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/* Round to int long double floating-point values.
   IBM extended format long double version.
   Copyright (C) 2004, 2006 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

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

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

/* This has been coded in assembler because GCC makes such a mess of it
   when it's coded in C.  */

#include <sysdep.h>
#include <math_ldbl_opt.h>

	.section	".toc","aw"
.LC0:	/* 2**52 */
	.tc FD_43300000_0[TC],0x4330000000000000
	.section	".text"

ENTRY (__rintl)
	lfd	fp13,.LC0@toc(2)
	fabs	fp0,fp1
	fsub	fp12,fp13,fp13	/* generate 0.0  */
	fabs	fp9,fp2
	fcmpu	cr7,fp0,fp13	/* if (fabs(x) > TWO52)  */
	fcmpu	cr6,fp1,fp12	/* if (x > 0.0)  */
	bnl-	cr7,.L2
	fmr	fp2,fp12
	bng-	cr6,.L1
	fadd	fp1,fp1,fp13	/* x+= TWO52;  */
	fsub	fp1,fp1,fp13	/* x-= TWO52;  */
	fabs	fp1,fp1		/* if (x == 0.0)  */
	blr			/* x = 0.0; */
.L1:
	bnllr-	cr6		/* if (x < 0.0)  */
	fsub	fp1,fp1,fp13	/* x-= TWO52;  */
	fadd	fp1,fp1,fp13	/* x+= TWO52;  */
	fnabs	fp1,fp1		/* if (x == 0.0)  */
	blr			/* x = -0.0; */

/* The high double is > TWO52 so we need to round the low double and
   perhaps the high double.  In this case we have to round the low
   double and handle any adjustment to the high double that may be
   caused by rounding (up).  This is complicated by the fact that the
   high double may already be rounded and the low double may have the
   opposite sign to compensate.This gets a bit tricky so we use the
   following algorithm:

   tau = floor(x_high/TWO52);
   x0 = x_high - tau;
   x1 = x_low + tau;
   r1 = rint(x1);
   y_high = x0 + r1;
   y_low = x0 - y_high + r1;
   return y;  */
.L2:
	fcmpu	cr7,fp9,fp13	/* if (|x_low| > TWO52)  */
	fcmpu	cr0,fp9,fp12	/* || (|x_low| == 0.0)  */
	fcmpu	cr5,fp2,fp12	/* if (x_low > 0.0)  */
	bgelr-	cr7		/*   return x;	*/
	beqlr-  cr0
	fdiv	fp8,fp1,fp13	/* x_high/TWO52  */
	
	bng-	cr6,.L6		/* if (x > 0.0)  */
	fctidz	fp0,fp8
	fcfid	fp8,fp0		/* tau = floor(x_high/TWO52);  */
	fadd	fp8,fp8,fp8	/* tau++; Make tau even  */
	bng	cr5,.L4		/* if (x_low > 0.0)  */
	fmr	fp3,fp1
	fmr	fp4,fp2
	b	.L5
.L4:				/* if (x_low < 0.0)  */
	fsub	fp3,fp1,fp8	/* x0 = x_high - tau;  */
	fadd	fp4,fp2,fp8	/* x1 = x_low + tau;  */
.L5:
	fadd	fp5,fp4,fp13	/* r1 = x1 + TWO52;  */
	fsub	fp5,fp5,fp13	/* r1 = r1 - TWO52;  */
	b	.L9
.L6:				/* if (x < 0.0)  */
	fctidz	fp0,fp8
	fcfid	fp8,fp0		/* tau = floor(x_high/TWO52);  */
	fadd	fp8,fp8,fp8	/* tau++; Make tau even  */	
	bnl	cr5,.L7		/* if (x_low < 0.0)  */
	fmr	fp3,fp1
	fmr	fp4,fp2
	b	.L8
.L7:				/* if (x_low > 0.0)  */
	fsub	fp3,fp1,fp8	/* x0 = x_high - tau;  */
	fadd	fp4,fp2,fp8	/* x1 = x_low + tau;  */
.L8:
	fsub	fp5,fp13,fp4	/* r1 = TWO52 - x1;  */
	fsub	fp0,fp5,fp13	/* r1 = - (r1 - TWO52);  */
	fneg	fp5,fp0
.L9:
	fadd	fp1,fp3,fp5	/* y_high = x0 + r1;  */
	fsub	fp2,fp3,fp1	/* y_low = x0 - y_high + r1;  */
	fadd	fp2,fp2,fp5
	blr
END (__rintl)

long_double_symbol (libm, __rintl, rintl)