gcc/gmp/mpn/ia64/invert_limb.asm

dnl  IA-64 mpn_invert_limb -- Invert a normalized limb.

dnl  Copyright 2000, 2002, 2004 Free Software Foundation, Inc.

dnl  This file is part of the GNU MP Library.

dnl  The GNU MP Library is free software; you can redistribute it and/or modify
dnl  it under the terms of the GNU Lesser General Public License as published
dnl  by the Free Software Foundation; either version 3 of the License, or (at
dnl  your option) any later version.

dnl  The GNU MP Library is distributed in the hope that it will be useful, but
dnl  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
dnl  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
dnl  License for more details.

dnl  You should have received a copy of the GNU Lesser General Public License
dnl  along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.

include(`../config.m4')

C INPUT PARAMETERS
C d = r32

C           cycles
C Itanium:    ?
C Itanium 2:  50+6

C It should be possible to avoid the xmpy.hu and the following tests by
C explicitly chopping in the last fma.  That would save about 10 cycles.

ASM_START()
	.sdata
	.align 16
ifdef(`HAVE_DOUBLE_IEEE_LITTLE_ENDIAN',`
.LC0:	data4 0x00000000, 0x80000000, 0x0000403f, 0x00000000	C 2^64
.LC1:	data4 0x00000000, 0x80000000, 0x0000407f, 0x00000000	C 2^128

',`ifdef(`HAVE_DOUBLE_IEEE_BIG_ENDIAN',`
.LC0:	data4 0x403f8000, 0x00000000, 0x00000000, 0x00000000	C 2^64
.LC1:	data4 0x407f8000, 0x00000000, 0x00000000, 0x00000000	C 2^128

',`m4_error(`Oops, need to know float endianness
')')')


PROLOGUE(mpn_invert_limb)
		C 00
	addl		r14 = @gprel(.LC0), gp
	addl		r15 = @gprel(.LC1), gp
	setf.sig	f7 = r32
	add		r9 = r32, r32		C check for d = 2^63
	;;	C 01
	ldfe		f10 = [r14]		C 2^64
	ldfe		f8 = [r15]		C 2^128
	cmp.eq		p6, p0 = 0, r9		C check for d = 2^63
	mov		r8 = -1			C retval for 2^63
   (p6)	br.ret.spnt.many b0
	;;	C 07
	fmpy.s1		f11 = f7, f10		C f11 = d * 2^64
	fnma.s1		f6 = f7, f10, f8	C f6 = 2^128 - d * 2^64
	;;	C 11
	frcpa.s1	f8, p6 = f6, f7
	;;	C 15
   (p6)	fnma.s1		f9 = f7, f8, f1
   (p6)	fmpy.s1		f10 = f6, f8
	;;	C 19
   (p6)	fmpy.s1		f11 = f9, f9
   (p6)	fma.s1		f10 = f9, f10, f10
	;;	C 23
   (p6)	fma.s1		f8 = f9, f8, f8
   (p6)	fma.s1		f9 = f11, f10, f10
	;;	C 27
   (p6)	fma.s1		f8 = f11, f8, f8
   (p6)	fnma.s1		f10 = f7, f9, f6
	;;	C 31
   (p6)	fma.s1		f8 = f10, f8, f9
	;;	C 35
	fcvt.fxu.trunc.s1 f8 = f8
	;;	C 39
	getf.sig	r8 = f8
	xmpy.hu		f10 = f8, f7		C di * d
	;;	C 43
	getf.sig	r14 = f10
	andcm		r9 = -1, r32		C one's complement
	;;	C 48
	cmp.ltu		p6, p0 = r9, r14	C got overflow?
	;;	C 49
   (p6)	add		r8 = -1, r8		C adjust di down
	br.ret.sptk.many b0
EPILOGUE()
ASM_END()