glibc/sysdeps/x86_64/fpu/multiarch/s_floor.S
Joseph Myers 5ff81530dd Do not raise "inexact" from x86_64 SSE4.1 ceil, floor (bug 15479).
Continuing fixes for ceil and floor functions not to raise the
"inexact" exception, this patch fixes the x86_64 SSE4.1 versions.  The
roundss / roundsd instructions take an immediate operand that
determines the rounding mode and whether to raise "inexact"; this just
needs bit 3 set to disable "inexact", which this patch does.

Remark: we don't have an SSE4.1 version of trunc / truncf (using this
instruction with operand 11); I'd expect one to make sense, but of
course it should be benchmarked against the existing C code.  I'll
file a bug in Bugzilla for the lack of such a version.

Tested for x86_64.

	[BZ #15479]
	* sysdeps/x86_64/fpu/multiarch/s_ceil.S (__ceil_sse41): Set bit 3
	of immediate operand to rounding instruction.
	* sysdeps/x86_64/fpu/multiarch/s_ceilf.S (__ceilf_sse41):
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/s_floor.S (__floor_sse41):
	Likewise.
	* sysdeps/x86_64/fpu/multiarch/s_floorf.S (__floorf_sse41):
	Likewise.
2016-05-24 21:11:18 +00:00

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ArmAsm

/* Copyright (C) 2011-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@gmail.come>, 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, see
<http://www.gnu.org/licenses/>. */
#include <machine/asm.h>
#include <init-arch.h>
ENTRY(__floor)
.type __floor, @gnu_indirect_function
LOAD_RTLD_GLOBAL_RO_RDX
leaq __floor_sse41(%rip), %rax
HAS_CPU_FEATURE (SSE4_1)
jnz 2f
leaq __floor_c(%rip), %rax
2: ret
END(__floor)
weak_alias (__floor, floor)
ENTRY(__floor_sse41)
roundsd $9, %xmm0, %xmm0
ret
END(__floor_sse41)