1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21/* 22 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 23 */ 24/* 25 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 26 * Use is subject to license terms. 27 */ 28 29 .file "log.s" 30 31#include "libm.h" 32LIBM_ANSI_PRAGMA_WEAK(log,function) 33#include "libm_synonyms.h" 34#include "libm_protos.h" 35 36 ENTRY(log) 37 fldln2 / loge(2) 38 movl 8(%esp),%eax / eax <-- hi_32(x) 39 testl $0x80000000,%eax 40 jnz .maybe_0_or_less 41 testl $0x7fffffff,%eax 42 jz .maybe_0 43 fldl 4(%esp) / arg, loge(2) 44 fyl2x / loge(2)*log2(arg); ln(arg) 45 ret 46 47.maybe_0: 48 movl 4(%esp),%ecx / ecx <-- lo_32(x) 49 cmpl $0,%ecx 50 je .zero / no branch if x is +denormal 51.neg_nan_reentry: 52 fldl 4(%esp) / arg, loge(2) 53 fyl2x / loge(2)*log2(arg); ln(arg) 54 ret 55 56.zero_or_less: 57 / x =< 0 58 testl $0x7fffffff,%eax 59 jnz .less_than_0 60 movl 4(%esp),%ecx / ecx <-- lo_32(x) 61 cmpl $0,%ecx 62 jne .less_than_0 / branch if x is -denormal 63.zero: 64 / x = +/-0 65 pushl %ebp 66 movl %esp,%ebp 67 PIC_SETUP(1) 68 pushl $16 69 jmp .merge 70 71.maybe_0_or_less: 72 cmpl $0xfff00000,%eax / -INF below hi_32(x)? 73 ja .neg_nan_reentry 74 jb .zero_or_less 75 movl 4(%esp),%ecx / ecx <-- lo_32(x) 76 cmpl $0,%ecx / is x NaN or -INF? 77 jne .neg_nan_reentry / branch if x is NaN with signbit = 1 78 / x = -INF 79.less_than_0: 80 pushl %ebp 81 movl %esp,%ebp 82 PIC_SETUP(2) 83 pushl $17 84.merge: 85 fstp %st(0) / stack empty 86 pushl 12(%ebp) 87 pushl 8(%ebp) 88 pushl 12(%ebp) 89 pushl 8(%ebp) 90 call PIC_F(_SVID_libm_err) 91 addl $20,%esp 92 PIC_WRAPUP 93 leave 94 ret 95 .align 4 96 SET_SIZE(log) 97