Optimized nearbyint for PPC

1 files changed, 68 insertions, 0 deletions

diff --git a/sysdeps/powerpc/powerpc64/fpu/s_nearbyint.S b/sysdeps/powerpc/powerpc64/fpu/s_nearbyint.S
new file mode 100644
index 0000000000..436160f48e
--- /dev/null
+++ b/sysdeps/powerpc/powerpc64/fpu/s_nearbyint.S
@@ -0,0 +1,68 @@
+/* Round to int floating-point values.  PowerPC64 version.
+   Copyright (C) 2011 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Adhemerval Zanella <azanella@br.ibm.com>, 2011
+
+   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>
+
+
+/* double [fp1] nearbyint(double [fp1] x) */
+
+	.section	".toc","aw"
+.LC0:	/* 2**52 */
+	.tc FD_43300000_0[TC],0x4330000000000000
+	.section	".text"
+
+EALIGN (__nearbyint, 4, 0)
+	CALL_MCOUNT 0
+	fabs	fp0,fp1
+	lfd	fp13,.LC0@toc(2)
+	fcmpu	cr7,fp0,fp13	/* if (fabs(x) > TWO52)  */
+	bgelr	cr7
+	fsub	fp12,fp13,fp13	/* generate 0.0 */
+	fcmpu	cr7,fp1,fp12	/* if (x > 0.0) */
+	ble	cr7, L(lessthanzero)
+	mtfsb0	4*cr7+lt	/* Disable FE_INEXACT exception */
+	fadd	fp1,fp1,fp13	/* x+= TWO52 */
+	fsub	fp1,fp1,fp13	/* x-= TWO52 */
+	fabs	fp1,fp1		/* if (x == 0.0) */
+	mtfsb0	4*cr1+eq	/* Clear any FE_INEXACT exception */
+	blr			/* x = 0.0; */
+L(lessthanzero):
+	bgelr	cr7		/* if (x < 0.0) */
+	mtfsb0	4*cr7+lt
+	fsub	fp1,fp1,fp13	/* x -= TWO52 */
+	fadd	fp1,fp1,fp13	/* x += TWO52 */
+	fnabs	fp1,fp1		/* if (x == 0.0) */
+	mtfsb0	4*cr1+eq
+	blr			/* x = -0.0; */
+END (__nearbyint)
+
+weak_alias (__nearbyint, nearbyint)
+
+#ifdef NO_LONG_DOUBLE
+weak_alias (__nearbyint, nearbyint)
+strong_alias (__nearbyint, __nearbyintl)
+#endif
+#if LONG_DOUBLE_COMPAT(libm, GLIBC_2_0)
+compat_symbol (libm, __nearbyint, nearbyintl, GLIBC_2_0)
+#endif