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![Samuel Holland](/assets/img/avatar_default.png)
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+
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#include <linux/errno.h>
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#include "test_fpu.h"
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int test_fpu(void)
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{
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/*
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* This sequence of operations tests that rounding mode is
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* to nearest and that denormal numbers are supported.
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* Volatile variables are used to avoid compiler optimizing
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* the calculations away.
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*/
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volatile double a, b, c, d, e, f, g;
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a = 4.0;
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b = 1e-15;
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c = 1e-310;
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/* Sets precision flag */
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d = a + b;
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/* Result depends on rounding mode */
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e = a + b / 2;
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/* Denormal and very large values */
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f = b / c;
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/* Depends on denormal support */
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g = a + c * f;
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if (d > a && e > a && g > a)
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return 0;
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else
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return -EINVAL;
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}
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