EVOLUTION-MANAGER

Edit File: compiler-gcc.h

#ifndef __LINUX_COMPILER_H #error "Please don't include <linux/compiler-gcc.h> directly, include <linux/compiler.h> instead." #endif /* * 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 * shouldn't recognize the original var, and make assumptions about it. * * This is needed because the C standard makes it undefined to do * pointer arithmetic on "objects" outside their boundaries and the * gcc optimizers assume this is the case. In particular they * assume such arithmetic does not wrap. * * A miscompilation has been observed because of this on PPC. * To work around it we hide the relationship of the pointer and the object * using this macro. * * Versions of the ppc64 compiler before 4.1 had a bug where use of * RELOC_HIDE could trash r30. The bug can be worked around by changing * 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)); \ }) /* 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(__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) || \ !defined(CONFIG_OPTIMIZE_INLINING) || (__GNUC__ < 4) #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 __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. * * 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)) noinline __noclone notrace #define __noreturn __attribute__((noreturn)) /* * From the GCC manual: * * Many functions have no effects except the return value and their * return value depends only on the parameters and/or global * variables. Such a function can be subject to common subexpression * elimination and loop optimization just as an arithmetic operator * would be. * [...] */ #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)) /* 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 # define __compiletime_object_size(obj) __builtin_object_size(obj, 0) #define __nostackprotector __attribute__((__optimize__("no-stack-protector"))) #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 >= 40902 /* * Tell the compiler that address safety instrumentation (KASAN) * should not be applied to that function. * Conflicts with inlining: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368 */ #define __no_sanitize_address __attribute__((no_sanitize_address)) #endif #endif /* gcc version >= 40000 specific checks */ #if !defined(__noclone) #define __noclone /* not needed */ #endif #if !defined(__no_sanitize_address) #define __no_sanitize_address #endif /* * A trick to suppress uninitialized variable warning without generating any * code */ #define uninitialized_var(x) x = x