25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * CDDL HEADER START
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * The contents of this file are subject to the terms of the
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * Common Development and Distribution License (the "License").
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * You may not use this file except in compliance with the License.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * or http://www.opensolaris.org/os/licensing.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * See the License for the specific language governing permissions
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * and limitations under the License.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * When distributing Covered Code, include this CDDL HEADER in each
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
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25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * CDDL HEADER END
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * Use is subject to license terms.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis movl 12(%esp),%eax / eax <-- sign and bexp of x
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis testl $0x80000000,8(%esp) / test msb of hi_32(sgnfcnd(x))
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis jz .ilogbl_not_finite / jump if unsupported format
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis subl $16383,%eax / unbias exponent by 16383 = 0x3fff
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis movl $0x7fffffff,%eax / x is NaN/inf/unsup
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis movl 8(%esp),%eax / eax <-- hi_32(sgnfcnd(x))
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis jnz .ilogbl_subnorm / jump iff x is subnormal
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis movl $0x80000001,%eax / x is +/-0, so return 0x80000001
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis andl $_C99SUSv3_ilogb_0InfNaN_raises_invalid,%ecx
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis fdivp %st,%st(0) / raise invalid as per SUSv3
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis.ilogbl_subnorm: / subnormal or pseudo-denormal input
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis andl 8(%esp),%eax / eax <-- sign and bexp of x*2**63
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis subl $16445,%eax / unbias it by (16,383 + 63)