From d87c27d7ab143d58f358df5722be2b9675103d2e Mon Sep 17 00:00:00 2001 From: Alexey Galakhov Date: Mon, 6 Jul 2015 09:32:45 +0200 Subject: [PATCH] build: update compiler*.h to newest versions This adds the support for gcc 5.x and clang. Signed-off-by: Alexey Galakhov Signed-off-by: Sascha Hauer --- include/linux/compiler-clang.h | 12 ++ include/linux/compiler-gcc.h | 225 ++++++++++++++++++++++++++++----- include/linux/compiler-gcc3.h | 31 ----- include/linux/compiler-gcc4.h | 61 --------- include/linux/compiler-intel.h | 15 ++- include/linux/compiler.h | 99 ++++++++++++++- 6 files changed, 313 insertions(+), 130 deletions(-) create mode 100644 include/linux/compiler-clang.h delete mode 100644 include/linux/compiler-gcc3.h delete mode 100644 include/linux/compiler-gcc4.h diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h new file mode 100644 index 000000000..d1e49d52b --- /dev/null +++ b/include/linux/compiler-clang.h @@ -0,0 +1,12 @@ +#ifndef __LINUX_COMPILER_H +#error "Please don't include directly, include instead." +#endif + +/* Some compiler specific definitions are overwritten here + * for Clang compiler + */ + +#ifdef uninitialized_var +#undef uninitialized_var +#define uninitialized_var(x) x = *(&(x)) +#endif diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index 73dcf804b..dfaa7b3e9 100644 --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h @@ -5,11 +5,28 @@ /* * Common definitions for all gcc versions go here. */ - +#define GCC_VERSION (__GNUC__ * 10000 \ + + __GNUC_MINOR__ * 100 \ + + __GNUC_PATCHLEVEL__) /* Optimization barrier */ + /* The "volatile" is due to gcc bugs */ #define barrier() __asm__ __volatile__("": : :"memory") +/* + * This version is i.e. to prevent dead stores elimination on @ptr + * where gcc and llvm may behave differently when otherwise using + * normal barrier(): while gcc behavior gets along with a normal + * barrier(), llvm needs an explicit input variable to be assumed + * clobbered. The issue is as follows: while the inline asm might + * access any memory it wants, the compiler could have fit all of + * @ptr into memory registers instead, and since @ptr never escaped + * from that, it proofed that the inline asm wasn't touching any of + * it. This version works well with both compilers, i.e. we're telling + * the compiler that the inline asm absolutely may see the contents + * of @ptr. See also: https://llvm.org/bugs/show_bug.cgi?id=15495 + */ +#define barrier_data(ptr) __asm__ __volatile__("": :"r"(ptr) :"memory") /* * This macro obfuscates arithmetic on a variable address so that gcc @@ -29,39 +46,63 @@ * the inline assembly constraint from =g to =r, in this particular * case either is valid. */ -#define RELOC_HIDE(ptr, off) \ - ({ unsigned long __ptr; \ - __asm__ ("" : "=r"(__ptr) : "0"(ptr)); \ - (typeof(ptr)) (__ptr + (off)); }) +#define RELOC_HIDE(ptr, off) \ +({ \ + unsigned long __ptr; \ + __asm__ ("" : "=r"(__ptr) : "0"(ptr)); \ + (typeof(ptr)) (__ptr + (off)); \ +}) +/* Make the optimizer believe the variable can be manipulated arbitrarily. */ +#define OPTIMIZER_HIDE_VAR(var) \ + __asm__ ("" : "=r" (var) : "0" (var)) + +#ifdef __CHECKER__ +#define __must_be_array(a) 0 +#else /* &a[0] degrades to a pointer: a different type from an array */ -#define __must_be_array(a) \ - BUILD_BUG_ON_ZERO(__builtin_types_compatible_p(typeof(a), typeof(&a[0]))) +#define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) +#endif /* * Force always-inline if the user requests it so via the .config, * or if gcc is too old: */ -#if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ +#if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ !defined(CONFIG_OPTIMIZE_INLINING) || (__GNUC__ < 4) -# define inline inline __attribute__((always_inline)) -# define __inline__ __inline__ __attribute__((always_inline)) -# define __inline __inline __attribute__((always_inline)) +#define inline inline __attribute__((always_inline)) notrace +#define __inline__ __inline__ __attribute__((always_inline)) notrace +#define __inline __inline __attribute__((always_inline)) notrace +#else +/* A lot of inline functions can cause havoc with function tracing */ +#define inline inline notrace +#define __inline__ __inline__ notrace +#define __inline __inline notrace #endif -#define __deprecated __attribute__((deprecated)) -#define __packed __attribute__((packed)) -#define __weak __attribute__((weak)) +#define __always_inline inline __attribute__((always_inline)) +#define noinline __attribute__((noinline)) + +#define __deprecated __attribute__((deprecated)) +#define __packed __attribute__((packed)) +#define __weak __attribute__((weak)) +#define __alias(symbol) __attribute__((alias(#symbol))) /* - * it doesn't make sense on ARM (currently the only user of __naked) to trace - * naked functions because then mcount is called without stack and frame pointer - * being set up and there is no chance to restore the lr register to the value - * before mcount was called. + * it doesn't make sense on ARM (currently the only user of __naked) + * to trace naked functions because then mcount is called without + * stack and frame pointer being set up and there is no chance to + * restore the lr register to the value before mcount was called. + * + * The asm() bodies of naked functions often depend on standard calling + * conventions, therefore they must be noinline and noclone. + * + * GCC 4.[56] currently fail to enforce this, so we must do so ourselves. + * See GCC PR44290. */ -#define __naked __attribute__((naked)) notrace +#define __naked __attribute__((naked)) noinline __noclone notrace -#define __noreturn __attribute__((noreturn)) +#define __noreturn __attribute__((noreturn)) /* * From the GCC manual: @@ -73,15 +114,137 @@ * would be. * [...] */ -#define __pure __attribute__((pure)) -#define __aligned(x) __attribute__((aligned(x))) -#define __printf(a,b) __attribute__((format(printf,a,b))) -#define noinline __attribute__((noinline)) -#define __attribute_const__ __attribute__((__const__)) -#define __maybe_unused __attribute__((unused)) -#define __always_unused __attribute__((unused)) +#define __pure __attribute__((pure)) +#define __aligned(x) __attribute__((aligned(x))) +#define __printf(a, b) __attribute__((format(printf, a, b))) +#define __scanf(a, b) __attribute__((format(scanf, a, b))) +#define __attribute_const__ __attribute__((__const__)) +#define __maybe_unused __attribute__((unused)) +#define __always_unused __attribute__((unused)) -#define __gcc_header(x) #x -#define _gcc_header(x) __gcc_header(linux/compiler-gcc##x.h) -#define gcc_header(x) _gcc_header(x) -#include gcc_header(__GNUC__) +/* gcc version specific checks */ + +#if GCC_VERSION < 30200 +# error Sorry, your compiler is too old - please upgrade it. +#endif + +#if GCC_VERSION < 30300 +# define __used __attribute__((__unused__)) +#else +# define __used __attribute__((__used__)) +#endif + +#ifdef CONFIG_GCOV_KERNEL +# if GCC_VERSION < 30400 +# error "GCOV profiling support for gcc versions below 3.4 not included" +# endif /* __GNUC_MINOR__ */ +#endif /* CONFIG_GCOV_KERNEL */ + +#if GCC_VERSION >= 30400 +#define __must_check __attribute__((warn_unused_result)) +#endif + +#if GCC_VERSION >= 40000 + +/* GCC 4.1.[01] miscompiles __weak */ +#ifdef __KERNEL__ +# if GCC_VERSION >= 40100 && GCC_VERSION <= 40101 +# error Your version of gcc miscompiles the __weak directive +# endif +#endif + +#define __used __attribute__((__used__)) +#define __compiler_offsetof(a, b) \ + __builtin_offsetof(a, b) + +#if GCC_VERSION >= 40100 && GCC_VERSION < 40600 +# define __compiletime_object_size(obj) __builtin_object_size(obj, 0) +#endif + +#if GCC_VERSION >= 40300 +/* Mark functions as cold. gcc will assume any path leading to a call + * to them will be unlikely. This means a lot of manual unlikely()s + * are unnecessary now for any paths leading to the usual suspects + * like BUG(), printk(), panic() etc. [but let's keep them for now for + * older compilers] + * + * Early snapshots of gcc 4.3 don't support this and we can't detect this + * in the preprocessor, but we can live with this because they're