| The Android Open Source Project | 1dc9e47 | 2009-03-03 19:28:35 -0800 | [diff] [blame] | 1 | /*- |
| 2 | * Copyright (c) 2005 David Schultz <das@FreeBSD.ORG> |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * |
| 14 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
| 15 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 16 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 17 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| 18 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 19 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 20 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 21 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 22 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 23 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 24 | * SUCH DAMAGE. |
| 25 | */ |
| 26 | |
| 27 | /* |
| 28 | * Based on public-domain remainder routine by J.T. Conklin <jtc@NetBSD.org>. |
| 29 | */ |
| 30 | |
| 31 | #include <machine/asm.h> |
| 32 | __FBSDID("$FreeBSD: src/lib/msun/amd64/s_remquof.S,v 1.1 2005/03/25 04:40:44 das Exp $"); |
| 33 | |
| 34 | ENTRY(remquof) |
| 35 | movss %xmm0,-4(%rsp) |
| 36 | movss %xmm1,-8(%rsp) |
| 37 | flds -8(%rsp) |
| 38 | flds -4(%rsp) |
| 39 | 1: fprem1 |
| 40 | fstsw %ax |
| 41 | btw $10,%ax |
| 42 | jc 1b |
| 43 | fstp %st(1) |
| 44 | /* Extract the three low-order bits of the quotient from C0,C3,C1. */ |
| 45 | shrl $6,%eax |
| 46 | movl %eax,%ecx |
| 47 | andl $0x108,%eax |
| 48 | rorl $7,%eax |
| 49 | orl %eax,%ecx |
| 50 | roll $4,%eax |
| 51 | orl %ecx,%eax |
| 52 | andl $7,%eax |
| 53 | /* Negate the quotient bits if x*y<0. Avoid using an unpredictable branch. */ |
| 54 | movl -8(%rsp),%ecx |
| 55 | xorl -4(%rsp),%ecx |
| 56 | sarl $16,%ecx |
| 57 | sarl $16,%ecx |
| 58 | xorl %ecx,%eax |
| 59 | andl $1,%ecx |
| 60 | addl %ecx,%eax |
| 61 | /* Store the quotient and return. */ |
| 62 | movl %eax,(%rdi) |
| 63 | fstps -4(%rsp) |
| 64 | movss -4(%rsp),%xmm0 |
| 65 | ret |