linux-stable/include/linux/compiler-intel.h
Michael S. Tsirkin 3e2ffd655c include/linux/compiler*.h: fix OPTIMIZER_HIDE_VAR
Since commit 815f0ddb34 ("include/linux/compiler*.h: make compiler-*.h
mutually exclusive") clang no longer reuses the OPTIMIZER_HIDE_VAR macro
from compiler-gcc - instead it gets the version in
include/linux/compiler.h.  Unfortunately that version doesn't actually
prevent compiler from optimizing out the variable.

Fix up by moving the macro out from compiler-gcc.h to compiler.h.
Compilers without incline asm support will keep working
since it's protected by an ifdef.

Also fix up comments to match reality since we are no longer overriding
any macros.

Build-tested with gcc and clang.

Fixes: 815f0ddb34 ("include/linux/compiler*.h: make compiler-*.h mutually exclusive")
Cc: Eli Friedman <efriedma@codeaurora.org>
Cc: Joe Perches <joe@perches.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
2019-01-09 11:36:41 +01:00

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949 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_COMPILER_TYPES_H
#error "Please don't include <linux/compiler-intel.h> directly, include <linux/compiler.h> instead."
#endif
#ifdef __ECC
/* Compiler specific definitions for Intel ECC compiler */
#include <asm/intrinsics.h>
/* Intel ECC compiler doesn't support gcc specific asm stmts.
* It uses intrinsics to do the equivalent things.
*/
#define barrier() __memory_barrier()
#define barrier_data(ptr) barrier()
#define RELOC_HIDE(ptr, off) \
({ unsigned long __ptr; \
__ptr = (unsigned long) (ptr); \
(typeof(ptr)) (__ptr + (off)); })
/* This should act as an optimization barrier on var.
* Given that this compiler does not have inline assembly, a compiler barrier
* is the best we can do.
*/
#define OPTIMIZER_HIDE_VAR(var) barrier()
#endif
/* icc has this, but it's called _bswap16 */
#define __HAVE_BUILTIN_BSWAP16__
#define __builtin_bswap16 _bswap16