summaryrefslogtreecommitdiffstats
path: root/tools/testing/selftests/rseq/compiler.h
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /tools/testing/selftests/rseq/compiler.h
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/rseq/compiler.h')
-rw-r--r--tools/testing/selftests/rseq/compiler.h62
1 files changed, 62 insertions, 0 deletions
diff --git a/tools/testing/selftests/rseq/compiler.h b/tools/testing/selftests/rseq/compiler.h
new file mode 100644
index 0000000000..49d62fbd6d
--- /dev/null
+++ b/tools/testing/selftests/rseq/compiler.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: LGPL-2.1-only OR MIT */
+/*
+ * rseq/compiler.h
+ *
+ * Work-around asm goto compiler bugs.
+ *
+ * (C) Copyright 2021 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ */
+
+#ifndef RSEQ_COMPILER_H
+#define RSEQ_COMPILER_H
+
+/*
+ * gcc prior to 4.8.2 miscompiles asm goto.
+ * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670
+ *
+ * gcc prior to 8.1.0 miscompiles asm goto at O1.
+ * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103908
+ *
+ * clang prior to version 13.0.1 miscompiles asm goto at O2.
+ * https://github.com/llvm/llvm-project/issues/52735
+ *
+ * Work around these issues by adding a volatile inline asm with
+ * memory clobber in the fallthrough after the asm goto and at each
+ * label target. Emit this for all compilers in case other similar
+ * issues are found in the future.
+ */
+#define rseq_after_asm_goto() asm volatile ("" : : : "memory")
+
+/* Combine two tokens. */
+#define RSEQ__COMBINE_TOKENS(_tokena, _tokenb) \
+ _tokena##_tokenb
+#define RSEQ_COMBINE_TOKENS(_tokena, _tokenb) \
+ RSEQ__COMBINE_TOKENS(_tokena, _tokenb)
+
+#ifdef __cplusplus
+#define rseq_unqual_scalar_typeof(x) \
+ std::remove_cv<std::remove_reference<decltype(x)>::type>::type
+#else
+#define rseq_scalar_type_to_expr(type) \
+ unsigned type: (unsigned type)0, \
+ signed type: (signed type)0
+
+/*
+ * Use C11 _Generic to express unqualified type from expression. This removes
+ * volatile qualifier from expression type.
+ */
+#define rseq_unqual_scalar_typeof(x) \
+ __typeof__( \
+ _Generic((x), \
+ char: (char)0, \
+ rseq_scalar_type_to_expr(char), \
+ rseq_scalar_type_to_expr(short), \
+ rseq_scalar_type_to_expr(int), \
+ rseq_scalar_type_to_expr(long), \
+ rseq_scalar_type_to_expr(long long), \
+ default: (x) \
+ ) \
+ )
+#endif
+
+#endif /* RSEQ_COMPILER_H_ */