return immediately. 12025c28e83SPiotr Jasiukajtis fldt 8(%rsp) 12125c28e83SPiotr Jasiukajtis fadd %st(0),%st / quiet SNaN 12225c28e83SPiotr Jasiukajtis ret 12325c28e83SPiotr Jasiukajtis .align 16 12425c28e83SPiotr Jasiukajtis SET_SIZE(expl) 125