1/* ix87 specific frexp implementation for long double. 2 Copyright (C) 1997, 2000, 2001 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. 5 6 The GNU C Library is free software; you can redistribute it and/or 7 modify it under the terms of the GNU Lesser General Public 8 License as published by the Free Software Foundation; either 9 version 2.1 of the License, or (at your option) any later version. 10 11 The GNU C Library is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 Lesser General Public License for more details. 15 16 You should have received a copy of the GNU Lesser General Public 17 License along with the GNU C Library; if not, write to the Free 18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 19 02111-1307 USA. */ 20 21#include <machine/asm.h> 22#include "bp-sym.h" 23#include "bp-asm.h" 24 25#ifdef __ELF__ 26 .section .rodata 27#else 28 .text 29#endif 30 31 .align ALIGNARG(4) 32 ASM_TYPE_DIRECTIVE(two64,@object) 33two64: .byte 0, 0, 0, 0, 0, 0, 0xf0, 0x43 34 ASM_SIZE_DIRECTIVE(two64) 35 36#ifdef PIC 37#define MO(op) op##@GOTOFF(%edx) 38#else 39#define MO(op) op 40#endif 41 42#define PARMS LINKAGE /* no space for saved regs */ 43#define VAL0 PARMS 44#define VAL1 VAL0+4 45#define VAL2 VAL1+4 46#define EXPP VAL2+4 47 48 .text 49ENTRY (BP_SYM (__frexpl)) 50 ENTER 51 52 movl VAL0(%esp), %ecx 53 movl VAL2(%esp), %eax 54 orl VAL1(%esp), %ecx 55 movl %eax, %edx 56 andl $0x7fff, %eax 57 orl %eax, %ecx 58 jz 1f 59 xorl %ecx, %ecx 60 cmpl $0x7fff, %eax 61 je 1f 62 63 cmpl $0, %eax 64 jne 2f 65 66 fldt VAL0(%esp) 67#ifdef PIC 68 call 3f 693: popl %edx 70 addl $_GLOBAL_OFFSET_TABLE_+[.-3b], %edx 71#endif 72 73 fmull MO(two64) /* It's not necessary to use a 80bit factor */ 74 movl $-64, %ecx 75 fstpt VAL0(%esp) 76 fwait 77 movl VAL2(%esp), %eax 78 movl %eax, %edx 79 andl $0x7fff, %eax 80 812: andl $0x8000, %edx 82 subl $16382, %eax 83 orl $0x3ffe, %edx 84 addl %eax, %ecx 85 movl %edx, VAL2(%esp) 86 87 /* Store %ecx in the variable pointed to by the second argument, 88 get the factor from the stack and return. */ 891: movl EXPP(%esp), %eax 90 CHECK_BOUNDS_BOTH_WIDE (%eax, EXPP(%esp), $4) 91 fldt VAL0(%esp) 92 movl %ecx, (%eax) 93 94 LEAVE 95 ret 96END (BP_SYM (__frexpl)) 97weak_alias (BP_SYM (__frexpl), BP_SYM (frexpl)) 98