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+/* long double trunc function.
+ 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. */
+
+#include <sysdep.h>
+#include <math_ldbl_opt.h>
+
+ .section ".toc","aw"
+.LC0: /* 2**52 */
+ .tc FD_43300000_0[TC],0x4330000000000000
+.LC1: /* 0.5 */
+ .tc FD_3fe00000_0[TC],0x3fe0000000000000
+ .section ".text"
+
+/* long double [fp1,fp2] truncl (long double x [fp1,fp2]) */
+
+ENTRY (__truncl)
+ mffs fp11 /* Save current FPU rounding mode. */
+ lfd fp13,.LC0@toc(2)
+ fabs fp0,fp1
+ fabs fp9,fp2
+ fsub fp12,fp13,fp13 /* generate 0.0 */
+ fcmpu cr7,fp0,fp13 /* if (fabs(x) > TWO52) */
+ fcmpu cr6,fp1,fp12 /* if (x > 0.0) */
+ bnl- cr7,.L2
+ mtfsfi 7,1 /* Set rounding mode toward 0. */
+ ble- cr6,.L1
+ fneg fp2,fp12
+ fadd fp1,fp1,fp13 /* x+= TWO52; */
+ fsub fp1,fp1,fp13 /* x-= TWO52; */
+ fabs fp1,fp1 /* if (x == 0.0) x = 0.0; */
+.L0:
+ mtfsf 0x01,fp11 /* restore previous rounding mode. */
+ blr
+.L1:
+ fneg fp2,fp12
+ bge- cr6,.L0 /* if (x < 0.0) */
+ fsub fp1,fp1,fp13 /* x-= TWO52; */
+ fadd fp1,fp1,fp13 /* x+= TWO52; */
+ fnabs fp1,fp1 /* if (x == 0.0) x = -0.0; */
+ mtfsf 0x01,fp11 /* restore previous rounding mode. */
+ blr
+
+/* 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
+ mtfsfi 7,1 /* Set rounding mode toward 0. */
+ 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 = r1 + 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,fp4,fp13 /* r1-= TWO52; */
+ fadd fp5,fp5,fp13 /* r1+= TWO52; */
+.L9:
+ mtfsf 0x01,fp11 /* restore previous rounding mode. */
+ fadd fp1,fp3,fp5 /* y_high = x0 + r1; */
+ fsub fp2,fp3,fp1 /* y_low = x0 - y_high + r1; */
+ fadd fp2,fp2,fp5
+ blr
+END (__truncl)
+
+long_double_symbol (libm, __truncl, truncl)