mirror of
https://github.com/torvalds/linux.git
synced 2024-11-25 05:32:00 +00:00
9613736d85
This ensures no compiler-generated floating-point code can appear outside
kernel_fpu_{begin,end}() sections, and some architectures enforce this
separation.
Link: https://lkml.kernel.org/r/20240329072441.591471-15-samuel.holland@sifive.com
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: WANG Xuerui <git@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
38 lines
663 B
C
38 lines
663 B
C
// SPDX-License-Identifier: GPL-2.0+
|
|
|
|
#include <linux/errno.h>
|
|
|
|
#include "test_fpu.h"
|
|
|
|
int test_fpu(void)
|
|
{
|
|
/*
|
|
* This sequence of operations tests that rounding mode is
|
|
* to nearest and that denormal numbers are supported.
|
|
* Volatile variables are used to avoid compiler optimizing
|
|
* the calculations away.
|
|
*/
|
|
volatile double a, b, c, d, e, f, g;
|
|
|
|
a = 4.0;
|
|
b = 1e-15;
|
|
c = 1e-310;
|
|
|
|
/* Sets precision flag */
|
|
d = a + b;
|
|
|
|
/* Result depends on rounding mode */
|
|
e = a + b / 2;
|
|
|
|
/* Denormal and very large values */
|
|
f = b / c;
|
|
|
|
/* Depends on denormal support */
|
|
g = a + c * f;
|
|
|
|
if (d > a && e > a && g > a)
|
|
return 0;
|
|
else
|
|
return -EINVAL;
|
|
}
|