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_protos.h" 34 35 ENTRY(log) 36 fldln2 / loge(2) 37 movl 8(%esp),%eax / eax <-- hi_32(x) 38 testl $0x80000000,%eax 39 jnz .maybe_0_or_less 40 testl $0x7fffffff,%eax 41 jz .maybe_0 42 fldl 4(%esp) / arg, loge(2) 43 fyl2x / loge(2)*log2(arg); ln(arg) 44 ret 45 46.maybe_0: 47 movl 4(%esp),%ecx / ecx <-- lo_32(x) 48 cmpl $0,%ecx 49 je .zero / no branch if x is +denormal 50.neg_nan_reentry: 51 fldl 4(%esp) / arg, loge(2) 52 fyl2x / loge(2)*log2(arg); ln(arg) 53 ret 54 55.zero_or_less: 56 / x =< 0 57 testl $0x7fffffff,%eax 58 jnz .less_than_0 59 movl 4(%esp),%ecx / ecx <-- lo_32(x) 60 cmpl $0,%ecx 61 jne .less_than_0 / branch if x is -denormal 62.zero: 63 / x = +/-0 64 pushl %ebp 65 movl %esp,%ebp 66 PIC_SETUP(1) 67 pushl $16 68 jmp .merge 69 70.maybe_0_or_less: 71 cmpl $0xfff00000,%eax / -INF below hi_32(x)? 72 ja .neg_nan_reentry 73 jb .zero_or_less 74 movl 4(%esp),%ecx / ecx <-- lo_32(x) 75 cmpl $0,%ecx / is x NaN or -INF? 76 jne .neg_nan_reentry / branch if x is NaN with signbit = 1 77 / x = -INF 78.less_than_0: 79 pushl %ebp 80 movl %esp,%ebp 81 PIC_SETUP(2) 82 pushl $17 83.merge: 84 fstp %st(0) / stack empty 85 pushl 12(%ebp) 86 pushl 8(%ebp) 87 pushl 12(%ebp) 88 pushl 8(%ebp) 89 call PIC_F(_SVID_libm_err) 90 addl $20,%esp 91 PIC_WRAPUP 92 leave 93 ret 94 .align 4 95 SET_SIZE(log) 96