lshift.asm revision 1.1.1.1
1dnl x86 mpn_lshift -- mpn left shift. 2 3dnl Copyright 1992, 1994, 1996, 1999, 2000, 2001, 2002 Free Software 4dnl Foundation, Inc. 5dnl 6dnl This file is part of the GNU MP Library. 7dnl 8dnl The GNU MP Library is free software; you can redistribute it and/or 9dnl modify it under the terms of the GNU Lesser General Public License as 10dnl published by the Free Software Foundation; either version 3 of the 11dnl License, or (at your option) any later version. 12dnl 13dnl The GNU MP Library is distributed in the hope that it will be useful, 14dnl but WITHOUT ANY WARRANTY; without even the implied warranty of 15dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16dnl Lesser General Public License for more details. 17dnl 18dnl You should have received a copy of the GNU Lesser General Public License 19dnl along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. 20 21include(`../config.m4') 22 23 24C cycles/limb 25C P54: 7.5 26C P55: 7.0 27C P6: 2.5 28C K6: 4.5 29C K7: 5.0 30C P4: 14.5 31 32 33C mp_limb_t mpn_lshift (mp_ptr dst, mp_srcptr src, mp_size_t size, 34C unsigned shift); 35 36defframe(PARAM_SHIFT,16) 37defframe(PARAM_SIZE, 12) 38defframe(PARAM_SRC, 8) 39defframe(PARAM_DST, 4) 40 41 TEXT 42 ALIGN(8) 43PROLOGUE(mpn_lshift) 44 45 pushl %edi 46 pushl %esi 47 pushl %ebx 48deflit(`FRAME',12) 49 50 movl PARAM_DST,%edi 51 movl PARAM_SRC,%esi 52 movl PARAM_SIZE,%edx 53 movl PARAM_SHIFT,%ecx 54 55 subl $4,%esi C adjust src 56 57 movl (%esi,%edx,4),%ebx C read most significant limb 58 xorl %eax,%eax 59 shldl( %cl, %ebx, %eax) C compute carry limb 60 decl %edx 61 jz L(end) 62 pushl %eax C push carry limb onto stack 63 testb $1,%dl 64 jnz L(1) C enter loop in the middle 65 movl %ebx,%eax 66 67 ALIGN(8) 68L(oop): movl (%esi,%edx,4),%ebx C load next lower limb 69 shldl( %cl, %ebx, %eax) C compute result limb 70 movl %eax,(%edi,%edx,4) C store it 71 decl %edx 72L(1): movl (%esi,%edx,4),%eax 73 shldl( %cl, %eax, %ebx) 74 movl %ebx,(%edi,%edx,4) 75 decl %edx 76 jnz L(oop) 77 78 shll %cl,%eax C compute least significant limb 79 movl %eax,(%edi) C store it 80 81 popl %eax C pop carry limb 82 83 popl %ebx 84 popl %esi 85 popl %edi 86 ret 87 88L(end): shll %cl,%ebx C compute least significant limb 89 movl %ebx,(%edi) C store it 90 91 popl %ebx 92 popl %esi 93 popl %edi 94 ret 95 96EPILOGUE() 97