From 5b992add7d32d3106f121c85ad99d2986dc3b8e6 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 14 Apr 2020 11:37:29 -0300 Subject: tools headers: Adopt verbatim copy of compiletime_assert() from kernel sources Will be needed when syncing the linux/bits.h header, in the next cset. Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Signed-off-by: Arnaldo Carvalho de Melo --- tools/include/linux/compiler.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'tools/include/linux/compiler.h') diff --git a/tools/include/linux/compiler.h b/tools/include/linux/compiler.h index 1827c2f973f9..180f7714a5f1 100644 --- a/tools/include/linux/compiler.h +++ b/tools/include/linux/compiler.h @@ -10,6 +10,32 @@ # define __compiletime_error(message) #endif +#ifdef __OPTIMIZE__ +# define __compiletime_assert(condition, msg, prefix, suffix) \ + do { \ + extern void prefix ## suffix(void) __compiletime_error(msg); \ + if (!(condition)) \ + prefix ## suffix(); \ + } while (0) +#else +# define __compiletime_assert(condition, msg, prefix, suffix) do { } while (0) +#endif + +#define _compiletime_assert(condition, msg, prefix, suffix) \ + __compiletime_assert(condition, msg, prefix, suffix) + +/** + * compiletime_assert - break build and emit msg if condition is false + * @condition: a compile-time constant condition to check + * @msg: a message to emit if condition is false + * + * In tradition of POSIX assert, this macro will break the build if the + * supplied condition is *false*, emitting the supplied error message if the + * compiler has support to do so. + */ +#define compiletime_assert(condition, msg) \ + _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) + /* Optimization barrier */ /* The "volatile" is due to gcc bugs */ #define barrier() __asm__ __volatile__("": : :"memory") -- cgit v1.2.3 From 21f2b7c13335eeec498569927d87c7381c3b54fa Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Sat, 30 May 2020 01:20:13 -0700 Subject: tools compiler.h: Add attribute to disable tail calls Tail call optimizations can remove stack frames that are used in unwinding tests. Add an attribute that can be used to disable the tail call optimization. Tested on clang and GCC. Committer notes: Old versions of clang don't like that __attribute__((optimize)), so add an ifdef to make it go away. Signed-off-by: Ian Rogers Cc: Alexander Shishkin Cc: Alexei Starovoitov Cc: clang-built-linux@googlegroups.com Cc: Jakub Kicinski Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Quentin Monnet Cc: Stephane Eranian Link: http://lore.kernel.org/lkml/20200530082015.39162-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/include/linux/compiler-gcc.h | 12 ++++++++++++ tools/include/linux/compiler.h | 3 +++ 2 files changed, 15 insertions(+) (limited to 'tools/include/linux/compiler.h') diff --git a/tools/include/linux/compiler-gcc.h b/tools/include/linux/compiler-gcc.h index 95c072b70d0e..b9d4322e1e65 100644 --- a/tools/include/linux/compiler-gcc.h +++ b/tools/include/linux/compiler-gcc.h @@ -27,6 +27,18 @@ #define __pure __attribute__((pure)) #endif #define noinline __attribute__((noinline)) +#ifdef __has_attribute +#if __has_attribute(disable_tail_calls) +#define __no_tail_call __attribute__((disable_tail_calls)) +#endif +#endif +#ifndef __no_tail_call +#if GCC_VERSION > 40201 +#define __no_tail_call __attribute__((optimize("no-optimize-sibling-calls"))) +#else +#define __no_tail_call +#endif +#endif #ifndef __packed #define __packed __attribute__((packed)) #endif diff --git a/tools/include/linux/compiler.h b/tools/include/linux/compiler.h index 180f7714a5f1..9f9002734e19 100644 --- a/tools/include/linux/compiler.h +++ b/tools/include/linux/compiler.h @@ -47,6 +47,9 @@ #ifndef noinline #define noinline #endif +#ifndef __no_tail_call +#define __no_tail_call +#endif /* Are two types/vars the same type (ignoring qualifiers)? */ #ifndef __same_type -- cgit v1.2.3