unreleased. + * Maketime probing would be overkill here. + * + * gcc also has a __attribute__((__hot__)) to move hot functions into + * a special section, but I don't see any sense in this right now in + * the kernel context + */ +#define __cold __attribute__((__cold__)) + +#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__) + +#ifndef __CHECKER__ +# define __compiletime_warning(message) __attribute__((warning(message))) +# define __compiletime_error(message) __attribute__((error(message))) +#endif /* __CHECKER__ */ +#endif /* GCC_VERSION >= 40300 */ + +#if GCC_VERSION >= 40500 +/* + * Mark a position in code as unreachable. This can be used to + * suppress control flow warnings after asm blocks that transfer + * control elsewhere. + * + * Early snapshots of gcc 4.5 don't support this and we can't detect + * this in the preprocessor, but we can live with this because they're + * unreleased. Really, we need to have autoconf for the kernel. + */ +#define unreachable() __builtin_unreachable() + +/* Mark a function definition as prohibited from being cloned. */ +#define __noclone __attribute__((__noclone__)) + +#endif /* GCC_VERSION >= 40500 */ + +#if GCC_VERSION >= 40600 +/* + * Tell the optimizer that something else uses this function or variable. + */ +#define __visible __attribute__((externally_visible)) +#endif + +/* + * GCC 'asm goto' miscompiles certain code sequences: + * + * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670 + * + * Work it around via a compiler barrier quirk suggested by Jakub Jelinek. + * + * (asm goto is automatically volatile - the naming reflects this.) + */ +#define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0) + +#ifdef CONFIG_ARCH_USE_BUILTIN_BSWAP +#if GCC_VERSION >= 40400 +#define __HAVE_BUILTIN_BSWAP32__ +#define __HAVE_BUILTIN_BSWAP64__ +#endif +#if GCC_VERSION >= 40800 || (defined(__powerpc__) && GCC_VERSION >= 40600) +#define __HAVE_BUILTIN_BSWAP16__ +#endif +#endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */ + +#if GCC_VERSION >= 50000 +#define KASAN_ABI_VERSION 4 +#elif GCC_VERSION >= 40902 +#define KASAN_ABI_VERSION 3 +#endif + +#endif /* gcc version >= 40000 specific checks */ + +#if !defined(__noclone) +#define __noclone /* not needed */ +#endif + +/* + * A trick to suppress uninitialized variable warning without generating any + * code + */ +#define uninitialized_var(x) x = x diff --git a/include/linux/compiler-gcc3.h b/include/linux/compiler-gcc3.h deleted file mode 100644 index b721129e0..000000000 --- a/include/linux/compiler-gcc3.h +++ /dev/null @@ -1,31 +0,0 @@ -#ifndef __LINUX_COMPILER_H -#error "Please don't include directly, include instead." -#endif - -#if __GNUC_MINOR__ < 2 -# error Sorry, your compiler is too old - please upgrade it. -#endif - -#if __GNUC_MINOR__ >= 3 -# define __used __attribute__((__used__)) -#else -# define __used __attribute__((__unused__)) -#endif - -#if __GNUC_MINOR__ >= 4 -#define __must_check __attribute__((warn_unused_result)) -#endif - -#ifdef CONFIG_GCOV_KERNEL -# if __GNUC_MINOR__ < 4 -# error "GCOV profiling support for gcc versions below 3.4 not included" -# endif /* __GNUC_MINOR__ */ -#endif /* CONFIG_GCOV_KERNEL */ - -/* - * A trick to suppress uninitialized variable warning without generating any - * code - */ -#define uninitialized_var(x) x = x - -#define __always_inline inline __attribute__((always_inline)) diff --git a/include/linux/compiler-gcc4.h b/include/linux/compiler-gcc4.h deleted file mode 100644 index 94dea3ffb..000000000 --- a/include/linux/compiler-gcc4.h +++ /dev/null @@ -1,61 +0,0 @@ -#ifndef __LINUX_COMPILER_H -#error "Please don't include directly, include instead." -#endif - -/* GCC 4.1.