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Diffstat (limited to 'c_src/include/linux/compiler.h')
| -rw-r--r-- | c_src/include/linux/compiler.h | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/c_src/include/linux/compiler.h b/c_src/include/linux/compiler.h new file mode 100644 index 00000000..3ecc3dd1 --- /dev/null +++ b/c_src/include/linux/compiler.h @@ -0,0 +1,190 @@ +#ifndef _TOOLS_LINUX_COMPILER_H_ +#define _TOOLS_LINUX_COMPILER_H_ + +/* Optimization barrier */ +/* The "volatile" is due to gcc bugs */ +#define barrier() __asm__ __volatile__("": : :"memory") +#define barrier_data(ptr) __asm__ __volatile__("": :"r"(ptr) :"memory") + +#ifndef __always_inline +# define __always_inline inline __attribute__((always_inline)) +#endif + +#ifndef __attribute_const__ +#define __attribute_const__ __attribute__((__const__)) +#endif + +#ifdef __ANDROID__ +/* + * FIXME: Big hammer to get rid of tons of: + * "warning: always_inline function might not be inlinable" + * + * At least on android-ndk-r12/platforms/android-24/arch-arm + */ +#undef __always_inline +#define __always_inline inline +#endif + +#define noinline +#define noinline_for_stack noinline + +#define __user +#define __kernel + +#define __pure __attribute__((pure)) +#define __aligned(x) __attribute__((aligned(x))) +#define __printf(a, b) __attribute__((format(printf, a, b))) +#define __used __attribute__((__used__)) +#define __maybe_unused __attribute__((unused)) +#define __always_unused __attribute__((unused)) +#define __packed __attribute__((__packed__)) +#define __flatten __attribute__((flatten)) +#define __force +#define __nocast +#define __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 __cond_acquires(x) +#define __releases(x) +#define __acquire(x) (void)0 +#define __release(x) (void)0 +#define __cond_lock(x,c) (c) +#define __percpu +#define __rcu +#define __sched +#define __init +#define __exit +#define __private +#define __must_check +#define __malloc +#define __weak __attribute__((weak)) +#define likely(x) __builtin_expect(!!(x), 1) +#define unlikely(x) __builtin_expect(!!(x), 0) +#define unreachable() __builtin_unreachable() +#define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) +#define fallthrough __attribute__((__fallthrough__)) +#define __noreturn __attribute__((__noreturn__)) + +#ifndef __counted_by +#define __counted_by(nr) +#endif + +#define ___PASTE(a,b) a##b +#define __PASTE(a,b) ___PASTE(a,b) +#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __LINE__) + +#define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x)) + +#define __initcall(x) /* unimplemented */ +#define __exitcall(x) /* unimplemented */ + +#include <linux/types.h> + +/* + * Following functions are taken from kernel sources and + * break aliasing rules in their original form. + * + * While kernel is compiled with -fno-strict-aliasing, + * perf uses -Wstrict-aliasing=3 which makes build fail + * under gcc 4.4. + * + * Using extra __may_alias__ type to allow aliasing + * in this case. + */ +typedef __u8 __attribute__((__may_alias__)) __u8_alias_t; +typedef __u16 __attribute__((__may_alias__)) __u16_alias_t; +typedef __u32 __attribute__((__may_alias__)) __u32_alias_t; +typedef __u64 __attribute__((__may_alias__)) __u64_alias_t; + +static __always_inline void __read_once_size(const volatile void *p, void *res, int size) +{ + switch (size) { + case 1: *(__u8_alias_t *) res = *(volatile __u8_alias_t *) p; break; + case 2: *(__u16_alias_t *) res = *(volatile __u16_alias_t *) p; break; + case 4: *(__u32_alias_t *) res = *(volatile __u32_alias_t *) p; break; + case 8: *(__u64_alias_t *) res = *(volatile __u64_alias_t *) p; break; + default: + barrier(); + __builtin_memcpy((void *)res, (const void *)p, size); + barrier(); + } +} + +static __always_inline void __write_once_size(volatile void *p, void *res, int size) +{ + switch (size) { + case 1: *(volatile __u8_alias_t *) p = *(__u8_alias_t *) res; break; + case 2: *(volatile __u16_alias_t *) p = *(__u16_alias_t *) res; break; + case 4: *(volatile __u32_alias_t *) p = *(__u32_alias_t *) res; break; + case 8: *(volatile __u64_alias_t *) p = *(__u64_alias_t *) res; break; + default: + barrier(); + __builtin_memcpy((void *)p, (const void *)res, size); + barrier(); + } +} + +/* + * Prevent the compiler from merging or refetching reads or writes. The + * compiler is also forbidden from reordering successive instances of + * READ_ONCE, WRITE_ONCE and ACCESS_ONCE (see below), but only when the + * compiler is aware of some particular ordering. One way to make the + * compiler aware of ordering is to put the two invocations of READ_ONCE, + * WRITE_ONCE or ACCESS_ONCE() in different C statements. + * + * In contrast to ACCESS_ONCE these two macros will also work on aggregate + * data types like structs or unions. If the size of the accessed data + * type exceeds the word size of the machine (e.g., 32 bits or 64 bits) + * READ_ONCE() and WRITE_ONCE() will fall back to memcpy and print a + * compile-time warning. + * + * Their two major use cases are: (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. + */ + +#define READ_ONCE(x) \ + ({ union { typeof(x) __val; char __c[1]; } __u; __read_once_size(&(x), __u.__c, sizeof(x)); __u.__val; }) + +#define WRITE_ONCE(x, val) \ + ({ union { typeof(x) __val; char __c[1]; } __u = { .__val = (val) }; __write_once_size(&(x), __u.__c, sizeof(x)); __u.__val; }) + +#define lockless_dereference(p) \ +({ \ + typeof(p) _________p1 = READ_ONCE(p); \ + typeof(*(p)) *___typecheck_p __maybe_unused; \ + smp_read_barrier_depends(); /* Dependency order vs. p above. */ \ + (_________p1); \ +}) + +#define flush_cache_all() do { } while (0) +#define flush_cache_mm(mm) do { } while (0) +#define flush_cache_dup_mm(mm) do { } while (0) +#define flush_cache_range(vma, start, end) do { } while (0) +#define flush_cache_page(vma, vmaddr, pfn) do { } while (0) +#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0 +#define flush_dcache_page(page) do { } while (0) +#define flush_dcache_mmap_lock(mapping) do { } while (0) +#define flush_dcache_mmap_unlock(mapping) do { } while (0) +#define flush_icache_range(start, end) do { } while (0) +#define flush_icache_page(vma,pg) do { } while (0) +#define flush_icache_user_range(vma,pg,adr,len) do { } while (0) +#define flush_cache_vmap(start, end) do { } while (0) +#define flush_cache_vunmap(start, end) do { } while (0) + +#ifdef __x86_64 +#define CONFIG_X86_64 y +#endif + +#define __is_constexpr(x) \ + (sizeof(int) == sizeof(*(8 ? ((void *)((long)(x) * 0l)) : (int *)8))) +#define is_signed_type(type) (((type)(-1)) < (__force type)1) +#define is_unsigned_type(type) (!is_signed_type(type)) + +#endif /* _TOOLS_LINUX_COMPILER_H */ |