summaryrefslogtreecommitdiffstats
path: root/lib/zstd/common/portability_macros.h
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2022-12-19 12:26:03 -0600
committerLinus Torvalds <torvalds@linux-foundation.org>2022-12-19 12:26:03 -0600
commit158738ea75059fb4ddf812e2cb9fe1ff6e22bc70 (patch)
tree41aa6e3bc58ed933dfcb885796fa3ba581ea2573 /lib/zstd/common/portability_macros.h
parentaeba12b26c79fc35e07e511f692a8907037d95da (diff)
parent70d822cfb782ebed5c41bdad9fa520b5ec1c6923 (diff)
downloadlinux-158738ea75059fb4ddf812e2cb9fe1ff6e22bc70.tar.bz2
Merge tag 'zstd-linus-v6.2' of https://github.com/terrelln/linux
Pull zstd updates from Nick Terrell: "Update the kernel to upstream zstd v1.5.2 [0]. Specifically to the tag v1.5.2-kernel [1] which includes several cherrypicked fixes for the kernel on top of v1.5.2. Excepting the MAINTAINERS change, all the changes in this can be generated by: git clone https://github.com/facebook/zstd cd zstd/contrib/linux-kernel git checkout v1.5.2-kernel LINUX=/path/to/linux/repo make import Additionally, this includes several minor typo fixes, which have all been fixed upstream so they are maintained on the next import" Link: https://github.com/facebook/zstd/releases/tag/v1.5.2 [0] Link: https://github.com/facebook/zstd/tree/v1.5.2-kernel [1] Link: https://lore.kernel.org/lkml/20221024202606.404049-1-nickrterrell@gmail.com/ Link: https://github.com/torvalds/linux/commit/637a642f5ca5e850186bb64ac75ebb0f124b458d * tag 'zstd-linus-v6.2' of https://github.com/terrelln/linux: zstd: import usptream v1.5.2 zstd: Move zstd-common module exports to zstd_common_module.c lib: zstd: Fix comment typo lib: zstd: fix repeated words in comments MAINTAINERS: git://github -> https://github.com for terrelln lib: zstd: clean up double word in comment.
Diffstat (limited to 'lib/zstd/common/portability_macros.h')
-rw-r--r--lib/zstd/common/portability_macros.h93
1 files changed, 93 insertions, 0 deletions
diff --git a/lib/zstd/common/portability_macros.h b/lib/zstd/common/portability_macros.h
new file mode 100644
index 000000000000..0e3b2c0a527d
--- /dev/null
+++ b/lib/zstd/common/portability_macros.h
@@ -0,0 +1,93 @@
+/*
+ * Copyright (c) Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under both the BSD-style license (found in the
+ * LICENSE file in the root directory of this source tree) and the GPLv2 (found
+ * in the COPYING file in the root directory of this source tree).
+ * You may select, at your option, one of the above-listed licenses.
+ */
+
+#ifndef ZSTD_PORTABILITY_MACROS_H
+#define ZSTD_PORTABILITY_MACROS_H
+
+/*
+ * This header file contains macro defintions to support portability.
+ * This header is shared between C and ASM code, so it MUST only
+ * contain macro definitions. It MUST not contain any C code.
+ *
+ * This header ONLY defines macros to detect platforms/feature support.
+ *
+ */
+
+
+/* compat. with non-clang compilers */
+#ifndef __has_attribute
+ #define __has_attribute(x) 0
+#endif
+
+/* compat. with non-clang compilers */
+#ifndef __has_builtin
+# define __has_builtin(x) 0
+#endif
+
+/* compat. with non-clang compilers */
+#ifndef __has_feature
+# define __has_feature(x) 0
+#endif
+
+/* detects whether we are being compiled under msan */
+
+/* detects whether we are being compiled under asan */
+
+/* detects whether we are being compiled under dfsan */
+
+/* Mark the internal assembly functions as hidden */
+#ifdef __ELF__
+# define ZSTD_HIDE_ASM_FUNCTION(func) .hidden func
+#else
+# define ZSTD_HIDE_ASM_FUNCTION(func)
+#endif
+
+/* Enable runtime BMI2 dispatch based on the CPU.
+ * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default.
+ */
+#ifndef DYNAMIC_BMI2
+ #if ((defined(__clang__) && __has_attribute(__target__)) \
+ || (defined(__GNUC__) \
+ && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))) \
+ && (defined(__x86_64__) || defined(_M_X64)) \
+ && !defined(__BMI2__)
+ # define DYNAMIC_BMI2 1
+ #else
+ # define DYNAMIC_BMI2 0
+ #endif
+#endif
+
+/*
+ * Only enable assembly for GNUC comptabile compilers,
+ * because other platforms may not support GAS assembly syntax.
+ *
+ * Only enable assembly for Linux / MacOS, other platforms may
+ * work, but they haven't been tested. This could likely be
+ * extended to BSD systems.
+ *
+ * Disable assembly when MSAN is enabled, because MSAN requires
+ * 100% of code to be instrumented to work.
+ */
+#define ZSTD_ASM_SUPPORTED 1
+
+/*
+ * Determines whether we should enable assembly for x86-64
+ * with BMI2.
+ *
+ * Enable if all of the following conditions hold:
+ * - ASM hasn't been explicitly disabled by defining ZSTD_DISABLE_ASM
+ * - Assembly is supported
+ * - We are compiling for x86-64 and either:
+ * - DYNAMIC_BMI2 is enabled
+ * - BMI2 is supported at compile time
+ */
+#define ZSTD_ENABLE_ASM_X86_64_BMI2 0
+
+#endif /* ZSTD_PORTABILITY_MACROS_H */