[01] miscompiles __weak */ -#ifdef __KERNEL__ -# if __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ <= 1 -# error Your version of gcc miscompiles the __weak directive -# endif -#endif - -#define __used __attribute__((__used__)) -#define __must_check __attribute__((warn_unused_result)) -#define __compiler_offsetof(a,b) __builtin_offsetof(a,b) -#define __always_inline inline __attribute__((always_inline)) - -/* - * A trick to suppress uninitialized variable warning without generating any - * code - */ -#define uninitialized_var(x) x = x - -#if __GNUC_MINOR__ >= 3 -/* Mark functions as cold. gcc will assume any path leading to a call - to them will be unlikely. This means a lot of manual unlikely()s - are unnecessary now for any paths leading to the usual suspects - like BUG(), printk(), panic() etc. [but let's keep them for now for - older compilers] - - Early snapshots of gcc 4.3 don't support this and we can't detect this - in the preprocessor, but we can live with this because they're unreleased. - Maketime probing would be overkill here. - - gcc also has a __attribute__((__hot__)) to move hot functions into - a special section, but I don't see any sense in this right now in - the kernel context */ -#define __cold __attribute__((__cold__)) - - -#if __GNUC_MINOR__ >= 5 -/* - * Mark a position in code as unreachable. This can be used to - * suppress control flow warnings after asm blocks that transfer - * control elsewhere. - * - * Early snapshots of gcc 4.5 don't support this and we can't detect - * this in the preprocessor, but we can live with this because they're - * unreleased. Really, we need to have autoconf for the kernel. - */ -#define unreachable() __builtin_unreachable() -#endif - -#endif - -#if __GNUC_MINOR__ > 0 -#define __compiletime_object_size(obj) __builtin_object_size(obj, 0) -#endif -#if __GNUC_MINOR__ >= 4 -#define __compiletime_warning(message) __attribute__((warning(message))) -#define __compiletime_error(message) __attribute__((error(message))) -#endif diff --git a/include/linux/compiler-intel.h b/include/linux/compiler-intel.h index d8e636e56..58daccca9 100644 --- a/include/linux/compiler-intel.h +++ b/include/linux/compiler-intel.h @@ -14,18 +14,31 @@ * It uses intrinsics to do the equivalent things. */ #undef barrier +#undef barrier_data #undef RELOC_HIDE +#undef OPTIMIZER_HIDE_VAR #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() + /* Intel ECC compiler doesn't support __builtin_types_compatible_p() */ #define __must_be_array(a) 0 #endif -#define uninitialized_var(x) x +#ifndef __HAVE_BUILTIN_BSWAP16__ +/* icc has this, but it's called _bswap16 */ +#define __HAVE_BUILTIN_BSWAP16__ +#define __builtin_bswap16 _bswap16 +#endif diff --git a/include/linux/compiler.h b/include/linux/compiler.h index cc8c4de43..8f0c29203 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -10,6 +10,7 @@ # define __force __attribute__((force)) # define __nocast __attribute__((nocast)) # define __iomem __attribute__((noderef, address_space(2))) +# define __must_hold(x) __attribute__((context(x,1,1))) # define __acquires(x) __attribute__((context(x,0,1))) # define __releases(x) __attribute__((context(x,1,0))) # define __acquire(x) __context__(x,1) @@ -27,6 +28,7 @@ extern void __chk_io_ptr(const volatile void __iomem *); # define __chk_user_ptr(x) (void)0 # define __chk_io_ptr(x) (void)0 # define __builtin_warning(x, y...) (1) +# define __must_hold(x) # define __acquires(x) # define __releases(x) # define __acquire(x) (void)0 @@ -34,6 +36,10 @@ extern void __chk_io_ptr(const volatile void __iomem *); # define __cond_lock(x,c) (c) #endif +/* Indirect macros required for expanded argument pasting, eg. __LINE__. */ +#define ___PASTE(a,b) a##b +#define __PASTE(a,b) ___PASTE(a,b) + #ifdef __KERNEL__ #ifdef __GNUC__ @@ -49,6 +55,13 @@ extern void __chk_io_ptr(const volatile void __iomem *); # include #endif +/* Clang compiler defines __GNUC__. So we will overwrite implementations + * coming from above header files here + */ +#ifdef __clang__ +#include +#endif + /* * Generic compiler-dependent macros required for kernel * build go below this comment. Actual compiler/compiler version @@ -144,6 +157,10 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect); # define barrier() __memory_barrier() #endif +#ifndef barrier_data +# define barrier_data(ptr) barrier() +#endif + /* Unreachable code */ #ifndef unreachable # define unreachable() do { } while (1) @@ -156,6 +173,15 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect); (typeof(ptr)) (__ptr + (off)); }) #endif +#ifndef OPTIMIZER_HIDE_VAR +#define OPTIMIZER_HIDE_VAR(var) barrier() +#endif + +/* Not-quite-unique ID. */ +#ifndef __UNIQUE_ID +# define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __LINE__) +#endif + #endif /* __KERNEL__ */ #endif /* __ASSEMBLY__ */ @@ -228,7 +254,7 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect); /* * Rather then using noinline to prevent stack consumption, use - * noinline_for_stack instead. For documentaiton reasons. + * noinline_for_stack instead. For documentation reasons. */ #define noinline_for_stack noinline @@ -270,11 +296,20 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect); # define __section(S) __attribute__ ((__section__(#S))) #endif +#ifndef __visible +#define __visible +#endif + /* Are two types/vars the same type (ignoring qualifiers)? */ #ifndef __same_type # define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) #endif +/* Is this type a native word size -- useful for atomic operations */ +#ifndef __native_word +# define __native_word(t) (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long)) +#endif + /* Compile time object size, -1 for unknown */ #ifndef __compiletime_object_size # define __compiletime_object_size(obj) -1 @@ -284,7 +319,48 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect); #endif #ifndef __compiletime_error # define __compiletime_error(message) +/* + * Sparse complains of variable sized arrays due to the temporary variable in + * __compiletime_assert. Unfortunately we can't just expand it out to make + * sparse see a constant array size without breaking compiletime_assert on old + * versions of GCC (e.g. 4.2.4), so hide the array from sparse altogether. + */ +# ifndef __CHECKER__ +# define __compiletime_error_fallback(condition) \ + do { ((void)sizeof(char[1 - 2 * condition])); } while (0) +# endif #endif +#ifndef __compiletime_error_fallback +# define __compiletime_error_fallback(condition) do { } while (0) +#endif + +#define __compiletime_assert(condition, msg, prefix, suffix) \ + do { \ + bool __cond = !(condition); \ + extern void prefix ## suffix(void) __compiletime_error(msg); \ + if (__cond) \ + prefix ## suffix(); \ + __compiletime_error_fallback(__cond); \ + } while (0) + +#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_, __LINE__) + +#define compiletime_assert_atomic_type(t) \ + compiletime_assert(__native_word(t), \ + "Need native word sized stores/loads for atomicity.") /* * Prevent the compiler from merging or refetching accesses. The compiler @@ -293,11 +369,22 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect); * to make the compiler aware of ordering is to put the two invocations of * ACCESS_ONCE() in different C statements. * - * This macro does absolutely -nothing- to prevent the CPU from reordering, - * merging, or refetching absolutely anything at any time. Its main intended - * use is to mediate communication between process-level code and irq/NMI - * handlers, all running on the same CPU. + * ACCESS_ONCE will only work on scalar types. For union types, ACCESS_ONCE + * on a union member will work as long as the size of the member matches the + * size of the union and the size is smaller than word size. + * + * The major use cases of ACCESS_ONCE used to be (1) Mediating communication + * between process-level code and irq/NMI handlers, all running on the same CPU, + * and (2) Ensuring that the compiler does not fold, spindle, or otherwise + * mutilate accesses that either do not require ordering or that interact + * with an explicit memory barrier or atomic instruction that provides the + * required ordering. + * + * If possible use READ_ONCE()/WRITE_ONCE() instead. */ -#define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x)) +#define __ACCESS_ONCE(x) ({ \ + __maybe_unused typeof(x) __var = (__force typeof(x)) 0; \ + (volatile typeof(x) *)&(x); }) +#define ACCESS_ONCE(x) (*__ACCESS_ONCE(x)) #endif /* __LINUX_COMPILER_H */