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authorLinus Torvalds <torvalds@linux-foundation.org>2024-05-22 18:59:29 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2024-05-22 18:59:29 -0700
commitc760b3725e52403dc1b28644fb09c47a83cacea6 (patch)
tree652d83ee1ccf1ea723ba68dde69c03d64bd49fa3 /lib/test_fpu_impl.c
parent5c6f4d68e2aca67e425b7227369ec9fde8adfb6d (diff)
parentdb3e24a02e29b507c24c0adb4d22914c65dab763 (diff)
Merge tag 'mm-nonmm-stable-2024-05-22-17-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull more non-mm updates from Andrew Morton: - A series ("kbuild: enable more warnings by default") from Arnd Bergmann which enables a number of additional build-time warnings. We fixed all the fallout which we could find, there may still be a few stragglers. - Samuel Holland has developed the series "Unified cross-architecture kernel-mode FPU API". This does a lot of consolidation of per-architecture kernel-mode FPU usage and enables the use of newer AMD GPUs on RISC-V. - Tao Su has fixed some selftests build warnings in the series "Selftests: Fix compilation warnings due to missing _GNU_SOURCE definition". - This pull also includes a nilfs2 fixup from Ryusuke Konishi. * tag 'mm-nonmm-stable-2024-05-22-17-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (23 commits) nilfs2: make block erasure safe in nilfs_finish_roll_forward() selftests/harness: use 1024 in place of LINE_MAX Revert "selftests/harness: remove use of LINE_MAX" selftests/fpu: allow building on other architectures selftests/fpu: move FP code to a separate translation unit drm/amd/display: use ARCH_HAS_KERNEL_FPU_SUPPORT drm/amd/display: only use hard-float, not altivec on powerpc riscv: add support for kernel-mode FPU x86: implement ARCH_HAS_KERNEL_FPU_SUPPORT powerpc: implement ARCH_HAS_KERNEL_FPU_SUPPORT LoongArch: implement ARCH_HAS_KERNEL_FPU_SUPPORT lib/raid6: use CC_FLAGS_FPU for NEON CFLAGS arm64: crypto: use CC_FLAGS_FPU for NEON CFLAGS arm64: implement ARCH_HAS_KERNEL_FPU_SUPPORT ARM: crypto: use CC_FLAGS_FPU for NEON CFLAGS ARM: implement ARCH_HAS_KERNEL_FPU_SUPPORT arch: add ARCH_HAS_KERNEL_FPU_SUPPORT x86/fpu: fix asm/fpu/types.h include guard kbuild: enable -Wcast-function-type-strict unconditionally kbuild: enable -Wformat-truncation on clang ...
Diffstat (limited to 'lib/test_fpu_impl.c')
-rw-r--r--lib/test_fpu_impl.c37
1 files changed, 37 insertions, 0 deletions
diff --git a/lib/test_fpu_impl.c b/lib/test_fpu_impl.c
new file mode 100644
index 000000000000..777894dbbe86
--- /dev/null
+++ b/lib/test_fpu_impl.c
@@ -0,0 +1,37 @@
+// 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;
+}